It 
 
 \ 
 
 THE LIBRARY 
 
 OF 
 
 THE UNIVERSITY 
 
 OF CALIFORNIA 
 
 RIVERSIDE 
 
 Ex Libris 
 C. K. OGDEN
 
 THE WORKS 
 
 OF 
 
 THOMAS EEID, D.D. 
 
 NOW FULLY COLLECTED, 
 WITH SELECTIONS FROM HIS UNPUBLISHED LETTEES. 
 
 PREFACE, 
 NOTES AND SUPPLEMENTARY DISSERTATIONS, 
 
 BY 
 
 SIR WILLIAM HAMILTON, BART., 
 
 advocate; a.m. (oxon.); etc.; corresponding member of the institute of fkance; 
 
 honorary member of the american academy of arts and sciences ; of the 
 
 latin society of jena; etc.; professor of logic and metaphysics 
 
 in the csiversity of edinbcrgh. 
 
 PREFIXED,' 
 STEWART'S ACCOUNT OF THE LIFE AND "WRITINGS OF REID. 
 
 VOL. I. 
 
 SEVENTH EDITION. 
 
 EDINBUEGH: 
 
 MACLACHLAN AND STEWART. 
 LONDON : LONGMAN, GREEN, LONGMAN, ROBERTS, AND GREEN. 
 
 MDCCCLXXII.
 
 1^, /5-^2. 
 
 V.I 
 
 ON EARTH, THERE IS NOTHING GREAT BUT MAN; 
 IN MAN, THERE IS NOTHING GREAT BUT MIND.
 
 TO 
 
 VICTOR COUSIN, 
 
 PEER OF FRANCE, LATE MINISTER OF PUBLIC INSTRUCTION, 
 MEMBER OF THE INSTITUTE, PROFESSOR OF PHILOSOPHY, 
 
 ETC., ETC., 
 
 THIS EDITION OF THE WORKS OF REID 
 
 IS DEDICATED J 
 
 NOT ONLY, 
 
 IN TOKEN OF THE EDITOR'S ADMIRATION 
 
 OF 
 THE FIRST PHILOSOPHER OF FRANCE, 
 BUT, 
 AS A TRIBUTE, DUE APPROPRIATELY AND PRE-EMINENTLY 
 
 TO 
 
 THE STATESMAN, 
 
 THROUGH WHOM 
 
 SCOTLAND HAS BEEN AGAIN UNITED INTELLECTUALLY 
 
 TO HER OLD POLITICAL ALLY, 
 
 AND 
 
 THE AUTHOR'S WRITINGS, 
 
 (THE BEST RESULT OF SCOTTISH SPECULATION,) 
 
 MADE THE BASIS OF ACADEMICAL INSTRUCTION IN PHILOSOPHY 
 
 THROUGHOUT THE CENTRAL NATION OF EUROPE.
 
 ADVERTISEMENT. 
 
 November 1846. — The present issue (ending with page 914) con- 
 tains the whole Works of Reid, hitherto pubhshed, with many of his 
 writings, printed or collected for the first time. The text has been 
 collated, revised, and corrected ; useful distinctions and supplements 
 inserted ; the leading words and propositions marked out ; the allu- 
 sions indicated ; the quotations filled up. It contains also the Foot- 
 Notes of the Editor on the texts of Reid and Stewart, and a large 
 proportion (in length) of the Editor's Supplementary Dissertations. 
 There remain the sequel of these Dissertations, the General Pre- 
 face, and the Indices ; — all of which are cither prepared, or their 
 materials collected. These (Deo volcntc) will be comprised in a con- 
 cluding issue, and title-pages for two volumes then given. The 
 Notes and Dissertations have insensibly increased to a size and 
 importance far beyond what was ever anticipated ; but the book 
 having been always destined primarily for academical use, the price 
 of the whole will not exceed thirty shiUings. Being stereotyped, 
 what additions may be made to any subsequent edition, will be pub- 
 lished also apart. 
 
 It is proper to state : — that the Foot-notes were written, as the 
 texts passed through the press, in 1837 and 1838 ; that the Supple- 
 mentary Dissertations, to the end of D*, were written and stereotyped 
 in 1841 and 1842 ; the rest being added recently. 
 
 [^October 18G3 — In the present edition the errata have been, for 
 the most part, corrected on the stereotype plates; the Indices have 
 been added ; and the sequel of the Dissertations has been, so far as 
 possible, completed from Sir W. Hamilton's MSS. For an account 
 of what has been done in tbis last respect, tlie reader is referred to 
 the Postscript at the end of the Supplementary Dissertations.]
 
 CONTENTS. 
 
 Page 
 Dedication, ...... 
 
 Table of Contents, ..... iii 
 
 EDITOR'S PREFACE, .... xv 
 
 DUGALD STEWART'S ACCOUNT OF THE LIFE AND WRITINGS 
 OF THOMAS REID, D.D. 
 
 Section I. From Br Eeid's birth till the date of his latest publication, 3 
 
 II. Observations on the Spirit and scope of Dr Reid's philosophy, 11 
 
 HI. Conclusion of the Narrative, ... 29 
 
 Notes, .... 35 
 
 RE ID'S 
 
 (I.— WRITINGS NOT INTENDED FOR PUBLICATION.) 
 
 LETTERS. 
 
 A. — To Drs Andrew and David Skene, 1764 — 1770, . . 39 
 
 B.— To Lord Kumes,\1T2—\182, . . .60 
 
 C— To Dr James Gregory, IIQZ—nQZ, ... 62 
 
 D. — To the Rev. Archibald Alison, 1790, ... 89 
 
 E. — To Prof. Robison, 1792, . . . . ,89 
 
 F. — To David Hume, 1763, . • . . 91 
 
 (11.— WRITINGS INTENDED AND PREPARED FOR PUBLICATION.) 
 
 A— INQUIRY INTO THE HUMAN MIND. 
 
 Dedication, ..... 95 
 
 CHAPTER I.— Intkoduction. 
 
 Section I. The Importance of the subject, and the Means of prosecuting it, 97 
 
 II. The Impediments to our knowledge of the mind, . 98 
 
 III. Tlie Present Stale of this part of philotopihy. Of Des Cartes, Male- 
 
 branche, and Locke, .... 99 
 
 IV. Apjology for thoae pjhilosoijhers, . . 101 
 V. Of Bishop Berkeley ; the " Treatise of Human Nature " \by Hume . ] 
 
 and of Scepticism, .... 101 
 
 Ml. Of the '' Treatise of Human Nature," . . 102 
 
 The system of all these authors is the same, and leads to Scepticism, 103 
 
 We ought not to desjtair of a better, . . . 103 
 
 VII. 
 VIII. 
 
 CHAPTER II.— Of Smelling. 
 
 Section I. The Order of proceeding. Of the medium and organ of Smell, 10-1 
 
 II. The Sensation considered abstractly, . . 105 
 
 III. Sensation and Remembrance, natural principles of Belief , 105 
 
 IV. Judgment and Belief in some cases precede Simple Apprehension, 106 
 V. Two Theories of the nature of Belief refuted. Conclusions from 
 
 what hath been said, . . . 107
 
 iv CONTENTS. 
 
 Pagh 
 Section VI. Ajwlogy for metaphysical ahsurdities. Sensation loilhoul a sentient, 
 a consequence of the theory of Ideas. Conseqtiences of this strange 
 opinion, ..... 106 
 
 VII. The conception and belief of a sentient being or Mind, is suggested 
 by our constitution. The notion of Relations not always got by 
 Comparing the related ideas, . . . 110 
 
 VIII. There is a quality or virtue in bodies, which we call their Smell. 
 
 How this is connected in the imagination with the sensation, 112 
 
 IX. That there is a principle in human nature, from which the notion 
 
 of this, as well as all other natural virtues or causes, is derived, 112 
 X. Whether in Sensation the mind is Active or Passive, . 114 
 
 CHAPTER III.— Of Tasting, . . 115 
 
 CHAPTER IV Of Hearing. 
 
 Section I. Variey of Sounds. Their place and distance learned by Custom, 
 
 u'ithout reasoning, • . . , 116 
 
 tl. Of Natural Language, . . . . 117 
 
 CHAPTER v.— Of Touch. 
 
 Sbction I. Of Heat and Cold, . . . • 119 
 
 II. Of Hardness and Softness, . . . 119 
 
 III. Of Natural Signs, . . . .121 
 
 IV. Of Hardness and other Primary Qualities, ■ . 123 
 V. Of Extension, . . . . .123 
 
 VI. Of Extension, .... 125 
 
 VII. Of the existence of a Material World, . . 126 
 
 VIII. Of the Systems of Philosophers concerning the Senses, . 130 
 
 CHAPTER VI.— Of Seeing. 
 
 Section I. The excellence and dignity of this faculty, . . 132 
 II. Sight discovers almost nothing which the Blind may not compre- 
 hend. The reason of this, . . . 133 
 
 III. Of the Visible Appearances of objects, . . 135 
 
 IV. That Colour is a quality of bodies, not a sensation of the mind, 137 
 V. An inference from the jjreceding, ■ . . 138 
 
 VI. That none of our sensations are Resemblances of any cf the quali- 
 ties of bodies, 
 
 VII. Of visible Figure and Extension, 
 
 VIII. Some Queries concerning Visible Figure answered, 
 
 IX. Of the Geometry of Visibles, 
 
 X. Of the Parallel Motion of the eyes, 
 
 XI. Of our seeing objects Erect by inverted images, 
 
 XII. The same subject continued, 
 
 XIII. Of seeing objects Single with two eys, 
 
 XIV. Of the laws of vision in Brute animals, 
 XV. Squinting considered hypothetically, 
 
 XVI. Facts relating to Squinting, 
 XVII. Of the effect of Custom in seeing objects Single, . . 173 
 
 XVIII. Of Dr Porterfe'd's account of single and double vision, 176 
 
 XIX. Of Dr Briggs's theory, and Sir Isaac Newton'' s conjecture on this 
 
 subject, . . . . . 178 
 
 XX. 0/ Perception in general, . . . 182 
 
 140 
 142 
 144 
 147 
 152 
 163 
 156 
 163 
 166 
 167 
 172
 
 CONTENTS. V 
 
 Tags 
 
 Section- XXI. Of the Process of Nature in percej^tion, . . 186 
 
 XXII. Of the Signs by ivhich we learn to perceive Distance from the eye, 188 
 
 XXIII. Of the Signs iised in other acquired j)erceptions, . 193 
 
 XXIV. Of the Analogy betiveen P rccption, and the credit vie give to 
 
 Human Testimony, . . . 194 
 
 CHAPTER VII.— Conclusion. 
 Containing Reflections upon the opiniotis of Philosophers on this subject, 
 
 201 
 
 B.— ESSAYS ON THE INTELLECTUAL POWERS OF MAN. 
 
 Dedication, 
 Preface, 
 
 Chapter I. 
 
 II. 
 
 III. 
 
 IV. 
 
 V. 
 
 VI. 
 
 VII. 
 
 VIII. 
 
 ESSAY I. — Preliminary. 
 
 Explication of Words, .... 
 
 Principles taken for granted, 
 
 Of Hypotheses, .... 
 
 Of Analogy, .... 
 
 Of the proper means of Knowing the operations of the mind, 
 
 Of the dijficidty of Attending to the operations of our oivn minds, 
 
 Bioision of the pioivers of the mind, 
 
 Of Social [and Solitary] operations of mind. 
 
 215 
 216 
 
 219 
 
 230 
 234 
 236 
 238 
 240 
 242 
 244 
 
 ESSAY II. — Of the Powers wf. have by means of our External Slnses. 
 
 Chapter 
 
 I. 
 
 II. 
 
 III. 
 
 IV. 
 
 V. 
 
 VI. 
 
 VII. 
 
 VIII. 
 
 IX. 
 X. 
 
 XI. 
 
 XII. 
 XIII. 
 XIV. 
 
 XV. 
 
 XVI. 
 
 XVII. 
 
 XVIIl. 
 
 XIX. 
 
 XX. 
 
 XXI, 
 
 XXII 
 
 Of the Organs of Sense, .... 245 
 
 Of the Impressions on the organs, nerves, and brain, 247 
 
 Hypothesis concerning the Nervis and Brain, . 248 
 
 False Conclusions drawn from the impressions before mentioned, 253 
 
 Of Perception, . . ' . . 258 
 
 What it is to Account for a Phenomenon in Nature, 200 
 Sentiments of Philosophers about the Perceptions of External 
 
 objects ; and firsts of the theory of Father Malelranche, 202 
 Of the Common, Theory of Perception ; and of the sentiments of 
 
 the Peripatetics, and of Des Cartes, . . 2G7 
 The sentiments of Mr Locke, . . . 275 
 The sentiments of Bishop Berkeley, . . . 280 
 Bishop Berkeley's sentiments of the nature of Ideas, 287 
 The sentiments of Mr Hume, . . • 292 
 The sentiments of Anthony Arnauld, . . 295 
 Reflections on the Common Theory of Ideas, . . 298 
 Account of the system of Leibnitz, . . 306 
 Of Sensation, .... 310 
 Of the Objects of Perception; and first, of Primary and Second- 
 ary Qualities, . . . . 313 
 Of other objects of Perception, . . . 319 
 Of Matter and of Space, . . . 322 
 Of the Evidence of Sense, and of Belief in general, . 326 
 Of thi Improvem nt of the Senses, . . . 330 
 Of t/ie Fallacy of the Senses, , . . 334
 
 vi CONTENTS. 
 
 pAoa 
 ESSAY III.— Of Memort. 
 
 CuAFTER I. Things obvious and certain with regard to Memory, , 339 
 
 II. Memory an original faculty, . . . 340 
 
 III. Of Duration, ..... 342 
 
 IV. Of Identity, ..... 344 
 V. Mr Locke's account of the Origin of our Ideas, and particularly 
 
 of the idea of Duration, . . . 346 
 
 VI. Mr Locke's account of our Personal Identity, . 350 
 
 VII. Theories concerning Memory, . . . 353 
 
 ESSAY IV._Of Conception. 
 
 Chapter I. Of Conception, or Simple Apprehension in general, . 360 
 
 II, Theories concerning Conception, . . 368 
 
 III. Mistakes concerning Conception, . . . 375 
 
 IV. Of the Train of Thought in the mind, . . 379 
 
 ESSAY v.— Of Abstraction. 
 
 Chapter I. Of General Words, .... 389 
 
 II. Of General Conceptions, . . . 391 
 
 III. Of general conceptions formed by Analysing objects, . 394 
 
 IV. Of general conceptions formed by Combination, . 398 
 V. Observations concerning the Names given to our general notions, 403 
 
 VI. Opinion of philosophers about Universals, . . 405 
 
 ESSAY VI.— Of Judgment. 
 
 Chapter I. Of Judgment in general, . - . . 413 
 
 II. Of Common Sense, .... 421 
 
 III. Sentiments of philosophers concerning Judgment, . 426 
 
 IV. Of First Princijyles in general, • • . 434 
 V. The first princip>les of Contingent Truths. \^0n Consciousness,'\ 441 
 
 VI. First principles of Necessary Truths, . . 452 
 
 VII. Opinions, ancient and modern, about First Principles, , 462 
 
 VIII. Of Prejudices, the causes of trror, . . 468 
 
 ESSAY VII.— Of Reasoning. 
 
 Chapter I. Of Eeas07iing in general, and of Demonstration, . 475 
 
 II. Whether 3Iorality be capable of demonstration, . 478 
 
 III. Of Probable Reasoning, . . . .481 
 
 IV. Of 3fr Hume's Scepticism with regard to Reason, , 484 
 
 ESSAY VIII.— Of Taste. 
 
 Chapter I. Of Taste in general, . . . , 490 
 
 II. Of the Objects of taste, and frst of Novelty, . 493 
 
 JII. Of Grandeur, .... 494 
 
 rV. Of Beauty, ..... 498
 
 CONTENTS. >' U 
 
 C— ESSAYS ON THE ACTIVE POWERS OF THE HUMAN 
 
 MIND. 
 
 Introduction, ...... 51] 
 
 ESSAY I. — Of Active Power in General. 
 
 CoiPTER I. Of the Notion of Active Power, . . . 512 
 
 II. 77*6 sa7ne subject, . . . .515 
 
 III. Of Mr Locke's account of our Idea of Poiuer, . 518 
 
 IV. Of Mr Hume's 02nnion of the Idea of Power, . . 52O 
 V. Whether beings that have no Will nor Understanding may have 
 
 Active Power ? . . . . 622 
 
 VI. Of the Effici-nt Causes of the phcenomena of nature, . 525 
 
 VII. Of the Extent of Human Porver, . . . 527 
 
 ESSAY II.— Of the Will. 
 
 Chapter I. Observations concerning the Will, . . . 530 
 
 II. Of the influence of Incitements and Motives vpon the Will, 533 
 
 III. Of operations of mind which may be called Voluntary, 537 
 
 tV. Corollaries, . . . 541 
 
 ESSAY III. — Of the Piunciples of Action. 
 PART I. — Op the Mechamcal Principles of Action. 
 
 Chapter I. Of the Principles of Action in general, 
 II. Of Instinct, 
 III. Of Habit, 
 
 PART II Op the Anijul Principles op Action 
 
 Chapter I. Of Appetites, 
 II. Of Desires, 
 
 III. Of Benevolent Affection in general 
 
 IV. Of the particular Benevolent Affections, 
 V. Of Malevolent Affections, 
 
 VI. Of Passion, 
 VII. Of Disposition, 
 VIII. Of Opinion, 
 
 PART III. — Op the Rational Principles op Action. 
 
 543 
 545 
 550 
 
 651 
 554 
 
 658 
 660 
 666 
 670 
 675 
 677 
 
 Chapter I. There are Rational Principles of action in man, . 670 
 
 II. Of regard to our Good upon the Whole, . 680 
 
 III. The Tendency of this Principle, . . 582 
 
 IV. Defects of this Principle, .... 584 
 V. Of the notion of Duty, Rectitude, Moral Obligation, . 688 
 
 VI. Of the Sense of Duty, . . . . 589 
 
 VII. Of Moral Approbation and Disapprobation, . , 592 
 
 VIII. Observations concerning Conscience, . . • 594 
 
 ESSAY IV. — Of the Liberty of Moral Agents. 
 
 CnArTEu I. The notions of Moral Liberty and Necessity stated, . 699 
 
 II. Of the words, Cause and Effect, Action, and Active Power, V>0'A
 
 vn( 
 
 CONTENTS. 
 
 Chai-teu hi. Causes of the Ambiguity of those toordf 
 IV. Of the infimnce of Motives, 
 V. Liberty consistent with Government, 
 VI. First Argument for Liberlij, 
 VII. Second Argument, 
 VIII. Third Argument^ 
 IX. Of Arguments for Necessity, 
 X. The same subject, 
 XL Of the Pur mission of Evil, 
 
 Page 
 
 605 
 608 
 613 
 616 
 620 
 622 
 624 
 629 
 632 
 
 ESSAY v.— Of Morals. 
 
 Cbapteu I. Of the First Principles of Morals, . . . 637 
 
 II. Of Systems of Morals, . . . 640 
 
 III. Of Systi^ms of Natural Jurisprudence, . . 643 
 
 IV. Whether an action deserving Moral Approbation, must be done 
 
 with the Belief of its being Morally Good, . 646 
 
 V. Whether Justice be a Natural or an Artificial Virtue, . 651 
 
 VI. Of the nature and obligation of a Contract, . 662 
 
 VII. That Moral Approbation implies a real Judgment, . 670 
 
 D— ACCOUNT OF ARISTOTLE'S LOGIC. 
 CHAPTER I.— Of the First Thbee Treatises. 
 
 Section I. Of the Author, .... 
 
 II. Of the Porphyry's Introduction, 
 
 III. Of the Categories, 
 
 IV. Of the book Concerning Interpretation, 
 
 681 
 
 683 
 683 
 
 685 
 
 CHAPTER II.~Remarks. 
 
 SiiCTioN I. On the Five Predicables, . . . 
 
 II. On tlie Ten Categories, and on Divisions in general, 
 
 I I I. On Distinctions, .... 
 
 IV. On Definitions, 
 
 V. On the structure of Speech, 
 VI. On Propositions, 
 
 685 
 687 
 689 
 i690 
 691 
 692 
 
 CHAPTER III. — Account of the First Analytics. 
 
 Section I. Of the Conversion of Propositions, 
 
 II. Of the Figures iind Modes of Pure Syllogisms, 
 
 III. Of the Invention \_Discovery\ of a Middle Term, 
 
 IV. Of the remaining part of the First Book, . . 
 V. Of the Second Book of the First Analytics, 
 
 693 
 694 
 695 
 695 
 69E 
 
 CHAPTER IV.— Remarks. 
 8ECTIo^ T. Of the Conversion of Propositions, „ 
 
 696
 
 CONTENTS. IX 
 
 Pa (IE 
 
 Section II. On Additions made to Aristotle's Theory, . . 697 
 
 III. On Examples used to illustrate this Theory, . , G98 
 
 IV. On the Demonstration of the Theory, . . 699 
 V. On this Theory considered as an Engine of Science, . 701 
 
 VI. On Modal Syllogisms, .... 702 
 
 VII. On Syllogisms that do not belong to Figure and Mode, . 704 
 
 CHAPTER V. — Account of the Remaining Books of the Organon. 
 
 Section I. Of the Last Analytics, .... 705 
 
 II. Of the Topics, .... 706 
 
 III. Of the hook concerning Sojjhisms, . . . JQj 
 
 CHAPTER VI.— Reflections on the Utility of Logic, and the Means of 
 
 ITS Imphovement. 
 
 Section I. Of the Utility of Logic, .... 703 
 
 II. Of the Improvement of Logic, . . . 711 
 
 E — ESSAY ON QUANTITY. 
 
 [Occasion and grounds of the Discussion,!^ .... 715 
 
 Of the Newtonian Measure of Force, . . . . 717 
 
 Of the Leibnitzian Measure of Force, . . . . 718 
 
 Reflections on this Controversy, . . . . 719 
 
 F.-,ACCOUNT OF THE UNIVERSITY OF GLASGOW. 
 
 Introduction, ...... 721 
 
 I. History of the University before the Reformation, . . 721 
 
 II. Ayicient Constitution, .... 722 
 
 III. History after the Reformation, . . . 727 
 
 IV. Modern Constitution, > . . . . 7-9 
 V. Donations, ... . . 730 
 
 VI. Presmt State, . . . . . 732 
 
 VII. Conclusion, .... 738 
 
 EDITOR'S SUPPLEMENTARY DISSERTATIONS. 
 
 (A.)— ON THE PHILOSOPHY OF COMMON SENSE; OR, OUR PRIMARY 
 BELIEFS CONSIDERED AS THE ULTIMATE CRITERION OF TRUTH. 
 
 Section I. The Meaning of the Doctrine, and Purport of the Argument, of 
 
 Common Sense, .... 742 
 
 II. The Conditions of the Legitimacy, and legitimate application, of 
 
 the argument, . . . 749 
 
 HI. That it is one strictly Philosophical and scientific, . 7.51 
 
 IV. The Essential Cliaracters by which onr primary biiiefs, or the 
 
 principles of Common Sense, are discriminated, . 7.'J4 
 
 V. Tlie Nomenclature, that is, the various appellations by which these 
 
 have been designated, .... 755
 
 X CONTENTS. 
 
 Pao» 
 Section VI. The Universality of the philosophy of Common Sense ; or its general 
 recognition, in reality and in name, shown by a chronological 
 series of Testimonies from the dawn of speculation to the pre- 
 sent day, . . . . 770 
 
 (H.)— OF PRESENTATIVE AND REPRESENTATIVE KNOWLEDGE. 
 
 Sbction I. The distinction of Presentative, Intuitive or Immediate, and of 
 Representative or Mediate cognition ; with the various signifi- 
 cations of the term Object, its conjugates and correlatives, 804 
 
 Section II. Errors of Reid and other Philosophers, in reference to the preced- 
 ing distinctions, . . . . 812 
 
 (C.)— ON THE VARIOUS THEORIES OF EXTERNAL PERCEPTION. 
 
 Section I. Systematic Schemes, from different points of view, of the various 
 theories of the relation of External Perception to its Object ; 
 and of the various systems 6f Philosophy founded thereon, 816 
 
 II. WJiat is the character, in this respect, of Reid's doctrine of Percep- 
 tion? ..... 819 
 
 (D.)— DISTINCTION OF THE PRIMARY AND SECONDARY QUALITIES 
 
 OF BODY. 
 
 Section I. Historically considered, .... 825 
 
 II. Critically considered. Three classes (Primary, Secun do -Primary, 
 
 and Secondary Qualities,) established, . . 815 
 
 (D *.)— PERCEPTION PROPER AND SENSATION PROPER. 
 
 Section I. Principal momenta of the Editor's doctrine of Perception, (A) in 
 itself, and (B) in contrast to that of Reid, Steivart, Royer 
 Collard, and other philosophers of the Scottish School, 876 
 
 II. Historical notices in regard to the distinction of PercepAion proper 
 
 and Sensation proper, .... 886 
 
 (D **.) CONTRIBUTION TOWARDS A HISTORY OF THE DOCTRINE 
 
 OF MENTAL SUGGESTION OR ASSOCIATION, 889 
 
 (D ***.)— OUTLINE OF A THEORY OF MENTAL REPRODUCTION, 
 SUGGESTION OR ASSOCIATION. 
 
 Section I. Laws of Mental Succession, as General. — (A.) Not of Reproduc- 
 tion proper, uniform — (B.) Of Repjroduction proper, not 
 uniform : as possible ; as actual ; as direct, — Abstract or 
 Primary law of Repetition ; as indirect, — Abstract or Primary 
 law of Redintegration, Concrete or Secondary law of Pre- 
 ference, . . . . .910 
 II. Laws of Mental Succession, as Special. — Of Reproduction : — (A.J 
 Abstract or Primary, — modes of the laws of Repetition and 
 Redintegration, one or both ; — (B.) Concrete or Secondary, — 
 modes of the law of Preference. , •
 
 .CONTENTS. XI 
 
 Pagb 
 (E.)— ON THE CORRELATIVE APPREHENSIONS OF COLOUR, 
 AND OF EXTENSION AND FIGURE. 
 
 Section I. On the Correlation of Colour with Extension and Figure in visual 
 
 Perception and Imagination, . . . 917 
 
 II. On the Philosophy of the Point, the Line, and the Surface : in illus- 
 tration of the reality, nature, and visual perception of breadth- 
 less lines, ..... 921 
 
 (F.)— ON LOCKE'S NOTION OF THE CREATION OF MATTER, 924 
 
 (G.)— ON THE HISTORY OF THE WORD IDEA, . 925 
 
 (H.)— ON CONSCIOUSNESS. 
 
 Sectiox I. Reid's reduction of Consciousness to a special faculty sheivn to be 
 inaccurate. Consciousness the fundamental condition of all our 
 "mental energies and affections, . . . 929 
 
 II. Conditions and Lirnitcdions of Consciousness. General Laws of 
 Variety and Succession. Special characteristics of Conscious- 
 ness. Philosophy of the Conditioned in relation to the notions 
 of Substance and Cause, . . . .932 
 
 [III.] Historical references — i. On the conditions of Consciousness ; ii. On 
 
 acts of mind beyond the sphere of Consciousness, . 938 
 
 \J.) ON THE HISTORY OF THE TERMS CONSCIOUSNESS, ATTENTION, 
 
 AND REFLECTION. 
 
 Section I. Extracts explanatory of Sir W. Hamilton s vicio of the distinction 
 between Consciousness, Attention, and Reflection, with special 
 reference to the opinions of Reid and Stewart, . . 940 
 
 II. Historical notices of the XLse of the terms Consciousness, Attention, 
 
 and Reflection, . . . . 942 
 
 (K.)— THAT THE TERMS IMAGE, IMPRESSION, TYPE, &c., IN PHILO- 
 SOPHICAL THEORIES OF PERCEPTION, ARE NOT TO BE 
 TAKEN LITERALLY, . . . , .948 
 
 (L.)— ON THE PLATONIC DOCTRINE OF PERCEPTION, . 950 
 
 (.^L)— ON THE DOCTRINE OF SPECIES, AS HELD BY ARISTOTLE 
 AND THE ARISTOTELIANS. 
 
 [Section I.] Origin of the theory as a metaphysical and physical hypothesis — 
 opinion of Aristotle — of the Schoolmen — theory of intentional 
 species, impressed and expressed, sensible and intelligible — 
 various opini(/ns on the whole hypothesis, . . 951
 
 xii CONTENTS. • 
 
 Paor 
 [Section II.] Translations of passages exhibiting the nominalist doctrine of 
 
 species, , . . • ■ 957 
 
 (N.)— THE CARTESIAN THEORY OF PERCEPTION AND IDEAS, . 961 
 
 (0.)— LOCKE'S OPINION ABOUT IDEAS, ... 966 
 
 (P.)— ON MALEBRANCHE'S THEORY, . . . .966 
 
 (Q)-ON HUME'S ASSERTION ABOUT THE IDEAS OF PO'VVER AND 
 
 CAUSE, AND BROWN'S CRITICISM OF REID, . 968 
 
 (R.)— ON THE CARTESIAN DOUBT, . . . .969 
 
 (S.)— ON REID'S BORROWING FROM GASSENDI THE OPINION OF 
 
 ALEXANDER AND THE NOMINALISTS, . • 970 
 
 (T.)-ON' THE QUALITY OF NECESSITY AS A CRITERION OF THE 
 
 ORIGINALITY OF A COGNITION, . . . '.'71 
 
 (U.)— ON THE ARGUMENT FROM PRESCIENCE AGAINST LIBERTY. 
 
 [Section I.] Liberty vindicated by tlie Philosophy of the Conditimied, . 973 
 
 [1 1.] Impossibility of reconciling Liberty and Prescieyice — various 
 
 theories on this ptoint, . . . .976 
 
 [lU.] Extracts from AquinMS and Cajeta.nus, . . 979 
 
 (U*.)— ON SCIENTIA MEDIA, . . . . .981 
 
 (V.)— ARISTOTLE'S MERITS AS A LOGICIAN : HIS OWN AND KANT'S 
 
 TESTIMONY, ..... 982 
 
 (W.)— THE SCIENCES OF OBSERVATION TO BE STUDIED BEFORE 
 
 THOSE OF REFLECTION, . . . .985
 
 CONTENTS. Xlll 
 
 Page 
 {X.)-OISr THE DIFFEREN^CE BETWEEN CONCEPTIONS (BEGRIFFE) 
 
 AND INTUITIONS (ANSCHAUUNGEN), . . 986 
 
 (Y.)— ON EGOISM, 988 
 
 ADDENDA, ........ 989" 
 
 POSTSCEIPT, 989 
 
 INDICES, . . 991
 
 MEMORANDA FOR PREFACE. 
 
 [From the Advertisemect prefixed to this work, it appears tlicat Sir William 
 Hamilton's coutributious as Editor were intended to include, in addition to the 
 Foot-Notes and Supplementary Dissertations, a General Prefiiee to the whole. This 
 Preface was never written, and its plan can only be conjectured from a few memo- 
 randa mai-ked as intended for it, and some fragments apparently designed to be 
 incorporated with it. The principal of these have been printed below. — Ed. ] 
 
 [0/ the Scottish Philosophy in General] 
 
 Results of Locke's philosophy — Col- 
 lins, &c., see Cousin in Yacherot, [Cours 
 de 1819-20, partie 2, Legon 1.*] Berkeley, 
 Hume — adopted at first by Scottish 
 Bchool; Reid's reaction. 
 
 Hume's scepticism proceeds in two 
 momenta. 
 
 1°, In shewing that the notions of 
 Cause and Efi"ect, Substance and Accident, 
 which he wishes to make merely subjec- 
 tive, have no genuine necessity; (under 
 and after this, but not developed, that 
 even if the necessity be not a bastard 
 one — from custom — it is at best only a 
 legitimate subjective one, and without 
 objective validity.) 
 
 2°, In shewing that the mind is not con- 
 Bcious of any real existence in perception ; 
 that its representations are no guarantee 
 for anything represented {Idealism.) 
 
 Now Kant and Reid both combated 
 Hume. Kant applied himself to the 
 causal nexus ; Reid to the idealism. 
 
 Shew how both were equally intent on 
 shewing that causalitj' is a real neces- 
 sity of mind. Though both only subjective, 
 Kant more articulate. 
 
 How, in regard to idealism, Kant con- 
 firmed Hume, giving his premises, whereas 
 Reid's doctrine, though confused and 
 vacillating, was a real refutation. 
 
 [These memoranda have been partly 
 worked out in a paper printed in the 
 Appendix to the Lectures on Metaphysics, 
 vol. i., p. 392 sq. Another aspect of the 
 Scottish Philosophy, in relation to that of 
 Germany, is indicated in the following 
 fragment, which is apparently related to 
 the reference above, p. 7913. — Ed.] 
 
 * See also M. Cousin's o^vn edition of tlie.so 
 Lectures, Lc^on 2. — Ed. 
 
 It was Jacobi who first in Germany at- 
 tacked the mediate and demonstrating 
 philoso2>hy of the Leibnitians, and sbewed 
 the necessity of immediate knowledge. 
 This he took from Reid. — See Francke, 
 p. 227 sq. Schulze, another great pro- 
 moter of this.— Ibid,, p. 230. 
 
 [The purport of this memorandum is 
 explained by the following extracts, 
 translated from Francke's work. Das 
 selbststaendige und reine Leben des 
 Gefuehls, als des Geistes urspruenglicheu 
 Urtheils, u.s.w. Leiinzig, 1838 : — 
 
 " Tlie union of the English and French 
 empiricism with the German logical ra- 
 tionalism prodviced that maxim of the 
 philosophy of reflection, which maintains 
 that nothing can be admitted as truth 
 which cannot be j^roved, or logically de- 
 duced, from the perception-s of sense ; a 
 jiosition which leads, as a natural conse- 
 quence, to the scepticism of Huuie. On 
 the other bund, Reid, Beattie, and Oswald, 
 advocating the hitherto obscured element 
 of Feeling, maintained that the human 
 mind possesses immediate]}' in conscious- 
 ness principles of knowledge independent 
 of experience ; and a more cautious at- 
 temj^t was made by Richard Price to 
 shew that the Understanding, or Faculty of 
 Thought, a.s distinguished from the deduc- 
 tive faculty, is essentially diU'ereiit from 
 tbe faculty of sense, and is a source of 
 special representations distinct from those 
 of the senses. Yet, on the whole, all 
 these writei's, as regards the scientific 
 vindication of their teaching, were com- 
 pelled to place the foiuidation of the 
 immediate cognition of tlio higher truths 
 of reason in a Common Sense ; and the 
 assumption of this pretended source ne- 
 cessarily involved su.spicion and doubt 
 as regards the truth of the cognitions 
 derived from it. And so also Jacobi, if
 
 XVI 
 
 MEMORANDA FOR PREFACE. 
 
 wo except the negative, polemical side of 
 his teaching, wherein he certainly accom- 
 plished much, has advanced little or 
 nothing beyond his English predecessors 
 in laying a firm scientific t'oundatiou for 
 his own view ; though he was the first 
 among ourselves who, in the controvei'sy 
 with the disciples of Wolf and other cog- 
 nate schools, by the emiiloymont of the 
 terms /ec/tn// and belief, directed attention 
 to the necessity of acknowledging the 
 importance of immediate cognition and 
 its consciousness 
 
 "Although Jacobi's system, on account 
 of its vacillating language, and still more 
 on account of its intuitive narrowness and 
 subjective character, was not fitted to bene- 
 fit philosophy immediately, it had, not- 
 withstanding, a foundation of truth, which 
 could not long fail of producing iis effect. 
 Many soon became clearly convinced that 
 the Kantian philosophy also was liable to 
 the charge of onesidedness, and failed to 
 satisfy the requirements of the entire man : 
 they acknowledged that Jacobi, notwith- 
 standing the enthusiastic vehemence of his 
 decisions, had seized and brought to light 
 a principle of our mental life hitherto 
 marvellously overlooked, the discovery of 
 which would henceforth fill up a great 
 void in the culture of the age, and the 
 recognition of which was indisi^ensable to 
 the preservation and progress of philoso- 
 phy. Even men who could not directly 
 be classed as belonging to the school of 
 Jacobi, the cleai'est and most cautious 
 thinkers, acknowledged the importance of 
 the distinction between mediate and im- 
 mediate knowledge, and between the 
 mediate and immediate consciousness of 
 it; and although thej' would not concede 
 to Feeling an independent significance, 
 and were unable to assign to it a sure 
 psychological position, they at least saw 
 clearly, and proved conclusively, that the 
 j)0\ver and efficacy of this Feeling must 
 be a necessary condition of knowledge 
 antecedent to all determinate conceptions 
 and reasonings. Among these men may 
 be especially mentioiied the so - called 
 scefjtic, (who in his later writings is a 
 natural realist,) G. E. Schulze,* Bouter- 
 wek,+ and Gerlach. J 
 
 "Schulze, indeed, regards the Feelings as 
 the most obscure and variable phase of the 
 
 * Psych. Anthropol. ed. 2, § 151, pp. 259, 260; 
 Encycl. der philos, Wissensch. §§ 39, 115; Kritik 
 der theor. Philos. 1. p. 702-720 ; Uuber die 
 menschl. Erkenntniss, § 45-50, pp. 155-174. 
 
 t Lehrb. der philos. Wissensch. Apod. p. 
 15-80. 
 
 t Lehrb. der pliilo.s. Wissensch. i. § 48, p. 48. 
 
 mental life : he holds them to be incapable 
 of establishing or proclaiming anything ob- 
 jective, and hence to be useless as princi- 
 ples for the demonstration of truth ; but 
 he repeatedly asserts the existence in the 
 human consciousness of certain funda- 
 mental assumptions, of which, by the con- 
 stitution of our nature, we are unable arbi- 
 trarily to divest ourselves, and which have 
 a place in all natural science and in moral 
 and religious convictions. It is true that 
 Schulze did not penetrate to a complete 
 insight into the nature of demonstrative 
 knowledge and transcendental idealism ; 
 and hence, from the position of his natural 
 objective realism, he is unable to discover 
 that our ideal convictions can attain to an 
 equal certainty with the natural conviction 
 of knowledge based on intuition. Bouter- 
 wek, adhering more closely to Jacobi's 
 doctrine, speaks of the consciousness of 
 the original feeling of truth as the first 
 witness of certainty in all human convic- 
 tion ; but, like Jacobi, he seems to believe 
 in a perceptive power of the internal 
 sense, by which even demonstrative phi- 
 losophical cognitions may be realised in 
 
 consciousness Fries is the 
 
 first who, by opening a new path of 
 authropologico-critical inquiry, has com- 
 pletely and fully succeeded in organi- 
 cally uniting the immediate products of 
 Jacobi's philosophy with the results of the 
 Kantian criticism, and thus in exhibiting 
 in a clear and scientific light, from the 
 laws of the theory of man's mental life, 
 the relation of Knowledge to Belief, of the 
 natural and ideal aspect of the world, as 
 well as the important relation between the 
 feelmg and the conception of the truth. He 
 is the first philosopher in whose system 
 Feeling has won an independent and firmly 
 established position among the philoso- 
 phical convictions of the reason. " * — Ed.] 
 
 Merits of the Scottish School. 
 
 Their proclaiming it as a rule, 1°, That 
 the province of a preliminary or general 
 Logic (Neology) — the ultimate laws, &c., 
 of the human mind — should be sought 
 out and established; 2°, That once recog- 
 nised and given, they should be accept- 
 ed to govern philosophy, as all other 
 sciences. 
 
 With regard to the first, the Scottish 
 philosophers are not original. It is a 
 perennis philosophia, gravitated towards 
 
 * On the relation of the system of Fries to 
 that of Raid, see below, Note A, p. 798, No. 95 ; 
 and the references tliere given. — Ed.
 
 xMEMORANDA FOR PREFACE. 
 
 XVM 
 
 even by those who revolted against it. 
 (See Note A. ) The merit of the Scotti.sh 
 school is one only of degree, — that it is 
 more consistent, more catholic, and em- 
 bodies this pcrcnnis philosophia more 
 purely. [Its writers, however,] are them- 
 selves peccant in details, and have not 
 always followed out the spirit of their 
 own doctrines. 
 
 [With regard to the second,] Dr Reid 
 and Mr Stewart not only denounce as 
 absurd the attempt to demonstrate that 
 the original data of Consciousness are for 
 us the rule of what we ought to believe, 
 that is, the criteria of a relative — human — 
 subjective truth; but interdict as unphi- 
 losophical all question in regard to their 
 validity, as the vehicles of an absolute 
 or objective truth. 
 
 M. JonfFroy,* of course, coincides with 
 the Scottish philosophers in regard to 
 the former ; but, as to the latter, he 
 maintains, with Kaut, that the doubt is 
 legitimate, and, though he admits it to be 
 insoluble, he thinks it ought to be enter- 
 tained. Nor, on the ground on which 
 thej- and he consider the question, am I 
 disjjosed to dissent from his conclusion. 
 But on that on which I have now placed 
 it, I cannot but view the inquiry as in- 
 competent. For what is the question in 
 plain terms ? Simply,— Whether what our 
 nature compels us to believe as true and 
 real, be true and real, or only a consistent 
 illusion ? Now this question cannot be 
 philosophically entertained, for two rea- 
 sons. 1°, Because there exists a pre- 
 sumption in favour of the veracity of 
 our nature, which either precludes or 
 peremptorily repels a gratuitous supposi- 
 tion of its mendacity. 2°, Because we 
 have no mean out of Consciousness of 
 testing Consciousness. If its data are 
 found concordant, thej' mii.st be presumed 
 trustworthj' ; if repugnant, they are al- 
 ready proved unworthy of credit. Un- 
 less, therefore, the mutual collation of 
 the primary data of Consciousness be 
 held such an inquiry, it is, I think, mani- 
 festly incompetent. It is only in the case 
 of one or more of these original facts 
 being rejected as false, that the question 
 can emerge in regard to the truth of the 
 others. But, in reality, on this hypothesis, 
 the problem is already decided ; their 
 character for truth is gone ; and all sub- 
 sequent canvassing of their probability is 
 profitless speculation. 
 
 Kant started, like the philosophei's in 
 general, with the non-acceptance of the 
 
 • (Euvrca de Rcid, Preface, p. clxxxv.— Ed. 
 
 deliverance of Consciousness, — that wo 
 are immediately cognisant of extended 
 objects. This first step decided the des- 
 tiny of his philosophy. The external 
 world, as known, was, therefore, only a 
 pha;uomenou of the internal ; and our 
 knowledge in general only of self; the 
 objective only subjective ; and truth only 
 the harmony of thought with thought, not 
 of thought with things ; reality Only a 
 necessary illusion. 
 
 It was quite in order, that Kant should 
 canvass the veracity of all our inimary 
 beliefs, having founded his philosoijhy on 
 the presumed falseliood of one ; and an in- 
 quiry followed out with such consistency 
 and talent, could not, from such a com- 
 mencement, terminate in a difierent 
 result.* 
 
 Fichte evolved this explicit idealism — 
 
 Nihilism, t 
 
 Following the phantom of the Absolute, 
 Schelling rejected the law of Contradiction, 
 as Hegel that of Excluded Middle; J with 
 the result that, as acknowledged by the 
 former, the worlds of common sense and 
 of philosophy are reciprocally the converse 
 of each other. Did the author not see 
 that this is a rcductio ad ahsurdnm of phi- 
 losophy itself ] For, ex Jujputliesi, -philo- 
 sophy, the detection of the illusion of our 
 nature, shews the absurdity of natm-e; 
 but its instruments are only those of this 
 illusive nature. Why, then, is it not an 
 illusion itself? 
 
 The philosoph J' which relies on the data 
 of Consciousness may not fulfil the condi- 
 tions of what men conceit that a philo- 
 sophy should be : it makes no pretension 
 to any knowledge of the absolute — the 
 unconditioned — but it is the only philo- 
 sophy which is conceded to man below; 
 and if we neglect it, we must either re- 
 nounce philosophy or pursue an iynh fa- 
 tiius which will only lead us into quag- 
 mires. § 
 
 [Defects of the Scottish School.] 
 
 Scottish school too exclusive — intoler- 
 ant, not in spirit and intention, for Reid 
 
 * Reprinted from Lectures on Metaphysics, vol. 
 i, J). 35)9. From the riifovence below, p. 7-)fi a, 
 n. *, it appears tliat tliis qiie.stion w.'is intended 
 to be (liseussed in the Preface. — Ed. 
 
 t See below, p. 120, n. *, nnd 796 b.— Ed. 
 
 J See Lectures on Loyic, vol. 1. p. 90. — Ed. 
 
 § In the MS. follow references to the two 
 Sealigers, to Grotius, nnd to Cusa ; tlic List being, 
 through Bruno, the fadiei- of the modern Philo- 
 sophy of the Absolute. .\11 theso referenees are 
 given in full, Discussions, pp. 638-041.— Kd.
 
 XVUl 
 
 MEMORANDA FOR PREFACE. 
 
 and Stewart were liberal — but from not 
 taking higli enough ground, and studying 
 opinions with sufficient accuracy, and from 
 a sufficiently lofty point of view. 
 
 On the nature and domain of the philo- 
 sophy of mind. 
 
 Reid and Stewart do not lay it out jiro- 
 perly, though their practice is better than 
 their precept. They do not take notice 
 of the difference between mental and phy- 
 sical inquiry — that the latter is mere induc- 
 tive classification, the former more specula- 
 tive, secerning necessary from contingent. 
 But an element of thought being found 
 necessary, there remains a further process 
 — to ascertain whether it be, 1", by nature 
 or by education ; 2°, ultimately or deriva- 
 tively necessary ; 3°, positive or negative. 
 . . . . A law of nature is only got by 
 general induction ; a law of mind is got by 
 experiment — whether we can not think it; 
 e. g. cause in objective and subjective phi- 
 losophy. The progress of the two sciences 
 not parallel — error of )Stewart (Essays, p. 
 xiii.*) 
 
 An experimental analj^sis, but of differ- 
 ent kinds, is competent to physical and 
 mental science, besides the observation 
 common to both. To mental, the trying 
 what parts of a conci-ete thought or cog- 
 nition can be thought away, what cannot. 
 
 \_Further elevelopments srqiplementary to 
 the philosophy of the Scottish school, as re- 
 presented by Reid and Stewwrt.'] 
 
 [A. On the Principle of Common Sense.l 
 
 I would, with Leibnitz, t distinguish 
 truths or cognitions into those of Fact, or 
 of Perception, (external and internal), and 
 those of Reason. The truths or cognitions 
 of both classes rest on an ultimate and 
 common ground of a primary and inexpli- 
 cable belief. This ground may be called 
 by the names of Common Sense, of Fun- 
 damental or Transcendental Consciousness, 
 
 * Coll. Works, vol. v. p. 13. " The order 
 established in the intellectual world seems to be 
 regulated by laws i>erfectly analogous to those 
 which we trace among the phsenomena of the 
 material system; and in all our rl'Uosophical 
 inquiries, (to whatever subject they may relate,) 
 the progress of the mind is liable to be aflTected 
 by the same tendency to a prematm-e generalisa- 
 tion." On tliis passage, there is the following 
 marginal note in Sir W. Hamilton's copy : " Shew 
 how this analogy is vitiated by the fact that the 
 most general facts, being necessities of thought, are 
 among the first established. Existence, the last 
 in the order of induction, is the fii'st in the order 
 of ."—Ed. 
 
 t Nouveaux Essais, L. iv. ch. 2.— Ed. 
 
 of Fcelinf/ of Truth or Knowledge, of Na- 
 tural or Instinctive Belief. This, in itself, 
 is simply a fact, simply an experience, and 
 is purely subjective and purely negative. 
 Ic supports the validity of a proposition, 
 only on the fact that I find that it is im- 
 possible for mo not to hold it for true, to 
 suppose it therefoi'e not true — without 
 denying, in the one case, the veracity of 
 consciousness ; and, in the other, the pos- 
 sibility of thought; [without presuming] 
 that I am necessitated to hold the false 
 for the true, the unreal for the real, and 
 therefore that my intelligent nature is 
 radically mendacious. But this is not to 
 be gratuitously presumed ; therefore the 
 proposition must be admitted. But to 
 apply it to the two classes of truths. 
 
 I. Truths of Fact or of Perception (Ex- 
 ternal and Internal.) 
 
 Am I asked, for example, how I know 
 that the series of phgenomena called the 
 external world or the non-ego exists — 
 I answer, that I know it by external Per- 
 ception. But if further asked, how I 
 know that this Perception is not an il- 
 lusion — that what I perceive as the ex- 
 ternal world, is not merely a particular 
 order of phajnomena pertaining to the in- 
 ternal — that what I am conscious of as 
 something different from me, is not merely 
 self representing a not-self — I can only 
 answer, that I know this solely inasmuch 
 as I find that I cannot but feel, hold, or 
 believe that what I perceive as not-self, is 
 really presented in consciousness as not- 
 self. I can, indeed, in this, as in the case 
 of every other truth of Fact, imagine the 
 possibility of the converse — imagine that 
 what is given as a mode of not-self, may 
 be in reality only a mode of self. But this 
 only in imagining that my primary con- 
 sciousness deceives me; which is not to 
 be supposed without a ground. Now, the 
 conviction here cannot in propriety be 
 called Reason, because the truth avouched 
 by it is one only of Fact, and because the 
 conviction avouching it is itself onty ma- 
 nifested as a Fact. It may, however, be 
 well denominated Common Sense, Funda- 
 mental or Transcendental Consciousness. 
 Other examples may be taken from Me- 
 mory and its reality, Personal Identity, &c. 
 
 II. Truths of Reason. 
 
 Again, if I am asked, how I know that 
 every change must have its cause, that 
 every quality must have its substance, 
 that there is no mean between two contra- 
 dictories, &c., I answer, that I know it by 
 Reason, vods — Reason or vovs being a name 
 for the mind considered as the source, or as 
 the complement, of first princijjles, axioms, 
 native notions, koivoI or (pvcriKol tvvoiai.
 
 MEMORANDA FOR PREFACE. 
 
 xix 
 
 But if further asked, how I know that Rea- 
 son is not ilkisive — that this, or that first 
 principle may not be false — I can only an- 
 swer, that I know it to be true, solely inas- 
 much as I am conscious that I cannot but 
 feel, hold, believe it to be true, seeing that 
 I cannot even realise in imagination the 
 possibility of the convei'se. Now, this last 
 ground of conviction, in the conscious im- 
 potence of conceiving the converse, is not, 
 I think, so properly styled Reason, which 
 is more of a positive character, as Common 
 Sense, Fundamental Consciousness, &c. 
 This is shewn in the quotations from 
 Locke and Price. Note A, Testimonies, 
 Nos. 51, 78. 
 
 [The substance of these remarks on the 
 Priuciple of Common Sense, has been 
 already printed, in an abbreviated foi'm, 
 in Note A, p. 754. The present fragment, 
 which has the appearance of being an 
 earlier sketch of the same note, has been 
 inserted in this place, as containing a 
 somewhat fuller statement of an import- 
 ant distinction, which is perhaps liable to 
 be overlooked in the brief form in which 
 it was previously published. Though not 
 apparently designed for this Preface, it is 
 sufficiently cognate in matter to the pre- 
 ceding fragments, to be entitled to a place 
 with them. The following fragment, which 
 is marked " Preface," may be regarded as a 
 continuation of the same subject, being a 
 step towards that further analysis of the 
 Truths of Reason, in relation to the Phi- 
 losophy of the Conditioned, which the 
 Author regarded as his peculiar addition 
 to the philosophy of his predecessors. This 
 analysis will be found further pursued 
 in Notes H and T, and especially in the 
 Philosophical Appendix to the Discussions. 
 —Ed.] 
 
 [B. Stages in the method of Menial 
 Science.] 
 
 Three degrees or stages in the method 
 of mental science. 
 
 1°, When the mind is treated as matter, 
 and the mere Baconian observation and 
 induction applied. 
 
 2°, When the quality of Necessity is in- 
 vestigated, and the empii-ical and neces- 
 sary elements thus discriminated. (Here 
 Reid is honourably distinguished even 
 from Stewart, not to say Brown and other 
 British pliilosopliei's.) 
 
 3°, "When the necessity is distinguished 
 into two cla.sses — the one being founded 
 on a power or potency, the other upon an 
 impotence of mind. Hence the Philosophy 
 of the Conditioned. 
 
 [Testiinonics to the merits oj the BcMish 
 Philosophy, and of Reid as its founder.'] 
 
 1. — PouET. — Manuel de Philosophie par 
 Auguste Henri Matthias, traduit de I'Alle- 
 mand sur la troisieme edition, par M. H. 
 Poret, Professeiu- suppliant h, la Faculte 
 des Lettres, et Professeur de Philosophie 
 au College Rollin. Paris, 1837. 
 
 Preface du Traducteur. — 'II suffit d'a- 
 voir uue id(5e de I'dtat des etudes en France 
 pour veconnaitre que la philosophie ecos- 
 saise y est aujourd'hui naturalisee. Nous 
 la voyons defrayer 'h pen pres seule I'en- 
 seignement de nos colleges; sa langue 
 et ses doctrines ont passd dans la plu- 
 part des ouvrages elementaires qui se 
 publieut sur les matieres philosophiques ; 
 sa methode severe et circonspecte a 
 satisfait les plus difficiles et rassurd les 
 plus defiants, et en meme temps son 
 profond respect pour les croyauces mo- 
 rales et religieuses lui a concilie ceux 
 qui reconnaissent la vdrite surtout h, ses 
 fruits. Les penseurs prevoyants qui se 
 donncrent tant de soins pour I'introduire 
 parmi nous ont eu k se feliciter du succos 
 de leur efi'orts. La seule apparition de 
 cette philosophie si peu fastueuse suffit 
 pour mettre a terre le sensualisme ; une 
 docti'ine artificielle dut s'evanouir devant 
 la simple exposition des faits ; le sens in- 
 time fut retabli dans sa prerogative ; les 
 elements a priori de I'intelligence, si ridi- 
 culement honnis par Locke et son dcole, 
 reutrcrent dans la science dont on avait 
 prctendu les baunir, et y reprirent leur 
 place legitime. Cette espoce de restaura- 
 tion philosophique devait avoir ses con.s^ 
 quences : des questions assoupies, mais 
 non pas mortes, se r^veillerent ; les limites 
 arbitrairement posees a la connaissance 
 disparurent ; la philosophie retrouva son 
 domaine, et de nouveau les esprits s'effor- 
 cerent de le couqudrir. En gdudral, lo 
 bienfait des doctrines ecossaises importdes 
 en France, §'a dtd d'att'raiichir les intelli- 
 gences de tout prejugd d'ecole et de les 
 remettre en prdsence de la realite. Nul 
 doute que ce ne fut la I'indispcnsable con- 
 dition de tout progr5s ulterieur, et cette 
 condition indisjjcnsable, elles I'ont remplie 
 dans toute son dtendue. Aujoiud'iiui 
 meuie qu'elles ont portc ces i)remicrs 
 fruits, les bons eil'ets de ces doctrines ne 
 sont pas, nous le croyons, pres do s'epuiser, 
 et nous regarderions comme un dchcc h. la 
 prospdrite des dtudes philosophiques tout 
 ce qui tondrait h, en contrarier I'influonce.' 
 
 2. — Gaunier. — -Critique de la Philoso- 
 phie de Thomas Reid, Paris, 1840. 
 
 P. 112. — ' Demandcz a ce philosojihe 
 une distribution mdthodiquedesniatdriaux
 
 XX 
 
 MEMORANDA FOR PREFACE. 
 
 qu il a recueilli.s, unc adroite induction 
 qui des phduom^nes nous conduise &, un 
 petit uombre de causes, vous ne trou- 
 vercz ui cotte classification, ni cette ana- 
 lyse. Ce nctait pourtant pas la tache la 
 plus malaisde ; et le ddpit de lui voir 
 negliger co facile travail est ce qui nous a 
 mis la plume a la main. Mais ces matdri- 
 aux iuuombrables, ces milliers de phd- 
 nom5ncs si patiemment decrits, faut-il les 
 oublierl N'est-ce pas Reid qui nous a 
 montrS b, ne plus confoudre les percep- 
 tions des diflfcrents sens, et en particulier, 
 celles de la vue et du toucher ? Malgrd 
 quelques contradictions, n'est-ce pas chez 
 lui seul qu'on pent recontrer une tlidorie 
 raisonuable de la perception ? Oil trouver 
 une plus'savante exposition de la memoire 
 et des merveilles si varices qui presente 
 la suite de nos conceptions ? Ses essais 
 sur I'abstraction, le jugement, et le rai- 
 sonuement sont encore plus lumineux et 
 plus instructifs que les memes chapitres 
 dans I'admirable Logique de Port-Royal, 
 et les savants solitaires ont partagd la 
 faute de regarder ces operations de 
 I'esprit comme les actes d'autant de 
 facultes distiuctes. Enfin, avec quel pro- 
 fit et quel intdret ne lit-on pas les cha- 
 pitres sur le go(it intellectuel, sur les affec- 
 tions si varices qui se partagent notre ame, 
 sur le sens du devoir et sur la morale's 
 Avec tous ses ddfauts, I'ouvrage de Reid 
 otfrira longtemps encore la lecture la plus 
 instructive pour I'esprit, la plus ddlicieuse 
 pour le coeur, et la plus profitable pour la 
 philosophic.' 
 
 P. 118. — ' En presence des constructions 
 fantastiques de I'AUemagne, j'aime mieux 
 les materiaux dpars de I'Ecosse. Thomas 
 Reid est I'ouvrier laborieux, qui a peui- 
 blement extrait les blocs de la carriere, 
 qui a tailld les mats et les charpentes : vi- 
 enne I'architecte, il en construira des villes 
 et des flottes. L'AUemand est I'entrepre- 
 neur audacieux qui dans la hate de batir se 
 coutente de terre et de paille.' 
 
 3. — Remusat. — Essais de Philosoi^hie, 
 Paris 184-2, t. i. p. 250.—' La philosophic 
 de Reid nous parait un des plus beaux r6- 
 sultats de la metliode psychologique. Plus 
 approfondie, mieux ordonnde, elle pent de- 
 venir plus .systdmatique et plus complete ; 
 elle pent donner h, I'observation une forme 
 plus rationnelle. Sans doute elle n'est.pas 
 tout la vdrite philosophique ; mais dans 
 son ensemble elle est vraie, et nous croyons 
 qu'elle doit etre cousiddree par les dcoles 
 mod ernes comme la philosophie elemen- 
 taire de I'esprit humain.' 
 
 4. — Thdrot. — -Introduction a I'^^tude 
 de la Philosophie, Discours Preliminaire, 
 t. i. p. LXiv. Speaking of Reid's Essays — 
 
 ' L'drudition choisie et variee qu'il a su y 
 repandre, I'amour sincere de la vdritd qui 
 s'y montre partout, et la dignitd calme de 
 I'expressiou en rendent la lecture extreme- 
 ment attachante.' 
 
 5. — Cousin.— [Cours d'Histoire de la 
 Philosophie Morale au dix-huiti5me Sidcle, 
 seconde partie, publide par MM. Dantou 
 et Vacherot, Paris, 1840], p. 241 sq.* 
 
 ' There is a final merit in the doctrine 
 of the Scottish philosopher, which it is 
 impossible too highly to extol. He has 
 done better than ruin the hypotheses 
 which had shaken all the bases of human 
 belief; in fixing with precision the limits 
 of science, he has destroyed for ever the 
 spirit itself which had inspired them. The 
 philosophy which Reid combated had not 
 understood that there were facts inex[)li- 
 cable, facts which carry with them their 
 own light ; and had therefore gone, in 
 quest of a principle of explanation, into a 
 foreign sphere. It is thus that to explain 
 the pha3nomena of jserception, of mem- 
 ory, of imagination, recourse was had to 
 images from the external world ; the phse- 
 nomena of the soul were represented as 
 the effects of sensible impressions, them- 
 selves resulting from a contact between 
 the mind and the body. Reid has laid 
 down the true criterium, in virtue of which 
 we can always recognise the point at which 
 an attempt at explanation ought to stop, 
 when he says : — Facts simple and x>rimi- 
 tive are inexplicahle. It is thus that he 
 has cut short those hypotheses, those pre- 
 sumptuous theories, which history has 
 consigned for ever to the romances of 
 Metaphysic. 
 
 ' In the meanwhile, it remains for me 
 to consider, whether the i-emedy be not 
 excessive, and whether the philosophy of 
 Reid, in ruining the metaphysical hypo- 
 theses, has not proscribed the metaphysi- 
 cal spirit itself. But before entering 
 upon the question, it is requisite to pre- 
 mise, that even if this be done by Reid, 
 still there is nothing in the proceeding 
 at which criticism ought to take offence. 
 His mission was to proclaim the applica- 
 tion of the experimental method to the 
 philosophy of the human mind, on the 
 ruins of the hypotheses which had issued 
 from the Cartesian school ; this mission he 
 has completely fulfilled, for he has purged 
 philosophy, one after another, of the 
 theory of ideas, of the desolating scepticism 
 
 * This passage is given in a translation found 
 among Sir W. Haicilton's papers. The other 
 testimonies have been added from his extracts 
 and references. — Ed.
 
 MEMORANDA FOR PREFACE. 
 
 XXI 
 
 of Hume, of the idealism of Berkeley, of 
 the demonstrations of Descartes ; he has 
 thus made a tabula rasa. Were it then 
 the fact, that the abuse of the metaphysical 
 spirit, and the spectacle of the aberrations 
 into which this spirit has betrayed the 
 human mind, had carried Reid to pro- 
 nounce its banishment from science, for 
 this we ought no more seriously to re- 
 proach him, than we should condemn 
 Bacon for his pi-oscriptiou of the Syllog- 
 ism, of which the Schoolmen had made so 
 flagi-ant an abuse. My intention, there- 
 fore, in touching on this delicate point, is, 
 far less to evince the too empirical char- 
 acter of the philosophy of Reid, than to 
 relieve a great and noble science from 
 the unjust contempt to which it has been 
 exi:)osed from the i^hilosophers both of the 
 school of Bacon and of the Scottish school. 
 
 ' But let us first see, how far Reid's 
 neglect of Metaphysic has extended. — Ac- 
 cording to him, to explain a fact is to 
 carry it up into a fact more simple ; so 
 that the explanatory principle is of the 
 same nature as the fact explained, nor, in 
 our explanation of facts, is it ever neces- 
 sary for us to transcend experience. I 
 admit the truth of this definition for a 
 certain number of the sciences which 
 ought not to transgress the bounds of ob- 
 servation : thus in Physics, in Natural His- 
 torj-, in P.sychology even, the explanation 
 of the fact can possess no other character, 
 can i^ropose no other aim. But I believe 
 the human mind goes farther ; the ex- 
 planation which consists in the connecting 
 one fact to another more simple does not 
 suffice for it, nor does it even recognise 
 this as a veritable explanation. To ex- 
 plain, to explicate, in the strict propriety 
 of lanjjuacjo, is to reduce that which is to 
 that which ouf/ht to be, in other words, 
 to connect a fact to a principle. Reid, 
 therefore, in the view he takes of the 
 explanation of facts, has banished from 
 science the research of principles, of the 
 nece.s.sary causes and reasons of things, — 
 that is, precisely, metaphysical speculation. 
 
 ' On the other hand, to distinguish 
 philosophy from the sciences which have 
 nature for their object, he defines it — the 
 science of the human mind; he thus con- 
 siders philosophy as a science no less 
 special than the others, which is only dis- 
 criminated from them by the nature of 
 its object, and wiiich, moreover, has witii 
 them tlie same method and the same end. 
 The same method : for, like tiie natui-al 
 sciences, it observes ; only the facts which 
 it observes are irnrnaterial. The same 
 end : for it proposes the discovery of laws, 
 like the sciences of nature ; the only dif- 
 
 ference lying in the nature of these laws. 
 As to that general and synthetic science, 
 which applies itself to all, and to which 
 no matter comes amiss, which is distin- 
 guished from other sciences, not by the 
 character of its object but by the elevated 
 point of view from which it contemplates 
 the universe of things, which styles itself 
 philosophy of Nature, philosophy of Mind, 
 philosophy of History, according to the 
 limitation of the object which for the 
 moment it considers, — of such a science 
 Reid does not appear to have even sus- 
 pected the existence. 
 
 ' In fine, we ought not to forget that 
 Reid is a partisan of the Baconian method, 
 which he has extended from thg sciences 
 of nature to the science of mind. Now, 
 as is well known, Bacon had a proud con- 
 tempt of Metaphysic, and names it only to 
 deride it, or to shew that in retaining the 
 word, he rejects the thing. Accordingly, 
 in his classification of the sciences, he 
 reduces Metaphysic to the mere science 
 of the immutable and universal forms of 
 nature, that is to say, to a transcendental 
 physics; while subsequently, in his Novum 
 Organum, there is no mention of it at aU. 
 Reid, who inherited from Bacon his 
 method, inherited likewise fiom him his 
 contempt of Metajjhysic; and, with Reid, 
 the whole Scottish school. 
 
 ' Once more I repeat, the reaction of 
 the experimental philosophy, so much and 
 so long oppressed by speculation, is excus- 
 able in Reid as in Bacon, because on their 
 part it was natural and almost necessary ; 
 but in the present day, when this philoso- 
 phy has everywhere triumphed over the 
 obstacles which the spirit of system, the 
 prejudices and the authority of the past, 
 had accumulated in its path,- — in the pre- 
 sent day, when this philosophy in its turn 
 oppresses Metaphysic, and would, if it 
 could, exclude it from the domain of 
 science, it may not be unimportant briefly 
 to shew, that Metaphysic also has its 
 titles, and its legitimate place in the cj'cle 
 of human knowledge. 
 
 ' In the first place, it is a very ancient 
 science ; under definitions the most di- 
 verse, it has always appeared as the 
 science of principles. Until the eighteenth 
 century, it has never for a moment quit- 
 ted the philosophic stage, and on that 
 stage has never ceased to occupy the most 
 distiiiguislied part. The rea.-ion of this 
 preeminence was very simple ; for to 
 Metaphysic was confided the task of re- 
 solving the most extensive, arduou.^, and 
 important problems : Metaphysic alone 
 spoke of God and his attributes, of the 
 iniivorse considered in its totality and ita
 
 xxu 
 
 MEMORANDA FOR PREFACE. 
 
 laws, of the human soul and of its destiny; 
 Metaphysic alone shewed to each faculty 
 the end in view for its activity, to the im- 
 agination the ideal of the beautiful, to the 
 will the ideal of tlie good, to the intelli- 
 gence the ideal of the true. Since the 
 empirism of the last century, dominant 
 in France and England, has relegated 
 Metaphysic to the region of chimseras, 
 science rarely agitates those mighty pro- 
 blems, and if perchance it moots them, it 
 does so with a timidity and weakness 
 which make us regret ohat powerful im- 
 pulse of the metaphysical genius which 
 alone is competent to handle and resolve 
 these formidablo questions. Why then 
 has it been repudiated by science] Is it 
 only proper to generate magnificent ro- 
 mances 1 Is it that Metaphysic is without 
 a basis 1 
 
 ' To judge of it by the objections of its 
 adversaries and by the unreflective en- 
 thusiasm of its partisans, to judge of it 
 especially by the strange forms in which 
 imagination has been pleased to clothe it, 
 it would seem that Metaphysic is a philo- 
 sophy mysterious and almost superhuman, 
 which descends from another world, and 
 which has nothing in common with the 
 positive and natural methods of science. 
 There is nothing more false. Metaphysic, 
 like the other sciences, has its roots in the 
 nature of the mind. If the sciences of 
 fact repose in observation, if the abstract 
 sciences are founded upon reasoning, Me- 
 taphysic has for its basis the conceptions 
 of reason, as well pure as in combination 
 with the data of experience. I say the 
 conceptions of reason, which I distinguish, 
 and which every observer of the acts of 
 intelligence may distinguish, from the fan- 
 tastic or arbitrary creations of imagination. 
 When on occasion of an existence finite, 
 contingent, relative, individual, attested 
 by experience, I conceive the infinite, the 
 necessary, the absolvite, the universal ; 
 when rising from the phajnomena which 
 the univei'se presents to my observation, 
 I contemplate the great laws of this uni- 
 verse, those laws which constitute the 
 harmony of its movements, the order and 
 the beauty of its plan ; when retiring 
 within the limits of my proper nature, I 
 connect the phsenomena, so various and 
 80 mutable, in which it is manifested, to 
 a principle, simple, identical, and immut- 
 able in essence, — I neither imagine, nor 
 dream, nor fabricate ; I conceive. My 
 conception is an act of my mind, necessary 
 and legitimate as the very simplest percep- 
 tion. No intelligent being has a right 
 to contest the authority of any faculty 
 whatever of intelligence, and it is lament- 
 
 able to see the highest and divinest of its 
 functions treated with contempt.' 
 
 6. — JoDFFROY. — (Euvres Completes de 
 Thomas Reid, Paris, 183S. 
 
 Preface, pp. cc. cci. — ' S'il est un service 
 et un service Eminent que les Ecossais aient 
 rendu h, la philosophic, c'est assur^ment 
 d'avoir etabli une fois pour toutes dans les 
 esprits, et de manifere 3, ce qu'elle ne puisse 
 plus en sortir, I'idee qu'il y a une science 
 d'observation, une science de faits, d, la 
 maniere dout I'entendent les physiciens, 
 qui a I'esprit humain pour objet et le sens 
 intime pour instrument, et dont le r^- 
 sultat doit etre la determination des lois 
 de I'esprit, comme celui des sciences 
 physiques doit etre la determination des 
 lois de la matifere. Les philosophes ecos- 
 sais ont-ils eu les premiers cette idee ? 
 Non, sans doute, si par avoir une id^e 
 on entond simplement en ^mettre d'au- 
 tres qui la contiennent ; & le prendre 
 ainsi plusieurs philosophes I'avaient eue 
 avant eux, et, pour ne citer que les 
 plus C^l^bres, on la trouve dans Locke et 
 dans Descartes. Mais si par inventer une 
 idee on entend non j^as seulement en 
 concevoir le germe, mais la saisir en elle- 
 meme dans toute sa v^rit^ et son ^ten- 
 due, mais en voir la portde et les conse- 
 quences, mais y croire, mais la pratiquer, 
 mais la precher, mais la mettre dans une 
 telle lumiore qu'elle p^netre dans tons les 
 esprits et qu'elle soit d^sormais acquise 
 d'une manidre definitive h I'intelligence 
 humaine, on pent dire avec verity que, 
 I'idee dont il s'agit, les Ecossais I'ont eue 
 les premiers et qu'ils en sont les v^ritables 
 inventeurs. ' 
 
 P. cciv.-ccvi. — ' C'est Ih, en effet le vrai 
 titre, le titre Eminent des philosophes Ecos- 
 sais h I'estime de la posterity et le principal 
 service qu'ils aient rendu h la philosophic. 
 C'est un fait qu'avant eux, ui I'idee de 
 cette science ainsi nettemeut demelee, ni 
 I'idde de la m^thode vraie ;i y appliquer, 
 ni I'exemple d'une application rigoureuse 
 de cette m^thode, n'existaient; e'en est 
 lui autre que depuis eux tout cela existe 
 et que c'est h, eux qu'on le doit. Qu'ils 
 soient trop restcJs dans les limites de cette 
 science, et, faute d'en etre assez sortis, 
 qu'ils n'en aient pas vu toute la portde, ni 
 I'ensemble des liens qui, en y rattachant 
 toutes les sciences philosophiques, en 
 forment le point de depart et la racine de 
 la moitie des connaissances humaines, cela 
 est vrai, et nous I'avons montre; que les 
 vues historiques qui les ont conduits h, 
 I'idde de cette science manquent souvent 
 d'etendue et de justesse, et que dans la 
 determination de la methode, des limites 
 et des conditions de la science meme, ils
 
 MEMORANDA FOR PREFACE. 
 
 XXIU 
 
 n'aient pas toujours ni bien vii, ni assez 
 vu, c'est ce qui est encore vrai et ce que 
 nous avous egalement montre ; niais tou- 
 jours est-il que rhonneur de Tavoir cr^ee 
 est k eus, et que, quaud I'histoire voudra 
 marquer I'epoque ou la science de I'esprit 
 humain a veritablement ete couQue telle 
 qu'elle doit I'etre, elle sera forcee d'indi- 
 quer celle ou les philosophes ecossais ont 
 ^crit. 
 
 ' Une seconde id^e qui reste grav^e 
 dans I'esprit quand on a lu les philosophes 
 ^cossais, et dont on peut dire, comme de 
 la prec^dente, qu'ils I'out mise au monde, 
 quoique plusieurs philosophes, et Locke 
 en deruier lieu, I'eusseut indiqu^e, c'est 
 que la couuaissance de I'esprit humain et 
 de ses lois est la condition de solution de 
 la plupart des questions dont la philo- 
 sophic s'occupe, de maniere que pour r^- 
 soudre ces questions il faut avant tout 
 acquerir cette conuaissance, et qu'elles ne 
 peuvent etre resolues que pai' hypothese 
 tant qu'on ne la possede pas. Nous avons 
 montr^ que cette idee n'etait que le germe 
 d'une idee plus grande que les Ecossais 
 n'ont saisie qu'k moitie, h savoir que toutes 
 les sciences philosophiques dependent de 
 la psychologie, parce que toutes les ques- 
 tions qu'elles agitent viennent se resoudre 
 dans la connaissance des ph^nom^ues spi- 
 rituels, et que c'est Ih le caractere com- 
 mun qui unit toutes ces sciences eutre 
 elles, qui en constitue I'unite, et les dis- 
 tingue des sciences phjsiques. Nous 
 avons ajoute que si les Ecossais s'^taient 
 eleves jusqu'h, cette idee, h la gloire d'a- 
 voir fond^ la science de I'esprit humain 
 ils auraient ajout(^ celle d'avoir fix^ I'id^e 
 de la philosophie et d'avoir organist cette 
 moiti^ de la connaissance humaine. Mais 
 si cette conception est rest^e imparfaite 
 dans leur esprit, il n'en est pas moius vrai 
 qu'elle s'y est suffisamment d^veloppde 
 pour imprimer h la philosophie dcossaise 
 une direction originale ct qui est selon 
 nous celle-lbi meme que la philosophie doit 
 suivre. Subordonner toute recherche phi- 
 losophique a la psychologie, sur ce fonde- 
 ment que toute question philosophique a 
 Ba solution dans quelques lois do la nature 
 spirituelle, comme toute question physique 
 a la sienne dans quelques lois de la na- 
 ture physique, voilb, en rdalitd ce que les 
 
 Ecossais ont fait, et le principe qui plane 
 sur toute leur philosophie, qui I'anime, 
 qui la dirige, et dont on reste pdndtr^ 
 quand on I'a 6tudi^e. La methode phi- 
 losophique des Ecossais n'est autre chose 
 qu'uue consequence de ce principe; et 
 nou-seulemeut ils ont prouv^ la verity de 
 ce principe pour un grand nombre de 
 questions philosophiques et pour les plus 
 importantes, mais ils I'ont constamment 
 pratiqud. ' 
 
 Pp. ccvii., ccviii. — ' Avant et depuis les 
 Ecossais aucun autre systeme n'ofFre cette 
 constiniction de la science ; elle leur appar- 
 tieut en propre, et c'est la le second service 
 qu'ils ont rendu k la philosophie. lis ont 
 f ondd la science de I'esprit humain, c'est le 
 premier ; apres en avoir fixd I'idee, ils ont 
 fait de cette science le point de ddpart de la 
 philosophie et sont venus chercher dans ses 
 donnfes la solution scientifique de toute 
 question, c'est Ik le second. 
 
 ' Une troisi^me idde qui n'est moius 
 importante ni moins propre aux Ecossais 
 que les prdcedentes, c'est I'assimilation 
 complete des recherches philosophiques 
 et des recherches physiques, fondee sur 
 ce principe que les unes et les autres ont 
 Egalement pour objet la connaissance d'une 
 partie des oeuvres de Dieu, et qu'il n'y 
 a pas deux manieres de connaltre les 
 oeuvres de Dieu, mais une seule, qui s'ap- 
 plique k la solution des questions philo- 
 sophiques comme k celle des questions 
 physiques.' 
 
 P. ccxiii. — ' En prouvant cette simili- 
 tude, ils dissipent la superstitieuse ob- 
 scurity qui entoure les recherches philoso- 
 phiques; ils les ram^nentaux simples con- 
 ditions, a la simple nature, 3, la simple 
 methode de toutes les recherches scientifi- 
 quos; ils montrent I'erreur constante des 
 philosophes qui ont mdconnu cette v(5rit(5; 
 ils expliquent par cette erreur la destinde 
 mlaheureusedecesrecherches;ilsrassurent 
 ainsi les esprits que cette destinco eloig- 
 nait de s'en occuper, et les rappellent a la 
 philosophie en la mettant dans une voio 
 nouvelle et cepcndant dprouvee, dans la 
 grande voie qu'indiquent les lois do I'en- 
 tendement, qu'ont suivie toutes les sci- 
 ences, et par laquelle I'esprit humain est 
 ai'rive k toutes les verites qui font sa puis- 
 sance et sa gloire. '
 
 ACCOUNT 
 
 OF 
 
 THE LIFE AND WRITINGS 
 
 OE 
 
 THOMAS REID, D.D., F.R.S.E., 
 
 I.ATE PROFESSOR OF MORAL PHILOSOPHV IN THE UNIVERSITY OF GLASGOW. 
 
 BY 
 
 DUGALD STEWART, Esa., F.R.SS L. & E., 
 
 PROFESSOR OF MORAL PHILOSOPHY IN THE UNIVERSITY OF EDINBURGH. 
 
 BEAD AT DIFFERENT MEETINGS OF THE ROYAL SOCIETY OF EDINBUROH, 
 
 PUBLISHED IN 1803.
 
 ACCOUNT 
 
 OP 
 
 THE LIFE AND WRITINGS 
 
 OF 
 
 THOMAS REID D.D 
 
 SECTION I. 
 
 FROM DR REiD's BIRTH TILL THK DATE OF 
 HIS LATEST PUBLICATION. 
 
 The life of which I am now to present to 
 the Royal Society a short account, aithouiih 
 it fixes an era in the history of modern 
 philosophy, was uncommonly barren of 
 tho-e incidents which furnish materials for 
 bioj:;raphy — strenuously devoted to truth, 
 to virtue, and to the best interests of man- 
 kind, but spent in the obscurity of a learned 
 retirement, remote from the pursuits of 
 ambition, and with little solicitude about 
 literary fame. After the agitation, however, 
 of the political convulsions which Europe 
 has witnessed for a course of years, the 
 simple record of such a life may derive an 
 interest even from its uniformity ; and, 
 when contrasted with the events of the 
 passing scene, may lead the thoughts to 
 some views of human nature on which it is 
 not ungrateful to repose. 
 
 Thomas Reid, D.D., late Professor of 
 Moral Philosophy in the University of Glas- 
 gow, was born, on tlie 20th of A])ril 1710, 
 at Strachan, in Kincardineshire, a country 
 parish, situated about twenty miles from 
 Aberdeen, on the north side of the Gram- 
 pian mountains. 
 
 II is father, the Jiav. Lewis Roid, was 
 minister of this parish for fifty years. He 
 was a clergyman, according to his son's 
 account of hiui, respected by all who knew 
 him, for his piety, jirndonce, and benevo- 
 lence ; inhfritin^' from his ancestors (most 
 of whom, from the time of the Protestant 
 establishmoiif, had been ministers of the 
 Church of Scotlan i) that purity and sim- 
 plicity of manners which became his station ; 
 
 and a love of letters, which, without attract- 
 ing the notice of the world, amused his 
 leisure and dignified his retirement. 
 
 For some generations before his time, a 
 propensity to literature, and to the learned 
 professions — a propensity which, when it 
 has once become characteristical of a race, 
 is peculiarly apt to be ]5ropagated by the 
 influence of early associations and habits — 
 may be traced in several individuals among 
 his kindred. One of his ancestors, .James 
 Roid, was the first minister of Banchory- 
 Ternan after the Reformation, and trans- 
 mitted to four sons a predilection for those 
 studious habits which formed his own llap- 
 piness. He was himself a younger son of 
 ]Mr Reid of Pitfoddels, a gentleman of a very 
 ancient and respectable family in the county 
 of Aljgrdeen. 
 
 .Tames Reid was succeeded as minister of 
 Banchory by his son Robert. Another 
 son, Thomas, rose to considei-able distinc- 
 tion, both as aphilosojiher and a poet ; and 
 seems to have wanted neither ability nor 
 inclination to turn his attainments to the 
 best advantage. After travelling over 
 Europe, and maintaining, as was the cus- 
 tom of his age, ]iublic disputations in seve- 
 ral universities, he collected into a volume 
 the theses and dissertations which had been 
 the subjects of his literary contests ; and 
 also published some Latin poems, wliich 
 may be found in the collection entitled, 
 " Delitiee Pi'dtarum Scntorvm." On his 
 return to his native country, he fixed his 
 residence in London, wliere he was ap- 
 pointed secretary in the Greek and Latin 
 tongues to King .Tames T. of Eitg and," 
 and lived in habits of intimacy with some 
 
 * Whose English w-rks ho, along wiih the.learned 
 Patrick YouiiR, translated into Latin.— I!.
 
 ACCOUNT OF THE LIFE AND WRITINGS 
 
 of the most distinguished characters of that 
 period. Little more, I beheve, is known 
 of Thomas Keid's history, excepting that 
 he bequeathed to the INIarischal College of 
 Aberdeen a curious collection of Ixioks and 
 manuscripts, with a fund for establishing a 
 salary to a librarian. 
 
 Alexander Reid, the third son, was physi- 
 cian to King Charles I., and published 
 several books ou surgery and medicine. 
 The fortune he acquired in the course of 
 his practice was considerable, and enabled 
 him (beside many legacies to his relations 
 and friends) to leave various lasting and 
 honourable memorials, both of his benevo- 
 lence and of his attachment to letters. 
 
 A fourth son, whose name was Adam, 
 translated into English Buchanan's His- 
 tory of Scotland. Of this translation, 
 which was never published, there is a 
 manuscript copy in the possession of the 
 University of Glasgow. 
 
 A grandson of Robert, the eldest of these 
 sons, was the third minister of Banchory 
 after tlie Reformation, and was great- 
 grandfather of Thoma.s Reid, the subject of 
 this memoir." 
 
 The particulars hitherto mentioned, are 
 stated on the authority of some short 
 memorandums written by Dr Reid a few 
 weeks before his death. In consequence 
 of a suggestion of his friend, Dr Gregory, 
 he had resolved to amuse himself with col- 
 lecting such facts as his papers or memory 
 could supply, with respect to his life, and 
 the progress of his studies ; but, unfortun- 
 ately, before he had fairly entered on the 
 subject, his design was interrupted by hi? 
 last illness. If he had lived to complett 
 it, I might have entertained hopes of pre- 
 senting to the public some details with 
 respect to the history of his opinions and 
 si>eculations on those important subjects to 
 which he dedicated his talents — the most 
 interesting of all articles in the biography 
 of a philosopher, and of which it is to be 
 lamented that so few authentic records are 
 to be found in the annals of letters. All 
 the information, however, which I have 
 derived from these notes, is exhausted in 
 the foregoing pages ; and I must content 
 myself, ia the continuation of my narrative, 
 with those indirect aids which tradition, 
 and the recollection of a few old acquaint- 
 ance, afford ; added to what I myself have 
 learned from Dr Reid's conversation, or col- 
 lected from a careful perusal of his writings. 
 
 His mother, Margaret Gregory, was a 
 daughter of David Gregory, Esq. of Kin- 
 nairdie, in Banffshire, elder brother of 
 James Gregory, the inventor of the reflect- 
 ing telescope, and the antagonist of Huy- 
 ghens. She was one of twenty-nuie children ; 
 
 *■■ Note A. 
 
 the most remarkable of whom was David 
 Gregory, Savilian Professor of Astronomy 
 at Oxford, and an intimate friend of Sir 
 Isaac Newton. Two of heryounger brothers 
 were at the same time Professors of Mathe- 
 matics — the one at St Andrew's, the other 
 at Edinburgh — and were the first persons 
 who taught the Newtonian philosophy in 
 our northern universities. The hereditary 
 worth and genius which have so long dis- 
 tinguished, and which still distinguish, the 
 descendants of this memorable family, are 
 well known to all who have turned their 
 attention to Scottish biography ; but it is 
 not known so generally, that, tlirough the 
 female line, the same characteristical endow- 
 ments have been conspicuous in various 
 instances ; and that to the other monuments 
 which illustrate the race of the Gregories, 
 is to be added the Fhilosophy of Reid. 
 
 With respect to the earlier part of Dr 
 Reid's life, all that I have been able to 
 learn amounts to this : — That, after two 
 years spent at the parish school of Kincar- 
 dine, he was sent to Aberdeen, where he 
 had the advantage of prosecuting his class- 
 ical studies under an able and diligent 
 teacher ; that, about the age of twelve or 
 thirteen, he was entered as a student in 
 Marischal College ; and that his master in 
 philosophy for three years was Dr George 
 Turnbull, who afterwards attracted some 
 degree of notice as an author ; particularly 
 by a book entitled, " Principles of Moral 
 Philosophy ;" and by a voluminous treatise 
 (long ago forgotten) on " Ancient Paint- 
 ing."* The sessions of the College were, 
 at that time, very short, and the educa- 
 tion (according to Dr Reid's own account) 
 slight and superficial. 
 
 It does not appear, from the information 
 which I have received, that he gave any 
 early indications of future eminence. His 
 industry, however, and modesty, were con- 
 spicuous from his childhood ; and it was 
 foretold of him, by the parish schoolmaster, 
 who initiated him in the first principles o. 
 learning, " That he would turn out to be 
 a man of good and well-wearing parts ;" a 
 prediction which touched, not unhappily, 
 on that capacity of " patient thought" 
 which so peculiarly characterised liis philo- 
 sophical genius. 
 
 His residence at the University was pro- 
 longed beyond the usual term, in conse- 
 quence of his appointment to the office oi 
 librarian, which had been endowed by one 
 of his ancestors about a century before. 
 The situation was acceptable to him, as it 
 afforded an opportunity of indulging his 
 passion for study, and united the charms 
 of a learned society with tlie quiet of an 
 academical retreat. 
 
 * Note B.
 
 OF THOMAS llEID, D.D. 
 
 5 
 
 During this period, he formed an hitiniacy 
 with John Stewart, afterwards Professor of 
 ^Mathematics in JNlarisclial College, and 
 author of " A Commentary on Newton's 
 Quadrature of Curves." His predilection 
 for mathematical pursuits was confirmed 
 and strengthened by this connection. I have 
 often heard him mention it with nmch 
 pleasure, while he recollected the ardour 
 with which they both prosecuted these fas- 
 cinating studies, and the lights which they 
 imparted mutually to each other, in their 
 first perusal of the " Principia,'''' at a time 
 when a knowledge of the Is^ewtonian dis- 
 coveries was only to be acquired in the 
 writings of their illustrious author. 
 
 In 1736, Dr Reid resigned his office of 
 librarian, and accompanied Mr Stewart on 
 an excursion to England. They visited 
 together London, Oxford, and Cambridge, 
 and were introduced to the acquaintance of 
 many persons of the first literary eminence. 
 His relation to Dr David Gregory procured 
 htm a ready access to IMartin Folkes, whose 
 house concentrated the most interesting 
 objects which the metropolis had to ofl'er to 
 his curiosity. At Cambridge he saw Dr 
 Bentley, who delighted liim with his learn- 
 ing, and amused him with his vanity ; and 
 enjoyed repeatedly the conversation of the 
 blind mathematician, Saunderson — a pheno- 
 menon in the history of the human mind to 
 which he has referred more than once in 
 his philosophical speculations. 
 
 AVith the learned and amiable man who 
 was his companion in this journey, he main- 
 tained an uninterrupted friendship tiU 17C6, 
 w hen Mr Stewart died of a malignant fever. 
 His death was accompanied with circum- 
 stances deeply afflicting to Dr Reid's sensi- 
 bility ; the same disorder proving fatal to 
 his wife and daughter, both of whom were 
 buried with him in one grave. 
 
 In 1737, Dr Reid was presented, by the 
 King's College of Aberdeen, to tlie living of 
 New-Machar, in the same county ; but the 
 circumstances in which he entered on his 
 preferment were far from auspicious. The 
 intemperate zeal of one of his predecessors, 
 and an aversion to the law of patronage, had 
 so inflamed the minds of his parishioners 
 against him, tliat, in the first discharge of 
 liLs clerical functions, he had not only to en- 
 counter the most violent opposition, but was 
 exposed to personal danger. His unwearied 
 attention, liowever, to the duties of his 
 office, the niiMness and forlioarance of his 
 temper, and tlie active spirit of his humanity, 
 soon overcame all these prejuilices ; and, 
 not many years aft<'rward8, when he was 
 called to a different situation, the same per- 
 sons who had suttered tlieniselves to be ho 
 far misled as to take a share i)i the outrages 
 againt-t him, followed him, on his departure, 
 with their blessings and tears. 
 
 Dr Reid's popularity at New-Machar (as 
 I am informed by the respectable clergy- 
 man* who now holds that living) increased 
 greatly after his marriage, in 1740, with 
 Elizabeth, daughter of his uncle, Dr George 
 Reid, physician in London. The aecom- 
 modatmg manners of this excellent woman, 
 and her good offices among the sick and 
 necessitous, are still remembered with gra- 
 titude, and so endeared the family to the 
 neighbourhood, that its removal was re- 
 garded as a general misfortune. The simple 
 and affecting language in which some old 
 men expressed themselves on this subject, 
 in conversing with the present minister, 
 deserves to be recorded :— " We fought 
 ayainst Dr Reid when he came, and would 
 have fought for him when he went away. " 
 
 In some notes relative to the earlier part 
 of his history, which have been kindly com- 
 municated to me by the Rev. Mr Davidson, 
 minister of Rayne, it is mentioned, as a 
 proof of his uncommon modesty and diffi- 
 dence, that, long after he became minister of 
 New-Machar, he \\as accustomed, from a 
 distrust in his own powers, to preach the 
 sermons of Dr Tillotson and of Dr Evans. 
 I have heard, also, through other channels, 
 that he had neglected the practice of com- 
 position to a more than ordinary degree in 
 the earlier part of his studies. The fact is 
 curious, when contrasted with that ease, 
 perspicuity, and purity of style, which he 
 afterwards attained. From some informa- 
 tion, however, which has been lately trans- 
 mitted to tne by one of his nearest relations, 
 I have reason to believe that the number 
 of original discourses which he wrote while 
 a country clergyman, was not inconsider- 
 able. 
 
 The satisfaction of his own mind was 
 probably, at this period, a more powerful 
 incentive to his philosophical researches, 
 tlian the ho]ie of being able to instruct the 
 world as an author. But, whatever his views 
 were, one thing is certain, that, during liis 
 residence at New-Machar, the greater part 
 of his time was spent in the most intense 
 study; more particularly in a careful exami- 
 nation of the laws of external perception, 
 and of the other principles which form the 
 groundwork of human knowledge. His 
 chief relaxations were gardening and botany, 
 to both of which pursuits he retained liis 
 attachment even in old age. 
 
 A paper which he jjublishcd in the Phi- 
 losoj)hical Transactions of the Royal Society 
 of London, for the year \'i'M>, att'ords some 
 light with respect to the jirogiess of his 
 sjieculations about this period. It is en- 
 titled, " An Essay on Quantity, occasioned 
 by reading a Treatise in which Simple and 
 Comnound Ratios are anplied to Virtue and 
 
 • 'I'ho Rev. Willixm Strunacn.
 
 6 
 
 ACCOUNT OF THE LIFE AND WRITINGS 
 
 Merit ;" and sliewa plainly, by its contents, 
 that, althouj^li he had not yet entirely re- 
 linquished the favourite researches of his 
 youth, he was beginning to direct his thoughts 
 to other objects. 
 
 The treatise alluded to in the title of this 
 paper, was manifestly the " Inquiry into 
 the Orij,'in of our Ideas of Benuly and Vir- 
 tuf ;" by Dr Hutchesou of Glasgow. Ac- 
 cording to this very ingenious writer, the 
 moment of public good produced by an indi- 
 vidual, depending partly on his bf:iierolenre, 
 and partly on his ainti y, the relation between 
 these different moral ideas may be expressed 
 in the technical form of algebraists, by say- 
 ing that the first is in the compound pro- 
 portion of the two others. Hence, Dr 
 Hutcheson infers, that " the benmoirire ot 
 an agent (which in this system is synony- 
 mous with his moral merit) is proportional 
 to a fraction, having the moment of good 
 for the numerator, and the ability of the 
 agent for the denominator." Various other 
 examples of a similar nature occur in the 
 same work ; and are stated with a gravity 
 not altogether worthy of the author. It is 
 probable that they were intended merely as 
 illustr/itions of his general reasonings, not as 
 media of investigation for the discovery of 
 new conclusions ; but they appeared to Dr 
 Reid to be an innovation which it was of 
 importance to resist, on account of the ten- 
 dency it might have (by confounding the 
 evidence of different branches of science) to 
 retard the progress of knowledge. The very 
 high reputation which Dr Hutcheson then 
 possessed in the universities of Scotland, 
 added to the recent attempts of Pitcairn and 
 Cheyne to apply mathematical reasoning to 
 medicine, would bestow, it is likely, an in- 
 terest on Dr Reid's Essay at the time of 
 its publication, which it can scarcely be 
 expected to possess at present. Many of 
 the observations, however, which it contains, 
 are acute and original ; and all of them are 
 expressed with that clearness and precision 
 so conspicuous in his subsequent composi- 
 tions. The circumstance which renders a 
 subject susceptible of mathematical consider- 
 ation, is accurately stated ; and the proper 
 province of that science defined in such a 
 manner as sufficiently to expose the absur- 
 dity of those abuses of its technical phrase- 
 ology which were at that time prevalent. 
 From some passages in it, there is, I think, 
 ground for concluding that the author's 
 reading had not been very extensive pre- 
 vious to this period. The enumeration, in 
 particular, which he has given of the differ- 
 ent kinds of proper quandty, affords a proof 
 that he was not acquainted with the re- 
 fined yet sound disquisitions concerning the 
 nature of number and of proportion, which 
 had appeared, almost a century before, in 
 the " Aj athematical Lectures" of Dr Bar- 
 
 row ; nor with the remarks on the same 
 subject introduced by Dr Clarke in one of 
 his controversial letters addressed to 
 Leibnitz. 
 
 In the same paper, Dr Reid takes occa- 
 sion to offer some reflections on the dispute 
 between the Newtonians and Leibnitzians, 
 concerning the measure of forces. The 
 fundamental idea on which these reflections 
 proceed, is just and important ; and it 
 leads to the correction of an error com- 
 mitted very generally by the partisans of 
 both opinions— that of mistaking a question 
 concerning the comparative advantages of 
 two ({"Jiiiitions for a difterence of statement 
 with respect to a physical fact. It must. I 
 t'.iink, be acknowledged, at the same time, 
 that the whole merits of the controversy 
 are not here exhausted ; and that the hon- 
 our of placing this very subtle and abstruse 
 question in a point of view calculated to 
 reconcile completely the contending parties, 
 was reserved for M. D'Alembert. To have 
 fallen short of the success which attended 
 the inquiries of that eminent man, on a 
 subject so congenial to his favourite habits 
 of study, will not reflect any discredit on the 
 powers of Dr Reid's mind, in the judgment 
 of those who are at all acquainted with the 
 history of this celebrated discussion. 
 
 In 1752, the professors of King's Col- 
 lege elected Dr Reid Professor of Philoso- 
 phy, in testimony of the high opinion they 
 had formed of his learning and abilities. 
 Of the particular plan which he followed 
 in his academical lectures, while he held 
 this office, I have not been able to obtain 
 any satisfactory account; but the depart- 
 ment of science which was assigned to him 
 by the general system of education in that 
 university, was abundantly extensive ; com- 
 prehending Mathematics and Physics as 
 well as Logic and Ethics. A similar system 
 was pursued formerly in the other univer- 
 sities of Scotland ; the same professor then 
 conducting his pupil through all those 
 branches of knowledge which are now ap- 
 propriated to different teachers. And where 
 he happened fortunately to possess those 
 various accomplishments which distin- 
 guished Dr Reid in so remarkable a degree, 
 it cannot be doubted that the unity and 
 comprehensiveness of method of which such 
 academical courses admitted, must neces- 
 sarily have possessed important advantages 
 over that more minute subdivision of liter- 
 ary labour which has since been introduced. 
 But, as public establishments ought to adapt 
 themselves to what is ordinary, rather than 
 to what is possible, it is not surprising that 
 experience should have gradually suggested 
 an arrangement more suitable to the narrow 
 limits which commonly circumscribe human 
 genius. 
 
 Soon after Dr Reid's removal to Aber
 
 OF THOMAS REID, D.D. 
 
 deen, he projected (in conjunction with his 
 friend Dr John Gregory) a literary society, 
 which subsisted for many years, and which 
 seems to have had the happiest effects in 
 awakening and directing that spirit of pliilo- 
 sophical research which has since reflected 
 so much lustre on the north of Scotland. 
 The meetings of this society were held 
 weekly ; and afforded the members (beside 
 the advantages to be derived from a mutual 
 communication of their sentiments on the 
 common objects of their pursuit) an oppor- 
 tunity of subjecting their intended publica- 
 tions to the test of friendly criticism. The 
 number of valuable works which issued, 
 nearly about the same time, from individuals 
 connected with this institution — more par- 
 ticularly the writings of Reid, Gregory, 
 Campbell, Beattie, and Gerard — furnish the 
 best panegyric on the enlightened views of 
 those under whose direction it was origmally 
 formed. 
 
 Among these works, the most original 
 and profound was unquestionably the " In- 
 quiry into the Human iNIind," published by 
 Dr Reid in 1764. The plan appears to have 
 been conceived, and the subject deeply medi- 
 tated, by the author long before ; but it is 
 doubtful whether his modesty would have 
 ever permitted him to present to the world 
 the fruits of his solitary studies, without the 
 encouragement which he received from the 
 general acquiescence of his associates in the 
 most important conclusions to which he had 
 been led. 
 
 From a passage in the dedication, it would 
 seem that the speculations which termi- 
 nated in these conclusions, had commenced 
 as early as the year 1739 ; at which period 
 the publication of Mr Hume's " Treatise of 
 Human Nature," induced him, for the first 
 time, (as he himself informs us,) " to call 
 in question the ])rinci])les commonly received 
 with regard to the human understanding." 
 In his " Essays on the Intellectual Powers," 
 he acknowledges that, in his youth, he had, 
 without examination, admitted the esta- 
 blished opinions on which Mr Hume's sys- 
 tem of scepticism was raised ; and that it 
 was the consequences which these opinions 
 seemed to involve, which roused his suspi- 
 cions concerning their truth. " If I may 
 presume," says he, " to speak my own sen- 
 timents, I once believed the doctrine of Ideas 
 80 firmly as to embrace the whole of Berke- 
 ley's system along with it ; till, finding other 
 consequences to follow from it, which gave 
 me more uneasiness than thf want of a ma- 
 terial world, it came into my mind, more 
 than forty years ago, to put the question. 
 What evidence have I for this doctrine, that 
 all the objects of my knowledge are ideas in 
 my own mind ? I""roiii that time to the pre- 
 Bent, 1 have been candidly and impartiy,all 
 a« I think, seeking for the evidence of this 
 
 principle ; but can find none, excepting the 
 authority of philosophers." 
 
 In following the train of Dr Reid's re- 
 searches, this last extract merits attention, 
 as it contains an explicit avowal, on his 
 own part, that, at one period of his life, he 
 had been led, by Berkeley's reasonings, to 
 abandon the belief of the existence of matter. 
 The avowal does honour to his candour, 
 and the fact reflects no discredit on his saga- 
 city. The truth is, that this article of the 
 Berkleian system, however contrary to the 
 conclusions of a sounder philosophy, was 
 the error of no common mind. Considered 
 in contrast with that theory of materialism 
 which the excellent author was anxious to 
 supplant, it possessed important advantages, 
 not only in its tendency, but in its scientific 
 consistency ; and it afforded a proof, wher- 
 ever it met with a favourable reception, of 
 an understanding superior to those casual 
 associations which, in the apprehensions of 
 most men, blend indissolubly the pheno- 
 mena of thought with the objects of external 
 perception. It is recorded as a saying of 
 M. Turgot, (whose philosophical opinions in 
 some important points approached very 
 nearly to those of Dr Reid,*) that " he 
 who had never doubted of the existence of 
 matter, might be assured he had no turn for 
 metaphysical disquisitions. '' 
 
 As the refutation of Mr Hume's sceptical 
 theory was the great and professed object of 
 Dr Reid's " Inquiry," he was anxious, before 
 taking the field as a controversial writer, to 
 guard against the danger of misapprehend- 
 ing or misrepresenting the meaning of liis 
 adversary, by submitting his reasonings to 
 Mr Hume's private examination. With 
 this view, he availed himself of the good 
 offices of Dr Blair, with whom both he and 
 Mr Hume had long lived in habits of friend- 
 ship. The communications which he at 
 first transmitted, consisted only of detached 
 parts of the work ; and appear evidently, 
 from a correspondence which I have per- 
 used, to have conveyed a very imperfect 
 idea of his general system. In one of Mr 
 Hume's letters to Dr Blair, he betrays some 
 want of his usual good humour, in looking 
 forward to his new antagonist. " I wish," 
 says he, " that the parsons would confine 
 themselves to their old occupation of worry- 
 ing one another, and leave philosophers to 
 argue with tenii)er, moderation, and good 
 manners." After Mr Hume, however, had 
 read the manuscript, he addressed liimself 
 directly to the Author, in terms so candid 
 and liberal, that it woidd be unjust to his 
 memory to withhold from the public so 
 pleasing a memorial of his character : — 
 " By Dr Blair's means I have been 
 
 * Sec, In parlinilnr, the article *' Kxlitcnce" In 
 the " Encyclopeitie."
 
 ACCOUNT OF THE LIFE AND WRITINGS 
 
 favoured with the perusal of your perform- 
 ance, which I liavc read with great pleasure 
 and attention. It is cert<uiily very rare 
 that a piece so deeply pliilosophical is wrote 
 with so much spirit, and affords so much 
 entertainment to the reader ; though I must 
 still regret the disadvantages under which I 
 read it, as I never had the whole perform- 
 ance at once before me, and could not be 
 dble fully to compare one part with another. 
 To this reason, chiefly, I ascribe some 
 obscurities, which, in spite of your short 
 analysis or abstract, still seem to hang over 
 your system ; for I must do you the jus- 
 tice to own that, when I enter into your 
 ideas, no man appears to express hunself 
 with greater perspicuity than you do — a 
 talent which, above all others, is requisite 
 in that species of literature which you have 
 cultivated. There are some objections 
 which I would willingly propose to the chap- 
 ter, ' Of Sight,' did I not suspect that they 
 proceed from my not sufficiently under- 
 standing it ; and I am the more confirmed 
 in this suspicion, as Dr Blair tells me that 
 the former objections I made had been 
 derived chiefly from that cause. I shall, 
 tlierefore, forbear till the whole can be 
 before me, and shall not at present propose 
 any farther difficulties to your reasonings. 
 I shall only say that, if you have been able 
 to clear up these abstruse and important 
 subjects, instead of being mortified, I shall 
 be so vain as to pretend to a share of the 
 praise ; and shall think that my errors, by 
 having at least some coherence, had led you 
 to make a more strict review of my prin- 
 ciples, which were the common ones, and to 
 perceive their futility. 
 
 " As I was desirous to be of some use to 
 you, I kept a watchful eye all along over 
 your style ; but it is really so correct, and 
 so good English, that I found not anything 
 worth the remarking. There is only one 
 passage in this chapter, where you make 
 use of the phrase hin Itr to do, instead of 
 hinder fiom doing, wliich is the English 
 one ; but I could not find the passage when 
 I souglit for it. You may judge how un- 
 exceptionable the whole appeared to me, 
 when I could remark so small a blemish. 
 I beg my compliments to my friendly adver- 
 saries, Dr Campbell and Dr Gerard ; and 
 also to Dr Gregory, whom I suspect to be 
 of the same disposition, though he has not 
 openly declared himself such." 
 
 Of the particular doctrines contained in 
 Dr Reid's " Inquiry,'' I do not think it 
 necessary here to attempt any abstract ; 
 nor, indeed, do his speculations (conducted, 
 as they were, in strict conformity to the 
 rules of inductive philosophizing) afford a 
 subject for the same species of rapid out- 
 line which is so useful in facilitating the 
 study of a merely hypothetical theory. 
 
 Their great object was to record and to 
 cliissify the phenomena which the operations 
 of the human mind present to those who 
 reflect carefully on the subjects of their 
 consciousness ; and of such a history, it is 
 manifest that no abridgement could be 
 offered with advantage. Some reflections 
 on the peculiar plan adopted by the author, 
 and on the general scope of his researches 
 in this department of science, will after- 
 wards find a more convenient place, when I 
 shall have finished my account of his subse- 
 quent publications. 
 
 The idea of prosecuting the study of the 
 human mind, on a plan analagous to that 
 which had been so successfully adopted in 
 physics by the followers of Lord Bacon, if 
 not first conceived by Dr Reid, was, at least, 
 first carried successfully into execution in 
 his writings. An attempt had, long before, 
 been announced by Mr Hume, in the title- 
 page of his " Treatise of Human Nature,'' 
 to introduce the experimental method of 
 reasoning into moral subjects ; and some 
 admirable remarks are made in the intro- 
 duction to that work, on the errors into 
 which his predecessors had been betrayed 
 by the spirit of hypothesis ; and yet it is 
 now very generally admitted, that the whole 
 of his own system rests on a principle for 
 which there is no evidence but the authority 
 of philosophers ; and it is certain that, in 
 no part of it has he aimed to investigate, by 
 a systematical analysis, those general prin- 
 ciples of our constitution which can alone 
 afford a synthetical explanation of its com- 
 plicated phenomena. 
 
 I have often been disposed to think that Mr 
 Hume's inattention to those rules of philoso- 
 phizing which it was his professed intention 
 to exemplify, was owing, in part, to some 
 indistinctness in his notions concerning their 
 import. It does not appear that, in the 
 earlier part of his studies, he had paid much 
 attention to the models of investigation ex- 
 Iiibited in the writings of Newton and of 
 his successors ; and that he was by no 
 means aware of the extraordinary merits of 
 Bacon as a philosopher, nor of the influence 
 which his writings have had on the subse- 
 quent progress of physical discovery, is 
 demonstrated by the cold and qualified 
 encomium which is bestowed on his genius 
 in one of the most elaborate passages of 
 the " History of England." 
 
 In these respects, Dr Reid possessed 
 important advantages ; familiarized, from 
 his early years, to those experimental 
 inquiries which, in the course of the two 
 last centuries, have exalted natural philo- 
 sophy to the dignity of a science, and 
 determined strongly, by the peculiar bent 
 of his genius, to connect every step in the 
 progress of discovery with the history of the 
 liuman mind. Tlie influence of the general
 
 OF THOMAS REID, D. D, 
 
 views opened in the " XoNTim Organon" 
 may be traced in almost every page of his 
 writings ; and, indeed, the circumstance by 
 which tliese are so strongly and character- 
 istically distinguished, is, that they exhiliit 
 the first systematical attempt to exempliiy, 
 in the study of human nature, the same 
 plan of investigation which conducted 
 Newton to the properties of light, and to 
 the law of gravitation. It is from a steady 
 adherence to this plan, and not from the 
 superiority of his inventive powers, that he 
 claims to himself any merit as a philosopher ; 
 and he seems even willing (with a modesty 
 approaching to a fault) to abandon the 
 praise of what is commonly called fiennis, 
 to the authors of the systems which he was 
 anxious to refute. "It is genius," he ob- 
 serves in one passage, " and not the want 
 of it, that adulterates philosophy, and fills 
 it with error and false theory. A creative 
 imagination disdains the mean offices of 
 digging for a foundation, of removing rub- 
 bish, and carrying materials : leaving these 
 servile emploj'ments to the drudges in 
 science, it plans a design, and raises a fa- 
 bric. Invention supplies materials wliere 
 they are wanting, and fancy adds colouring 
 and every befitting ornament. The work 
 pleases the eye, and wants nothing but 
 solidity and a good foundation. It seems 
 even to vie with the works of nature, till 
 some succeeding architect blows it into 
 ruins, and builds as goodly a fabric of his 
 own in its place." 
 
 " Success in an inquiry of this kind," he 
 observes farther, " it is not in human power 
 to command ; but perluips it is possible, by 
 caution and humility, to avoid error and 
 delusion. The labyrinth may be too intri- 
 cate, and the thread too fine, to be traced 
 through all its windings ; but, if we stop 
 where we can trace it no farther, and secure 
 the ground we have gained, there is no harm 
 ilone; a quicker eye may in time trace it 
 farther." 
 
 The unassuming language with which 
 Dr Reid endeavours to remove the preju- 
 dices naturally excited by a new attempt to 
 philosophize on so unpromising, and hitherto 
 so ungrateful a subject, recalls to our recol- 
 lection those passages in which Lord Bacon 
 — filled as his own imagination was with tho 
 future grandeur of the fabric founded by 
 his hand — bespeaks the indulgence of his 
 readers, for an enter])rise ajiparently so 
 hopeless and presumptuous. The apology 
 he offers for himself, when compared witli 
 the height to which the structure of physical 
 knowledge hits since attained, may j)erha|is 
 liave some effect in attracting a more gene- 
 ral attention to pursuits still more im- 
 mediately interesting to njankind; and, at 
 any rat^-, it forms the best Cduunent on tlie 
 prophetic suggestions in wliich Dv Keid 
 
 occasionally indulges himself concerning the 
 future progress of moral speculation : — 
 
 " Si homines per tanta annorum spatia 
 viam verani inveniendi et colendi scientias 
 tenuissent, nee tamen ulterius progredi po- 
 tuissent, audax procul dubio et temeravia 
 foret opinio, posse rem in ulterius provehi. 
 Quod si in via ipsa erratum sit, atque homi- 
 num opera in iisconsumpta inquibusminime 
 oportebat, sequitur ex eo, uon in rebus 
 ipsis difficultatem oriri, quse potestatis nos- 
 trEenonsuut; sed inintellectu humano,ejus- 
 que usu et applicatione, quae res remedium 
 et mediciuam suscipit."* — " De nobis ipsis 
 silemus : de re autem qnie agitur, petimus ; 
 Ut homines earn non ojnnioneni, sed opus 
 esse cogitent ; ac pro certo habeant, non 
 sectse nos alicujus, aut placiti, sed ntilitatis 
 et amplitudinis humauaj fundamenta moliri. 
 Prseterea, ut bene sperent ; neque Instau- 
 rationem nostram ut quiddam infinitum et 
 ultra mortale fingant, et animo concipiant ; 
 quura revera sit infinitl erroris finis et ter- 
 minus legitimus."i- 
 
 The impression produced on the minds of 
 speculative men, by the publication of Dr 
 Reid's " Inquiry," wasfully asgreatas could 
 be expected from the nature of his under- 
 taking. It was a work neither addressed 
 to the multitude, nor level to their compre- 
 hension ; iind the freedom with which it 
 canvassed opinions sanctioned by the highest 
 authorities, was ill calculated to conciliate 
 the favour of the learned. A few, however, 
 habituated, like the author, to the analytical 
 researches of the Newtonian school, soon 
 perceived the extent of his views, and re- 
 cognised in his pages the genuine spirit and 
 language of inductive investigation. Among 
 the members of this University, ]Mr Fergu- 
 son was the first to ap])laud Dr Reid's 
 success ; warmly recommending to his pu- 
 pils a steady prosecution of the same plan, 
 as the only eH'ectual method of asceitaining 
 the general ps inciples of the human frame ; 
 and illustrating, happily, by his own pro- 
 found and eloquent disquisitions, the appli- 
 cation of such studios to the conduct of the 
 understanding and to the great concerns of 
 life. I recollect, too, wlien I attended (about 
 the year 1771) the lectures of the late Mr 
 Russell, to have heard high encomiums on 
 the philosophy of Reid, in the course of 
 those compreh.ensive discussions concerning 
 the objects and tlie rules of experimental 
 science, with which he so agreeably diversi- 
 fic(l tiie particular doctrines of physics. Nor 
 must I omit this opjiort unity of paying a 
 tribute to the memory of my old friend, Mr 
 Stevenson, then Professor of Logic ; whose 
 candid mind, at tlie age of seventy, gave a 
 welcome reception to a system subversive 
 of the theories which lie had tfiught for 
 
 ♦ Nov. f )r(?. «1. t IintBur. Mag— I'liefnt.
 
 10 
 
 ACCOUNT OF THE LIFE AND WRITINGS 
 
 forty years ; and whose zeal for the ad- 
 vancement of knowledtje prompted him, 
 when his career was almost finished, to 
 undertake the laborious task of new-model- 
 ling that useful compilation of elementary 
 instruction to which a singular diffidence 
 of his own powers limited his literary exer- 
 tions. 
 
 It is with no common feelings of respect 
 and of gratitude, that I now recall the names 
 of those to whom I owe my first attach- 
 ment to these studies, and the happiness 
 of a liberal occupation superior to the more 
 aspiring aims of a servile ambition. 
 
 From the University of CJiasgow, Dr 
 Reid's " Inquiry" received a still more 
 substantial testimony of approbation ; tne 
 author having been invited, in 17<)3, by 
 that learned body, to the Professorship of 
 Moral Philosophy, then vacant by the 
 resignation of Mr Smith. The prefei-nient 
 was, in many respects, advantageous ; 
 affording an income considerably greater 
 than he enjoyed at Aberdeen ; and enabling 
 him to concentrate to his favourite objects, 
 that attention which had been hitherto dis- 
 tracted by the miscellaneous nature of his 
 academical engagements. It was not, how- 
 ever, without reluctance, that he consented 
 to tear himself from a spot where he had 
 so long been fastening his roots ; and, 
 much as he loved the society in which he 
 passed the remainder of his days, I am 
 doubtful if, in his mind, it compensated the 
 sacrifice of earlier habits and connections. 
 
 Abstracting from the charm of local 
 attachment, the University of Gla.sgow, at 
 the time when Dr lieid was adopted as one 
 of its members, presented strong attrac- 
 tions to reconcile him to his change of 
 situation. Robert Sinison, the great re- 
 storer of ancient geometry, was still alive ; 
 and, although far advanced in years, pre- 
 served unimpaired his ardour in study, his 
 relish for social relaxation, and his amusing 
 singularities of humour. Dr Moor com- 
 bined, with a gaiety and a levity foreign to 
 this climate, the profound attainments of a 
 scholar and of a mathematician. In Dr 
 Black, to whose fortunate genius a new 
 world of science had just opened, Reid 
 acknowledged an instructor and a guide ; 
 and met a simplicity of manners congenial 
 to liisown. Thf^ Wilsons (both father and 
 son) were forn;o!i to attach his heart by tlie 
 similarity of their scientific pursuits, and 
 an eutire sympathy with his views and sen- 
 timents. Nor was he less delighted with 
 the good-humoured opposition whieh his 
 opinions never failed to encounter in the 
 acuteness of ^lillar — then in the vigour of 
 youthful genius, and warm from the lessons 
 of a different school. Dr Leechman, the 
 friend and biographer of Hutcheson, was 
 the ofificLal head of the College ; and added 
 
 the weight of a venerable name to the repu- 
 tation of a community which he had once 
 adorned in a more active station.* 
 
 Animated by the zeal of such associates, 
 and by the busy scenes which his new resi- 
 dence presented in every department of 
 useful industry, Dr Reid entered on his 
 functions at Glasgow with an ardour not 
 common at the period of life which he had 
 now attained. His researches concerning 
 the human mind, and the principles of 
 morals, which had occupied but an incon- 
 siderable space in the wide circle of science 
 allotted to him by his former office, were 
 extended and methodized in a course which 
 employed five hours every week, during six 
 months of the year ; the example of his 
 illustrious predecessor, and the prevailing 
 topics of conversation around him, occa- 
 sionally turned his thoughts to commercial 
 politics, and produced some ingenious essays 
 on different questions connected with trade, 
 which were communicated to a private 
 society of his academical friends ; his early 
 passion for the mathematical sciences was 
 revived by the conveisation of Simson, 
 !Moor, and the Wilsons ; and, at the age of 
 fifty-five, he attended the lectures of Black, 
 with a juvenile curiosity and enthusiasm. 
 
 As the substance of Dr Reid's lectures at 
 Glasgow (at least of that part of them 
 which was most important and original) 
 has been since given to the public in a more 
 improved form, it is unnecessary for me to 
 eular^^e on the plan which he followed in 
 the discharge of his official duties. I shall 
 therefore only observe, that, beside his spe- 
 culations on the intellectual and active 
 powers of man, and a system of practi- 
 cal ethics, his course comprehended some 
 geneiral views with respect to natural juris- 
 prudence, and the fundamental principles of 
 politics. A few lectures on rhetoric, which 
 were read, at a separate hour, to a more 
 advanced class of students, formed a volun- 
 tary addition to the appropriate functions 
 of his office, to which it is probable he 
 was prompted, rather by a wish to supply 
 what was then a deficiency in the established 
 course of education, than by any predilec- 
 tion for a branch of study so foreign to his 
 ordinary pursuits. 
 
 The merits of DrReid as a public teacher 
 vv'ere derived chiefly from that rich fund of 
 original and instructive philosophy which is 
 to be found in his writings, and from his 
 unwearied assiduity in inculcating principles 
 which he conceived to be of essential import- 
 ance to human happiness. In his eiocution 
 and mode of instruction, there was nothing 
 peculiarly attractive. He seldom, if ever, 
 indulged himself in the warmth of extem- 
 pore discourse ; nor was his manner of 
 
 * Note C.
 
 OF THOMAS IlEID, D.D. 
 
 11 
 
 reading: calculated to increase the effect of 
 what he had committed to writinc;. Such, 
 however, was the simplicity and perspicuity 
 of his style, such the gravity and authority 
 of his character, and such the general in- 
 terest of his young hearers in the doctrines 
 which he taught, that, by the numerous 
 audiences to wliich his instructions were 
 addressed, he was heard uniformly with the 
 most silent and respectful attention. On 
 this subject, I speak from personal know- 
 ledge ; having had the good fortune, during 
 a considerable part of winter 177-j to be 
 one of his pupils. 
 
 It does not appear to me, from what I 
 am now able to recollect of the order which 
 he observed in treating the different parts 
 of his subject, that he had laid much stress 
 on systematical arrangement. It is pro- 
 bable that he availed himself of whatever 
 materials his private inquiries attbrded, for 
 his academical compositions, without aiming 
 at the merit of combining them into a whole, 
 by a comprehensive and regular design — an 
 undertaking to which, if I am not mistaken, 
 the established forms of his university, 
 consecrated by long custom, would have 
 presented some obstacles. One thing is 
 certain, that neither he nor his immediate 
 predecessor ever published any general pro- 
 spectus of their respective plans, nor any 
 heads or otitlincs to assist their students in 
 tracing the trains of thought which suggested 
 their vaiious transitions. 
 
 The interest, iiowever, excited by such 
 details as these, even if it were in my power 
 to render them more full and satisfactory, 
 must necessarily be temporary and local ; 
 and I, therefore, hasten to observations of 
 a more general nature, on the distinguishing 
 characteristics of Dr Reid's philosophical 
 genius, and on the spirit and scope of those 
 researches which he has berjueathed to 
 posterity concerning the phenomena and 
 laws of the human mind. In mentioning 
 his first performance on this subject, I have 
 already anticipated a few remarks which 
 are e<iua!ly applii'able to his subsequent 
 publications ; but the hints tlien suggested 
 were too slight to ])lace in so strong a 
 light as I C( uld wish the peculiarities of 
 that mode of investigation which it was the 
 great object of bis writings to recommend 
 and to exemplify. His own anxiety to 
 neglect notliiiig that might contriliuto to its 
 farther illustration induced him, while his 
 health and faculties were yet entire, to 
 withdraw fnjm his jjublic labours, and to 
 devote himself, with an undivided attention, 
 to a task of more extensive and permanent 
 utility. It was in tiie year 17<ll that he 
 carried tliis design into execution, at a 
 period of life (for he was then upwards of 
 Bcvcnty) when the infirmities of age might 
 be supposed to account sufficiently for his 
 
 retreat ; but when, in fact, neither the 
 vigour of his mind nor of his body seemed 
 to have suffered any injury from time. The 
 works which he published not many years 
 afterwards, afford a sufficient proof of the 
 assiduity with which he liad availed hunself 
 of his literary leisure — his " Essays on th» 
 Intellectual Powers of Man" appearing in 
 1785, and those on the " Active Powers" 
 in 1788. 
 
 As these two performances are, both of 
 them, parts of one great w ork, to which his 
 " Inquiry into the Human Mind" may be 
 regarded as the introduction, I have re- 
 served for this place whatever critical refieL-- 
 tions I have to offer on his merits as an 
 author; conceiving that they would be more 
 likely to produce their intended effect, when 
 presented at once in a connected form, than 
 if interspersed, according to a chronological 
 order, with the details of a biographical 
 narrative. 
 
 SECTION II. 
 
 OBSERVATIONS ON THE SPIRIT AND SCOPK OP 
 BR reid's philosophy. 
 
 I iiA\'E already observed that the dis- 
 tinguisliiugfeatureof Dr Reid's philosophy, 
 is the systematical steadiness with which 
 he has adhered in his inquiries, to that plan 
 of investigation which is delineated m the 
 " Novum Organon," and which has been so 
 happily exemplified in physics by Sir Isaac 
 Newton and his followers. To recommend 
 this plan as the only efi'ectual method of 
 enlarging our knowledge of nature, was the 
 favourite aim of all his studies, and a topic 
 on which he thought he could not enlarge 
 too much, in conversing or corresponding 
 with his younger friends. In a letter to D/ 
 Gregory, which I have perused, he particu- 
 larly congratulates him upon his accjuaint- 
 anee with Lord Bacon's works ; adding, 
 " I am very apt to measure a man's under- 
 standing by the opinion he entertains of 
 that author." 
 
 It were perhaps to be wished that he had 
 taken a little more pains to illustrate the 
 fundamental rules of that logic the value 
 of which he estimated so highly ; more 
 especially, to point out the modifications 
 with which it is applicable to the science of 
 mind. Many important hints, indeed, con- 
 nected with tills subject, m.ay be collected 
 from different parts of his writings ; but I 
 am inclined to think tiiat a more ample 
 discussi(jnof it, in a preliminary dissertation, 
 might have thrown light on the scope of 
 many of his reBearclies, and obviated sonio 
 of the most plausible objections which have 
 been stated to his conclusions.
 
 12 
 
 ACCOUNT OF THE LIFE AND WRITINGS 
 
 It is not, however, ray intention at pre- 
 sent to attempt to supply a deshlrralum of 
 60 great a magnitude — au undertaking 
 which, I trust, will find a more convenient 
 place, in the farther prosecution of those 
 speculations with respect to the intellectual 
 powers which I have already submitted to 
 the public. The detached remarks which 
 follow, are offered merely as a supplement 
 to what I have stated concerning the nature 
 and object of this branch of study, in the 
 Introduction to the " Philosophy of the 
 Human Mind." 
 
 The infiuence of Bacon's genius on the 
 subsequent progress of ])hysical discovery, 
 has been seldom fairly appreciated — by some 
 writers almost entirely overlooked, and by 
 others considered as the sole cause of the 
 reformation in science which has since taken 
 place. Of these two extremes, the latter 
 certainly is the least wide of the truth ; for, 
 in the whole history of letters, no other 
 individual can be mentioned, whose exer- 
 tions have had so indisputable an effect in 
 forwarding the intellectual progress of man- 
 kind. On the other hand, it must be ac- 
 knowledged, that, before the era when Bacon 
 appeared, various philosophers in different 
 parts of Europe had struck into the right 
 path ; and it may perhaps be doubted 
 whether any one important rule with respect 
 to the true method of investigation be con- 
 tained in his works, of which no hint can 
 be traced in those of his predecessors. His 
 great merit lay in concentrating their feeble 
 and scattered lights ; fixing the attention 
 of philosophers on the distinguishing cha- 
 racteristics of true and of false science, by 
 a fehcity of illustration peculiar to himself, 
 seconded by the commanding powers of a 
 bold and figurative eloquence. The method 
 of investigation which he recommended had 
 been previously followed in every instance 
 in which any solid discovery had been made 
 with respect to the laws of nature ; but it 
 had been followed accidentally and without 
 any regular, preconceived design ; and it 
 was reserved for him to reduce to rule and 
 method what others had effected, either 
 fortuitously, or from some momentary 
 glimpse of the truth. It is justly observed 
 by Dr Reid, that " the man who first dis- 
 covered that cold freezes water, and that 
 heat turns it into vapour, proceeded on the 
 same general principle by which Newton 
 discovered the law of gravitation and the 
 properties of light. His ' Regulte Philo- 
 sophandi' are maxims of commonsense, and 
 are practised every day in common life ; 
 and he who philosophizes by other rules, 
 either concerning the material system or 
 concerning the mind, mistakes his aim." 
 
 These remarks are not intended to detract 
 from the just glory of Bacon ; for tiiey 
 apply to all those, without exception, who 
 
 have systematized the principles of any of 
 the arts. Indeed, they apply less forcibly 
 to him than to any other philosopher whose 
 studies have been directed to objects analo- 
 gous to his ; inasmuch as we know of no 
 art of which the rules have been reduced 
 successfully into a didactic form, when the 
 art itself was as much in infancy as expe- 
 rimental philosophy was when Bacon wrote. 
 Nor must it be supposed that the utility 
 was small of thus attempting to systematize 
 the accidental processes of unenlightened 
 ingenuity, and to give to the noblest exer- 
 tions of human reason, the same advan- 
 tages of scientific method which have 
 contributed so much to insure the success 
 of genius in pursuits of inferior importance. 
 The very philosophical motto which Rey- 
 nolds has so happily prefixed to his 
 " Academical Discourses," admits, on this 
 occasion, of a still more appropriate appli- 
 cation : — " Omnia fere quse praeceptis con- 
 tinentur ab ingeniosis hominibus fiunt ; sed 
 casu quodam magis quam scientia. Ideoque 
 doctrina et animadversio adhibenda est, ut 
 ea quae interdum sine ratione nobis occur- 
 runt, semper in nostra protestate sint ; et 
 quoties res postulaverit, a nobis ex prsepa- 
 rato adhibeantur." 
 
 But, although a few superior minds seem 
 to have been, in some measure, predisposed 
 for that revolution in science which Bacon 
 contributed so powerfully to accomplish, 
 the case was very different with the great 
 majority of those who were then most dis- 
 tinguished for learning and talents. His 
 views were plainly too advanced for the age 
 in which he lived ; and, that he was sen- 
 sible of this himself, appears from those 
 remarkable passages in which lie styles 
 himself " the servant of posterity," and 
 " bequeaths his fame to future times." 
 Hobbes, who, in his early youth, had 
 enjoyed his friendship, speaks, a consider- 
 able time after Bacon's death, of experi- 
 mental philosophy, in terms of contempt ; 
 influenced, probably, not a little by the 
 tendency he perceived in the inductive 
 method of inquiry, to undermine the found- 
 ations of that fabric of scepticism which it 
 was the great object of his labours to rear. 
 Nay, even during the course of the last 
 century, it has been less from Bacon's own 
 speculations, than from the examples of 
 sound investigation exhibited by a few emi- 
 nent men, who professed to follow him as 
 their guide, that the practical spirit of his 
 writings has been caught by the multitude 
 of physical experimentalists over Europe ; 
 truth and good sense descending gradu;illy, 
 in this as in other instances, by the force of 
 imitation and of early habit, from the 
 higher orders of intellect to the lower. In 
 some parts of the Continent, more espe- 
 cially, the circulation of Bacon's philoso-
 
 OF THOMAS REID, D.D. 
 
 13 
 
 pTiical works has been surprisim;!}' slow. 
 It is doubtful whether Des Cartes himself 
 ever perused them ;" and, as late as the 
 year lTo9, if we may credit IMontucla, they 
 were very little known in France. Tlie 
 introductory discourse prefixed by D'Alem- 
 bert to the " Encyclopedie," first recom- 
 mended them, in that country, to general 
 attention. 
 
 The change which has taken place, dur- 
 ing the two last centuries, in the plan of 
 physical research, and the success which 
 has so remarkably attended it, could not 
 fail to suggest an idea, that something 
 analogous might probably be accomplished 
 at a future period, with respect to the 
 phenomena of the intellectual world. And, 
 accordingly, various hints of this kind may 
 be traced in different authors, since the 
 era of Xewton's discoveries. A memorable 
 instance occurs in the prediction with which 
 that great man concludes his " Optics :" — 
 " That, if natural philosophy, in all its 
 parts, by pursuing the inductive method, 
 shall at length be perfected, the bounds of 
 moral philosophy will also be enlarged." 
 Similar remarks may be found in other 
 publications ; particularly in Mr Hume's 
 " Treatise of Human Nature," where the 
 subject is enlarged on with niucli ingenuity. 
 As far, however, as I am able to judge, Dr 
 Reid was the first who conceived justly and 
 clearly the analogy between these two dif- 
 ferent branches of human knowledge ; de- 
 fining, with precision, the distinct provinces 
 of observation and reflection, "I" in furnish- 
 ing the data of all our reasonings concerning 
 matter and mind ; and demonstrating the 
 necessity of a careful separation between the 
 phenomena which they respectively exhibit, 
 while we adhere to the same mode of philo- 
 sophizing in investigating the laws of buth. 
 That so many philosophers should have 
 thus missed their aim, in prosecuting the 
 study of the liuman mind, will appear the 
 less surprising when we consider in how 
 many difficulties, peculiar to ilself, this 
 
 • This is a mistake, whinh it is tlie more requisite 
 to correct, because Mr Stewart's authoiity in liistori- 
 Cal points is. in consequence «f liish ibi nal accuracy, 
 deservedly liifjh. It is repeated, if I recoiled aright, 
 in more articulate terms, m the" Disserlationon the 
 I'roKresS of Metaphysical I'hilosophy." Des Cartes, 
 in three or four passages ol his " Letters " makes 
 honouralile men ion of Hacoii ^nil his method ; his 
 works lie -eeins not only to have perused hut stuilieil 
 There 8, however, no reason to suppose that I)e> Car. 
 tet was acquaiiiied with the wrilincs of his great 
 predecessor in the early |iari of his life^ and hisovi n 
 views i.i philosophy were probably not allettCil by 
 • his influence. Mr Stewart, likewise, greatly under. 
 rates th" influence ot the Kaconian writings in pene. 
 ral. previous to the iecoti;mendatiori of D'Alein- 
 bert. On this subject, tlir reader is referred lo a 
 valuable paper by i'roh'ssdr N.ipier on the " Scope 
 an'J liiflueoceof the f'.aconian I'I'ilosophv," in the 
 Transactions of the Koyal Society of Kdinburgh.— H. 
 
 + See a note on Ueid's >ixlh " Essay on the Intel. 
 /ei'iual Powers," chap I.,atid ol Iheorieiual edition, 
 1>. iI7,— H 
 
 science is involved. It is sufficient at 
 present to mention those which arise from 
 the metaphorical origin of all the words 
 which express the intellectual phenomena ; 
 from the subtle and fugitive nature of the 
 objects of our reasonings; from the habits 
 of inattention we acquire, in early life, to the 
 subjects of our consciousness ; and from the 
 prejudices which early impressions and asso- 
 ciations create to warp our opinions. It 
 must be remembered, too, that, in the 
 science of mind, (so imperfectly are its logi- 
 cal rules as yet understood ! ) we have not 
 the same checks on the abuses of our rea- 
 soning powers which serve to guard us 
 against error in our other researches. In 
 physics, a speculative mistake is abandoned 
 when contradicted by facts which strike 
 the senses. In mathematics, an absurd or 
 inconsistent conclusion is admitted as a 
 demonstrative proof of a faulty hypothesis. 
 But, in those inquiries which relate to the 
 principles of human nature, the absurdities 
 and inconsistencies to which we are led by 
 almost all the systems hitherto proposed, 
 instead of suggesting corrections and im- 
 provements on these systems, have too 
 frequently had the efltect of producing 
 scepticism with respect to all of them alike. 
 How melancholy is the confession of 
 Hume ! — " The intense view of these 
 manifold contradictions and imperfections 
 in human reason, has so wrought upon me, 
 and heated my brain, that I am ready to 
 reject all belief and reasoning, and can 
 look upon no opinion even as more prob- 
 able or likely than another." 
 
 Under these discouragements to this 
 branch of study, it affords us some comfort 
 to reflect on the great number of important 
 facts with respect to the mind, which are 
 scattered in the writings of philosojihers. 
 As the subject of our inquiry here lies 
 within our own breast, a considerable mix- 
 ture of truth may be expected even in those 
 systems which are most erroneous ; not 
 only because a number of men can scarcely 
 be long imposed on by a hypothesis which 
 is perfectly groundless, concerning the ob- 
 jects of their own consciousness, but because 
 it is generally by an alliance with truth, 
 and with the original principles of human 
 nature, that prejudices and associations 
 produce their effects. Perhaps it may even 
 be affirmed, that our progress in this re- 
 search depends less on the degree of our 
 industry and invention, than on our saga- 
 city and good sense in scpaiating old dis- 
 coveries from the errors which have bet ii 
 blended with them ; and on th;it candid 
 and dispassionate temiier that miy i)revent 
 us from being led astray by th ■ love of 
 novelty, or the affectation of singulirity. 
 In this respect, (ho science of mind pos- 
 sesses a very important advantage over
 
 14 
 
 ACCOUNT OF THE LIFE AND VFRITINGS 
 
 that wliich relates to the laws of the mate- 
 rial world. The former has been culti- 
 vated with more or less success in all ages 
 and countries : the facts which serve as 
 the basis of the latter have, with a very few 
 exceptions, been collected during^the course 
 of the two last centuries. An observation 
 similar to this is applied to systems of 
 ethics by Mr Smith, in his account of the 
 theory of Mandeville ; and the illustration 
 he gives of it may be extended with equal 
 propriety to the science of mind in general : 
 — " A system of natural philosophy," he 
 remarks, " may appear very plausible, and 
 be, for a long time, very generally received 
 in the world, and yet liave no foundation in 
 nature, nor any sort of resemblance to the 
 truth. But it is otherwise with systems of 
 moral philosophy. When a traveller gives 
 an account of some distant country, he may 
 impose upon our credulity the most ground- 
 less and absurd fictions as the most certain 
 matters of fact ; but when a person pretends 
 to inform us of what passes in ourneighbour- 
 hood, and of the affairs of the very parish 
 we live in — though here, too, if we are so 
 careless as not to examine things with our 
 own eyes, he may deceive us in many re- 
 spects — yet the greatest falsehoods which 
 he imposes on us must bear some resem- 
 blance to the truth, and must even have a 
 considerable mixture of truth in them." 
 
 These considerations demonstrate the es- 
 sential importance, in this branch of study, 
 of forming, at the commencement of our 
 inquiries, just notions of the criteria of true 
 and false science, and of the rules of philoso- 
 phical investigation. They demonstrate, at 
 the same time, that an attention to the rules 
 of philosophizing, as they are exemplified in 
 thephysical researches of Newton and his fol- 
 lowers, although the best of all preparations 
 for an examination of the mental phenomena, 
 is but one of the steps necessary to insure 
 our success. On an accurate comparison of 
 the two subjects, it might probably appear, 
 that, after this preliminary step has been 
 gained, the most arduous part of the process 
 still remains. One thing is certain, that it 
 is not from any defect in the power of ratio- 
 cination or deduction, that our speculative 
 errors chiefly arise — a fact of which we 
 have a decisive proof in the facility with 
 which most students may be taught the 
 mathematical and physical sciences, when 
 compared with the difficulty of leading their 
 minds to the truth, on questions of morals 
 and politics. 
 
 The logical rules which lay the foundation 
 of sound and useful conclusions concerning 
 the laws of this internal world, although 
 not altogether overlooked by Lord Bacon, 
 were plainly not the principal object of his 
 work ; and what he has written on the sub- 
 ject,consists chiefly of detached hints dropped 
 
 casually in the course of other speculations. 
 A comprehensive view of the sciences and 
 arts dependent on the philosophy of the 
 human mind, exhibiting the relations which 
 they bear to each other, and to the general 
 system of human knowledge, would form a 
 natural and useful introduction to the study 
 of these logical principles ; but such a view 
 remains still a desideiutnm, after all the 
 advances made towards it by Bacon and 
 D'Alembert. Indeed, in the present im- 
 proved state of things, much is wanting to 
 complete and perfect that more simple part 
 of their intellectual map which relates to 
 the material universe. Of the inconsider- 
 able progress hitherto made towards a just 
 delineation of the method to be pursued in 
 studying the mental phenomena, no other 
 evidence is necessary than this, That the 
 sources of error and false judgment, so pe- 
 culiarly connected, in consequence of the 
 association of ideas, with studies in which 
 our best interests are immediately and deeply 
 concerned, have never yet been investigated 
 with such accuracy as to afford effectual 
 aid to the student, in his attempts to coun- 
 teract their influence. One of these sources 
 alone — that which arises from the imper- 
 fections of language — furnishes an exception 
 to the general remark. It attracted, fortu- 
 nately, the particular notice of Locke, whose 
 observations with respect to it, compose, 
 perhaps, the most valuable part of his philo- 
 sophical writings; and, since the time of 
 CondiUac, the subject has been still more 
 deeply analyzed by others. Even on this 
 article, much yet remains to be done ; but 
 enough has been already accomplished to 
 justify the proi'ound aphorism in which Bacon 
 pointed it out to the attention of his follow- 
 ers : — " Credunt homines rationem suam 
 verbis imperare ; sed fit etiam ut verba vim 
 suam super rationem retorqueant."* 
 
 Into these logical discussions concerning 
 the means of advancing the philosophy of 
 human nature, Dr Reid has seldom entered ; 
 and still more rarely has he indulged him- 
 self in tracing the numerous relations by 
 which this philosophy is connected with the 
 practical business of life. But he has done 
 what was still more essential at the time he 
 wrote : he has exemplified, with the happiest 
 success, that method of investigation by 
 which alone any solid progress can be made ; 
 directing his inquiries to a subject which 
 forms a necessary groundwork for the labours 
 of his successors — an analysis of the various 
 powers and principles belonging to our con- 
 stitution. Of the importance of this under- 
 taking, it is sufficient to observe, that it 
 
 * This passage of Bacon forms the motto loa very 
 ingenious and phil<i9o|)hical dissertation, (lately pub. 
 lished by M. Prcvosr ot Geneva,) entitled, " Des 
 Signes envisages relativement a leiir Influence sur la 
 Formation des lilacs." Paris, an 8.
 
 OF THOMAS REID, D.D. 
 
 J5 
 
 stands somewhat, although I confess not 
 altogether, in the same relation to the dif- 
 ferent branches of intellectual and moral 
 science, (such as granmiar, rhetoric, logic, 
 ethics, natural theology, and politics,) in 
 which the anatomy of the human body 
 stands to the different branches of physio- 
 logy and pathology. And, as a course of 
 medical education naturally, or rather ne- 
 cessarily, begins with a general survey of 
 man's animal frame, so I apprehend that 
 the proper, or rather the essential prepara- 
 tion for those studies which regard our 
 nobler concerns, is an examination of the 
 principles which belong to man as an intel- 
 ligent, active, social, and moral being. Nor 
 does the importance of such an analysis rest 
 here ; it exerts an influence over all those 
 sciences and arts which are connected with 
 the material world ; and the philosophy of 
 Bacon itself, while it points out the road to 
 physical truth, is but a branch of the philo- 
 sophy of the human mind. 
 
 The substance of these remarks is admir- 
 ably expressed by Mr Hume in the follow- 
 ing passage — allowances being made for a 
 few trifling peculiarities of expression, bor- 
 rowed from the theories which were pre- 
 valent at the time when he wrote : — " 'Tis 
 evident that all the sciences have a relation, 
 greater or less, to human nature; and that, 
 however wide any of them may seem to run 
 from it, they still return back by one pass- 
 age or another. Even mathematics, natural 
 philosophy, and natural religion, are in some 
 measure dependent on the science of man ; 
 since they lie under the cognizance of men, 
 and are judged of by their powers and facul- 
 ties. It is impossible to tell what changes 
 and improvements we might make in these 
 sciences, were we thoroughly acquainted 
 with the extent and force of human under- 
 standing, and could explain the nature of 
 the ideas we employ, and of the operations 
 we perform in our reasonings. 
 
 " If, therefore, the sciences of mathe- 
 matics, natural philosophy, and natural 
 religion, have such a dej)endenee on the 
 knowledge of man, what may be expected 
 in the other sciences, whose connection with 
 human nature is more close and intimate ? 
 The sole end of logic is to explaui the prin- 
 ciples and operations of our reasoning 
 faculty, and the nature of our ideas ; morals 
 and criticism regard our tastes and senti- 
 ments ; and politics consider men as united 
 in society and dependent on each other. In 
 these four sciences of logic, morals, criti- 
 ciam, and politics, is comprehended almost 
 everything which it can any way import us 
 to be acquainted with, or which c.-m tend 
 eitlier to the improvement or ornament of 
 the human mind. 
 
 " Here, then, is tlie only expedient from 
 which we can hope for success in our philo- 
 
 sophical researches : to leave the tedious, 
 lingering method, which we have hitherto 
 followed ; and, instead of taking, now and 
 then, a castle or village on the frontier, to 
 march up directly to the capital or centre 
 of these sciences — to human nature itself; 
 which being once masters of, we may every- 
 where else hope for an easy victory. From 
 this station, we may extend our conquests 
 overall those sciences which moreintimately 
 concern liuman life, and may afterwards 
 proceed at leisure to discover more fully 
 those which are the objects of pure curiosity. 
 There is no question of importance whose 
 decision is not comprised in the science of 
 man ; and there is none wliich can be de- 
 cided with any certainty before we become 
 acquainted with that science." 
 
 To prepare the way for the accomplish- 
 ment of the design so forcibly recommended 
 in the foregoing quotation — by exemplifying, 
 in an analysis of our most important intel- 
 lectual and active principles, the only method 
 of carrying it successfully into execution — 
 was the great oliject of Dr Reid m all his 
 various philosophical publications. In ex- 
 aminmg these principles, he had chiefly in 
 view a vindication of those fundamental laws 
 of belief which form the groundwork of 
 human knowledge, against the attacks made 
 on their authority in some modern systems 
 of scepticism ; lea\-ing to his successors the 
 more agreeable task of applying the philo- 
 sophy of the mind to its practical uses. On 
 the a/ia/i/sis and classification of our powers, 
 which he has proposed, much room for im- 
 provement must have been left in so vast 
 an undertaking ; but imperfections of this 
 kind do not necessarily affect the justness 
 of his conclusions, even where they may 
 suggest to future inquirers the advantages 
 of a simpler arrangement, and a more de- 
 finite phraseology. Nor must it be forgotten 
 that, in consequence of the plan he has fol- 
 lowed, the mistakes which may be detected 
 in particular parts of Ids works imply no 
 such weakness in the fabric he has reared 
 as might have been justly apprehended, had 
 he presented a connected system founded 
 on gratuitous hypothesis, or on arbitrary 
 definitions. The detections, on the con- 
 trary, of his occasional errors, may be ex- 
 pected, from the invariable consistency and 
 harmony of truth, to throw new lights on 
 those parts of his work where his inquiries 
 have been more successful ; as tlie correc- 
 tion of a particular mistatement in an 
 authentic history is often found, by com- 
 pleting an imperfect link, or reconciling a 
 seeming contradiction, to dispel the doubts 
 which jumg over the most faithful and 
 accurate details of the nnrrative. 
 
 In Dr Ileid's first performance, he con- 
 fined himself entirely to the five senses, and 
 the principles of our nature necessarily
 
 Ifi 
 
 ACCOUNT OF THE LIFE AND WRITINGS 
 
 connected with them ; reserving the further 
 prosecution of thosubject for a future period. 
 At that time, indeed, he seems to have 
 thought, that a more comprehensive exami- 
 nation of the mind was an enterprise too 
 great for one individual. " Tlie powers,'' 
 he observes, " of memory, of imagination, 
 of taste, of reasoning, of moral perception, 
 the will, the passions, the affections, and all 
 the active powers of the soul, present a 
 boundless field of philosophical disquisition, 
 which the author of this ' Inquiry' is far 
 from thinking himself able to explore with 
 accuracy. INIany authors of ingenuity, 
 ancient and modern, have made incursions 
 into this vast territory, and have commu- 
 nicated useful observations ; but there is 
 reason to believe that those who have pre- 
 tended to give us a map of the whole, have 
 satisfied themselves with a very inaccurate 
 and incomplete survey. If Galileo had 
 attempted a complete system of natural 
 philosophy, he had probably done little 
 service to mankind ; but, by confining him- 
 self to what was within his comprehension, 
 he laid the foundation of a system of know- 
 ledge, which rises by degrees, and does 
 honour to the human imderstanding. New- 
 ton, building upon this foundation, and in 
 like manner, confining his inquiries to the 
 law of gravitation, and the properties of 
 light, performed wonders, if he had at- 
 tempted a great deal more, he had done a 
 great deal less, and perhaps nothing at all. 
 Ambitious of following such great examples, 
 with unequal steps, alas ! andunequal force, 
 we have attempted an inquiry into one little 
 corner only of the human mind ; that cor- 
 ner which seems to be most exposed to 
 vulgar observation, and to be most easily 
 comprehended ; and yet, if we have deli- 
 neated it justly, it must be acknowledged 
 that the accounts heretofore given of it 
 were very lame, and wide of the truth." 
 
 From these observations, when compared 
 with the magnitude of the work which the 
 author lived to execute, there is some 
 ground for supposing, that, in the progress 
 of his researches, he became more and more 
 sensible of the mutual connection and de- 
 pendence which exists among the conclu- 
 sions we form concerning the various prin- 
 ciples of human nature ; even concerning 
 those which seem, on a superficial view, 
 to have the most remote relation to each 
 other : and it was fortunate for the world, 
 that, in this respect, he was induced to ex- 
 tend his views so far beyond the limits of 
 his original design. His examination, in- 
 deed, of the powers of external perception, 
 and of the questions immediately connected 
 with them, bears marks of a still more 
 minute diligence and accuracy than appear 
 in some of his speculations concerning the 
 other parts of our frame ; and what he has 
 
 written on the former subject, in liLs " In • 
 quiry into the Human ]Mind," is evidently 
 more highly finished, both in matter and 
 form, than the volumes which he published 
 in his more advanced years. The value, 
 however, of these is inestimable to future 
 adventurers in the same arduous under- 
 taking ; not only in consequence of the aids 
 they furnish as a rough draught of the field 
 to be examined, but by the example thej 
 exhibit of a method of investigation on such 
 subjects, hitherto very imperfectly under- 
 stood by philosophers. It is by the origin- 
 ality of this method, so systematically pur- 
 sued in all his researches, still more than 
 by the importance of his particular conclu- 
 sions, that he stands so conspicuously dis- 
 tinguished among those who have hitherto 
 prosecuted analytically the study of man. 
 
 I have heard it sometimes mentioned, as 
 a subject of regret, that the writers who 
 have applied themselves to this branch of 
 knowledge have, in general, aimed at a 
 great deal more than it was possible to ac- 
 complish ; extending their researches to 
 all the different parts of our constitution, 
 while a long life might be well employed in 
 examining and describing the pheiiomena 
 connected with any one particular faculty. 
 Dr Reid, in a passage already quoted from 
 his " Inquiry," migTit have been supposed 
 to give some countenance to this opinion, 
 if his own subsequent labours did not so 
 strongly sanction the practice in question. 
 The truth, I apprehend, is, that such de- 
 tached researches concerning the human 
 mind can seldom be attempted with much 
 hope of success ; and that those who have 
 recommended them, have not attended suf- 
 ficiently to the circumstances which so re- 
 markably distinguish this study from that 
 which has for its object the philosophy of 
 the material world. A few remarks in 
 illustration of this proposition seem to me 
 to be necessary, in order to justify the rea- 
 sonableness of Dr Reid's undertaking ; and 
 they will be found to apply with still greater 
 force to the labours of such as may wish 
 to avail themselves of a similar analysis in 
 explaining the varieties of human genius 
 and character, or in developing the latent 
 capacities of the youthful mind. 
 
 One consideration of a more general 
 nature is, in the first place, worthy of 
 notice ; that, in the infancy of every science, 
 the grand and fundamental desideratum is 
 a bold and comprehensive outline ; some- 
 what for the same reason that, in the cul- 
 tivation of an extensive country, forests 
 must be cleared and wildernesses reclaimed, 
 befo.e the limits of private property are 
 fixed with accuracy ; and long before the 
 period when the divisions and subdivisions 
 of separate possessions give rise to the de- 
 tails of a curious and refined husbandry.
 
 OF THOMAS IlEID, D.D. 
 
 17 
 
 The speculations of Lord Bacon embraced 
 all the objects of human knowledge. Those 
 of Newton and Boyle were confined to phy- 
 sics ; but included an astonishing range of 
 the material universe. The labours of their 
 successors, in our own times, have been 
 employed with no less zeal in pursuing 
 those more particular, but equally abstruse 
 investigations, in which they were unable 
 to engage, for want of a sufficient stock 
 both of facts and of general principles; and 
 which did not perhaps interest their curio- 
 sity in any considerable degree. 
 
 If these observations are allowed to hold 
 to a certain extent with respect to all the 
 sciences, they apply in a more peculiar 
 manner to the subjects treated of m Dr 
 Keid's writings — subjects which are all 
 so intimately connected, that it may be 
 doubted if it be possible to investigate any 
 one completely, without some general ac- 
 quaintance, at least, with the rest. Even 
 the theory of the understanding may re- 
 ceive important lights from an examination 
 of the active and the moral powers ; the 
 state of which, in the mini of every indivi- 
 dual, will be found to have a powerful in- 
 fluence on his intellectual character ; — 
 while, on the other hand, an accurate analy- 
 sis of the faculties of the understanding, 
 would probably go far to obviate the scep- 
 tical dilHculties which have been started 
 concerning the origin of our moral ideas. 
 It appears to me, therefore, that, whatever 
 be the dej)artment of mental science that 
 we propose more particularly to cultivate, 
 it is necessai-y to begin with a survey of 
 human nature in all its various parts ; 
 studying these parts, however, not so much 
 on their o\\ n account, as with a reference 
 to the applications of which our conclusions 
 are susceptible to our favourite purpose. 
 The researches of Dr Reid, when consid- 
 ered carefully inthereiatiun which they bear 
 to each other, afford numberiess illustra- 
 tions of the truth of this remark. His lead- 
 ing design was evidently to overthrow the 
 modern system of scepticism ; and, at every 
 successive step of his progress, new and 
 unexpected lights break in on his funda- 
 mental principles. 
 
 It is, however, chiefly in their practical 
 application to the conduct of the under- 
 standing, and the culture of the heart, that 
 such partial views are likely to be danger- 
 ous ; for here, they tend not only to mislead 
 our theoretical conclusions, but to counter- 
 act our improvement and happiness. Of 
 this I am so fully convinced, that the most 
 faulty theories of human nature, provided 
 only they embrace the whole of it, apj)ear 
 to me less mis-chievous in their j)robable 
 effects than those more accurate and niicro- 
 hcopical researches which are iiabitually 
 confined to one particular corner of our 
 
 constitution. It is easy to conceive tliat, 
 wiiere the attention is wholly engrossed 
 \A ith the intellectual powers, the moral prin- 
 cijiles will be in danger of running to waste ; 
 and it is no less certain, on the other hand, 
 that, by confiiiing our care to the moral 
 constitution alone, we may sutler the under- 
 standing to remain under the influence of 
 unhappy prejudices, and destitute of those 
 just and enlightened views without which 
 the worthiest dispositions are of little use, 
 either to ourselves or to society. An exclu- 
 sive attention to any one of the subordinate 
 parts of tur frame — to the culture of taste, 
 for example, or of the argumentative powers, 
 or even to the refinement of our moral sen- 
 timents and feelings — must be attended with 
 a hazard proportionally greater. 
 
 " In forming the human character," says 
 Bacon, in a passage which Lord Bolingbroke 
 has pronounced to be one of the finest and 
 deepest in his writings, " we must not proceed 
 as a statuary does in forming a statue, who 
 works sometimes on the face, sometimes on 
 the hmbs, sometimes on the folds of the 
 drapery ; but we must proceed (and it is in 
 our power to proceed) as Nature does in 
 forming a flower, or any other of her pro- 
 ductions : she throws out altogether, and 
 at once, the whole system of being, and 
 the rudiments of all tlie parts. Jiwiniunta 
 pa>;ium iimiiium 1.111, nl punt et proilucil."' 
 
 Of this passage, so strongly marked xi'ith 
 Bacon's capacious intellect, and so richly 
 adorned with his " philosophical fancy,"' I 
 will not weaken the impression by any 
 comment ; and, indeed, to those who do 
 not intuitively perceive its evidence, no 
 comment would be useful. 
 
 In what I have hitherto said of Dr Keid's 
 speculations, I have confined myself to such 
 general views of the scope of his researches, 
 and of his mode of philosophizing, as seemed 
 most likely to facilitate the perusal of his 
 works to those readers who have not been 
 much conversant with these abstract disqui- 
 sitions. A slight review of some of the more 
 important and fundamental objections w hidi 
 have been proposed to his doctrines, may, 
 I hope, be useful as a farther preparation 
 for the same course of study. 
 
 Of these objections, the four following 
 appear to me to be chiefly entitled to atten- 
 tion : — 
 
 1. That he lias assumed gratuitously, in 
 all his reasonings, that theory concerning 
 the hunuin soul which the scheme of 
 materialism calls in question. 
 
 2. That his views tend to damp tlie 
 ardour of philoso])hical curiosity, by stat- 
 ing as ultimate facts, phenomena which 
 
 » In the forcRoing paiagraph, I have liorrowcd 
 (Willi a very tiilliiig allcralmii) J.urd liolingljr' ki'i 
 Wdril", ill a iicaulidil p.-naplira-c on Hafon't icniark. 
 — Sio his " lilta cil ii I'alijul Kiiig."
 
 18 
 
 ACCOUNT OF THE LIFK AND WRITINGS 
 
 may be resolved into principles more simple 
 and general. 
 
 3. That, by an nnnocessary niultiplioa- 
 tion of ori;;inal or instinctive principles, he 
 has bronght the science of mind into a state 
 more perplexed and nnsatisfactory than 
 that in which it was left by Locke and his 
 successors. 
 
 4. That his philosophy, by sanctioning 
 an appeal from the decisions of the learned 
 to the voice of the multitude, is unfavour- 
 able to a spirit of free inquiry, and lends 
 additional stability to popular errors. 
 
 1. With respect to Dr Reid's supposed 
 assumption of a doubtful hypothesis con- 
 cerning the nature of the thinking and 
 sentient principle, it is almost sufficient for 
 me to observe, that the charge is directed 
 against that very point of his philosophy in 
 which it is most completely invulnerable. 
 The circumstance which peculiarly charac- 
 terises the inductive science of mind is, 
 that it professes to abstain from all specu- 
 lations concerning its nature and essence ; 
 confining the attention entirely to pheno- 
 mena for which we have the evidence of 
 consciousness, and to the laws by which 
 these phenomena are regulated. In this 
 respect, it difters equally, in its scope, 
 from the pneumatological discussions of the 
 schools, and from the no less visionary 
 theories so loudly vaunted by the physio- 
 logical metaphysicians of more modern 
 times. Compared with the first, it differs 
 as the inquiries of the mechanical philoso- 
 phers concerning the laws of moving bodies 
 differ from the discussions of the ancient 
 sophists concerning^the existence and the 
 nature of motion. Compared with the 
 other, the difference is analogous to what 
 exists between the conclusions of Newton 
 concerning the law of gravitation, and his 
 query concerning the invisible ether of 
 which he supposes it might possibly be 
 the effect. The facts which tliis inductive 
 science aims at ascertaining, rest on their 
 own proper evidence ; an evidence uncon- 
 nected with all these hypotheses, and which 
 would not, in the smallest degree, be 
 affected, although the truth of any one of 
 them should be fully establislied. It is not, 
 therefore, on account of its inconsistency 
 with any favourite opinions of my own, that 
 I would oppose the disquisitions either of 
 scholastic pneumatology, or of physiological 
 metaphysics ; but because I consider them 
 as an idle waste of time and genius on ques- 
 tions where our conclusions can neither be 
 verified nor overturned by an appeal to ex- 
 periment or observation. Sir Isaac New- 
 ton's query concerning the cause of gravi- 
 tation was certainly not inconsistent with 
 his own discoveries concerning its laws ; 
 but what would have been the consequences 
 
 to the world, if he had indulged himself in 
 the prosecution of hypothet cal theories with 
 respect to the tormer, instead of directing 
 his ivstonisiiiug powers to an investigation 
 of the latter ? 
 
 That the general spirit of Dr Reid » 
 philosophy is hostile to the conclusions 
 of the materialist, is indeed a fact. Not, 
 however, because his system rests on the 
 contrary hypothesis as a fundamental prin- 
 ciple, but because his inquiries have a 
 powerful tendency to wean the understand- 
 ing gradually from those obstinate associa- 
 tions and prejudices to which the common 
 mechanical theories of mind owe all their 
 plausibility. It is, in truth, much more 
 from such examples of sound research con- 
 cerning the laws of thought, than from 
 any direct metaphysical refutation, that a 
 change is to be expected in the opinions of 
 those who have been accustomed to con- 
 found together two classes of phenomena, 
 so completely and essentially different. But 
 this view of the subject does not belong to 
 the present argument. 
 
 It has been recommended of late, by a 
 medical author of great reputation, to those 
 who wish to study the human mind, to 
 begin with preparing themselves for the 
 task by the study of anatomy. I must con- 
 fess, I cannot perceive the advantages of 
 this order of investigation ; as the anatomy 
 of the body does not seem to me more likely 
 to throw light on the philosophy of the 
 mind, than an analysis of the mind to throw 
 light on the physiology of the body. To 
 ascertain, indeed, the general laws of their 
 connection from facts established by observ- 
 ation or experiment, is a reasonable and 
 most interesting object of philosophical 
 curiosity ; and in this inquiry, (which was 
 long ago proposed and recommended by 
 Lord Bacon,) a knowledge of the constitu- 
 tion both of mind and body is indispensably 
 requisite ; but even here, if we wish to pro- 
 ceed on firm ground, the two classes of iacts 
 must be kept completely distinct ; so that 
 neither of them may be warped or distorted 
 in consequence of theories suggested by 
 their supposed relations or analogies.* 
 Thus, in many of the [thenomena connected 
 with custom and habit, there is ample scope 
 for investigating general laws, both with 
 respect to our mental and our corporeal 
 frame ; but what light do we derive from 
 such information concerning this part of 
 our constitution as is contained in the fol- 
 lowing sentence of Locke ? — " Habits seem 
 to be but trains of motion in the animal 
 spirits, which, once set a-going, continue ift 
 the same steps they had been used to, 
 which, by often treading, are worn into a 
 
 » " Elements of the Philosophy of the Humab 
 Mind," pp. 11, 12. 2d edit.
 
 OF THOMAS llEID, D.D. 
 
 19 
 
 smooth patli." In like manner, the laws 
 which regulate the connection between the 
 mind and our external origans, in the case 
 of perception, have furnislied a very fertile 
 subject of evaniination to some of the best 
 of our modern philosophers ; but how im- 
 potent does the genius of Newton itself 
 appear, when it attempts to shoot the gulf 
 which separates the sensible world and the 
 sentient principle ! " Is not the sensorium 
 of animals," he asks in one of his queries, 
 " the place where the sentient substance is 
 present, and to which the sensible species 
 of things are brought through the nerves 
 and brain, that they may be perceived by 
 the mmd present in that place ?" 
 
 It ought to be remembered, also, that this 
 inquiry, with respect to the laws regulating 
 the connection between our bodily organiz- 
 ation, and the phenomena subjected to our 
 own consciousness, is but one particular 
 department of the philosophy of the mind ; 
 and that there still remains a wide, and, 
 indeed, boundless region, where all our 'lata 
 must be obtained from our own mental 
 operations. In examining, for instance, the 
 powers of judgment and reasoning, let any 
 person of sound understanding, after perus- 
 ing the observations of Bacon on the di lifer- 
 ent classes of our prejudices, or those of 
 Locke on the abuse of words, turn his atten- 
 tion to the speculations of some of our con- 
 temporary theorists, and he will at once 
 perceive the distinction between the two 
 modes of investigation which I wish at pre- 
 sent to contrast. " Reasoning," says one 
 of the most ingenious and original of these, 
 " is that operation of the npitsonum by 
 which we excite two or many tribes of ideas, 
 and then re-excite the ideas in which they 
 ditter or correspond. If we determine this 
 difference, it is called Judgment; if we in 
 vain endeavour to determine it, it is called 
 Doubting; if we re-excite the ideas in which 
 they differ, it is called Distinguishing ; if 
 we re-excite those in which they correspond, 
 it Is called Comparing."* In what accept- 
 ation the word iden is to be understood in 
 the foregoing passage, may be learned from 
 the following definition of the same author : 
 — " The word idea has various meanings in 
 the writers of metaphysic : it is here used 
 Bimply for those notions of external things 
 which our organs of sense bring us ac- 
 quainted with originally ; and is defined a 
 contraction, or motion, or configuration, of 
 the fibres which constitute the immediate 
 organ of !-ense."f Mr Hume, who was less 
 of a physiologist than Dr Darwin, has made 
 use of a language by no means so theoretical 
 and arbitrary, but still widely removed from 
 tliesimplicityand precision essentially ncccs- 
 
 • " Zoniiomi!)," vol. 1. |) 18!, a<l edit. 
 t lliiil., vol. I. pp. 11, 12. 
 
 sary in studies where everything depends 
 on the cautious use of terms. " Belief,'' 
 according to him, is " a lively idea related 
 to or associated with a present impression ; 
 IMemory is the faculty by which we repeat 
 our impressions, so as that they retain a 
 considerable degree of their first vivacity, 
 and are somewhat intermediate betwixt an 
 idea and an impression." 
 
 According to the views of Dr Reid, the 
 terms which express the simple powers of 
 the mind, are considered as unsusceptible 
 of definition or explanation ; the word.s, 
 Feeling, for example. Knowledge, Will, 
 Doubt, Belief, being, in this respect, on the 
 same footing with the words, Green or 
 Scarlet, Sw'eet or Bitter. To the names of 
 these mental operations, all men annex 
 some notions, more or less distinct ; and 
 the only way of conveying to them notions 
 more correct, is by teaching them to ex- 
 ercise their own powers of reflection. The 
 definitions quoted from Hume and Darwin, 
 even if they were more unexceptionable in 
 point of phraseology, would, for these rea- 
 sons, be unphilosophical, as attempts to 
 simplify what is incapable of analysis ; but, 
 as they are actually stated, they not only 
 envelope truth in mystery, but lay a found- 
 ation, at the very outset, for an erroneous 
 theory. It is worth while to add, that, of 
 the two theories in question, that of Darwin, 
 how inferior soever, in the estimation of 
 competent judges, as a philosophical work, 
 is by far the best calculated to impose on 
 a very wide circle of readers, by the mix- 
 ture it exhibits of crude and visionary me- 
 taphysics, with those important facts and 
 conclusions which might be expected from 
 the talents and experience of such a writer, 
 in the jiresent advanced state of medical 
 and physiological science. The questions 
 which have been hitherto confined to a few, 
 prepared for such discussions by habits of 
 philosophical study, are thus submitted to 
 the consideration, not only of the cultivated 
 and enlightened minds which adorn the 
 medical proiession, but of the half-informed 
 multitude who follow the medical trade : 
 nor is it to be doubted, that many of these 
 will give the author credit, upon subjects of 
 which they feel themselves incompetent to 
 judge, for the same ability which he dis- 
 plays within their own professional sphere. 
 The hypothetical ])rinciples assumed by 
 Humo are intelligible to those only who are 
 familiarized to the language of the schools ; 
 and his ingenuity and elegance, captivating 
 as they arc to men of taste and refinement, 
 possess slight attractions to the majority 
 of such as are most likely to be misled by 
 his conchisions. 
 
 After all, I do not apprehend that the 
 physiological theories concerning the mind, 
 which have made so much noise of late, 
 
 c2
 
 20 
 
 ACCOUNT OF THE LIFK AND WRITINGS 
 
 will produce a very lasting impression. 
 The splendour of Dr Darwin's acconiy)lis]i- 
 nients could not fail to bestow a tenipoKiry 
 importance on whateveropinioiis were sanc- 
 tioned by liis name ; as the clieniical dis- 
 coveries which have immortalized that of 
 Priestley, liave, for a while, recalled from 
 ob ivion the reveries of Hartley. But, ab- 
 stracting from these accidental instances, 
 in which human reason seems to have held 
 a retrograde course, there has certainly been, 
 since the time of Des Cartes, a continual, 
 and, on the whole, a very remarkable ap- 
 proach to the inductive plan of studyhig 
 human nature. We may trace tliis in the 
 writings even of those who profess to con- 
 sider thouyht merely as nn affita'ion ff the 
 biun—in the writings more particuhirly 
 of flume and of Helvetius ; both of whom, 
 although they may have occasionally ex- 
 pressed themselves in an unguarded man- 
 ner concerning the nature of mind, have, 
 in their mrst useful and practical disquisi- 
 tions, beeii prevented, by their own good 
 sense, from blending any theory with re- 
 spect to the ci/iises of the intellectual phe- 
 nomena with the history of facts, or the 
 investigation of general laws. The authors 
 who form the most conspicuous exceptions 
 to this gradual progress, consist chiefly of 
 men whose errors may be easily accounted 
 for, by the prejudices connected with their 
 circumscribed habits of observation and 
 inquiry : of physiologists, accustomed to 
 attend to that part alone of the human 
 frame which the knife of the anatomist 
 can lay open ; or of chemists, who enter on 
 the analysis of thought, fresh from the 
 decompositions of the laboratory — carrjdng 
 into the theory of mind itself (what Bacon 
 expressively calls) " the smoke and tarnish 
 of the furnace." Of the value of such pur- 
 suits, none can think more highly than 
 myself ; but I must be allowed to observe, 
 that the most distinguished pre-eminence 
 in them does not necessarily imply a capa- 
 city of collected and abstracted reflection, 
 or an understanding superior to the preju- 
 dices of early association, and the illusions 
 of popular language. I will not go so far 
 as Cicero, when he ascribes to those who 
 possess these advantages, a more than 
 ordinary vigour of intellect : — " Magni est 
 vigenii revccare nientem a sensib'is, et cogUu- 
 tionnn a consuetudbie abdiicerr," I would 
 only c'aim for them the merit of patient 
 and cautious research ; and would exact 
 from their antagonists the same qualifica- 
 tions." 
 
 lu offering these remarks, I have no 
 wish to exalt any one branch of useful 
 knowledge at the expense of auotlier, but 
 to combat prejudices equally fatal to the 
 
 * Note U. 
 
 progress of them all. With tlse same \ inw, 
 1 cannot help taking notice of a prevailing, 
 but very mistaken idea, that the formation 
 of ji liypothetical system is a stronger prool 
 of inventive genius than the patient in- 
 vestigation of Nature in the way of induc- 
 tion- To form a s}stem, appears to tlie 
 young and inexperienced understanding, a 
 sjjecies of creation ; to ascend slowly to 
 general conclusions, from the observation 
 and comparison of particular facts, is tc 
 conmient servilely on the works of another. 
 
 No opinion, surely, can be more ground- 
 less. To fix on a few principles, or even 
 on a single principle, as the foundation of a 
 theory ; and, by an artful statement of sup- 
 posed facts, aided by a dexterous use o) 
 language, to give a plausible explanation, 
 by means of it, of an immense number of 
 piienomena, is within the reach of most 
 men whose talents have been a little exer- 
 cised among the subtilties of the schools : 
 whereas, to follow Nature through all her 
 varieties with a quick yet an exact eye — 
 to record faithfully what she exhibits, and 
 to record nothing more — to trace, amidst 
 the diversity of her operations, the simple 
 and comprehensive laws by which they are 
 regulated, and sometimes to guess at the 
 beneficent purposes to which they are sub- 
 servient—may be safely pronounced to be 
 the highest effort of a created intelligence. 
 And, accordingly, the number of ingenious 
 theorists lias, in every age, been great ; 
 that of sound philosojihers has been won- 
 derfully small ; — or, rather, they are only 
 beginning now to have a gliniiise of their 
 way, in consequence of the combined lights 
 furnished by tlieir predecessors. 
 
 Des Cartes aimed at a complete sj'stem 
 of physics, deduced a prior i from the abstract 
 suggestions of his own reason ; Newton as- 
 pired no higher than at a faithful " inter- 
 pretation of Nature," hi a few of the more 
 general laws which she presents to our no- 
 tice: and yet the intellectual power disp'ayed 
 in the voluminous writings of the former 
 vanishes into notliing when compared with 
 what we may trace in a single page of the 
 latte'r. On this occ-:ision, a remark of Lord 
 Bacon appears singularly apposite — that 
 " Alexander and Ca;sar, though they acted 
 without the aid of magic or prodigy, per- 
 formed exploits that are truly greater than 
 what fable reports of King Arthur or Ama- 
 dis de Gaul." 
 
 I shall only add farther on this head, 
 that the last observation holds more strictly 
 with respect to the philosophy of the human 
 mind, than any other bi'anch of science ; 
 for there is no subject whatever on which 
 it is so easy to form theories calculated to 
 impose on the multitude ; and none where 
 the discovery of truth is attended with so 
 many difficulties. One great cause of tliia
 
 OF THOMAS REID, D.D. 
 
 2] 
 
 Is, the analogical or theoretical terms em- 
 ployed in ordinary language to express every 
 thing relating either to our intellectual or 
 active powers ; in consequence of which, 
 specious explanations of the most mysteri- 
 ous phenomena may be given to suiieificial 
 inquirers ; while, at the same time, the la- 
 bour of just investigation is increased to an 
 incalculable degree. 
 
 2. To allege that, in this circumscriptioD 
 of the fie d t^t' our inquiries concerning the 
 niind, there is any tendency to repress a 
 reasonable and philosophical curiosity, is a 
 charge no less unfounded than the former ; 
 inasmuch as every physical inquiry concern- 
 ing the material world is circumscribed by 
 limits precisely analogous. In call our in- 
 vestigations, whatever their subject may be, 
 the business of philosophy is confined to a 
 reference of particular facts to other facts 
 more general ; and our most successful re- 
 searches must at length terminate in some 
 law of nature, of which no explanation can 
 be given. In its application to Dr Reid's 
 writings, this objection has, I think, been 
 more pointedly directed against his reason- 
 ings concernmg the process of nature in 
 perception ; a jiart of his writings which 
 (as it is of fundamental importance in his 
 general system) he has laboured with pecu- 
 liar care. The result is, indeed, by no means 
 flattering to the pride of those thtorists who 
 profess to explain everything; ibr it amounts 
 to an acknowledgment that, after all the 
 lights w hich anatomy and physiology supply, 
 the infoinialion we obtain by means of our 
 senses, concerning the existence and the 
 qualities of matter, is no less incomprehen- 
 sible to our faculties than it ajjpears to the 
 most illiterate peasant ; and that all we 
 have gained, is a more precise and complete 
 acquaintance with some particulars in our 
 animal economy — highly interesting, indeed, 
 when regarded in their proper light, as ac- 
 cessions to our physical knowledge, but, 
 considered in connection with the jihiloso- 
 phy of the mind, afibrding only a more 
 accurate statement of the astonishing phe- 
 nomena whifh we would vainly endeavour 
 to explain. This language has been charged, 
 but most unjustly and ignorantly, with mp.s- 
 lic'Kiii ; for the same charge may be brought, 
 with equal fairness, against all the most im- 
 portant discoveries in the sciences. It was, 
 in truth, the very objection urged against 
 Newton, when his adversaries contended, 
 that yranly was to be ranked with the occult 
 (fiu/itie.s of the schoolmen, till iis mechanical 
 cause sliould be assigned ; aiid the answer 
 given to this oljcction, by Sir Isaac New- 
 ton's commentator, I\Ir IMaclaurin, may be 
 literall\ apjilied, in the instance before us. 
 to the inductive philosophy of tli(^ human 
 mind : — 
 
 " The o[iiionents of .Ncwtiii, finding no- 
 
 thing to object to his observations and reason- 
 ings, pretended to find a resemblance between 
 his doctrines and the exploded tenets of the 
 scholastic philosophy. They triumphed 
 mightily in treating gravity as an occult 
 quality, because he did not pretend to de- 
 duce this ])rineiple fully from its cause. . 
 
 . . . I know not that ever it was made 
 an objecti<in to the circuhition of the blood, 
 that there is no small difiiciilty in account- 
 ing for it mechanically. They, too, who 
 first extended gravity to air, vapour, and to 
 all bodies round the earth, had their praise ; 
 though the cause of gravity was as obscure 
 as before ; or rather ajqinnrd more m::sti - 
 tcrioiis, after they had shewn that there 
 was no body found near the earth, exempt 
 from gravity, that might be sujjposed to be 
 its cause. Why, then, were his admirable 
 discoveries, by which tliis principle was ex- 
 tended over the universe, so ill relished 
 by some philosojihers ? The truth is, he 
 had, with great evidence, overthrown the 
 boasted schemes by which they pretended 
 to unravel all the mysteries of nature ; and 
 the philosophy he mtroduced in place of 
 them, carrying with it a sincere confession 
 of our being far from a complete and perfect 
 knowledge of it, could not jilease those who 
 had been accustomed to imagine themselves 
 [lossessed of the eternal reasons and primary 
 causes of all things. 
 
 " It was, however, no new thing that 
 this philosophy should meet with opposition. 
 All the useful discoveries that were made in 
 former times, and particularly in the seven- 
 teenth century, had to struggle with the 
 prejudices of those who had accustumed 
 themselves, not so much as to think lut in 
 a certain systematic way ; who could not be 
 prevailed on to abandon their favourite 
 schemes, while they were able to imagine 
 the least pretext for continuing the dispute. 
 Every art and talent was di^)^layed to su] - 
 port their falling cause; no aid seenud 
 foreign to them that could in any manner 
 annoy their adversary ; and such often was 
 their obstinacy, that truth was able to male 
 little progress, till they were succeeded by 
 younger persons, who had not so strongly 
 imbibed their prejiid ces." 
 
 These excellent observations are not the 
 less applicable to the subject now under 
 consideration, that the jiart of Dr Reid's 
 writings which suggested the quotation, 
 loads only to the correction of an uiveterate 
 jirejudicc, not to any new general conclu- 
 sion. It is ])robable, indeed, (now that the 
 ideal theory has, in a great measure, dis- 
 apjjcared from our late metai>hysical sys- 
 tems,) that those who have a jiliasure in 
 detracting from the merits of their prede- 
 cessors, may be disposed to represent it as 
 iin idle waste of labour and ingenuity to luno 
 entered into a serious refutation of a hyiKi-
 
 22 
 
 ACCOUNT OF THE LIFE AND WRIT[NGS 
 
 thesis at once gratuitous and inconceivable. 
 A different judgment, however, will be 
 formed by such as are acquainted with the 
 extensive influence which, from the ear- 
 liest accounts of science, this single preju- 
 dice has had in vitiating almost every 
 branch of the philosojjhy of the mind ; and 
 who, at the same time, recollect the names 
 of the illustrious men by whom, in more 
 modern times, it has been adopted as an 
 incontrovertible principle. It is sufficient 
 for me to mention those of Berkeley, Hume, 
 Locke, Clarke, and Newton. To the two 
 first of these, it has served as the basis of 
 their sceptical conclusions, which seem, in- 
 deed, to follow from it as necessary conse- 
 quences ; while the others repeatedly refer 
 to it in their reasonings, as one of those 
 facts concerning the mind of which it 
 would be equally superfluous to attempt a 
 proof or a refutation. 
 
 I havt enlarged on this part of Dr 
 Reid's writings the more fully, as he was 
 himself disposed, on all occasions, to rest 
 upon it his chief merit as an author. In 
 proof of this, I shall transcribe a few sen- 
 tences from a letter of his to Dr Gregory, 
 dated 20th August 1790 :— 
 
 " It would be want of candour not to 
 cwn that I think there is some merit in 
 what you are pleased to call my Philoso- 
 phy ; but I think it lies chiefly in having 
 called in question the common theory of 
 Ideas, or Images of things in ihe mind being 
 the only objects of thought ; a theory 
 founded on natural prejudices, and so uni- 
 versally received as to be interwoven with 
 the structure of language. Yet, were I to 
 give you a detail of what led me to call in 
 question this theory, after I had long held 
 it as self-evident and unquestionable, you 
 would think, as I do, that there was much 
 of chance in the matter. The discovery 
 was the birth of time, not of genius ; and 
 Berkeley and Hume did more to bring it 
 to light than the man that hit u]5on it. I 
 think there is hardly anything that can be 
 called mine in the philosophy of the mind, 
 which does not foUov/ with ease from the 
 detection of this prejudice. 
 
 " I must, therefore, beg of you most ear- 
 nestly, to make no contrast in my favour 
 to the disparagement of my predecessors 
 in the same pursuit. I can truly say of 
 them, and shall always avow, what you are 
 pleased to say of me, that, but for the 
 assistance I have received from their writ- 
 ings, I never could have wrote or thought 
 what I have done." 
 
 3. Somewhat connected with the last 
 objection, are the censures which have been 
 so frequently bestowed on Dr Reid, for an 
 unnecessary and un systematical multiplica- 
 tion of original or instinctive principles. 
 
 In reply to these censures, I have httle 
 
 to add to what I have remarked on the 
 same topic, in the " Philosophy of the 
 Human JNJind." That the fault which is 
 thus ascribed to Dr Reid has been really 
 committed by some ingenious writers in 
 this part of the island, 1 most readily allow ; 
 nor will I take upon me to assert that he 
 has, in no instance, fallen into it himself. 
 Such instances, however, will be found, on 
 an accurate examination of his works, to 
 be comparatively few, and to bear a very 
 trifling proportion to those in which he has 
 most successfully and decisively displayed 
 his acuteness in exposing the premature 
 and flimsy generalizations of his prede- 
 cessors. 
 
 A certain degree of leaning to that ex- 
 treme to which Dr Reid seems to have 
 inclined, was, at the time when he wrote, 
 much safer than the opposite bias. From 
 the earliest ages, the sciences in general, 
 and more particularly the science of the 
 human mind, have been vitiated by an 
 undue love of simplicity ; and, in the course 
 of the last century, this disposition, after 
 having been long displayed in subtle theo- 
 ries concerning the active powers, or the 
 principles of human conduct, has been 
 directed to similar refinements with resrcct 
 to the faculties of the understanding, u.ud 
 the truths with which they are conversant. 
 Mr Hume himself has coincided so far with 
 the Hartleian school, as to represent the 
 "principle of union and cohesion among 
 our simple ideas as a kind of attraction, of 
 as universal application in the mental 
 world as in the natural ;"* and Dr Hartley, 
 with a still more sanguine imagination, 
 looked forward to an era '' when future 
 generations shall put all kinds of evidences 
 and inquiries into mathematical forms ; 
 reducing Aristotle's ten categories, and 
 Bishop Wilkin's forty summa genera, to 
 the head of quantity alone, so as to make 
 mathematics and logic, natural history and 
 civil history, natural philosophy and philo- 
 sophy of all other kinds, coincide, omni ex 
 parte.^'f 
 
 It is needless to remark the obvious ten- 
 dency of such premature generalizations, 
 to withdraw the attention from the study of 
 particular phenomena ; while the effect of 
 Reid's mode of philosophizing, even in 
 those instances where it is carried to an ex- 
 cess, is to detain us, in this preliminary 
 step, a little longer than is absolutely ne- 
 cessary. The truth is, that, when the 
 phenomena are once ascertained, generaliz- 
 ation is here of comparatively little value, 
 and a task of far less difficulty than to 
 observe facts with precision, and to record 
 them with fairness. 
 
 • " 'I'reatise of Human Nature," vol. i. p. ."0. 
 f Hartley " On Man," p. 207, 4to edit. London, 
 1791.
 
 OF THOMAS REID, D.D. 
 
 23 
 
 In no part of Dr Reid's writings, I am 
 inclined to think, could more plausible criti- 
 cisms be made on this ground, than in his 
 classification of our active principles : but, 
 even there, the facts are always placed 
 fully and distinctly before the reader. That 
 several of the benevolent affections which 
 he has stated as ultimate facts in our con- 
 stitution, might be analyzed into the same 
 general principle differently modified, ac- 
 cording to circumstances, there can, in my 
 opinion, be little doubt. This, however, 
 (as I have elsewhere observed,*) notwith- 
 standing the stress which has been some- 
 times laid upon it, is chiefly a question 
 of arrangement. Whether we suppose 
 these affections to be all ultimate facts, or 
 some of tliem to be resolvable into other 
 facts more general, they are equally to be 
 regarded as constituent parts of human 
 nature ; and, upon either supposition, we 
 have equal reason to admire the wisdom 
 with which that nature is adapted to the 
 situation in which it is placed. The laws 
 which regulate the acquired perceptions of 
 sight, are surely as much a part of our 
 frame as those which regulate any of our 
 original perceptions ; and, altliough they 
 require, for their developement, a certain 
 degree of experience and observation in 
 the individual, the uniformity of the result 
 shews that there is nothing arbitrary nor 
 accidental in their origin. In this point of 
 view, what can be more philosojiliical, as 
 well as beautiful, than the words of Mr 
 Ferguson, that " natural affection springs 
 up in the soul of the motiier, as the milk 
 springs in her breast, to furnish nourish- 
 ment to her child !" "The effect is here 
 to the race," as the same author has excel- 
 lently observed, " what the vital motion of 
 the heart Ls to the individual ; too neces- 
 sary to tlie preservation of nature's works, 
 to be intrusted to the precarious will or 
 intention of those most nearly concerned, "f 
 
 The question, indeed, concerning the 
 origin of our different affections, leads to 
 some curious analytical disquisitions ; but 
 is of very subordinate importance to tliose 
 inquiries which relate to their laws, and 
 uses, and mutual references. In many 
 ethical systems, however, it seems to have 
 been consiilered as the most interesting 
 subject of (hsfjuisition which this wonder- 
 ful part of our frame presents. 
 
 In Dr Reid's "Essays on the Intellec- 
 tual Powers of Man," and in his "Inquiry 
 into the Human Mind,'' I recollect little 
 
 • " Outlines of Moral Philosopliy," pp. 79, Sri, 
 2d edit. Edinburf^h, IHdI. 
 
 t " Principles of Moral and Political Science," 
 p«rt I. cha|i. 1. sect. '.i. " (Jt I lie Principlcnol Society 
 in Homan Nature." 'J'hcwliolf dincvukion uiivtCB, in 
 » sinRular dcprec, the iioiii de«t philoso),hy with the 
 nnoiil ckiqueDt desmption. 
 
 that can justly incur a similar censure, 
 notwithstanding the ridicule which Dr 
 Priestley has attempted to throw on the 
 last of these performances, in his " Table 
 of Reid's Instmctive Principles."* To 
 examine all the articles enumerated in that 
 table, would require a greater latitude of 
 disquisition than the limits of this memoir 
 allow ; and, therefore, I shall confine my 
 observations to a few instances, where the 
 precipitancy of the general criticism seems 
 to me to admit of little dispute. In this 
 light I cannot help considering it, when 
 applied to those dispositions or determma- 
 tions of the mind to which Dr Reid has 
 given the names of the " Principle of 
 Credulity," and the " Principle of Vera- 
 city." How far these titles are happily 
 chosen, is a question of little moment ; 
 and on that point I am ready to make 
 every concession. I contend only for 
 what is essentially coimected with the 
 objection which has given rise to these 
 remarks. 
 
 " That any man," says Dr Priestley, 
 " should imagine that a peculiar instinctive 
 principle was necessary to explain our 
 giving credit to the relations of others, 
 appears to me, who have been used to see 
 things in a different light, very extraordi- 
 nary ; and yet this doctrine is advanced by 
 Dr Reid, and adopted by Dr Beattie. But 
 really," he adds, " what the former says iji 
 favour of it, is hardly deserving of the 
 slightest notice."-)- 
 
 The passage quoted by Dr Priestley, in 
 justification of this very peremptory deci- 
 sion, is as follows : — " If credulity were the 
 effect of reasoning and experience, it must 
 grow up and gather strength in the same 
 proportion as reason and experience do. 
 But, if it is the gift of nature, it will be 
 the strongest in childhood, and limited and 
 restrained by experience ; and the most 
 superficial view of human life shews that 
 this last is the case, and not the first.'' 
 
 To my own judgment, this argument of 
 Dr Reid's, when connected with the ex- 
 cellent illustrations which accompany it, 
 carries complete conviction ; and I am con- 
 firmetl in my opinion by finding, that Mr 
 Smith (a writer inferior to none in acute- 
 ness, and strongly disposed, by the peculiar 
 bent of his genius, to simplify, as far as 
 possible, the philosoiihy of human nature) 
 has, in the latest edition of his " Theory 
 of Moral Sentiments," acquiesced in tliis 
 very conclusion ; urging in support of it 
 the same reasimiiig which Dr Priestley 
 affects to estimate so lightly. " Tliere 
 seems to be in young children an instinctive 
 
 * Examination ol' Reid's " Inquiry," \o. London 
 1774. 
 f Kxamiiiatlon of Rrld's '• Iiiijiiiry," Ac, p. 88.
 
 24 
 
 ACCOUNT OF THE LIFE AND WRITINGS 
 
 disposition to believe whatever they are 
 told. Nature seems to have judfjed it ne- 
 cessary for their preservation that they 
 should, for some time at least, ])ut implicit 
 confidence in tiMse to wlioiu the care of 
 their childhood, and of the earliest and 
 most necessary part of their education, is 
 intrusted. Their credulity, ar-cordin;jfiy, is 
 excessive ; and it ro([uires lonj; and much 
 experience of the falsehood of mankind to 
 reduce tliein to a reasonable degree of ditH- 
 dence and distrust."* That Mr Smitli's 
 opinion also coincided with Dr Reid's, in 
 what he has stated concerning the principle 
 of veraciti/, appears evidently from the 
 remarks which immediately follow the pas- 
 sage just quoted. But I must not add to 
 the length of this memoir by uunecessary 
 citations. 
 
 Another instinctive principle mentioned 
 by Reid, is " our belief of the continuance 
 of the present course of uature." " All our 
 knowledge of nature,'' he observes, " be- 
 yond our original perceptions, is got by 
 experience, and consists in the interpreta- 
 tion of natural signs. The appearance of 
 the sign is followed by the belief of the 
 thing signified. Upon this principle of our 
 constitution, not only acquired perception, 
 but also inductive reasoning, and all rea- 
 soning from analogy, is grounded ; and, 
 therefore, for want of a better name, we 
 shall beg leave to call it the inductive prin- 
 ciple. It is from the force of this principle 
 that we immediately assent to that axiom 
 upon which all our knowledge of nature is 
 built, that eff'ects of the same kind must 
 liave the same cause. T.dce away the 
 light of this inductive principle, and ex- 
 perience is as blind as a mole. She may 
 indeed feel what is present, and what im- 
 mediately touches her, but she sees nothing 
 that is either before or behind, upon the 
 right hand or upon the left, future or 
 past." 
 
 On this doctrine, likewise, the same 
 critic has exi^ressed himself with much 
 severity ; calluig it " a mere quibble ;" 
 and adding, " every step that I take among 
 this writer's sophisms, raises my astonish- 
 ment higher than before." In this, how- 
 ever, as in many other mstances, he has 
 been led to censure Dr Reid, not because 
 he was able to see farther than his antago- 
 nist, but because he. did uot see quite so 
 far. Turgot, in an article inserted in tlie 
 French " Encyclop&lie," and Condorcet, in 
 a discourse prefixed to one of his mathe- 
 matical publications,t have, both of them, 
 stated the fact with a true philosophical 
 precision ; and, after doing so, have de- 
 
 * Smith's "Theory," last edit, part VII. sect I. 
 
 t " Ks^ai sur Tap ilicitioii tie I'anaiv.'ie ii la pro- 
 bahilit6 (ies 'lecision's riniliics h la iiliiralile dos 
 voix." Psris, ns.'i. 
 
 duced from it an inference, not .jfny the 
 same ui substance with that of Dr Reid, 
 ijut almost expressed in the same form of 
 words. 
 
 In these references, as well as in that 
 already made to Mr Smith's " Theory," I 
 would not be understood to lay any undue 
 stress on authority in a philosophical argu- 
 ment. I wish only — by contrasting tiie 
 modesty and caution restdtiiig from habits 
 of profound thought, with that theoretical 
 intrepidity which a blindness to insuper- 
 able difficulties has a tendency to inspire — 
 to invite those whose prejudices against this 
 part of Reid's system rest chiefly on the 
 great names to which they conceive it to 
 be hostile, to re-examine it with a little 
 more attention, before they pronounce 
 finally on its merits. 
 
 The prejudices which are apt to occur 
 against a mode of philosophizing so morti- 
 fying to scholastic arrogance, are encour- 
 aged greatly by that natural disposition, to 
 refer particular facts to general laws, which 
 is the foundation of all scientific arrange- 
 ment ; a principle of the utmost importance 
 to our intellectual constitution, but which 
 requires the guidance of a sound and ex- 
 perienced understanding to accomplish the 
 purposes for which it was destined. They 
 are encouraged also, in no inconsiderable 
 degree, by the acknowledged success of 
 mathematicians, in raising, on the basis of a 
 few simple da/a, the most magnificent, and, 
 at the same time, the most solid fabric of 
 science, of which human genius can boast. 
 The absurd references which logicians are 
 accustomed to make to Euclid's " Elements 
 of Geometry,'' as a model which cannot be 
 too studiously copied, both in physics and 
 in morals, have contributed, in this as in a 
 variety of other instances, to mislead phi- 
 losophers from the study of facts, into the 
 false refinements of hypothetical theory. 
 
 On these misapplications of mathemati- 
 cal method to sciences which rest ulti- 
 mately on experiment atid observation, I 
 shall take another opportunity of offering 
 some strictures. At ])resent, it is suffi- 
 cient to remark the peculiar nature of the 
 truths about which pure or abstract mathe- 
 matics are conversant. As these truths 
 have all a necessary connection with each 
 other, (all of them resting ultimately on 
 those definitions or hypotheses which 
 are the principles of our reasoning,) the 
 beauty of the science cannot fail to increase 
 in proportion to the siaiplicity of the 'h/ia, 
 compared with th.e incalculable variety of 
 consequences which they involve : and to 
 the simplific.ntions and generalizations of 
 theory on sucii a subject, it is perhaps im- 
 possible to conceive any limit. How dif- 
 ferent is the Ciise in those inquiries wliere 
 our first principles are not definitions but
 
 OF THOMAS REID, D.D. 
 
 26 
 
 fad.- , aud wnere our business is not to 
 trace necessary coiiuections, but the laws 
 which regulate the established order of the 
 universe ! 
 
 In various attempts which have been 
 lately made, more especially on the Conti- 
 nent", towards a systematical exposition of 
 the elements of physics, the eftects of the 
 mistake I am now censuring are extremely 
 remarlvable. The happy use of mathema- 
 tical principles, exhibited in the writings 
 of Newton and his followers, having ren- 
 dered an extensive knowledge of them an 
 indispensable pre|iaratii>n for the study of 
 the mechanical philosophy, the early habits 
 of thouglit acquired in the former pursuit 
 are naturally tiansferred to the latter. 
 Hence the illogical aud obscure manner in 
 which its elementary principles have fre- 
 quently beeu stated ; an attempt being 
 made to deduce, from the smallest possible 
 imndier of dai<i, the whole system of truths 
 which it comprehends. Tlie analogy exist- 
 ing among some of the fundamental laws of 
 mechanics, bestows, in the opinion of the 
 multitude, an appearance of plausibility on 
 such attempts ; and their obvious tendency 
 is to withdraw the attention from that unity 
 of design which it is the noblest employ- 
 ment of philosophy to illustrate, by dis- 
 guising it under the semblance of an eter- 
 nal and nccessai'y order, similar to what 
 the mathematician delights to trace among 
 the mutual relations of quantities aud 
 figures. 
 
 These slight hints may serve as a reply hi 
 ])art to what Dr Priestley has suggested 
 witli respect to the coiisequences likely to 
 follow, if the sjiirit of Reid's philosophy 
 should be introduced into physics.* One 
 consequence would unquestionably be, a 
 careful separation between the ])rinciples 
 which we learn from ex])erience alone, and 
 those which are fairly resolvable, by ma- 
 thematical or physical reasoning, into other 
 facts still more general ; and, of course, a 
 correction of that false logic which, wh.ile 
 it throws an air of mystery over the jilainest 
 and most undeniable facts, levels the study 
 of nature, in point of moral interest, with 
 the investigations of the geometer or of the 
 algebraist. 
 
 It must not, however, be sujtposed, that, 
 in the present state of natural philosophy, 
 a false logic threatens the same dangerous 
 effects as in the philosoidiy of the mind. 
 It may retard somewhat the progress of the 
 student at his first outset ; or it may con- 
 found, in his ap[irehensions, the harmony 
 of systematical onler with the consistency 
 and mutual dependt-ncy essential to a series 
 of matheniatical theorems : but the funda- 
 mental truths of physics are now too well 
 
 ♦ " Examination nl Ueld'a Inquiry, p liO. 
 
 ! established, and the checks which it fur- 
 nishes against sophistry are too numerous 
 and palpable, to admit the possibility of any 
 permanent error in our deductions. In the 
 philosophy of the mind, so difficult is the 
 acquisition of those habits of reflection 
 which can alone lead to a correct knowledge 
 of the intellectual p/iteiomeni/^ that a faulty 
 hypothesis, if skilfully fortified by the im- 
 posing, though illusory strength of arbitrary 
 definitions and a systematical phraseology, 
 nuiy maintaiu its ground for a succession 
 of ages. 
 
 It will not, I trust, be inferred from 
 anything I have here advanced, that I 
 mean to offer an apology for those who, 
 either in physics or morals, would pre- 
 sumptuously state their own opinions with 
 resjiect to the laws of nature, as a bar 
 against future attempts to simplify and 
 generalize them still farther. To assert 
 that none of the mechanical explanations 
 yet given of gravitation are satisfactory, 
 and even to hint that ingenuity mi ht be 
 more profitably emjiloyed than in the search 
 of sucli a theory, is something difierent from 
 a gratuitous assumption of utimate facts in 
 physics ; nor does it imply an obstinate de- 
 termination to resist legitimate evidence, 
 should some fortunate inquirer — contrary 
 to what seems probable at present - succeed 
 where the genius of Newton has failed. If 
 Dr lieid has gone farther than this in his 
 conclusions concerning the principles which 
 iie calls original or instinctive, he has de- 
 parted from that guarded language in which 
 he counuonly exi)resses himself— for all that 
 it was ot importance for him to conclude 
 was, that the theories of his predecessors 
 were, in these instances, exceptionable ; 
 and the doubts he niay occasionally insinu- 
 ate, concerning the success of future adven- 
 turers, so far fri>m betraying any overween- 
 ing confidence in his own understanding, 
 arc an indirect tribute to the talents of those 
 from who-e failure he draws an aiguineiit 
 against the possibility of their undertaking. 
 
 The same eagerness to simplify and to 
 generalize, which led Priestley to complain 
 of the number of Reid's instinctive prin- 
 ciples, has carried some later philosophers 
 a step farther. According to them, the 
 very word iiislinrl is unipliiUisojihical ; and 
 everything, either in man or brute, which 
 has been hitherto referred to this mysteri- 
 ous source, may be easily accounted lor by 
 experience or imitation. A few instances 
 in which this doctrine aiqioars to have been 
 successfully verified, have been deemed 
 sufficient to establish it without any lindt- 
 ation. 
 
 In a very original work, on which I have 
 already hazarded some criiicisms, much in- 
 genuity has been employed in analyzing the 
 wonderful efforts which the human infant
 
 26 
 
 ACCOUNT OF THE LIFE AND WRITINGS 
 
 is enabled to make for its own preservation 
 the moment after its introduction to the 
 liffht. Thus, it is observed that thefce'us, 
 while still in the vtfiu.s, learns to perform 
 the operation of swallowing ; and also learns 
 to relieve itself, by a change of posture, 
 from the irksomenoss of continued rest : 
 and, therefore, (if we admit these proposi- 
 tions,) we must conclude that some of the 
 actions which infants are vulgarly supposed 
 to perform in conscijuence of instincts coeval 
 with birth, are only a continuation of actions 
 to which they were determined at an earlier 
 period of their being. The remark is inge- 
 nious, and it may perhaps be just ; but it 
 does not prove that inxli net is an nnphiloso- 
 phical term ; nor does it render the opera- 
 tions of the infant less mysterious than they 
 seem to be on the common supposition. 
 How far soever the analysis, in such in- 
 stances, may be carried, we must at last 
 arrive at some p/iiBnumeuon no less wonder- 
 ful than that we mean to explain : in other 
 words, we must still admit as an ultimate 
 fact, the existence of an original determina- 
 tion to a particular mode of action salutary 
 or necessary to the animal ; and all we 
 have accomi)lished is, to connect the origin 
 of this instinct with an earlier period in the 
 history of tlie human mind. 
 
 The same author has attempted to ac- 
 count, in a manner somewhat similar, for 
 the different degrees in which the young 
 of ditterent animals are able, at the moment 
 of birth, to exert their bodily powers. 
 Thus, calves and chickens are able to walk 
 almost immediately ; while the human in- 
 fant, even in the most favourable situations, 
 is six or even twelve months old before he 
 can stand alone. For this Dr Darwin 
 assigns two causes. 1. That the young of 
 some animals come into the world in a more 
 complete state than that of others- the colt 
 and lamb, for example, enjoying, in this 
 respect, a striking advantage over the puppy 
 and the rabbit. 2. That the mode of walk- 
 ing of some animals, coincides more per- 
 fectly than that of others, with the previous 
 motions of the y(B'(/»i;/ u/ero. The struggles 
 of all animals, he observes, in the womb, 
 must resemble their manner of swimming, 
 as by this kind of motion they can best 
 change their attitude in water. But the 
 swinuning of the calf and of the chicken 
 resemblos their ordinary movements on the 
 ground, wliicli they have thus learned in 
 part to execute while concealed from our 
 observation ; whereas, the swimming of the 
 human infant differing totally from his 
 manner of walking, he has no opportunity 
 of acquiring the last of these arts till he is 
 exposed to" our view. The theory is ex- 
 tremely plausible, and does honour to the 
 author's sagacity ; but it only places in a 
 new light that provident care which Nature 
 
 has taken of all her offspring in the infancy 
 of their existence. 
 
 Another instance may contribute towards 
 a more ample illustration of the same sub- 
 ject. A lamb, not many minutes after it 
 is dropped, jiroceeds to search for its nour- 
 ishment in that spot where alone it is to be 
 found ; apjdy ing both its limbs and its eyes to 
 their resjiective oflices. The peasant ob- 
 serves the fact, and gives the name of iii- 
 sliuct, or some corresponding term, to the 
 unknown principle by which the animal is 
 guided. On a more accurate examination 
 of circumstances, the philosopher finds 
 reason to conclude that it is by the sense 
 of smelling it is thus directed to its object. 
 In proof of this, among other curious facts, 
 the following has been quoted : — " On 
 dissecting," says Galen, " a goat great 
 witli young, I found a brisk emhri/on, and 
 having detached it from the matii.r, and 
 snatching it away before it saw its dam, I 
 brought it into a room where there were 
 many vessels ; some filled with w ine, others 
 with oil, some with lioney, others with 
 milk, or some other liquor ; and in others 
 there were grains and fruits. We first ob- 
 served the young animal get upon its feet 
 and walk ; then it shook itself, and after- 
 wards scratched its side with one of its 
 feet ; then we saw it smelling to every one 
 of those things that were set in the room ; 
 and, when it had smelt to them all, it 
 drank up the milk." ' Admitting this very 
 beautiful story to be true, (and, for niy own 
 part, I am far from being disposed to ques- 
 tion its probability,) it only enables us to 
 state the fact with a little more precision, 
 in consequence of our having ascertained, 
 that it is to the sense of smelling the in- 
 stinctive determination is attached. The 
 conclusion of the peasant is not here at 
 variance with that of the philosopher. _ It 
 differs only in this, that he expresses him- 
 self in those general terms which are suited 
 to his ignorance of the particular process 
 by which Nature, in this case, accomplishes 
 her end ; and, if he did otherwise, he 
 would be censurable for prejudging a ques- 
 tion of which he is incompetent to form an 
 accurate opinion. 
 
 The application of these illustrations to 
 some of Dr Reid's conclusions concerning 
 the instinctive principles of the human 
 mind, is, I flatter myself, sufficiently mani- 
 fest. They relate, indeed, to a subject 
 which differs, in various respects, from that 
 which has fallen under his more particular 
 consideration ; but the same rules of \A\\\o- 
 sophizing will be found to apply equally to 
 both. 
 
 4. The criticisms which have been made 
 on what Dr Reid has written concerning 
 
 • Darwin, vol. i pp. 190, 196.
 
 OF THOMAS REID, D.D. 
 
 27 
 
 the intuitive truths which he distinguishes 
 by the title of " Principles of Common 
 Sense," would require a more ample dis- 
 cussion than I can now bestow on them ; 
 not that the importance of these criticisms 
 (of such of them, at least, as I have happened 
 to meet with) demands a long or elaborate 
 refutation, but because the subject, accord- 
 ing to the view I wish to take of it, involves 
 some other questions of great moment and 
 difficulty, relative to the foundations of 
 human knowledge. Dr Priestley, the most 
 formidable of Dr Eeid's antagonists, has 
 granted as much in favour of this doctrine 
 as it is worth while to contend for on the 
 present occasion. " Had these writers," 
 he observes, with respect to Dr Reid and 
 his followei"s, " assumed, as the elements 
 of their Common Sense, certain truths which 
 are so plain that no man could doubt ol 
 them, (without entering into the ground ol 
 our assent to them,) their conduct would 
 have been liable to very little objection. All 
 that could have been said would have been, 
 that, without any necessity, they had made 
 an innovation in the received use of a term ; 
 for no person ever denied that there ai-e 
 self-evident truths, and that these must be 
 assumed as the foundation of all our reason- 
 ing. I never met with any person who did 
 not acknowledge this, or heard of any argu- 
 mentative treatise that did not go upon the 
 supposition of it."* After such an acknow- 
 ledgment, it is impossible to forbear asking, 
 (with Dr Campbell,) " What is the great 
 point which Dr Priestley would controvert ? 
 Is it, whether such self-evident truths shall 
 be denominated Principles of Common Sense, 
 or be distinguished by some other appella- 
 tion ?"t 
 
 That the doctrine in question has been, 
 in some publications, presented in a very 
 exceptionable form, I most readily allow ; 
 nor would I be understood to subscribe to 
 it im[)licitly, even as it appears in the works 
 of Dr Reid. It is but an act of justice to 
 him, however, to re(iuest that his ojiinions 
 may be judged of from his own works alone, 
 not from those of others who may have 
 happened to coincide with him in certain 
 tenets, or in certain modes of expression ; 
 and that, before any ridicule be attempted 
 on his conclusions concerning the authority 
 of Common Sense, his antagonists would 
 take the trouble to examine in what accept- 
 ation he has employed that phrase. 
 
 The truths which Dr Reid seems, in most 
 instances, disposed to refer to the judgment 
 of this tribunal, niiglit, in my o])inion, be 
 denominated more \niexceptionably, " fun- 
 damental laws of human belief." They 
 
 • " Examination of Dr Ueid's Inquiry," &c. p. 
 
 + " Philoiophy of nhtlonc," v(.l. i. p. 1 1 1 .— Sec 
 Niilc F, 
 
 have been called by a very ingenious fo- 
 reigner, (^r. Trembley of Geneva,) but 
 certainly with a singular infelicity of lan- 
 guage, Prcjiifjtn Luiitimrs. Of this kind 
 are the following propositions : — " I am the 
 same person to-day that I was yesterday ;" 
 " The material world has an existence in- 
 dependent of that of percipient beings ;" 
 " There are other intelligent beings in the 
 universe beside myself ;" " The future 
 course of nature will resemble the past." 
 Such truths no man but a philosopher ever 
 thinks of stating to himself in words ; but 
 all our conduct and all our reasonings pro- 
 ceed on the supposition that they are admit- 
 ted. The belief of them is essential for the 
 preservation of our animal existence ; and 
 it is accordingly coeval with the first opera- 
 tions of the intellect. 
 
 One of the first writers who introduced 
 the phrase Common Sense into the tech- 
 nical or appropriate language of logic, was 
 Father Buffier, in a book entitled, " Tmili^ 
 ■Irs l-'rcnue.ies Veriles.'''' It has since been 
 auo])ted by several authors of note in this 
 country ; particularly by Dr Reid, Dr Os- 
 wald, and Dr Beattie ; by all of whom, 
 however, I am afraid, it must be confessed, 
 it has been occasionally employed without 
 a due attention to precision. The last of 
 these writers uses it* to denote that power 
 by which the mind perceives the truth of 
 any intuitive proposition ; whether it be an 
 axiom of abstract science ; or a statement 
 of some fact resting on the immediate inform- 
 ation of consciousness, of perception, or 
 of memory ; or one of those fundamental 
 laws of belief which are implied in the ap- 
 plication of our faculties to the ordinary 
 business of life. The same extensive use 
 of the word may, I believe, be found in 
 the other authors just mentioned. But no 
 authority can justify such a laxity in tlie 
 employment of language in philosophical 
 discussions ; for, if mathematical axioms be 
 (as they are, manifestly and indisputably) 
 a class of propositions essentially distinct 
 Irom the other kinds of intuitive truths 
 now described, why refer them all indis- 
 criminately to the same principle in our 
 constitution ? If this jdirase, therefore, be 
 at all retained, precision requires that it 
 should be employed in a more limited ac- 
 eepiution ; and, accordingly, in the works 
 under our consideration, it is appropriated 
 most frequently, though by no means uni- 
 formly, to that class of intuitive truths 
 which I have already called " fundamental 
 laws of belief.''i- When thus restricted, 
 it conveys a notion, unambiguous, at least, 
 
 • " Fssay on Truth," aiition second, p. 40, el 
 Srq. ; also p KUi, ft srq. 
 
 t This seems to \w nearly the meaning annexed to 
 the plirase, by the learned and acute author of " The 
 Thilo-^ophy of lihetonc," vul i p lO'J, ct srq.
 
 28 
 
 ACCOUNT OF THE LIFE AND WRITJNGS 
 
 and definite ; and, consequently, tlie ques- 
 tion about its i)r()|)riety or ini propriety 
 turns entirely on tlio coincidence of this 
 definition with tlie meaning of the word as 
 employed in ordinary discourse. What- 
 ever objections, therefore, may be stated 
 to the expression as now defined, will 
 apply to it with ailditio al force, when used 
 with the latitude wliieh has been already 
 censured. 
 
 I have said that the question about the 
 propriety of the phrase Couinion Sense as 
 employed by jihilosophers, must be decided 
 by an appeal to general practice ; for, 
 although it be allowable, and even neces- 
 sary, for a ]duloso])her to limit the accepta- 
 tion of words which are employed vaguply 
 in common discourse, it is always dangerous 
 to give to a word a scientific meaning 
 essentially distinct from that in which it is 
 usually understood. It has, at least, the 
 effect of misleading those who do not enter 
 deeply into the subject ; and of giving a 
 paradoxical appearance to doctrines which, 
 if expressed in more unexceptionable terms, 
 would be readily admitted. 
 
 It appears to me tliat this has actually 
 happened in the present instance. The 
 phrase Common Sense, as it is generally 
 understood, is nearly synonymous with 
 rncther-wit; denoting that degree of sagacity 
 (depending partly on original capacity, and 
 partly on personal experience and observa- 
 tion) which qualifies an individual for those 
 simple and essential occupations which all 
 men are called on to exercise habitually by 
 their common nature. In this acceptation, 
 it is opposed to those mental acquiiements 
 which are derived from a regular education, 
 and from the study of books; and refers, not 
 to the speculative convictions of the under- 
 standing, but to that prudence and discretion 
 which are the foundation of successful con- 
 duct. Such is the idea which Pope annexes 
 to the word, when, speaking of good sense, 
 (which means only a more than ordinary 
 share of common sense,) he calls it — • 
 
 " Thp gilt of floaven. 
 And, though no science, (airly uortli the seven." 
 
 To speak, accordingly, of appealing from 
 the conclusions of philosophy to connnon 
 sense, had the appearance, to title-page 
 readers, of appealing from the verdict of tlie 
 learned to the voice of the multitude ; or of 
 attempting to silence free discussion by a 
 reference to .'•onie arbitrary and undofiiiable 
 standard, distinct from any of the intel- 
 lectual powers hitherto enumerated by logi- 
 cians. Whatever countenance may be sup- 
 posed to have been given by some writers 
 to such an interpretation of this doctrine, I 
 may venture to assert that none is afforded 
 by the worlis of Dv Reid. The standard to 
 which he appeals is neit'ier the creed of a 
 particular sect, nor the inward light of 
 
 enthusiastic presumption, but that constitu- 
 tion of human nature without which all the 
 business of the world would immediately 
 cease ; and the substance of his argument 
 amounts merely to this, that those essential 
 laws of belief to which sceptics have 
 objected, when considered in connection 
 with our scientific reasonings, are implied in 
 every step we take as active beings ; and if 
 called in question by any man in his prac- 
 tical concerns would expose him universally 
 to the charge of insanity. 
 
 In stating this important doctrine, it were 
 perhaps to be wished that the subject had 
 been treated with somewhat more of ana- 
 lytical accuracy ; and it is certainly to be 
 regretted that a phrase should have been 
 employed, so well calculated by its ambiguity 
 to furnish a convenient handle to misre- 
 presentations; but, in the judgment of those 
 who have perused Dr Reids writings with 
 an intelligent and candid attention, these 
 misrepresentations nmst recoil on their 
 authors ; while they who are really inter- 
 ested in the progress of useful science, will 
 be disposed rather to lend their aid in sup- 
 plying what is defective in his views than 
 to reject hastily a doctrine which aims, by 
 the developeraent of some logical principles 
 overlooked in the absurd systems which 
 have been borrowed from the schools, to vin- 
 dicate the authority of truths intimately and 
 extensively connected with human happiness. 
 
 In the prosecution of mj' own speculations 
 on the human mind, I shall have occasion 
 to explain myself fully concerning this, as 
 well as various other questions connected 
 with the foundations of jihilosophical evi- 
 dence. The new doctrines and new phrase- 
 ology on that subject, ^vhich have lately 
 become fashionable among some metaphy- 
 sicians in Germany, and which, in my 
 opinion, have contributed not a little to 
 involve it in additional obscurity, are a 
 sufficient proof that this essential and funda- 
 mental article of logic is not as yet com- 
 pletely exhausted. 
 
 In order to bring the foregoing remarks 
 within some compass, I have found it 
 necessary to confine myself to such objec- 
 tions as strike at the root of Dr Reid's 
 philosophy, without tcniching on any of his 
 opinions on particular topics, however im- 
 jiortant. I have been obliged also to com- 
 press what I have stated within narrower 
 limits than were perhaps consistent with 
 complete perspicuity ; and to reject many 
 illustrations which crowded upon me at 
 almost every step of my progress. 
 
 It may not, perhaps, be superfluous to 
 add, that, supposing some of these objections 
 to possess more force than I have ascribed 
 to them in my reply, it will ncjt therefore 
 follow, that little advantage is to be derived
 
 OF THOMAS REID, D.D. 
 
 29 
 
 from a careful [lerusa! uf the speculations 
 :i<^ainst which they are directeJ. Even they 
 who dissent the most widely from Dr Reid's 
 conclusions, can scarcely fail to admit, that, 
 as a writer, he exhibits a striking contrast 
 to the most successful of his predecessors, 
 ill a logical precision and simplicity of 
 laiiu:uaL!;e — his statement of facts being 
 neither vitiated by physiological hypothesis, 
 nor obscured by scholastic mystery. Who- 
 ever has reflected on the infinite importance, 
 in such inquiries, of a skilful use of words 
 as the essential instrument of tliought, 
 must be aware of the influence which his 
 works are likely to have on the future pro- 
 gress of science, were they to produce no 
 other effect than a general imitation of his 
 mode of reasoning, and of his guarded 
 phraseology. 
 
 It is not, indeed, every reader to whom 
 these inquiries are accessible ; for habits of 
 attention in general, and still more habits 
 of attention to the pl.ceiKimeuH of thought, 
 require early and careful cultivation ; but 
 tliose who are capable of the exertion will 
 soon recognise, in Dr Reid's statements, 
 the faithful history of their own minds, and 
 will find their labours amply rewarded by 
 that satisfaction which always accompanies 
 the diseovei'v of useful truth- They may 
 expect, also, to be rewarded by some intel- 
 lectual acquisitions not altogetlier useless in 
 their other studies. An author well quali- 
 fied to judge, from his own experience, of 
 wliatever conduces to invigorate or to em- 
 bellish the understanding, has beautifully 
 remarket'., that " by turning the soul inward 
 on itself, its forces are concentrated, and are 
 fitted for strony;er and bolder fiiglits of 
 science; and that, in such pursuits, wliether 
 we take, or whether we lose the game, tlie 
 chase is certainly of .'■ervice."* In this 
 respect, the jihilosophy of the mind (ab- 
 straftiiig entirely from that pre-eminence 
 which belongs to it in conse()iience of its 
 practical a]>plications) may claim a distin- 
 guish d rank among those preparatory dis- 
 ciplines which anotlier writer, of no less 
 emint ncc, has happily compared to " the 
 crojis which are raised, not for the sake of 
 the harvest, but to be ploughed in as a dress- 
 ing to the land."-}- 
 
 SFX'TION III. 
 
 CO.\CI.''S!ON Ol' THE NARRATIVE. 
 
 The three works to which the foregoing 
 remarks refer- together with the Essay on 
 Quantity, pubiishec] in the " Philosopiiical 
 
 * Preface to Mr Burk '« " liway on the Sublime 
 and Keaiiliful." 
 •f liirtuji Kerkeley'i " Querist." 
 
 Transactions of the Royal Society of Lon- 
 don," and a short but masterly Analysis 
 of Aristotle's Logic, which forms an ap- 
 pendix to the third volume of Lord Kames' 
 " Sketches'' — comprehend the whole of Dr 
 Reid's publications.* The interval between 
 the dates of the first and last of these amounts 
 to no less than forty years, although he had 
 attained to the age of thirty-eight before he 
 ventured to appear as an author. 
 
 With the " Essays on the Active Powers 
 of Man," he closed his literary career; but 
 he continued, notwithstanding, to prosecute 
 his studies with unabated ardour and activity. 
 The more modern improvements in chemis- 
 try attracted his particular notice ; and he 
 applied himself, with his wonted diligence 
 and success, to the study of its new doctrines 
 and new nomenclature. He amused him- 
 self also, at times, in preparing, for a philo- 
 sophical society of wliich he was a member, 
 short essays on particular topics which 
 happened to interest his curiosity, and on 
 which he thought he might derive useful 
 hints from friendly discussion. The most 
 important of these were — " An Examination 
 of Priestley's Opinions concerning Matter 
 and jMind;" "Observations on the 'Utopia' 
 of Sir Thomas More ;" and " Physiologi- 
 cal Refiections on Muscular Motion." This 
 last essay appears to have been written in 
 the eighty-sixth year of his age, and was 
 read liy the author to his associates, a few 
 months before his death. His "thoughts 
 were led to the speculations it contains," 
 (as he himself mentions in the conclusion,) 
 " by the experience of some of the efl'ects 
 which old age produces on the muscular 
 motions." '• As they were occasioned, 
 therefore," he adds, " by the infirmities of 
 age, they will, I hope, be heard with the 
 greater indulgence." 
 
 Among tiie various occupations with 
 which he thus enlivened his retiremeut, the 
 mathematical pursuits of his earlier years 
 held a distinguished ])lace. He aeliglited 
 to converse about them with his friends ; 
 and often exercised his skill in the investi- 
 gation of jiarticnlar jiroblenis. His know- 
 ledge of ancient geometry had not probably 
 b( en, at any time, very extensive ; but he 
 had cultivated diligeiitly those parts of 
 H:athematical science which are subservient 
 to the study of Sir Isaac Newton's works. 
 He had a predilection, more particularly, 
 for researches rc(iniring the aid of arith- 
 metical calculation, in the practice of whii h 
 he possessed nnconnnon expertness and 
 address. I think I ha\i; sometimes ob- 
 served in him a slight ami amiable vanity, 
 connected with this accomplishment. 
 
 * Reid's" History (if the L'n vrrsity of fil.i>gow," 
 
 was )ml)li>ticil, .liter lii» ile.itli, in tlio " Slilll^(H.ll 
 Account iif Sciill.iiul '' It is now, for tl.e (ir^t tiiue, 
 B(lcl(.d to liiK uiljtr woilv.s. — H.
 
 30 
 
 ACCOUNT OF THE LIFE AND WRITINGS 
 
 The revival, at this period, of Dr Reid's 
 first scientific propensity, has often recalled 
 to me a favourite remark of Mr Smith's 
 
 that of all the amusements of old age, 
 
 the most grateful and soothing is a renewal 
 of acquaintance with the favourite studies 
 and favourite authors of our youth ; a re- 
 mark which, in his own case, seemed to be 
 more particularly exempliKed, while he was 
 re-perusing, with the enthusiasm of a stu- 
 dent, the tragic poets of ancient Greece. 
 I heard him, at least, repeat the observa- 
 tion more than once, while Sophocles or 
 Euripides lay open on his table. 
 
 In the case of Dr Reid, other motives 
 perhaps conspired with the influence of the 
 agreeable associations to which Mr Smith 
 probably alluded. His attention was always 
 fixed on the state of his intellectual facul- 
 ties ; and for counteracting the effects of 
 time on these, mathematical studies seem 
 to be fitted in a peculiar degree. They are 
 fortunately, too, within the reach of many 
 individuals, after a decay of memory dis- 
 qualifies them for inquiries which involve 
 a multiplicity of details. Such detached 
 problems, more especially, as Dr Reid com- 
 monly selected for his considei'ation — pro- 
 blems where all the data are brought at once 
 under the eye, and where a connected train 
 of thinking is not to be carried on from 
 day to day — will be found, (as I have wit- 
 nessed with pleasure in several instances,) 
 by those who are capable of such a recrea- 
 tion, a valuable addition to the scanty re- 
 sources of a life protracted beyond the or- 
 dinary limit. 
 
 While he was thus enjoying an old age 
 happy in some respects beyond the usual 
 lot of humanity, his domestic comfort suf- 
 fered a deep and incurable wound by the 
 death of Mrs Reid. He had had the mis- 
 fortune, too, of surviving, for many years, 
 a numerous family of promising children ; 
 four of whom (two sons and two daughters) 
 died after they attained to maturity. One 
 daughter only was left to him when he lost 
 his wife ; and of her affectionate good offices 
 he could not always avail himself, in con- 
 sequence of the attentions which her own 
 husband's infirmities required. Of this 
 lady, who is still alive, (the widow of 
 Patrick Carmichael, M. D.,*) I shall have 
 occasion again to introduce the name, be- 
 fore I conclude this narrative. 
 
 * A learned and worthy physician, who, after a 
 long residence in Holland, where he p^acti^ed medi- 
 cine, retired to Glasgow. He was a younger son ol 
 Professor Ger.-chnm Carmichael, who publshefl, 
 about the year \~riO, an edition of Puffenriorff, De 
 Officio H minis et Civis, and who is iironounced by 
 Dr Hutcheson, " by far the liest cjimmentator on 
 that book." [Carmichael was HiHchesoirs imrne. 
 diate predecessor in the chair of M-ral Piiilosophy in 
 the University ot Glasgow, and may be regarded, 
 on good grounds, as the real founder of the Scottish 
 school ot philosophy. — H.] 
 
 A short extract from a letter addressed 
 to myself by Dr Reid, not many weeks 
 after his wife's death, will, I am persuaded, 
 be acceptable to many, as an interesting 
 relic of the writer. 
 
 " By the loss of my bosom friend, with 
 whom I lived fifty-two years, I am brought 
 into a kind of new world, at a time of life 
 when old habits are not easily forgot, or new 
 ones acquired. But every world is God's 
 world, and I am thankful for the comforts 
 he has left me. Mrs Carmichael has now 
 the care of two old deaf men, and does every 
 thing in her power to please them ; and 
 both are very sensible of her goodness. I 
 have more health than, at my time of life, 
 I had any reason to expect. I walk about ; 
 entertain myself with reading what I soon 
 forget ; can converse with one person, if he 
 articulates distinctly, and is within ten 
 inches of my left ear ; go to church, without 
 hearing one word of what is said. You 
 know I never had any pretensions to viva- 
 city, but I am still free from languor and 
 ennui. 
 
 " If you are weary of this detail, impute 
 it to the anxiety you express to know the 
 state of my health. I wish you may have 
 no more uneasiness at myage, — being yours 
 most affectionately." 
 
 About four years after this event, he 
 was prevailed on, by his friend and relation, 
 Dr Gregory, to pass a few weeks, during 
 the summer of 1796, at Edinburgh. He 
 was accompanied by .Mrs Carmichael, vvho 
 lived with him in Dr Gregory's house ; a 
 situation which united under the same roof, 
 every advantage of medical care, of tender 
 attachment, and of philosophical inter- 
 course. As Dr Gregory's professional e:'.- 
 gagements, however, necessarily interfered 
 much with his attentions to his guest, I 
 enjoyed more of Dr Reid's society than 
 might otherwise have fallen to my share. 
 I had the pleasure, accordingly, of spend- 
 ing some hours with him daily, and of 
 attending him in his walking excursions, 
 which frequently extended to the distance 
 of three or four miles. His faculties (ex- 
 cepting his memory, which was considerably 
 impaired) appeared as vigorous as ever ; 
 and, although his deafness prevented him 
 from taking any share in general conversa- 
 tion, he was still able to enjoy the company 
 of a friend. Mr Playfair and myself were 
 both witnesses of the acuteness which he 
 displayed on one occasion, in detecting a 
 mistake, by no means obvious, in a manu- 
 script of his kinsman, David Gregory, on the 
 subject of " Prime and Ultimate Ratios." 
 Nor had his temper suffered from the hand 
 of time, either in point of gentleness or of 
 gaiety. " Instead of repining at the en- 
 joyments of the young, he delighted in pro- 
 moting them ; and, after all the losses he
 
 OF THOMAS REID, D.D. 
 
 31 
 
 bad sustained in his own family, he con- 
 tinued to treat children with such conde- 
 scension and benignity, that some very 
 young ones noticed the peculiar kindness 
 of h s eye."* In apparent s-oundness and 
 activity of body, he resembled more a man 
 of sixty than of eighty-seven. 
 
 He returned to Glasgow in his usual 
 health and spirits ; and continued, for some 
 weeks, to devote, as formerly, a regular por- 
 tion of his time to the exercise both of body 
 and of mind. It appears, from a letter of 
 Dr Cleghorn's to Dr Gregory, that he was 
 still able to work with his own hands in his 
 garden ; and he was found by Dr Brow n, 
 occupied in the solution of an algebraical 
 problem of considerable difficulty, in which, 
 after the labour of a day or two, he at last 
 succeeded. It was in the course of the 
 same short interval, that he coiimiitted to 
 writing those particulars concerning his an- 
 cestors, which I have already mentioned. 
 
 This active and useful life was now, how- 
 ever, drawing to a conclusion. A violent 
 disorder attacked him about the end of 
 September ; but does not seem to have 
 occasioned much alarm to those about him, 
 till he was visited bv Dr Cleghorn, who 
 soon after comniunicated his apprehensions 
 in a letter to Dr Gregory. Anionir other 
 symptoms, he mentioned particularly "that 
 alteration of voice and features which, 
 though not easily described, is so well 
 known to all who have opportunities of 
 seeing life clo?e." Dr Reid's own opini(m 
 of Ills case was probably the same with that 
 of his physician ; as lie expressed to him on 
 his first visit his hope that he was "soon to 
 get his dismission." After a severe struggle, 
 iittcndcd with repeated strokes of palsy, he 
 ditd on the 7th of October following. Dr 
 Circgory had the melancholy satisfaction of 
 visiting his venerable friend on liis death- 
 Il-iI, and of jjaying him tliis ur.avaiiingmark 
 •if attachment before his powers of recol- 
 lection were entirely gone. 
 
 The only surviving descendant of Dr 
 R<-id is Mrs Carmichael, a daughter worthy 
 in every respect of such a father — long the 
 chief comfort and supj)ort of his old age, 
 and his anxious nurse in his last moments.t 
 
 Jn point of bodily constitution, few men 
 have been more indebted to nature than Dr 
 Reid. His form was vigorons and athletic ; 
 and his muscular force (though he was 
 somewhat under the middle size) uiiconi- 
 monly great; advantages to which his lialiits 
 of temperance and exercise, and the un- 
 clouded serenity of his temper, did ample 
 
 • I have hnrrdwcd tliis ^Piifc-urr frciin a just anil 
 elf'ttaiit cl.ar.icur ii( Dr Hciil, whirli :i|iiic.iriil, a few 
 clayn attiT lii^ dc aili, in one ol the (Jlasijow journals 
 1 had fMcisiori frcquenlly to vriilV the ttulli ol the 
 obscrvaiion during his vikit to Kduibiirgh. 
 
 i Note F. 
 
 justice. His countenance was strongly 
 expressive of deep and collected thought ; 
 but, when brightened up by the face of a 
 friend, what chiefly caught the attention 
 was a look of good-will and of kindness. A 
 picture of him, for which he consented, at 
 the particular request of Dr Gregory, to sit 
 to Mr Raeburn, during his last visit to 
 Edmburgh, is generally and justly ranked 
 among the happiest performances of that 
 excellent artist. The medallion of Tassie, 
 also, for which he sat in the eighty-first 
 year of liis age, presents a very perfect 
 resemblance. 
 
 I have little to add to what the foregoing 
 pages contain with respect to his character. 
 Its most pronuiient features were, intrepid 
 and inflexible rectitude, a pure and devoted 
 attachment to truth, and an enti.e crm- 
 maiid (acquired by the unwearied exertions 
 of a long life) over all his passions. Hence, 
 in those parts of his writings where his 
 subjectforces him to dispute the conclusions 
 of others, a scrupulous rejection of every 
 expression calculated to irritate those w horn 
 he was anxious to convince : and a spirit of 
 liberality and good-humour towards his 
 opponents, from w hich no asperity on their 
 part could provoke him for a moment to 
 deviate. The progress of useful know ledge, 
 more especially in what relates to human 
 nature and to human life, he believed to be 
 retarded rather than advanced by the in- 
 temperance of controversy ; and to be 
 secured most effectually wlien intrusted to 
 the slow but irresistible influence of sober 
 reasoiiing. That the argumentative talents 
 of the disjiutants might be improved by such 
 altercations, he was willing to allow ; but, 
 considered in their connection w ith the great 
 objects which all classes of writers piofess 
 equally to liave in view, he was ccnvinced 
 " that they have done more harm to the 
 practice, than they have done service to the 
 theory, of morality.' * 
 
 In private life, no man ever maintained, 
 more eminently or more miifoinily, the 
 dignity of jihilosophy ; combining with the 
 most amiable modesty and gentleness, the 
 noblest spiiit of indej)endci;ce. 'i'he only 
 jirel'ernients which he ever enjoyed he owed 
 to the unsolicited favour of the two learned 
 Ijodies who successively adopted him into 
 their number ; and the respectable rank 
 which he supported in society was the well- 
 eained reward of liis own academical la- 
 bours. The studies in which he deliglited 
 were little calculated to draw on him the 
 jiatronage of the great ; and he was un- 
 skilled in the art of courting advancement 
 bv " fashioning his doctrines to the varying 
 hour.'' 
 
 As a philosopl or, his genius was more 
 
 * Preface to !'■ [>c's " Tssay on Man."
 
 32 
 
 ACCOUNT OF THE LIFE AND WRITINGS 
 
 peculiarly characterised by a sound, cautious, 
 distinguishing judgment, by a singula r 
 jiatience and pcr.severance ol' thougiit, anil 
 by habits of the most fixed and concentrated 
 attention to his own mental operations ; 
 endowments wliicli, although not the most 
 splendid in the estimation of the multitude, 
 would seem entitled, from the history of 
 science, to rank among the rarest gifts of 
 the mind. 
 
 With these habits and powers, he united 
 (what does not always accompany them) 
 the curiosity of a naturalist, and the eye of 
 an observer ; and, accordingly, his inform- 
 ation about everything relating to physical 
 science, and to the useful arts, was exten- 
 sive and accurate. Ilis memory for his- 
 torical details was not so remarkable ; and 
 he used sometimes to regret the imperfect 
 decree in which he possessed this faculty. 
 I am inclined, however, to think, that, in 
 doing so, he underrated his natural advan- 
 tages ; estimating the strength of memory, 
 as men commonly do, rather by the recol- 
 lection of particular facts, than by the ])os- 
 sess on of those general conclusions, from a 
 subserviency to which such facts derive their 
 principal value. 
 
 Towards the close of life, indeed, his 
 memory was much less vigorous than the 
 other powers of his intellect ; in none of 
 which could I ever perceive any symptom 
 of decline. His ardour for knowledge, too, 
 remained unextinguished to the last ; and, 
 when cherished by the society of the young 
 and inquisitive, seemed even to increase 
 with his years. What is still more remark- 
 able, he retained, in extreme old age, all the 
 sympathetic tenderness and all the moral 
 sensibility of youth ; the liveliness of his 
 emotions, wherever the happiness of others 
 was concerned, forming an aft'ecting con- 
 trast to his own unconquerable firmness 
 under the severest trials. 
 
 Xor was the sensibility which he retained 
 the selfish and steriie offspring of taste and 
 indolence. It was alive and active, wher- 
 ever he could command the means of re- 
 lieving the distresses or of adding to the 
 comforts of others ; and was often felt in its 
 effects, where he was unseen and unknown. 
 Among the various proofs of this which 
 have happened to fall under my own know- 
 ledge, I cannot help mentioning ]jarticularly 
 (upon the most unquestionable authority) 
 the secrecy with which he conveyed his 
 occasional benefactions to his former parish- 
 ioners at New-.AIachar, long after his esta- 
 blishment at Glasgow. One donaticju, in 
 particular, during the scarcity of 17<''- — 
 a donation which, notwithstanding all liis 
 precautions, was distinctly traced to his 
 beneficence — mig'it perhaps have been 
 thought dispropoitionate to his limited in- 
 come, had not his own siujple and moderate 
 
 I habits multiplied the resources of his 
 
 I humanity. 
 
 His opinions on the most important sub- 
 jects are to be found in his works ; and that 
 s})irit of piety which animated every part 
 <jf his conduct forms the best comment on 
 their practical tendency. In the state in 
 which he lound the jihilosophical world, he 
 believed that his talents could not be so 
 usefully employed as in combating the 
 schemes of those who aimed at the com- 
 plete subversion of rel gion, both natural 
 and revealed ; convinced, with Dr Clarke, 
 that, " as Christianity pi'csupposes the 
 truth of Natural Religion, whatever tends 
 to discredit the latter must have a propor- 
 tionally greater effect in weakening the 
 authority of the former."^' In his views of 
 both, he seems to have coincided nearly 
 with Bishop Butler, an author whom he 
 held in tiie highest estimation. A very 
 careful abstract of the treatise entitled 
 " Analogy," drawn up by Dr Reid, many 
 years ago, for his own use, still exists 
 among his manuscripts ; and the short 
 " Dissertation on Vii tue" which Butler has 
 annexed to that work, together with the 
 " Discourses on Human Nature" published 
 in his volume of Sermons, he used always 
 to recommend as the most satisfactory ac- 
 count that has yet appeared of the funda- 
 mental principles of Morals : nor could he 
 conceal his regret, that the profound philo- 
 sophy which these Discourses contain 
 should of late have been so generally sup- 
 planted in England by the speculations of 
 some other moralists, who, while they pro- 
 fess to idolize the memory of Locke, 
 " approve little or nothing in his writings, 
 but his errors. "t 
 
 Deeply impressed, however, as he was 
 with his own principles, he possessed the 
 nnist perfect liberality towards all whom he 
 believed to be honestly and conscientiously 
 devoted to the search of truth. With one 
 very distinguished character, the late Lord 
 Kanies, he lived in the most cordial and 
 affectionate friendship, notwithstanding the 
 avowed ojipobition of their sentiments on 
 some moral questions to which he attached 
 the greatest importance. Both of them, 
 liowever, were the friends of virtue and of 
 mankind ; and both were able to temper the 
 warmth of free discussion with the for- 
 bearance and good humour founded on re- 
 ciprocal esteem. No two men, certainl}-, 
 ever exhibited a more striking contrast in 
 their conversation, or in their constitutional 
 tempers : — the one, slow and cautious in 
 
 * Cdllectimi of Papers which passed I'otwocn Leib- 
 liUz and Clarke. See Dr Clarke's Dedicatu ii. 
 
 f I liave adoDted here, the w.irds which Dr Cla'kc 
 applied to some of .Mr Locke 6 earlier follouers. 
 'I hey are slill more apijlicahk' tn iriany writers ol the 
 present times See Clarke's Frst Iteply to I-eilj- 
 nitz.
 
 OF THOMAS REID, D.D. 
 
 33 
 
 his decisions, even on those topics which 
 he had most diligently studied ; reserved 
 and silent in promiscuous society ; and re- 
 taining, after all his literary eminence, the 
 same simple and unassuming manners which 
 he brought from his country residence : 
 the other, lively, rapid, and communicative ; 
 accustomed, by his professional pursuits, 
 to wield with address the weapons of con- 
 troversy, and not averse to a trial of his 
 powers on questions the most foreign to his 
 ordinary habits of inquiry. But these cha- 
 racteristical differences, while to their com- 
 mon friends they lent an additional charm 
 to the distinguishing merits of each, served 
 only to enliven their social intercourse, and 
 to cement their mutual attachment. 
 
 I recollect few, if any anecdotes of Dr 
 Reid, which appear to me calculated to 
 throw additional light on his character ; 
 and I suspect strongly, that many of those 
 which are to be met with in biographical 
 publications are more likely to mislead 
 tiian to inform. A trifling incident, it is 
 true, may sometimes paint a peculiar fea- 
 ture better than the most elaborate descrip- 
 tion ; but a selection of incidents really 
 characteristical, presupposes, in the ob- 
 server, a rare capacity to discriminate and 
 to generalize ; and where this capacity is 
 wanting, a biographer, with the most scru- 
 pulous attention to the veracity of his de- 
 tails, may yet convey a very f.iise concep- 
 tion of tlie individual he would describe. 
 As, in the present instance, my subject 
 afforded no materials for such a choice, I 
 have attempted, to the best of my abilities, 
 (instead of retailing detached fragments of 
 conversations, or recording insulated and 
 unmeaning occurrences,) to communicate 
 to others the general impressions which Dr 
 Reid's character has left on my own mind. 
 In this attempt I am far from being confi- 
 dent that I have succeeded ; but, how barren 
 soever I may have thus rendered my pages 
 in the estimation of those who consider 
 biography merely in the liglit of an amusing 
 tale, 1 liave, at least, the satisfaction to 
 think, that my jiicture, though faint in the 
 colouring, does not present a distorted re- 
 semblance of the original. 
 
 The confidential correspondence of an 
 individual with his friends, affords to tlie 
 student of human nature, materials of far 
 greater authenticity and importance; more 
 particularly, tlie correspondence of a man 
 like Dr Reid, who will not be suspected by 
 those who knew hini, of accommodating his 
 letters (as has been alleged of Cicero) to 
 the liumo rs and ])rinci]iles of those whom 
 he aildn-ssfd. I am far, at the same time, 
 from tiiinUiig tliat tlie correspondence of 
 I)r Ki-id would be generally interLsting ; 
 (n- even that he excelled in this species of 
 writing : but few men, I sincerely believe, 
 
 who have written so much, have left be- 
 hind them such unblemished memorials of 
 their virtue. 
 
 At present, I shall only transcribe two 
 letters, which I select from a considerable 
 number now lying before me, as they seem 
 to accord, more than the others, with the 
 general design of this Memoir. The first 
 (which is dated January 13, 1779) is ad- 
 dressed to the Rev. William Gregory, 
 (now Rector of St Andrew's, Canterbury,) 
 then an undergraduate in Balliol College, 
 Oxford. It relates to a remarkable pecu- 
 liarity in Dr Reid's physical temperament, 
 connected with the subject of dreaming ; 
 and is farther interesting as a genuine re- 
 cord of some particulars in his early habits, 
 in which it is easy to perceive the openings 
 of a superior mind. 
 
 " The fact which your brother the Doctor 
 desires to be informed of, was as you men- 
 tion it. As far as I remember tlie circum- 
 stances, they Mere as follow : — 
 
 " About the age of fourteen, I was, almost 
 every night, unhappy in my sleep, from 
 frightful dreams : sometimes hanging over 
 a dreadful precipice, and just ready to drop 
 down ; sometimes pursued for my life, and 
 stopped by a wall, or by a sudden loss of 
 all strength ; sometimes ready to be de- 
 voured by a wild beast. How long I was 
 plagued with such dreams, I do not now 
 recollect. I believe it was for a year or 
 two at least ; and I think they had quite 
 left me before I was fifteen. In those days, 
 I was much given to what Mr Addison, in 
 one of his " Spectators," calls castle-build- 
 ing ; and, in my evening solitary walk, which 
 was generally all the exercise I took, my 
 thoughts would hurry me into some active 
 scene, where I generally acquitted myself 
 much to my own satisfaction ; and in these 
 scenes of imagination I performed many a 
 gallant exploit. At the same time, in my 
 dreams I found myself the most arrant 
 coward that ever was. Not only my cour- 
 age, but my strength failed nie in every 
 danger ; and I often rose from my bed in 
 the morning in such a panic that it took 
 some time to get the better of it. I wished 
 very much to get free of these uneasy 
 dreams, which not only made me unhappy 
 in sleep, but often left a disagreeable im- 
 pression in my mind for some part of the 
 following day. I thought it was worth 
 trying whether it was possible to recollect 
 that it was all a dream, and that 1 was in 
 no real danger. I often went to sleep with 
 my mind as strongly impressed as I could 
 with this thought, that I never in my life- 
 time was in any real danger, and that every 
 fright I had was a dream. After many 
 fruitless cndcavourH to recollect this when 
 the danger a]ipcared I efl'ected it at jst, 
 and htive often, when I was sliding over a 
 
 u
 
 34 
 
 ACCOUXT OF THE LIFE ANT) WRITINGS 
 
 precipice into the abyss, recollected tliat it 
 was all a dream, and boldly jumped down. 
 The effect of this commonly was, that I 
 immediately awoke. But I awoke calm 
 and intrepid, which I thought a great ac- 
 quisition. After this, my dreams were 
 never very uneasy ; and, in a short time, I 
 dreamed not at all. 
 
 " During all this time I was in perfect 
 health ; but whether my ceasing to dream 
 was the effect of the recollection above 
 mentioned, or of any change in the habit 
 of my body, which is usual about that 
 period of life, I cannot tell. I think it may 
 more probably be imputed to the last. 
 However, the fact was, that, for at least 
 forty years after, I dreamed none, to the 
 best of my remembrance ; and finding, from 
 the testimony of others, that this is some- 
 what uncommon, I have often, as soon as 
 I awoke, endeavoured to recollect, without 
 being able to recollect, anything that passed 
 in my sleep. For some years past, I can 
 sometimes recollect some kind of dreaming 
 thoughts, but so incoherent that I can 
 make nothing of them. 
 
 " The only distinct dream I ever had 
 eince I was about sixteen, as far as I 
 remember, was about two years ago. I 
 had got my head blistered for a fall. A 
 plaster, which was put upon it after the 
 blister, pained me excessively for a whole 
 night. In the morning I slept a little, and 
 dreamed, very distinctly, that I had fallen 
 into the hands of a party of Indians, and 
 was scaljied. 
 
 " I am apt to think that, as there is a 
 state of sleep, and a state wherein we are 
 awake, so there is an intermediate state, 
 which partakes of the other two. If a 
 man peremptorily resolves to rise at an 
 early hour for some interesting purpose, he 
 will of himself awake at that hour. A sick- 
 nurse gets the habit of sleeping in such a 
 manner that she hears the least whisper of 
 the sick person, and yet is refreshed by 
 this kind of half sleep. The same is the 
 case of a nurse who sleeps with a child in 
 her arms. I have slept on horseback, but 
 so as to preserve my balance ; and, if the 
 horse stumbled, I could make the exertion 
 necessary for saving me from a fall, as if I 
 was awake. 
 
 " I hope the sciences at your good uni- 
 versity are not in this state. Vet, from so 
 many learned men, so much at their ease, 
 one would expect something more than we 
 hear of." 
 
 For the other letter, T am indebted to 
 one of Dr Reid's most intimate friends, to 
 whom it was addressed, in the year 1784, 
 on occasion of the melancholy event to 
 which it alludes. 
 
 " I sympathize with you very ^ncerely 
 in the loss of a most amiable wife. I judge 
 
 of your feelings by the impression she made 
 upon my own heart, on a very short ac- 
 quaintance. But all the blessings of this 
 world are transient and uncertain ; and it 
 would be but a melancholy scene if there 
 were no prospect of another. 
 
 " I have often had occasion to admire 
 the resignation and fortitude of young per- 
 sons, even of the weaker sex, in the views 
 of death, when their imagination is filled 
 with all the gay prospects which the world 
 presents at that period. I have been wit- 
 ness to instances of this kind, which I 
 
 thought truly heroic, and I hear Mrs G 
 
 gave a remarkable one. 
 
 " To see the soul increase in vigour and 
 wisdom, and in every amiable quality, when 
 health, and strength, and animal spirits 
 decay — when it is to be torn by violence 
 from all that filled the imagination and 
 flattered hope — is a spectacle truly grand 
 and instructive to the surviving. To think 
 that the soul perishes in that fatal moment 
 when it is purified by this fiery trial, and 
 fitted for the noblest exertions in another 
 state, is an opinion which I cannot help 
 looking down upon with contempt and dis- 
 dain. 
 
 " In old people, there is no more merit in 
 leaving this world with perfect acquiescence 
 than in rising from a feast after one is full. 
 When I have before me the prospect of the 
 infirmities, the distresses, and the peevish- 
 ness of old age, and when I have already 
 received more than my share of the good 
 things of this life, it would be ridiculous 
 indeed to be anxious about prolonging it ; 
 but, when I was four-and-twenty, to have 
 had no anxiety for its continuance, would, 
 I think, have required a noble effort. Such 
 efforts in those that are called to make them 
 surely shall not lose their reward." 
 
 I have now finished all that the limits of 
 my plan permit me to offer here as a tribute 
 to the memory of this excellent person. In 
 the details which I have stated, both with 
 respect to his private life and his scientific 
 pursuits, I have dwelt chiefly on such cir- 
 cumstances as appeared to me most likely 
 to interest the readers of his works, by 
 illustrating his character as a man, and his 
 views as an author. Of his merits as an 
 instructor of youth, I have said but little ; 
 partly from a wish to avoid unnecessary 
 diffuseness, but chiefly from my anxiety to 
 enlarge on those still more important la- 
 bours of which he has bequeathed the fruits 
 to future ages. And yet, had he left no 
 such monument to perpetuate his name, 
 the fidelity and zeal with which he dis- 
 charged, during so long a period, the^bscure 
 but momentous duties of his official station 
 would, in the judgment of the wise and 
 good, have ranked him in the first order of
 
 OF THOMAS REID, D.D. 
 
 useful citizens. " Nee eniui is solus rei- 
 publicse prodest, qui candidates extrahit, et 
 tuetur reos, et de pace belloque censet ; sed 
 qui juventutera exhortatur ; qui, iu tanta 
 bonorum prteceptorum inopia, virtute in- 
 struit aninios ; qui, ad pecuniam luxuri- 
 axnque cursu ruentes prensat ac retrahit, et, 
 si nihil aliud, certe nioratur : in private, 
 publicum negotium agit."* 
 
 In concluding this memoir, I trust I 
 shall be pardoned, if, for once, I give way 
 to a personal feeling, while I express the 
 satisfaction with which I now close, finally, 
 my attempts as a biographer. Those which 
 I have already made, were imposed on me 
 by the irresistible calls of duty and attach- 
 ment ; and, feeble as they are, when com- 
 pared with the magnitude of subjects so 
 splendid and so various, xhey have en- 
 croached deeply on that small portion of 
 literary leisure which indispensable engage- 
 ments allow me to command. I cannot, 
 at the same time, be insensible to the grati- 
 fication of having endeavoured to associate, j 
 in some degree, my name with three of the ' 
 greatest which have adorned this age — I 
 
 • Seneca." De Tranquill. An." cap. 3. 
 
 happy, if, without deviatmg intentionally 
 from truth, I may have succeeded, however 
 imperfectly, in my wish to gratify at once 
 the curiosity of the public, and to soothe the 
 
 recollections of surviving friends. But I, 
 
 too, have designs and enterprises of my 
 own ; and the execution of these (which, 
 alas ! swell in magnitude, as the time for 
 their accomplishment hastens to a period) 
 claims, at length, an imdivided attention. 
 Yet I should not look back on the past 
 with regret, if I could indulge the hope, 
 that the facts which it has been my province 
 to record — by displaying those fair rewards 
 of extensive usefulness, and of permanent 
 fame, which talents and industry, when 
 worthily directed, cannot fail to secure — 
 may contribute, in one single instance, to 
 foster the proud and virtuous independence 
 of genius ; or, amidst the gloom of poverty 
 and solitude, to gild the distant prospect of 
 the unfriended scholar, whose laurels are 
 now slowly ripening in the unnoticed pri- 
 vacy of humble life." 
 
 * On Reid's doctrines Mr Stewart lias also some 
 valuable observations in his" Dissertation on the Pro- 
 gress of Metaphysical and Ethical Philosophy."— H. 
 
 NOTES.* 
 
 Note A. — Page 4. 
 
 In the account given in the text of Dr 
 Reid's ancestors, I have followed scrupu- 
 lously the information contained in his own 
 memorandums. I have some suspicion, 
 however, that he has committed a mistake 
 with respect to the name of the translator 
 of Buchanan's History ; which would ap- 
 pear, from the I\IS. in Glasgow College, to 
 have been, not Adam, but John. At the 
 same time, as tliis last statement rests on 
 an authority altogether unknown, (being 
 written in a hand different from the rest of 
 the MS.,t) there is a possibility that Dr 
 
 • If another edition of this Memoir should ever 
 be called t^r, 1 must request that the printer may 
 adhere to the plan which I mvself have thought 
 advifcable to adopt in the distribution of my notes. 
 A mistake which has brcn committed in a late edi- 
 tion of my Lite of Dr liobcrtson, where a long 
 Appendix is broken down \UU) foot.nolrs,\\\]] suf- 
 ficiently account for this request to those who have 
 teen that pulilicaiion. 
 
 t It ifl to the following purport :— "'I'he Historic 
 of .Scotland, liist written in the Latin tungue by 
 that lamouH and learned man, George Kuchanan, 
 and afterwards translated in'o the Scottishe tungue 
 by John Head, Ksquyar, brottif-r to James Head, 
 person of IJaiichory. Jernaii, whyle he lived, 'i'liey 
 both ly inttred in the parish cliurch of that towne, 
 »catcd not farre from the banke of the river of Dee, 
 e.^peciirg the general ronurrectioii, and the glorious 
 appearing of Jesus ( hriHt, there Kcdimer." 1 he date 
 
 Reid's account may be correct ; and, there- 
 fore, I have thought it advisable, in a matter 
 of so very trifling consequence, to adhere to 
 it in preference to the other. 
 
 The following particulars with respect to 
 Tliomas Reid may, perhaps, be acceptable 
 to some of my readers. They are copied 
 from Dempster, a contemporary writer ; 
 whose details concerning his countrymen, it 
 must, however, be confessed, are not always 
 to be implicitly relied on : — 
 
 " Thomas lieidus, Aberdonensis, pueri- 
 ti;B raeaj et infantilis otii sub Thoma Car- 
 gillo coUega, Lovaniiliterasinschola Lipsii* 
 ^e^io didicit, quas magno nomine in Ger- 
 niania docuit, earns Principibus. Londini 
 diu in comitatu humanissimi ac claris.=.imi 
 viri, Fulconis Grevilli, Regit Consiliarii 
 luterioris et Anglite Proqusestoris, egit : 
 tutn ad amicitiam Regis, eodem Fulcone 
 deducente, evectus, inter Palatiiios adinis- 
 
 of the transcript is 12th December Ifi.ii. Accord- 
 ing to Calderwood'i MS. History of the Church of 
 .Scotland, John Head was •' servitor and writer to 
 Mr George Huchanan." But this is not likely. — H. 
 • 'Miis is doutjtiul ; for Sir Kobert Ayloun, in the 
 account he gives of Ileid's studies, makes no mention 
 of .so remarkable a cirriimslaticc. Dempster possibly 
 confuted J'homas Keid with Keid's friend,. Sir 'I'homsi 
 Seghet, another learned and witndeiiiig Scolchm;in, 
 .ind a favourite pupil ot " tlic riiiice of Latin Let. 
 ters.'— M. 
 
 D 2
 
 36 
 
 ACCOUNT OF THE LIFE AND WRITINGS 
 
 Busj a literis Latinis Regi fuit. Scripsit 
 multa, ut est maf^na indole et varia erudi- 
 tione," &c. " Ex aula se, nemine conscio, 
 nuper proripuit, dum illi omnia festinati 
 honoris augmenta singuli ominarentur, nee 
 quid deinde egerit aut quo locorum se con- 
 tulerit quisquam indieare potuit. Multi 
 suspicabantur, tiudio aulse affectum, nion- 
 asticEe quieti seipsum tradidisse, sub an- 
 num 1618. Rumor postea fuit in aulam 
 rediise, et meritissimis honoribus redditum, 
 sed nunquam id ccnsequetur quod virtus 
 promeretur." — Hist. Ecclesiaslica Genlis 
 Scofornm, lib. xvi. p. 57G. 
 
 What was the judgment of Thomas 
 Reid's own times with respect to his genius, 
 and what their hopes of his posthumous 
 fame, may be collected from an elegy on 
 his death by his learned countryman [Sir] 
 Robert Aytoun. Already, before the lapse 
 of two hundred years, some apology, alas ! 
 may be thought necessary for an attempt to 
 rescue his name from total oblivion. 
 
 Aytoun's elegy on Reid is referred to in 
 terms very flattermg both to its author and 
 to its subject, by the editor of the collec- 
 tion entitled, " Poetarum Scotorum Musne 
 Sacrse."* " Tn obitum Thonite Rheidi 
 [Rhaedi] epicedium extat elegantissimum 
 Roberti Aytoni, viri literis ac dignitate 
 clarissimi, in Delitiis Poetarum Scotorum, 
 ubi et ipsius quoque poemata, paucula qui- 
 dem ilia, sed venusta, sed elegantia, corn- 
 parent."! 
 
 * The well-known William Lauder. — H. 
 
 + I add the following hrief notices, which I chance 
 to have, in regard to this elegant scholar and acute 
 philosopher. From Sir Robert Avtoun's Elegy, 
 it appears, that, after finishing his studies in Scot, 
 land, Reid proceeded to France. There, however, 
 he did no; tarry ; for, as Scottish'pliilosophers.were 
 then in high academical repute, he soon received a 
 call to Germany : — 
 
 " attraxit Germania philtro 
 
 Et precis et pretii." 
 
 In that country, he taught philosophy and humane 
 letters for several years witli distinguished reputation, 
 in the universities of Leipsic and Rostoch. 
 
 " Palladis in castris multa hie cum laude merentem, 
 Et victa de Barbaric sciolisque sophistis 
 Ducentem insignes fama victrice triumphos 
 I.ipsia detinuit lon;.um. yuis credidit illic 
 Se rite admissum in Phoebi sacraria, Rhaedo 
 Non pandente fores ? Quis per dumeta I.ycsi 
 Ausus iter tentare, nisi duce et auspice Rhsdo ? 
 
 Nee tibi fama minor qua Balthica liltora special 
 Roslochiiim, paucis istic tibi plurimus annis 
 Crevit bono-, nullo non admirante prolundas 
 Doctrinae aggestos tot in uno peotore accrvos, 
 Felicemque viam fandi, quocunque liberet 
 Ore loqui, quocunque habitu producere partus 
 Mentis, et exanimes scriptis aiiimare papyros." 
 
 While in Germany, he wrote the following treat- 
 ises, which display great jibilrisophical talent: — 
 "Thorns Rhajdi, .Srnti, Oe (Hijccto Metaphysira; 
 Dissenatio contra Hcniiingum Arnii-seura. Ros. 
 tochi: : Ifil'i. • 4to 
 
 " '1 hnmfe RhEpdi, Scoti, Pervigilia Mctaphysira 
 desideratissima. Rostocbii : 1613." 4lo. 
 
 I have likewise seen referred to, a System of Logic 
 bv him, published at Rostoch; but in what year I 
 know not. 'I'hough the date of the earliest of the 
 preceding ttea'isesbe ItilS, it appears tliat he was 
 at Rostoch tielore 1(511, and that he then had pul)- 
 
 The only works of Alexander Reid of 
 which I have heard are "Chirurgical Lec- 
 tures on Tumors and Ulcers," London, 
 l(i:55; and a "Treatise of the First Fart 
 of Chirurgerie," London, 1638. Reappears 
 to have been the physician and friend of 
 the celebrated mathematician Thomas 
 Harriot, of whose interesting history so 
 little was known till the recent discovery of 
 his manuscripts by Mr Zach of Saxe-Gotiia. 
 
 A remarkable instance of the careless or 
 capricious orthography formerly so common 
 in writing proper names, occurs in the dif- 
 ferent individuals to whom this note refers. 
 Sometimes the family name is written — 
 Reid ; on other occasions, Riede, Read, 
 Rhead, or Rhaid. 
 
 Note B. — Page 4. 
 
 Dr Turnbull's work on moral philosophy 
 was published at London in 1740. As I 
 have only turned over a few pages, I can- 
 not say anytliing with respect to its merits. 
 The mottoes on the title-page are curious, 
 when considered in connection with those 
 inquiries which his pupil afterwards prose- 
 cuted with so nmch success ; and may, 
 perhaps, without his perceiving it, have had 
 some effect in suggesting to him that plan 
 of philosophizing which he so systemati- 
 cally and so happily pursued : — 
 
 " If natural philosophy, in all its parts, 
 
 lished a dissertation against ArnisEBUs; to which 
 this philosopher in that year replied in his '' Vindi- 
 cife secundum veritatem pro Aristotele et.sanioribus 
 quibusque philosophis contra ThomjE Rhjedi, Scoti, 
 Dissertationem elenchticam de subjecto Metaphysices 
 et naturaEntis, assertasab Heuningo Arnisaeo, Hal. 
 berstadiensi. Francofurti : 1611." 4to. 
 
 At what date Reid returned to England, or when 
 he was appointed Latin Secretary to King James, 
 does not appear. 1 find, however, from Smith's 
 Life of Patrick Young, who was associated with 
 him in the translation into Latin of James's English 
 works, and who succeeded him as Secretary, that 
 Reid died in 16-24. There is also to be found in the 
 same Life (sec " Vilse quoriindam eruditissimonim 
 virorum," kc.) the fragment of a Dissertation by 
 Reid — " Quod Hegibus et Licitum tt Pecorum sit 
 Scriliere." A consiiierable number of Reid's poems 
 are to be found in the " Delitise Poetarum Scoto- 
 rum ;" and his paraphrase of the KUth Psalm, 
 which is not among these, was published during his 
 life, with high encomium, by William Barclay in hia 
 " Juilicium de Poetico duello Eglisemmii." The 
 writings which he left were, huwever, only occa- 
 sional and fe:gitive pieces — only indications of what 
 he would have accompli.-hed bad an early death not 
 frustrated his great designs. 
 
 " Et tu Rhjede jaces opera inter manca, minasque 
 Scriptoriim ingeiites, quels si supremafnisset 
 Cum lima porrccta manus, ron ulla fuisset 
 Calliopes toto Sophiseve illustrior albo 
 Quam qiiEe RliEedeum praelerret pagina notnen. 
 
 Nunc ceu rapta tuis suprrant tantummodo bustis 
 Paucula furtivas schcdiasmata fusa per boras, 
 Qiialiacunque tamen siuit hsec, haic ipsa revincent 
 Esse Caledoniis etiamnum lumen aUimnis 
 Et genium, quo vel Scoti Subtilis acumen, 
 Vet poterunt dulces Buchanan! iequare Camoenas." 
 
 Mr S'ewart (p 3) is misinformed in stating th.at 
 Reid published any collection of bis Dissertations. — 
 H.
 
 OF THOMAS REID, D.D. 
 
 37 
 
 by pursuing this method, shall, at length, 
 be perfected, the bounds of moral philoso- 
 pliy will also be enlarged." 
 
 N't-wtnji^s Optics, 
 
 " Account for moral as for natural things." 
 
 Pope. 
 
 For the opinion of a very competent 
 judge, with respect to the merits of the 
 " Treatise on Ancient Painting," vide 
 Hogarth's Print, entitled "Beer-Lane." 
 
 Note C Page 10. 
 
 " Dr Moor combined," &c. — James 
 Moor, LL.D., author of a very ingenious 
 fragment on Greek grammar, and of other 
 philological essays. He was also distin- 
 guished by a profound acquaintance with 
 ancient geometry. Dr Simson, an excel- 
 lent judge of his merits, both in literature 
 and science, has somewhere honoured him 
 with the following encomium : — " Tum in 
 Mathesi, tum in Grsecis Literis multum et 
 feliciter versatus." 
 
 " The Wilsons," (both father and son,) 
 
 &c Alexander Wilson, M.D., and 
 
 Patrick Wilson, Esq., well known over 
 Europe by their " Oljservations on the 
 Solar Spots," and many other valuable 
 memoirs. 
 
 Note D.— Page 20. 
 
 A writer of great talents (after having 
 reproached Dr Reid with "a gross igno- 
 rance, disgraceful to the university of which 
 he was a member") boasts of the trifling 
 expense of time and thought which it had 
 cost himself to overturn his philosophy. 
 " Dr Oswald is pleased to pay me a com- 
 pliment in saying, that ' I might employ 
 myself to more advantage to the i)ul)lic, by 
 jnirsiiing other branches of science, than by 
 (iei iding rashly on a subject which he sees 
 I have not studied.' In return to tliis 
 compliment, I shall not affront him, by 
 telling him how very little of my time this 
 business has hitherto taken up. If he 
 alludes to my experiments, I can assure 
 him that I have lost no time at all ; for, 
 having been intent upon such as require 
 the use of a burning lens, I believe I have 
 not lost one hour of sunshine on this 
 account And the public may, perhaps, be 
 informe<l, some time or other, of what I 
 have been doing in the sun, as well as in 
 the xhritley — [Priestley's] " I'^xamination 
 of lleid's Inquiry," &,c., p. W'tT. See also 
 pp. Kll, 102 of the same work. 
 
 Note E.— Page 27- 
 
 The following strictures on Dr Priestley's 
 " Examination," &c., are copied from a 
 very judicious note in Dr Campbell's " Phi- 
 losopliy of Rhetoric," vol i. p. 3. 
 
 " I shall only subjoin two remarks 
 
 on this book. The first is, that the author, 
 through the whole, confounds two things 
 totally distinct — certain associations of ideas, 
 and certain judgments implying belief, which, 
 though in .so?;;?, are not in all cases, and, 
 therefore not npcrssarilj connected with 
 association. And if so, merely to account 
 for the association is in no case to account 
 for the belief with which it is attended. 
 JSay, admitting his plea, (p. 86,) that, by 
 the principle of association, not only the 
 ideas, but the concomitant belief may be 
 accounted for, even this does not invalidate 
 the doctrine he impugns ; for, let it be 
 observed, that it is one thing to assign a 
 cause, which, from the mechanism of our 
 nature, has given rise to a particular tenet 
 of belief, and another thing to produce a 
 reason by which the understanding has 
 been convinced. Now, unless this be done 
 as to the principles in question, they must 
 be considered as primary truths in respect 
 of the understanding, which never deduced 
 them from other truths, and which is under 
 a necessity, in all her moral reasonings, of 
 founding upon them. In fact, to give any 
 other account of our conviction of them, is 
 to confirm, instead of confuting the doctrine, 
 that, in all argumentation, they must be 
 regarded as primary truths, or truths which 
 reason never inferred through any medium, 
 from other truths previously perceived. 
 My second remark is, that, though this exa- 
 miner has, from Dr Reid, given us a cata- 
 logue of first principles, which he deems 
 miworthy of the honourable place assigned 
 them, he has nowhere thought proper to 
 give us a list of those self-evident truths 
 which, by his own account, and in his own 
 express words, ' must be assumed as the 
 foundation of all our reasoning.' How 
 much light might have been thrown upon 
 the subject by the contrast ! Perhaps we 
 should have been enabled, on the compari- 
 son, to discover some distinctive characters 
 in his genuine axioms, which would have 
 preserved us from the danger of confound- 
 ing them with their spurious ones. No- 
 thing is more evident than that, in whatever 
 regards matter of fact, the mathematical 
 axioms will not answer. These are purely 
 fitted for evolving tlic abstract rehttions of 
 quantity. 'I'liis he in effect owns himself, 
 (p. 'M).) It wonlil have been obliging, then, 
 anil would have greatly contributed to 
 shorten the controv<?rsy, if he had given us, 
 at least, a specimen of those self-evident
 
 8H ACCOUNT OF THE LIFK AND WlUriNGS OF Dll REID. 
 
 princip'es wliieh, in his estimation, are the 
 nan plus ultia of moral reasoning." 
 
 NoTK F — Page 31. 
 
 Dr Reid's father, the Rev. Lewis Reid, 
 married, for his second wife, Janet, daughter 
 of Mr Fraser of Phopachy, in the county 
 of Inverness, A daughter of this marriage 
 is still alive ; the wife of the Rev. Alex- 
 ander Leslie, and tlie mother of the Rev. 
 James Leslie, ministers of Fordoun. To 
 the latter of these gentlemen, I am indebted 
 for the greater part of the information I 
 have been able to collect with respect to Dr 
 Reid, previous to his removal to Glasgow — 
 Mr Leslie's regard for the memory of his 
 uncle having prompted him, not only to 
 transmit to me such particulars as had 
 fallen under his own knowledge, but some 
 valuable letters on the same subject, which 
 he procured from his relations and friends 
 in the north. 
 
 For all the members of this most respect- 
 able family, Dr Reid entertained the 
 strongest sentiments of affection and regard. 
 During several years before his death, a 
 daughter of Mrs Leslie's was a constant 
 inmate of his house, and added much to the 
 happiness of his small domestic circle. 
 
 Another daughter of Mr Lewis Reid was 
 married to the Reverend John Rose, min- 
 ister of Udny. She died in 1793. — In 
 this connection Dr Reid was no less fortu- 
 nate than in the former ; and to Mr Rose 
 I am indebted for favours of the same kind 
 wth those which I have already acknow- 
 ledged from Mr Leslie. 
 
 The widow of Mr Lewis Reid died in 
 1 708, in the eighty-seventh year of her age ; 
 having survived her step-son, Dr Reid, 
 more than a year. 
 
 The limits within which I was obliged to 
 confine my biographical details, prevented 
 me from availing myself of many interest- 
 ing circumstances which were communi- 
 cated to me through the authentic channels 
 which I have now mentioned. But I can- 
 not omit this opportunity of returning to 
 my different correspondents, my warmest 
 acknowledgments for the pleasure and 
 instruction which I received from their 
 letters. 
 
 Mr Jardine, also, the learned Professor 
 of Logic in the University of Glasgow— a 
 gentleman who, for many years, Uved in 
 habits of the most confidential intimacy 
 with Dr Reid and his family — is entitled to 
 my best thanks for his obliging attention to 
 various queries which I took the liberty to 
 propose to him, concerning the history of 
 our common friend.* 
 
 • The preceding sheets were set before 1 was 
 favoured with the following interesting notices in snp- 
 
 plement of Mr Slewnrl's account ot Reid's Lite, b» 
 Dr Knight, Professor uf Natural Philosophy m 
 Maritchal C'ollekte, Atiordten ; and, in consequence, 
 it has been found imvo-sib.eto distribute thein in the 
 proper places — H. 
 
 P. 3. It is probable that 'I'homas Reid had been 
 educated.it Marischal CollcRe, where the teaching of 
 classes commenced iinincdiately on its Ibundatio in 
 159 i. In Wood's ' ha^ti Oxon.' (ttii.u or I'liss'a 
 edition, I. 394,) is the follnwing entry : — 
 
 " I6i0, May 28, Th.imas Keid, (Hhsdus,) M.A. 
 of Aberdeiie in Scotland, Incorporated. He had 
 before been a student of this Umversitie, and pub. 
 lished this year ' Paraphrasis Psalmi civ.' London : 
 IH-io 8vo. And about the same time,' Epist. ad 
 Episcopum Rofleiisem,' inSvo." 
 
 Both Secretary Reid and his brother Alexander, 
 the physician, seem to have died in rather early life 
 from some expressions in their wills. 
 
 Secretary Reid's transcript of King James VI's. 
 " Treatise on the Kevelatioiis," is preserved in 
 Marischal College library. It is uiterleavcd, has the 
 royal arms on the cover, and on the margins several 
 alterations in the well known hand.writing of thitt 
 monarch. 
 
 In his will, dated 19th May i6ii, he designs him- 
 self" Secretary to his Majesty for the Latin Tongue." 
 In Devon's '-Issues of the Exchequer, being pay. 
 ments made in the reign of James I., from the origi- 
 nal Records in the ancient Poll otfice," (published 
 18 (G,) is the following entry : — 
 
 '' To 'I homas Reed, Gentleman, the sum of 
 £,•26 : 9 : 4, in reward for the travail, .charges, and 
 expenses of himself and otners, employed ui writing 
 and lianslating the book of his Majesty's w 'rks out 
 of English into Latin, by his Majesty's special com 
 mandment, and for other his Highness's services, in 
 the month of October 1(317," Ike. 
 
 The original catalogue ol his library, which he be- 
 queathed to Marischal College, " fi>r the love I bear 
 to the town of New Aberdeen, and wishing the new 
 college and schools thereof should flouri^h," is still 
 extant amongst the town's records. He had pur. 
 chased in Ins travels some of the best editions of the 
 classics and commentators upon them, which were 
 then to be obtained. 
 
 His brother Alexander, M.D , (.Stewart, p. 4,) died 
 in London about ItiJl-. In 1630, he intimated to the 
 magistrates of Aberdeen his having bequeathed his 
 books a;'d MSS., and funds for bursaries to the col. 
 lege; and, in a letter to them, (4th Oct 1(133, ) he 
 trans'mitted £110 sterling for the latter pur|iose. 
 
 From a paper, dated in 1736, in Dr Thomas Reid's 
 hand-writing, it appears that he had an intention nf 
 being served heir to his direct progenitor, Robert, the 
 brother and heir of Secretary Reid in i6^4, in order 
 to enable h'm to insti' ute a suit with the mat;i.strates 
 of Aberdeen, about their management ot the fund 
 left bv his ancestor for the librarian's salary, which 
 fund had been greatly ddapidatcd by them since 
 1677. I'his was, however, rendered unnccess.iry by 
 a decision of the Court of Session, which deprived 
 them of the patronage ot that office, and restored it to 
 the persons in whom the Secretary's will had vested 
 it. 
 
 Dr Reid appears from the College records, to have 
 been in Dr (i. Turnbull's class, (as Mr Stewart men. 
 tions p. 4,) studying under him three sessions, and 
 becoming A. M in 17i6. He entered college in H^-i, 
 and was in the first fireek class taught by Dt Thomas 
 Blackwell, afterwards Principal, and celebrated, at 
 the time, for his strenuous attempts to revive the 
 study of the Greek language in the northern parts of 
 Scotland. 
 
 Dr lieid had entered in'o this plan with enthu- 
 siasm ; for his pupil and colleague, the late Professor 
 William Ogilvie, used to relate that he had heard 
 him recite to his class, demonstrations of Euclid in 
 the original language 
 
 The sermon which was preached by Mr John Bis- 
 set, on the day of moderating a call for Dr Reid, (to 
 the parish of New-Machar, near Aberdeen,) p. 5, 
 attracted much attention, and continued to be long a 
 favourite with the opponents of patronage. 
 
 P. 6. Immediately on Dr Reid's appointment to 
 the place of one of the Regents of King's College, he 
 prevailed on his colleagues to make great improve- 
 ments in their system of University education. Tlie 
 session was extended from five to seven months.
 
 [ 39 ] 
 
 CORRESPONDENCE OF DR REID. 
 
 The follow-ing correspondence consists of three consecutive series. 
 
 The /'•«/, for which I am indebted to my friend, Alexander Thomson, Esq., of Ban- 
 chory, extends from 1764 to 1770, and contains letters by Reid, during the first six years 
 after his removal to Glasgow, to Dr Andrew Skene, and his son, Dr David Skene, 
 physicians in Aberdeen. This correspondence was terminated, by the death of the father, 
 in 1767, and of the son, in 1771- Both were highly eminent in their profession; 
 but the latter, who hardly reached the age of forty, was one of the most zealous culti- 
 vators of the natural sciences in Scotland, and the valued correspondent of Linnaeus, 
 Pennant, Lord Kames, and other distinguished contemporaries. These letters afford 
 what was perhaps wanting to Mr Stewart's portraiture of Reid — they shew us the philo. 
 sopher in all the unaffected simplicity of his character, and as he appeared to his friends 
 in the familiar intercourse of ordinary life. 
 
 The second series comprises the letters addressed to Lord Kames, as given in Lord 
 Woodhouselee's Memoirs of the Life and Writings of that ingeuious philosopher. They 
 extend from 1772 to 1782, and are chiefly of scientific interest. 
 
 The third series contains a selection from Reid's letters to his kinsman, the late Dr 
 James Gregory, Professor of the Practice of Medicine in the University of Edinburgh. 
 Dr Gregory is known, not only as a distinguished physician, but as one of the most 
 elegant scholars and vigorous thinkers of his time. He was indeed a remai-kable member 
 even of a family in which, for two centuries, talent would almost seem to have been 
 entailed. To Dr Gregory and Mr Dugald Stewart, Reid appropriately dedicated his prin- 
 cipal work — the " Essays on the Intellectual Powers." The correspondence, which is of 
 varied interest, extends from 1783, and was only terminated by Reid's death in 1796. 
 
 I owe my best thanks to John Gregory, Esq., for the flattering manner in which he 
 placed these valuable letters at my disposal ; but my friend Dr Alison is not the only 
 other member of the family for whose kindness I have also to express my obligation — H. 
 
 A.— LETTERS TO DRS ANDREW AND DAVID SKENE. 
 
 I. 
 
 TO DR ANDREW SKENE. 
 
 Glasgow, Nov. 1 4th, 1764. 
 Dear Sir, — I have been for a long time 
 wishing for as much leisure as to write 
 you, if it was only to revive the memory 
 of the many happy hours which I have 
 enjoyed in your company, when, tete-a- 
 tete, we sat down to speak freely of men 
 and things, without reserve and without 
 malignity. The time slipt away so smootlily. 
 
 humanity clasriwas added, on a higher scale than had 
 been taiiMht pri-viously ; and the teaching of the tie. 
 ments of Latin, by the Profensor of Humanity, dis. 
 cotiiinued ; eoiiic of the fimall bursaries were united ; 
 mid an account of these alterations was given to tlie 
 I'Ublic ill a -mall tract, puhlislied in nm Dr Heid 
 Wrts in favour of one prolcusor tcachinR Ihe wliolc, or 
 the greater part of the curriculum, and ilierefore did 
 nr t follow the i)lan of eonfminf,' the professors to 
 W-paratc I rnn< hes, as hnd been <lnne in f;lav).'Ow since 
 l"v!7, an<l in M.irisclial ( ollegcnince I'M 'Hie plan 
 of a teven inontlik' ktssion, allir a trial of five yearf, 
 Kai abaniloneil. 
 
 that I could often have wished to have 
 dipt its wings. I dare not now be guilty 
 of any such agreeable irregularities ; for I 
 must launch forth in the morning, so as to 
 be at the College (which is a walk of eight 
 minutes) half an hour after seven, when I 
 speak for an hour, without interruption, to 
 an audience of about a Iniiidred. At eleven 
 I examine for an hour upon my morning 
 prelection ; but my audience is little more 
 than a third part of what it was in the 
 morning. In a week or two, I must, for 
 three days in the week, have a second pre- 
 lection at twelve, ui)on a dif1"rveiit subject, 
 where my audience will be niado up of those 
 who hear me in the morning, but do not 
 attend at eleven. IMy hearers commonly 
 attend my class two years at least. The 
 first session they attend the morning i)re- 
 Icction, and the hour of examination at 
 cleveti ; flie second and subs'iqucnt years 
 they attend llie two jircloctions, but not the 
 hour of examination, 'i'liey pay fees for 
 I the first two years, and tlien tliey are livc^
 
 40 
 
 CORRESPONDENCE OF DR RE ID. 
 
 of that class, and may attend gratis as many 
 years as they please. Many attend the 
 Moral Philosophy class four or five years ; 
 so that I have many preachers and students 
 of divinity and law of considerahle stand- 
 ing, before whom I stand in awe to speak 
 without more preparation than I have 
 leisure for. I have a great inclination to 
 attend some of the professors here — several 
 of whom are very eminent in their way ; 
 but I cannot find leisure. Much time is 
 consumed in our college meetings about 
 business, of which we have commonly four 
 or five in the weelc. We have a literary 
 society once a-week, consisting of the 
 Masters and two or three more ; where 
 each of the members has a discourse once 
 in the session. The Professors of Hu- 
 manity, Greek, Logic, and Natural Philo- 
 sophy, have as many hours as I have, some 
 of them more. All tlie other professors, 
 except one, teach at least one hour a-day ; 
 and vve are no less than fourteen in num- 
 ber. The hours of the different professors 
 are different so far as can be, that the same 
 student may attend two or three, or per- 
 haps more, at the same time. Near a third 
 part of our students are Irish. Thirty 
 came over lately in one ship, besides three 
 that went to Edinburgh. We have a good 
 many English, and some foreigners. Many 
 of the Irish, as well as Scotch, are poor, 
 and come up late, to save money ; so that 
 we are not yet fully conveened, although I 
 have been teaching ever since the 10th of 
 October. Those who pretend to know, 
 say that the number of students this 
 year, when fully conveened, will amount 
 to .300. 
 
 The Masters live in good habits with one 
 another, and manage their political differ- 
 ences with outward decency and good man- 
 ners, although with a good deal of intrigue 
 and secret caballing when there is an elec- 
 tion. I have met with perfect civility from 
 them all. By this time, I am sure you have 
 enough of tlie College; for you know as much 
 as I can tell you of the fine houses of the 
 Masters, of the Astronomical Observatory, 
 of Robin Fowlis' collection of pictures and 
 painting college, of the foundery for types 
 and printing house ; therefore, I will carry 
 you home to my own house, which lyes 
 among the middle of the weavers, like the 
 Back Wynd in Aberdeen. You go through 
 a long, dark, abominably nasty entry, which 
 leads you into a clean little close You walk 
 up stairs to a neat little dining-room, and 
 find as many other little rooms as just 
 accommodate my family so scantily that my 
 apartment Ls a closet of six feet by eight or 
 nine off the dining-room. To balance these 
 little inconveniences, the house is new and 
 fiee of buggs ; it has the best air and the 
 finest [irospect in Glasgow ; the privilege of 
 
 a large garden, very airy, to walk in, which 
 is not so nicely kept but one may use free- 
 dom with it. A five minutes' walk leads us 
 up a rocky precipice into a large park, partly 
 planted with firs and partly open, which 
 overlooks the town and all the country 
 round, and gives a view of the windings of 
 the Clyde for a great way. The ancient 
 cathedral stands at the foot of the rock, 
 half of its height below you, and half above 
 you ; and, indeed, it is a very magnificent 
 pile. 
 
 When we came here, the street we live 
 in (which is called the Drygate) was infested 
 with the smallpox, which were very mortaL 
 Two families in our neighbourhood lost all 
 their children, being three each. Little 
 David was seized with the infection, and 
 had a very great eruption both in his face 
 and over his whole body, which you will 
 believe would discompose his mother. . 
 
 Although my salary here be much the 
 same as at Aberdeen, yet, if the class does 
 not fall off, nor my health, so as to disable me 
 from teaching, I believe I shall be able to 
 live as easily as at Aberdeen, notwithstand- 
 ing the difference of the expense of Uving 
 at the two places. I have touched about 
 £70 of fees, and may possibly make out the 
 hundred this session. 
 
 And now, sir, after I have given you so 
 full an account of my own state, spiritual 
 and temporal, how goes it with you ? Are 
 George and Molly minding their business ? 
 I know Kate will mind hers. Is Dr David 
 littering up your house more and more with 
 all the birds of the air, the beasts of the 
 field, and the clods of the valley ? Or has 
 Walker, the botanist, been carrying him 
 about to visit vegetable patients, while you 
 are left to drudge among the animal ones ? 
 Is your head steady, or is it sometimes 
 [turning] round ? I have a thousand ques- 
 tions to ask about our [country] people, but 
 I ought rather to put them to those who 
 have more time to answer them. I was 
 very sorry to hear, by a letter from Lady 
 Forbes, of Hatton's misfortune, and am left 
 in doubt whether the next account shall be 
 of his death or recovery. 
 
 The common people here have a gloom 
 in their countenance, which I am at a loss 
 whether to ascribe to their religion or to the 
 air and climate. There is certainly more 
 of religion among the common people in 
 this town than in Aberdeen ; and, although 
 it has a gloomy, enthusiastical cast, yet I 
 think it makes them tame and sober. I 
 have not heard either of a house or of a 
 head broke, of a pocket picked, or of any 
 flagrant crime, since I came here. I have 
 not heard any swearing in the streets, nor 
 seen a man drunk, (excepting, inter nos, one 
 Prof r,) since I came here. If this scroll
 
 LETTERS TO DRS A. AND D. SKENE. 
 
 41 
 
 tire you, impute it to this, that to-raorrow 
 is to be employed iii choosing a Rector, and 
 I can sleep till ten o'clock, which I shall 
 not do again for six weeks ; and believe me 
 to be, with sincere friendship and regard, 
 dear Sir, yours, 
 
 Thomas Reid. 
 
 II. 
 
 TO DR DAVID SKENE. 
 
 Dear Sir, — We had a Turin Professor 
 of Medicine here lately, whom I wished you 
 acquainted with : Count Carburi is his 
 name ; an Athenian born, but has been 
 most of his tune Ln Italy.* He seems to be 
 a great connoisseur in natural history, and 
 has seen all the best collections in Europe. 
 The Emperor and King of France, as well 
 as many persons in Italy, he says, have 
 much more compleat collections of our 
 Scotch fossils than any we have in Britain. 
 I described to him our Bennachie porphyry ; 
 but he says all that they call porphyry in 
 Italy, consists of small dark-coloured grains, 
 in a grey ground, and lias very much the 
 same appearance as many of our granites, 
 before it is polished. He wanted much to 
 know whether we had any authentic evi- 
 dence from Ireland, or anywhere else, of 
 wood that had been seen in the state of 
 wood, and afterwards petrified. He would 
 have gone over to Ireland on purpose, if we 
 could have given him ground to expect this. 
 He says MM. Bufton and Daubenton are 
 both positive that no such thing was ever 
 known, and that all the petrified wood dug 
 up on various parts of the earth — of which 
 Carburi says he has two waggon-loads, found 
 in Piedmont — has been petrified before our 
 earth put on its present form ; and that 
 there is no evidence of any such petrifica- 
 tion now going on. I have a strong inclin- 
 ation to attend the chymical lecture here 
 next winter ; but am afraid I shall not 
 have time. I have had but very imperfect 
 hints of Dr Black's theory of fire. He has 
 a strong apprehension that the phlogistick 
 principle is so far from adding to the weight 
 of bodies, by being joyned to them, that it 
 diminishes it ; and, on the contrary, by 
 taking the phlogistick from any body, you 
 make it heavier. He brings many experi- 
 ments to prove this : the calcination of 
 metals, and the decomposition of sulphur, 
 you will easily guess to be among the num- 
 ber ; but lie is very modest and cautious in 
 his conclusions, and wants to have them 
 amply confirmed Ijcf'ore he assorts tlu;m 
 positively. 1 am told that Biack's theory 
 in not known at Edinburgh. Chemistry 
 
 ♦ 'ITiin wa» C'liiiit 1/ffrro,iint ( omit Mnrliio, Car. 
 hiirijtxiin at Crii/ialonia, and, Iniii n.jlMo IH()H, 
 J'rnletwr <)( C/iem($.'i !/ m rnriua.— W. 
 
 seems to be the only branch of philosopJiy 
 that can be said to be in a ])rogressive state 
 here, although other branches are neither 
 ill taught nor ill studied. As Black is got 
 into a good deal of jtractice, it is to be feared 
 that his chymical inquiries must go on slowly 
 and heavily in time to come. I never con- 
 sidered Dollond's telescopes till I came 
 here. I think they open a new field in op- 
 ticks which may greatly enrich that part of 
 philosophy. The laws of the refraction of 
 light seem to be very different, in difierent 
 kinds both of glass and of native chrystal. 1 
 have seen a prism of Brazil pelible, which 
 forms two distinct speculums in Sir I. New- 
 ton's experiment, each of them containing 
 all the primary colours. A German native 
 chrystal seemed to me to form four or five. 
 One composition of glass separates the 
 different colours much more than another 
 composition, even witli the same degree of 
 refraction. Dollond has made a fortune by 
 his telescopes, nobody else having attempted 
 to imitate them, and is now, I am told, 
 grown lazy. Nor is the theory of them 
 prosecuted as it ought. Dollond's micro- 
 meter is likewise a very fine instrument, 
 although not built upon anything new in 
 opticks. We have one of them here fitted to 
 a reflecting telescope of about 18 inches, 
 by which one may take the apparent diame- 
 ter of the sun, or of any planet, within a 
 second of a degree. 
 
 I find a variety of things here to amuse 
 me in the literary world, and want nothing 
 so much as my old friends, whose place I 
 cannot expect, at my time of life, to sup- 
 ply. I think the common people here and 
 in the neighbourhood greatly inferior to 
 the common people with you. They are 
 Boeotian in their understandings, fanatical 
 in their religion, and clownish in their dress 
 and manners. The clergy encourage this 
 fanaticism too much, and find it the only 
 way to popularity. I often hear a gospel 
 here whicli you know nothing about ; for 
 you neither hear it from the pulpit, nor 
 will you find it in the bible. 
 
 What is your Philosophical Society* do- 
 ing ? Still battling about D. Hume ? or 
 have you time to look in ? I hope your 
 papa holds out in his usual way. 1 beg to 
 be remembered to liini most affectionately, 
 and to all the rest of your family. But I 
 believe ynu do not like to be charged with 
 comi)liments, otlierwise I would desire of 
 you likewise to remember me respectfully 
 to Sir Archibald (irant. Sir Arthur and 
 Lady Forbes, and others of my country 
 
 • Thfr Philnsophiral Societv to which licit! here 
 al mips was (ouiulMl hv liiinsflf'niid his rplattvo Or 
 John Grc(;orv. It v as viilgarly Rtvliil the H ;«<• 
 Cluh Dr Daviil Ski'iip, who is callcil bv !iir V%. 
 Vi rl.cs " a |jh\Mr'aii "I Rciiius and la^lr," was one 
 III !tHorit;ipial mi iiiIkts. ^cc l-orbiB'n " l.ifc ol Hc»t. 
 lie," i. :t.'). — II.
 
 42 
 
 CORRESPONDENCE OF DR REID. 
 
 acquaintance, when you have occasion to 
 see them. I should be glad, too, to hear 
 from you, when leisure, and opportunity, and 
 the epistolary humour all meet together. 
 My folks are all pretty well, and beg their 
 compliments to you and all yours. — I am, 
 dear Sir, most affectionately, yours, 
 
 Thomas Reid. 
 Glasgow, 13 July 1765, 
 being the first warm day we 
 have had since the month of 
 May. 
 
 III. 
 
 TO DR DAVID SKENE. 
 
 Glasgow, 20 Dec. 1765. 
 
 Dear Sir, — Your commissions have 
 been lying by me some time, for want of a 
 proper conveyance. An Aberdeen carrier 
 promised to call for them, but disappointed 
 me ; I therefore sent the two thermometers 
 wrapt up in paper, and directed for you 
 by Mr. Menzies, merchant in the Narrow 
 Wynd, who was to set out from lience yes- 
 terday morning. One has a circular bore 
 in the small tube, the other an elliptical 
 one, and is on that account much fitter for 
 experiments. As there is a much greater 
 quantity of quicksilver in the circular one, 
 it may take four or five minutes to bring it 
 to the temperature of a fluid in which it 
 is immersed. For nice experiments, some 
 of the elliptical ones are made by Dr Wil- 
 son with the bulb of the small tube naked. 
 But these are so liable to accidents that 
 few choose them. The perspective machine 
 goes to Edinburgh to-morrow with Dr Trail, 
 who will send it to my sisters to be sent you 
 by the first proper opportunity. . . . 
 
 Mr Watt has made two small improve- 
 ments of the steam-engine. The first is in 
 the iron bars which support the fire. These 
 have always been made of solid iron, and 
 burn away so fast by the great heat, that the 
 expense of repairing them comes to be very 
 considerable. He uses hollow square bars 
 of plate iron, always kept full of water, 
 which communicates with a pretty large 
 reservoir, so that the bars can never be 
 heated above the degree of boyling water, 
 and may be kept far below that degree of 
 heat. The other improvement is to pre- 
 vent the waste of heat by the chimney pipe 
 of the furnace. It is evident that a very 
 large proportion of the heat of the fire 
 passes off in this way without being applied 
 to the water in the boyler. To prevent 
 this, he makes three small chimney pipes 
 of iron, which are made to pass through the 
 boyler. He is just now employed in setting 
 up an engine for the Carron Company with 
 these improvements. 
 
 Since I saw C. Carburi, I have it upon 
 good authority that there are petrifying 
 springs in England which petrify things 
 put into thera in a short time. And a 
 gentleman here expects, in a short time, a 
 petrified periwig from one of them. 
 
 Dr Black tells me that Cramer's fur- 
 naces, both for essaying and melting, as 
 you have them described in his " A rs Doci- 
 masticn," are the best he knows. His are 
 of this kind, being made of plate iron, 
 lined with a coat of a lute, which is com- 
 posed of one-part clay and three-parts fire- 
 sand, which, he says, never cracks. He 
 has not examined the Fechel earth, but con- 
 jectures it to be a composition of the same 
 kind with Prussian blue. He has seen a 
 horse's head, which, by being long buried in 
 a clay which had some mixture of iron, had 
 in several places taken a fine blue tinge, or 
 rather was covered with a fine blue dust. 
 
 I have attended Dr Black's lectures hith- 
 erto. His doctrine of latent heat is tlie. 
 only thing I have yet heard that is alto- 
 gether new. And, indeed, I look upon it 
 as a very important discovery. As Mr 
 Ogilvie attended him and took notes, I 
 believe he can give you a fuller account of 
 it than I can. It gives a great deal of light 
 to the phsenomena of heat that appear in 
 mixture, solution, and evaporation ; but, as 
 far as I see, it gives no light to those which 
 appear in animal heat, inflammation, and 
 friction. I wish this discovery may not 
 reach any person who may be so ungene- 
 rous as to make it public before the Dr 
 has time to publish it himself. If the ac- 
 count which Ogilvie can give you should 
 suggest any doubts, I will be glad to clear 
 them, so far as my knowledge of this doc- 
 trine reaches. — I am very glad to hear that 
 Dr Hope has a prospect of raising the true 
 rhubarb. I believe I forgot to tell you that I 
 wrapped up a head of what I take to be the 
 daucus sylvesiris, in a piece of paper, and 
 put it in the box with the drawing machine. 
 It grows in great plenty in the fields here ; 
 but I never saw it with you. I have not 
 met with any botanists here. 
 
 Our College is considerably more crowded 
 than it was last session. My class, indeed, 
 is much the same as last year ; but all the 
 rest are better. I believe the number of 
 our students, of one kind or another, may 
 be between four and five hundred. But the 
 College of Edinburgh is increased this year 
 much more than we are. The Moral 
 Philosophy class there, is more than double 
 ours. The Professor, Ferguson, is, indeed, 
 as far as I can judge, a man of a noble spirit, 
 of very elegant manners, and has a very 
 uncommon flow of eloquence. I hear he is 
 about to publish, I don't know under what 
 title, a natural history of man : exhibiting 
 a view of him in the savage state, and in
 
 LETTERS TO DRS A. AND D. SKENE. 
 
 43 
 
 the several successive states of pasturage, 
 agriculture, aud commerce. 
 
 Your friend, the Cte. de Lauraguais, 
 was very full of you when he was here, and 
 shewed an anxiety that your merit should 
 be known. I am told that he has wrote 
 many things in the ]\lemoirsof the Academy ; 
 but I know nobody here that has read them. 
 Our College Library is ten or twelve years 
 behind in the Memoirs of the Eoyal Aca- 
 demy ; and all that the Cte. has wrote must 
 fall within that period. He seems to have 
 attached himself so entirely to chemistry 
 as to have neglected every other branch of 
 knowledge. Carburi was more universal ; 
 he gave attention chiefly to the progress of 
 manufactures and commerce, and to col- 
 lect books and specimens of natural or artifi- 
 cial things. 
 
 Our society is not so harmonious as I 
 wish. Schemes of interest, pushed by some 
 and opposed by others, are like to divide us 
 into parties, and, perhaps, engage us in 
 law-suits.* When you see Mr W. Ogilvie, 
 please make ray com])Uments to him. I 
 received his letter, and will write him when 
 I can find leisure. I hope your pa[)a is 
 quite recovered of his cold, and that all the 
 rest of the family are in good health. Pray, 
 make my best compliments to him. Mrs 
 Reid, Pegie, and I, have all had a severe cold 
 and cough. I have been keeping the house 
 these two days, in order to get the better of 
 it.— I am, dear Sir, 
 
 Yours most affectionately, 
 
 Thomas Reid. 
 
 Ended, Dec. 30. 
 
 Wishing you many happy years. 
 
 IV. 
 
 TO DR ANDRKW SKENE. 
 
 Dear Sir, — I have been sometimes apt 
 to impute it to laziness, and sometimes to 
 hurry of business, that I have been so long 
 without writing you. I am ashamed to 
 plead tlie last of these excuses when I con- 
 sider how many people there are of my 
 acquaintance tliat have a great deal more 
 to do than I have, and would think all my 
 business but idleness. Yet, I assure you, 
 I can rarely find an hour which I am at 
 liberty to disjiose of as I please. The most 
 disagreeable thing in the teaching part is to 
 have a great number of stujiid Irish teagues 
 who attend classes for two or three years 
 to qualify them for teaching schools, or 
 being dissenting teachers. I preach to 
 these as St Francis did to the fishes. -f I 
 
 • See »t)Ove, p 40, A, below, pp. 46, A, and 17, }i. 
 All tlicory and all exi>eri»Mit(- prove, that the worst 
 and the nin*t c<'rriii)t depositaries of acadeir'cal pa. 
 ironape arc a scU-ilrciivc body of prolessors.— H. 
 
 ♦ Not St Francii), hut St Antony (of Tadua.)— H. 
 
 don't know what pleasure he had in his 
 audience ; but I should have none in mine 
 if there was not in it a mixture of reason- 
 able creatures. I confess I think there is 
 a smaller proportion of these in my class 
 this year than was the last, although the 
 number of the whole is not less. I have 
 long been of the opinion, that, in a right con- 
 stituted college, there ought to be two Pro- 
 fessors for each class — one for the dunces, 
 and another for those who have parts. 
 The province of the former would not be 
 the most agreeable, but, perhaps, it would 
 require the greatest talents, and, therefore, 
 ought to be accounted the post of honour. 
 There is no part of my time more disagree- 
 ably speut than that which is spent in 
 College meetings, of which we have often 
 five or six in a week. And I should have 
 been attending one this moment if a bad 
 cold I have got had not furnished me with 
 an excuse. These meetings are become 
 more disagreeable by an evil spirit of party 
 that seems to put us in a ferment, and, I 
 am afraid, will produce bad consequences. 
 
 The temper of our northern colonies 
 makes our mercantile people here look very 
 grave. Several of them are going to Lon- 
 don about this matter, to attend the pro- 
 ceedings of Parliament. It is said that tho 
 effects in those colonies belonging to this 
 town amount to above £400,000 sterling. 
 The mercantile people are for suspending 
 the stamp-act, and redressing the grievances 
 of the colonists. Others consider their 
 conduct as an open rebellion, and an avowed 
 claim to independence, which ought to be 
 checked in the beginning. They say that, 
 for all their boasting, the colonists are a das- 
 tardly, pusillanimous race, and that a Bri- 
 tish fieet and army would soon reduce them 
 to such terms as would secure their future 
 dependence upon the mother country; that 
 this is the most proper time for doing so 
 when we are at peace with all our neigh- 
 bours. In what light the House of Com- 
 mons will view this matter, I don't know, 
 but it seems to be one of the most import- 
 ant matters that have come before tliein. 
 I wish often an evening with you, such as 
 we have enjoyed in the days of former 
 times, to settle the important afi'airs of 
 State and Church, of Colleges and Corpora- 
 tions. I have found this the best expedient 
 to enable me to think of them without 
 melancholy and chagrin. And I think all 
 that a man has to do in the world is to 
 keep his tenij)er and to do his duty. 
 Mrs Reid is tolerably well just now, but is 
 often ailing. She desires to be remenibered 
 to you and all your iamily.— I am, dear Sir, 
 Yours most affectionately, 
 Thomas Ukid. 
 
 Glasyou. Dec. 30, 1705.
 
 44 
 
 CORRESPONDENCE OF DR REID. 
 
 TO DR I>AVID SKENE. 
 
 Glasgow, 23 March I766. 
 Dear Sir, — I had yours of the 14th, 
 and this moment that of Thursday the 20, 
 with the inclosed, a letter from your papa 
 by Mr Duguid, with your circular thermo- 
 meter. I returned the thermometer, re- 
 paired by Mr Annan, who left this two days 
 ago, but was to be a week at Edinburgh in 
 his return. I shall remember Sir Archi- 
 bald Grant's commission, but must take 
 some time to think of it. What would you 
 think of Alex. Mearns in Gordon's Hospi- 
 tal ? If you are not acquainted with him, 
 you may learn his qualities, and tell me 
 your sentiments. I shall likewise mind your 
 elliptical thermometer. Mr Stewart's* death 
 affects me deeply. A sincere friendship, 
 begun at twelve years of age, and continued 
 to my time of life without any interruption, 
 cannot but give you some pangs. You 
 know his worth, yet it was shaded ever 
 since you knew him by too great abstraction 
 from the world- The former part of his life 
 was more amiable and more social, but the 
 whole was of a piece in virtue, candour, and 
 humanity. I have often regretted that the 
 solicitude of providing for a numerous family, 
 and the labour of managing an -estate and a 
 farm, should make a man in a great measure 
 unknown, whose virtue, integrity, and judg- 
 ment ought to have shone in a more exten- 
 sive sphere. His scholars could not but 
 observe and revere his virtues ; and I have 
 no doubt but great numbers of them have 
 reaped great improvement by him in matters 
 of higher importance than mathematical 
 knowledge. I have always regarded him as 
 my best tutor, though of the same age with 
 me. If the giddy part of my life was in any 
 degree spent innocently and virtuously, I 
 owe it to him more than to any human 
 creature ; for I could not but be virtuous in 
 his company, and I could not be so happy 
 in any other. But I must leave this pleas- 
 ing melancholy subject. He is happy; and 
 I shall often be happy in the remembrance 
 of our friendship ; and I hope we shall meet 
 again. 
 
 There is no such thing as chjTnical fur- 
 naces made here tor sale. They are made 
 of plate iron; and a white-iron-man manages 
 that material better than a blacksmith. But 
 you must direct them in everything, and be 
 still over tlie work. 
 
 I can give but an imperfect account of 
 
 • John Stuart, Professor of Mathematics in 
 Marischal Collefte. This ch -ir is in the presentation 
 of the Town Council of Aberdeen ; and on the va- 
 cmcy, by Smart's death, Dr Keidwas aiipointed one 
 of the examinators of candidates lor the office — H- 
 
 the doctrine of latent heat ; but some liint 
 I shall give, trusting entirely to your honout 
 that you will be cautious not to make any 
 use of it that may endanger the discoverer 
 being defrauded of his property. 
 
 There is in every body a certain quantity 
 of heat, which makes a part of its form or 
 constitution, and which it never parts with 
 without losing or changing its form. This is 
 called the latent heat of that body. All or 
 most bodies have three different forms — 
 hardness, fluidity, and steam or vapour. 
 Take water, for an example, in its hard state, 
 that of ice : we have no means of knowing 
 what latent heat it may contain ; but in its 
 fluid state it has about 140° of latent heat 
 more than it had in the state of ice. This 
 heat is latent while the water is fluid ; it 
 does not affect the thermometer, nor pro- 
 duce any other effect but that of making the 
 body fluid. In the very act of melting from 
 the state of ice to that of water, 140° of heat 
 is absorbed from the circumambient bodies 
 without making the water sensibly warmer 
 than the ice ; and in the act of passing from 
 the state of water to that of ice, 140° of heat 
 which was latent in the water becomes sen- 
 sible, and must pass from the water to the 
 ambient bodies before it can wholly be con- 
 verted into ice. As there is no intermediate 
 state between water and ice, a very small pari 
 of the water freezes at once ; and the latent 
 heat of that part being communicated to the 
 remaining water, the freezing even in the 
 coldest air goes on piecemeal, according as 
 the latent heat goes off first into the water 
 not yet frozen, and from that into the air or 
 ambient bodies. 
 
 Spermaceti, in passing from a solid to a 
 perfectly fluid form, requires about 150'^ 
 of heat, which becomes latent ; bees' wax 
 about 160°. But there is this remarkable 
 difference between these bodies — as well as 
 iron and some other metals on the one 
 hand, and water on the other — that the 
 former soften by degrees, so that there are 
 many intermediate degrees of softness be- 
 tween the hardest state which the body 
 takes by cold, and the state of perfect 
 fluidity ; whereas in water there seems to 
 be no intermediate degree between perfect 
 ice and perfect water. Accordingly, in 
 spermaceti, bees' wax, and iron, the latent 
 heat is more or less, according to the de- 
 gree of softness ; but in water it is always 
 the same. As water has about 140° of 
 latent heat more than ice, so steam has 
 about 800° of latent heat more than water ; 
 hence, an ounce of steam, though it have 
 little more sensible heat than boyling water, 
 will heat the cold water that condenses it 
 almost as much as four ounces of boyling 
 water would do. I can only at present 
 give you an experiment or two of the many 
 by which this tlieory is confirmed. But
 
 LETTERS TO DRS A. AND D. SKENE. 
 
 45 
 
 first, it 13 proper to observe, that equal 
 quantities of the same fluid of different 
 temperatures, being mixed, tlie tempera- 
 ture of the mixed fluid is always an arith- 
 metical mean between the temperatures of 
 the ingredients. Thus, if a pound of water 
 of 40° be mixed with a pound of 100", the 
 mixed is found precisely (iO^. This has been 
 tried in an infinite variety of cases, and 
 found to hold invariably, proper allowance 
 being made for the heat communicated to 
 the vessels, or drawn from them in the 
 operation. 
 
 Experiment 1. — Two Florence flasks had 
 six ounces of water put into each. In one 
 it was made to freeze ; in the other brought 
 as near as possible to the freezing point 
 without freezing — that is, to about 'S'S\ 
 Both were set to warm in a large warm 
 room. The unfrozen water soon came to 
 the temperature of the room ; but the frozen 
 water took eleven or twelve hours to dis- 
 solve, and for the greatest part of that time 
 was not sensibly heated. A calculation 
 was made upon the supposition that the 
 frozen water had as much heat communi- 
 cated to it every half hour as the unfrozen 
 water had the first half hour. The result 
 of this calculation was, that the frozen 
 water had absorbed I'dG' or 140° of heat in 
 melting, over and above that which affected 
 the thermometer. 
 
 Exp. 2. — Six ounces of ice of the tem- 
 perature of 32° had six ounces of boyling 
 water poured upon it. The ice melted im- 
 mediately, and the whole water was 52° 
 temperature. 
 
 Exp. 3. — From Musschenbroek, with a 
 little variation. WJien the air is ten degrees 
 below the freezing point, set a deep, narrow 
 beer-glass of water to freeze, and let it re- 
 main perfectly at rest, without the least 
 motion. Tlie water will cool regularly 
 below 32° without freezing, even to 22° ; 
 but, as soon as it is disturbed, a number of 
 icy spiculte are formed ; and in the same 
 moment the sensible heat rises to 32°, and 
 contiimes so till all is frozen. 
 
 I need not tell you, that by sensible heat 
 is meant that wliich diffuses itself to the 
 ambient bodies till all are brought to an 
 equilibrium. Of this the thermometer is 
 the measure. But latent heat adheres to 
 the body without any tendency to diffuse 
 itself to other bodies, unless they are able 
 to change the foi m of the body from vapour 
 to a fluid, or from a fluid to iceorhardncss — 
 then the latent heat goes off to otiier bodies, 
 and becomes sensible. I liope you will un- 
 derstand me, tJiough I have wrote in a great 
 hurry. Yet I cannot find that Culien or 
 the Ivlinburgh people know anything of this 
 matt(.T. I may give y(;u more of tliu ex- 
 periments afterwards. 
 
 Thomas Ram. 
 
 VI. 
 
 TO DR DAVID SKENE. 
 
 G/as„ow, l8lJi April [176G.] 
 Dear Sin, — There is like to be a vacancy 
 in one of the medical professions of this col- 
 lege, by the I'emoval of .Joseph Black to 
 Edinburgh. I thought, when I heard of 
 Dr White's death, that there was very little 
 probability of our losing Dr Black by that 
 event ; because the Clnniical Profession in 
 Edinburgh was that which was thought 
 fittest for Dr Black ; and there was good 
 reason to think that Culien would not give 
 up the Chemistry for the Theory of Medi- 
 cine—though he would very willingly ex- 
 change it for the Practice of Medicine. 
 But I was informed late yesternight, that 
 Dr Black is willing to accept of the Theory 
 of Medicine in Edinburgh, and that the 
 Council are certainly to present him. I 
 am very dubious whether his place here 
 would be worth your accej)tance ; but I am 
 sure it would be so much the mterest of 
 this society to have such a man in it, (and 
 I need not say how agreeable it would be 
 to me,) that I beg leave to inform you of 
 what 1 know of -the state of the matter, 
 that you may think of it, and let me know 
 your thoughts. The salary of Dr Black's 
 place, is £50 as Professor of the Theory and 
 Practice of Medicine ; and the presentation 
 is in the Crown. The recommendation of the 
 College would probably have great weight, 
 if unanimous ; but I think there is no pro- 
 bability of an unanimous recommendation ; 
 so that the Court interest must probably 
 determine it. Dr Black, and Dr Culien be- 
 fore him, had £20 yearly from the College, for 
 teaching chemistry ; and the College have, 
 from time to time, allowed, I believe, above 
 £500 for a laboratory. The chemical class 
 this session might bring £50 or £G0 of fees, 
 and the medical class from £20 to £30; so 
 that the wIkjIc salary and fees will be between 
 £140 .and £100. At th. same time, the 
 College can at any time withdraw the £20, 
 and give that and the chemical laboratory to 
 another ; and it is not improbable that this 
 may be done if one be presented of whose 
 al)ilities in clu^mistry tlie College is not 
 satisfied. Dr Black, of late, had got a 
 great deal of practice in Ijie medical way, 
 so as to leave him but little time for prose- 
 cuting his chemical discourses, and I think 
 you might expect the same after some time; 
 for he had no natural connectinn hero: it 
 was his merit alone that brought him into 
 it; and he long resisted, instead of courting 
 it ; so that it was in a manner forced ujioil 
 him. The other medical Professor has 
 anatomy and botany for his jiroviiice ; Jie 
 lias a jiiMid analonn'cal class; but he doea
 
 46 
 
 CORRESPONDENCE OF DR REID. 
 
 not teach botany at all, nor is, as I appre- 
 hend, qualified to teach it. All I have far- 
 ther to say is, that there is a great spirit of 
 inquiry here among the young people. Lite- 
 rary merit is much regarded ; and I con- 
 ceive the opportunities a man has of improv- 
 ing himself are much greater than at Aber- 
 deen. The communication with Edinburgh 
 is easy. One goes in the stage-coach to Edin- 
 burgh before dinner ; has all the afternoon 
 there ; and returns to dinner at Glasgow 
 next day : so that, if you have any ambition 
 to get into the College of Edinburgh, (which, 
 I think, you ought to have,) I conceive 
 Glasgow would be a good step. Now, sir, 
 if you incline this place, you must, without 
 delay, try your interest at Court, and get 
 the best recommendations you can to the 
 members of this College. The Principal and 
 Mr Clow are not engaged ; they are the 
 only persons to whom I have made known, 
 or intend to make known, my writing to you. 
 Lord Findlater's interest, I think, would 
 have weight with Trail and Williamson. I 
 am told of three candidates — Dr Stevenson, 
 in Glasgow; Dr Smith Carmichael, a young 
 doctor, presently at London ; and one Dr 
 Stork, who was educated here. Each of 
 these, I apprehend, has interest with some 
 of the members, and depend upon them ; so 
 that we will probably be divided, and, con- 
 sequently, our recommendation, if any is 
 given, will have little weight at Court. If, 
 after due deliberation, you tliink it not worth 
 your while to stir in this matter for yourself, 
 will you be so good as communicate the state 
 of the case to Dr George Skene ?* He is the 
 man — that is, next to you — I would be fond 
 of for a colleague ; and in this I think I am 
 determined more by the public good than 
 my private. 
 
 VIL 
 
 TO UR ANDREW SKENE. 
 
 Dear Sir, — I cannot presently lay my 
 hand upon the last letter I had from you, 
 and I beg you will impute it to that and to 
 my bad memory if there was anything in it 
 I ought to answer. I have sent by the 
 bearer, Mr Duguid, merchant in Aberdeen, 
 an elliptical thermometer for Dr David, 
 which I could not find an opportunity of 
 sending till now. Mrs Reid was, this day, 
 at one in the afternoon, brought to bed of a 
 daughter, whom we have named Elizabeth, 
 and I hope is in a good way 
 
 We liave had great canvassing here about 
 
 * A third Ahe»donian physician of distinction, ot 
 the name of Skene, but not a relation, at least not a 
 near relation, ol the other two He was Protessoi of 
 Philosophy, Marischal C ollege; an eminent scholar; 
 and father of the late Solicitor.General._H. 
 
 a Professor of the Theory and Practice of 
 J'hysic, to succeed Dr Jo. Black, although 
 all that we do is to recommend one to the 
 King, who has the presentation. Dr 
 Stevenson, a son of the late Dr Stevenson 
 in Edinburgh, who has by much the best 
 practice in this town and neighbourhood, 
 has obtained a recommendation from the 
 majority of the College, not without much 
 interest. The only objection to him was 
 his great practice, which it was thought 
 might tempt liim to neglect regular teach- 
 ing. And, I believe, the majority would 
 have preferred to him any man of character 
 wlio had not such a temptation to neglect 
 the duties of his office. However, the 
 strongest assurances that he would not ne- 
 glect the class— nay, that he would think 
 himself bound in honour to give up the 
 Profession if he could not keep up a class, 
 brought in a majority to sign a recom- 
 mendation in his favour ; and, as he has a 
 strong interest at Court, and no rival, as 
 far as we know, it is thought he will be the 
 man. He declines teaching the chemistry 
 class, which is in the gift of the College, 
 and, I conceive, will be given to one of Dr 
 Black's scholars. My class will be over in 
 less than a month, and by that time I shall 
 be glad to have some respite. I hope to 
 have the pleasure of seeing my friends at 
 Aberdeen in the month of August, if not 
 sooner. We have had a thronger College 
 this year than ever before. I had som« 
 reason to think that I should not have so 
 good a class as last year, and was dis- 
 appointed, for it was somewhat better. I 
 expect a good one next winter, if I live so 
 long. The Irish, on whom we depend 
 much, have an ebb and flow, as many of 
 them come but one year in two. We have 
 been remarkably free from riots and dis- 
 orders among the students, and I did not 
 indeed expect that 350 young fellows could 
 have been kept quiet, for so many months, 
 with so little trouble. They commonly 
 attend so many classes of different profes- 
 sors, from half-an-hour after seven in the 
 morning till eight at night, that they have 
 little time to do mischief. 
 
 You'll say to all this that cadgers are aye 
 speaking of crooksaddles. I think so they 
 ought ; besides, I have nothing else to say 
 to you, and I have had no time to think of 
 anything but my crooksaddles for seven 
 months past. When the session is over I 
 must rub up my mathematicks against the 
 month of August. There is one candidate 
 for your Profession of Mathematicks to go 
 from this College ; and, if your College get a 
 better man or a better mathematician, they 
 will be very lucky. I am so sensible of the 
 honour the magistrates have done me in 
 naming me to be one of the examinators, 
 that I will not decline it, though, I confess,
 
 LETTERS TO DRS A. AND D. SKENE. 
 
 47 
 
 I like the honour better than the office — 
 I am, dear Sir, 
 
 Yours most affectionately, 
 
 Thomas Reid. 
 Glasgow, 8th May, 1766. 
 Half an hour after eleven at night. 
 
 VIII. 
 
 TO DR ANDREW SKENE. 
 
 When you are dis- 
 posed to laugh you may look into the in- 
 closed proposals from a physician here who 
 has been persecuting everybody with an 
 edition of Celsus, and now with an index to 
 him as large as the book. Another physi- 
 cian here is printing a History of Medicine, 
 and of all the arts and sciences from the 
 beginning to the present time, four vols. 
 8vo, price one guinea. He is not thought 
 mad, but whimsical. I have not the pro- 
 posals to send you, and I suppose I have 
 sei.t enough of this kind. We authors had 
 rather be known for madmen or fools than 
 pass our lives in obscurity. Stevenson's 
 presentation to the Profession of Medicine 
 here is not yet come, but is expected as cer- 
 tain. The College have appointed a Lec- 
 turer in Chemistry, and one in Materia 
 Medica, for next session. I think we might 
 have a college of medicine here if we had 
 an infirmary. I think our surgeons eclipse 
 our M.D's. I do not hear much of the 
 last, if you except Black and Stevenson. 
 Our Professor of Anatomy is not an M.D., 
 otherwise I would have excepted him also. 
 Have you ever tried the seeds of the dau- 
 cus sylveslrh in nephritick cases ? It has 
 been much t.ilked of of late. I never saw 
 it in the north, but it is pretty common in 
 the fields here. — I am, dear Sir, 
 
 Yours most affectionately, 
 
 THo^fAS Reid. 
 
 C.lasyow. lolh Juli/ 1/66. 
 
 IX. 
 
 TO DR ANDRKW SKENE. 
 
 GlasffMv College, Dec. 17, 1766. 
 
 ... I live now in the College, and 
 have no disUmce to walk to my class in 
 dark mornings, as I had before. I enjoy 
 tliis case, though I am not sure whether 
 the necessity of walking up and down a 
 steep hill three or four times a-day, was not 
 of use. I have of late had a little of your 
 distemper, finding a giddiness in my head 
 when I lie down or rise, or turn myself in 
 my bed. 
 
 Our College is very well peopled this 
 eeHsion ; my jiublic claHM is above three 
 
 score, besides the private class. Dr Smith 
 never had so many in one year. There is 
 nothing so xmeasy to me here as our fac- 
 tions in the College, which seem to be 
 rather more infiamed than last session. 
 
 Will you take the trouble to ask of Dr 
 David, whether he knows of a bird called 
 a stankhen.* It is a water fowl, less than 
 a duck, with scolloped membranes at the 
 toes, but not close-footed, and has a crest 
 on the forehead of the same kind of sub- 
 stance with a cock's comb, but whiteand flat. 
 It has a very fishy taste, and is found here 
 in the lochs. If he has none of this kind, 
 I could send him one when I find a proper 
 occasion. I am, with entire affection and 
 regard, dear Sir, yours, 
 
 Thomas Reid. 
 
 X. 
 
 TO DR DAVID SKENE. 
 
 G/a^gow College, 25'A Feby. I767. 
 
 Dear Sir, — I intend to send your stank- 
 hen along with the funiace, which was 
 ready long ago, and I suppose would have 
 been sent before now, but that Dr Irvine 
 was confined a long time by a megrim, and 
 was like to lose one eye by it ; but is now 
 pretty well recovered, and intends to send 
 your furnace this week. 
 
 Since the repeal of the stamp-act, trade, 
 which was languishing, has revived in this 
 place, and there is a great bustle and great 
 demand for money. We are now resolved 
 to have a canal from Carron to this place, 
 if the Parliament allows it. £40,000 was 
 subscribed last week by the merchants and 
 the Carron Company for this purpose ; and 
 commissioners are immediately going up 
 to London to apply for an act of Parlia- 
 ment. The freight upon this canal is not 
 to exceed twopence per ton for every mile ; 
 the land carriage is more than ten times as 
 much. 
 
 Our medical college has fallen off greatly 
 this session, niost of tlie students of medi- 
 cine having followed Dr Black ; however, 
 our two medical professors and two lec- 
 turers have each of them a class, and Irvine 
 expects a great many to attend him for 
 botany in summer. The natural .and moral 
 philoso])hy classes are more numerous than 
 they have ever been ; but I expect a great 
 falling off, if 1 see; another session. The 
 Lecturer in Chemistry has general approba- 
 tion. He chiefly follows Dr Black and 
 Stalil. Tiiere is a book of Stahl's, called 
 " Three Hundred Exjx riments," which ho 
 greatly admires, and very often quotes. I 
 was just now seeing your furnace along with 
 
 ♦ The RalliiiuU Chloropus. — H.
 
 48 
 
 CORRESPONDENCE OF DR REID. 
 
 Irvine ; I think it a very decent piece of 
 furniture for a man of your profession, and 
 that no limb of the faculty should be without 
 one, accompanied with a proper apparatus 
 of retorts, cucurbits, &c. For my part, if 
 I could find a machine as proper for ana- 
 lyzing ideas, moral sentiments, and other 
 materials belonging to the fourth kingdom, 
 I believe I should find in my heart to be- 
 stow the money for it. I have the more 
 use for a machine of this kind, because my 
 alembick for performing these operations — 
 I mean my cranium — has been a little out 
 of order this winter, by a vertigo, which 
 has made my studies go on heavily, though 
 it has not hitherto interrupted my teaching. 
 I have found air and exercise, and a clean 
 stomach, the best remedies ; but I cannot 
 command the two former as often as I could 
 wish. I am sensible that the air of a 
 crowded class is bad, and often thought of 
 carrying my class to the common hall ; but 
 I was afraid it might have been construed 
 as a piece of ostentation. I hope you 
 are carrying on your natural history, or 
 something else, in the Club, with a view to 
 make the world wiser. What is my Lord 
 Linnseus doing ? Are we ever to expect 
 his third volume upon the fossile kingdom 
 or not ? We are here so busie reading lec- 
 tures, that we have no time to write. . . . 
 
 XI. 
 
 TO UK DAVID SKENE. 
 
 Glasgow Col'ege, 14 Sepf. 1767. 
 Dear Sir, — It gives me much surprise, 
 as well as aftliction, to hear from niv daughter 
 Patty, of the death of my dear friend, your 
 papa. Fifteen years ago it would have been no 
 surprise ; but for some years back, I thouglit 
 there was great probability that his life aud 
 usefulness might have had a longer period. 
 I can never, while I remember anything, 
 forget the many agreeable hours I have en- 
 joyed with him, in that entire confidence 
 and friendship which give relish to life. I 
 never had a friend that shewed a more 
 hearty affection, or a more uniform dispo- 
 sition to be obliging and useful to me and 
 to my family. I had so many opportuni- 
 ties of observing his disinterested concern 
 to be useful in his profession to those from 
 whom he could expect no return, his sym- 
 pathy with the distressed, and his assiduity 
 m giving them his best assistance, that, if 
 I had had no personal friendship with him, 
 I could not but lament his death as a very 
 great and general loss to the place. It is 
 very uncommon to find a man that at any 
 time of life, much more at his, possessed 
 the active, the contemplative, and the social 
 disposition at once in so great vigour. I 
 
 sincerely sjTnpathize with you ; and I beg 
 you will assure each of your brothers and 
 sisters of my sympathy ; and that, besides 
 my personal regard to every one of them, 
 I hold myself to be under the strongest 
 obligation from gratitude and regard to the 
 memory of my deceased friend, if I can 
 ever be of the least use to any of them. 
 
 You are now, dear Sir, in the providence 
 of God, called to be a father as well as a 
 brother ; and I doubt not but you will ac- 
 quit yourself in that character as y<m have 
 done in the other. I need not say that Dr 
 Skene's death gave very great affliction to 
 Mrs Reid and to all my family ; they all 
 desire that you and all your family may be 
 assured of their respect and sympathy. . . . 
 
 Some days alter I parted from you at 
 Edinburgh, I was called home to do the 
 last duty to my sweet little Bess, whom I 
 had left in perfect health some days after 
 her innoculation. Since that time I have 
 not been three miles from Glasgow, but 
 once at Hamilton with Mr Beattie. Hav- 
 ing my time at command, I was tempted 
 to fall to the tumbling over books, as we 
 have a vast number here which I had not 
 access to see at Aberdeen. But this is a 
 mare 7na(/iinm, wherein one is tempted, by 
 hopes of discoveries, to make a tedious voy- 
 age, which seldom rewards his labour. I 
 have long ago found my memory to be like 
 a vessel that is full ; if you pour in more, 
 you lose as much as you gain ; and, on this 
 account, have a thousand times resolved to 
 give up all pretence to what is called learn- 
 ing, being satisfied that it is more profitable 
 to ruminate on the little I have laid up, 
 than to add to the indigested heap. To 
 pour learning into a leaky vessel is indeed 
 a very childish and ridiculous imagination. 
 Yet, when a man has leisure, and is placed 
 among books that are new to him, it is 
 difficult to resist the temptation. I have 
 had little society, tiie college people being 
 out of town, and have almost lost the 
 faculty of speech by disuse. I blame my- 
 self for having corresponded so little with 
 my friends at Aberdeen. 
 
 I wished to try Linnoeus's experiment, 
 which you was so good as to communicate 
 to me. I waited for the heat of summer, 
 which never came till the first of August, 
 and then lasted butJa few days. Not hav- 
 ing any of the fungus ])owder at hand, I put 
 a piece of fresh fungus which grew on rot- 
 ten wood ill pure wafer. In a day or two 
 I found many animalcules diverting them- 
 selves in the water by diving and rising 
 again to the top. But, after three or four 
 days, the water turned muddy and stunk. 
 And, from all I could then observe, I should 
 rather have concluded that my animalcules 
 died and putrified, than that they were 
 transformed into young mushrooms. I see
 
 LETTERS TO DRS A. AND D. SKENE. 
 
 49 
 
 H. letter iu The Edinhirgh Courantoi Wed- 
 nesday last on tliis subject. About twenty 
 hours ago, I put some smutty oats in water ; 
 but have not seen any animals in it 
 yet. A nasry custom I have of chewing 
 tobacco has been the reason of my observ- 
 ing a species of as nasty little animals. On 
 the above occasion, I spit in a bason of saw- 
 dust, which, wlieu it comes to be drenched, 
 produces a vast number of animals, three 
 or four times as large as a louse, and not 
 very different iu shape; but armed with four 
 or five rows of prickles like a hedgehog, 
 W'hich seem to serve it as feet. Its motion 
 is very sluggish. It lies drenched in the 
 foresaid mass, whicli swarms wi:li these 
 animals of all ages from top to bottom ; 
 whether they become winged at last I have 
 not discovered. 
 
 Dr Irvine was taken up a great part of 
 the summer w ith his botanical course ; and, 
 since that was over, has been in the country. 
 I have gone over Sir James Stewart's great 
 book of political ceconomy, wherein I think 
 there is a great deal of good materials, care- 
 lessly put together indeed ; but I think it 
 contains more sound principles concerning 
 commerce and police than any book we have 
 yet had. We had the favour of a visit from 
 Sir Archibald Grant. It gave me much 
 pleasure to see him retain his spirits and 
 vigor. I beg when you see him you w ill make 
 my best compliments to him. I beg to be 
 remembered to the Club, which I hope goes 
 on with spirit. I am, with great regard, 
 dear Sir, yours most affectionately, 
 
 Thomas Reid. 
 
 Be so good as to put the inclosed into 
 Sandie Leslie's shop. 
 
 XII. 
 
 TO DK DAVID SKENE. 
 
 Dear Sir, — You will easily guess that 
 my chief motive in writing you at this time, 
 is, by the benefit of your frank, to save the 
 postage of the two inclosed, of wliieh I give 
 you the trouble. Perhaps I would have dis- 
 sembled this, if I had had anything to say. I 
 long to hear how Liniueus' ex])eriment has 
 succeeded with you. For my own part, I 
 havefound nothing about it but what I wrote 
 you before. The chymists here are hunting 
 for something l)y whidi cambrick may bo 
 stamjied as it comes from tJio loom, so that 
 the stamps shall stand out all tlic operations 
 of boyjing, bleacliing, &c. Tlie only thing 
 that is like to answer, I am told, is that solu- 
 tion of silver which is used to dye ivory black. 
 The act of Parliament anent cambrick re- 
 quires it to be stamped in the loom ; and, if 
 this stamj) is not a])iiaront after bleaching, 
 it is contraband. But the wisdom of the 
 
 nation has not thought fit to prescribe the 
 material to be used for that purpose ; if no 
 such material is found, the act will be use- 
 less. 
 
 I passed eight days lately with Lord 
 Kaims at Blair-Drummond. You were 
 very honourably mentioned. My Lord has 
 it much at heart to have a professor of 
 practical mechanicks established at Edin- 
 burgh, and wants only a proper person. 
 He is preparing a fourth edition of his 
 " Elements." I have been labouring at 
 Barbara Celareiit for three weeks by- 
 gone ;• and on IMonday begin my own 
 course. I do not expect such a crop of 
 students as I had last year ; but the Col- 
 lege in general promises pretty well. I\Iy 
 compliments to all your family ; and believe 
 me to be, with great affection, dear Sir, 
 
 Yours, 
 Thomas Reid. 
 
 Glasgow College, 31 Oct. 11^1. 
 
 XIII. 
 
 TO DR DAVID SKENE. 
 
 [July XnO.] 
 Dear Sir, — Having this opportunity, I 
 could not forbear asking how you do, and 
 what you are doing. I know you are giv- 
 ing feet to the lame, and eyes to the blind, 
 and healing the sick. 1 know you are 
 gathering heaps of fossils, vegetables, and 
 animals, and I hope among other fossils you 
 are gathering gold and silver; this is all very 
 right. I know, likewise, that you have been, 
 ever since you was in petticoats, most avari- 
 ciously amassing knowledge. But is it all to 
 die with you, and to be buried in your grave ? 
 This, my dear sir, ought not to be. You 
 see we Scotch people will be blotting paper 
 though you should hold your hand : siu!li,m 
 est pvrUurcB parcere chnr ce. Can you find 
 no time, either when you are laid up in the 
 gout, or when the rest of the world is in 
 good health, to bequeath sf ir.etliing to pos- 
 terity ? Think seriously of this, if you have 
 not done so already. Permit me, sir, to 
 ofier you another couusell; for you know we 
 moralists know better how to give good 
 counsell than to take it. Is it not possible 
 for you to order things so as to take a jaunt 
 of six weeks ortwomonths? 1 verily believe 
 there are things worth knowing here, much 
 more at Edinburgh, of \vl)ich you cannot be 
 fully informed while you keep be-north Tay. 
 We have sj)eculatists in medicine, in chem- 
 istry, in mechanics, in natural h.istury, tluit 
 are worth being acquainted with, and that 
 
 * This allucIcH to his " Analysis of Aristntle's I o- 
 ((ic," which he was ihcii prcpariiig as an A|>|ifniliX 
 to (IMP nC Lord Kaiiics'ii" Sketches of the History (il 
 Mail ■•— H. 
 
 V.
 
 50 
 
 CORRESPONDENCE OF DR REID. 
 
 would be fond of your acquaintance. As 
 to myself, the immaterial world has swal- 
 lowed up all my thoughts since I came here ; 
 but I meet with few that have travelled far 
 in that region, and am often left to pursue my 
 dreary way ui a more solitary manner than 
 
 when we used to meet at the club. What ia 
 LinniBus doing ? When you have leisure, 
 indulge me with the pleasure of knowing 
 that you have not forgot, dear Sir, your 
 affectionate friend, 
 
 Thomas Reid. 
 
 B.— LETTERS TO LORD KAMES. 
 
 ON THE DOCTRINE OF NECESSITY IN RELA- 
 TION TO MORALS. 
 
 Glasgow College, 3d Dec. 1772. 
 
 Mv Lord, — I was very glad to under- 
 stand, by the letter you honoured me with 
 of >Jovember 9, that you got safe home, 
 after a long journey, in such dreadful rainy 
 weather. I got to Mr C 's on horse- 
 back soon after you left me, where I was 
 in good warm quarters. 
 
 The case you state is very proper, to dis- 
 cover how far we differ with respect to the 
 influence of the doctrine of necessity upon 
 morals. 
 
 A man in a mad fit of passion stabs his 
 best friend ; immediately after, he condemns 
 himself ; and, at last, is condemned by a 
 court of justice, although his passion was 
 no less irresistible than if he had been 
 pushed on by external violence. 
 
 My opinion of the case, my Lord, is this : 
 if the passion was really as irresistible as 
 you represent it, both in its beginning and 
 progress, the man is innocejit in the sight 
 of God, who knows that he was driven as 
 by a whirlwind, and that, the moment he 
 was master of himself, he abhorred the 
 action as much as a good man ought to do. 
 
 At the same time, he reasonably may 
 condemn himself, and be condemned by 
 a court of justice. 
 
 He condemns himself, because, from his 
 very constitution, he has a conviction that 
 his passion was not irresistible. Every 
 man has this conviction as long as he be- 
 lieves himself not to be really mad, and 
 incapable of self-government. Even if he 
 is a fatalist in speculation, that will not 
 hinder this natural conviction when his 
 conscience smites him, anymore than specu- 
 lative scepticism will hinder a man from 
 apprehension of danger when a cart runs 
 against him. 
 
 The court of justice condemns him for the 
 same reason, because they believe that his 
 passion was not irresistible. But, if it could 
 be proved that the man was really incapa- 
 ble of bridling his passion — that is, that he 
 was really mad— then the court of justice 
 
 ought not to punish him as a criminal, but 
 to confine him as a madman. 
 
 AVhat is madness, my Lord ? In my 
 opinion, it is such weakness in the power of 
 self-government, or such strength of pas- 
 sion, as deprives a man of the command of 
 himself. The madman has will and inten- 
 tion, but he has no power to restrain them. 
 If this madness continues so long as to be 
 capable of proof from the tenor of a man's 
 actions, he is no subject of criminal law, 
 because he is not a free agent. If we sup- 
 pose real madness to continue but for a 
 moment, it makes a man incapable of a 
 crime, wliile it lasts, as if it had continued 
 for years. But a momentary madness can 
 have no effect to acquit a man in a court 
 of justice, because it cannot be proved. It 
 would not even hinder him from condemn- 
 ing himself, because he cannot know that 
 he was mad. 
 
 In a word, if, by a mad fit of passion, 
 your Lordship means real madness, though 
 temporary, and not permanent, the man is 
 not criminal for what this fit of madness 
 produced. A court of justice would not 
 impute the action to him, if this could be 
 proved to be the case. But if, by a mad 
 fit of passion, you mean only a strong pas- 
 sion, which still leaves a man the power of 
 self-government, then he is accountable for 
 his conduct to God and man ; for every 
 good man — yea, every man that would avoid 
 the most heinous crimes— must at some 
 times do violence to very strong passions. 
 But hard would be our case indeed, if we 
 were required, either by God or man, to 
 resist irresistible passions. 
 
 You think that will and intention is suf- 
 ficient to make an action imputable, even 
 though that will be irresistibly determined. 
 I beg leave to dissent, for the following 
 reasons : — 
 
 1 A n invincible error of the understanding, 
 of memory, of judgment, or of reasoning, is 
 not imputable, for this very reason, that it is 
 invincible : why, then, should an error of the 
 will be imputable, when it is supposed equally 
 invincible ? God Almighty has given us 
 various powers of understanding and of will. 
 They are all equally his workmanship. Our
 
 LETTERS TO LORD KAMES. 
 
 51 
 
 understandings may deviate from truth, as 
 vnr wills may deviate from virtue. You 
 will allow tliat it would be unjust and tyran- 
 nical to punish a man for unavoidable devi- 
 ations from truth. Where, then, is the 
 justice of condemning and punishing him for 
 the deviations of another faculty, which are 
 equally unavoidable ? 
 
 You say we are not to judge of this mat- 
 ter by reasons, but by the moral sense. 
 Will you forgive me, my Lord, to put you 
 in mind of a saying of Mr Hobbes, that 
 when reason is against a man he will be 
 against reason. I hope reason and the 
 moral sense are so good friends as not to 
 differ upon any point. But, to be serious, 
 1 agree with your Lordship, that it is the 
 moral sense that must judge of this point, 
 whether it be just to punish a man for doing 
 what it was not in his power not to do. 
 The very ideas or notions of just and un- 
 just are got by the moral sense ; as the 
 ideas of blue and red are got by the sense of 
 seeing. And as by the sense of seeing we de- 
 termine that this body is red, and thatisblue; 
 so, by the moral sense, we determine this 
 action tobejust,andthattobeunjust. Itisby 
 the moral sense that I determine, in general, 
 that it is unjust to require any duty of a man 
 which it is not in his power to perform. By 
 the same moral sense, in a particular case, I 
 determine a man to be guilty, upon finding 
 that he did the deed voluntarily and with 
 intention, without making any inquiry about 
 his power. Tlie way to reconcile these two 
 determinations I take to be this : — that, in 
 the last case, I take for granted the man's 
 power, because the common sense of man- 
 kind dictates, that what a man did volun- 
 tarily and with intention, he had power not 
 to do. 
 
 2. A second reason of my dissent is. 
 That the guilt of a bad action is diminished 
 in proportion as it is more difficult to resist 
 the motive. Suppose a man entrusted with 
 a secret, the betraying of which to the ene- 
 my may ruin an army. If he discloses it 
 for a bribe, however great, he is a villain 
 and a traitor, and deserves a thousand 
 deaths. But, if he falls into the enemy's 
 hands, and tlie secret be wrested from him 
 by the rack, our sentiments are greatly 
 ciianged; we do not charge him with vil- 
 laiiy, but with weakness. We liardly at all 
 blame a woman in such a case, because we 
 conceive torture, or the fear of present 
 death, to be a motive hardly resistible by 
 the weaker sex. 
 
 As it is, therefore, tlie uniform judgment 
 of mankind, that, where the deed is tlie 
 same, and the will and intention the same, 
 the degree of guilt must depend upon the 
 difficulty of resisting the motive, will it not 
 follow, that, when the motive is absolutely 
 irresistible, the guilt vanishes altogether ? 
 
 3. That this is the common sense of 
 mankind, appears further from the way in 
 which we treat madmen. They have will 
 and intention in what they do ; and, there- 
 fore, if no more is necessary to constitute a 
 crime, they ought to be found guilty of 
 crimes. Yet no man conceives that they 
 can be at all subjects of criminal law. For 
 what reason ? for this, in my opinion, that 
 they have not that power of self-command 
 which is necessary to make a man account- 
 able for his conduct. 
 
 You suppose, my Lord, a physical power 
 to forbear an action even when it is neces- 
 sary. But this I cannot grant. Indeed, 
 upon the system of free agency, I can easily 
 conceive a power which ia not exerted ; but, 
 upon the system of necessity, there can be 
 no such thing— every power that acts by 
 necessity must be exerted. 
 
 I do indeed think, that a man may act 
 without a motive ; and that, when the mo- 
 tives to action lie all on one side, he may 
 act in contradiction to them. But I a^ree 
 with your Lordship, that all such actions 
 are capricious ; and I apprehend that, if 
 there were no actions of this kind, there 
 could be no sucli thing as caprice, nor any 
 word in language to signify it : for why 
 should every language have a word to sig- 
 nify a thing which never did nor can exist ? 
 
 I agree also with your Lordship, that 
 there can be no merit in such an action, 
 even if it is innocent. But if it is vicious, 
 it has the highest degree of demerit ; for it 
 it is sinning without any temptation, and 
 serving the devil without any wages. It 
 ought to be observed, however, that a vir- 
 tuous action can never be capricious; because 
 there is always a just and sufficient motive 
 to it. For, if I have no other motive, I 
 must at least have this, that is a worthy 
 action, and is my duty ; which, in reason, 
 ought to weigh down all motives that can 
 be put into the opposite scale. A capricious 
 action may be innocent, and then it is 
 folly ; or it may be vicious, and then it is 
 pure wickedness. 
 
 Liberty, like all other good gifts of God, 
 may be abused. As civil liberty may be 
 abused to licentiousness, so our natural 
 liberty may be abused to caprice, folly, and 
 vice. But the proper exercise of liberty ia, 
 after weighing duly the motives on both sides, 
 to be determined, not by the strongest mo- 
 tive, but by that which has most authority. 
 
 It is of great importance in this matter, 
 to distinguish between the authority of mo- 
 tives and their force. The part that is 
 decent, that is manly, that is virtuous, that 
 is noble, has always authority upon its side. 
 Every man feels this authority in his own 
 breast ; and there are few men so wicked 
 as not to yield to it when it has no antago- 
 nist. 
 
 r «
 
 52 
 
 CORRESPONDENCE OF DR REID. 
 
 But pleasure, interest, passion, slotli, 
 often muster a great force on the other side, 
 which, though it has no authority, has often 
 the greater power ; and a conflict arises 
 between these opposite parties. Every 
 man is conscious of this conflict in liis own 
 breast, and is too often carried down by tlie 
 superior force of the party which he knows 
 to have no authority. 
 
 This is the conflict which Plato describes 
 between reason and appetite ; this is the 
 conflict which the New Testament describes 
 between the spirit and the flesh. The op- 
 posite parties, like Israel and Am.alek, dis- 
 pute the victory in the plain. When the 
 self-determining power, like Moses upon 
 the mount, lifts up its hand and exerts 
 itself, then Israel prevails, and virtue is 
 triumphant ; but when its hands hang down 
 and its vigour flags, then Amalek prevails. 
 I am, my dear Lord, most respectfully yours, 
 
 Tho. Reid. 
 
 II. 
 
 ON THE MATERIALISM OP PRIESTLEY AND 
 THE EGOISM OF FRENCH PHILOSOPHERS. 
 
 1775. 
 
 Dr Priestley, in his last 
 book, thinks that the power of perception, 
 as well as all the other powers that are 
 termed mental, is the result of such an 
 organical structure as that of the brain. 
 Consequently, saj's he, the whole man 
 becomes extinct at death, and we have no 
 hope of surviving the grave, but what is 
 derived fiom the light of Revelation. I 
 would be glad to know your Lordship's 
 opinion, whether, when my brain has lost 
 its original structure, and when, some hun- 
 dred years after, the same materials are 
 again fabricated so curiously as to become 
 an intelligent being, whether, I say, that 
 being will be mc ,•• or, if two or three such 
 beings should be formed out of my brain, 
 whether they will all be me, and conse- 
 quently all be one and the same intelligent 
 being. 
 
 This seems to me a great mystery, but 
 Priestley denies all mysteries. He thinks, 
 and rejoices in thinking so, that jjlants 
 have some degree of sensation. As to the 
 ■lower animals, they differ from us in degree 
 only, and not in kind. Only they have no 
 promise of a resurrection. If this be true, 
 why should not the King's advocate be 
 ordered to prosecute criminal brutes, and 
 
 " Our English / being of an ambiguous sound, it 
 would he convenient in psychology, could we occasion, 
 ally employ tne for a nominative, as the French do 
 their moi But this not being the case, Reid is here, 
 as elsewhere in his letters, grammatically at fault. 
 — H. 
 
 you criminal judges to try them ? You are 
 obliged to Dr Priestley for teaching you 
 one-half of your duty, of which you knew 
 nothing before. But I forgot that the 
 fault lies in the legislature, which has not 
 given you laws for this purpose. I hope, ho w- 
 ever, when any of them shall be brought to a 
 trial, that he will be allowed a. jury of his peer f:. 
 I am not much surprised that your 
 Lordship has found little entertainment in 
 a late French writer on human nature.* 
 From what I learn, they are all become 
 rank Epicureans. One would think that 
 French politesse might consort very well 
 with disinterested benevolence ; but, if we 
 believe themselves, it is all grimace. It is 
 flattery, in order to be flattered; like that 
 of the horse, who when his neck itches, 
 scratches his neighbour, that he may be 
 scratched by him again. I detest all sys- 
 tems that depreciate human nature. If it 
 be a delusion, that there is something in 
 the constitution of man that is venerable 
 and worthy of its author, let me live and 
 die in that delusion, rather than have my 
 eyes opened to see my species in a humi- 
 liating and disgusting light. Every good 
 man feels his indignation rise against those 
 who disparage his kindred or his conntry ; 
 why should it not rise against those who 
 disparage his kind 9 Were it not that we 
 sometimes see extremes meet, I should 
 think it very strange to see atheists and 
 high-shod divines contending as it were 
 who should most blacken and degrade human 
 nature. Yet I think the atheist acts the 
 more consistent part of the two : for surely 
 such views of human nature tend more to 
 promote atheism, than to promote religion 
 and virtue. .... . ■ 
 
 IIL 
 
 ON THE CONVERSION OF CLAY INTO 
 VEGETABLE MOULD. 
 
 October 1, 1775. 
 . . The theory of agriculture is 
 a wide and deep ocean, wlierein we soon go 
 beyond our depth. 
 
 I believe a lump of dry clay has much 
 the same degree of hardness, whether the 
 weather be hot or cold. It seems to be 
 more affected by moisture or drought : and 
 to be harder in dry weather, and more 
 easily broken when a little moistened. But 
 there is a degree of wetness in clay which 
 makes it not break at all when struck or 
 pressed ; it is compressed and changes its 
 figure, but does not break. 
 
 Clay ground, I think, ought to be ploughed 
 
 • Helvetius, Del'Esprit. — Lokd Woodhoi^sei.ef. 
 Hardly; this work tjeing then, nearly twenty years 
 old. Probably the work, " Sur rHoinme." — H.
 
 LETTERS TO LORD KAMES. 
 
 53 
 
 in the middle state between wetness and 
 dryness, for this reason : When too dry, 
 the plough cannot enter, or cannot make 
 handsome woi-k. Those clods are torn 
 up, which require great labour and ex- 
 pense to break them. And unless they 
 are broken, tlie roots of vegetables cannot 
 enter into them. When too wet, the fur- 
 row, in being raised and laid over by the 
 plough, is very luuch compressed, but not 
 broken. The compression makes it much 
 harder when it dries, than it would have 
 been without that compression. But when 
 the ground is neither too wet nor too dry, 
 the furrow, in being raised and laid over 
 by the plough, breaks or cracks with in- 
 numerable crevices, which admit air and 
 moisture, and the roots of vegetables. 
 
 Clay, when exposed in small parts to 
 the air, and to alternate moisture and 
 drought, mellows into mould. Thus a clod 
 of clay, which is so hard in seed-time that 
 you may stand upon it without breaking it, 
 ■will be found in autumn of the colour of 
 mould, and so softened, that when you 
 press it with the foot it crumbles to pieces. 
 On some clays this change is produced in a 
 shorter time, in the same circumstances ; 
 others are more refractory, and require 
 more time. 
 
 If wet clay is put into the fire uncom- 
 pressed, I am informed that it burns to 
 a.-^he.-, which make no bad manure. 
 
 But if the clay be wrought and compressed 
 when wet, and then dried, and then put 
 into the fire, it burns into brick, and with 
 a greater degree of heat, into a kind of 
 glass. 
 
 These, my Lord, are facts ; but to deduce 
 them from principles of attraction and re- 
 pulsion, is beyond the reach of my philo- 
 sophy : and I suspect there are many things 
 in agriculture, and many things in che- 
 mistry, that cannot be reduced to such 
 principles ; though Sir Isaac Newton seems 
 to iiave thought otherwise. 
 
 Human knowledge is like the steps of a 
 ladder. The first step consists of particular 
 truths, discovered by observation or expe- 
 riment: the second collects these into more 
 general truths : the third into still more 
 general. But there are many such steps 
 before we come to the top ; that is, to the 
 most general truths. Ambitious of know- 
 ledge, and unconscious of our own weak- 
 ness, we would fain jump at once from the 
 lowest step to the highest ; but the conse- 
 quence of this is, that we tumble down, 
 and find that our labour must be begun 
 sinew. Is not this a good picture of a phi- 
 losopher, my Lord ? I think so truly ; and 
 I should be vain of it, if I were not afraid 
 that I have stolen it from Lord Bacon. 
 I am, &c. 
 
 Tiin. Rkio. 
 
 IV. 
 
 ON THE GENERATION OF PLANTS AND 
 ANIMALS. 
 
 No date — but supposed 1775. 
 My Lord, — I have some compunction for 
 having been so tardy in answering the letter 
 which your Lordship did me the honour to 
 write me of the Cth November, especially 
 as it suggests two very curious subjects of 
 correspondence. But, indeed, my vacant 
 time has been so much filled up with trifles 
 of College business, and with the frequent 
 calls of a more numerous class of students 
 than I ever had before, that there was no 
 room for anything that could admit of 
 delay. 
 
 \'ou have expressed with great elegance 
 and strength the conjectui-e I hinted with 
 rCj^ard to the generation of plants. 
 
 I am indeed apt to conjecture, that both 
 plants and animals are at first organized 
 atoms, having all the parts of the animal 
 or i)lant, but so slender, and folded up in 
 such a manner, as to be reduced to a par- 
 ticle far beyond the reach of our senses, and 
 perhaps as small as the constituent parts 
 of water.* The earth, the water, and the 
 air may, for anything I know, be full of 
 such organized atoms. They may be no 
 more liable to hurt or injury, than the con- 
 stituent elementary parts of water or air. 
 They may serve the purposes of conmion 
 matter until they are brought into that 
 situation which nature has provided for 
 thrir unfolding themselves. When brought 
 into their proper matrix or womb, perhaps 
 after some previous preparations, tliey are 
 commonly surrounded with some fluid 
 matter, in which they unfold and stretch 
 themselves out to a length and breadth 
 perhaps some thousand times greater than 
 they had when folded up in the atom. 
 They would now be visible to the naked 
 eye, were it not that their limbs and vessels 
 are so slender that they cannot be distin- 
 guished from the fluid in which they float. 
 All is equally transparent, and therefore 
 neither figure nor colour can be discerned, 
 although the object has a considerable bulk. 
 The fcjetus now has a fluid circulating in its 
 vessels ; all the animal functions go on ; it 
 is nourished and grows ; and some parts, 
 first the heart, tl:en the head, then the 
 
 ♦ 'I'his O' ii'ioii is sini lar lo that ol M. Bonnet. 
 See his " Con idt rations siir lis tops Orpanizi«,'* 
 ami his '' ('ontcn:i)l (ion de la Nature" ( okd 
 WoiiiiiiDii I i.Ki-: — Riid's ()|)iiiion has eonipnralivi ly 
 little ri'scmlilai ICC- to the involution theory ot lloiinci : 
 it bears, how(\er, a strotig analoRV to the fnn^per- 
 mia of tlic Ionic philosopliers, more especially at 
 inodilicil l>y some of 1 he recent physiolojjical specii- 
 latisln of (icrinany 1 I is conjecture is curious, a* 
 a solitary escapade of our cautious philosopher in 
 the region (il iuaginatinn.— II.
 
 54 
 
 CORRESPONDENCE OF DR REID. 
 
 spine, by getting some colour, become 
 visible. 
 
 It is to be observed, that, from the time 
 that the heart first appears in the pellucid 
 liquor, until the time of birth, the animal 
 grows gradually and insensibly, as it does 
 after birth. But, before it is visible, it must 
 have uicreased in size many thousand times 
 in a few days. This does not look like 
 growth by nourishment, but like a sudden 
 unfolding of parts, which before were 
 wrapped up in a small atom. 
 
 I go along with your Lordship cordially, 
 till you come to the first formation of an 
 organized body. But there I hesitate. 
 "5lay there," say you, " not be particles 
 of a certain kind endowed with a power to 
 form in conjunction an organized body ?" 
 Would your Lordship allow that certain 
 letters might be endowed with the power 
 of forming themselves into an " Iliad" or 
 " ^neid," or even into a sensible discourse 
 in prose ?• I confess our faculties carry 
 us but a very little way in determining 
 what is possible and what is impossible, 
 and therefore we ought to be modest. But 
 I cannot help thinking that such a work 
 as the " Iliad," and much more an animal 
 or vegetable body, must have been made by 
 express design and counsel employed for 
 that end. And an author whom I very 
 much respect, has taught me, " That we 
 form this conclusion, not by any process of 
 reasoning, but by mere perception and feel- 
 ing, "-f And I think that conclusions formed 
 in this manner, are of all others most to 
 be trusted. It seems to me as easy to con- 
 trive a machine that should compose a 
 variety of epic poems and tragedies, as to 
 contrive laws of motion, by which unthink- 
 ing particles of matter should coalesce into 
 a variety of organized bodies. 
 
 " But," says your Lordship, " certainly 
 the Almighty has made none of his works 
 so imperfect as to stand in need of perpe- 
 tual miracles." Can we, my Lord, shew, 
 by any good reason, that the Almighty 
 finished his work at a stroke, and has con- 
 tinued ever since an unactive spectator ? 
 Can we prove that this method is the best ; 
 or that it is possible that the universe should 
 be well governed in this way ? I fear we 
 cannot. 
 
 And, if his continued operation be neces- 
 sary or proper, it is no miracle, while it 
 is uniform, and according to fixed laws. 
 Though we should suppose the gravitation 
 of matter to be the immediate operation of 
 the Deity, it would be no miracle, while it 
 is constant and uniform ; but if in that case 
 it should cease for a moment, only by his 
 
 • Thia illustration is borrowed from Cicero. (" De 
 Katura Deorum," 1. ii c. 37.)— H 
 
 + Lord Kames himself. " Essays on Morality," 
 «c.. Chapter " On the Idea of Power." 
 
 withholding his hand, thia would be a mi- 
 racle. 
 
 That an animal or vegetable body is a 
 work of art, and requires a skilful workman, 
 I think we may conclude, without going 
 beyond our sphere. But when we would 
 determine how it is formed, we have no 
 data; and our most rational conjectures are 
 only reveries, and probably wide of the 
 mark. We travel back to the first origin 
 of things on the wings of fancy. We would 
 discover Nature in puris naluralibus, and 
 trace her first operations and gradual pro- 
 gress. But, alas ! we soon find ourselves 
 unequal to the task : and perhaps this is 
 an entertainment reserved for us in a future 
 state. 
 
 As to what you say about earth or soil ; 
 there seems, indeed, to be a re))ulsion of the 
 parts, when it is enriched by the air, or by 
 manure. And, in consequence of this, it 
 swells and occupies more space. But, I 
 conceive, it gets an additional quantity of 
 matter, from the moisture and air which it 
 imbibes, and thereby increases both in bulk 
 and weight. I have been told that a dung- 
 hill made up of earth, dung, and lime, 
 trenched over two or three times, at proper 
 intervals, and then led out, will be found 
 to make more cart-loads than it received : 
 and I believe this to be true. If the earth 
 taken out of a pit does not fill it again, I 
 am apt to think there must have been va- 
 cuities in the earth at first, perhaps made 
 by the roots of plants that have decayed, 
 by moles, insects, or other causes. — I am, 
 my Lord, &c. 
 
 Tho. Reid. 
 
 ON THE LAWS OF MOTION. NEWTON S 
 
 AXIOMS AND DEFINITIONS. 
 
 Glasgow College, May 19, 1780. 
 
 My Lord, — In order to understand the 
 preliminary part of Newton's Principia, it 
 is necessary to attend to his general design, 
 both in his axioms and definitions. 
 
 First, As to his axioms : he sets down the 
 three laws of motion as axioms. But he 
 does not mean by this, that they are to be 
 held as self-evident truths ; nor does he in- 
 tend to prove tliem in what he says upon 
 them. They are incapable of demonstra- 
 tion, being matters of fact, which universally 
 obtain in the material world, and which had 
 before been observed by philosophers, and 
 verified by thousands of experiments by 
 Galileo, by Wren, Wallis, Huygens, and 
 Mariotte, to whom he refers for the proof 
 of them. Therefore, that he might not 
 actum agere, he lays them down as established 
 truths, saying some things upon them by
 
 LETTERS TO LORD KAMES. 
 
 55 
 
 way of illustration, and deducing some gene- 
 ral corollaries from them. 
 
 That this was his view, he expressly says 
 in the scholium following the axioms : 
 JIactenus principia Iradidi, a Miithematicis 
 recepla, et muUiplici cjrperientia confirmata, 
 ^c. The very same method he follows in 
 his optics, laying down as axioms what had 
 before been discovered in that science. 
 
 The axioms, or established principles in 
 the Principia, are three : — \U, Every body 
 perseveres in its present state, whether of 
 motion or rest, until it is made to change 
 that state by some force unpressed upon it. 
 2d, The change of motion produced is al- 
 ways proportional to the force impressed, 
 and in the direction of that force, id. All 
 action of bodies upon each other is mutual 
 or reciprocal, and in contrary directions ; 
 that is, if the body A produces any motion 
 or change of motion in B ; by the reaction 
 of B, an equal change of motion, but in a 
 contrary direction, will be produced in A. 
 This holds in all action of bodies on •each 
 other, whether by a stroke, by pressure, by 
 attraction, or by repulsion. 
 
 Perhaps, you will say these principles 
 ought not to be taken for granted, but to 
 be proved. True, my Lord, they ought to 
 be proved by a very copious induction of 
 experiments ; and, if they are not proved, 
 the whole system of the Principia falls to 
 the ground ; for it is all built upon them. 
 But Sir Isaac thought they were already 
 proved, and refers you to the authors by 
 whom. He never intended to prove them, 
 but to build upon them, as mathematicians 
 do upon the Elements of Euclid. 
 
 Secondly, As to the definitions. They 
 are intended to give accuracy and precision 
 to the terms he uses, in reasoning from the 
 laws of motion. The definitions are accom- 
 modated to the laws of motion, and fitted so 
 as to express with precision all reasoning 
 grounded upon the laws of motion. And, 
 for this reason, even the definitions will 
 appear obscure, if one has not a distinct 
 conception of the laws of motion always be- 
 fore his eye. 
 
 Taking for granted the laws of motion, 
 therefore, he gives the name of vis insiln, or 
 vis inertia, to that property of bodies, 
 whereby, according to the first and second 
 laws of motion, they persevere in their 
 Btiite, and resist any change, either from 
 rest to motion, or from motion to rest, 
 or from one degree or direction of motion 
 to another. 
 
 This vis insita is exercised in every case 
 wherein one body is made to change its 
 Btate by tiie action of another boiiy ; and 
 the exertion of it may, in difVercnt respects, 
 be called Ijolh resistani'C and impetus. 
 
 The reluctance whicrh tli<! body // has to 
 change its state, which can be overcome 
 
 only by a force proportioned to that reluct- 
 ance, is resistance. The reaction of th»* 
 body A upon B, which, accorduig to th 
 third law of motion, is equal to the action ot 
 B upon ^, and in a contrary direction, is 
 impetus. 
 
 Thus, in every change made in the state 
 of one body by another, there is mutual 
 resistance and mutual impetus. The one 
 never exists without the other. A body at 
 rest not only resists, but gives an impetus to 
 the body that strikes it. And a body in 
 motion coming against a body at rest, not 
 only gives an impetus to the body that was 
 at rest, but resists that change of its own 
 motion which is produced by the stroke. 
 Each gives an impetus to the other, and 
 exerts a resistance to the impetus it receives 
 from the other. 
 
 This is the notion which Newton affixes 
 to the words — impetus and resistance ; and, 
 I think, it corresponds perfectly with the 
 third law of motion, but may appear dark if 
 that is not kept in view. 
 
 But, because this notion of resistance and 
 impetus differs somewhat from the vulgar 
 application of those words, in order to point 
 out the difference, he contrasts it with the 
 vulgar meaning in the words which your 
 Lordship quotes: — Valgus resistentiam 
 quiescenlibus et impelum moventibnstrihuiti 
 sed motus et quies, ut rulgo concipiuntur, 
 respectu solo dislingniintur, ncque semper 
 vere quiescunt qucevulgo tanqunm quiescentia 
 spectantur. He considers both resistance 
 and impetus as belonging to every body, in 
 every case in which it is made to change its 
 state, whether from rest to motion, or from 
 motion to rest. It resists the change of its 
 own state, and, by its reaction, gives an 
 impetus to tlie body that acts upon it. The 
 vulgar, having no notion, or no distinct 
 notion, of this reaction established by the 
 third law of motion, suit their language to 
 their conceptions. He suits his to the laws 
 of motion. 
 
 A post, you say, resists, but has no im- 
 petus. This is true in the vulgar sense of 
 the word. But, in order to sliew you that 
 his sense dilfers somewhat from the vulgar, 
 he would say, that the post has impetus in 
 his sense. And by this he means only, that 
 the post stops, or changes the motion of the 
 body that strikes it ; and, in producing this 
 change, exerts a force equal to that with 
 which it was struck, but in a contrary 
 direction. This is a necessary consdiuence 
 of the third law of motion. The vulgar 
 both speak and judge of motion and rest in 
 a body, by its situation with respect to some 
 other body, wliich, i)crha])s, from prejudice, 
 tiicy C(jnceive to lie at i-fst. This makes 
 Newton say, " 'IMiat motion and rest, as 
 conimonly conciivcd, are distinguisliiid by 
 lelation ; nor are those bodies always really
 
 56 
 
 CORRESPONDENCE OF DR REII). 
 
 at rest which are commonly conceived to 
 be at rest." 
 
 Rest, when we speak of bodies, is opposed, 
 not to self-motion only, but to all change of 
 place. Absolute, or real rest, is opposed to 
 real motion ; and relative rest— that is, rest 
 with relation to such a body tliat is supposed 
 at rest, is opposed to relative motion with 
 respect to the same body. But a body may 
 be relatively at rest, and, at the same time, 
 really in motion. Thus, a house rests upon 
 its foundation for ages ; but this rest is 
 relative with respect to the earth. For it 
 has gone round the eartli's axis every day, 
 and round the sun every year. 
 
 The distinction your Lordship makes be- 
 tween moving and being moved, belongs not 
 to physics, but to metaphysics. In physics, 
 you may use the active or the passive verb 
 as you like best. The reason is, that in 
 physics we seek not the efficient causes of 
 phenomena, but* only the rules or laws by 
 which they are regulated. We know, tliat 
 a body once put in motion, continues to 
 move, or, if you please, to be moved, until 
 some force is applied to stop or retard it. 
 But, whether this phenomenon is produced 
 by some real activity in the body itself, or 
 by the efficiency of some external cause ; 
 or whether it requires no efficiency at all to 
 continue in the state into which it is put, is, 
 perhaps, difficult to determine; and is a 
 question that belongs not to physics, but to 
 metaphysics. 
 
 Some divines and philosophers have 
 maintained, tliat the preservation of a 
 created being in existence, is a continued 
 act of creation ; and that annihilation is 
 nothing but the suspending that exertion of 
 the Creator by which t!ie being was upheld 
 in existence. 
 
 Analogous to this, I think, is the opinion, 
 that the continuance of motion in a bodv 
 requires a continued exertion of that active 
 force which put it into the state of motion. 
 I am rather inclined to the contrary of botli 
 these opinions, and disposed to think that 
 continuance of existence, and continuance 
 of motion in a body, requires no active 
 cause ; and that it is only a change of state, 
 and not a continuance of the present state, 
 that requires active power. But, I suspect, 
 both questions are rather beyond the reacli 
 of the human faculties. However, they 
 belong not to the province of physics, but 
 to that of metaphysics. 
 
 I wish I may be intelligible, and that I 
 do not oppress your Lordship with the gar- 
 rulity of old age. I find myself, indeed, 
 growing old, and have no right to plead ex- 
 emption from the infirmities of that stage of 
 life. For that reason, I have made choice 
 of an assistant in my office. Yesterday, the 
 college, at my desire, made choice of Mr 
 Archibald Arthur, preacher, to be my assist- 
 
 ant and successor.* I think I have done 
 good service to the college by this, and pro- 
 cured some leisure to myself, though with a 
 reduction of my finances. May your Lord- 
 ship Uve long and happy Yours, 
 
 Tho. Reid. 
 
 VL 
 
 ON CONJECTURES AND HYPOTHESES IN PHI- 
 LOSOPHY CAUSE WHAT IN RELATION 
 
 TO PHYSICS. — DIFFERENT PROVINCES OF 
 PHYSICAL AND OF METAPHYSICAL SCIENCE. 
 
 \Gth December 1780. 
 
 My Lord, — 1. I am now to answer the 
 letter you honoured me with of 7th No- 
 vember. And, first, I disclaim what you 
 seem to impute to me — to wit, " the valuing 
 myself upon my ignorance of the cause of 
 gravity." To confess ignorance when one 
 is conscious of it, I take to be a sign, not 
 of pride, but of humility, and of that can- 
 dour which becomes a philosopher ; and so 
 I meant it. 
 
 2. Your Lordship thinks, " That never 
 to trust to hypotheses and conjectures about 
 the works of God, and being persuaded that 
 they are more like to be false than true, is 
 a discouraging doctrine, and damps the 
 spirit of inquiry," &c. JSow, my Lord, I 
 liave, ever since I was acquainted with 
 B.'.con and Newton, thouglit that this doc- 
 trine is tlie very key to natural philosophy, 
 and the touchstone by which everything 
 that is legitimate and solid in that science, 
 is to be distinguished from what is spurious 
 and hollow ; and I can hardly think, that 
 we can differ in so capital a point, if we 
 understood each other's meaning. 
 
 3. I would discourage no man from con- 
 jecturing, only I wish him not to take his 
 conjectures for knowledge, or to expect that 
 others should do so. Conjecturing may be 
 a useful step even in natural philosophy. 
 Thus, atteniling to sucli a phenomenon, I 
 conjecture that it may be owing to such a 
 cause. This may lead me to make the ex- 
 periments or observations proper for dis- 
 covering whether that is really the cause or 
 not: and if I can discover, either that it 
 is or is not, my knowledge is improved; 
 and my conjecture was a step to that im- 
 
 * Mr Arthur, a man of learning, abilities, and 
 worth, filled the Chair of Moral Ph losi'pliy in the 
 University of Glasgow for filtrcn ye.irs, wilh a repu. 
 tatioii which did not disappoint the hopes of his 
 respectaule predecessor. A volume of " Discourse? 
 on Theological and Literary Subjects," which give a 
 very favourable idea of his talents, the justness of 
 his taste, and the rectiiude of his moral and relij:;ious 
 principles, has t)eeii published, since his death, by 
 Professor Richardson ot the same coilcgc — a gentle, 
 man distinguished m the literary world, and who has 
 done honour to the memory of his friend, by .in inter- 
 esting sketch of his life and character, subjoined to 
 these discourses — I.ORU WooDiioiJsKLEt.
 
 LETTERS TO LORD KAMES. 
 
 67 
 
 yroveiuent. But, while I rest in my con- 
 jecture, my judgment remains in suspense, 
 and all I can say is, it may be so, and it 
 may be otherwise. 
 
 4. A cause that is conjectured ought to 
 be such, that, if it really does exist, it will 
 produce the effect. If it have not this 
 quality, it hardly deserves the name of a 
 conjecture. Supposing it to have this 
 quality, the question remains — Whether 
 does it exist or not ? And this, being a 
 question of fact, is to be tried by positive 
 evidence. Thus, Des Cartes conjectured, 
 that the planets are carried round the sun 
 in a vortex of subtile matter. The cause 
 here assigned is sufficient to produce the 
 effect. It may, therefore, be entitled to 
 the name of a conjecture. But where is 
 the evidence of the existence of such a vor- 
 tex ? If there be no evidence for it, even 
 though there were none against it, it is a 
 conjecture only, and ought to have no 
 admittance into chaste natural philosophy. 
 
 5. All investigation of what we call the 
 causes of natural phenomena may be reduced 
 to this syllogism — If such a cause exists, it 
 will produce such a phenomenon : but that 
 cause does exist : Therefore, &c. The first 
 proposition is merely hypothetical. And a 
 man in his closet, without consulting nature, 
 may make a thousand such propositions, 
 and connect them into a system ; but this 
 is only a system of hypotheses, conjectures, 
 or theories ; and there cannot be one con- 
 clusion in natural philosophy drawn from it, 
 until he consults nature, and discovers 
 whether the causes he has conjectured 
 do really exist. As far as he can shew that 
 they do, he makes a real progress in the 
 knowledge of nature, and not a step further. 
 I hope in all tliis your Lordship will agree 
 with me. But it remains to be considered 
 how the second proposition of the syllogism 
 is to be proved — to wit, that such a cause 
 does really exist. Will nothing satisfy 
 here but demonstration ? 
 
 (j. I am so far from thinking so, my Lord, 
 that I am persuaded we never can have 
 demonstration in tills case. All that we 
 know of the material woi-ld, mustbegrounded 
 on the testimony of our senses. Our senses 
 testify particular facts only : from these we 
 collect, by induction, general facts, which 
 we cull laws of nature, or natural causes. 
 Thus, ascending by a just and cautious in- 
 duction, from what is less to what is more 
 general, we discover, as far as we are able, 
 natural causes, or laws of nature. This is 
 the analytical jtart of natural pliilosophy. 
 The synthetical part takes for granted, as 
 j)rinciples, the causes discovered by induc- 
 tion, anil from these explains or accounts 
 for tjie ])hciiomeiia which result from them. 
 This analysis and synthesis make \ip tlie 
 whole theory of natni'al pliiiosopliy. 'I"he 
 
 practical part consists in applying the laws 
 of nature to produce effects useful in life. 
 
 7. From this view of natural philosophy, 
 which I have learned from Newton, your 
 Lordship will perceive that no man who 
 understands it will pretend to demon- 
 strate any of its prim iples. Nay, the most 
 certain and best established of them may, 
 for anjthuig we know, admit of exceptions. 
 For instance, tin re is no principle in natu- 
 ral philosophy better established than the 
 universal gravitation of matter. But, can 
 this be demonstrated ? By no means. 
 What is the evidence of it, then ? It is 
 collected by induction, partly from our 
 daily experience, and from the experience 
 of all nations, in ail ages, in all places of 
 earth, sea, and air, which we can reach ; 
 and partly from the observations and expe- 
 riments of philosophers, which shew that 
 even air and smoke, and every body upon 
 w-hich experiments have been made, gravi- 
 tate precisely in proportion to the quantity 
 of matter ; that the sea and earth gravitate 
 towards the moon, and the moon towards 
 them ; that the planets and comets gravi- 
 tate towards the sun, and towards one 
 another, and the sun towards them. This 
 is the sum of evidence ; and it is as difl'er- 
 ent from demonstration, on the one hand, 
 as from conjecture on the other. It is the 
 same kind of evidence which we have, that 
 tire will burn and water drown, that bread will 
 nourish and arsenic poison, which, I think, 
 would not properly be called conjecture. 
 
 8. It is proper here to explain what is 
 meant by the cause of a phenomenon, when 
 that word is used in natural philosophy. 
 The word cause is so ambiguous, that I fear 
 many mistake its meaning, and take it to 
 mean the efficient cause, which I think it 
 never does in tliis science. 
 
 y. By the cause of a phenomenon, nothing 
 is meant but the law of nature, of which 
 that phenomenon is an uistance, or a neces- 
 sary consequence. The cause of a body's 
 falling to the ground is its gravity. But 
 gra\'ity is not an efficient cause, but a gene- 
 ral law, that obtains in nature, of which 
 law the fall of this body is a particular in- 
 stance. The cause why a body projected 
 moves in a parabola, is, that this motion is 
 the necessary consequence of the projectile 
 force and gravity united. But these are 
 not efficient causes ; they are only laws of 
 nature. In natural iihilosophy, therefore, 
 we seek only the general laws, according to 
 which nature works, and these we call the 
 causes of what is done according to them. 
 But such laws cannot be the efficient cause 
 of anytlnlig. 'J'liey are only the rule accc)rd- 
 ing to which the efficient cause operates. 
 
 10. A natural iihilosophcr may search 
 after the cause of .a law of nature ; but 
 this means no more than siarching for a
 
 58 
 
 CORRESPONDENCE OF DR REID. 
 
 more general law, which includes that par- 
 ticular law, and perhaps many others under 
 it. This was all that Newton aimed at by 
 his ether. He thought it possible, that, if 
 there was such an ether, the gravitation of 
 bodies, the reflection and refraction of the 
 rays of light, and many other laws of nature, 
 might be the necessary consequences of the 
 elasticity and repelling force of the ether. 
 But, supposing this ether to exist, its elas- 
 ticity and repelling force must be considered 
 as a law of nature ; and the efficient cause 
 of this elasticity would still have been latent 
 11. Efficient causes, properly so called, 
 are not within the sphere of natural philo- 
 sophy. Its business is, from particular 
 facts in the material world, to collect, by 
 just induction, the laws that are general, 
 and from these the more general, as far as 
 we can go. And when this is done, natural 
 philosophy has no more to do. It exhibits 
 to our view the grand machine of the mate- 
 rial world, analysed, as it were, and taken 
 to pieces, with the connexious and depend- 
 encies of its several parts, and the laws of 
 its several movements. It belongs to 
 another branch of philosophy to consider 
 whether this machine is the work of chance 
 or of design, and whether of good or of bad 
 design ; whether there is not an intelligent 
 first Mover who contrived the whole, and 
 gives motion to the whole, according to the 
 laws which the natural philosopher has dis- 
 covered, or, perhaps, according to laws 
 still more general, of which we can only 
 discover some branches ; and whether he 
 does these things by his own hand, so to 
 speak, or employs subordinate efficient 
 causes to execute his purposes. These are 
 very noble and important inquiries, but they 
 do not belong to natural philosophy ; nor 
 can we proceed in them in the way of ex- 
 periment and induction, the only instru- 
 ments the natural philosopher uses in his 
 researches. 
 
 12. Whether you call this branch of 
 philosophy Natural Theology or Meta- 
 physics, I care not ; but I think it ought 
 not to be confounded with Natural Philo- 
 sophy ; and neither of them with Mathe- 
 matics. Let the mathematician demon- 
 strate the relation of abstract quantity ; the 
 natural philosopher investigate the laws of 
 the material system by induction ; and the 
 metaphysician, the final causes, and the 
 efficient causes of what we see and what 
 natural philosophy discovers in the world 
 we live in. 
 
 13. As to final causes, they stare us in 
 the face wherever we cast our eyes. I can 
 no more doubt whether the eye was made 
 for the purpose of seeing, and the ear of 
 hearing, than I can doubt of a mathema- 
 tical axiom ; yet the evidence is neither 
 mathematical demonstration, nor is it in- 
 
 duction. In a word, final causes, good final 
 causes, are seen plainly everywhere : in the 
 heavens and in the earth ; in the constitu- 
 tion of every animal, and in our own consti- 
 tution of body and of mind ; and they are 
 most worthy of observation, and have a 
 charm in them that delights the soul. 
 
 14. As to Efficient Causes, I am afraid 
 our faculties carry us but a very little way, 
 and almost only to general conclusions. I 
 hold it to be self-evident, that every pro- 
 duction, and every change in nature, must 
 have an efficient cause that has power 
 to produce the effect ; and that an effect 
 which has the most manifest marks of in- 
 telligence, wisdom, and goodness, must have 
 an intelligent, wise, and good efficient cause. 
 From these, and some such self-evident 
 truths, we may discover the principles of 
 natural theology, and that the Deity is the 
 first efficient cause of all nature. But how 
 far he operates in nature immediately, or 
 how far by the mmistry of subordinate effi- 
 cient causes, to which he has given power 
 adequate to the task committed to them, I 
 am afraid our reason is not able to discover, 
 and we can do little else than conjecture. 
 We are led by nature to believe ourselves 
 to be the efficient causes of our own volun- 
 tary actions ; and, from analogy, we judge 
 the same of other intelligent beings. But 
 with regard to the works of nature, I can- 
 not recollect a single instance wherein I can 
 say, with any degree of assurance, that such 
 a thing is the efficient cause of such a phe- 
 nomenon of nature. 
 
 15. Malebranche, and many of the Car- 
 tesians, ascribed all to the immediate oper- 
 ation of the Deity, except the determinations 
 of the will of free agents. Leilmitz, and all 
 his followers, maintain, that God finished 
 his work at the creation, having endowed 
 every creature and every individual particle 
 of matter, with such internal powers as 
 necessarily produce all its actions, motions, 
 and changes, to the end of time. Others 
 have held, that various intelligent beings, 
 appointed by the Deity to their several 
 departments, are the efficient causes of the 
 various operations of nature. Others, that 
 there are beings endowed with power with- 
 out intelligence, which are the efficient 
 causes in nature's operations ; and they 
 have given them the name of Plastic 
 Powers, or Plastic Natures. A late author 
 of your Lordship's acquaintance," has given 
 it as ancient metaphysics. That every body 
 in the universe is compounded of two sub- 
 stances united— to wit, an immaterial mind 
 or soul, which, in the inanimate creation, 
 has the power of motion without thought ; 
 and of inert matter as the other part. Tiie 
 celebrated Dr Priestley maintains, that 
 
 • Lord Monboddo. — H.
 
 LETTERS TO LORD KAMES. 
 
 o9 
 
 matter, properly organized, has not only the 
 power of motion, but of thought and intel- 
 ligence ; and that a man is only a piece of 
 matter properly organized. 
 
 16. Of all these systems about the effi- 
 cient causes of the phenomena of nature, 
 there is not one that, in my opinion, can be 
 either proved or refuted from the principles 
 of natural philosophy. They belong to 
 metaphysics, and affect not natural philo- 
 sophy, whether they be true or false. Some 
 of them, I thinli, may be refuted upon meta- 
 physical principles ; but, as to the others, I 
 can neither see such evidence for them or 
 against them as determines my belief. 
 They seem to me to be conjectures only 
 about matters where we have not evidence ; 
 and, therefore, I must confess my ignor- 
 ance. 
 
 17. As to the point which gave occasion 
 to this long detail. Whether there is reason 
 to think that matter gravitates by an in- 
 herent power, and is the efficient cause of 
 its own gravitation, I say, first. This is a 
 metaphysical question, which concerns not 
 natural philosophy, and can neither be 
 proved nor refuted by any principle in that 
 science. Natural philosophy informs us, 
 tluit matter gravitates according to a certain 
 law ; and it says no more. Whether mat- 
 ter be active or passive in gravitation, can- 
 not be determined by any experiment I can 
 think of. If it should be said that we ought 
 to conclude it to be active, because we per- 
 ceive no externiil cause of its gravitation, 
 this argument, I fear, will go too far. Be- 
 sides it is very weak, amounting only to 
 this : I do not perceive such a thing, there- 
 fore it does not exist. 
 
 Hi. I never could see good reason to 
 believe that matter has any active power at 
 all. And, indeed, if it were evident that it 
 has o)ie,\ think there could be no good reason 
 assigned for not allowing it o/hers. Your 
 Lordship sjieaks of the power of resisting 
 motion, and some others, as acknowledged 
 active powers inherent in matter. As to 
 the resistance to motion, and the continu- 
 ance in motion, I never could satisfy my- 
 self wliether tliese are not the necessary 
 consequences of matter being inactive. If 
 they imply activity, that may lie in some 
 other cause. 
 
 10. I am not able to form any distinct 
 conception of active power but such as I find 
 in myself. I can only exert my active 
 power by will, wliich supposes thought. It 
 seems to me, that, if I was not conscious of 
 activity in myself, I could never, from things 
 I see about me, have had tlie conception or 
 idea of active power. 1 see a succession of 
 dianges, but I i-ee not tlie power, that is, 
 the efficient cause of them ; but, having got 
 the notion of active jiower, from the con- 
 eciousnesB of my own activity, and finding 
 
 it a first principle, that every production 
 requires active power, I can reason about 
 an active power of that kind I am acquainted 
 with — that is, such as supposes thought and 
 choice, and is exerted by will. But, if there 
 is anything in an unthinking inanimate being 
 that can be called active power, I know not 
 what it is, and cannot reason about it. 
 
 20. If you conceive that the activity of 
 matter is directed by thought and will in 
 matter, every particle of matter must know 
 the situation and distance of every other 
 particle within the planetary system ; but 
 this, I am apt to think, is not your Lord- 
 ship's opinion. 
 
 21. I must therefore conclude, that this 
 active power is guided in all its operations 
 by some intelligent Being, who knows both 
 the law of gravitation, and the distance and 
 situation of every particle of matter with 
 regard to every other particle, in all the 
 changes that happen in the material world. 
 I can only conceive two ways in which this 
 particle of matter can be guided, in all the 
 exertions of its active power, by an intelli- 
 gent Being. Either it was formed, in its 
 creation, upon a foreknowledge of all the 
 situations it shall ever be in with respect to 
 other particles, and had such an internal 
 structure given it, as necessarily produces, 
 in succession, all the motions, and tend- 
 encies to motion, it shall ever exert. This 
 would make every particle of matter a ma- 
 chine or automaton, and every particle of a 
 different structure from every other particle 
 in the universe. This is indeed the opinion 
 of Leibnitz ; but I am not prejudiced against 
 it upon that account ; I only wished to know 
 whether your Lordship adopted it or not. 
 Another way, and the only other way, in 
 which I can conceive the active power of a 
 particle of matter, guided by an intelligent 
 Being, is by a continual influence exerted 
 according to its situation and the situation 
 of other particles. In this case, the particle 
 would be guided as a horse is by his rider ; 
 and I think it would be improper to ascribe 
 to it the power of gravitation. It has only 
 the power of obeying its guide. Whether 
 your Lordshi]) chooses the first or the last 
 in this alternative, I should be glad to 
 know ; or whether you can think of a third 
 way better than either. 
 
 22. I will not add to the length of so 
 immoderately long a letter by criticising 
 ujion the passages you quote from Newton. 
 I have a great reg;ii-d for his judgment ; but 
 where he diflers from me, I think him 
 wrong. 
 
 The idea of natural philosojihy I have 
 given in this letter, 1 think 1 hail from him. 
 Li' m scholia and ciueries he gives a range to 
 his thoughts, and sometimes enters the 
 regions of natural theology and metapliysics, 
 this I think is very allowable, and is not to
 
 60 
 
 CORRESPONDENCE OF DR REID. 
 
 be considered a part of his physics, which 
 are contained in his propositions and coroU 
 hiries. Even his queries and conjectures 
 are valuable ; but 1 thinl{ he never intended 
 that they should be taken for granted, but 
 made the subject of inc^uiry. 
 
 Tho. REin. 
 
 VII. 
 
 LAWS OF MOTION — PRESSURE OF FLUIDS. 
 
 Januiiry 25, I?!!!. 
 
 My Lord, — To what cause is it owing 
 that I differ so much from your Lordshij) 
 in Physics, when we differ so little in Meta- 
 physics ? I am at a loss to account for this 
 phenomenon. Whether is it owing to our 
 having different conceptions to the same 
 words ? — or, as I rather think it is, to 
 your being dissatisfied with the three gene- 
 ral laws of motion ? Without them I know 
 not indeed how to reason in physics. Ar- 
 chimedes reasoned from them both in me- 
 chanics and hydrostatics. Galileo, Huy- 
 gens, Wren, Wallis, Mariotte, and many 
 others, reasoned from them, without ob- 
 serving that they did so. 
 
 I have not indeed any scruples about the 
 principles of hydrostatics. They seem to 
 me to be the necessary consequences of the 
 definition of a fluid, the three laws of motion, 
 and the law of gravitation ; and, therefore, 
 I cannot assent to your Lordship's reason- 
 ing, either about the pressure of fluids, or 
 about the suspension of the mercury in the 
 barometer. 
 
 As to the first, the experiments which shew 
 that fluids do, in fact, press uiidtquaque, 
 are so numerous, and so well known to your 
 Lordshij), that I apprehend it is not the fact 
 you question, but the cause. You think 
 that gravity is not the cause. Why ? Be- 
 cause gravity gives to every part of the fluid 
 a tendency downwards only ; and what Ls 
 true of every part, is true of the whole : 
 therefore, the whole has no other tendency 
 but downward. This argument is specious, 
 but there is a fallacy in it. If the parts did 
 not act u])on one another, and counteract 
 one another, the argument would be good ; 
 but the parts are so connected, that one 
 cannot go down but another must go up, 
 and, therefore, that very gravity which 
 presses down one part presses up another : 
 so that every part is pressed down by its 
 own gravity, and pressed up, at the same 
 time, by the gravity of other parts ; and 
 the contrary pressures being equal, it re- 
 mains at rest. 
 
 This may be illustrated by a balance 
 equilibrating by equal weights in both scales. 
 I say each arm of the balance is equally 
 pressed upwards and downwards at the same 
 
 time, and from that cause is at rest ; although 
 the tendency of the weights, m each of the 
 scales, is downwards only. I prove it a pus- 
 feiiori ; because the arm of a balance being 
 moveable by the least force, if it was pressed 
 in one direction only, it would move in that 
 direction : but it does not move. I prove 
 it a priori ; because the necessary effect of 
 pressing one arm down, is the pressing the 
 other up with the same force : therefore, 
 each arm is pressed down by the weight in 
 its own scale, and equally pressed up by the 
 weight in the other scale ; and, being pressed 
 with equal force in contrary directions, it 
 remains at rest. Your Lordship will easily 
 apply this reasoning to a fluid, every part of 
 wliich is as moveable as the balance is about 
 its fnlcnim ; and no one part can move, but 
 an equal part must be moved in a contrary 
 direction. And I think it is impossible we 
 should differ in this, but in words. 
 
 Next, as to the barometer. You say the 
 mercury is kept up by the expansive power 
 of the air : but you say further, that it is 
 not kept up by the weight of the air. I 
 agree to the first, but not to the last. The 
 expansive power of the air is owing to its 
 being compressed ; and it is compressed by 
 the weight of the incumbent atmosphere. 
 Its expansive force is exactly equal to the 
 force that presses and condenses it ; and 
 that force is the weight of the air above it, 
 to the top of the a/mo.sjihere — so that the ex- 
 pansive force of the air is the c lu.m proximo, 
 the weight of the atmosphere the causa 
 remota of the suspension of the mercury. 
 Your Lordship knows the maxim, Causa 
 cnuscB est causa causati. The barometer, 
 therefore, while it measures the expansive 
 force of the air which presses upon the 
 lower end of the tube, at the same time 
 measures the weight of the atmosphere, 
 which is the cause of that expansive force, 
 and exactly equal to it. If the air was not 
 pressed by the incumbent weight, it would 
 expand in boundless space, until it liad no 
 more expansive force. 
 
 As to the observation in the postscript, 
 it is true, that the gravity of the air, while 
 it rests upon an unyielding bottom, will give 
 no motion to it ; but the mercury in the 
 lower end of the tube yields to the pressure 
 of the air upon it, until the weight of the 
 mercury is balanced by the pressure of the 
 air. 
 
 What your Lordship is pleased to call the 
 Opus Mufjuum, goes on, but more slowly 
 tlian I wish — I am, most respectfuilj-, my 
 Lord, yours, 
 
 Tho. Rkid.
 
 LETTERS TO LORD KAMES. 
 
 61 
 
 VIIL 
 
 ON THE ACCELERATED MOTION OF FALLING 
 BODIES. 
 
 Glasgow College, Nov. 11, 1782. 
 
 My Lord, — My hope that your Lordship 
 is in no worse state of health than when I 
 left you, and that the rest of the good family 
 are well, is confirmed by your continuing 
 your favourite speculations. I promised to 
 call upon you in the morning before I came 
 away. I sent in Samuel to see if you was 
 awake : he reported that you w-as sleeping 
 sound ; and I could not fiud it in my heart 
 to disturb your repose. 
 
 When we say, that, in falling bodies, the 
 space gone through is as the square of the 
 velocity, it must be carefully observed that 
 the velocity meant in this proposition, is the 
 last velocity, which the body acquires only 
 the last moment of its fall : but the space 
 meant is the whole space gone through, 
 from the beginning of its fall to the end. 
 
 As this is the meaning of the proposition, 
 your Lordship will easily perceive, that the 
 velocity of the last moment must indeed 
 correspond to the space gone through iu 
 that moment, but cannot correspond to the 
 space gonethroughin anyprecedingmoment, 
 with a less velocity ; and, consequently, can- 
 not correspond to the whole space gone 
 through in the last and all preceding mo- 
 ments taken together. You say very justly, 
 that, whether the motion be equable or 
 accelerated, the space gone through in any 
 instant of time corresponds to the velocity 
 in that instant. But it does not follow from 
 this, that, in accelerated motion, the space 
 gone through in many succeeding instants 
 will correspond to the velocity of the last 
 instant. 
 
 If any writer in physics has pretended to 
 demonstrate mathematically this proposi- 
 tion — that a body falling by gravity in vacuo, 
 goes through a space which is as the square 
 of its last velocity ; he umst be one who 
 writes without distinct conceptions, of which 
 kind we have not a few. 
 
 TJie proposition is not mathematical, but 
 physical. It admits not of demonstration, 
 as your Lordship justly observes, but of 
 proof by experiment, or rea-soning grounded 
 on experiment. There is, however, a ma- 
 thematical proposition, which possibly an 
 
 inaccurate writer might confound with the 
 last mentioned. It is this — that a body 
 uniformly accelerated from a state of rest, 
 will go through a space which is as the 
 square of the last velocity. * This is an ab- 
 stract proposition, and has been mathema- 
 tically demonstrated ; and it may be made 
 a step in the proof of the physical proposi- 
 tion. But the proof must be completed by 
 shewing, that, in fact, bodies desceiuhng by 
 gravitation are uniformly accelerated. This 
 is sometimes shewn by a machine invented 
 by S'Gravesande, to measure the velocities 
 of falling bodies ; sometimes it is proved 
 by the experiments upon pendulums ; and 
 sometimes we deduce it by reasoning from 
 the second law of motion, which we think 
 is grounded on universal experience. So 
 that the proof of the physical proposition 
 always rests ultimately upon experience, and 
 not solely upon mathematical demonstra- 
 tion. — I am, my Lord, respectfulh yours, 
 
 Tho. Reid. 
 
 IX. 
 
 EXTRACT OF A LETTER TO MRS DRl'MMOND, 
 AFTER THE DEATH OF HER HUSBAND, 
 LORD KAMES, IN 1782. 
 
 I accept, dear madam, the present you 
 sent me,* as a testimony of your regard, 
 and as a precious relic of a man whose 
 talents I admired and whose virtues I 
 honoured ; a man who honoured me with 
 a share of his conversation, and of his cor- 
 respondence, which is my pride, and which 
 gaveme the best opportunity of knowing 
 his real worth. 
 
 I have lost in him one of the greatest 
 comforts of my life; but his remembrauce 
 will alwaj's be dear to me, and demand my 
 best wishes and prayers for those whom he 
 has left behind him. 
 
 When thne has abated your just grief 
 for the loss of such a husband, the recol- 
 lection of his eminent talents, and of his 
 public and domestic virtues, will pour balm 
 into the wouiid. Friends are not lost who 
 leave such a character behind them, and 
 such an example to those who come after 
 them. 
 
 A gold snuffbox.
 
 62 
 
 CORRESPONDENCE OF DR REID. 
 
 C— LETTERS TO DR JAMES GREGORY. 
 
 Glasgou College, April 1, 1783. 
 Dear Sir, — By favour of Mr Patrick 
 Wilson, our Assistant Professor of Astro- 
 nomy, I send you two more numbers of my 
 lucubrations.* I am not sure when I can 
 send more, as I am not sure whether my 
 scribe may soon leave the College. 
 
 I shall be much obliged to you if you will 
 continue to favour me with your observa- 
 tions, though I have put off examining those 
 you have sent until the MSS. be returned, 
 which I expect about the end of this month, 
 along with Dug. Stewart's observations. I 
 have also sent the Genealogy of the Gre- 
 gories, which your brother left with me : 
 I suspected that it was more particular than 
 the copy I had, but I find they agree per- 
 fectly. 
 
 You will please deliver it to him, with 
 my compliments. The few days he was 
 here he payed his respects to all the Pro- 
 fessors and all his acquaintance, and they , 
 are all very much pleased with his appear- 
 ance. If it please God to spare his life, I 
 hope he will do honour to his Alma Mater, 
 and to his friends.+ 
 
 I know not upon what authority the 
 Edinburgh and London news-writei-s have 
 given contradictory accounts of Dr Hun- 
 ter's settlements.^: There is nothing cer- 
 tainly known here. I know that, six or 
 seven years ago, he made a settlement very 
 favourable to this College. But whether 
 this is altered, or in what respect, I believe 
 nobody here knows. But we shall probably 
 know soon. He was surely a man that did 
 great honour to his country, and I doubt 
 not but his publick spirit, which I take to 
 have been great, will have disposed him to 
 leave his books, medals, and other literary 
 furniture — which he had collected at vast 
 expense, and with great industry — in such 
 a way as that it may be useful to the pub- 
 lick. 
 
 I beg you to make my best respects to 
 Mrs Gregory, and to all your family ; and 
 I am, dear Sir, 
 
 Your most obedient Servant, 
 
 Tho. Reid. 
 
 » His " Essays on ihe Intellectual Powers." — H. 
 
 t This was the Rev. William Gregory, A. M. of 
 Balliol College, Oxford, afterwards Kcctor of St 
 Mary's, Bentham, and one of the Preachers of Can. 
 terbury Cathedral. He had studied at Glasgow pre. 
 viously to entering at Oxford. — H, 
 
 t The celebrated Dr Wm. Hunter. He bequeathed 
 his anatomical preparations, library,, and collection 
 of medals, to the University of Glasgow, and a sum 
 of money for the erection of a museum. — H. 
 
 11. 
 
 Glasgow College, June 8, 1783. 
 
 Dear Sir, 
 
 I cannot get 
 more copied of my papers till next winter, 
 nnd indeed have not much more ready. 
 I'his parcel goes to page G58. I believe 
 what you have got before may be one-half 
 or more of all I intend. The materials of 
 what is not yet ready for the copyer are 
 partly discourses read in our Literary So- 
 ciety, partly notes of my Lectures. 
 
 Your judgment of what you have seen 
 flatters me very much, and adds greatly to 
 my own opinion of it, though authors sel- 
 dom are deficient in a good opinion of their 
 own works. 
 
 I am at a loss to express my obligations 
 to you for the pains you have taken, and pro- 
 pose to take agam upon it. I have carefully 
 laid up the observations you sent me, to be 
 considered when the copy they refer to is 
 returned, and I hope for the continuation of 
 them. The analogy between memory and 
 prescience is, I believe, a notion of my own. 
 But I shall be open to conviction on this 
 and every thing else we may diff'er about. 
 
 I have often thought of what you propose 
 — to give the History of the Ideal System ; 
 and what I have to say against it, by itself, 
 and I am far from being positive that it 
 stands in the most proper place. Perhaps 
 it will be easier to judge of this when the 
 work is concluded. I have endeavoured to 
 put it in separate chapters, whose titles may 
 direct those who have no taste for it to pass 
 over them. But I hope to have your opi- 
 nion upon this point at more length when 
 we meet. I observe that Boyle and others, 
 who, at the Reformation of Natural Philo- 
 sophy, gave new Unlit, found it necessary to 
 contrast their discoveries with the Aristo- 
 telian notions which then prevailed. We 
 could now wish their works purged of the 
 controversial part ; but, perhaps, it was pro- 
 per and necessary at the time they wrote, 
 when men's minds were full of the old sys- 
 tems, and prepossessed in its favour. What 
 I take to be the genuine philosophy of the 
 human mind, is in so low a state, and has 
 so many enemies, that, I apprehend those 
 who would make any improvement in it 
 must, for some time at least, build with one 
 hand, and hold a weapon with the other. 
 
 I shall be very glad to see you here, and 
 will take it as a favour if you acquaint me 
 when you have fixed your time, that I may 
 be sure to be at home. I beg you will
 
 LETTERS TO DIl JAMES GREGORY 
 
 63 
 
 make my best compliments to Mrs Gregory, 
 whom I should be happy to see along with 
 you iu good health, and to Mr D. Gordon, 
 if he is still with you, and to all your fa- 
 mily ; and am, dear sir, 
 
 Yours most affectionately, 
 Tho. Reid. 
 
 III. 
 
 March 14, 1784. 
 
 Dear Sir, — I send you now the remainder 
 of what I propose to print with respect to 
 the Intellectual Powers of tlie Mind. It 
 may, perhaps, be a year before what relates 
 to the Active Powers be ready, and, there- 
 fore, I think the former might be published 
 by itself, as it is very uncertain whether I 
 shall live to publish the latter. 
 
 I have enclosed, in the first of the three 
 papers now sent, the contents of the whole, 
 which you was so good as to write out as 
 far as it was carried last year. I think the 
 title may be, Essnyxonthelntellectual Powers 
 of the Human A/ind. It will easily divide 
 into eight essays, as you will see by the 
 contents ; but with regard to this, as well 
 as whether the two parts may be published 
 separately, I wish to have your advice and 
 Mr Stuart's — ('V'c.) Since you have been so 
 good as to take a concern in it, I apprehend 
 that the second Part — I mean what relates to 
 the Active Powers — will not be near so largo 
 as the first. I wish to have the manuscript, 
 with your remarks and Mr Stuart's, (vc,) 
 about the end of April, if you can. Dr 
 Rose at Cliiswick — who, you know, has all 
 along had a principal concern in The 
 Monlh/i/ lirriew — has made me a very kind 
 offer, that, if I please to send the MSS. to 
 him, he will both give me his remarks, and 
 treat with a bookseller about the sale of it. 
 I think this is an offer that I ought not to re- 
 fuse ; and I can have a good occasion of 
 sending it about the beginning of the month 
 of May, by his son, who is at this college. 
 I long to hear how Mrs Gregory has stood 
 this severe winter, and beg my most huml>le 
 respects to her, and to the Rev. Mr Wil- 
 liam, when you write him. 
 
 I send you on the other page an anecdote 
 respecting Sir I. Newton," which I do not 
 remember whether I ever happened to men- 
 tion to you in conversation. If his descent 
 be not clearly ascertained, (as I think it is 
 not in the books I have seen,) might it not 
 be worth while for the antitjuarian branch 
 of your R. Society, to inquire if they 
 can finrl evidence to confirm the account 
 wliich he is said to have given of himself. 
 Sheriff Cross was very zealous about it, 
 
 • See Brcwuter'ii " Life of Newton," .mtl, inf,-n, 
 Itcid's later to Mr Roljikoii, at the end of his Cor- 
 Ti'iiKimlcricc.— .H. 
 
 when death put a stop to his inquiries. — I 
 am, dear Sir, yours most respectfully, 
 
 Tho. Reid. 
 
 When I lived in Old Aberdeen, above 
 twenty years ago, I happened to be con- 
 versing over a pipe of tobacco, with a gen- 
 tleman of that coimtry, who had been lately 
 at Edinburgh. He told me that he had 
 been often hi company with Mr Hepburn 
 of Kehh, with whom I had the honour of 
 some acquaintance. He said that, speaking 
 of Sir Isaac Newton, Mr Hepburn men- 
 tioned an anecdote, which he had from Mr 
 James Gregory, Professor of Mathematics 
 at Edinburgh, which was to this purpose : — 
 Mr Gregory being at London for some time 
 after he resigned the mathematical chair, 
 was often with Sir I, Newton. One day 
 Sir Isaac said to him, " Gregory, I believe 
 you don't know that I am connected with 
 Scotland." " Pray, how. Sir Isaac ?" said 
 Gregory. Sir Isaac said — " He was told, 
 that his grandfather was a gentleman of 
 East Lothian ; that he came to London with 
 King James at his accession to the Crown 
 of England, and there spent his fortune, as 
 many more did at that time, by which his 
 son (Sir Isaac's father) was reduced to mean 
 circumstances." To this Gregory bluntly 
 replied — " Newton, a gentleman in East 
 Lothian ? — I never heard of a gentleman of 
 East Lothian of that name." Upon this 
 Sir Isaac said, that, being very young when 
 his father died, he had it only by tradition, 
 and it might be a mistake ; and imme- 
 diately turned the conversation to another 
 subject. 
 
 I confess I suspected that the gentleman 
 who was my author had given some colour- 
 ing to this story ; and, therefore, I never 
 mentioned it for a good many years. 
 
 After I removed to Glasgow, I came to 
 be very intimately acquainted with Mr 
 Cross, the Sheriff" of Laiierick, and one day 
 at his own house mentioned this story with- 
 out naming my author, of whom I expressed 
 some diffidence. The Sheriff immediately 
 took it up as a matter worth being inquired 
 into. He said he was well acquainted with 
 Mr Hepburn of Keith, (who was then 
 alive,) and tliat he would write him, to 
 know whether he ever heard Mr Gregory 
 say that he had such a conversation with 
 Sir Isaac Newton. He said, he knew that 
 Mr Keith, the ambassador, was also inti- 
 mate with Mr Gregory, and that he would 
 write him to the same purpose. Some time 
 after, Mr Cross told me, that he had 
 answers from botli the gentlemen above- 
 mentioned, and that both remembered to 
 have heard Mr CJregory mention the con- 
 versation between him and Sir Isaac New- 
 ton to the purpose above narrated ; and at 
 tile same time acknowledged that they liad
 
 6-1 
 
 CORRESPONDENCE OF DR REID. 
 
 made uo farther inquiry about the mat- 
 ter. 
 
 Mr Cross, however, continued in the 
 inquiry ; and, a sliort time before his death, 
 told me, that all lie had learned was, that 
 there is, or was lately, a baronet's family 
 of the name of Newton in West-Lothian, 
 or Mid-Lothian, (I have forgot which;) 
 that there is a tradition in that family that 
 Sir Isaac Newton wrote a letter to the old 
 knight that was, (I think Sir John New- 
 ton of Newton was his name,) desiring 
 to know what children, and particularly what 
 sons he had ; their age, and what profes- 
 sions they intended. That tlie old baronet 
 never deigned to return an answer to this 
 letter, which his family was sorry for, as 
 they thought Sir Isaac might have intended 
 to do something for them. 
 
 IV. 
 
 Dear Sir, — Happening to have gone into 
 the country a little way, your letter of 5th 
 June did not reach me in time to write you 
 before you set out upon your journey, which 
 I wish to be attended with much happiness 
 to the parties, and comfort to their friends. * 
 
 I was so stupid at first as to misunder- 
 stand the direction you gave me how to 
 write you. Now I see it is plain enough, 
 and I hope have taken it right. I send you 
 the enclosed to Dr Rose, as you desire. 
 
 I have by me our friend D. Stewart's 
 " Discourse on the Ideas of Cause and 
 Effect," &c. ; and I have this day sent him 
 my remarks upon it. I am happy to find 
 his sentiments on that subject agree so 
 much witli my own. I think it well wrote, 
 and hope it will be very useful. 
 
 Dr Rose will shew you the letter I wrote 
 to him along with the MSS., and one from 
 Mr Bell-f- to me, which I enclosed in it : 
 these contain all the information I have to 
 give, and all the instructions I thought 
 necessary. I expect an answer from one 
 quarter, at least, before the work be cold from 
 the press. But the only answer that shall 
 ever have any reply from me must be one 
 who keeps good temper, and who observes 
 good manners, in the first place ; and next 
 one wjio, in my opinion, gives new light to 
 the subject. 
 
 I wish you happy success in your own 
 affairs, and a safe return. If nothing hap- 
 pens of which you wish to acquaint me 
 sooner, I shall be glad to hear from you on 
 your return ; being, dear sir. 
 
 Most affectionately yours, 
 
 Tho. Reid. 
 
 Glasgow Coll. 1784. 
 
 • This alludes to the marriage of Dr Gregory's 
 eldest sister lo the licv. Archibald Alison. — H. 
 f Tlie pul)lislicr — H. 
 
 [ The letter quoted above by Mr Stewart, 
 {p. 34) " /o one of Dr Iieid\s most hitimnte 
 friends,'''' was ar/t/ressed to Dr James Greyory 
 on the death <f his first wife, and should 
 properly here find its place H.] 
 
 V. 
 
 ON THE MEANING OF NOTION. 
 
 Glasgow College, December 31, 1784. 
 
 Dear Sir, — I had the favour of yours by 
 Mr Tower, and take the opportunity of his 
 return to wish you many happy returns of 
 this season. 
 
 I believe you and I cannot differ about 
 right or wrong notions, but in words. 
 
 The notions we have of real existences, 
 may with good reason be said to be right oi 
 wrong, true or false ; but I think every 
 notion of this kind has a standard to which 
 I believe my notion to agree ; and as that 
 belief is true or false, so my notion of the 
 thing is true or false. For instance, if my 
 notion of the Devil includes horns and cloven 
 feet, I must believe these to be attributes 
 of the Devil, otherwise they would not b« 
 included in my notion of him. If this be. 
 lief be wrong, I have a wrong notion of him ; 
 and, as soon as I am convinced that this 
 belief is wrong, I leave out these attributes 
 in my notion of him. 
 
 I may have an abstract notion of a being 
 with horns and cloven feet, without apply- 
 ing it to any individual — then it is a simple 
 apju-ehension, and neither true nor false ; 
 but it cannot be my notion of any indivi- 
 dual that exists, unless I believe that being 
 to have these attributes. I am therefore 
 still apt to think that true and fitlse can only 
 with proprieiy be applied to notions which 
 include some belief; but whether my re- 
 mark on your use of the word notion be just 
 or not, I cannot presently say : you will 
 judge for yourself. 
 
 I thought to have seen D. Stewart here 
 about this time. When you see him, please 
 acquaint him that I have made my remarks 
 upon the performance he left with me. I 
 am extremely obliged to you and him for 
 correcting the sheets of my performance. 
 You leave me very little to do. 
 
 By the slowness of printing, I conjecture 
 that the book cannot be published next 
 spring, and can only be ready for the spring 
 1786. I desired long ago to know of Mr 
 Bell whether he proposed to publish it in 
 one vol. or two ; but I have not had an 
 answer. I suspect it will be too thick for 
 one vol. and too thin for two. Perhaps if 
 the publication is delayed to 1786, 1 might 
 have my Essays on the Active Powers 
 ready, of which Mr Bell shall have the first 
 offer ; and I apprehend that, with this
 
 LETTERS TO DR JAMES GREGORY. 
 
 05 
 
 addition, there may be two sizeable 4tos in 
 the whole. — I am, dear Sir, 
 
 Yours most affectionately, 
 
 TiK). Reid. 
 
 VI. 
 
 Dear Sir, — I send you enclosed what I 
 propose as the title-page of my essays, with 
 an epistle, whicli, I hope, you and Mr 
 Stewart will please to allow me to prefix to 
 them. 
 
 Whether your name should go first, on 
 account of your doctor's degree, or Mr 
 Stewart's, on account of his seniority as a 
 professor, I leave you to adjust between 
 yourselves.* 
 
 As to the title-page, you and he may 
 alter what you think fit,+ and deliver it to 
 Mr Bell without farther communication 
 with me, as he intends immediately to ad- 
 vertise the book. 
 
 If you find anything in the epistle that 
 you would have altered or corrected, you 
 may please write me ; but you need not 
 send back the copy, as I have a copy by me. 
 
 I know not how to express my obliga- 
 tions to you and Mr Stewart for the aid 
 you have given me. — I am, dear Sir, your 
 most obliged servant, 
 
 Tho. Reid. 
 May 2d, 1785, 
 
 Glasgow College. 
 
 You will give the epistle to the printers 
 when it is wanted. I send with this the 
 hist part of the MS. 
 
 VII. 
 
 MEANIN^ OF CAUSE — MOTIVE — LAW OF 
 NATURE. 
 
 June 14, 178'). 
 Dear Sir, — I am extremely obliged to 
 you for your friendly consultation about my 
 health. For two days past, I have had 
 almost nothing of my ailment, which I 
 ascribe to some exercise I have taken, and 
 to a comfortable warmness in the air. I 
 resolve to try some short excursions, which 
 I can make either on foot or in a chaise. 
 If that do not produce the efiect, I shall 
 fall to your prescriptions, which I think 
 very rational. I very probably may be at 
 home when you propose to be in Glasgow. 
 
 • In thf? MS. deiicatixn of Ihe " f.ssays on the 
 Intellectual Powers," I)r Gregory's name 6t;indg 
 belore that of Mr Stewart 'J'his order was, prohably 
 by Dr Gretory liimstlf, reversed There are, also 
 iiiire viTli.il mprovetnenis ill the style of the dedica. 
 tion, a< It ttJiicln piiiiteri, which, it is likely, were 
 iDitoilticcd 1 y l)r Gregory or Mr Stcw.irt, — II. 
 
 t 'I'he title sctit wai, " Ksaays on the Inlellcclual 
 I'owcr.', (jf the Huinaii Mind," or, " ICssays on Ihe 
 IiittlltCtual I'owerr of Man." 'Ihe latter was pre- 
 ferred — H. 
 
 Your speculation to demonstrate, mathe- 
 matically, the difi'erence between the rela- 
 tion of motive and action, and the relation of 
 cause and effect,* is, indeed, so new to me, 
 that Icannoteasilyformajudgmentabout it. 
 I shall offer some of my thougiits on the sub- 
 ject of those two relations. Whether they be 
 favourable to your speculation, or unfavour- 
 able, I cannot immediately determine. 
 
 The word cause, is very ambiguous in all 
 languages. I have wrote a chapter lately 
 upon the causes of this ambiguity. The 
 words power, agent, effect, have a hke am- 
 biguity ; each different meaning of the first 
 mentioned word leading to a corresponding 
 meaning of the three last. A reason, an 
 end, an instrument, and even a motive, is 
 often called a cause. You certainly exclude 
 the last from what you call a cause. 
 Whether you exclude all the other meanings 
 which I think improper meanings, I am not 
 so sure. 
 
 In the strict and proper sense, I take an 
 efficient cause to be a being who had power 
 to produce the effect, and exerted that power 
 for that purpose. 
 
 Active power is a quality which can only 
 be in a substance that really exists, and is 
 endowed with that power. Power to pro- 
 duce an effect, supposes power not to pro- 
 duce it ; otherwise it is not power but neces- 
 sity, which is incompatible with power 
 taken in a strict sense. The exertion of that 
 power, is agency, or efficiency. That every 
 event must have a cause in this proper sense, 
 I take to be self-evident. 
 
 I should have noticed that I am not able 
 to form a conception how power, in the strict 
 sense, can be exerted without will ; nor can 
 there be will without some degree of under- 
 standing. Therefore, nothing can be an 
 efficient cause, in the proper sense, but an 
 intelligent being. 
 
 I believe we get the first conception of 
 power, in the proper sense, from the con- 
 sciousness of our o\\ n exertions ; and, as all 
 our power is exerted by will, we cannot form 
 a conception how power can be exerted with- 
 out will. Hent;e the only notion we can 
 form of Almighty power in the Deity, is that 
 
 ♦This refers to Dr Gregory's ingenious" Essay on Ihe 
 Differeiicebetween thcKtlationof Motiveand .Action, 
 and that of Cause and Kffect in I'hysics ; on phvsic.il 
 And mathematical principles." This 'reatisi', whitb 
 was pulilishcd in i'i9-?, had been previously coinmiu 
 nicated to various philosophical friends, ai d in p,ir> 
 ticuiar to every Necessitarian of the auihor's ac. 
 quainance, with the assurance th.n, if any error 
 could be pointed out in the reatoinng — which, as 
 mathematical, could be examined with the utmost 
 rigour — the ohjection should either be complete y 
 answered, or the essay itaelf suppressed. Duly one 
 Necessitarian, however, allowed his objections to he 
 published ; :in<l these, with Dr Gregory's answcrf, are 
 to be loniid in the iippeiiiiix to the essay. Dr Heid 
 was anicing the first to whom Dr Gregory com- 
 municated this work; and to Dr Ueid, when ptit>. 
 lUhed, the '• Thildsophical .ind Literary E«»iy»" 
 were inscribed. — H. 
 
 V
 
 <B6 
 
 CORRESPONDENCE OF DR REID. 
 
 he can do whatever he wills A power to do 
 what he does not will, is words without a 
 meaning- 
 Matter cannot be the cause of anything ; 
 it can only be an instrument in the hands of 
 a real cause. Thus, when a body has a cer- 
 tain force given it by impulse, it may com- 
 municate that force to another body, and 
 that to a third, and so on- But, when we 
 trace back this motion to its origin, it must 
 nave been given, not by matter, but by some 
 being which had in itself the power of be- 
 ginning motion — that is, by a proper efficient 
 cause of motion. 
 
 It cannot be said that there is a constant 
 conjunction between a proper cause and the 
 effect ; for, though the effect cannot be, 
 without power to produce it, yet that power 
 may be, without being exerted, and power 
 which is not exerted produces no effect. 
 
 You will see, by what is said above, 
 what I take to be the strict and proper 
 meaning of the word cause, and the related 
 words, power, w/enf, ^-c. In this sense we 
 use it in reasoning concerning the being and 
 attributes of the Deity. In this sense we 
 ought to use it in the question about liberty 
 and necessity, and, I think, in all metaphy- 
 sical reasoning about causes and effects; 
 for when, in metaphysical reasoning, we de- 
 part from this sense, the word is so vague 
 that there can be no clear reasoning about 
 
 It. 
 
 Suppose, now, that you take the word 
 cause in this strict sense ; its relation to its 
 effect is so self- evidently different from the 
 relation of a motive to an action, that I am 
 jealous of a mathematical demonstration of 
 a truth so self-evident. Nothing is more 
 difficult than to demonstrate what i- self- 
 evident. A cause is a being which has a 
 real existence ; a motive has no real exist- 
 ence, and, therefore, can have no active 
 power. It is a thing conceived, and not a 
 ■thing that exists ; and, therefore, can neither 
 be active nor even passive. To say that a 
 motive really acts, is as absurd as to say 
 that a motive drinks my health, or that a 
 motive gives me a box on the ear. 
 ■ In physics, the word cause has another 
 meaning, which, though I think it an im- 
 proper one, yet is distinct, and, therefore, 
 may be reasoned upon. When a phenome- 
 non is produced according to a certain law 
 of nature, we call the law of nature the cause 
 of that phenomenon ; and to the laws of 
 nature we accordingly ascribe power, agency, 
 efficiency. The whole business of physics 
 is to discover, by observation and experi- 
 ment, the laws of nature, and to apply them 
 to the solution of the phenomena : this we 
 call discovering the causes of things. But 
 this, however common, is an improper sense 
 of the word cause, 
 
 A law of nature can no more be an agent 
 
 than can a motive. It is a thing conceived, 
 and not a thing that exists ; and, therefore, 
 can neither act, nor be acted upon. A l-aw 
 of nature is a purpose or resolution of the 
 author of nature, to act according to a cer- 
 tain rule — either immediately by himself or 
 by instruments that are under his direction. 
 There must be a real agent to produce the 
 phenomenon according to the law. A 
 malefactor is not hanged by the law, but 
 according to the law, by the executioner. 
 
 I suspect you use the word cause in this 
 sense for a law of nature, according to which 
 a phenomenon is produced. If so, it should 
 appear distinctly that you do so. 
 
 But is it not self-evident, that the rela- 
 tion between a law of nature and the event 
 which is produced according to it, is very 
 different from the relation between a motive 
 and the action to which it is a motive ? Is 
 there any need of demonstration for this ? 
 or does it admit of demonstration ? 
 
 There is, indeed, a supposition upon which 
 the two relations would be very similar. 
 The supposition is, that, by a law of nature, 
 the influence of motives upon actions is as 
 invariable as is the effect of impulse upon 
 matter ; but to suppose this is to suppose 
 fatality and not to prove it. 
 
 It is a question of fact, whether the in- 
 fluence of motives be fixed bylaws of nature, 
 so that they shall always have the same 
 effect in the same circumstances. Upon 
 this, indeed, the question about liberty and 
 necessity hangs. But I have never seen 
 any proof that there are such laws of nature, 
 iar less any proof that the strongest motive 
 always prevails- However much our late 
 fatalists have boasted of this principle as of 
 a law of nature, without ever telling us what 
 they mean by the strongest motive. I am 
 persuaded that, whenever they shall be 
 pleased to give us any measure of the 
 strength of motives distinct from their pre- 
 valence, it will appear, from experience, 
 that the strongest motive does not always 
 prevail. If no other test or measure of the 
 strength of motives can be found but their 
 prevailing, then this boasted principle will 
 be only an identical proposition, and signify 
 only that the strongest motive is the strong- 
 est motive, and the motive that prevails is 
 the motive that prevails — which proves 
 nothing. 
 
 May it not be objected to your reasoning, 
 that you apply the three lav/s of motion to 
 motives ; but motives may be subject to 
 other laws of nature, no less invariable than 
 the laws of motion, though not the same. 
 Different parts of nature have different 
 laws, it may be said ; and to apply the laws 
 of one part to another part, particularly to 
 apply the laws of inert matter to the phe- 
 nomena of mind, may lead into great falla- 
 cies. I think, indeed, that your reasoning
 
 LETTERS TO DR JAMES GREGORY. 
 
 67 
 
 proves, that, between the influence of mo- 
 tives upon a mind and the influence of 
 impulse upon a body, there is but a very 
 slight analogy, which fails in many in- 
 stances. 
 
 I have wearied you and myself with a 
 long detail, I fear, little to the purpose ; but 
 it was in my head, and so came out. I am 
 just setting out on a jaunt to Paisley, with 
 ray wife, son-in-law, and daughter, to come 
 home at night. 
 
 • • • • 
 
 Yours most affectionately, 
 
 Tho. Reid. 
 
 VIII. 
 
 MEANING OF CAUSE. 
 
 Dear Sir, — I believe 1 have never an- 
 swered the letter you favoured me with of 
 Aug. 9, by Capt. Gallic. First, I obeyed 
 your commands in attending Mrs Siddons 
 twice, in " Douglas," and in " Venice Pre- 
 served." I believe I should have had much 
 more pleasure if, on account of deafness, I 
 liad not lost much of what she said, and had 
 been better acquainted with the pLays. But 
 I believe she is really an admirable actress, 
 and deserves the admiration you express of 
 her. 
 
 You say, you fear we shall never agree 
 with respect to the notion of cause and 
 effect. I am at a loss to know wherein we 
 differ. I think we agree in this, that a 
 cause, in the proper and strict sense, (which, 
 I think, we may call the metaphysical sense,) 
 signifies a being or mind that ha.s power 
 and will to produce the effect. But there 
 is another meaning of the word cause, which 
 is so well authorized by custom, that we 
 cannot always avoid using it, and I think 
 we may call it the physical sense ; as wlien 
 we say that heat is the cause that turns 
 water into vapour, and cold the cause that 
 freezes it into ice. A cause, in this sense, 
 means only something which, by the laws 
 of nature, the effect always follows. I 
 think natural philosophers, when they pre- 
 tend to shew the causes of natural phenom- 
 ena, always use the word in this last sense; 
 and the vulgar in common discourse very 
 often do tlie same. 
 
 The reason why I take no notice of neuter 
 verbs is, that I conceive they are used to 
 express an event, without any signification 
 of its having a cause or not. But I .shall 
 be very glad to .see your speculations upon 
 this subject when tln,'y are ready. 
 
 I had a letter from Dr Price lately, 
 thanking me for a copy of the Essays I 
 ordered to lie presented to him, which he 
 has read, and calls it a work of the first 
 value ; commends me particularly for treat- 
 
 ing his friend Dr Priestly so gently, who, 
 he says, had been unhappily led to use me 
 ill 
 
 As you are so kind as to ask about my 
 distemper, I think it is almost quite gone, 
 so as to give me no uneasiness. I abstain 
 from fruit and malt liquor, and take a little 
 port wine, morning, noon, and night, not 
 above two bottles in a week when alone. 
 The more I walk, or ride, or even talk or 
 read audibly, I am the better. 
 
 When your time is fixed for coming here, 
 I shall be glad to know it. — I am, dear Sir, 
 Most affectionately yours, 
 Tho. Reid. 
 
 Glasgow, 23^ Sept. 1785. 
 
 IX. 
 
 ON CAUSE AND EFFECT — MOTIVE AND ACTION. 
 
 [March 1786.] 
 
 Dear Sir, — I hope your essay, along 
 with this, wiU come to your hand by the 
 carrier, and within the time you mention. 
 It would have been sent sooner if I had not 
 had a discourse to deliver before our Lite- 
 rary Society last Friday. 
 
 You give me most agreeable intelligence — 
 first, of Mrs Stewart's being so far recovered 
 of a dangerous illness, and then of my 
 friend William's promotion, who, I hope, 
 will wear the robe with decency and dignity. 
 
 Your essay I have read several times 
 with attention, and I think the reasoning 
 perfectly conclusive to prove that the rela- 
 tion between motives and actions is totally 
 of a different kind from that which physical 
 causes bear to their effects. 
 
 I agree with you that the hypothesis you 
 combat in this essay is more unreasonable 
 than that of constant conjunction. Not 
 because it is more reasonable to conceive a 
 constant conjunction between motives and 
 actions than an occasional one ; but be- 
 cause the first agrees better than the last 
 with the hypothesis of motives being physi- 
 cal causes of actions. Between a physical 
 cause and its effect, the conjunction must 
 be constant, unless in the case of a miracle, 
 or suspension of the laws of nature. Wh.at 
 D. Hume says of causes, in general, is very 
 just when applied to ])hysical causes, that a 
 constant conjunction with the effect is essen- 
 tial to such causes, and implied in the very 
 conception of them. 
 
 The style of this essay is more simple 
 than that of the last, and, I think, on that 
 account, more proper for a philosophical 
 dissertation. 
 
 I am proud of the approbation you ex- 
 press of the essays :* I have made some 
 
 * On tho Active Poweri.— H. 
 
 F y
 
 68 
 
 CORRESPONDENCE OF DR REID. 
 
 correctious and additions, but such as I 
 Jiope will not make it necessary to write it 
 over again. But I wish, if I find health 
 and leisure, in summer, to add some essays 
 to go before that on liberty, in order to give 
 some farther elucidation to the principles 
 of morals, both theoretical and practical. I 
 expect your remarks and D. Stewart's upon 
 what is in hand. It will be no inconveni- 
 ence to wait for them two or three, or even 
 four months — I am, dear Sir, 
 
 Yours most affectionately, 
 
 Tho. Reid. 
 
 Dear Sir, — In answer to your queries,* 
 
 • The follnwing may serve to explain the allusions 
 in the-e letters, ami, in general, the connection of 
 Reid with the family of Gregory :— 
 
 The Reverend John Gregory of Driimoak, in the 
 county of Aberdeen, was the common ancestor of 
 two lines, both greatly distinguished for matliema. 
 tical ami general ability. His wife was a daughter 
 of David Anderson of Finzaugh, cousin-gerraan of 
 the celebrated analyst, Alexaniler Anderson, the 
 fiiend and follower of Vieta. By her, he had two 
 jons, David and James, progenitors of the several 
 lines. 
 
 I. LI^E. 
 
 The elder son, Dnv/d Gregory of Kinairdy, in the 
 county of Aberdeen, was bred a merch iiit, and lived 
 the greater part of a long life in Holland He had 
 the singular fortime of seeing three sons Professors of 
 Mathom.itics at the same time in three British uni- 
 versities. 
 
 Of those sons, tbe eldest, David, (born 16'ifi, rii d 
 1710,) though inferior to his uncle James in inventive 
 genius, was one ol the n ost ilhistrious geometers and 
 genmitrical authors of his time. In I68'J, elected 
 Professor of Mathematics in the University of Fdin. 
 burgh, he was, in lfi91, by the influence of Newton 
 nominated Savilian Professor of Astronomy in Ox- 
 ford. His son, Z)(7r/;V/, who died 1767, was student, 
 canon, and de n of Christ Church, and Regius Pro. 
 fes-or of Modern History in ihe >ame university. 
 
 The second of these -oiis, James, succeeded his 
 brother David as t'rofe-sor of Ma' hematics in Edin. 
 burgh, and retired in favour of the celebrated Wac- 
 laurin, in I7<?5. 
 
 1 he third srin, Charlfs, was Professor of Mathema. 
 tics in St Andrews from I7ii7 to I":i9, whtn he resigned 
 in favour of his son, Uavid, who held the Chair until 
 his di ath in 176 t. 
 
 Dr Rdd's mother was a daughter of David Gre- 
 gory of Kinairdy, aiid sister of the three Mathema- 
 tical Professors. 
 
 II. t,IV7. 
 
 Jamet, the younger son of the Rev. John Gregory, 
 was born in 16'38, and died at the early age of thirty- 
 seven. He was Professor of Mathematics at St And. 
 rew's and Edinburgh ; inventor of the ReHectir:g or 
 Gregorian Telescope ; author of several remarkalile 
 treatisis on optics and geometry ; and, altogether, 
 one of the roost original mathematicians of his age. 
 
 His son, ./w2<;s, Professor of Medicine in King's 
 College, Aberdeen, was father of a more celebrated 
 son — 
 
 John, who was born 1724, and died 177.3. He was 
 sue essively I'roleasor of Philosojiliy and of Medicine 
 ill Kins'.- CiHegp, Ali-rdecn, and of the Practice of 
 Physic in <he University of Kdmburgh ; author of 
 the ■' Compafative View oi the Siate and Faculties o( 
 Mun and Animals," of ihe * I.ectU'Cs on Ih^ Duties 
 and Qiialiticatioiis of a Physici m," of" Elcmi'iits of 
 the Practice 'f hysic," and of " A Fathe's leg icy 
 to his Daujjhters" His eldest son (Dr Keid's cor. 
 resp n'ent)— 
 
 Jamet, wns born 1753, and died 18<;i. He was 
 Professor of the Theory, afterwards of the Practice, 
 
 I know not precisely either the year of my 
 grandfather's death or his age. But all 
 that I have heard agrees very well with the 
 account you mention. He served appren- 
 tice to a merchant in Rotterdam or Catnp- 
 vere, and, I believe, continued there till the 
 murder of his elder brother. After he came 
 home, he prosecuted the murderer, (son 
 and heir to Viscount Frendritt, as I have 
 heard, though I find not the title among the 
 extinct or forfeited Peers,) who, being a 
 Roman Catholic, was protected by all the 
 interest of the Duke of York ; but was at 
 last condemned, but pardoned by the crown, 
 and soon after killed in a naval engage- 
 ment." Your g-grandfather was so nmch 
 younger tlinn Kinairdy, as to be educated by 
 him. Kinairdy had no more sons professors 
 than the three you mention, who were all 
 professors before he died. David and Jameg 
 were of the first marriage, and Charles of 
 the second. The two first were settled 
 before the Revolution — David as Professor 
 of Mathematics at Edinburgh, and, I sup- 
 pose, immediately succeeded his uncle, and 
 .James as a Professor of Philosophy at St 
 Andrews. I think I have a printed thesis of 
 .Tames, published at St Andrews before the 
 Revolution, which is a compeiid of Newton- 
 ian philosophy, with some strictures against 
 tlie scholastic philosophy. With regard to 
 the ten categories in particular, he says 
 there neither are nor can be more than two 
 categories, viz. Data and Qusesita.f I be- 
 lieve he was the first professor of philosophy 
 that taught tlie doctrines of Newton in a 
 Scotch university ; for the Cartesian was 
 
 of Medicine, in the University of Edinburgh ; and 
 author of "Conspectus Medicinae Theoretica;," of 
 " Philosopliical and Literary Essays," and of various 
 other works, distinguished by a talent which promises 
 still to be hereditary. 
 
 • Ihe murder here a'liidcd to was committed on 
 Alexander Gregory of Netlierdeel, eldest son and 
 heir ot the Rev. John Gregory, iniiiistfr of Drumoak ; 
 and the person in licted fnr the crime, was James 
 (Crichtoii) Viscount Frciidraught. The Books of 
 Adjournal (records ot the Scottish Criminal Court) 
 detail the circumstances of the case. In 1654-, Alex. 
 Snder Gregory, who ht'ld, in security, a part of 
 the estate of Frendraught, was decoyed by Francis 
 Crichton, the Viscniini't uncle, to accompany hira 
 to Ihe house of Bopnie, where that iioiileman then 
 lodged. Oil the way he was ass.iulted liy Crichtoii 
 and his servant ; and, after he had surrendered hs 
 arms, w:is wounded ' y them with swords ai d pistols, 
 andthen carried a prisoner to Bognie. Here he was 
 watched during the night, among others, by the Vis. 
 count, whose servants, next day, early in a rod morn, 
 ing, threw him across a horse, his wounds undressed 
 and bleeding, and broujiht him to a lone cottage, 
 where he was Kft till found by his friends, who con. 
 veyed him to Aberdeen, where, after langiii>hiiig for 
 a few days, he died Mr Francis and I i. serv.mt did 
 not comptar. The rel'^vaiicy of the libel aganst l.ord 
 Freiidraught was impugne<t, on the ground that the 
 cr mes libelled being only stntutory, and the pannel a 
 minor, they ouyht not to pass to an a-.i/.i- Bui, ih' luh 
 the ihel was f uiid re'evaiit, the proof ceems to have 
 been defective ; thejuiy,at leist, lound a verdict of ac. 
 quittal — 1 am indentid for ihi* iidormatiou to Duii~ 
 can Gregory and James Maidinent, Esquires. — H. 
 
 + This illustrates a statement in " The Analysis 
 of Aristotle s Logic," ch. ii. sec. i. — H.
 
 LETTERS TO DR JAMES GREGORV. 
 
 m 
 
 the orthodox system at that time, and con- 
 tinued to be so till 1715. I asked him once 
 how he came to give up his place at St 
 Andrew's on the change of government, 
 and afterwards to take the mathematical 
 chair at Edinburgh. " Faith, nephew," said 
 he, " I never minded politicks much ; but 
 my dearest companions in the college were 
 going out, and I did not like those that were 
 to keep their places ; and I thought it better 
 to go out in good company, than to stay be- 
 hind with ill." I believe Kinairdy's mathe- 
 matical and medical knowledge was the 
 effect of his own study and reading. He 
 was much employed as a physician, not 
 only by the poor, but by the nobility and 
 gentry; but he took no fees ; and, I conceive, 
 his younger brother and his sons had their 
 mathematical education chiefly from him. 
 He had a barometer, and had a correspon- 
 dence with some foreigners, particularly with 
 Mariotte, on barometrical observations. As 
 a barometer had never been heard of in his 
 country before, he was once in danger of 
 being brought to some trouble by the Pres- 
 bytery on account of it. In Queen Ann's 
 war, Kinairdy employed liiniself upon an 
 invention for improving the eft'ect of fire- 
 arms, of which he at last completed a model, 
 and sent it to his son David at Oxford, that 
 he miglit take the opinion of Sir Isaac New- 
 ton about it. I have heard my mother say 
 that he was so sanguine upon this project, 
 that he intended to make a campaign in 
 Flanders himself, and prepared for it. But 
 it is said that Sir I. Newton persuaded the 
 suppression of the invention as destructive 
 of the human species, and that it was never 
 brought to light. I knew a clockmaker in 
 Aberdeen who made all the parts by Kin- 
 airdy's direction ; but never saw them put 
 together, and could give no account of the 
 priiici|iles of it. Kinairdy carried his 
 family over to Holland, about the year 
 I7I0, as I believe, and, after some time, 
 returned to Aberdeen, and • died soon after. 
 His widow was alive when I went first to 
 Aberdeen in April 1722; but old and bed- 
 rid. I never saw a more ladylike woman ; 
 I was now and then called in to her room, 
 when she sat up in her bed, and enter- 
 tained with sweetmeats and grave advices. 
 Her daughters, that assisted her often, as 
 well as one who lived with her, treated her 
 as if she had been of a superior rank ; and, 
 indeed, her appearance an<l manner com- 
 manded respect. I don't believe that she 
 could ever descend so far from her dignity 
 and magnanimity as to scold. And the 
 reverence paid her by all her descendants 
 to the last period of her life, seems incon- 
 histent with that character. She and all 
 her ehildr'-n were zealous Presbyterians. 
 The first wife's children were rather Tories 
 and Kpiscooalians. I believe she had much 
 
 ado to keep up her authority with them 
 while they were in the family. David and 
 James, when prosecuting their studies at 
 Edinburgh, used to pass their vacations at 
 Kinairdy ; and very often Dr Pitcairn, or 
 some other fellow-student came along with 
 them ; and, as the master of the family was 
 very much from home, it was not easy for a 
 stepmother to keep them to her rules. One 
 of her stepdaughters married a Mr Cuthbert, 
 of the family of Castlehill, a writer in Aber- 
 deen, and was the mother of David Cuth- 
 bert, who saved millions to the nation in 
 the war before last, by controling the 
 accounts of the commissaries in Germany. 
 
 Another daughter of the first marriage, 
 married a Mr Innes of Tilliefour. A 
 grandson of hers, Alexander Innes, was a 
 professor of philosophy in Marischal College, 
 Aberdeen. He had a great turn to natural 
 history and to medicine ; but died young. 
 
 My mother, Margaret Gregory, was the 
 oldest daughter of the second marriage. 
 Besides Charles, there was a George of the 
 second marriage, a merchant in Campvere, 
 and the father of David Gregory at Dun- 
 kirk, and of John Gregory at Campvere. 
 Your uncle, David Gregory, served an 
 apprenticeship to this George Gregory, and 
 married his widow after his death. Charles 
 told me that his brother George fell to the 
 study of mathematics in Holland, and wrote 
 him an account of his discoveries. But 
 Charles bid him mitid his mercantile affairs ; 
 for these things had been discovered already 
 by authors he was unacquainted with. The 
 oidy daughter of the second marriage, besides 
 my mother, who left issue, was Anne, the 
 youngest daughter, grandmother to James 
 Bartlet, banker in Edinburgh. 
 
 The story of the watch, to which, I sup- 
 pose, you allude, I have heard very often. 
 By the descendants of the first wife it was 
 imputed to the second wife ; but the de- 
 scendants of the second wife imputed it to 
 the first wife. The first titne I was in 
 Dean Gregory's house at Oxford, he told 
 it very well to a large company of Oxonians. 
 He prefaced it by saying that his grand- 
 father had a termagant to his second wife ; 
 but turning to me and another Scotch gen- 
 tleman that was with me, he said, " I beg 
 your pardon, gentlemen, for I don't know 
 but one of you may be come of her." I 
 answered that I believed I had heard the 
 story he was about to tell, and heard it 
 imputed to the first wife, of whom he was 
 come ; but it was no matter which : I begged 
 he would proceed. To this ho agreed, and 
 proceeded to the story of the watch.* 
 
 Another story, somewhat similar, is told 
 of Kinairdy. On some occasion his wife, 
 I know not which wife, insisted very pcr- 
 
 * Which id now forgotten In thcfamily. — -H.
 
 70 
 
 CORRESPONDENCE OF DR REID. 
 
 emptorily that he should correct two of his j 
 sons, which, it seems, he was not accus- 
 tomed to do ; but the offence was such, that 
 nothing less would satisfy the wife. He 
 took them to a room where his saddle and 
 bridle hung, and shut the door. What 
 satisfaction he required for the fault I know 
 not; but, after the matter was compromised, 
 he took the bridle, and lashed the said saddle 
 very unmercifully, and ordered the boys to 
 cry, which they did most pitifully. The 
 mother hearing the noise, thought her boys 
 would be killed, and wanted to interpose, 
 but the door was bolted- She was forced 
 to stand behind the door, and felt every 
 stroke more than either the saddle or the 
 boys, resolving never again to trust her 
 husband with the rod of correction. 
 
 I have found the printed thesis of James 
 Gregory, above mentioned ; it is printed at 
 Edinburgh, 1690. It would seem that the 
 reform of St Andrew's University, after the 
 Revolution, was not overtaken at that time. 
 The students' names who were to defend the 
 thesis at Salvator College, in St Andrew's, on 
 such a day of June, are all mentioned, to the 
 number of twenty-one. Kinairdy was a 
 Scotch Episcopalian. He wrote memoirs 
 of his own times, which my father, who had 
 read them, told me were unfavourable to 
 the Covenant— the idol of the Presbyte- 
 rians at that time. These Memoirs were 
 in your father's possession, and I suppose 
 are in yours. You see, my dear sir, that 
 I have answered more than I was asked, 
 because I like to dwell upon the subject ; 
 but you must not think nor say that my 
 grandmother was a scold ; she might have 
 strong passions, but no scold ever had her 
 dignity and magnanimity. She had a 
 brother, whom I knew well, who was very 
 like to her — Provost John Gordon. He 
 was long at the head of the magistracy in 
 Aberdeen ; and had been a member of the 
 Scotch Parliament, and was one of the most 
 respected magistrates that ever was in that 
 city. — I ever am, dear Sir, yours, 
 
 Tho. Reid. 
 Aug. 24, 1787. 
 
 XI. 
 
 .N THE ORIGIN, PROGRESS, AND THEORV OF 
 LANGUAGE. 
 
 Dear Sir, — I have read your theory of 
 the moods of verbs* over and over, and 
 shall give you a few trifling remarks when 
 the MS. is returned, or sooner, if I see you 
 sooner. It is not yet sent to Dr Cleghorn, 
 but shall be this week. In the meantime, 
 
 • Siihsequetitly printed in "The Transactions of 
 the Koyal Society of Edinburgh."— H. 
 
 having the opportunity of my good friend 
 Mr John Duguid, I send you some reveries 
 on the invention and progress of language. 
 The art of communicating our sentiments 
 by articulate sounds,is certainly, of all human 
 arts, the most ingenious, and that which 
 has required most of thought, of abstraction, 
 and nice metaphysical discrimination. This 
 has led our friend L. M.* to think that it 
 must have been, at first, the work of philo- 
 sophers. I rather consider it as a huge and 
 complicated machine, which was very im- 
 perfect at first, but gradually received im- 
 provements from the j udgment and invention 
 of all who used it in the course of many 
 ages. 
 
 It is a machine which every man must 
 use, and which he finds of such utility and 
 importance, that, if he has any genius, he 
 has sufficient inducement to employ it in 
 making language more subservient to his 
 purpose. 
 
 In the natural talents of genius and in- 
 vention, there is no less difference among 
 savages than among philosophers. One 
 savage, in the use of natural signs, will shew 
 great superiority to others in conveying his 
 sentiments distinctly and intelligibly ; and 
 the same superiority he will shew in the use 
 of a rude language of articulate sounc?s — 
 sometimes by giving a more easy or more 
 agreeable sound to words that are in use ; 
 sometimes by distinguishing, by some in- 
 flection or inversion, words or phrases that 
 were before ambiguous ; sometimes by a 
 new metaphorical meaning ; and sometimes 
 by new words or new derivations, where 
 they were wanted. 
 
 So fond are ingenious men to invent such 
 improvements in language, and so prone the 
 multitude to adopt them, when they please 
 the public taste, that all languages are per- 
 petually changing, according to the beau- 
 tiful simile of Horace — Ut s'llvce foUis pronas 
 mutantur in annos, ^ c. In a rude language 
 it is easy to make improvements; and changes 
 that are found useful and important, though 
 invented by one man, will soon be adopted 
 by the multitude. 
 
 Thus the inventions of thousands of in- 
 genious men, in a succession of ages, all 
 employed upon this one machine, bring it 
 by insensible degrees to its perfection ; as 
 knowledge grows, language grows along 
 with it, till it arrive at that stately form 
 which we contemplate with admiration. 
 
 The steam engine was invented not much 
 more than a century ago ; but it has re- 
 ceived so many and so great improvements 
 in that short period, that, if the inventor 
 were to arise from the dead, and view it in 
 its improved state, he would hardly be able 
 to discern his own share of the invention, 
 
 » Lord Monboddo.— H.
 
 LETTERS TO DR JAMES GREGORY. 
 
 71 
 
 Language is like a tree, whicli. from a small 
 seed, grows imperceptibly, till the fowls of 
 the air lodge in its branches, and the beasts 
 of the earth rest under its shadow. The 
 seed of language is the natural signs of our 
 thoughts, which nature has taught all men 
 to use, and all men to understand. But its 
 growth is the efliect of the united energy of 
 all who do or ever did use it. One man 
 pushes out a branch, another a leaf, one 
 smootlis a rough part, another lops off an 
 excrescence. Grammarians have, without 
 doubt, contributed much to its regularity 
 and beauty ; and philosophers, by increasing 
 our knowledge, have added many a fair 
 branch to it ; but it would have been a tree 
 without the aid of either. 
 
 The rudest tribes of men soon find lan- 
 guage to express their confined wants and 
 desires ; and the natural love of analogy 
 will produce nnich analogy even in the lan- 
 guage of savages. We see that children of 
 two or three years old, having got a few 
 plurals, witliout bemg taught, form new 
 ones analogically, and often, in the pursuit 
 of analogy, break chrough the rules of 
 grammar. 
 
 A man born deaf, who has no opportunity 
 of conversing with other deaf men, has to 
 invent a language for himself, along with the 
 additional labour of teaching others to un- 
 derstand it. One who has had access to 
 know to what degree of perfection some 
 deaf men have carried their art of commu- 
 nicating their thoughts, will not think it 
 incredible that a nation flourishing in arts 
 and sciences should, in a course of ages, by 
 their united efforts, bring language to all 
 the perfection it has ever attained. 
 
 In speech, the true natural unit is a sen- 
 tence.* Xo man intends less when he 
 speaks ; what is less than a compleat sen- 
 tence is not speech, but a part or parts of 
 speech ; to divide a sentence into parts 
 requires greater abstraction than to divide 
 the unit into fractions of a unit. It is, 
 therefore, extremely probable that men ex- 
 pressed sentences by one complex sound or 
 word, before they thought of dividing thcin 
 into parts, signified by difl'erent words. One 
 word signified, give me In cad ; another, take 
 bread ; anotlier, eat brea<l ; another, bake 
 bread. As all these sentences have some- 
 thing common in their meaning, the natu- 
 ral love of analogy would lead to some- 
 thing common in the word by which they 
 were expressed; and in the progress of 
 language, that wliich was common in the 
 sound of all these sentences might be sepa- 
 rated from that which was projjcr to each ; 
 and, being thus ncparated, it becomes that 
 part of speech wliich we call a substantive 
 
 • 'Ihli is an important truth, the ignorance of 
 which is won in hut i>crv<T'«i nyRtcms of Griiinmar, 
 Logic, and rsjcliology. — 11. 
 
 noun, signifying bread, which substantive 
 will be fit to make a part of many other 
 sentences. 
 
 Thus the object, or accusative, may be, 
 as it were, cut out of the sentence, so as to 
 form a word by itself, though originally it 
 was only a part of a word. 
 
 Another set of sentences — such as, / live 
 Martha, Y'ou love Mail/, John loves Matilda 
 — might lead men to separate what is com- 
 mon in the word by which each of these 
 three sentences is expressed, from what is 
 proper to each, and by that means to have 
 a word for the verb love. 
 
 To shew how all the parts of speech may 
 be cut out of words that signify whole sen- 
 tences, by separating that part of the sound 
 \\hich is common to many sentences, from 
 that which is proper to each, would be more 
 tedious than difficult, and may easily be 
 conceived. By dividing the sound, the 
 mental abstraction is made easy, even to 
 rude men, who, without some aid of this 
 kind, would find it above their reach. Such 
 division facilitates greatly the use of lan- 
 guage, and, therefore, when once begun, 
 will go on. 
 
 That the parts of speech should be con- 
 ceived before speech was in use, and that 
 speech should at first be formed by putting 
 together parts of speech, which before had 
 got names, seems to me altogether incred- 
 ible ; no less incredible than if it should be 
 said that before men had the conception of 
 a body, they first formed the conception of 
 matter, then the conception of form, and, 
 putting these two together, they got the 
 conception of body, whicli is made up of 
 matter and form. 
 
 Perhaps, in the language of some savages, 
 all the parts of speech have not yet been 
 separated into ditt'erent words. Charlevoix 
 has given a very full account of some of the 
 Canadian languages. I quote him from 
 memory, having read his history of Canada, 
 I think, about forty years ago ; but, as it 
 first led me into this speculation, I remem- 
 ber it the better. 
 
 He says, 'of one of their languages, (I 
 think that of the Hurons,) that in each of 
 their villages there is a public orator cho.sen, 
 who makes it tlie whole study of his life to 
 speak the language with propriety and force; 
 that the people are very nice judges of the 
 defects and excellencies of their orators ; 
 so that there arc very few of them that can 
 perfectly please the public ear ; that their 
 verbs have as many moods and tenses as 
 the Greek verbs have, and, besides this, 
 that the accusative or object always makes 
 a part of the verb. Thus, one verb siyiti- 
 Jies to drink wine; another, to drink water ; 
 one, to kill a brother ; another, to kill an ene- 
 mij , so that the verb very often expresses 
 the whole sentence.
 
 CORRESPONDENCE OF DR REID. 
 
 I believe, in all languages of nations 
 which we account civilized, the several parts 
 of speech have been separated from one an- 
 other, and are often expressed by words 
 proper to them. But in all of them, and in 
 some more than in others, several parts of 
 speech are often combined in one word, not 
 from necessity, but for the sake of elegance 
 and beauty. 
 
 Thus, in the Latin and Greek verbs, be- 
 sides the radical signification of the verb, 
 its voice, mood, tense, person, and number 
 are all expressed in one word. In nouns, 
 both substantive and adjective, we have the 
 noun, together with its case, number, and 
 gender, in one word. Nor is this owing to 
 a want of words in those languages to ex- 
 press separately those accidents of verbs and 
 nouns. It seems rather to be a matter of 
 choice, to give greater beauty and strength 
 to the language. By this expedient, much 
 may be said in few words— and these, lofty 
 and sonorous words, with a beautiful variety 
 and harmony of termination, and great 
 power of inversion ; which are qualities of 
 great importance in poetry and eloquence. 
 In language, as in many other things, 
 necessity, convenience, and long practice, 
 have, without the rules of art, produced 
 artifices, which the artist or the philosopher 
 has reason to admire, which, sitting in his 
 chair, he would never have been able to 
 invent, and which, now that they are in- 
 vented, he finds it very difficult to reduce 
 to principles of art. 
 
 I believe the principles of the art of lan- 
 guage are to be found in a just analysis of 
 the various species of sentences. Aristotle 
 and the logicians have analysed one species — 
 to wit, the propoiitioti. To enumerate and 
 analyse the other species, must, I think, be 
 the foundation of a just theory of language. 
 •^I am, dear Sir, yours affectionately, 
 
 Tiio. Reid. 
 yluff. 26, 1787. 
 
 XII. 
 
 [1788.] 
 Dear Sir, — I received yours of Feb- 19, 
 and last evening received, by the fly, the 
 very acceptable present of the new edition 
 of your father's works, for which I heartily 
 thank you. I have read the Life, which I 
 think well wrote. I am much obliged to 
 the author* of it for the notice he has taken 
 of me ; but I wish he had spared some 
 epithets, which I could not read to myself 
 without a blush ; I have exceptions to 
 some things in the narrative, but they 
 relate to unimportant circumstances. The 
 quotation from '■ Whiston's Memoirs" de- 
 lighted me, and does honour to Scotland. -f 
 
 • Lord Woodhouselee.— H. 
 
 t It i» of the following purport : — Speaking of Dr 
 
 Perhaps it might have been added, that 
 James, the brother of David, was at that 
 time teaching the same doctrine, as a Pro- 
 fessor of Philosophy, in another Scotch 
 university. I have by me a thesis he 
 published in 1G90, which is a compend of 
 the conclusions of Newton's " Principia," 
 I have always heard, by tradition, tliat D. 
 Gregory, the astronomer, was chosen to be 
 preceptor to the Duke of Gloucester, Queen 
 Ann's son ; but whether his entering upon 
 that office was prevented by his death, or 
 by the death of the young prince, I know 
 not. I have also heard that the Profession 
 of Modern History in Oxford was erected in 
 favour of his son, David, when he came 
 home from his travels-" 
 
 I am happy in the account you give me 
 of our friend, William. I hope he will 
 continue the race of the Gregories, if you 
 do not — which, however, I do not yet de- 
 spair of. Our University has sent a petition 
 to the House of Commons, in favour of th? 
 African slaves. I hope yours will not be 
 the last in this humane design ; and that 
 the Clergy of Scotland will likewise join in 
 it. I comfort my grey hairs with the thoughts 
 that the world is growing better, having long 
 resolved to resist the common sentiment of 
 old age, that it is always growing worse. 
 I am grown so deaf that I can only converse 
 with one person, and that when he speaks 
 into my left ear ; but I hope to resist that 
 depression of spirits which commonly at- 
 tends that disorder. I can see people con- 
 versing together without any uneasiness ; 
 the only difficulty is, when a laugh is raised, 
 whether to langh at one does not know what, 
 
 David Gffgory, when Professor of Mathematics at 
 Edinburgh, Whiston says — " He had already caused 
 several of his scholars to keep acts, as we call them, 
 upon several branches of he Newtonian philosophy, 
 while we at Cambridge, poor wretches ! were igiiomi. 
 niously studying the fictitious hypotheses of the Carte- 
 sian." — fVhi'.tton's Memoirs, p. ."j^ — There is in ihis, 
 however, no just ground of panegyric on Scotland. 
 In the intrusive system of tlie English universities, 
 where the tutor has illegally superseded the prolessor, 
 all change from one setof docirines to a better, must 
 be the tardy and painful work of time and necessity. 
 The evolutions of a university are iirompt and easy 
 where each department ol its cyclopadia is sepdratcly 
 taught by an able professor; when as a university 
 which abamlons instruction, in all branches, to any 
 inriividual ol a host of tutors — the majority o( whom 
 assume thi> ottice ol instructor for tiieirown conve. 
 nieiice, thouf>h without the ability adequate to dis. 
 charge its duties — such a university niu-t be content, 
 not only always to teach little, and that little ill, but 
 to continue often tor a long time to teach what 
 is cisewliere otisolete or exploded. Accordingly, in 
 New!on's own uinversity, ilie Cartesian theories con- 
 tinued to be tnugbt as the orthodox doctrine, after the 
 Newtonian physics had, in other uiuve'siiies, super- 
 seil<d the Cartesian. And why ? .simply becau-e, in 
 Camliri'ipe, instruction was carried on by tutors ; and 
 the majority of the Cambridge tutors, educa ed in the 
 old system, woe unable or unwilling to qualify them, 
 selves to become instructors in the new. — H. 
 
 • David Gregory, the son, was.certainlyj?rj< Pro. 
 fetsor in the chair ot Modern History and Languages, 
 founded by ■George I. — H,
 
 LETTERS TO DR JAMES GREGORY. 
 
 73 
 
 or to be grave when other people laugh. I 
 am very glad to hear that Dug. Stewart 
 lectures in physieks so acceptably, but wish 
 his health be not attected by his being over- 
 wrought I am, dear Sir, very afl'ection- 
 
 ately yours, 
 
 Tho. Reid. 
 
 XIII. 
 
 ON LSURY. 
 
 I am much 
 
 pleased with the tract you sent nie on 
 usury." I think the reasoning unanswer- 
 able, and have long been of the author's 
 opinion, though I suspect that the general 
 principle, tliat bargains ought to be left to 
 the judgment of the parties, may admit oi 
 some exceptions, when the buyers are the 
 many, the poor, and the simple— the sellers 
 few, rich, and cunning ; the former may 
 need the aid of the magistrate to prevent 
 their being oppressed by tlie latter. It 
 seems to be upon this principle that por- 
 tage, freight, the hire of chairs.und coaches, 
 and the price of bread, are regulated in most 
 great towns. But with regard to the loan 
 pf money in a commercial state, the excep- 
 tion can have no place — the borrowers and 
 lenders are upon an equal footing, and each 
 may be left to take care of his own interest. 
 Nor do I see any good reason for the inter- 
 position of law in bargains about the loan 
 of money more than in bargains of any 
 other kind. I am least pleased with the 
 10th letter, wherein he accounts for the 
 infamy of usury. In one of the papers you 
 mention, (which I give you liberty to ufe 
 as'you please,) I have attempted an accoui t 
 of that phenomenon, which satisfies me more 
 
 than his account docs I am, dear Sir, 
 
 Yours most affectionately, 
 
 Tho. Reid. 
 Glasf/ow, 5th Sep'. 1788. 
 
 XIV. 
 
 CAUSE — PHYSICAL CAUSE — LAWS OF NATURE 
 AGENT — POWER AND ACTIVITY. 
 
 My Dear Sir,— On Monday evening I 
 received your book,f with the letter in- 
 closed. The book I shall peruse at leisure 
 with the eye of a critick ; but, as it is pro]ier 
 to acquaint you soon of my having received 
 it safe, I shall now answer your letter, 
 though perhaps in too much haste. Your 
 
 • " Ix-ttcis On Usury," by Mr Jeremy Renlham, 
 afldrosnl in (ieotgo \Vil*(iii, K>q , (I)r firc'(!(iry'B 
 Iricnrl.) ai'd pubiishi-d Ijy .Mr VNilt-uiiin 1187 — H 
 
 + The " Philo«0|.hical and I itoiary hhSiiyR,'" or 
 rather their Introduction, which wui in Kfat part 
 printed (cveral jearis bclorc publication.— H. 
 
 intention of inscribing the book, if published, 
 to me, I account a very great honour done 
 me ; and, if you do not alter your mind, 
 would not be so self-denying as to decline 
 it ; but, as a real friend, I think you ought 
 to inscribe it to some man in power that 
 may be of use to you, though I hate dedi- 
 cations stuffed with flattery to great men. 
 Yet I know no reason why a man of your 
 time of life may not court the notice of a 
 great man by a dedication, as well as by a 
 visit. When I inscribed a book to you, 
 my situation was very dift'erent. I was past 
 all hopes and fears with regard to this 
 world ; and, indeed, had Lord Kaimes been 
 alive, intended to have addressed it to him. 
 When he was dead, there was not a man 
 of his eminence that I had so much ac- 
 quaintance with as to j iistify such an address. 
 I therefore seriously wi h you to spend a 
 second thought upon this subject ; and not 
 to suffer your friendship, of wiiich I need 
 no new proof, to lead you to do an impru- 
 dent thing, and what the world would thigk 
 such, or even perhaps construe as a con- 
 tempt put upon your ^n-i/ friends.* 
 
 As to the two ponts wherein you and I 
 differ, after what you have said of them in 
 this letter, I am really uncertain wlietlier 
 we differ about things or only about words. 
 You deny that of every change there must 
 he an efficient cause, in my sense — that is, 
 an intelligent agent, who by his power and 
 will effected the change. But I think you 
 urant that, when the change. is not effected 
 by such an agent, 'it nmst have a piiysical 
 cause — tiiat is, it must be the necessary 
 consequence of thenatureand previous state 
 of things unintelligent and inactive. 
 
 I admit that, for anything 1 know to the 
 contrary, there may be such a nature and 
 state of things which have no proper ac- 
 tivity, as that certain events or changes 
 must necessarily follow. I admit that, in 
 such a case, that which is antecedent may 
 be called the physical cause, and «hat is 
 necessarily consequent, may be called the 
 effect o*' that cause. 
 
 I likewise admit, laws of nature may be 
 called (as they commonly are called) phy- 
 sical causes — in a sense indeed somewhat 
 different from the former— because laws of 
 nature effect nothing, but as far as they are 
 put to execution, either by some agent, or 
 by some physical cause ; they being, how- 
 ever, our HI- plus nil I a in natiiral phi osoi)hy, 
 which professes to shi'W us the causes of 
 natural things, and being, both in ancient 
 and modern times, called caiisfs, tlicy have 
 by prescrii)tion acquired a right to that 
 name. 
 
 I tliink also, and I believe you agree with 
 
 • It. is needless to say that l)r Gregory did not 
 comply wilh this prudei.t advice. '1 he " E«.''ayi" 
 are iiedicated to Heid.— H.
 
 74 
 
 CORRESPONDENCE OF DR REID. 
 
 me, that every physical cause must be the 
 work of some agent or efficient cause. Thus, 
 that a body put in motion continues to move 
 till it be stopped, is an effect which, for what 
 I know, may be owing to an inherent pro- 
 perty in matter ; if this be so, this pro- 
 perty of matter is the physical cause of the 
 continuance of the motion ; but the ultimate 
 efficient cause is the Being who gave this 
 property to matter. 
 
 If we suppose this continuance of motion 
 to be an arbitrary appointment of the 
 Deity, and call that appointment a law of 
 nature and a physical cause ; such a law of 
 nature requires a Being who has not only 
 enacted the law, but provided the means of 
 its being executed, either by some physical 
 cause, or by some agent acting by his order. 
 If we agree in these things, I see not 
 wherein we differ, but in words. 
 
 I agree with you that to confound the 
 notion of agent or efficient cause with that 
 of physical cause, has been a common error 
 of philosophers, from the days of Plato to 
 our own. I could wish that the same gene- 
 ral name of cautx had not been given to 
 both, as if they were two species belonging 
 to the same genus. They differ toto gencre.. 
 For a physical cause is not an agent. It 
 does not act, but is acted upon, and is as 
 passive as its effect. You accordingly give 
 them different generical names, calling the 
 one the agent, and not the cause — the other 
 the cause, but not the agent. 
 
 I approve of your view in this ; but think 
 it too bold an innovation in language. In 
 all writing, preaching, and speaking, men 
 have been so nmch accustomed to call the 
 Deity the first cause of all things, that to 
 maintain that he is no cause at all, would 
 be too shocking. To say that the world 
 exists without a cause, would be accounted 
 Atheism, in spite of all explications that 
 could be given of it. Agency, efficiency, 
 operation, are so conjoyned in our concep- 
 tions with a cause, that an age would not be 
 sufficient to disjoyn them. 
 
 The words agent and action are not less 
 ambiguous than cause and causation ; they 
 are applied, by the most accurate thinkers 
 and speakers, to what you call physical 
 causes. So we say, one body acts upon 
 another, by a stroke, by pressure, by attrac- 
 tion or repulsion ; and in vain would one 
 attempt to abolish this language. "We must 
 bear with the imperfections of language in 
 some degree ; we are not able to make it 
 so philosophical as we wish. 
 
 To remedy the ambiguity of cause and 
 agent as far as possible, without too bold 
 an innovation, I say that each of these 
 words has two meanings — a lax and popular 
 meaning, and a philosophical. In the po- 
 pular meaning, both are applied to what you 
 call a physical cause. In the strict or philo- 
 
 sophical meaning, both are applied onely to 
 what you call an agent — I, an efficient 
 cause. I choose to distinguish the philoso- 
 phical meaning of cause, by calling it an 
 efficient cause ; and to distinguish the 
 philosophical meaning of agent, by calling 
 it an agent in the strict and proper sense. 
 
 You distinguish the philosophical mean- 
 ing of these two ambiguous words from the 
 popular, by appropriating one to the philo- 
 sophical meaning, and the other to the 
 popular. Is not this the difference between 
 you and me ? 
 
 It is remarkable that the philosophical 
 meaning of those two words, and of the 
 others that depend upon them, must have 
 lieen the first, and the popular meaning a 
 corruption of the philosophical, introduced 
 by time, but so deeply rooted in the struc- 
 ture of all languages, that it is impossible 
 to eradicate it ; for nothing external to us 
 could introduce into the human mind the 
 general notion of priority and constant con- 
 junction, but nothing farther. 
 
 Power and activity are first conceived 
 from being conscious of them in ourselves. 
 Conceiving of other beings from what we 
 know of ourselves, we first ascribe to them 
 such powers as we are conscious of in our- 
 selves. Experience, at least, informs us 
 that the things about us have not the same 
 powers that we have ; but language was 
 formed on a contrary slipposition before 
 this discovery was made, and we must give 
 a new, and perhaps a very indistinct, mean- 
 ing to words which before had a clear and 
 distinct one. 
 
 As to the other difference you mention 
 between you and me, I have quite forgot it. 
 But I think one can hardly be too cautious 
 of denying the bona files of an antagonist 
 in a philosophical dispute. It is so bitter a 
 pill, that it cannot be swallowed without 
 being very well gilded and aromatized. I 
 caimot but agree with you that assent or 
 belief is not a voluntary act. Neither is 
 seeing when the eyes are open. One may 
 voluntarily shut his bodily eyes, and perhaps 
 the eye of his understanding. I confess 
 this is mala fides. But as light may be so 
 offensive that the bodily eye is shut involun- 
 tarily, may not something similar happen to 
 the eye of the understanding, when brought 
 to a light too offensive to some favourite 
 prejudice or passion, to be endured ?* 
 
 As soon as I have done with your book, I 
 shall execute your commission to Mr Ar- 
 thur. — I am, dear Sir, yours very sincerely, 
 
 Tho. Reid. 
 Thursday, July 30, 1789- 
 
 * This passage (" But 1 think"—" be endured ?"') 
 is quoted in the Introduction to Or Gregory's Essays, 
 p. 3li;.— H.
 
 LETTERS TO DR JAMES GREGORY. 
 
 75 
 
 XV. 
 
 ARISTOTELIC SFECIES OF CAUSES — ORIGIN OF 
 
 NOTIONS OF CAUSE AND POWER WHAT ES- 
 
 SMNTIAL TO THE NATURE OF CAUSE — DIS- 
 TINCTION OF PHYSICAL AND METAPHYSICAL 
 CAUSES. 
 
 Remarks on the Inlroduction* 
 
 1. I humbly think you are too severe 
 against Aristotle and Plato, especially the 
 former. i" Two hundred years ago, it was 
 proper to pull him down from the high seat 
 he held ; but now he is sufficiently humbled, 
 and I would not have him tramjiled upon. 
 I confess that his distinction of causes into 
 four kinds is not a division of Hffenui into its 
 species, but of an ambiguous word into its 
 different meanings, and that this is the case 
 with many of his divisions. But, in>the in- 
 fancy of philosophy, this ought to be corrected 
 without severity. It was more inexcusable 
 in many philosophers and divines of the 
 seholastick ages to handle every subject in 
 one method, namely, by shewing its four 
 causes — Efficient, Material, Formal, and 
 Final. A very learned divine, whose compend 
 was the text-book in the school where I was 
 taught, treating of the creation, when he 
 comes to the material cause, pronounces it 
 to be nihil. If Aristotle had treated of his 
 materia prima in this method, he must have 
 made the mateiial cause to be the thing it- 
 self, and all the three other causes to be 
 nihil ; for it had no form, no efficient, con- 
 sequently no end. But the absurdity of 
 making everything to have four causes, can- 
 not, I believe, be imputed to Aristotle. 
 
 2. You challenge him with a violation of 
 propriety in the Greek language. J I am dis- 
 posed to take it upon the authority of Aris- 
 totle, as a man wlio understood Greek better 
 than any modern, that the word kiTnti was 
 sometimes used to signify the form, some- 
 times the matter of a thing. If these were 
 not j)0])ular meanings of the word, might 
 they not be philosophical, and perhaps to bo 
 found only in the writings of philosophers, 
 which are now lost ? But I cannot think 
 that Aristotle would have given these mean- 
 ings without authority ; and I think it bold 
 in any modern to impute this to him, 
 
 3. You are likewise severe upon the to tj ». || 
 May it not be .said that it is very like the sup. 
 po<r'l principle of chanffe, which, in page xvii., 
 you make the general meaning of the word 
 
 CUltSf ? 
 
 4. You seem to think (end of page xxi.) 
 tliat there are different kinds of causes, each 
 
 • " Introduction to the Eisay," Xc. printed in 
 part. — H 
 
 i Viile " K««ivfi," Iiitroniiclinn, ji xvi. nq. — H. 
 { /Wdrm, p. xvii — H. {] l/iiJem,p xvii.— II. 
 
 having something specifick in its relation to 
 the ef?'ect. 
 
 I know not what the kinds are which you 
 have in your eye, and therefore speak in 
 the dark upon this point. I mean onely to 
 put you upon your guard that they be 
 really specirs of the same neniis, that you 
 may not fall under the censure you have 
 passed upon Aristotle. 
 
 You will forgive my offering this caution, 
 because I apprehend that there is one ori- 
 ginal notion of cause grounded in human 
 nature, and that this is the notion on which 
 the maxim is grounded — that every change 
 or event must have a cause. This maxim is 
 so universally lield, and forces itself upon 
 the judgment so strongly, that I think it 
 must be a first principle, or what you call a 
 law of human thought. And I think the 
 only distinct and true meaning of this maxim 
 is, that there must be something that had 
 power to produce the event, and did pro- 
 duce it. We are early conscious of some 
 power in ourselves to produce some events ; 
 and our nature leads us to think that every 
 event is produced by a power similar to that 
 which we find in ourselves— that is, by will 
 and exertion : when a weight falls and hurts 
 a child, he is angry with it — he attributes 
 power and will to everything that seems to 
 act. Language is formed upon these early 
 sentiments, and attributes action and power 
 to things that are afterwards discovered to 
 have neither vvill nor power. By this 
 means, the notion of action and causation is 
 gradually changed ; what was essential to it 
 at first is left out, while the name remains : 
 and the term cause is applied to things whicli 
 we believe to be inanimate and passive. 
 
 I conceive that, from the original notion 
 or sentiment above described, all the dif- 
 ferent notions of cause have been derived, 
 by some kind of analogy, or perhaps abuse ; 
 and I know not but the « ll » may compre- 
 hend them a!l, as well as any other general 
 name, as they are so heterogeneous. 
 
 A law plea is the cause of a litigation. 
 The motive that induces a great body of men 
 to act in concert, is the cause of a revolu- 
 tion in politicks. A law of nature is the 
 cause of a phenomenon in physicks, or, 
 perhaps, the cmise is another i)henomeiion 
 which always goes before it. 'l"ho cause of 
 the universe has been by some thought to 
 be necessity, by others chamc, by others a 
 powerful intelligent being. 
 
 I think it is a good division in Aristotle, 
 that the s;ime word may be applied to dif- 
 ferent things in three ways — univocally, 
 analogically, and equivocally. Univocally, 
 when the things are species of the same 
 (/niiis ; analogically, when the things ure 
 related by some similituile or analogy ; o(|iii- 
 vocally, when (hey have no relation l)iit a 
 common name. When a word is nnalogi-
 
 76 
 
 CORRESPONDENCE OF DR REID. 
 
 cally applied to different things, as, I be- 
 lieve, the word cause is, there must be an 
 original meaning from which the things 
 related to it have borrowed the name ; and 
 it happens not unfrequently that the origi- 
 nal notion loses the name by disuse, while 
 the relatives monopolize it ; as in the Eng- 
 lish words, deliberate, suspense, project, 
 and many others. 
 
 The vulgar, in their notion even of the 
 physical cause of a phajnomenon, include 
 some conception of efficiency or productive 
 influence. So all the ancient philosophers 
 did. 1/aqit" nnn sic causa hiteUhji dehet, 
 ut o'li'd cuqne antecedat id ei causa sit, sed 
 qiod ejfi,:'ienter nntecedi: — Cicero. 
 
 Modern philosophers know that we have 
 no ground to ascribe efficiency to natural 
 causes, or even necessary connection with 
 the effect. But we still call them causes, 
 including nothing under the name but pri- 
 ority and constant conjunction. Thus the 
 giving tiie name of causation to the relation 
 of connected events in physicks, is, in mo- 
 dern philosophers, a kind of abuse of the 
 name, because we know that the thing 
 most essential to causation in its proper 
 meaning — to wit, efficiency — is wanting. 
 Yet this does not hinder our notion of a 
 physical cause from being distinct and de- 
 terminati', though, I think, it cannot be 
 said to be of the same genus with an effi- 
 cient cause or agent. Even the great Bacon 
 seems to have thought that there is a la'ens 
 processus, as he calls it, hi/ which natural 
 causes really produce their effects ; and 
 that, in the progress of philosophy, this 
 might be discovered. But Newton, more 
 enlightened on this point, has taught us to 
 acquiesce in i law of milure, according to 
 wfii h the eff"ect is produced, as the utmost 
 that natural philosophy can reach, leaving 
 what can be known of the agent or efficient 
 cause to metaphysicks or natural theology. 
 This I look upon as one of the great dis- 
 coveries of Newton ; for I know of none 
 that went before him in it. It has new- 
 modelled our notion of physical causes, but, 
 at the same time, carried it farther from 
 what I take to be the original notion of 
 cause or agent. 
 
 If you have found, as you seem to say, 
 (page xxii.,) that the different relations of 
 things, which we call cause and effect, differ 
 only as species of the same genus, and have 
 found the general notion which comprehends 
 them all under it— this, indeed, is more 
 than I am able to do. Supposing it to be 
 done, I should think that the genus, being 
 an abstract notion, would be capable of a 
 just definition. Yet I do not find fault 
 with your declining to set out by giving 
 the definition ; for I conceive you m:iy, 
 with great propriety, pave the way to it by 
 B preliminary induction. 
 
 XVI. 
 
 ON CA08K — OBJECTS OF GEOMETRV — PoWKR 
 AGENCY, &C. 
 
 [N^o dale.] 
 Mv Dear Sir, — I must thank you, in 
 the first place, for your attention to my in- 
 terest in writing to Dr Rose what you in- 
 formed me of in your answer to my last. 
 
 I received your three volumes* on Wed- 
 nesday evening, with the letter and plan of 
 the Essay. ... ... 
 
 Volume First. 
 
 In the induction made to prove that men 
 have a notion of the relation of cause and 
 effect, this case ought to be particularly in the 
 view of the author, (as I take it to be the 
 case that really exists) — to wit, that cause 
 and effect, from the imperfection of langu- 
 age, signifie many different relations, and 
 yet, by those wlio wx-ite and think dis- 
 tinctly, will be used without ambiguity ; 
 the things of which they are predicated ex- 
 plaining sufficiently what relation is meant. 
 This is the case of many words that have 
 various meanings really different, though, 
 perhaps, somewhat similar or analogous. 1 1 
 is remarkably the case of prepositions. Yet 
 such words as prepositions are used with- 
 oat ambiguity by those who think distinctly. 
 How many relations are expressed by the 
 preposition 0/ ? — and yet, when it is put be- 
 tween two words, we are never at a loss 
 for its meaning. In Aristotle's days, a cause 
 meant four things — to wit, the Efficient, 
 the Form, the Matter, and the End. Yet, 
 when it was used by a good writer, it was 
 easy to see in which of these senses it was 
 meant. With us the woi-d cause has lost 
 some of these' four meanings, and has got 
 others to supply their places, and, perhaps, 
 has not, in one language, all the meanings 
 which it has in another. Perhaps, therefore, 
 it may be said, that all men have many no- 
 tions of cause and effect, and some men 
 more than others ; the same observation 
 may, I think, be applied to the words Power, 
 Agent, and Activity. 
 
 To give you a hint of my notion of the 
 word cause, I think it has one strict and 
 philosophical meaning which is a single re- 
 lation, and it has a lax and jiopular meaning 
 which includes many relations. The popu- 
 lar meaning I think I can express by a 
 definition. Causa est id, quo podio pnn'Uur 
 
 • 'I he MS. of the Essay itself The E.«say was 
 pr hablv considerably modified before publication ; 
 and 1 nave been unable to attempt the tasl< of discover, 
 ing how far, and to -what pages of the published book, 
 the following remarks api'ly. — H.
 
 LETTERS TO DR JAMES GREGORY. 
 
 Effectus, quo sublato toUitur. This, you 
 will easily see, includes many relations, and, 
 I believe, includes all that inanylanguagsare 
 expressed by cau-e, thoughin some languages 
 some of the relations included under the 
 definition may not be called causes, on ac- 
 count, perha])s, of their having some other 
 word appropriated to signify such relations. 
 
 In the strict philosophical sense, I take a 
 cause to be that which has the relation to 
 the effect wliich I have to my voluntary and 
 deliberate actions ; for I take this notion of 
 a cause to be derived from the power I feel 
 in myself to produce certain effects. In 
 this sense, we say that the Deity is the 
 cause of the universe. 
 
 I think there is some ambiguity in your 
 use of the words The notiun of a cause. 
 Through a considerable part of Vol. I. it 
 means barely a conception of the meaning 
 of the word cause ; then suddenly it means 
 some opinion or judgment about the word 
 cause, or the thing meant by that word. 
 The last must be the meaning when you 
 speak of the notion of a cause being true or 
 false, being condemned or justified. The 
 bare conception of a cause, without any 
 opinion about it, can neither be true nor 
 false. It is true that notion often signifies 
 opinion ; but when, in a train of discourse, 
 it has been put for simple conception, and 
 then immediately for opinion, the reader 
 is apt to overlook the change of signification, 
 or to think that the author means to impute 
 truth or falsehood to a bare conception, 
 without opinion. 
 
 The same thing I observe when you 
 speak of the notion of power, vol. II. p. 19. 
 
 Page 40, &c. — What is said about the 
 non-existence of the objects of geometry, I 
 think, is rather too strongly expressed. I 
 grant that they are things conceived without 
 regard to their existence ; but they are pos- 
 sible modifications of things whicli wedayly 
 perceive by our senses. We perceive length, 
 breadth, and thickness : these attributes do 
 really exist. The objects of geometry are 
 modifications of one or more of these, accu- 
 rately conceived and defined. 
 
 Nor do I think it can be said, without great 
 exceptions, that the notions of the objects 
 of geometry are not common among man- 
 kind. The notions of a straight and a curve 
 line, of an angle, of a plain surface, and 
 others, are common; though, perhajis, in the 
 minds of the vulgar, not so accurately de- 
 fined xs in those of geometers. The more 
 complex geometrical conceptions of cycloids 
 and other curves, are only artificial com- 
 positions of more simple notions which are 
 common to the vulgar. ]I<,'nce, a man of 
 ordinary ca[)acity finds no difficulty in uiider- 
 8 anding the definitions of Euclid. All the 
 difiiculty lies in forming the habit by which 
 
 the name, and an accurate conception of its 
 meaning, are so associated, that the one 
 readily suggests the other. To form this 
 habit requires time, and in some persons 
 much more than in others. 
 
 Page 68. — You may use freedom with 
 Aristotle, because he won't feel it. But I 
 would not have you laugh at the restorer of 
 ancient metaphysicks* in publick while he 
 is alive. Why hurt a man who is not 
 hurting you ? 
 
 Page 70. — I thought the animal implume 
 bipes was Plato's definition, and I think I 
 quoted it as his ; but you may examine. I 
 think it is Diog. Laertius that says so ; but 
 I am not sure, nor have I the book here.-)* 
 
 What you say of definitions in natural 
 history, chemistry, and medicine, may per- 
 liaps be taken by some persons as a disap- 
 probation of definitions in those sciences. 
 Would it not be proper to guard against 
 this misconstruction ? I thiidi them very 
 useful to the present age, and that they 
 may be still more useful to future ages, 
 though you observe, very justly, that we can- 
 not reason from them as we do from mathe- 
 matical definitions. The most common 
 words may flow with the flux of time, and 
 have their meaning contracted, enlarged, or 
 altered, Definitioi seems to be the only 
 mean of fixing them to one meaning, or, at 
 least, of shewing what was the meaning when 
 that definition had authority. 
 
 Volume Second. 
 
 After what I have already said, you will 
 not be surprized to find me one of those 
 who think that the notions of Power and of 
 Agency or Activity, have a share in the rela- 
 tion of Cause and Ett'ect. I take all the 
 three words to have a lax and popular 
 meaning, in which they are nearly related ; 
 and a strict and philosophical meaning, in 
 which also they have the same affinity. 
 
 In the strict sense, I agree witli you 
 that power and agency are attributes of 
 mind onely ; and I think that mind onoly can 
 be a cause in the strict sense. This i)ow('r, 
 indeed, may be where it is not exerted, and 
 so may be without agency or causation ; but 
 there can be no agency or causation with- 
 out power to act, and to produce the effect. 
 
 As far as I can judge, to everything we 
 call a cause we ascribe power to produce 
 the effect. In intelligent causes, the power 
 may be without be ng exerted ; so I have 
 power to run, when I sit still or walk. But 
 in inanimate causes, we conceive no power 
 but what is exerted ; and, therefore, mea- 
 sure the power of the cause by the effect 
 
 • Lord Monhoildo.— H. 
 
 t See l.acrliui, I>. vl. Seg. 10. The dfflnillon If 
 riBtoV — H.
 
 78 
 
 CORRESPONDENCE OF DR REID. 
 
 wliich it actually produces. The power of 
 an acid to dissolve iron is measured by 
 what it actually dissolves. 
 
 We get the notion of active power, as 
 well as of cause and effect, as I think, from 
 what we feel in ourselves. We feel in our- 
 selves a power kto move our limbs, and to 
 produce certain effects when we choose. 
 Hence, we get the notion of power, agency, 
 and causation, in the strict and philosophical 
 sense ; and this I take to be our first notion 
 of these three things. 
 
 If this be so, it is a curious problem in 
 human nature, how, in the progress of 
 life, we come by the lax notion of power, 
 agency, cause, and effect, and to ascribe 
 them to things that have no will nor intel- 
 ligence. I am apt to think, with the Abb^ 
 Raynal, " that savages," (I add children 
 as in the same predicament,) " wherever 
 they see motion which they cannot account 
 for, there they suppose a soul." Hence 
 they ascribe active power and causation to 
 sun, moon, and stars, rivers, fountains, sea, 
 air, and earth ; these are 'conceived to be 
 causes in the strict sense. In this period 
 of society, language is formed, its funda- 
 mental rules and forms established. Ac- 
 tive verbs are applied onely to things that 
 are believed to have power and activity in 
 the proper sense. Every part of nature 
 which moves, without our seeing any exter- 
 nal cause of its motion, is conceived to be a 
 cause in the strict sense, and, therefore, is 
 called so. At length, the more acute and 
 speculative few discover that some of those 
 things which the vulgar believe to be ani- 
 mated like themselves, are inanimate, and 
 have neither will nor understanding. These 
 discoveries grow and spread slowly in a 
 course of ages. In this slow progress, what 
 use must the wise men make of their dis- 
 coveries ? Will they affirm that the sun 
 does not shine nor give heat, that the 
 sea never rages, nor do the winds blow, nor 
 the earth bring forth grass and corn ? If 
 any bold spirit should maintain such para- 
 doxes, he would probably repent his teme- 
 rity. The wiser part will speak the com- 
 mon language, and suit it to their new no- 
 tions as well as they can ; just as philoso- 
 phers say with the vulgar, that the sun 
 rises and sets, and the moon changes. The 
 philosopher must put a meaning upon vul- 
 gar language that suits his peculiar tenets 
 as well as he can. And, even if all men 
 should become philosophers, their language 
 would still retain strong marks of the opi- 
 nions that prevailed when it was first made. 
 If we allow that active verbs were made to 
 express action, it seems to be a necessary 
 consequence, that all the languages we 
 know were made by men who believed 
 almost every part of nature to be active, 
 and to have inherent power. 
 
 Volume Third. 
 
 The philological discussion is new to me ; 
 and it would require more time in my slow 
 way to make up my mind about it, than 
 you allow me. But the general principle — 
 that every distinction which is found in the 
 structure of a common language, is a real 
 distinction, and is perceivable by the com- 
 mon sense of mankind — this I hold for cer- 
 tain, and have made frequent use of it. I 
 wish it were more used than it has been ; 
 for I believe the whole system of metaphy- 
 sicks, or the far greater part, may be brought 
 out of it ; and, next to accurate reflexion 
 upon the operations of our own minds, I 
 know nothing that can give so much light 
 to the human faculties as a due considera- 
 tion of the structure of language. 
 
 From this principle, you prove to my 
 satisfaction that there is a real distinction 
 between the relation which a living agent 
 has to his action, and the relation between 
 an inanimate and the effect of which it is 
 the cause, mean, or instrument. 
 
 But I know no language in which the 
 word cause is confined to inanimate things, 
 though, perhaps, it may be more frequently 
 applied to them than to things that have 
 life and intelligence. 
 
 If I were convinced that it cannot be said, 
 in a plain, literal sense, that I am the cause 
 of my own actions, or that the Deity is the 
 cause of the universe — if I were convinced 
 that my actions, or the production of the 
 universe, are not effects, or that there must 
 be a cause of these effects distinct from the 
 agent, I should in this case agree to your 
 reasoning. 
 
 The rule of Latin syntax from which you 
 reason, seems, indeed, to suppose that all 
 causes are inanimate things, like means 
 and instruments ; but I desiderate better 
 authority. I am not sure but power and 
 agency are as often ascribed to inanimate 
 things as causation. Thus we speak of the 
 powers of gravity, magnetism, mechanical 
 powers, and a hundred more. Yet there is 
 a kind of power and agency which you 
 acknowledge to belong only to mind. 
 
 Your system, if I comprehend it, (which, 
 indeed, I am dubious about.) seems to go 
 upon the supposition that power and agency 
 belong onely to mind and that in language 
 causation never belongs to mind. If this 
 be so, you and I may, after all, differ only 
 about the meaning of words. What you 
 call an agent, and a being that has power, 
 that I call a cause with regard to every ex- 
 ertion of his power. 
 
 That which alone you call a cause, I 
 think is no cause at all in the strict sense of 
 the word ; but I acknowledge it is so in the 
 lax and popular sense.
 
 LETTERS TO DR JAMES GREGORY. 
 
 79 
 
 In these remarks I thought friendship 
 obHged nie to lay aside all regard to friend- 
 ship, and even to indulge a spirit of severity 
 that seems opposite to it. I hope you will 
 make allowance for this. For, in reality, 
 I have such an opinion of your judgment 
 and taste, that I cannot help suspecting my 
 own where thev dift'er. 
 
 XVII. 
 
 AN AMBIGUITY OF HUME — MEANINGS OF 
 WILL AND VOLITION — POWER. 
 
 Motive — SiXt U 
 
 27. [Page 21, published work.]— It 
 does not api)ear to nie, that the long pas- 
 sage quoted from IMr Hume's reconciling 
 project, is so full of ambiguous expressions 
 and hypothetical doctrine, as it is said to 
 be ; though I think it is very clearly shewn 
 to be full of weak reasoning. I think lie 
 does not confound a constant conjunc'ioii 
 with a necessary connection, but plainly dis- 
 tinguishes them ; affirming, that the fiist is 
 all the relation which, upon accurate reflec- 
 tion, we are able to perceive between cause 
 and effect ; but that mankind, by some pre- 
 judice, are led to think that cause and effect 
 have moreover a necessary connection ; 
 when at the same time they acknowledge 
 onelya constant conjunction betweenmotive 
 and action ; so far I see no obscurity or 
 ambiguity. The words cons/ant conjunction 
 and necessary connection, I think, are the 
 best that can be used to express the meaning 
 of each, and the difference between them. 
 At the same time, to suppose, without 
 assigning any reason for the su[iposition, 
 that the constant conjunction of cause and 
 effect leads men to believe a necessary con- 
 nection between them, but that the con- 
 stant conjunction ]!et\yccn motiee nnd action 
 lias no such efl'ect, appears to me very weak 
 and UMiihilosophical ; and this account of 
 the phenomenon of men's putting a differ- 
 ence between the relation of motive and 
 action, and the relation of cause and effect, 
 does not appear to me to deserve the epithet 
 you give it, of very ingenious. 
 
 The last part of the quotation, beginning 
 with — " Let any one <lejine a cause, tvil/iniit 
 comprehending," d.Q.,' I think has a distinct 
 
 • The whole sentence is as follows :— It Is from 
 Hume's " Itiquir> concernmR the Human Un.lor. 
 utandinj;," sect. viii. part I. prope fmem. " I.et any 
 one f/c/Snf a cause, without romprehendinp.ai a part of 
 the dtfiiiitioii, a necessary connection with its cffict ; 
 and let him«hew distinctly IheoiiKin of tlie idea, ex 
 pressed by the ilefinilion, and 1 shall readily give up 
 ihewhole controversy."— I)r Reid. in his remarks 
 on this pansaxe, would be ri(;ht, did Hume nuan 
 l)y necesfaiy connrcti-n, a really necessary con. 
 TKCIion, and not merely a feeling of necessity in 
 us, and that not a priori, but a poiteiiori— not the 
 
 meaning ; but that meaning is so imperti- 
 nent to his purpose, and so contrary to his 
 principles, that I cannot help thinking that 
 he meant to say the very contrary of what 
 he says ; and that the word without has slipt 
 into the sentence by an oversight of the 
 author or printer. For, does not he him- 
 self define a cause without comprehending, 
 as a part of the definition, a necessary con- 
 nection between the cause and the effect ? 
 Does he not maintain that we have no idea 
 of necessary connection ? He certainly 
 meant to say, that he would give up the 
 whole controversy, if any one could shew 
 that we have such an idea, and not to say 
 that he would give up the controversy, if 
 any one could give a definition of cause 
 without comprehending that idea. Were 
 I to comment upon this passage in the 
 Bentleian style, I would say dele zvithout, 
 meo periciilo. After all, how he should 
 think that the bulk of mankind have, without 
 reason, joyned the idea of necessary con- 
 nection to that of constant conjunction, in 
 the relation of cause and effect, when man- 
 kind have no such idea, I cannot account 
 for. 
 
 Of the Notion of Instrument. 
 
 66, &c. — I am not pleased with the three 
 different meanings you put upon the word 
 volition, nor do I think it ambiguous. Will 
 is indeed an ambiguous word, being some- 
 times put for the faculty of willing ; some- 
 times for the act of that faculty, besides 
 other meanings. But volition always sig- 
 nifies the act of willing, and nothing else. 
 Willingness, I think, is opposed to unwil- 
 lingness or aversion. A man is willing to 
 do what he has no aversion to do, or what 
 he has some desire to do, though perhaps 
 he has not the opportunity ; and 1 think 
 this is never called volition. 
 
 Choice or preference, in the proper sense, 
 is an act of the understanding ; but some- 
 times it is improperly put for volition, or 
 the determination of the will in things where 
 there is no judgment or preference ; thus, 
 a man who owes me a shilling, lays down 
 three or four equally good, and bids me take 
 which I clioo.se. I take one without any 
 judgment or belief that there is any ground 
 of preference — this is merely an act of will 
 that is a volition. 
 
 An effort greater or less, I think, always 
 accompanies volition, but is not called vo- 
 lition. There may be a determination of 
 will to do something to-morrow or next 
 week. This, though it be i>roperly an act 
 
 ofisprint? Ol'kilowl(d|;e, lull of blind habit. II ishciC 
 the part ol the sceplic, not to disprove the subjective 
 phtcnomcnon ol mcessity, but to shew that it is ille- 
 gitimate and objectively barren. — H.
 
 80 
 
 CORRESPONDENCE OF DR REID. 
 
 of win, is not called volition, because it has 
 a proper name of its own — we call it a reso- 
 lution or purpose ; and here the effort is 
 suspended till the purpose is to be ex- 
 ecuted. 
 
 I apprehend that, in dreaming, the effort 
 accompanies volitioii, as well as when we 
 are awake ; but in most persons the effort 
 in dreaming produces little or no motion 
 in the body, as is the case in palsy. When 
 a hound dreams, we see a feeble attempt to 
 move his limbs and to bark, as if he had the 
 palsj'. And a man dreaming that he cries 
 desperately for help, is often heard to make 
 a feeble attempt to cry. 
 
 PoWer. 
 
 16, &c, — I humbly think that my power 
 to ride or to walk, and the king's power to 
 call or to dissolve a parliament, are different 
 kinds, or rather different meanings of the 
 word power. In the former meaning, every- 
 thing depending upon my will is in my 
 power, and consequently my will itself ; for, 
 if I had not power to will, I could have no 
 power to do what depends upon my will. 
 In the second meaning, power signifies a 
 right by the law or by the constitution, 
 according to that maxim of law, Nihil pos- 
 sum quod jui e non jossum. 
 
 In another law sense, we say — It is part 
 of the king's prerogative that he can do no 
 wrong. The meaning of this is not that he 
 has no legal right to do wrong, for this may 
 be said of the meanest of his subjects ; but 
 it means that he cannot be accused or tried 
 for any wrong before any criminal judica- 
 ture. It is his prerogative, that he cannot 
 be called to account for any wrong. 
 
 7 1 , &c. — The doctrine delivered from page 
 71 to 76, I suspect very much not to be 
 just. If it be true, it is surely important, 
 and would make many difficulties instantly 
 to vanish, which the bulk of philosophers 
 have laboured in vain to resolve, and the 
 wiser part have reckoned to be insolvable. 
 It is so new and so contrary to all that 
 philosophers have taught and believed since 
 the days of Aristotle, that it ought to be 
 proposed andsupported with great modesty; 
 but, indeed, I cannot yet assent to it. 
 
 I have, for instance, the power of moving 
 my hand ; all the activity I am conscious 
 of exerting, is volition and effort to move 
 the hand ; the motion must begin some- 
 where. Suppose it begins at the nerves, 
 and that its being continued till the hand 
 be moved, is all mechanism. The first 
 motion, however, cannot be mechanism. 
 It follows immediately upon my volition and 
 effort. 
 
 Nor do I know how my volition and 
 effort to move my hand, produces a certain 
 
 motion in the nerves. I am conscious that 
 in this there is something which I do not 
 comprehend, though I believe He that made 
 me comprehends it perfectly. If I be struck 
 with a palsy, that volition and effort which 
 before moved my hand, is now unable to do 
 it. Is this owing to an inability to produce 
 the first motion ? or is it owing to some de- 
 rangement of the machine of the body ? I 
 know not. Nay, I am uncertain whether I 
 be truly and properly the agent in the first 
 motion ; for I can suppose, that, whenever 
 I will to move my hand, the Deity, or some 
 other agent, produces the first motion in my 
 body — which was the opinion of Male- 
 branche. This hypothesis agrees with all that 
 I am conscious of in the matter. I am like 
 a child turning the handle of a hand organ 
 — the turning of the handle answers to my 
 volition and eff'ort. The music immediately 
 follows ; but how it follows, the child knows 
 not. Were two or three ingenious children 
 to speculate upon the subject, who had never 
 seen nor heard of such a machine before, 
 perhaps one who had seen strange eff'ects of 
 mechanism, might conjecture that the 
 handle, by means of machinery, produced 
 the music : another, like Malebranche, 
 might conjecture that a musician, concealed 
 in the machine, always played when the 
 handle was turned. 
 
 We know as little how our intellectual 
 operations are performed as how we move 
 our own body. I remember many things 
 past ; but how I remember them I know 
 not. Some have attempted to account for 
 memory by a repository of ideas, or by traces 
 left in the brain of the ideas we had before. 
 Such accounts would appear ridiculous at 
 first sight, if we knew how the operation of 
 memory is performed. But, as we are 
 totally ignorant how we remember, such 
 weak hypotheses have been embraced by 
 sensible men. 
 
 In tiiese, and in innumerable cases that 
 might be mentioned, it seems to me to be 
 one thing to know that such a thing is, and 
 another to know how it is. 
 
 Perhaps you may have been led into the 
 mistake, if it be a mistake, by what you 
 say about definition in the note, p. 76. An 
 operation, or any other thing that is per- 
 fectly simple, cannot be defined — this is 
 true. Nor can it be explained by words to 
 a man who had not the conception of it be- 
 fore ; for words can give us no new simple 
 conceptions, but such only as we had before, 
 and had annexed to such words. 
 
 Thus, if a man born blind asks me what 
 a scarlet colour is, the question, I think, is 
 not impertinent, or nugatory, or absurd; but 
 I can only answer him, that, though I know 
 perfectly what a scarlet colour is, it is im- 
 possible to give him a distinct conception of 
 it unless he saw. But, if he asks me how
 
 LETTERS TO DIl JAMES GREGORY. 
 
 81 
 
 my volition and effort moves my band, I 
 not onely cannot satisfy him, but am con- 
 scious that I am ignorant myself. We both 
 know that there is a constant conjunction 
 between the vohtion and tlie motion, when 
 I am in liealth, but how tliey are connected 
 I know not, but should think myself much 
 wiser than I am, if I did know. For any- 
 thing I know, some other being may move 
 my hand as often as I will to move it. The 
 volition, I am conscious, is my act ; but I 
 am not conscious that the motion is so. I 
 onely learn from experience that it always fol- 
 lows the volition, when I am in sound health. 
 
 Activity. — Sect. 1. 
 
 P. 24, &c The distinction between the 
 
 two kinds of active verbs here marked, ap- 
 pears no less clearly when they are used in 
 the passive voice. To he known, to be be- 
 lieved. &C-, imply nothing done to the things 
 known or believed. But to be tvounded, to 
 be healed, implies something done to the 
 wounded or healed. A scholastick phil(iSO- 
 pher would say that to be ivounied, belongs 
 to the category of passion ; but to be kiiou n. 
 belongs to none of the categories — being only 
 an extermd denomination. Indeed, however 
 grammarians might confound those two 
 kinds of active verbs, the scholastick philo- 
 sophers very properly distinguished the acts 
 expressed by them. They called the acts 
 expressed by the first kind immanent acts, 
 and those expressed by the second kind, 
 transitive acts. Immanent acts of mind are 
 such as produce no change in the object. 
 Such are all acts of understanding, and even 
 some that may be called voluntary — such as 
 attention, deliberation, purpose. 
 
 Activity — Sect. 2. 
 
 P. 43. — If my memory does not deceive 
 me, Charlevoix, in his history of Canada, 
 says, that, in the Huron language, or in some 
 language of that country, there is but one 
 word for both the .sexes of thehuman species, 
 wliich word has two genders, not a mascu- 
 line and feminine— for there is no such dis- 
 tinction of genders in the language— but a 
 a noble and an ignoble gender : the ignoble 
 gender signifies not a woman, thougli wo 
 improperly translate it so. It signifies a 
 coward, or a good-for-nothing creature of 
 either sex. A woman of distingui.shcd 
 talents that create respect, is always of tlie 
 noble gender. I know not whether it lie 
 owing to something of this kind in the 
 (ifielic langua^jc, that a Iligiilander, who 
 Las got onely a little broken Kngli-'h, modestly 
 
 takes the feminine gender to himself, and, 
 in place of saying / did so, says, her own self 
 did 40. ..... . 
 
 As to the mathematical reasoning on 
 motive. Section 2, to prove that the relation 
 of motive and agent is very different from 
 that of a physical cause to its efl'ect, I think 
 it just and conclusive ; and that it isa good 
 argument ad homhiem, against the scheme 
 of Necessity held by Hume, Priestley, and 
 other modern advocates for Necessity, who 
 plainly make these two relations the same. 
 Mr Hume holds it for a maxim no less ap- 
 plicable to intelligent beings and their ac- 
 tions, than to. physical causes and their 
 effects, that the cause is to be measured by 
 the efl'ect. And from this maxim he infers, 
 or makes an Epicurean to infer, that we 
 have reason to ascribe to the Deity just as 
 much of wisdom, power, and goodness, as 
 appears in the constitution of things, and 
 no more. 
 
 The reasoning mthe papers on activity, to 
 shew that the relation between an agent and 
 hisaction is, in the structureof language, dis- 
 tinguished from the relation between a cause 
 and its effect, is, I think, perfectly just when 
 cause is taken in a certain sense ; but I am 
 not so clear that the word cause is never, 
 except metaphorically or figuratively, taken 
 in any other sense. You will see my senti- 
 ments about that word in two chapters of my 
 " Essay on the Liberty of Moral Agents," 
 now in your hands. If I had seen your 
 papers before I wrote those two chapters, 
 perhaps I would have been more explicit. 
 However, they will save you and me the 
 trouble of repeating here what is there said. 
 
 I think, after all, the difference between 
 you and me is merely about the use of a 
 word ; and that it amounts to this — whether 
 the wordcause, and the corresponding words 
 in other languages, has, or has not, from the 
 beginning, been used to express, without a 
 figure, a being that produces the effect by 
 his will and power. 
 
 I see not how manldnd could ever have 
 acquired the conception of a cause, or of 
 any relation, beyond a mere conjunction in 
 time and place between it and its effect, if 
 they were not conscious of active exertions 
 in themselves, by which effects are pro- 
 duced. This seems to me to be the origin 
 of the idea or conception of production. 
 
 In the grammar rule, causa, modus et 
 instrurnentum, &c., the word cause is taken 
 in a limited sense, which is explained by 
 the words conjoyned wkh it. Nor do I si e 
 that any part of the rule would be lost if 
 the word causa had been altogether left out. 
 Is not everything wliich you would call a 
 cause a mean or an instrument ? ^fay not 
 everything to whicli the rule applies bo 
 called a mean or an instrument ? But surely 
 many things are called causes that aro 
 
 a
 
 82 
 
 CORRESPONDENCE OF DR REID. 
 
 neither means nor instruments, and to which 
 the rule does not apply. 
 
 You know that Aristotle, who surely 
 understood Greek, makes four kinds of 
 causes — the efficient, the matter, the form, 
 and the end- I think the grammar rule 
 applies to none of these ; for they are not 
 in Latin expressed by an oblative without 
 a preposition. 
 
 That nothing can happen without a cause, 
 is a maxim found in Plato, in Cicero, and, I 
 believe, never brought into doubt till the 
 time of D. Hume. If this be not under- 
 stood of an efficient cause, it is not true of 
 any other kind of cause ; nor can any reason 
 be given why it should have been universally 
 received as an axiom. All other causes 
 suppose an efficient cause ; but it supposes 
 no other ; and, therefore, in every enumer- 
 ation of causes, it is made the first ; and 
 the word cause, without any addition, is put 
 to signify an efficient cause ; as in that of 
 Cicero, (which I quote only from memory,) 
 " Itaque non est causa quod cuiqne ante- 
 cedif, sed quod cuxque efficicnter ante- 
 eedit." 
 
 XVIII. 
 
 ON THE TERMS, PHILOSOPHICAL NECESSITY, 
 AND NECESSARIAN — ON DETERMINATION 
 BY STRONGEST MOTIVE — REPROACH OP 
 MALA FIDES — CONSCIOUSNESS OF LIBERTY 
 
 — ARGUMENTUM PIGRUM, &C IN A PAPER 
 
 ENTITLED^ 
 
 Remarks* 
 
 Page 2. — " Philosophical Necessity.^^ — 
 This, I think, is an epithet given to the 
 doctrine of Necessity by Dr Priestley only ; 
 and I do not see that he deserves to be fol- 
 lowed in it. The vulgar have, from the 
 beginning of the world, had the conception 
 of it as well as philosophers. Whether they 
 ground it upon the influence of the stars, 
 or the decrees of fate, or of the gods, or 
 upon the influence of motives, it is necessity 
 still. I have often found the illiterate vul- 
 gar have recourse to it to exculpate their 
 own faults, or those of their friends, when 
 no other excuse could be found. It lurks 
 in their minds as a last shift to alleviate the 
 pangs of guilt, or to soften their indignation 
 against those whom they love.-f But it is not 
 admitted on other occasions. Dr Priestley 
 by this epithet no doubt wished it to pass 
 for a profound discovery of philosophy ; but 
 
 * On the " Essay." Somepages correspond to the 
 published work, others do not. The " Essay ' was, 
 therefore, probably printed but in proof. — H. 
 
 + Thus Agamemnon : — '£yu h' oix aiiii; ilf/.i. 
 
 I know no claim it has to be called philoso- 
 phical. 
 
 In other places, you use another of Dr 
 Priestley's words — the Necessarians. I see 
 no reason for adding this wx)rd to our lan- 
 guage, when Fatalists might do as well. 
 Sometimes I think you call them the Philn- 
 sophers indefinitely. I don't lilce this 
 neither. Fatalism was never so general 
 among philosophers, nor so peculiar to them, 
 as to justify it. 
 
 P. 27 — In my " Essay on Liberty" I 
 have censured the defenders of Necessity for 
 grounding one of their chief arguments upon 
 this as a self-evident axiom. That the strong- 
 est motive always determinrs the agent, while 
 no one of them, as far as I know, has offered 
 to explain what is meant by the strongest 
 motive, or given any test by which we may 
 know which of two contrary motives is the 
 strongest ; without which the axiom is an 
 identical proposition, or has no meaning at 
 all. I have offered two tests of the strength 
 of motives — according as they operate upon 
 the will immediately, or upon the under- 
 standing — and endeavoured to shew that the 
 maxim is not true according to either. 
 
 ■ • • • 
 
 P. 72. — The want of sincerity or bona 
 fides, in a large body of men, respected and 
 respectable, is a very tender place, and can- 
 not be touched with too much delicacy. 
 Though you were sure of being able to de- 
 monstrate it, I am afraid it may be taken as 
 an insult, which even demonstration cannot 
 justify. Your not making the conclusion 
 general, for want of a sufficiently extensive 
 information, will not satisfy, because it seems 
 to extend the conclusion as far as your 
 observation has extended, and because the 
 reasons on which you ground your con- 
 clusion seem to extend it to all fatalists 
 who can draw a conclusion from premises. 
 If David Hume, or any other person, has 
 charged those who profess to believe men to 
 be free agents with insincerity, I think he 
 did wrong, and that I should do wrong in 
 following the example. 
 
 But, setting apart the consideration of 
 hienseance, I doubt of the truth of your 
 conclusion. If human reason were perfect, 
 I think you would be better founded ; but 
 we are such imperfect creatures, that I fear 
 we are not exempted from the possibility of 
 swallowing contradictions. Could you not 
 prove with equal strength that all bad men 
 are infidels ? Yet I believe this not to be 
 true. 
 
 In page 76, you speak of our having a 
 consciousness of independent activity. I 
 think this cannot be said with strict pro- 
 priety. It is only the operations of our 
 own mind that we are conscious of. Ac- 
 tivity is not an operation of mind ; it is a
 
 LETTERS TO DR JAMES GREGORY. 
 
 83 
 
 power to act. We are conscious of our 
 volitions, but not of the cause of them. 
 
 I thiuk, indeed, that we have an early 
 and a natural conviction that we have power 
 to will this or that ; that this conviction 
 precedes the exercise of reasoning ; that it 
 is implyed in all our deliberations, purposes, 
 promises, and voluntary actions: and I have 
 used this as an argument for liberty. But 
 I think this conviction is not properly called 
 consciousness. 
 
 I truly think that a fatalist who acted 
 agreeably to his belief would sit still, like a 
 passenger in a ship, and suffer himself to be 
 carried on by the tide of fate ; and that, 
 when he delil3erates, resolves, promises, or 
 chuses, he acts inconsistently with his be- 
 lief. But such mconsistencies, I fear, are 
 to be found in life ; and, if men be ever con- 
 vinced of them, it must be by soothing words 
 and soft arguments, which ludunt cir- 
 cum prcBcordia ; for the force of prejudice, 
 joyned with that of provocation, will shut 
 the door against all conviction. 
 
 I humbly think, therefore, that it will be 
 prudent and becoming to express less con- 
 fidence in your mathematical reasonings, 
 though I reallybelieve them to be just upon 
 the hj-pothesis you combat. Fatalists will 
 think that, when you put the issue of the 
 controversy solely upon the experiments, 
 you treat them like children. No fatalist 
 will contend with you upon that footing, 
 nor take it well to be challenged to do so ; 
 and I think you have a good plea with any 
 man who disputes the strength of your ma- 
 thematical reasoning, to prove that the 
 relation between motives and actions is 
 altogether of a different kind, and subject to 
 different laws from that between physical 
 causes and their effects. 
 
 XIX. 
 
 ON VULGAR NOTION OF NECESSARY CONNEC- 
 TION — INADVERTENCY OF HUME — REId's 
 REFUTATION OF IDEAS — REId's USE OF THE 
 WORD CAUSE —INERTIA, PASSIVITY, STATE, 
 OF MIND — AND SUNDRY OBSERVATIONS ON 
 THE NECESSITARIAN CONTROVERSY — IN A 
 I'APER ENTITLED 
 
 Remarks on the Essay. 
 
 Page 2.3 I am apt to think even the 
 
 vulgar have the notion of necessary con- 
 nection, and that they perceive it in arith- 
 metical and mathematical axioms, though 
 they do not speculate about it ; nor do they 
 perceive it between physical causes and 
 their effects. Docs not every man of com- 
 mon sense perceive the ridiculousness of 
 
 that complaint to the gods, which one of 
 the heroes of the " Dunciad" makes — 
 
 -" And am I now fourscore? 
 
 As publikhcd. — H. 
 
 Ah! why, ye gods, should twoand two make four ?" 
 
 But is it not remarkable that Mr Hume, 
 after taking so much pains to prove that we 
 have no idea of necessary connection, should 
 impute to the bulk of mankind the opinion 
 of a necessary connection between physical 
 causes and their effects ? Can they have 
 this opinion without an idea of necessary 
 connection ? 
 
 33 — The passage here quoted from Mr 
 Hume is, indeed, so extraordinary, that I 
 suspect an error in printing, and that the 
 word without has been put in against his 
 intention, though I find it in my copy of his 
 essays, as well as in your quotation. For 
 how could a man who denies that we have 
 any idea of necessary connection, defy any 
 one to define a cause without comprehending 
 necessary connection ? He might, consist- 
 ently with himself, have defied any one to 
 define a cause, comprehending in the defi- 
 nition necessary connection ; and at the 
 same time to shew distinctly the origin of 
 the idea expressed by the definition. How 
 could he pledge hunself to give up the con- 
 troversy on the condition of getting such a 
 definition, when, as you observe, he had 
 given two such definitions himself? If 
 there be no error of the press, we must 
 say, Aliquando bonus dormitat Humiiis." 
 
 34 and 35 — You observe justly and perti- 
 nently, that "the intelligible and consistent 
 use of a word shews that the speaker had 
 some thought, notion, or idea, correspond- 
 ing to it." Idea is here put for the mean- 
 ing of a word, which can neither be true nor 
 false, because it implies neither affirmation 
 nor negation. But in the same paragraph 
 it is supposed that this idea may be im- 
 proper, groundless, and to be given up. 
 This can onely be applied to idea, taken 
 in another sense — to wit, when it implies 
 some affirmation or negation. I know this 
 ambiguity may be found in Locke and Hume ; 
 but I think it ought to be avoided. 
 
 36. — " Or the philosophical doctrine of 
 ideas." If, an hundred years after this, the 
 philosophical doctrine of ideas bo as little 
 regarded as the Vortices of Des Cartes are 
 at this day, they may then be coupled in 
 the manner you here do. But at present, 
 though I am proud of your oj)inioii, that 
 that doctrine must be given up, T think it 
 is expressed in a way too assuming with 
 regard to the i)ublick. 
 
 40 I know of no i)hiloHophcr who makes 
 
 the word cnu.sc extend solely to the giving 
 of existence. 
 
 44. Dr Reid agrees with the author of 
 the Essay, that the word cause ought to bo 
 
 • Sec note at page 79.— H. 
 o2
 
 84 
 
 CORRESPONDENCE OF DR REID. 
 
 used in the most common sense." But 
 one sense may be the most common in 
 one science, and another in others. He 
 thinks that, in theology and in metaphysicks, 
 the most common sense is that of agent or 
 efficient cause ; and for this he thinks he 
 has the authority of Des Cartes, Locke, 
 Dr Clarke, Bishop Butler, and many others. 
 In physicks, and in all its branches, medi- 
 cine, chymistry, agriculture, the mechani- 
 cal arts, &c., he thinks the most common 
 meaning of cause is Hume's notion of it — 
 to wit, something which goes before the 
 effect, and is conjoyned with it in the course of 
 nature. As this notion is vague and popular, 
 philosophers, when they would speak more 
 precisely of a cause in physicks, mean by 
 it some law of nature, of which the phoeno- 
 menon called the effect is a necessary 
 consequence. Therefore, in writings of 
 the former knid, he would think himself 
 warranted to use the word cause, witliout 
 addition in the first of these senses ; and, if 
 he had occasion to use it in the last sense, 
 he would call it physical cause. In writings 
 of the last kind, he thinks it may, with pro- 
 priety, be used without addition in the last 
 sense ; and if, in such writings, it be used 
 in the first sense, he would have it called 
 the efficient cause. But the additions of 
 efficient and physical, he does [not] conceive 
 as denoting two species of the same genus, 
 
 t This is in reference to what Dr Gregory says of 
 the meaning attached by Keid himself to the word 
 cause. The passage is as follows : — " As little could 
 he (Hume) have in view the meaning expressed in 
 the third query, in which meaning Ur Reid (I own 
 I think with too little regard to the common use and 
 application of the word cause) hath employed it in 
 arguing this question ; (• Essays on the Active 
 V ovists,' passim-,) as where lie says, after admitting 
 that everything must have a cause, that, in the case 
 of voluntary actions, it is not the motive, but the 
 person, that is the cause of them This meaning of 
 the term cause — to wit, a being having power (and 
 optional or discretionary powei) to produce or not to 
 produce a certain change — is not only evidently dif. 
 ferent from Mr Hume's, but comple'ely repugnant to 
 his whole system. We may therefore set it aside 
 too." 
 
 It is necessary to quote the queries to which refer- 
 ence is made in the preceding passage. They are 
 thcio : — " It might reasonably be asked — (1') Is the 
 word cause employed in that general fourfold sense 
 mentioned by Aristotle, and applied equally to the 
 essence or form of a being, to the matter of it, to the 
 efficient or agent, and to the motive, or purpose, or 
 final cause? Or (2°) is it employed in its more 
 common and limited acceptation, as generally used in 
 physics, and, indeed, in popular discourse, as when we 
 say, ' Heat is the cause of expansion,' excluding all 
 the other meanings of it, and particularly that of the 
 agent? Or (:? ) is it employed in that more limited 
 sense in which it hath been defined and used by 
 several philosophers, to denote exclusively the agent, 
 in contradistinction to the physical cause ? Or (4^) 
 is it used to express the vague notion insinuated by 
 Aristotle's « e| oui comprehending all these alre.idy 
 mentioned, and many more ? For example — what the 
 parts are to the whole, what a right angle in a tri. 
 angle is to the proportion between the squares of the 
 sides of it, what the absence of a pilot is to a ship, 
 wreck, what the seed is to a plant, what a father is 
 to his son, what the removal of an opposing cause is 
 to any event or effect, &c. Ike." — H. 
 
 but as distinguishing two different meanings 
 of the same ambiguous word. 
 
 You have good reason to dispute the 
 maxim about causes, as laid down by Mr 
 Hume, in whatever sense he takes the word 
 cause. It is a maxim in natural theology, 
 universally admitted, that everything that 
 begins to exist must have a cause, meaning 
 an efficient cause ; and from this maxim we 
 easily deduce the existance of a Being who 
 neither had a cause nor a beginning of ex- 
 istance, but exists necessarily. Physicks, 
 in all its branches, is conversant about the 
 phenomena of nature, and their physical 
 causes ; and I think it may be admitted as 
 a maxim that every phenomenon of nature 
 has a physical cause. But the actions of 
 men, or of other rational beings, are not 
 phenomena of nature, nor do they come 
 within the sphere of physicks. As little is 
 a beginning of existance a phenomenon of 
 nature. 
 
 • ••••*• 
 
 Page 154 — " Expressly excluding from 
 the meaning of the phrase,"" 4 c, to the end of 
 the paragraph. • My remark upon this para- 
 graph I think more important than any 
 other I have made on the Essay; and, there- 
 fore, I beg your attention to it. 
 
 Inertia of mind seems to be a very pro- 
 per name for a quality which, upon every 
 system of Necessity, must belong to the 
 mind. It is likewise very proper to explain 
 tlie meaning of that term when appUed to 
 the mind. 
 
 But when you " expressly exclude from 
 the meaning of the phrase, the circumstance 
 of mind remaining or persevering in any 
 state into which it once gets," I wish you 
 to consider very seriously whether this con- 
 cession be not more generous than just ; and, 
 if it be not just, whether by making it, you 
 
 » The whole passage referred~to is as follows :— 
 "I have occasion often to consider the supposed want 
 of any such attribute of mind [viz.. Power] as this is 
 the fundamental principle of thedoctrineof necessity. 
 And, for the sake of brevity, and the opposition to 
 what has been often termed Activity and Force of 
 Mind, I call it the Inertia of Mind; limiting, how- 
 ever, the signification of the phrase, to denote merely 
 the incapacity of acting optionally or discretionally 
 without motives, or in opposition to all motives, or 
 in any other way but just according to the motives 
 applied, and expressly excluding from the meaning 
 of the phrase the circumstance of mind rem;iiningor 
 persevering in any ktate into which it once get.s, as 
 body does in a state, either of rest or of uniform 
 progressive rectilinear motion, into which it is once 
 put. Such permanency of state does not appear to be 
 any part of the constitution of the human mind, with 
 lespect to any of its operations. Sensation of t very 
 kind— memory, imagination, judgment, emotion, or 
 passion, volition, and involuntary effort — all appear 
 to be transient conditions, or attributes of mind ; 
 which, of their own nature, independently of any 
 cause applied, pass away or come to an end. And 
 this I conceive to be one of the most general circnra. 
 stances of distinction between mere sia'eor condition, 
 which is prcdicable ol mind as well as body, (as, for 
 example, madness, idiotism, vivacity, dulncss, pecu. 
 liar genius, wisdom, knowledge, virtue, vice,) and 
 those things which are termed acts or operations of 
 mind or thought." — H.
 
 LETTERS TO DR JAMES GREGORY. 
 
 85 
 
 do not much weaken the force of a great 
 part of your subsequent reasoning. 
 
 The justice of the concession is not evi- 
 dent to me. To be merely pissive, and to 
 remain in the stale i»lo which it is put, seem 
 to signify the same thing ; as, on the other 
 hand, to be active, and to have poiver to 
 change its own state, have the same meaning. 
 If the mind be passive onely, all its changes 
 are phenomena of nature, and therefore be- 
 long to the science of physieks, and require 
 a physical cause, no less than does the 
 change of direction or of velocity in a moving 
 body. 
 
 Of all things that belong to the mind, its 
 acts and operations are the onely things 
 which have any analogy to motion in a body. 
 The same analogy there is between the 
 ceasing of any act or operation and the 
 ceasing of motion. If, therefore, from mere 
 inactivity, the body, once put in the state of 
 motion, continues or perseveres in that 
 state, why should not a mind, which is 
 equally inactive, being once ]iut in the state 
 of action or operation, continue in that state ? 
 
 You say, " Such permanency of state 
 does not appear to be the constitution of 
 the mind in any of its operations." I grant 
 this. But the question is not, " What really 
 is its constitution ?" but " What would be 
 its constitution if it were as inert and in- 
 active as body is ?" To admit this want of 
 permanency is to admit that the mind is 
 active in some degree, which is contrary to 
 the supposition. 
 
 The reason why madness, idiotism, &c., 
 are called states of mind, while its acts and 
 operations are not,* is because mankindhave 
 always conceived the mind to be passive in 
 the former and active in the later. But on 
 the system of Necessity, this distinction has 
 no place. Both are equally states, onely 
 the first are not so frequently changed as 
 the last. 
 
 If the concession be just and consistent 
 with necessity, it must be granted, wliat- 
 ever be its consequences ; but I apprehend 
 the consequences will deeply affect your essay. 
 
 For, first, it contradicts what you have 
 said, page .33G, and, perhaps, in several 
 other places, that, " according to Mr 
 Hume's doctrine, a living person, in relation 
 to motives and actions, is precisely in the 
 situation of an inanimate body in relation to 
 projection and gravity." If an inanimate 
 body had not the quality of persevering in 
 its state of motion, the effect of projection 
 and gravity upon it would be very different 
 from what it is with that quality. 
 
 Secondly, by this concession, your reason- 
 ing from the laws of motion and their cor- 
 ollaries, is much weakened j for those laws 
 
 • TTie term State has, more esi^ocially of late years, 
 and principally liy Nccenilarian priilimrpphcrn, been 
 •pplled 10 ali modifications of mind incliitl-rently. — ii. 
 
 and corollaries are founded on the supposi- 
 tion that bodies persevere in the state of 
 motion as well as of rest ; and, therefore, 
 are not properly applied to a being which 
 has not that quality. Indeed, perseverance 
 in its state is so essential to inertia, that it 
 will be thought unjustifiable to apply that 
 name to what you acknowledge does not 
 persevere in its state. And you will, 
 perhaps, be charged with giving an invi- 
 dious epithet to the mind, which, by 
 your own acknowledgment, is not due, and 
 then reasoning from that epithet as if it 
 were due. 
 
 ■ • • • • 
 
 226. — In the style of physieks, to carry a 
 letter in the direction A B, and to carry a 
 letter from A to the point B, are different 
 things. Any line parallel to A B, is said 
 to be in the direction A B, though it can- 
 not lead to the point B. 
 
 The case, therefore, here put, is, that the 
 porter is offered a guinea a-mile to carry a 
 letter from A to the point B, and half-a- 
 guinea a-mile to carry a letter, at the same 
 time, from A to the point C. And both 
 motives must necessarely operate according 
 to their strength. I truely think it impos- 
 sible to say how the porter would act upon 
 these suppositions. He would be in an in- 
 extricable puzzle between contrary actions 
 and contrary wills. 
 
 One should think that the two motives 
 mentioned, would conjoyn their force in the 
 diagonal. But, by going in the diagonal, 
 he loses both the guineas and the half- 
 guineas ; this is implied in the offer, and is 
 a motive not to go in the diagonal, as strong 
 as the two motives for going in it. By the 
 force of the two motives, he must will to go 
 in the diagonal ; by the force of the thii-d, 
 he must will not to go in the diagonal. 
 
 You pretend to demonstrate that he 
 must go in the diagonal willingly. I think 
 it may be demonstrated, with equal force, 
 that he must will not to go in the diagonal. 
 I perceive no error in either demonstration ; 
 and, if both demonstrations be good, what 
 must be the conclusion ? The conclusion 
 must be, that the supposition on which both 
 demonstrations are grounded nmst be false — 
 I mean the supposition that motives are the 
 physical causes of actions ; for it is possible, 
 and often happens, that, from a false sup- 
 position, two contradictory conclusions may 
 be drawn ; but, from a true supposition, it 
 it impossible. 
 
 I think it were better to omit the case 
 stated toward the end of this page,* because 
 I think it hardly possible to conceive two 
 motives, which, lieing conjoynod, shall have 
 an analogy to a projectile and ceiitripctal 
 force conjoyncil ; and your concession, that 
 
 ♦ This has heen done— H.
 
 86 
 
 CORRESPONDENCE OF DR REID. 
 
 the effect of a motive is not permanent, 
 adds to the difficulty. A projectile force 
 requires a cause to begin it, but it requires 
 no continuance of the cause — it continues 
 by the inertia of matter. A centripetal force 
 is the effect of a cause acting constantly ; 
 and the effect of that cause must bear some 
 proportion to the time it acts. Diminish 
 the time, in infinitum, and the effect of a 
 centripetal force is diminished, in infinitum ; 
 so that, in any one instant of time, it bears 
 no proportion to a projectile force ; and, 
 what makes the effect of a centripetal, in a 
 given time, to be capable of comparison with 
 a projectile, force, is, that the effects of the 
 centripetal force, during every instant of the 
 time, are accumulated by the inertia of mat- 
 ter, and all, as it were, brought into one 
 sum. Now, how can you conceive two 
 motives, which have a difference and a re- 
 lation to each other, corresponding to the 
 difference and the relation of these two kinds 
 of force ? Both kinds of force suppose the 
 permanency of motion once acquired, and, 
 I think, cannot be distinctly conceived, or 
 their effects ascertained, without that sup- 
 position. 
 
 337 — Upon the scheme of Necessity, 
 considered in this section, it must be mam- 
 tained, that there is some unknown cause 
 or causes of human actions, besides motives, 
 which sometimes oppose motives with greater 
 force, sometimes produce actions without 
 motives ; and, as there are no causes but 
 physical causes, all actions must be neces- 
 sary, whether produced by motives or by 
 other physical causes. This scheme of 
 Necessity appears, indeed, to me more 
 tenable than that of Hume and Priestley ; 
 and I wonder that Mr Hume, who thought 
 that he had proved, beyond doubt, that we 
 have no conception of any cause but a physi- 
 cal cause, did not rest the doctrine of Neces- 
 sity upon that principle solely. Unknown 
 causes would have afforded him a retreat in 
 all attacks upon his system. That motives are 
 the sole causes of action, is onely an outwork 
 in the system of Necessity, and may be given 
 up, while it is maintained that every action 
 must have a physical cause ; for physical 
 causes of all human actions, whether they 
 be known or unknown, are equally inconsist- 
 ent with Uberty. 
 
 342. — A physical cause, from its nature, 
 must be constant in its effects, when it exists, 
 and is applied to its proper object. But of un- 
 known causes, the existence and the applica- 
 tion may depend upon a concurrence of acci- 
 dents, which is not subject to calculation, or 
 even to rational conjecture. So that, I 
 apprehend, the existance of such causes can 
 never be demonstrated to be contrary to 
 matter of fact. Unknown causes, like oc- 
 cult qualities, suit every occasion, and can 
 never be contradicted by phsenomena ; for, 
 
 as we cannot, a priori, determine what shall 
 be the effects of causes absolutely unknown ; 
 so it is impossible to prove, of any effect 
 whatsoever, that it cannot be produced by 
 some unknown physical cause or causes. 
 
 The defects of this system of Necessity, I 
 think, are these two : — first, it is a mere 
 arbitrary hypothesis, brought to prop a weak 
 side in the hypothesis of Necessity ; and, 
 secondly, it is grounded on the supposition 
 that every event must have a physical cause, 
 a supposition which demonstrably termin- 
 ates in an infinite series of physical causes, 
 every one of which is the effect of a physical 
 cause. 
 
 If the doctrine opposed in this IGth sec- 
 tion be as it is expressed, page 338 — that, 
 though the connection of motive and action 
 is but occasional, the volitions and actions 
 of men are absolutely produced by motives 
 as physical causes — this doctrine I take to 
 be a contradiction in terms, and unworthy 
 of confutation. It maintains that men are 
 absolutely determined by motives, and yet 
 onely occasionally determined by motives — 
 which, if I understand it right, is a contra- 
 diction. 
 
 351. The case supposed in this page seems 
 perfectly similar to that of page 226 ; the 
 same reasoning is applied to both Should 
 not the conclusion be the same in both ? 
 
 431. — Is there not some inaccuracy in the 
 reasoning in this and the next page ? I take 
 X and Y to represent equal motives to action, 
 and V a motive to inaction, which equally 
 opposes both. If this be so, the motives to 
 the opposite action stand thus : X — V -{- Z 
 on one side, and Y — V on the other. Then 
 there will be a preponderancy on the side 
 of X as long as X and its equal Y is greater 
 than V ; and if X be withdrawn on one 
 side, and Y on the other, we shall have 
 — V -J- Z opposed to — V, In this case, if Z 
 be equal to V, the motives to act and not 
 to act on the side of Z will be equal ; if Z 
 be less than V, the strongest motive will be 
 for inaction ; and if Z be greater than V, 
 there will be a preponderating motive to act 
 on the side of Z. 
 
 As to the style in general, the only fault 
 I find is, that it abounds too much in long 
 and complex sentences, which have so many 
 clauses, and so much meaning, that it is 
 difficult to carry it all from the beginnhig to 
 the end of the sentence. The reader's un- 
 derstanding should have gentle exercise, but 
 not hard labour, to comprehend the author's 
 meaning. I dislike a style that is cut down 
 into what the ancients called commas of a 
 line or half a line. This, like water falling 
 drop by drop, disposes one to sleep. But I 
 think you rather go into the contrary ex- 
 treme. Your friend. Lord Bacon, says, 
 " A fluent and luxuriant speech becomes 
 youlh well, hut not age." I believe he had
 
 LETTERS TO DR JAMES GREGORY. 
 
 87 
 
 in his view a rhetorical speech, and not the 
 lene el temperalum iticendi genus, which, 
 iu Cicero's judgment, best suits philosopliy. 
 
 XX. 
 
 ON A NOVEL USE OF THE WORD MOTIVE — 
 CAUSALITY OF MOTIVES, &C. 
 
 1793. 
 
 Dear Sir — I received Mr Crombie's 
 Essay* on Friday the 11th, at night, and 
 have read it twice, though interrupted by 
 the removal of my family to the college. 
 If this be Mr Crombie's first essay in con- 
 troversy, I think he shews no mean talent, 
 and may in time become an able champion. 
 
 He has done me particular honour in 
 directing so great a part of the book against 
 me ; yet, though I read the work without 
 prejudice, my opinion is not changed iu any 
 point of the controversy. 
 
 He has strengthenedhis defensive armour 
 by extending the meaning of the word mo- 
 tive. I understood a motive, when applied 
 to a human being, to be that for the sake of 
 which-f- he acts, and, therefore, that what he 
 never was conscious of, can no more be a 
 motive to determine his will, than it can be 
 an argument to convince his judgment. 
 
 Now, I learn that any circumstance 
 arising from habit, or some mechanical in- 
 stinctive cause, may be a motive, though it 
 never entered into the thought of the agent. 
 
 From this reinforcement of motives, of 
 which v.'e are unconscious, every volition 
 may be supplied with a motive, and even a 
 predominant one, when it is wanted. 
 
 Yet this addition to his defensive force 
 takes just as much from his offensive- 
 
 The chief argument for Necessity used 
 by D. Hume and Lord Kames is, that, from 
 experiance, it appears that men are always 
 determined by the strongest motive. This 
 argument admits of much embellishment by 
 a large and pleasant induction. 
 
 * IJr Crcimbie, the well-knowr. author of the 
 " Gymnasium," and other able works, published an 
 " Essay on Philosophical Necessity," Londoti, I79i, 
 in which l)r (ireijory's reasoning is assailed with 
 much acrimony and considerable acuteness. It is 
 to this trcati-c that Iteiii's remarks apply. There 
 sub8(quently a|'pearcd, " Letters from Dt James 
 CircRory of Edinburgh, in Defence of his Kesay on the 
 Diffi-'rcncc 01 the .-elation between Motiveand Action, 
 and that of Cause and Kfleclin Physic*; with Replies 
 by the llev. Alexander Crombie, Ll,. IJ. ;" London, 
 Ihl'J. It is much to be regretted, that Dr Gregory 
 did not find leisure to complete his " Answer to 
 Messrs Crombie, Prieslley, and Co.;" of which 512 
 pages have been printed, but are slill unpublished. 
 
 t This is Aristolle's definition {to'itixa, ov) of end 
 or final cauf; and, as a synonyme for end or final 
 ca'ise, the term motive h.id been long exclusively 
 ctijploye<l. There are two schemes of Necessity — 
 the Neces'i'ation by etficcent— the Necesfitation by 
 final causes, 'the former i> brute or blind I'atc; the 
 l.-.tter rational Ueterniinism. '1 IioukIi their practiciii 
 ri-«ults be the hanie, ihev ought to be carefidly dis- 
 tinguished in theory. '-H. 
 
 After these two authors had exhausted 
 their eloquence upon it, Mr Crombie adds 
 his, from page 27 to 39. Now, if motives 
 we are unconscious of be the cause of many 
 actions, it will be impossible to prove from 
 experiance, that they are all caused by mo- 
 tives. For no experiment can be made 
 upon motives we are unconscious of. If, 
 on the contrary, all our actions are found 
 by experiance to proceed from motives 
 known or felt, tliere is no work left for the 
 unknown, nor any evidence of their exist- 
 ance. I apprehend, therefore, Mr Crombie 
 must either keep by the old meaning of 
 motive, or give up this argument for Neces- 
 sity taken from experiance. 
 
 But he lays the main stress, as Dr Priestley 
 likewise has done, upon another argument. 
 It is, that a volition not determuied by mo- 
 tives, is an uncaused effect, and therefore 
 an absurdity, a contradiction, and the greatest 
 of all absurdities. 
 
 I think, indeed, it is in vain to reason upon 
 the subject of Necessity pro or con, till this 
 point be determined ; for, on the one side, to 
 what purpose is[it] to disprove by argument 
 a proposition that is absurd ? On the other 
 side, demonstration itself cannot prove that 
 to be true which is absurd. 
 
 If this be really an absurdity. Liberty must 
 be given up. And if the appearance of 
 absurdity be owing to false colouring, I think 
 every argument this author has used, when 
 weighed in the balance of reason, will be 
 found light. 
 
 I would, therefore, think it a prudent 
 saving of time and labour, that contro\ ertists 
 on both sides should lay aside every other 
 weapon, till the force of this be fairly tried. 
 Mr Crombie triumphs in it almost m every 
 page ; and I think Dr Priestley urged it as 
 an apology for neglecting your essay, tliut 
 you pretended to demonstrate an absurdity. 
 It must, indeed, be granted, that even 
 the Deity cannot give a power to man, 
 which involves an absurdity. But if this 
 absurdity vanish, when seen in a just light, 
 then it will be time to examine the fact, 
 whether such a power is given to man or not. 
 
 Is a volition, undetermined by motives, 
 an uncaused eftect, and therefore an ab- 
 surdity and a contradiction ? 
 
 I grant that an uncaused effect is a con- 
 tradiction in terms ; for an eflect is some- 
 thing effected, and what is effected implies 
 an efficient, as an action implies an agent. 
 To say an effect must have a cause, is 
 really an identical proposition, which carries 
 no information but of the meaning of a word. 
 To say that an event — that is, a thing which 
 began to exist — must have a cause, is not an 
 identical proposition, and might have been 
 as easily said. I know I no] reason why 
 Mr Croiiibi(! shoidd stick by tliis impro- 
 priety, after it was censured in Dr Priestley,
 
 88 
 
 CORRESPONDENCE OF DR REID. 
 
 but that impropriety in the use of terms 
 is an expedient either to cover an absurdity 
 where it really is, or to make that appear 
 absurd which is not so m reality. 
 
 I grant, then, that an effect uncaused is 
 a contradiction, and that an event uncaused 
 is an absurdity. Tlie question that remains 
 is whether a volition, undetermined by mo- 
 tives, is an event uncaused. This I deny. 
 The cause of the volition is the man that 
 willed it. This Mr Crombie grants in 
 several places of his Essay — that the man is 
 the efficient cause of all his volitions. Is it 
 not strange, then, that, almost in every page, 
 he should affirm that a volition, undeter- 
 mined by motives, is an effect uncaused ? 
 Is an efficient cause no cause ? or are two 
 causes necessary to every event ?* Motives, 
 he thinks, are not the efficient but the physi- 
 cal cause of volitions, as gravity is of the 
 descent of a stone. Then, fair dealing 
 Mould have made him qualify the absurdity, 
 and, say that it is absurd that a volition 
 should be without a physical cause ; but to 
 have pleaded the absurdity thus qualified, 
 would have been a manifest pefitio principii. 
 
 I can see nothing in a physical cause but 
 a constant conjunction with the effect. Mr 
 Crombie calls it a necessary connection ; 
 but this no man sees in physical causes ; 
 and, if every event must have a physical 
 cause, then every event must have been 
 repeated in conjunction with its cause from 
 eternity, for it could have no constant con- 
 junction when first produced. 
 
 The most shocking consequences of the 
 system of necessity are avowed by this au- 
 thor without shame. Moral evil is nothing 
 but as it tends to produce natural evil. A 
 man truely enlightened, ought to have no 
 remorse for the blackest crimes. I think 
 he might have added that the villain has 
 reason to glory in his crimes, as he suffers 
 for them without his fault, and for the com- 
 mon good. Among the arts of this author, 
 the following are often put in practice : — 
 1. To supply the defect of argument by 
 abuse. 2. What he thinks a consequence 
 of the system of Liberty he imputes to his 
 adversaries as their opinion, though they 
 deny it. 3. What is urged as a conse- 
 quence of Necessity, he considers as imputing 
 an opinion to those who hold Necessity, and 
 thinks it answer that they hold no such 
 opinion. 4. What is said to invalidate an 
 argument for Necessity, he considers as an 
 
 • This is no removal of the difficulty. Is the man 
 determined to volition, and to a certain kind of voli- 
 tion, or is he not ? If the former, necessitation is 
 not avoided; if the latter, the admitted absurdity 
 emerges. Tne schemes of Liberty and of Nece-sity are 
 contradictory ol each other: they consequently ex- 
 clude any intermediate theory ; and one or other 
 must be true. Yet the possibility of neither can be 
 conceived ; for each equally involves what is inioni- 
 prehensible, if not what is absurd. But of this again, 
 — H. 
 
 argument against Necessity ; and thinks it 
 sufficient to shew that it does not answer a 
 purpose for which it never was intended, as 
 if what is a sufficient answer to an argument 
 for Necessity must be a conclusive argument 
 against Necessity. I believe, however, he 
 may claim the merit of adding the word 
 Libertarian to the English language, as 
 Priestley added that of Necessarian. — 
 Yours, 
 
 Tho. Reid.» 
 
 XXI. 
 
 [ The folloiving Letter to Dr Gregory is 
 quoted by Mr Stewart in his '' Disserta- 
 tion on the Progress of Metaphysical and 
 Moral Science.^' The dale is not given ; 
 and the original is not noiv extant among 
 the letters of Reid in the hands of Dr 
 Gregory's family. — H. ] 
 
 The merit of what you are pleased to call 
 my philosophy, lies, I think, chiefly, in hav- 
 ing called in question the common theory 
 of ideas, or images of things in the mind, 
 being the only objects of thought ; a theory 
 founded on natural prejudices, and so uni- 
 versally received as to be interwoven with 
 the structure of the language. Yet, were I 
 to give you a detail of what led me to call 
 in question this theory, after I had long held 
 it as self-evident and unquestionable, you 
 would think, as I do, that there was much 
 of chance in the matter. The discovery 
 was the birth of time, not of genius ; and 
 Berkeley and Hume did more to bring it to 
 light than the man that hit upon it. I 
 think there is hardly anything that can be 
 called mine in the philosophy of the mind, 
 which does not follow with ease from the 
 detection of this prejudice. I must, there- 
 fore, beg of you most earnestly to make no 
 contrast in my favour to the disparagement 
 of my predecessors in the same pursuits. I 
 can truly say of them, and shall always 
 avow, what you are pleased to say of me, 
 that, but for the assistance I have received 
 from their writings, I never could have 
 wrote or thought what I have done. 
 
 • Besides the preceding papers on the question of 
 Liherty and Necessity, there are extant, Remarks 
 at considerable length by Reid, on three sets of Objec. 
 tions made by a distinguished natural philosopher to 
 Dr Gregory's Essav, in the years 1786, 1*89, and 
 1790. Ihese Kcra'arks, though of much interest, 
 have been omitted : for they could not adequately be 
 understood apart from tlie relative Objections ; and 
 these it was deemed improper to publish posthu- 
 mously, after their author had expressly refused to 
 allow them to be printed during his life. — There are 
 also omitted, as of minor importance, two other 
 papers on the same question ; the one containing, 
 " Remarks on the Objections to Dr Gregory's hssay," 
 which were printed in the appendix to that Essay; 
 the other," Remarks" on apamphlel entitled " Ulus. 
 t rations of Liberty and Necessity, in Answer to Di 
 Gregory," published in 1795.— H,
 
 LETTERS TO THE REV. A. ALISON & PROFESSOR ROBISON. 89 
 
 D.— LETTER TO THE KEY. ARCHIBALD ALISON. 
 
 The following letter was addressed, by Dr Reid, to the Rev. Archibald Alison, 
 (LL.B., Prebendary of Sarum, &c.,) on receiving a copy of his " Essays on the Nature 
 and Principles of Taste" — a work of great ingenuity and elegance, and the first systematic 
 attempt to explain the emotions of sublimity and beauty on the principles of association. 
 It was originally published in 1790. It is, perhaps, needless to remind the reader that 
 Mr Alison was brother-in-law of Dr Gregory — H. 
 
 ON THE PHILOSOPHY OF TASTE. 
 
 Dear Sir, — I received your very oblig- 
 ing letter of Jan. 10, with two copies of your 
 book, about the middle of last week. I ex- 
 pected a meeting of Faculty, to which I might 
 present the book, and return you the thanks 
 of the society along with my own ; but we 
 have had no meeting since I received it. 
 In the meantime, I have read it with avidity 
 and with much pleasure ; and cannot longer 
 forbear to return you my cordial thanks for 
 this mark of your regard, and for the hand- 
 some compliment you make me in the book. 
 
 I think your principles are just, and that 
 you have sufficiently justified them by a 
 great variety of illustrations, of which many 
 appear new to me, and important in them- 
 selves, as well as pertinent to the purpose 
 for which they are adduced. 
 
 That your doctrine concerning the sub- 
 lime and beautiful in objects of sense coin- 
 cides, in a great degree, with that of the 
 Platonic school, and with Shaftesbury and 
 Akenside among the moderns, I think may 
 justly be said. They believed intellec- 
 tual beauties to be the highest order, com- 
 pared with which the terrestrial hardly de- 
 serve the name. They taught beauty and 
 good to be one and the same thing. But 
 both Plato and those two, his admirers, 
 handle the subject cf beauty rather with 
 the enthusiasm of poets or lovers, than with 
 the cool temper of philosophers. And it is 
 difficult to determine what allowance is to 
 he made, in what they have said, for the 
 hyperbolical language of enthusiasm. 
 
 The other two you mention, Dr Hutclic- 
 
 son and ]Mr Spence, though both admirers 
 of Plato, do not appear to me either to have 
 perceived this doctrine in him, or to have 
 discovered it themselves. The first places 
 beauty in uniformity and variety, which, 
 when they are perceived, immediately affect 
 that internal sense which he calls the sense 
 of beauty. The other makes colour, form, 
 expression, and grace to be the four ingre- 
 dients of beauty in the female part of our 
 species, without being aware that the beauty 
 of colour, form, and grace is nothing but 
 expression, as well as what he calls by that 
 name. 
 
 On these grounds, I am proud to think 
 that I first, in clear and explicit terms, and 
 in the cool blood of a philosopher, main- 
 tained that all the beauty and sublimity of 
 objects of sense is derived from the expres- 
 sion they exhibit of things intellectual, which 
 alone have original beauty. But in this I 
 may deceive myself, and cannot claim to be 
 held an impartial judge. 
 
 Though I don't expect to live to see the 
 second part of your work, I have no hesi- 
 tation in advising you to prosecute it ; being 
 persuaded that criticism is reducible to prin- 
 ciples of philosophy, which may be more 
 fully unfolded than they have been, and 
 which will always be found friendly to the 
 best interests of mankind, as well as to 
 manly and rational entertainment. 
 
 Mrs Reid desires to present her best re- 
 spects to Mrs Alison, to which I beg you 
 to add mine, and to believe me to be your 
 much obliged and faithful servant, 
 
 Tho. Reie. 
 
 Glasgow Collrqe, 
 3d Feb. 1790. 
 
 E.— LETTER TO PROFESSOR ROBISON. 
 
 There has been given above, (p. €>?,,) a letter by Dr Reid, in 170-1, recording a 
 remarkable conversation between Sir Isaac Newton and Professor James Gregory, 
 relative to Sir Issiac's descent from the family of Newton of Newton, in the county 
 of East Lothian. Some years thereafter, Mr Barron, a relation of Sir Isaac, seems 
 to have instituted in(|niripH in regard to the Scottish genealogy of the philosopher; in con-
 
 90 
 
 CORRESPONDENCE OF DR REID. 
 
 sequence of which, the late Professor Robison of Edinburgh, aware, pi-obably, of the 
 letter to Dr Gregory, was induced to apply to Dr Reid for a more particular accounV 
 of the conversation in question. The following is Reid's answer, as published in Sir 
 David Brewster's " Life of Sir Isaac Newton." — H. 
 
 Dear Sir, — I am very glad to learn, by 
 yours of April 4, that a Mr Barron, a near 
 relation of Sir Isaac Newton, is anxious to 
 inquire into the descent of that great man, 
 as the family cannot trace it farther, with 
 any certainty, than his grandfather. I there- 
 fore, as you desire, send you a precise ac- 
 count of all I know ; and am glad to have 
 this opportunity, before I die, of putting 
 this information in hands that will make the 
 proper use of it, if it shall be found of any 
 use. 
 
 Several years before I left Aberdeen, 
 (which I didm 1764,) Mr Douglas of Fecliel, 
 the father of Sylvester Douglas, now a bar- 
 rister at London, told me, that, having been 
 lately at Edinburgh, he was often in com- 
 pany of Mr Hepburn of Keith, a gentleman 
 with whom I had some acquaintance, by his 
 lodging a night at my house at NewMachar, 
 when he was in the rebel army m 1745. 
 That Mr Hepburn told him, that he had 
 heard Mr James Gregory, Professor of 
 Mathematics, Edinburgh, say, that, being 
 one day in familiar conversation with Sir 
 Isaac Newton at London, Sh- Isaac said — 
 " Gregory, I believe you don't know that 
 I am a Scotchman." — " Pray, how is that ?'' 
 said Gregory. Sir Isaac said, he was in- 
 formed that his grandfather (or great-grand- 
 father) was a gentleman of East (or West) 
 Lothian ; that he went to London with 
 King James I. at his accession to the crown 
 of England ; and that he attended the court, 
 in expectation, as many others did, until 
 he spent his fortune, by which means his 
 family was reduced to low circumstances. 
 At the time this was told me, Mr Gregory 
 was dead, otherwise I should have had his 
 own testimony ; for he was my mother's 
 brother. I likewise thought at that time, 
 that it had been certainly known that Sir 
 Isaac had been descended from an old 
 English family, as I think is said in his 
 eloi/e before the Academy of Sciences at 
 Paris; and therefore I never mentioned 
 what I had heard for many years, believing 
 that there must be some mistake in it. 
 
 Some years after I came to Glasgow, 
 I mentioned, (I believe for the first time,) 
 what I had heard to have been said by Mr 
 Hepburn, to Mr Cross, late sheriff of this 
 county, whom you will remember. Mr 
 Cross was moved by this account, and im- 
 mediately said — " I know Mr Hepburn very 
 well, and I know he was intimate with Mr 
 Gregory. I shall write him this same night, 
 to know whether he heard Mr Gregory say 
 so or not." After some reflection, he added 
 
 — " I know that Mr Keith, the ambassador, 
 was also an intimate acquaintance of Mr 
 Gregory, and, as he is at present in Edin- 
 burgh, I shall likewise write to him this 
 night." 
 
 The next time I waited on Mr Cross, 
 he told me that he had wrote both to Mr 
 Hepburn and Mr Keith, and had an 
 answer from both ; and that both of then: 
 testified that they had several times heard 
 Mr James Gregory say, that Sir Isaa-c New- 
 ton told hira what is above expressed, but 
 that neither they nor Mr Gregory, as far 
 as they knew, ever made any farther inquiry 
 into the matter. This appeared very strange 
 both to Mr Cross and me ; and he said he 
 would reproach them for their indifference, 
 and would make inquiry as soon as he was 
 able. 
 
 He lived but a short time after this ; and, 
 in the last conversation I had with him 
 upon the subject, he said, that all he had 
 yet learned was, that there was a Sir John 
 Newton of Newton in one of the counties of 
 Lothian, (but I have forgot which,) some 
 of whose children were yet alive ; that they 
 reported that their father, Sir John, had a 
 letter from Sir Isaac Newton, desiring to 
 know the state of his family ; what children 
 he had, particularly what sons ; and in what 
 way they were. The old knight never re- 
 turned an answer to this letter, thinking, 
 probably, that Sir Isaac was some upstart, 
 who wanted to claim a relation to his wor- 
 shipful house. This omission the children 
 regretted, conceiving that Sir Isaac might 
 have had a view of doing something for their 
 benefit. 
 
 Alter this, I mentioned occasionally in 
 conversation what I knew, hoping that these 
 facts might lead to some more certain dis- 
 covery ; but I found more coldness about 
 the matter than I thought it deserved. I 
 wrote an account of it to Dr Gregory, your 
 colleague, that he might impart it to any 
 member of the Antiquarian Society who he 
 judged might have had the curiosity to trace 
 the matter farther. 
 
 In the year 1787? my colleague, Mr 
 Patrick Wilson, Professor of Astronomy, 
 having been in London, told me, on his 
 return, that he had met accidentally with a 
 James Hutton, Esq. of Pimlico, Westmin- 
 ster, a near relation of Sir Isaac Newton, 
 to whom he mentioned what he had heard 
 from me with respect to Sir Isaac's descent, 
 and that I wished much to know something 
 decisive on the subject. Mr Hutton said, 
 if I pleased to write to him, he would give
 
 CORRESPONDENCE OF DR REID. 
 
 91 
 
 me all the information he could give. I 
 wrote him, accordingly, and had a very 
 polite answer, dated at Bath, 25th Decem- 
 ber 1787, which is now before me. He 
 says, " I shall be glad, when I return to 
 London, if I can find, in some old notes of 
 my mother, any thing that may fix the cer- 
 tainty of Sir Isaac's descent. If he spoke 
 so to Mr James Gregory, it is most cer- 
 tain he spoke truth. But Sir Isaac's 
 grandfather, not his great-grandfather, 
 must be the person who came from Scot- 
 land with King James I. If I find any 
 thing to the purpose, I will take care it 
 shall reach you." 
 
 This is all I know of the matter ; and 
 for the facts above mentioned, I pledge 
 my veracity. I am much obliged to you, 
 
 dear Sii for the kind expressions of your 
 affection and esteem, which, I assure you, 
 are mutual on my part ; and I sincerely 
 sympathise with you on your afflicting" 
 state of health, which makes you consider 
 yourself as out of the world, and despair 
 of seeing me any more. 
 
 I have been long out of the world by 
 deafness and extreme old age. I hope, 
 however, if we should not meet again in 
 this world, that we shall meet and renew 
 our acquaintance in another. In the 
 meantime, I am, with great esteem, dear 
 Sir, yours affectionately, 
 
 Tho. RErn. 
 
 Glasgow College, 
 12th April 1792. 
 
 F.— LETTER TO DAVID HUME. 
 
 The following is in answer to the letter of Hume, given by Mr Stewart in his Ac- 
 count of Reid, {supra, p. 7, sq.) It is recently published, from the Hume papers, 
 by Mr Burton, in his very able life of the philosopher ; and, though out of chrono- 
 logical order, (by the reprinting of a leaf,) it is here inserted. — H. 
 
 IN REFERENCE TO UIS OWN INQUIRY, 
 PRIOR TO ITS PUBLICATION. 
 
 King's College, [_Aberdeen,^ 
 ISth March 1763. 
 
 Sir, — On Monday last, Mr John Far- 
 quhar brought me your letter of February 
 25th, enclosed in one from Dr Blair. I 
 thought myself very happy in having 
 the means of obtaining at second hand, 
 through the friendship of Dr Blair, your 
 opinion of my performance : and you have 
 been pleased to communicate it directly 
 in so polite and friendly a manner, as 
 merits great acknowledgments on my 
 part. Your keeping a watchful eye over 
 my style, with a view to be of use to 
 me, is an instance of candour and gene- 
 rosity to an antagonist, which would affect 
 me very sensibly, although I had no per- 
 sonal concern in it, and I shall always be 
 proud to show so amiable an example. 
 Your judgment of the style, indeed, gives 
 me great consolation, as I was very diffi- 
 dent of myself in regard to English, and 
 have been indebted to Drs Campbell and 
 Gerard for many corrections of that 
 kind. 
 
 In attempting to throw some new light 
 
 • Kant m.'iki^s a similar acknowlcdgmnnt. "By 
 Ilumo," ho says, " I waH firHt KtartliMl out of my 
 doffmatic: slumber." Thus Humo (aw flsowhiTO 
 Kl.-itcfl) ia author, in a sort, of all our HuliKriiucnt 
 philoHOphy. Koroutof Ur'id ami Kant, mediately 
 or imme'liately, all our Buhsc'iuent philosoi>liy if 
 
 upon those abstruse subjects, I wish to 
 preserve the due mean betwixt confidence 
 and despair. But whether I have any 
 success in this attempt or not, I shall 
 always avow myself your disciple in me- 
 taphysics. I have learned more from 
 your writings in this kind, than from all 
 others put together. Your system appears 
 to me not only coherent in all its parts, 
 but Ukewise justly deduced from princi- 
 ples commonly received among philoso- 
 phers ; principles which I never thought 
 of calling in question, until the conclu- 
 sions you draw from them in the Treatise 
 of Human Nature made me suspect them. 
 If these principles are solid, your system 
 must stand ; and whether they are or not, 
 can better be judged after you have 
 brought to light the whole system that 
 grows out of them, than when the greater 
 part of it was wrapped up in clouds and 
 darkness. I agree with you, therefore, 
 that if this system shall ever be de- 
 molished, you have a just claim to a great 
 share of the praise, both because you have 
 made it a distinct and determined mark 
 to be aimed at, and have furnished pro- 
 per artillery for the purpose.* 
 
 <!Volv(5d; and tlie dortrlncB of Kant and Itcid are 
 both avowedly rocoila from tho annihilating scop- 
 ticiHm of Hume— both altemijts to find for jihllo- 
 HOphy deeper foundationw than those whieh ho 
 had so thoroughly 8ubvcrt<'d.— H.
 
 92 
 
 CORRESPONDENCE OF DR REID. 
 
 When you have seen the whole of my 
 performance, I shall take it as a very 
 great favour to have your opinion upon 
 it, from which I make no doubt of re- 
 ceiving light, whether I receive correc- 
 tion or no. Your friendly adversaries 
 Drs Campbell and Gerard, as well as Dr 
 Gregory, return their compliments to you 
 respectfully. A little philosophical so- 
 ciety here, of which all the three are 
 members, is much indebted to you for its 
 "utertainment. Your company would. 
 
 although we are all good Christians, be 
 more acceptable than that of St Athana- 
 sius ; and since we cannot have you upon 
 the bench, you are brought oftener than 
 any other man to the bar, accused and 
 defended with great zeal, but without 
 bitterness. If you write no more in 
 morals, politics, or metaphysics, I am 
 afraid we shall be at a loss for subjects. 
 I am, respectfully, Sir, your most obliged, 
 humble servant, 
 
 Thomas Reid. 
 
 The following should have been inserted in the correspondence with Karnes. 
 Kames's objection to Dr Adam Smith's theory of Sympathy as the sole foundation of 
 our moral judgments, which appeared in the third edition of the " Essays on 
 Morality," were, previously to publication, communicated to Dr Reid, who thus 
 expresses his opinion on the subject : — 
 
 " I have always thought Dr S 's system of sympathy wrong. It is indeed only 
 
 a refinement of the selfish system ; and I think your arguments against it are solid. 
 But you have smitten with a friendly hand, which does not break the head ; and 
 your compliment to the author I highly approve of." — From Letter of 30th October 
 1778. 
 
 In this judgment of Smith, Reid and Kant are at one. The latter condemns the 
 Ethic of Sympathy as a Eudsemonism, or rather Hedonism. — H. 
 
 In Button's Mathematical Dictionary, 1795, in the article, David Gregory, 
 there are given, " Some farther particulars of the families of Gregory and Ander- 
 son, communicated by Dr Thomas Reid," &c., probably written in the year of 
 publication, or the preceding. As these notices contain nothing of any moment which 
 does not appear in the foregoing correspondence, it has been deemed unnecessary 
 to reprint them H.
 
 AN 
 
 INQUIRY 
 
 INTO 
 
 THE HUMAN MIND, 
 
 ON THE PHINCIPLES OF 
 
 COMMON SENSE. 
 
 By T H O M A S R E I D, D. D , 
 
 PROFESSOR OF MORAL PHILOSOPHY IN THE UNIVERSITY OF GLASGOW. 
 "The inspiration of the Almighty giveth them understanding."— Jon.
 
 (t^ This Inquiry was first published in 17C4, when Dr Reid was Professor of Philo- 
 sophy, in King's College, Aberdeen. Three subsequent editions were printed during the 
 author's lifetime — in 1765, 17G9, and 1785. The text of the present impression is 
 taken from the last authentic edition— the fourth, or that of 1785, which professes to be 
 " corrected;" collated, however, with the first, and any variations of importance 
 noticed H.
 
 DEDICATION. 
 
 TO 
 
 THE RIGHT HONOURABLE 
 
 JAMES, EARL OF FINDLATEE AND SEAFIELD,* 
 
 CHANCELLOR OF THE UNIVERSITY OF OLD ABERDEEN. 
 
 My Lord, — Though I apprehend that 
 there are things new and of some import- 
 ance, m the following Inquiry, it is not 
 without timidity that I have consented to 
 the puLhcation of it. The subject has been 
 canvassed by men of very great penetration 
 and genius : for who does not acknowledge 
 Des Cartes, Malebranche, Locke, Berkeley, 
 and Hume, to be such ? A view of the 
 human understanding, sodifferent from that 
 which they have exhibited, will, no doubt, 
 be condemned by many, without examin- 
 ation, as proceeding from temerity and 
 vanity. 
 
 But I hope the candid and discerning Few, 
 who are capable of attending to the opera- 
 tions of their own minds, will weigh delibe- 
 rately what is here advanced, before they 
 pass sentence upon it. To such I appeal, 
 as the only competent judges. If they dis- 
 approve, I am probably in the wrong, and 
 shall be ready to change my opinion upon 
 conviction. If they approve, the Many will 
 at last yield to their authority, as they always 
 do. 
 
 However contrary my notions are to those 
 of the writers I have mentioned, their spe- 
 culations have been of great use to me, and 
 seem even to point out the road which I 
 have taken : and your Lordship knows, that 
 tlie merit of useful discoveries is sometimes 
 not more justly due to those that have hit 
 upon them, than to others that have ripened 
 them, and brought them to the birth. 
 
 I acknowledge, my Lord, that I never 
 thought of calling in ([iicstion the principles 
 commonly received with regard to the hu- 
 man understanding, until the " Treatise of 
 Human Nature" was puljlished in the year 
 1 TM). The ingenious author of that treatise 
 upon the principles of Locke — who was no 
 
 » In the first edition. •• Jamcg Lord l)e»kfoord" — 
 >ii» father being ttill alive.— II. 
 
 sceptic — hath built a system of scepticism, 
 which leaves no ground to believe any one 
 thing rather than its contrary. His reason- 
 ing appeared to me to be just ; there was, 
 therefore, a necessity to call in question the 
 principles upon which it was founded, or to 
 admit the conclusion-* 
 
 But can any ingenuous mind admit this 
 sceptical system without reluctance ? I 
 truly could not, my Lord ; for I am per- 
 suaded, that absolute scepticism is not more 
 destructive of the faith of a Christian than 
 of the science of a philosopher, and of the 
 prudence of a man of common understand- 
 ing. I am persuaded, that the unjust live 
 by faith-\' as well as the jusl ; that, if alf 
 belief could be laid aside, piety, patriotism, 
 friendship, parental affection, and private 
 virtue, would appear as ridiculous as knight- 
 errantry ; and that the pursuits of pleasure, 
 of ambition, and of avarice, must be 
 grounded upon belief, as well as those that 
 are honourable or virtuous. 
 
 The day-labourer toils at his work, in the 
 belief that he shall receive his wages at 
 night ; and, if he had not this belief, ho 
 would not toil. We may venture to say, 
 that even the author of this sceptical 
 system wrote it in the belief that it 
 
 • " I'his doctrine of Ideas," (says Dr'Keid.in a sub. 
 sequent work,) " I once believed so firmly, as to cm- 
 brace tlie whole of Berkeley's system in eonscqueiice 
 of it ; till, finding other consequences to follow from 
 it, which g:ive nie more uneasiness than the want of 
 a material world, it came into my mind, more than 
 forty years ago, to put the question, What evidence 
 have I f(jr this doctrine, that all the ohjeets of my 
 knowledge are ideas in my own mind ?" — lissays on 
 the Intcllictunl I'otpcrs, i:ss. II. cli. X p. KiJ. 
 
 In like manner, Kant informs us, that it was by 
 Hume's sceptical inferences, in regard to the causal 
 nexus, that he also " was first rousi-d from his dog. 
 matic slumber." See the " Prolegomena," p 13.— 
 II. 
 
 t .See Note A at the end of the volume, in illuslra. 
 fion of tlie principle, that the root of Knowledge is 
 Belief.— H.
 
 96 
 
 OF THE HUMAN iMIND. 
 
 should be read and regarded. I hope he 
 wrote it in the behef also that it would be 
 useful to mankind ; and, perhaps, it may 
 prove so at last. For I conceive the scep- 
 tical writers to be a set of men whose busi- 
 ness it is to pick holes in the fabric of 
 knowledge wherever it is weak and faulty ; 
 and, when these places are properly repaired, 
 the whole building becomes more firm and 
 solid than it was formerly. 
 
 For my own satisfaction, I entered into 
 a serious examination of the principles upon 
 which this sceptical system is built ; and 
 was not a little surprised to find, that it 
 leans with its whole weight upon a hypo- 
 thesis, which is ancient indeed, and hath 
 been very generally received by philoso- 
 phers, but of which I could find no solid 
 proof. The hypothesis I mean, is, That 
 nothing is perceived but what is in the 
 mind which perceives it : That we do not 
 really perceive things that are external, but 
 only certain images and pictures of them 
 imprinted upon the mind, which are called 
 impressions and ideas. 
 
 If this be true, supposing cei-tain im- 
 pressions and ideas to exist in my mind, • I 
 cannot, from their existence, infer the exist- 
 ence of anything else : my impressions and 
 ideas are the only existences of which I can 
 have any knowledge or conception ; and 
 they are such fleeting and transitory beings, 
 that they can have no existence at all, any 
 longer tlian I am conscious of them. So 
 that, upon this hypothesis, the whole uni- 
 verse about me, bodies and spirits, sun, 
 moon, stars, and earth, friends and rela 
 tions, all things without exception, which 
 I imagined to have a permanent existence, 
 whether I thought of them or not, vanish 
 at once ; 
 
 " And, like the baseless fabric of a vision. 
 Leave not a track behind." 
 
 I thought it unreasonable, my Lord, upon 
 the authority of philosophers, to admit a 
 hypothesis which, in my opinion, overturns 
 all philosophy, all religion and virtue, and 
 all common sense-j- — and, finding that all the 
 systems concerning the human understand- 
 ing which I was acquainted with, were built 
 upon this hypothesis, I resolved to inquire 
 into this subject anew, without regard to any 
 hypothesis. 
 
 What I now humbly present to your 
 Lordship, is the fruit of this inquiry, so far 
 only as it regards the five senses : in which 
 I claim no other merit than that of having 
 
 » In first edition, " to exist presently in my 
 mind." 1 may here, once for all, notice that pre. 
 saitly, (in its original and proper sense, and as it is 
 frequently employed by Reid,) for now or at present, 
 has WHXcd oVisdlete in English. For above a century 
 ani a half, it is only lo be found in good English 
 writers in the secondary meaning of in a little while 
 —without tielay. — H. 
 
 + See Note A at the end of the volume, in defence 
 and illustration of the term Common Sense. — H. 
 
 given great attention to the operations of my 
 own mind, and of having expressed, with all 
 the perspicuity I was able, what I conceive 
 every man, who gives the same attention, 
 will feel and perceive. The productions of 
 imagination require a genius which soars 
 above the common rank ; but the treasures 
 of knowledge are commonly buried deep, 
 and may be reached by those drudges who 
 can dig with labour and patience, though 
 they have not wings to fly. The experi- 
 ments that were to be made in this investi- 
 gation suited me, as they required no other 
 expense but that of time and attention, 
 which I could bestow. The leisure of an 
 academical life, disengaged from the pur- 
 suits of interest and ambition ; the duty of 
 my profession, whif^h obliged me to give 
 prelections on these subjects to the youth ; 
 and an early inclination to speculations of 
 this kind, have enabled me, as I flatter my- 
 self, to give a more minute attention to the 
 subject of this inquu-y, than has been given 
 before. 
 
 My thoughts upon this subject were, a 
 good many years ago, put together in an- 
 other form, for the use of my pupils, and 
 afterwards were submitted to the judgment 
 of a private philosophical society,* of which 
 I have the honour to be a member. A 
 great part of this Inquiry was honoured 
 even by your Lordship's perusal. And 
 the encouragement which you, my Lord, 
 and others, whose friendship is my boast, 
 and whose judgment I reverence, were 
 pleased to give me, counterbalance my timi- 
 dity and diffidence, and determined me to 
 ofler it to the public. 
 
 If it appears to your Lordship to justify 
 the common sense and reason of mankind, 
 against the sceptical subtilties which, in 
 this age, have endeavoured to put them out 
 of countenance — if it appears to throw any 
 new light upon one of the noblest parts of 
 the divine workmanship — your Lordship's 
 respect for the arts and sciences, and your 
 attention to everything which tends to the 
 improvement of them, as well as to every- 
 thing else that contributes to the felicity of 
 your country, leave me no room to doubt 
 of your favourable acceptance of this essay, 
 as the fruit of my industry in a profession-h 
 wherein I wasj accountable to your Lord- 
 ship ; and as a testimony of the great esteem 
 and respect wherewith I have the honour 
 to be. 
 
 My Lord, 
 Your Lordship's most obliged 
 
 And most devoted Servant, 
 
 Tho. Reid.§ 
 
 » See above, p 4i,b. — H. 
 
 t Keid, here and elsewhere, uses profession for chair 
 ox professorship. — H. 
 
 t " Am" — first edition — H. 
 
 ^ In first edition this dedication is dated— " King'* 
 College, Nov. 9, 1763."— H.
 
 AN 
 
 INQUIRY INTO THE HUMAN MIND. 
 
 CHAPTER I. 
 
 INTRODUCTION. 
 
 Section I, 
 
 THE IMPORTANCE OK THE SUBJECT, AND THE 
 MEANS OF PROSECUTING IT. 
 
 The fabric of the human mind is curious 
 and wonderful, as well as that of the human 
 body. The faculties of the one are with no 
 less wisdom adapted to their several ends 
 than the organs of the other. Nay, it is 
 reasonable to think, that, as the mind is a 
 nobler work and of a higher order than the 
 body, even more of the wisdom arid skill o. 
 tlie divine Architect hath been employed in 
 its structure. It is,* therefore, a subject 
 highly worthy of inquiry on its own account, 
 but still more worthy on account of the 
 extensive influence which the knowledge of 
 it hath over every other branch of science. 
 In the arts and sciences which have least 
 connection with the mind, its faculties are 
 the engines which we must employ ; and 
 the better we understand their nature and 
 use, their defects and disorders, the more 
 skilfully we shall apply them, and with the 
 greater success. Iiut in the noljlcst arts, 
 the mind is also the subject* upon which 
 we operate. The painter, the poet, the actor, 
 the orator, the moralist, and the statesman, 
 attempt to operate upon the mind in differ- 
 ent ways, and for different ends ; and they 
 succeed according as they touch properly 
 the fitriuKS of the human frame. Nor can 
 
 • In philosophical language, it were to bo wished 
 that the word subject should be reserved lor the sub- 
 ject of inhiai n — the tiiatrria in qua \ and the term 
 vbjfct ixtiu>ivcly ajiplied to the subject of operation 
 — the materia circn (/7ia?ii. It this be not dijnc, the 
 Krand distinction of subjective and olijrctive, in phi- 
 losophy, i>. confounded. But if the employment of 
 Suiject tor Object is to be deprecated, the em|)loy. 
 ment of (Jlijcct for purjiose or tinal cause, (iti tli • 
 French and Ijinlish lannuatjcs,) is to be absolutely 
 roridcmned, as a recent and irrational contusion ot 
 notions winch -.hould be careful ly dintinguiihed. — H. 
 
 their several arts ever stand on a solid found- 
 ation, or rise to the dignity of science, until 
 they are built on the principles of the human 
 constitution. 
 
 Wise men now agree, or ought to arrree, 
 m this, that there is but one way to the 
 knowledge of nature's works — the way of 
 observation and experiment. By our con- 
 stitution, we have a strong propensity to 
 trace particular facts and observations to 
 general rules, and to apply such general 
 rules to account for other effects, or to direct 
 us in the production of them. This proce- 
 dure of the understanding is familiar to 
 every human creature in the common affairs 
 of li-'e, and it is the only one by which any 
 real discovery in philosophy can be made. 
 
 The man who first discovered that cold 
 freezes water, and that heat turns it into 
 vapour, proceeded on the same general prin. 
 ciples, and in the same method by which 
 Newton discovered the law of gravitation 
 and the properties of light. His regulce 
 o/iUosophundi are maxims of common sense, 
 and are practised every day in common 
 life ; and he who philosophizes by other 
 rules, either concerning the material sys- 
 tem or concerning the mind, mistakes his 
 aim. 
 
 Conjectures and theories* are the crea- 
 tures of men, and will always be found very 
 unlike the creatures of God. If we would 
 know the works of God, we must consult 
 themselves with attention and humility, 
 witl'.out daring to add anything of ours 
 to what they declare. A just interpretation 
 of nature is the only sound and orthodox 
 philosophy : whatever we add of our own, 
 is apocryphal, and of no authority. 
 
 All our curious theories of the formation 
 of the earth, of the generation of animals, 
 of the origin of natural and moral evil, so 
 far as tliey go beyond a just induction from 
 
 • Reid uses the terms, Theory, Hypothesis, and 
 CV;ryVe/KM', as ((invert dile, and always in an unfavour. 
 able acceptation Herein there is a double inaccu- 
 racy. But of this again.— H. 
 
 II
 
 98 
 
 OF THE HUiMAN MIND. 
 
 facts, are vanity and folly, no less than the 
 Vortices of Des Cartes,* or the Archaeus 
 of Paracelsus. Perhaps the philosophy of 
 the mind hath been no less adulterated by 
 theories, than that of the material system. 
 The theory of Ideas is indeed very ancient, 
 and hath been very universally received ; 
 but, as neither of tliese titles can give it 
 authenticity, they ought not to screen it from 
 a free and candid examination ; especially in 
 this age, when it hath produced a system of 
 scepticism that seems to triumph over all 
 science, and even over the dictates of com- 
 mon sense. 
 
 All that we know of the body, is owing 
 to anatomical dissection and observation, 
 and it must be by an anatomy of the mind 
 that we can discover its powers and prin- 
 ciples. 
 
 Section II. 
 
 THE IMPEDIMENTS TO OUR KNOWLEDGE OF 
 THE MIND. 
 
 But it must be acknowledged, that this 
 kind of anatomy is much more difficult than 
 the other ; and, therefore, it needs not 
 seem strange that mankind have made 
 less progress in it. To attend accurately 
 to the operations of our minds, and make 
 them an object of thought, is no easy mat- 
 ter even to the contemplative, and to the 
 bulk of mankind is next to impossible. 
 
 An anatomist who hath happy opportu- 
 nities, may have access to examine with 
 his own eyes, and with equal accuracy, 
 bodies of all different ages, sex^s, and 
 conditions ; so that what is defective, ob- 
 scure, or preternatural in one, may be 
 discerned clearly and in its most perfect 
 state in another. But the anatomist of the 
 mind cannot have the same advantage. It 
 is his own mind only that he can examine 
 with any degree of accuracy and distinct- 
 ness. This is the only subject he can look 
 into. He may, from outward signs, collect 
 the operations of other minds ; but these 
 signs are for the most part ambiguous, and 
 must be interpreted by what he perceives 
 within himself. 
 
 So that, if a philosopher could delineate 
 to us, distinctly and methodically, all the 
 operations of the thinking principle within 
 him, which no man was ever able to do, 
 this would be only the anatomy of one par- 
 ticular subject ; which would be both defi- 
 cient and erroneous, if applied to human 
 nature in general. For a little reflection 
 
 » No one deemed more lightly of liis hypotheses 
 than Des Cartes himself He called them " philosoph. 
 ical romances ;" and thus anticipated Father Daniel, 
 who again anticipated Voltaire, in the saying — Ihe 
 Philotophy uf Des Cartes is the Homancc of Nature. 
 
 may satisfy us, that the difference of minds 
 is greater than that of any other beings 
 which we consider as of the same species. 
 
 Of the various powers and faculties we 
 possess, there are some which nature seems 
 both to have planted and reared, so as to 
 have left nothing to human industry. Such 
 arc the powers which we have in common 
 with the brutes, and which are necessary 
 to the preservation of the individual, or the 
 continuance of the kind. There are other 
 powers, of which nature hath only planted 
 the seeds in our minds, but hath left the 
 rearing of them to human culture. It is by 
 the proper culture of these that we are cap- 
 able of all those improvements in intellec- 
 tuals, in taste, and in morals, which exalt 
 and dignify human nature ; while, on the 
 other hand, the neglect or perversion of 
 them makes its degeneracy and corruption. 
 
 The two-legged animal that eats of na- 
 ture's dainties, what his taste or appetite 
 craves, and satisfies his thirst at the crystal 
 fountain, who pi-opagates his kind as occa- 
 sion and lust prompt, repels injuries, and 
 takes alternate labour and. repose, is, like a 
 tree in the forest, purely of nature's growth. 
 But this same savage hath within him the 
 seeds of the logician, the man of taste and 
 breeding, the orator, the statesman, the man 
 of virtue, and the saint ; which seeds, though 
 planted in his mind by nature, yet, through 
 want of culture and exercise, must lie for 
 ever buried, and be hardly perceivable by 
 himself or by others. 
 
 The lowest degree of social life will bring 
 to light some ot those principles which lay 
 hid in the savage state ; and, according to 
 his training, and company, and manner of 
 life, some of them, either by their native 
 vigour, or by the force of culture, will thrive 
 and grow up to great perfection, others will 
 be strangely perverted from their natural 
 form, and others checked, or perhaps quite 
 eradicated. 
 
 This makes human nature so various and 
 multiform in the individuals that partake of 
 it, that, in point of morals and intellectual 
 endowments, it fills up all that gap which 
 we conceive to be between brutes and devils 
 below, and the celestial orders above ; and 
 such a prodigious diversity of minds must 
 make it extremely difficult to discover the 
 common principles of the species. 
 
 The language of philosophers, with re- 
 gard to the original faculties of the mind, 
 is so adapted to the prevailing system, tlsat 
 it cannot fit any other ; like a coat that fits 
 the man for whom it was made, and shews 
 him to advantage, which yet will sit very 
 awkward upon one of a different make, 
 although perhaps as handsome and as well 
 proportioned. It is hardly possible to make 
 any innovation in our philosophy concern- 
 ing the mind and its operations, without
 
 INTRODLXTION'. 
 
 
 using new words and phrases, or giving a 
 different meaning to those that are received 
 — a liberty which, even when necessary, 
 creates prejudice and misconstruction, and 
 whicli must wait the sanction of time to 
 authorize it ; for innovations in hmguage, 
 like those in rehgion and government, are 
 always suspected and disliked by tlie many, 
 till use hath made them famihar, and pre- 
 scription hath given them a title. 
 
 If the original perceptions and notions of 
 the mind were to make their appearance 
 single and unmixed, as we first received 
 them from the hand of nature, one accus- 
 tomed to reflection would have less difficulty 
 in tracing them ; but before we are capa- 
 ble of reflection, they are so mixed, com- 
 pounded, and decompounded, by habits, 
 associations, and abstractions, tiiat it is 
 hard to know what they weie originally. 
 The mind may, in this respect, be compared 
 to an apothecary or a chemist, whose mate- 
 rials indeed are furnished by nature ; but, 
 for the purposes of his art, he mixes, com- 
 pounds, dissolves, evaporates, and sublimes 
 tliem, till they put on a quite different 
 appearance ; so that it is very difficult to 
 know what they were at first, and much 
 more to bring them back to their original 
 and natural form. And this work of the 
 mind is not carried on by delil:)erate acts of 
 mature reason, which we might recollect, 
 but l)y means of instincts, habits, associa- 
 tions, and other principles, which operate 
 before we come to the use of reason ; s(j 
 that it is extremely difficult for the mind 
 to return upon its own footsteps, and trace 
 back those operations which liave employed 
 it since it first began to think and to net. 
 
 Could we obtain a distinct and full his- 
 tory of all that hath past in the mind of a 
 child, from the beginning of life and sensa- 
 tion, till it grows up to the use of reason — 
 how its infant faculties began to work, and 
 liow they brought forth and ripened all the 
 various notions, opinions, and sentiments 
 which we find in ourselves when we come 
 to be cajiable of reflection — tliis would be 
 a treasure of natural liistory, which would 
 probably give more light into the human 
 faculties, than all the systems of philoso- 
 phers about them since the beginning of 
 the world. But it is in vain to wish lor 
 what nature has not put within the reach 
 of our power. Reflection, the only instru- 
 ment by whicli we can discern tlie powers 
 of the mind, comes too late to observe the 
 progress of nature, in raising them from 
 their infancy to perfection. 
 
 It must therffore require great caution, 
 and great aiiplication of mind, for a mati 
 tliat is grown up in all the prejudices of 
 education, fashion, and ]iliiloso[)liy, to 
 unravel his notions and opiuions, till lie 
 find out the simple and original principles 
 
 of his constitution, of which no account 
 can be given but the will of our jNlaker. 
 This may be truly called an auii/t/.sis of the 
 human faculties ; and, till this is performed, 
 it is in vain we expect any just .■'ps/em of 
 the mmd — that is, an enumeration of the 
 original powers and laws of our constitution, 
 and an explication from tliem of the various 
 phcenomena of human nature. 
 
 Success in an inquiry of this kind, it is 
 not in human power to command ; but, per- 
 haps, it is possible, l)y caution and humility, 
 to avoid error and delusion. The labyrinth 
 may be too intricate, and the thread too 
 fine, to be traced through all its windings ; 
 but, if we stop whore wo can trace it no 
 farther, and secure the ground we have 
 gained, there is no harm done ; a quicker 
 eye may in time trace it farther. 
 
 It is genius, and not the want of it, that 
 adulterates philosophy, and fills it with 
 error and false theory. A ci-eative imagi- 
 nation disdains the mean offices of digging 
 for a foundation, of removing rubbish, and 
 carrying materials ; leaving tljese servile 
 employments to the drudges in science, it 
 plans a design, and raises a fabric. Inven- 
 tion supplies materials where they are 
 wanting, and fancy adds colouring and 
 every befitting ornament. The work 
 pleases tlie eye, and wants nothing hut 
 solidity and a good foundation. It seems 
 even to vie with the works of nature, till 
 some succeeding architect blows it into 
 rubbish, and builds as goodly a fabric of 
 his own in its place. Happily for the pre- 
 sent age, 4he castle-builders employ them- 
 selves more in romance than in philosophy. 
 That is undoubtedly their province, and 
 in those regions the offspring of fancy is 
 legitimate, but in philosophy it is all spu- 
 rious. * 
 
 Section III. 
 
 THE PRESENT STATE OF THIS PART OF PHILO- 
 SOPHY — OF DES CARTES, WALKBRANCHB, 
 AND LOrKE. 
 
 That our jthilosophy concerning the mind 
 and its faculties is but in a very low state, 
 may be reasonably conjectured even by 
 tliose who never have narrowly examined 
 it. Are there any principles, with regard 
 to the mind, settled with that perspicuity 
 aiid evidence which a! tends the principles 
 of mechanics, astronomy, and o])tics ? 
 These are really sciences built upon laws of 
 nature which universally obtain. What is 
 
 • The fiame doctrine of the iiicomi)atit)ility of crea- 
 •ive iinaKiialini) and philoiophiciil talent, is held I'v 
 Hume and Kant I'hcre is required, hnvvcvcr, for 
 the metaplly^l(•laIl, not leiiii iinaginalion than lor tlie 
 poet, thoiiph of a did'cTent kind ; il may, in fact, lie 
 doubted whether Homer or Aiistotle pnssoued ihi< 
 faculty in (jroater vigour. — H. 
 
 n 2
 
 100 
 
 OF THE HUMAN MIND. 
 
 discovered in them is no longer matter of 
 dispute : future ages may add to it ; but, 
 till the course of nature be changed, what is 
 already established can never be overturned. 
 But when we turn our attention inward, and 
 consider the phtenomena of human thoughts, 
 opinions, aud perceptions, and endeavour to 
 trace them to the general laws and the first 
 principles of our constitution, we are imme- 
 diately involved in darkness and perplexity ; 
 and, if common sense, or the principles of 
 education, happen not to be stubborn, it is 
 odds but we end in absolute scepticism. 
 
 Des Cartes, finding nothing established in 
 this part of philosophy, in ortler to lay the 
 foundation of it deep, resolved not to believe 
 his own existence till he should be able to 
 give a good reason for it. He was, per- 
 haps, the first that took up such a resolu- 
 tion ; but, if he could indeed have effected 
 his purpose, and really become diffident of 
 his existence, his case would have been 
 deplorable, and without any remedy from 
 reason or philosophy. A man that dis- 
 beUeves his own existence, is surely as unfit 
 to be reasoned with as a man that believes 
 he is made of glass. There may be dis- 
 orders in the human frame that may pro- 
 duce such extravagancies, but they will never 
 be cured by reasoning. Des Cartes, in- 
 deed, would make us believe that he got out 
 of this delirium by this logical argument, 
 Cofjilo, ergo sum ; but it is evident he was 
 in his senses all the time, and never seri- 
 ously doubted of his existence ; for he takes 
 it for granted in this argument, and proves 
 nothing at all. I am thinking, says he — 
 therefore, I am. And is it not as good rea- 
 soning to say, I am sleeping — therefore, I 
 am ? or, I am doing nothing — therefore, I 
 am ? If a body moves, it must exist, no 
 doubt ; but, if it is at rest, it must exist 
 likewise.* 
 
 Perhaps Des Cartes meant not to assume 
 ais owu existence in this enthymeme, but 
 the existence of thought ; aud to infer from 
 ,hat the existence of a mind, or subject of 
 'bought. But why did he not prove the 
 existence of his thought ? Consciousness, 
 it may be said, vouches that. But who 
 is voucher for consciousness ? Can any 
 man prove that his consciousness may not 
 deceive him ? No man can ; nor can we 
 give a better reason for trusting to it, than 
 that every man, while his mind is sound, is 
 determinetl, by the constitution of his na- 
 ture, to give implicit belief to it, and to 
 laugh at or pity the man who doubts its 
 testimony. And is not every man, in his 
 wits, as much determined to take his exist- 
 ence upon trust as his consciousness ? 
 
 * The nature of the Cartesian Doubt and its solu- 
 tion is here misapprehended — how, will be shewn in 
 a note upon the eighth chapter of the second " liss.iy 
 jn ihe In'.ellcctual Powers." — H. 
 
 The other proposition assumed hi this 
 argument, Tliat thought cannot be without 
 a mind or subject, is liable to the same 
 objection : not that it wants evidence, but 
 that its evidence is no clearer, nor more 
 immediate, than that of the proposition to 
 be proved by it. And, taking all these pro 
 positions together — I think ; I am con- 
 scious ; Everything that thinks, exists ; I 
 exist — would not every sober man form the 
 same opinion of the man who seriously 
 doubted any one of tliein ? And if he was 
 his friend, would he not hope for his cure 
 from physic and good regimen, rather than 
 from metaphysic and logic ? 
 
 But supposing it proved, that my thought 
 and my consciousness must have a subject, 
 and consequently that I exist, how do I 
 know that all that train and succession of 
 thoughts which I remember belong to one 
 subject, and tliat the I ' of this moment is 
 the very individual I of yesterday and of 
 times past ? 
 
 Des Cartes did not think proper to start 
 this doubt ; but Locke has done it ; and, in 
 order to resolve it, gravely determines that 
 personal identity consists in consciousness — 
 that is, if you are conscious that you did 
 such a thing a twelvemonth ago, this con- 
 sciousness makes you to be the very person 
 that did it. Now, consciousness of what is 
 past can signify nothing else but the re- 
 membrance that I did it ; so that Locke's 
 principle must be, That identity consists in 
 remembrance ; and, consequently, a man 
 must lose his personal identity with regard 
 to everytliing he forgets. 
 
 Nor are tliese the only instances whereby 
 our philosophy concerning the mind appears 
 to be very fruitful in creating doubts, but 
 very unhappy in resolving them. 
 
 Des Cartes, Malebranche, and Locke, 
 have all employed their genius and skill to 
 prove the existence of a material world : 
 and with very bad success. Poor untaught 
 mortals believe undoubtedly that there is a 
 sun, moon, and stars ; an earth, which we 
 inhabit ; country, friends, and relations, 
 which we enjoy ; land, houses, and move- 
 ables, which we possess. But philosophers, 
 pitying the credulity of the vulgar, resolve 
 to have no faith but what is founded upon 
 reason. -f- They ajjply to j)hilosophy to fur- 
 
 * In English, we cannot say the I, and the Nct-I 
 so happily as the Fr^ nch le Mot, and le Non.Mot, or 
 even the Germans rtas 7f A, and das Nicht.Ich. 'the 
 ambiguity arising from the identity of sound between 
 the I audthe eye, would of itself preclude the ordinary 
 employment ol the former / he Ego and the Non- 
 Ego are the best terms we can u-e ; and, as the ex. 
 pressions are scientific, it ispirhapsno loss that their 
 technical p'-ecision is guarded by their non-vernacul- 
 arity — H. 
 
 + Reason is here employed, by Reid, not as a 
 synonyine for Common Sense, {\,ov;, locus princi. 
 pioruni,) and as he himself more correctly employs 
 it in his later works, but as equivalent to Reason- 
 ing, ( Siavoix, discursu* mentalis.) See Note A. — H.
 
 INTRODUCTION. 
 
 101 
 
 nish them with reasons for the belief of 
 those things which all mankind have be- 
 lieved, without being able to give any rea- 
 son for it. And surely one would expect, 
 that, in matters of such importance, tlie 
 proof would not be difficult : but it is the 
 most difficult thhig in the world. For these 
 three great men, with the best good will, 
 have not been able, from all the treasures 
 of philosophy, to draw one argument that 
 is fit to convince a man that can reason, of 
 the existence of anj' one thmg without him. 
 Admired Philosophy ! daughter of light ! 
 parent of wisdom and knowledge ! if thou 
 art she, surely thou hast not yet arisen 
 upon tlie human mind, nor blessed us with 
 more of thy rays than are sufficient to shed 
 a darkness visible upon the human facul- 
 ties, and to disturb that repose and security 
 which happier mortals enjoy, who never 
 approached thine altar, nor felt thine in- 
 fluence ! But if, indeed, thou hast not 
 power to dispel those clouds and phantoms 
 which thou hast discovered or created, with- 
 draw this penurious and malignant ray ; I 
 despise Philosophy, and renounce its guid- 
 ance — let my soul dwell with Common 
 Sense.* 
 
 Section IV. 
 
 APOLOGY FOR THOSE PHILOSOPHERS. 
 
 But, insteadof despising the dawn of light, 
 we ought rather to hope for its increase : 
 instead of blaming the philosophers I have 
 mentioned for the defects and blemishes of 
 their system, we ought rather to honour 
 their memories, as the first discoverers of a 
 region in philosophy formerly unknown ; 
 and, however lame and imperfect the sys- 
 tem may be, they have opened the way to 
 future discoveries, and are justly entitled to 
 a great share in tlie merit of them. They 
 have removed an infinite deal of dust and 
 rubbish, collected in the ages of scholastic 
 sophistry, which had obstructed the way. 
 They have put us in the right road — that 
 of experience and accurate reflection. They 
 have taught us to avoid the snares of am- 
 biguous and ill-defined words, and have 
 spoken and thought upon this subject wiih 
 a distinctness and perspicuity formerly un- 
 known. They have made many openings 
 that may lead to the discovery of trutlis 
 which tlioy did not reach, or to the detec- 
 tion of errors in which they were involun- 
 tarily entangled. 
 
 It may be observed, that the defects and 
 blemishes in the received philosopliy con- 
 cerning the mind, which have most exposed 
 
 • Mr Stewart very justly ccn«iire« tlie vagueness 
 and ainiaBuity of thij (lauagp. Klem. vol, ii., rh. i , 
 \ \ p. 02, flvo wlitioiii,,— H. 
 
 it to the contempt and ridicule of sensible 
 men, have chiefly been owing to this — that 
 the votaries of this Philosophy, from a na- 
 tural prejudice in her favour, have endea- 
 voured to extend her jurisdiction beyond its 
 just limits, and to call to her bar the dictates 
 of Common Sense. But these decline this 
 jurisdiction ; they disdain the trial of rea- 
 soning, and disown its authority ; they 
 neither claim its aid, nor dread its attacks. 
 In this unequal contest betwixt Common 
 Sense and Philosophy, the latter will always 
 come oft" both with dishonour and loss ; not 
 can she ever thrive till this rivalship is 
 dropt, these encroachments given up, and 
 a cordial friendship restored : for, iu reality, 
 Common Sense holds nothing of Philoso- 
 phy, nor needs her aid. But, on the other 
 hand, Philosophy (if I may be permitted to 
 change the metaphor) has no other root but 
 the principles of Common Sense ; it grows 
 out of them, and draws its nourishment from 
 them. Severed from this root, its honours 
 wither, its sap is dried up, it dies and rots. 
 The philosophers of the last age, whom I 
 have mentioned, did not attend to the pre- 
 serving this union and subordination so 
 carefully as the honour and interest of phi- 
 losophy required : but those of the present 
 have waged open war with Common Sense, 
 and hope to make a complete conquest of it 
 by the subtilties of Philosophy — an attempt 
 no less audacious and vain than that of the 
 giants to dethrone almighty Jove. 
 
 Section V. 
 
 OF BISHOP BERKELEY — THE " TREATISE OK 
 HUMAN nature" — AND OF SCEPTICISM. 
 
 The present age,I apprehend, has not pro- 
 duced two more acute or more practised in 
 this part of philosophy, than the Bishop of 
 (Jloyne, and the author of the " Treatise of 
 Human Nature." The first was no friend 
 to scepticism, but had that warm concern 
 for religious and moral principles which be- 
 came his order : yet the result of his inquiry 
 was a serious conviction that there is no 
 such thing as a material world — nothing in 
 nature but spirits and ideas ; and that the 
 belief of material substances, and of abstract 
 ideas, are the chief causes of all our errors 
 in philosophy, and of all infidelity and heresy 
 in religion. Mis arguments are founded 
 upon the principles which were formerly 
 laid down by J)i's Cartes, Malel)ranche, and 
 Locke, and which have been very generally 
 received. 
 
 And the opinion of the ablest judges 
 seems to be, that they neither have been, 
 nor can bo confuted ; and that he hath 
 proved by unanswerable arguments wliat no 
 mnii ill bis senses crin bpli<vo.
 
 102 
 
 OF THE HUMAN MIND. 
 
 The second proceeds upon tlie same prin- 
 ciples, but carries them to their full length ; 
 and, as the Bishop undid the whole material 
 world, this author, upon the same grounds, 
 undoes the world of spirits, and leaves no- 
 thing in nature but ideas and impressions, 
 without any subject on which they may be 
 impressed. 
 
 it seems to be a peculiar strain of humour 
 in this author, to set out in his introduction 
 by promising, with a grave face, no less than 
 a complete system of the sciences, upon a 
 foundation entirely new — to wit, that of hu- 
 man nature — when the intention of the 
 whole work is to shew, that there is neither 
 human nature nor science in the world. It 
 may perhaps be unreasonable to complain 
 of this conduct in an author who neither 
 believes his own existence nor that of his 
 reader ; and therefore could not mean to 
 disappoint him, or to laugh at his credulity. 
 Yet I cannot imagine that the author of the 
 " Treatise of Human Nature" is so scep- 
 tical as to p'ead this apology. He believed, 
 against his princijiles, that he should be 
 read, and that he should retain his personal 
 identity, till he reaped the honour and repu- 
 tation justly due to his metaphysical acumen. 
 Indeed, he ingeniously acknowledges, that 
 it was only in solitude and retirement that 
 he could yield any assent to his own philo- 
 sophy ; society, like day-light, dispelled the 
 darkness and fogs of scepticism, and made 
 him yield to the dominion of common sense. 
 Nor did I ever hear hiiu charged with doing 
 anything, even in solitude, that argued 
 such a degree of scepticism as his principles 
 maintain. Sui-ely if his friends apprehended 
 this, they would have the charity never to 
 leave him alone. 
 
 Pyrrho the Elean, the father of this phi- 
 losophy, seems to have carried it to greater 
 perfection than any of his successors : for, 
 if we may believe Antigonus the Carystian, 
 quoted by Diogenes Laertius, his life cor- 
 responded to his doctrine. And, therefore, 
 if a cart run against him, or a dog attacked 
 him, or if he came upon a precipice, he 
 would not stir a foot to avoid the danger, 
 giving no credit to his senses. But his at- 
 tendants, who, happily for him, were not so 
 great sceptics, took care to keep him out of 
 harm's way ; so that he lived till he was 
 ninety years of age. Nor is it to be doulited 
 but this author's friends would have been 
 equally careful to keep him from harm, if 
 ever his principles had taken too strong a 
 hold of him. 
 
 It is probable the " Treatise of Human 
 Nature"' was not written in company ; yet 
 it contains manifest indications that the 
 author every now and then relapsed into 
 the faith of the vulgar, and could hardly, 
 for half a dozen pages, keep up the seai>- 
 tical character. 
 
 In like manner, the great Pyrrho him- 
 self forgot his principles on some occasions ; 
 and is said once to have been in such a 
 passion with his cook, who probably had not 
 roasted his dinner to his mind, that with 
 the spit in his hand, and the meat upon it, 
 he pursued him even into the market- 
 place.* 
 
 It isabold philosophy that rejects, without 
 ceremony, principles which irresistibly go- 
 vern the belief and the conduct of all man- 
 kind in the common concerns of life ; and 
 to which the philosopher himself must yield, 
 after he imagines he hath confuted them. 
 Such principles are older, and of more au- 
 thority, than Philosophy : she rests upon 
 them as her basis, not they upon her. If 
 she could overturn them, she must be buried 
 in their ruins ; but all the engines of philo- 
 sophical subtilty are too weak for this pur- 
 pose ; and the attempt is no less ridiculous 
 than if a mechanic should contrive an axift 
 in ppritrochio to remove the earth out of 
 its place ; or if a mathematician should pre- 
 tend to demonstrate that things equal to 
 the same thing are not equal to one an- 
 other. 
 
 Zeno+ endeavoured to demonstrate the 
 impossibility of motion ;:{: Hobbes, that there 
 was no difference between right and wrons ; 
 and this author, that no credit is to be given 
 to our senses, to our memory, or even to 
 demonstration. Such philosophy is^ justly 
 ridiculous, even to those who cannot detect 
 the fallacy of it. It can have no other tend- 
 ency, than to shew the acuteness of the 
 sophist, at the expense of disgracing reason 
 and human nature, and making mankind 
 Yahoos. 
 
 Section VI. 
 
 OF THE " TREATISE OF HUMAN NATURE." 
 
 There are other prejudices against this 
 system of human nature, which, even upon 
 a general view, may make one diffident of 
 it. 
 
 Des Cartes, Hobbes, and this author, 
 have each of them given us a system of 
 human nature ; an undertaking too vast for 
 any one man, how great soever his genius 
 and abilities may be. There must surely 
 be reason to apprehend, that many parts of 
 human nature never came under their 
 observation ; and that others have been 
 stretched and distorted, to fill up blanks, 
 and complete the system. Christopher 
 
 » I aertius L. ix. Spg 68— H. 
 
 + Zpno of Elea There arc fifteen Zenos known 
 in the histnry df Philosophy ; of these, Laertius sig. 
 nalizes eight.— H. 
 
 % I he fallacy of Zcno's exposition of the contra. 
 diet on» involved in our notion of motion, has not 
 yet been detected. — H.
 
 INTRODUCTION. 
 
 103 
 
 Columbus, or Sebastian Cabot, might almost 
 as reasonably have undertaken to give us a 
 complete map of America. 
 
 There is a certain character and style in 
 Nature's works, which is never attained 
 in the most perfect imitation of them. 
 This seems to be wanting in the systems of 
 human nature I have mentioned, and par- 
 ticularly in the last. One may see a pup- 
 pet make variety of motions and gesticula- 
 tions, which strike much at first view ; but 
 when it is accurately observed, and taken 
 to pieces, our admiration ceases : we com- 
 prehend the whole art of the maker. How 
 unlike is it to that which it represents ! 
 What a ])oor piece of work compared with 
 the body of a man, whose structure the 
 more we know, the more wonders we dis- 
 cover in it, and the more sensible we are of 
 our ignorance ! Is the mechanism of the 
 mind so easily comprehended, when that of 
 the body is so difficult ? Yet, by this sys- 
 tem, three laws of association, joined to a 
 few original feelings, explain the whole 
 mechanism (>f sense, imagination, memory, 
 belief, and of all the actions and passions of 
 the mind. Is this the man that Nature 
 made ? I suspect it is not so easy to look 
 behind the scenes in Nature's work. This 
 is a puppet, surely, contrived by too bold an 
 apprentice of Nature, to mimic her work. 
 It shews tolerably by candle light ; but, 
 brought into clear day, and taken to pieces, 
 it will appear to be a man made with mor- 
 tar and a trowel. The more we know of 
 other parts of nature, the more we like and 
 approve them. The little I know of the 
 planetary system ; of the earth which we 
 inhabit ; of minerals, vegetables, and ani- 
 mals ; of my own body ; and of the laws 
 which obtain in these parts of nature — opens 
 to my mind grand and beautiful scenes, and 
 contributes equally to my happiness and 
 power. But, when I look within, and con- 
 sider the mind itself, which makes nu; 
 capable of all these jirospccts and enjoy- 
 ments— if it is, indeed, what the " Treatise 
 of Human Nature" makes it — I find IJiave 
 been only in an enchanted castle, imposed 
 upon by spectres and apparitions. 1 blush 
 inwardly to think how 1 liavebeen deluded; 
 1 am a>hamed of my frame, and can hardly 
 forbear expostulating with my destiny. Is 
 this thy pastime, O Nature', to put such 
 tricks upon a silly creature, and then to take 
 off the mask, and shew him how lie hath 
 been befooled ? If this is the philosophy of 
 human nature, my soul enter thou not into 
 her secrets ! It is surely the forbidden 
 tree of knowledge ; I no sooner taste; of it, 
 than I perceive myself naked, and stri])! of 
 all things — yea, even of my very self. I 
 see myself, and the whole frame of nature, 
 shrink into fleeting ideas, which, like Ejii- 
 curus's atoms, dance about in <MiptineK8. 
 
 Scclion VI f. 
 
 THE SYSTEM OF ALL THESE AUTHORS IS THE 
 SAME, AND LEADS TO SCEPTICISM. 
 
 But what if these profound disquisitions 
 into the first pi-inciples of human nature, 
 do naturally and necessarily plunge a man 
 into this abyss of scepticism ? May we not 
 reasonably judge so from what hath hap- 
 pened ? Des Cartes no sooner began to 
 dia: in this mine, than scepticism was ready 
 to break in upon him. He did what he 
 could to shut it out. Malebranche and 
 Locke, who dug deeper, found tlie difHculty 
 of keeping out this enemy still to increase ; 
 but they laboured honestly in the design. 
 Then Berkeley, who carried on the work, 
 despairing of securing all, bethought him- 
 self of an expedient: — By giving up the \j 
 material world, which he thought might 
 be spared without loss, and even with ad- 
 vantage, he hoped, by an impregnable par- 
 tition, to secure the world of s])irits. But, 
 alas ! the " Treatise of Human Nature" 
 wantonly sapped the foundation of this 
 partition, and drowned all in one universal 
 deluge. 
 
 These facts, which are undeniable, do, 
 indeed, give reason to apprehend that Des 
 Cartes' system of the human understand- 
 ing, which I shall beg leave to call the ideal 
 !<ysl('m, and which, with some improvements 
 made by later writers, is now generally 
 received, hath some original defect ; that 
 this scepticism is inlaid in it, and reared 
 along with it ; and, therefore, that we must 
 lay it open to the foundation, and examine 
 the materials, before we can expect to raise 
 any solid and useful fabric of knowledge on 
 this subject. 
 
 Seclion VIII. 
 
 WE OUGHT NOT TO DESrAIU OF A JiETTEH. 
 
 But is this to be despaired of, because 
 Des Cartes and his followers have failed ? 
 By no means. This pusillanimity would bo 
 injurious to ourselves and injurious to truth. 
 Useful discoveries are sometimes indeed 
 the efiect of superior genius, but more fre- 
 quently they are the birth of time and of 
 accidents. A travellerof good judgment may 
 mistake his way, and be unawares led into 
 a wrong track ; and, while the road is fair 
 bei'ore him, ho may go on without suspicion 
 and be followed by others; but, when it 
 ends in a coal-i)it, it reciuii-es no great judg- 
 ment to know that he hath gime wrong, 
 nor perhaps to find out what misled him. 
 
 In the nK'antinie, the unprosperous state 
 of this part of philosoiihy hath iiroduced an
 
 104 
 
 OF THE HUMAN MIND. 
 
 cflFect, somewhat discouraging indeed to 
 any attempt of this nature, but an effect 
 which might be expected, and wliich time 
 only and better success can remedy. Sen- 
 sible men, who never will be sceptics in 
 matters of conmion life, are apt to treat 
 with sovereign contempt everything that 
 hath been said, or is to be said, upon this 
 subject. It is metaphysic, say they : who 
 minds it ? Let scholastic sophisters e.i- 
 tangle themselves in their own cobwebs ; I 
 
 Vam resolved to take my own existence, and 
 the existence of other things, upon trust ; 
 and to believe that snow is cold, and 
 honey sweet, whatever they may say to 
 the contrary. He must either be a fool, 
 or want to make a fool of me, that would 
 reason me out of my reason and senses. 
 
 I confess I know not what a sceptic can 
 answer to this, nor by what good argument 
 he can plead even for a hearing ; for either 
 his reasoning is sophistry, and so deserves 
 contempt ; or there is no truth in human 
 faculties — and then why should we reason ? 
 
 If, therefore, a man findhiraself intangled 
 in these metaphysical toils, and can find no 
 other way to escape, let him bravely cut 
 the knot which he cannot loose, curse me- 
 taphysic, and dissuade every man from 
 meddling with it ; for, if I have been led 
 into bogs and quagmires by following an 
 i/jnis fatnus, what can I do better than to 
 t-' warn others to beware of it ? If philoso- 
 phy contradicts herself, befools her votaries, 
 and deprives them of every object worthy 
 to be pursued or enjoyed, let her be sent 
 back to the infernal regions from which she 
 must have had her original. 
 
 But is it absolutely certain that this fair 
 lady is of the party ? Is it not possible 
 she may have been misrepresented ? Have 
 not men of genius in former ages often 
 made their own dreams to pass for her 
 oracles ? Ought she then to be condemned 
 without any further hearing ? This would 
 be unreasonable. I have found her in all 
 other matters an agreeable companion, a 
 faithful counsellor, a friend to common 
 sense, and to the happiness of mankind, 
 'i'his justly entitles her to my correspond- 
 ence and confidence, till I find infallible 
 proofs of her infidelity. 
 
 CHAPTER II. 
 
 OF SMELLING. 
 
 Section J. 
 
 THE ORDER OF PROCEEDING — OF THE 
 MEDIUM AND ORGAN OF SMELL. 
 
 It is so difficult to unravel the operations 
 of the human understanding, and to reduce 
 
 tlieni to their first principles, that we can- 
 not expect to succeed in the attempt, but 
 by beginning with the simplest, and pro- 
 ceeding by very cautious steps to the more 
 complex. The five external senses may, 
 for this reason, claim to be first considered 
 in an analysis of the human faculties. 
 And the same reason ought to determine 
 us to make a choice even among the senses, 
 and to give the precedence, not to the 
 noblest or most useful, but to the simplest, 
 and that whose objects are least in danger 
 of being mistaken for other things. 
 
 In this view, an analysis of our sensa- 
 tions may be carried on, perhaps with most 
 ease and distinctness, by talung them in 
 this order : Smelling, Tasting, Hearing, 
 Touch, and, last of all, Seeing. 
 
 Natural philosophy informs us, that all 
 animal and vegetable bodies, and probably 
 all or most other bodies, while exposed to 
 the air, are continually sending forth efflu- 
 via of vast subtilty, not only in their state 
 of life and growth, but in the states of fer- 
 mentation and putrefaction. These volatile 
 particles do probably repel each other, and 
 so scatter themselves in the air, until they 
 meet with other bodies to which they have 
 some chemical affinity, and with which they 
 unite, and form new concretes. All the 
 smell of plants, and of other bodies, is caused 
 by these volatile parts, and is smelled wher- 
 ever they are scattered in the air : and the 
 aeuteness of smell in some animals, shews 
 us, that these effluvia spread far, and must 
 be inconceivably subtile. 
 
 Whether, as some chemists conceive, 
 every species of bodies hath a spiritus rector, 
 a kind of soul, which causes the smell and 
 all the specific virtues of that body, and 
 which, being extremely volatile, flies about 
 in the air in quest of a proper receptacle, I 
 do not inquire. This, like most other 
 theories, is perhaps rather the product of 
 imagination than of just induction. But 
 that all bodies are smelled by means of 
 effluvia* which they emit, and which are 
 drawn into the nostrils along with the air, 
 there is no reason to doubt. So that there 
 is manifest appearance of design in placing 
 the organ of smell in the inside of that canal, 
 through which the air is continually passing 
 in inspiration and expiration. 
 
 Anatomy informs us, that the mnnbrana 
 piluifaria, and the olfactory nerves, which 
 are distributed to the villous parts of this 
 membrane, are the organs destined by the 
 
 * It is wrong to say that "a body is smelled by 
 mrans of effluvia" Nothing is smelt but the effluvia 
 themselves. 'Ihey constitute tlie total object of per- 
 ception in smell ; andin all Ihesensesthe only ol)ject 
 perceived, is that in immediate contact with tlie or- 
 gan. There is, in reality, no medium in any sense; 
 and, as Democritus long ago shrewdly observed, ali 
 the senses are only modifications of touch. — H.
 
 OF SMELLING. 
 
 105 
 
 wisdom ef nature to this sense ; so tliat 
 when a body emits no effluvia, or when they 
 do not enter into the nose, or when the 
 pituitary membrane or olfactory nerves are 
 rendered unfit to perform their office, it can- 
 not be smelled. 
 
 Yet, notwithstanding this, it is evident 
 that neither the organ of smell, nor the 
 medium, nor any motions we can conceive 
 excited in tlie membrane above mentioned, 
 or in the nerve or animal spirits, do in the 
 least resemble the sensation of smelling ; 
 nor could that sensation of itself ever have 
 led us to think of nerves, animal spirits, or 
 effluvia. 
 
 Section II. 
 
 THE SENSATION CONSIDERED ABSTRACTLY. 
 
 Having premised these things with re- 
 gard to the medium and organ of this sense, 
 let us now attend carefully to what the mind 
 is conscious of when we smell a rose or a 
 lily; and, since our language affords no 
 other name for this sensation, we shall call 
 it a i,mell or odour, carefully excluding from 
 the meaning of those names everything but 
 the sensation itself, at least till we have ex- 
 amined it. 
 
 Suppose a person who never had this 
 sense before, to receive it all at once, and 
 to smell a rose — can he perceive any simi- 
 litude or agreement between the smell and 
 the rose ? or indeed between it and any 
 other object whatsoever ? Certainly he can- 
 not. He finds himself affected in a new 
 way, he knows not why or from what cause. 
 Like a man that feels some pain or pleasure 
 formerly unknown to him, he is conscious 
 that he is not the cause of it himself; but 
 cannot, from the nature of the thing, deter- 
 mine whether it is caused by body or spirit, 
 by something near, or by something at a 
 distance. It has no similitude to anything 
 else, so as to admit of a comparison ; and, 
 therefore, he can conclude nothing from it, 
 unless, perhaps, that there must be some 
 unknown cause of it. 
 
 It is evidently ridiculous to ascribe to it 
 figure, colour, extension, or any other 
 quality of bodies. He cannot give it a place, 
 any more than he can give a place to mel- 
 ancholy or joy ; nor can he conceive it to 
 have any existence, but when it is smelled. 
 So that it appears to be a simple and original 
 affection or feeling of the mind, altogether 
 inexplicable and unaccountable. It is, in- 
 deed, impossible that it can be in any body : 
 it i« a sensation, and a sensation can only 
 be in a sentient thing. 
 
 The various odours have each their dif- 
 ferent degrees of strength or weakness. 
 Moat fif them are agreeable or disagree- 
 
 able ; and frequently those that are agree- 
 able when weak, are disagreeable when 
 stronger. When we compare different 
 smells together, we can perceive very few 
 resemblances or contrarieties, or, indeed, 
 relations of any kind between them. They 
 are all so simple in themselves, and so dif- 
 ferent from each other, that it is hardly 
 possible to divide them into genera and 
 species. Most of the names we give them 
 are particular ; as the smell of a rose, of a 
 jessamine, and the like. Yet there are 
 some general names — as sweet, stinking, 
 nnisty, putrid^ cadaverous, aromatic. Some 
 of them seem to refresh and animate the 
 mind, others to deaden and depress it. 
 
 Section II J. 
 
 SENSATION AND REMEMBRANCE, NATURAL 
 PRINCIPLES Of BELIEF. 
 
 So far we have considered this sensation 
 abstractly. Let us next compare it with 
 other things to which it bears some relation. 
 And first I shall compare this sensation 
 with the remembrance, and the imagination 
 of it. 
 
 I can think of the smell of a rose when I 
 do not smell it ; and it is possible that when 
 I think of it, there is neither rose nor smel\ 
 anywhere existing. But when I smell it, 
 I am necessarily determined to believe that 
 the sensation really exists. This is common 
 to all sensations, that, as they cannot exist 
 but in being perceived, so they cannot be 
 perceived but they must exist. I could as 
 easily doubt of my own existence, as of the 
 existence of my sensations. Even those 
 profound philosophers who have endeavoured 
 to disprove their own existence, have yet 
 left their sensations to stand upon their 
 own bottom, stript of a subject, rather than 
 call ill question the reality of their existence. 
 
 Here, then, a sensation, a smell for in- 
 stance, may be presented to the mind three 
 different ways : it may be smelled, it may 
 be remembered, it may be imagined or 
 thought of. In the first case, it is neces- 
 sarily accompanied with a belief of its pre- 
 sent existence ; in the second, it is neces- 
 sarily accompanied with a belief of its past 
 existence ; and in the last, it is not accom- 
 panied with lielief at all," but is what the 
 logicians call a simple apprchcnsii.H. 
 
 Why sensation should compel our belief 
 of the present existence of the thing, me- 
 mory a bchef of its pjist existence, and 
 
 • This is not strictly correct. The imagination 
 of an object is necessarily accdiiipatiicd with a belief 
 of the existence of the menial representation. Iteid 
 uses the term existence for ohjcctivc exisli.tir only, 
 and takes no account of the poH-ibilitv of a /.ufijcctivh 
 ciislincr. — H.
 
 106 
 
 OF THE HUMAN MIND, 
 
 imagination no belief at all, I believe no 
 philosopher can give a shadow of reason, 
 but that such is the nature of these opera- 
 tions : they are all simple and original, and 
 therefore inexplicable acts of the mind. 
 
 Suppose that once, and only once, I 
 smelled a tuberose in a certain room, where 
 it grew in a pot, and gave a very grateful 
 perfume. Next day I relate what I saw 
 and smelled. When I attend as carefully 
 as I can to what passes in my mind in this 
 case, it appears evident that the very thing 
 I saw yesterday, and the fragrance I smelled, 
 are now the immediate objects of my mind, 
 when I remember it. Further, I can 
 imagine this pot and flower transported to 
 the room where I now sit, and yielding the 
 same perfume. Here likewise it appears, 
 that the individual thing which I saw and 
 smelled, is the object of my imagination.* 
 
 Philosophers indeed tell me that the 
 immediate object of my memory and ima- 
 gination* in this case, is not the past sensa- 
 tion, but an idea of it, an image, phantasm, 
 or species,-)- of the odour I smelled : that 
 this idea now exists in my mind, or in my 
 Eensorium ; and the mind, contemplating 
 this present idea, finds it a representation 
 of what is past, or of what may exist ; and 
 accordingly calls it memory, or imagination. 
 This is the doctrine of the ideal philosophy ; 
 which we shall not now examine, that we 
 may not interrupt the thread of the present 
 investigation. Upon the strictest atten- 
 tion, memory appears to me to have things 
 that are past, and not present ideas, for its 
 object. We shall afterwards examine this 
 system of ideas, and endeavour to make it 
 appear, that no solid proof has ever been 
 advanced of the existence of ideas ; that 
 they are a mere fiction and hypothesis, con- 
 trived to solve the phtenomena of the hu- 
 man understanding ; that they do not at all 
 answer this end ; and that this hypothesis 
 of ideas or images of things in the mind, or 
 in the sensorium, is the parent of those 
 many paradoxes so shocking to common 
 sense, and of that scepticism which disgrace 
 our philosophy of the mind, and have 
 brought upon it the ridicule and contempt 
 of sensible men. 
 
 In the meantime, I beg leave to think, 
 with the vulgar, that, when I remember the 
 smell of the tuberose, that very sensation 
 which I had yesterday, and which has now 
 
 « For an exposition of Reid's error in ngard to 
 tY\e>hnmediate objec nfMemnryand Imagination, see 
 Kote B at the end of the volume — H. 
 
 f It will be oiseiveil, that Keid understands by 
 Ida, Imnife, I'hnnlnsm, Specie ,SfC, always a icr- 
 tium quid num rically different hoth from the Object 
 exist in tratiri from the Subject knowing. He had formed 
 no conreption of a doctrine in which a representative 
 o'ljtct is allowed, but only as a modification of the 
 mind itself. On the evil consequences iit this error, 
 both on his own philosophy and on his criticism of 
 other opinions, see Note C at the tnd of the volume. 
 
 no more any existence, is the immediate 
 object of my memory ; and when I imagine 
 it present, the sensation itself, and not any 
 idea of it,is the object of my imagination. But, 
 though the object of my sensation, memory, 
 and imagination, be in this case the same, 
 yet these acts or operations of the mind are 
 as different, and as easily distinguishable, 
 as smell, taste, and sound. I am conscious 
 of a difference in kind between sensation 
 and memory, and between both and imag- 
 ination. I find this also, that the sensation 
 compels my belief of the present existence 
 of the smell, and memory my belief of its 
 past existence. There is a smell, is the 
 immediate testimony of sense ; there was a 
 smell, is the immediate testimony of mem- 
 ory. If you ask me, why I believe that the 
 smell exists, I can give no other reason, 
 nor shall ever be able to give any other, 
 than that 1 smell it. If you ask, why I 
 believe that it existed yesterday, I can give 
 no other reason but that I remember it. 
 
 Sensation and memory, therefore, are 
 simple, original, and perfectly distinct opera- 
 tions of the mind, and both of them are 
 original principles of belief. Imagination 
 is distinct from both, but is no principle of 
 belief. Sensation implies the present exist- 
 ence of its object, memory its past existence, 
 but imagination views its object naked, and 
 v.'ithout any belief of its existence or non- 
 existence, and is therefore what the schools 
 call Simple Apprehension.* 
 
 Section I V. 
 
 JUDGMENT AND BELIEF IN SOME CASES PRE- 
 CEDE SIMPLE APPREHENSION. 
 
 But here, again, the ideal system comes 
 in our way : it teaches us that the first 
 operation of the mind about its ideas, is 
 simple apprehension— that is, the bare 
 conception of a thing without any belief 
 about it : and that, after we have got 
 simple apprehensions, by comparing them 
 together, we perceive agreements or dis- 
 agreements between them ; and that this 
 perception of the agreement or disagreement 
 of ideas, is all that we call belief, jurigment, 
 or knowledge. Now, this appears to me to 
 be all fiction, without any foundation in 
 nature ; for it is acknowledged by all, that 
 sensation must go before memory and im- 
 agination ; and hence it necessarily follows, 
 that apprehen.sion, acompanied with belief 
 and knowledge, must go before simple ap- 
 prehension, at least in the matters we are 
 now speaking of. So that here, instead of 
 
 ■ Simple Appi-ekersion, in the IdnRiiage of the 
 Schools, has no rcierence to any exclusion of belief. 
 It was merely given to the conceptio.i ot simple, in 
 contrast to the cognition of complex, terms. — H.
 
 OF SMELLING. 
 
 107 
 
 saying that the belief or knowledge is got 
 by putting together and comparing the 
 simpleapprehensions, we ought ratherto say 
 that the simple apprehension is performed 
 bv resolvinsr and analvsins: a natural and 
 original judgment. And it is with the 
 operations of the mind, in this case, as 
 with natural bodies, which are, indeed, 
 compounded of simple principles or ele- 
 ments. Nature does not exhibit these ele- 
 ments separate, to be compounded by us ; 
 she exhibits them mixed and compounded 
 in concrete bodies, and it is only by art and 
 chemical analysis that they can be separated. 
 
 Stdion V. 
 
 TWO THEORIES OF THE NATURE OF BELIEF 
 
 REFUTED CONCLUSIONS FROM WHAT 
 
 HATH BEEN SAID. 
 
 But what is this belief or knowledf;e 
 which accompanies sensation and memory ? 
 Every man knows what it is, but no man 
 can define it. Does any man pretend 
 to define sensation, or to define con- 
 sciousness ? It is happy, indeed, that 
 no man does. And if no philosopher had 
 endeavoured to define and explain belief, 
 some paradoxes in philosophy, more in- 
 credible than ever were brought forth by 
 the most abject superstition or the most 
 frantic enthusiasm, had never seen the light. 
 Of this kind surely is that modern discovery 
 of the ideal philosophy, that sensation, me- 
 mory, belief, and imagination, when they 
 have the same object, are only difierent 
 degrees of strength and vivacity in the 
 idea.* Suppose the idea to be that of a 
 future state after death : one man believes 
 it firmly — this means no more than that he 
 hath a strong and lively idea of it ; another 
 neither Lelievcs nor disbelieves — that is, he 
 has a weak and faint idea. Suppose, now, a 
 third [jerson believes firmly that there is no 
 such tiling, I am at a loss to know whether 
 his idea be faint or lively : if it is faint, 
 then there may be a firm belief where the 
 idea is faint ; if the idea is lively, then the 
 belief of a future state and the belief of no 
 future state must be one and the same. The 
 same arguments that are used to prove tliat 
 belief in)i)lies only a stronger idea of the 
 object tlian simple a]i))rehension, miglit as 
 well be used to prove that love implies only 
 a stronger idea of the object than indifi'er- 
 ence. And then what shall we say of 
 hatred, whicli mustnjion this liyjiothesis be 
 a degree of love, or a degree of iiidiflerenco ? 
 If it should Ik' said, that in love there is 
 fiomctliiiig more than an idea — to wit, an 
 affection of the mind — may it not be said 
 
 • Mr refers to niimc. — H. 
 
 with equal reason, that in belief there is 
 something more than an idea — to wit, an 
 assent or persuasion of the mind ? 
 
 But perhaps it may be thought as ridicu- 
 lous to argue against this strange opinion, 
 as to maintain it. Indeed, if a man should 
 maintain that a circle, a square, and a 
 triangle differ only in magnitude, and not 
 in figure, I believe he would find nobody 
 disposed either to believe him or to argue 
 against him ; and yet I do not think it less 
 shocking to common sense, to maintain that 
 sensation, memory, and imagination differ 
 only in degree, and not in kind. I know 
 it is said, that, in a delirium, or in dreaming, 
 men are apt to mistake one for the other. 
 But does it follow from this, that men who 
 are neither dreaming nor in a delirium 
 cannot distinguish them ? But how does 
 a man know that he is net in a delirium ? 
 I cannot tell : neither can I tell how a man 
 knows that he exists. But, if any man seri- 
 ously doubts whether he is in a delirium, I 
 think it highly probable tliat he is, and that 
 it is time to seek for a cure, which I am 
 persuaded he will not find in the whole 
 system of logic. 
 
 I mentioned before Locke's notion of 
 belief or knowledge ; he holds that it con- 
 sists in a perception of the agreement or 
 disagreement of ideas ; and this he values 
 himself upon as a very important discovery. 
 
 We shall have occasion afterwards to 
 examine more particularly this grand prin- 
 ciple of Locke's philosophy, and to shew 
 that it is one of the main pillai's of modern 
 scepticism, although he had no intention to 
 make that use of it. At i)resent let us only 
 consider how it agrees with the instances 
 of belief now under consideration ; and 
 whether it gives any light to them. I be- 
 lieve that the sensation I have exists ; and 
 that the sensation I remember does not 
 now exist, but did exist yesterday. Here, 
 according to Locke's system, I compare the 
 idea of a sensation with the ideas of past 
 and present existence : at one time I per- 
 ceive that this idea agrees with that of j)re- 
 sent existence, but disagrees with that of 
 past existence ; but, at another time, it 
 agrees with the idea of past existence, and 
 disagrees w^ith that of present existence. 
 Truly these ideas seem to be very cajjri- 
 cious in their agreements and disagree- 
 ments. Besides, I cannot, for my heart, 
 conceive what is meant by either. I say 
 a sensation exists, and 1 think I understand 
 clearly what I mean. But you want to 
 make tlie thing clearer, and for that end 
 tell me, that there is an agreement between 
 the idea of that sensation and tlie idea of 
 existence. To sjieak freely, this cdiivoys 
 to me no li^ht, but darkness ; J can con- 
 ceive no otherwise of it, than as an odd and 
 obscure circumlocution. I conclude, tlien,
 
 108 
 
 OF THE HUMAN MIiND, 
 
 that the belief which accompanies sensation 
 and memory, is a simple act of the mind, 
 which cannot be defined. It is, in this 
 respect, like seeing and hearing, wliich can 
 never be so defined as to be understood by 
 those who have not these faculties ; and to 
 such as have them, no definition can make 
 these operations more clear than they are 
 already. In like manner, every man that 
 has any belief — and he must be a curiosity 
 that has none — knows perfectly wliat belief 
 is, but can never define or explain it. I 
 conclude, also, that sensation, memory, and 
 imagination, even where they have the 
 same object, are operations of a quite dif- 
 ferent nature, and perfectly distinguishable 
 by those who are sound and sober. A man 
 that is in danger of confounding them, is 
 indeed to be pitied ; but whatever relief he 
 may find from another art, he can find none 
 from logic or metaphysic. I conclude fur- 
 ther, that it is no less a part of the human 
 constitution, to believe the present existence 
 of our sensations, and to believe the past 
 existence of what we remember, than it is 
 to believe that twice two make four. The 
 evidence of sense, the evidence of memory, 
 and the evidence of the necessary relations 
 of things, are all distinct and original kinds 
 of evidence, equally grounded on our consti- 
 tution : none of them depends upon, or can 
 be resolved into another. To reason against 
 any of these kinds of evidence, is absurd ; 
 nay, to reason for them is absurd. They 
 are first principles ; and such fall not with- 
 in the province of reason,* but of common 
 sense. 
 
 Section VI, 
 
 APOLOGY FOR METAPHYSICAL ABSURDITIES — 
 SENSATION WITHOUT A SENTIENT, A CON- 
 SEQUENCE OF THE THEORY OF IDEAS — 
 CONSEQUENCES OF THIS STRANGE OPINION. 
 
 Having considered the relation which the 
 sensation of smelluig bears to the remem- 
 brance and imagination of it, I proceed to 
 consider what relation it bears to a mind, 
 or sentient principle. It is certain, no man 
 can conceive or believe smelling to exist 
 of itself, without a mind, or something that 
 has the power of smelling, of whicli it is 
 called a sensation, an operation, or feeling. 
 Yet, if any man should demand a proof, 
 that sensation cannot be without a mind or 
 sentient being, I confess that I can give 
 none ; and that to pretend to prove it, seems 
 to me almost as absurd as to deny it. 
 
 This might have been said without any 
 apology before the '• Treatise of Human 
 Nature" appeared in the world. For till 
 
 • See Note f at t). KiO, b — H. 
 
 that time, no man, as far as I know, 
 ever thought either of calling in question 
 that principle, or of giving a reason for his 
 belief of it. Whether thinking beings were 
 of an ethereal or igneous nature, whether 
 material or immaterial, was variously dis- 
 puted ; but that tlmiking is an operation of 
 some kind of being or other, was always 
 taken for granted, as a principle that could 
 not possibly admit of doubt. 
 
 However, since the author above men- 
 tioned, who is undoubtedly one of the most 
 acute metaphysicians that this or any age 
 hath produced, hath treated it as a vulgar 
 prejudice, and maintained that the mind 
 is only a succession of ideas and impres- 
 sions without any subject ; his opinion, 
 however contrary to the common appre- 
 hensions of mankind, deserves respect. I 
 beg therefore, once for all, that no offence 
 may be taken at charging this or other 
 metaphysical notions with absurdity, or 
 with being contrary to the common sense 
 of mankind. No disparagement is meant 
 to the understandings of the authors or 
 maintamers of such opinions. Indeed, they 
 commonly proceed, not from defect of under- 
 standing, but from an excess of refinement 
 the reasoning that leads to them often 
 gives new light to the subject, and shews 
 real genius and deep penetration in the 
 author; and the premises do more than 
 atone for the conclusion. 
 
 If there are certain principles, as I think 
 there are, which the constitution of our 
 nature leads us to believe, and which we 
 are under a necessity to take for granted 
 in the common concerns of life, without 
 being able to give a reason for them — these 
 are what we call the principles of common 
 sense ; and what is manifestly contrary to 
 them, is what we call absurd. 
 
 Indeed, if it is true, and to be received 
 as a principle of philosophy, that sensation 
 and thought may be without a thinking 
 being, it must be acknowledged to be the 
 most wonderful discovery that this or any 
 other age hath produced. The received 
 doctrine of ideas is the principle from which 
 it is deduced, and of which indeed it seems 
 to be a just and natural consequence. And 
 it is probable, that it would not have been 
 so late a discovery, but that it is so shock- 
 ing and repugnant to the common appre- 
 hensions of mankind, that it required an 
 uncommon degree of philosophical intre- 
 pidity to usher it into the world. It is a 
 fundamental principle of the ideal system, 
 that every object of thought must be an 
 impression or an idea — that is, a faint copy 
 of some preceding impression- This is a 
 principle so commonly received, that the 
 author above mentioned, although his whole 
 system is built upon it, never offers the 
 least proof of it. It is upon this principle,
 
 OF SMELLING. 
 
 109 
 
 as a fixed point, that he erects his meta- 
 physical engines, to overturn heaven and 
 earth, body and spirit. And, indeed, in 
 my apprehension, it is altogether sufficient 
 for the purpose. For, if impressions and 
 ideas are the only objects of thought, then 
 heaven and earth, and body and spirit, 
 and everything you please, must signify 
 only impressions and ideas, or they must 
 be words without any meaning. It seems, 
 therefore, that this notion, however strange, 
 is closely connected with the received doc- 
 trine of ideas, and we must either admit the 
 conclusion, or call in question the premises. 
 Ideas seem to have something in their 
 nature unfriendly to other existences. They 
 were first introduced into philosoph}', in 
 the humble character of images or repre- 
 sentatives of things ; and in this chai-acter 
 they seemed not only to be iuofiensive, but 
 to serve admirably well for explaining the 
 operations of the human understanding. 
 But, since men began to reason clearly and 
 distinctly about them, they have by degrees 
 supplanted their constituents, and under- 
 mined the existence of everything but 
 themselves. First, they discarded all se- 
 condary qualities of bodies ; and it was 
 found out by their means, that fire is not 
 hot, nor snow cold, nor honey sweet ; and, 
 in a word, that heat and cold, sound, colour, 
 taste, and smell, are nothing but ideas or 
 impressions. Bishop Berkeley advanced 
 them a step higher, and found out, by just 
 reasoning from the same principles, that 
 extension, solidity, space, figure, and body, 
 are ideas, and that there is nothing in nature 
 but ideas and spirits. But the triumph of 
 ideas was completed by the " Treatise of 
 Human Nature," which discards spirits 
 also, and leaves ideas and mipressions as the 
 sole existences in the universe. What if, at 
 last, having nothing else to contend with, 
 they should fall foul of one another, and 
 leave no existence in nature at all ? This 
 would sure'y bring philosophy into danger ; 
 for what should we have left to talk or to 
 dispute about ? 
 
 However, hitherto these philosophers 
 acknowledge the existence of impressions 
 and ideas ; they acknowledge certain laws 
 ot attraction, or rules of precedence, accord- 
 ing to which, ideas and imjiressions range 
 themselves in various forms, and succeed 
 one another : but that they shoidd belong 
 to a mind, as its jirojier goods and chattels, 
 this they have found to be a vulgar error. 
 These ideas are as free and independent as 
 the birds of the air, or as K])icurus's atoms 
 when they jiursiied their journey in the 
 vast inane. Shall we conci'ive tliem like 
 the films of things in the epicurean system ? 
 I'rincijiio lioc dico, rerum simulacr.i v.ncari, 
 Mulla inodit multis, in cunctan uiMliquc parlcis 
 'I'diuia, qua- f .cile inler kf jungiinlur in auil8, 
 OI)»ia cum vcniiint - -Lulu. 
 
 Or do they rather resemble Aristotle's in- 
 telligible species, after they are shot forth 
 from the object, and before they have yet 
 struck upon the passive intellect ? But why 
 should we seek to compare them with any- 
 thing, since thei*e is nothing in nature but 
 themselves ? They make the whole furni- 
 ture of the universe ; starting into existence, 
 or out of it, without any cause ; combining 
 into parcels, which the vulgar call minds ; 
 and succeeding one another by fixed laws, 
 without time, place, or author of those laws. 
 
 Vet, after all, these self-existent and m- 
 dependent ideas look pitifully naked and 
 destitute, when left thus alone in the uni- 
 verse, and seem, upon the whole, to be in a 
 worse condition than they were before. Des 
 Cartes, Malebranche, and Locke, as they 
 made much use of ideas, treated them hand- 
 somely, and provided them in decent accom- 
 modation ; lodging them either in the pineal 
 gland, or in the pure intellect, or even in 
 the divine mind. They moreover clothed 
 them with a commission, and made them 
 representatives of things, which gave them 
 some dignity and character. But the "Trea- 
 tise of Human Nature," though no less 
 indebted to them, seems to have made but 
 a bad return, by bestowing ujion them this 
 independent existence ; since thereby they 
 are turned out of house and home, and set 
 adrift in the world, without friend or con- 
 nection, without a rag to cover their naked- 
 ness ; and who knows but the whole system 
 of ideas may perish by the indiscreet zeal 
 of their friends to exalt them ? 
 
 However this may be, it is certainly a 
 most amazing discovery that thought and 
 ideas may be \vithout any thinking being 
 — a discovery big with consequences which 
 cannot easily be traced by tliose deluded 
 mortals who think and reason in the com- 
 mon track. We were always apt to ima- 
 gine, that thought supposed a thinker, and 
 love a lover, and treason a traitor : but 
 this, it seems, was all a mistake ; and it is 
 found out, that tlii-re may be treason with- 
 out a traitor, and love without a lover, laws 
 without a legislator, and punishment with- 
 out a sufferer, succession witliout time, and 
 motion without anything moved, or space 
 in which it may move : or if, in these cases, 
 ideas arc the lover, the suti'erer, the traitor, 
 it were to be wished that the author of this 
 discovery had farther condescended to ac- 
 (piaint us whether ideas caii converse to- 
 gether, and be under obligations of duty or 
 gratitude to each other ; whether they can 
 make promises and enti;r into leagues and 
 covenants, and fulfil or break them, and be 
 punished for the breach. If one set of 
 iiloas makes a covenant, another breaks it, 
 and a tliird is punished for it, there is rea- 
 son to think that justice is no natural virtue 
 in this system.
 
 110 
 
 OF THE HUMAN MIND. 
 
 It seemed very natural to tbinlc, that the 
 " Treatise of Human Nature" required an 
 author, and a very ingenious one too ; but 
 now we learn that it is only a set of ideas 
 which came together and arranged them- 
 selves by certain associations and attractions. 
 
 After all, this curious system appears not 
 to be titled to the present state of human 
 nature. How far it may suit some choice 
 spirits, who are refined from the dregs of 
 common sense, I cannot say. It is acknow- 
 ledged, I thinlv, that even these can enter 
 into this system only in their most specula- 
 tive hours, when they soar so high in pur- 
 suit of those self-existent ideas as to lose 
 sight of all other things. But when they 
 condescend to mingle again with the human 
 race, and to converse with a friend, a com- 
 panion, or a fellow-citizen, the ideal system 
 vanishes ; common sense, like an irresist- 
 ible torrent, carries them along ; and, in 
 spite of all their reasoning and philosophy, 
 they believe their own existence, and the 
 existence of other things. 
 
 Indeed, it is happy they do so ; for, if 
 they should carry their closet belief into 
 the world, the rest of mankind would con- 
 sider them as diseased, and send them to 
 an infirmai-y. Therefore, as Plato required 
 certain ])revious qualifications of those who 
 entered his school, I think it would be pru- 
 dent for the doctors of this ideal philosophy 
 to do the same, and to refuse admittance to 
 every man who is so weak as to imagine 
 that he ought to have the same belief in 
 solitude and in company, or that his prin- 
 ciples ought to have any influence upon his 
 practice ; for this philosophy is like a hob- 
 by-horse, which a man in bad health may 
 ride in his closet, without hurting his repu- 
 tation ; but, if he should take him abroad 
 with him to church, or to the exchange, or 
 to the play-house, his heir would imme- 
 diately call a jury, and seize his estate. 
 
 Section VII. 
 
 THE CONCEPTION AND BELIEF OP A SENTIENT 
 BEING OR MIND IS SUGGESTED BY OUR 
 CONSTITUTION — THE NOTION OF RELA- 
 TIONS NOT ALWAYS GOT BY COMPARING 
 THE RELATED IDEAS. 
 
 Leaving this philosophy, therefore, to 
 those who have occasion for it, and can 
 use it discreetly as a chamber exercise, we 
 may still inquire how the rest of mankind, 
 and even the adepts themselves, except in 
 some solitary moments, have got so strong 
 and irresistible a belief, that thought must 
 have a subject, and be the act of some 
 thinking being ; how every man believes 
 himself to be something distinct from his 
 ideas and impressions — something which 
 
 continues the same identical self when all 
 his ideas and im]>ressions are changed. It 
 is impossible to trace the origin of this 
 opinion in history ; for all languages 
 have it interwoven in their original con- 
 struction. All nations have always believed 
 it. The constitution of all laws and 
 governments, as well as the common trans- 
 actions of life, suppose it. 
 
 It is no less impossible for any man to 
 recollect when he himself came by this 
 notion ; for, as far back as we can remem- 
 ber, we were already in possession of it, 
 and as fully persuaded of our own existence, 
 and the existence of other things, as that 
 one and one make two. It seems, there- 
 fore, that this opinion preceded ail reason- 
 ing, and experience, and instruction ; and 
 this is the more probable, because we could 
 not get it by any of these means. It ap- 
 pears, then, to be an undeniable fact, that, 
 from thought or sensation, all mankind, 
 constantly and invariably, from the first 
 dawning of reflection, do infer a power or 
 faculty of thinking, and a permanent being 
 or mind to which that faculty belongs ; and 
 that we as invariably ascribe all the various 
 kinds of sensation and thought we are con- 
 scious of, to one individual mind or self. 
 
 But by what rules of logic we make these 
 inferences, it is impossible to shew ; nay, 
 it is impossible to shew how our sensations 
 and thoughts can give us the very notion 
 and conception either of a mind or of a 
 faculty. The faculty of smelling is some- 
 thing very different from the actual sensa- 
 tion of smelling ; for the faculty may 
 remain when we have no sensation. And 
 the mind is no less difterent from the 
 faculty ; for it continues the same indivi- 
 dual being when that faculty is lost. Yet 
 this sensation suggests to us both a faculty 
 and a mind ; and not only suggests the 
 notion of them, but creates a belief of their 
 existence; although it is impossible to dis- 
 cover, by reason, any tie or connection 
 between one and the other. 
 
 What shall we say, then ? Either those 
 inferences which we draw from our sensa- 
 tions — namely, the existence of a mind, 
 and of powers or fac Ities belonging to it — 
 are prejudices of ])liilosophy or education, 
 mere fictions of the mind, which a wise 
 man should throw off as he does the belief 
 of fairies ; or they are judgments of nature — 
 judgments not got by comparing ideas, and 
 perceiving agreements and disagreements, 
 but immediately inspired by our constitu- 
 tion. 
 
 If this last is the case, as I apprehend it 
 is, it will be impossible to shake off those 
 opinions, and we must yield to them at 
 last, though we struggle hard to get rid of 
 them. And if we could, by a determined 
 obstinacy, shake off the principles of our
 
 OF SMELLING. 
 
 Ill 
 
 nature, this is not to act the philosopher, 
 but the fool or the madman. It is incum- 
 bent upon those who think that these are 
 not natural principles, to shew, in the first 
 place, how we can otherwise get tlie notion 
 of a mind and its faculties ; and then to 
 shew how we come to deceive ourselves 
 into the opinion that sensation cannot be 
 without a sentient beinij. 
 
 It is the received doctrine of philosophers, 
 that our notions of relations can only be 
 got by comparing the related ideas : but, 
 in the present case, there seems to be 
 an instance to the contrary. It is not by 
 having first the notions of mind and sensa- 
 tion, and then comparing them together, 
 that we perceive the one to have the rela- 
 tion of a subject or substratum, and the 
 other that of an act or operation : on the 
 contrary, one of the related things — to wit, 
 sensation — suggests to us both the correlate 
 and the relation. 
 
 I beg leave to make use of the word sii(i- 
 gestion, because I know not one more pro- 
 per, to express a power of the mind, which 
 seems entirely to have escaped the notice 
 of philosophers, and to which we owe 
 many of our simple notions which are 
 neither impressions nor ideas, as well 
 as many original principles of belief. 
 I shall endeavour to illustrate, by an 
 example, what I understand by this word. 
 We all know, that a certain kind of sound 
 suggests immediately to the mind, a coacli 
 passing in the street ; and not only pro- 
 duces the imagination, but the belief, that 
 a coach is passing. Yet there is here no 
 comparing of ideas, no perception of agree- 
 ments or disagreements, to produce this 
 belief: nor is there the least similitude be- 
 tween the sound we hear and the coach we 
 imagine and believe to be passing.* 
 
 * " The word suggest'' (*ay.s Mr Stewart, in p fc. 
 eiice to ilie prpccdiiig lasagc) "is much used by 
 Berkeley, in ihis appiopriate and technical sense, 
 not only in his ' theory of Vision," Imt in his ' Triii- 
 cipUs of Human Knowledge,' and in his ' Minute 
 Philosopher.' It expresses, indeed, the cardinal 
 princi|)le on which his ' 1 heory of Vision' hinges, 
 and is now so incorjiorated with some of our hcst 
 metaphysical speculations, that one catniot easily 
 conceive how the use of it was so long dispenswl 
 with Locke uses tiie word excite for the same 
 punwse; but it seims to imply an hypothc-is con- 
 ccrninK the mechanism of the mind, and by no 
 means expre-ses the tact ill question, with the same 
 force and precision. 
 
 "It is remarkable, th.-it Dr Reid should have fhouaht 
 it iiicumbent on lii'n to .-ipologiso for introducing 
 into plnlosophy a word so fanuliar to every person 
 conversant with Berkeley's works. ' I beg leave 
 lo make use of the word suggestion, because,' 
 
 &c 
 
 "So far Dr I{eid'su«eo( the word coincides ex. 
 actly with thai of Berkeley ; i ut Die former will bo 
 found to annex to it a ine^ining more extensive than 
 the lader, liy e i ploying it to roiiipreheiiil, not only 
 tViiim inlimi ions winch are the n-ult of experience 
 ari'l habit ; hut aiio'her cla-h of inlimiitinns. (r|iiilc 
 overlooked by Berkeley,) those which reiilt from 
 the original frame of the human wumi."— D'lUita. 
 
 It is true that this suggestion is not 
 natural and original ; it is the result of ex- 
 perience and habit. But I think it appears, 
 from what hath been said, that there are 
 natural suggestions : particularly, that sens- 
 ation suggests the notion of present exist- 
 ence, and the belief that what we perceive 
 or feel does now exist ; that memory sug- 
 gests the notion of past existence, and the 
 belief that what we remember did exist in 
 time past ; and that our sensations and 
 thoughts do also suggest the notion of a 
 mind, and the belief of its existence, and of 
 its relation to our thoughts. By a like 
 natural principle it is, that a beginning of 
 existence, or any change in nature, sug- 
 gests to us the notion of a cause, and com- 
 pels our belief of its existence. And, in 
 like maimer, as shall be shewn when we 
 come to the sense of touch, certain sensa- 
 tions of touch, by the constitution of our 
 nature, suggest to us extension, solidity, 
 and motion, which are nowise like fo 
 sensations, although they have been hither- 
 to confounded with them.* 
 
 tiun on the Ilistori/ of Metn/ /ii/sical and Ethical 
 Science. V. 107. Second ediaon 
 
 Mr Stewart ii.ight have adduced, perhaps, a higher 
 and, ccriainly , a more proximae authority, in fa- 
 vour, not merely of the term in general, hut of 
 Kcul's restriited employment of it, as an inlimaiion 
 ot what he and otbeis have designated the Common 
 Sen^e of mankind. The following ,-entence of Ter- 
 tullian contains a singular anticip II ion, I'oth of the 
 philosophy and of the pliilosophiral pbraseoh'gy ol 
 our author. Speaking of the universal belief of 
 the soul's immort;ility : — " Natiira pleraque sjigger. 
 nnlur, quasi de publico srnsu quo animam Ueus di. 
 tare digimtus est." — De Amma, c. H. 
 
 Some strictures en Riid's employment of the term 
 sugifestinn may he seen m the " Versuche" of Tetens, 
 I., p. 5119, sqq — 11. 
 
 • This last sta'enient is not historically correct. 
 But, waving this, there may be ai'iluced, in illustr.a. 
 tioii of ihe two last paragiaplis, the tollowmg 
 remarkable passat;e from St Augustine: — " au. 
 RfCte fortassc exis'imas. Sed respdiide obsecro, 
 utruin omne quod per visrum coguoscimus, videa- 
 mus. Fv. Tta credo, ad. C rcdis etiam omne quod 
 videndo cognoseiinus, per visum nos coginsiere? 
 IV. Kt 111 c credo. At:. Cur ergo p i rumque liimum 
 solum videndo, igiiem subterlalerccngno>cimus quern 
 non videnius? KV Vernni dicis. Kt jam non puto 
 nos videre quicquid |ier visum co'^nnscimus : possu. 
 musenim, ut docuisli, aliu ; videmloaliud cogiioscore 
 qudd visus non attigerit. au Quiil, illud quod per 
 visum seiitimiis,pnssumusneiion videre? i;v. NuHo 
 modo. At) Atiud est ergo neiitiee, ahiid rogims eye, 
 ■ v. Oimiino al'ud, iiam soiitimiis fiaintin (/Dein vide- 
 niu/i, et ex Oil igiiem (juem nan videniu.i, xidie.^.se cog- 
 noscinius. a< . Heue iiitelligis Sed vi les lerteciim 
 hoc accidii, ciri us iio.struMi, id cs' oculos, nihil pati 
 ex igne, sed ex fumo quem solum vidint. H'eiiim 
 videre senlirc, et seiilire pati esse, lam supra eon. 
 sensimus. kv. leneo, *[ as-eniior. Aii. Cum ergo 
 per passionem corporis 11(11 latetal quid ,ii imam, noii 
 cimtinuosensus vocatur unus dequmque memoratis, 
 Si U cum ipsa passio non latet : naiiiquc ille ignis non 
 visus, nee audiius, nee oll.ictus, nee gustatus, ncc 
 laclus a nobis, noil tameii latet animiin fumo vi>o 
 L't cum hoc non latere non vc.eelur .\eiins, quia ex 
 igiie corpus nihil est pa^suin, voiauir lamen cngnilii) 
 tier sen urn, quia ex passinne enrporii (|u.inivis aliu, 
 id est ex alterius rei viswue, eonjietiitum e>t atque 
 C'liiipertum. i v. Intelligo, et uptime video is inl 
 conginere ac lavire ilh deliiulioiii luu". ipiaiii ut 
 nii-am nulil (leleiidendain dedisli: nam iia iiieiiiinl 
 e-se abs te sensum deliniium, cum animam non lali't 
 quod patliur corpus. Itiniue. iltwi (juod/wnut vidoiur.
 
 112 
 
 OV THE HUMAN MIND. 
 
 Section VII f. 
 
 TKEKE IS A QUALITY OR VIRTUE IN BODIES, 
 WHICH WE CALL THEIR SMELL — HOW 
 THIS IS CONNECTED IN THE IMAGINATION 
 AVITH THE SENSATION, 
 
 We have considered smell as signifying 
 a sensation, feeling, or impression upon the 
 mind ; and in this sense, it can only be in 
 a mind, or sentient being : but it is evident 
 that mankind give the name of smc/l much 
 more frequently to something which they 
 conceive to be external, and to be a quality 
 of body : they understand something by it 
 which does not at all infer a mind; and 
 have not the least difficulty in conceiving 
 the air perfumed with aromatic odours in 
 the deserts of Arabia, or in some uninhab- 
 ited island, where the human foot never 
 trod. Every sensible day-labourer hath as 
 clear a notion of this, and as full a convic- 
 tion of the possibility of it, as he hath of 
 his own existence ; and can no more doubt 
 of the one than of the other. 
 
 Suppose that such a man meets with a 
 modern philosopher, and wants to be in- 
 formed what smell in plants is. The phi- 
 losopher tells him, that there is no smell in 
 plants, nor in anything but in the mind ; 
 that it is impossible there can be smell but 
 in a mind ; and that all this hath been 
 demonstrated by modern philosohy. The 
 plain man will, no doubt, be apt to think 
 him merry : but, if he finds that he is 
 serious, his next conclusion will be that he 
 is mad ; or that philosophy, like magic, 
 puts men into a new world, and gives them 
 different faculties from common men. And 
 thus philosophy and common sense are set 
 at variance. But who is to blame for it ? 
 In my opinion the philosopher is to blame. 
 For if he means by smell, what the rest of 
 mankind most commonly mean, he is cer- 
 tainly mad. But if he puts a different 
 meaning upon the word, without observing 
 it himself, or giving warning to others, 
 he abuses language and disgraces philo- 
 sophy, without doing any service to truth : 
 as if a man should exchange the meaning 
 of the words daughter and cow, and then 
 endeavour to prove to his plain neighbour, 
 that his cow is his daughter, and his 
 daughter his cow. 
 
 I believe there is not much more wisdom 
 in many of those paradoxes of the ideal 
 philosopliy, which to plain sensible men 
 appear to be palpable absurdities, but with 
 the adepts pass for profound discoveries. I 
 
 tensum vocatnus ; passi stint enim eum oculi videndo 
 gui stint corporis partes et corpora ; igiiein aittem ex 
 quo nihil corpus est passtim, quamvis cognitiis fuerit, 
 sensiimnon vocamiis. — Uj. Quantitate ANiMiE, c. 
 xxiv. 4 45— H. 
 
 resolve, for my own part, always to pay a 
 great regard to the dictates of common 
 sense, and not to depart from them without 
 absolute necessity : and, therefore, I am 
 apt to think that there is really something 
 in the rose or lily, which is by the vulgar 
 called smell, and which continues to exist 
 when it is not smelled : and shall proceed 
 to inquire what this is ; how we come by 
 the notion of it ; and what relation this 
 quality or virtue of smell hath to the sens- 
 ation which we have been obliged to call 
 by the same name, for want of another. 
 
 Let us therefore suppose, as before, a 
 person beginning to exercise the sense of 
 smelling ; a little experience will discover 
 to him, that the nose is the organ of this 
 sense, and that the air, or something in the 
 air, is a medium of it. And finding, by 
 farther experience, that, when a rose is near, 
 he has a certain sensation, when it is 
 removed, the sensation is gone, he finds a 
 connection in nature betwixt the rose and 
 and this sensation. The rose is considered 
 as a cause, occasion, or antecedent of the 
 sensation ; the sensation as an effect or 
 consequence of the presence of the rose ; 
 they are associated in the mind, and con- 
 stantly found conjoined in the imagination. 
 But here it deserves our notice, that, 
 although the sensation may seem more 
 closely related to the mind its subject, or 
 to the nose its organ, yet neither of these 
 connections operate so powerfully upon the 
 imagination as its connection with the rose 
 its concomitant. The reason of this seems 
 to be, that its connection with the mind is 
 more general, and noway distinguisheth it 
 from other smells, or even fi"om tastes, 
 sounds, and other kinds of sensations. The 
 relation it hath to the organ is likewise 
 general, and doth not distinguish it from 
 other smells ; but the connection it hath 
 with the rose is special and constant ; by 
 which means they become almost insepar- 
 able in the imagination, in like manner as 
 thunder and lightning, freezing and cold. 
 
 Section IX. 
 
 THAT THERE IS A PRINCIPLE IN HUMAN 
 NATURE, FROM WHICH THE NOTION OF 
 THIS, AS WELL AS ALL OTHER NATURAL 
 VIRTUES OR CAUSES, IS DERIVED. 
 
 In order to illustrate further how we 
 come to conceive a quality or virtue in the 
 rose which we call smell, and what this 
 smell is, it is proper to observe, that the 
 mind begins very early to thirst after prin- 
 ciples which may direct it in the exertian 
 of its powers. The smell of a rose is a 
 certain affection or feeling of the mind ; 
 and, as it is not constant, but comes and
 
 OF SMELLING. 
 
 113 
 
 goes, we want to know when and where we 
 may expect it ; and are uneasy till we find 
 something which, being present, brings this 
 feeling along with it, and, being i-emoved, 
 removes it. This, when found, we call the 
 cause of it ; not in a strict and philosophical 
 sense, as if the feeling were really effected 
 or produced by that cause, but in a popular 
 sense ; for the mind is satisfied if there is 
 a constant conjunction between them ; and 
 such causes are in reality nothing else but 
 laws of nature. Havmg found the smell 
 thus constantly conjoined with the rose, the 
 mind is at rest, without inquiring whether 
 this conjunction is owing to a real efficiency 
 or not ; that being a philosophical inquiry, 
 which does not concern human life. But 
 every discovery of such a constant conjunc- 
 tion is of real importance in life, and makes 
 a strong impression upon the mind. 
 
 So ardently do we desire to find everything 
 that happens within our observation thus 
 connected with something else as its cause or 
 occasion, that we are apt to fancy connec- 
 tions upon the slightest grounds ; and this 
 weakness is most remarkable in the ignor- 
 ant, who know least of the real connections 
 established in nature. A man meets with 
 an unlucky accident on a certain day of the 
 year, and, knowing no other cause of his 
 misfortune, he is apt to conceive something 
 unlucky in that day of the calendar ; and, 
 if he finds the same connection hold a second 
 time, is strongly confirmed in his supersti- 
 tion. I remember, many years ago, a white 
 ox was brought into this country, of so 
 enormous a size that people came many 
 miles to see him. There happened, some 
 months after, an uncommon fatality among 
 women in child-bearing. Two such uncom- 
 mon events, following one another, gave a 
 suspicion of their connection, and occasioned 
 a common opinion among the country- 
 people that the white ox was the cause of 
 this fatality. 
 
 However silly and ridiculous this opinion 
 •'as, it sprung from the same root in human 
 nature on which all natural philosophy 
 grows — namely, an eager desire to find out 
 connections in things, and a natural, ori- 
 ginal, and unaccountable propensity to be- 
 lieve that the connections which we have 
 observed in time past will continue in time 
 to come. Omens, portents, good and bad 
 luck, palmistry, astrology, all the numer- 
 ous arts of divination and of interpreting 
 dreams, falhe hypotheses and systems, and 
 true principles in the philosophy of nature, 
 are all built upon the same foundation in 
 the human constitution, and are distin- 
 guished only according as we conclude 
 rashly from trio few instances, or cautiously 
 from a sufiii'ient induction. 
 
 As it is experience only that discovers 
 these connections between natural causes 
 
 and their effects ; without inquiring further, 
 we attribute to the cause some vague and 
 indistinct notion of power or virtue to pro- 
 duce the effect. And, in many cases, the 
 purposes of life do not make it necessary to 
 give distinct names to the cause and the 
 effect. Whence it happens, that, being 
 closely connected in the imagination, al- 
 though very unlike to each other, one name 
 serves for both ; and, in common discourse, 
 is most frequently applied to that which, of 
 the two, is most the object of our attention. 
 This occasions an ambiguity in many words, 
 which, having the same causes in all lan- 
 guages, is common to all, and is apt to be 
 overlooked even by philosophers. Some 
 instances will serve both to illustrate and 
 confirm what we have said. 
 
 Magnetism signifies both the tendency of 
 the iron towards the magnet, and the power 
 of the magnet to produce that tendency ; 
 and, if it was asked, whether it is a quality 
 of the iron or of the magnet, one would per- 
 haps be puzzled at first ; but a little atten- 
 tion would discover, that we conceive a 
 power or virtue in the magnet as the cause, 
 and a motion in the iron as the effect ; and, 
 although these ai'e things quite unlike, they 
 are so united in the imagination, that we 
 give the common name of magnelism to 
 both. The same thing may be said of ynt- 
 vi/aiion, which sometimes signifies the tend- 
 ency of bodies towards the earth, sometimes 
 the attractive power of the earth, which we 
 conceive as the cause of that tendency. We 
 may observe the same ambiguity in some of 
 Sir Isaac Newton's definitions ; and that 
 even in words of his own making. In three 
 of his definitions, he explains very distinctly 
 what he understands by the absolute quan- 
 tity, what by the acceleratvve quantity, and 
 what by the motive quantity, of a centri- 
 petal force. In the first of these three 
 definitions, centripetal force is put for the 
 cause, which we conceive to be some power 
 or virtue in the centre or central body ; in 
 the two last, the same word is put for the 
 effect of this cause, in producing velocity, 
 or in producing motion towards that 
 centre. 
 
 Heat signifies a sensation, and c(d(l a 
 contrary one ; but heal likewise signifies a 
 quality or state of bodies, which hath no 
 contrary, but different degrees. Wlien a 
 man feels the same water hot to one hand 
 and cold to the other, tliis gives him occa- 
 sion to distinguish between the fcling and 
 the heat of the body ; and, although he 
 knows that the sensations are contrary, he 
 does not imagine that tiie body can have 
 contrary qualities at the same time And 
 wlicn he finds a different tMste in the paine 
 body in sickness and in health, he is easily 
 convinced, that tiie (jnality in the body 
 called lasle is the same as before, although 
 
 I
 
 114 
 
 OF THE HUMAN MIND. 
 
 the sensations he has from it are perhaps 
 opposite. 
 
 The vulgar are commonly charged by 
 philosophers, with the absurdity of imagin- 
 ing the smell in the rose to be something 
 like to the sensation of smelling ; but I 
 think unjustly ; for they neither give the 
 same epithets to both, nor do they reason 
 in the same manner from them. What is 
 smell in the rose ? It is a quality or vir- 
 tue of the rose, or of something proceeding 
 from it, which we perceive by the sense of 
 smelling ; and this is all we know of the 
 matter. But what is smelling ? It is an 
 act of the mind, but is never imagined to 
 be a quality of the mind. Again, the sens- 
 ation of smelling is conceived to infer neces- 
 sarily a mind or sentient being ; but smell 
 in the rose infers no such thing. We say, 
 this body smells sweet, that stinks ; but we 
 do not say, this mind smells sweet and that 
 stinks. Therefore, smell in the rose, and 
 the sensation which it causes, are not con- 
 ceived, even by the vulgar, to be things of 
 the same kind, although they have the same 
 name. 
 
 From what hath been said, we may learn 
 that the smell of a rose signifies two 
 things : First, a sensation, which can have 
 no existence but when it is perceived, and 
 can only be in a sentient being or mind ; 
 Secondly, it signifies some power, quality, 
 or virtue, in the rose, or in effluvia proceed- 
 ing from it, which hath a permanent exist- 
 ence, independent of the mind, and which, 
 by the constitution of nature, produces 
 the sensation in us. By the original con- 
 stitution of our nature, we are both led to 
 believe that there is a permanent cause of 
 the sensation, and prompted to seek after 
 it ; and experience determines us to place 
 it in the rose. The names of all smells, 
 tastes, sounds, as well as heat and cold, 
 have a like ambiguity in all languages ; 
 but it deserves our attention, that these 
 names are but rarely, in common language, 
 used to signify the sensations ; for the most 
 part, they signify the external qualities 
 which are indicated by the sensations — the 
 cause of which phenomenon It take to be 
 this. Our sensations have very different 
 degrees of strength. Some of them are so 
 quick and lively as to give us a great deal 
 either of pleasure or of uneasiness. When 
 this is the case, we are compelled to attend 
 to the sensation itself, and to make it an 
 object of thought and discourse ; we give it 
 a name, which signifies nothing but the 
 sensation ; and in this case we readily 
 acknowledge, that the thing meant by that 
 name is in the mind only, and not in any- 
 thing external. Such are the various kinds 
 of pain, sickness, and the sensations of 
 hunger and other appetites. But, where 
 the sensation is not so interesting as to re- 
 
 quire to be made an object of thought, our 
 constitution leads us to consider it as a 
 sign of something external, which hath a 
 constant conjunction with it; and, having 
 found what it indicates, we give a name to 
 that : the sensation, having no proper 
 name, falls in as an accessory to the thing 
 signified by it, and is confounded under the 
 same name. So that the name may, in- 
 deed, be applied to the sensation, but most 
 properly and commonly is applied to the 
 thing indicated by that sensation. The 
 sensations of smell, taste, sound, and colour, 
 are of infinitely more importance as signs 
 or indications, than they are upon their own 
 account ; like the words of a language, 
 wherein we do not attend to the sound but 
 to the sense. 
 
 Section X. 
 
 WHETHER IN SENSATION THE MIND IS ACTIVE 
 OR PASSIVE ? 
 
 There is one inquiry remains. Whether, 
 in smelling, and in other sensations, the 
 mind is active or passive ? This possibly 
 may seem to be a question about words, or, 
 at least, of very small importance ; how- 
 ever, if it leads us to attend more accu- 
 rately to the operations of our minds than 
 we are accustomed to do, it is, upon that 
 very account, not altogether unprofitable. 
 I think the opinion of modern philosophers 
 is, that in sensation the mind is altogether 
 passive.* And this undoubtedly is so far 
 true, that we cannot raise any sensation in 
 our minds by willing it ; and, on the other 
 hand, it seems hardly possible to avoid 
 liaving the sensation when the object is 
 presented. Yet it seems likewise to be 
 true, that, in proportion as the attention is 
 more or less turned to a sensation or 
 diverted from it, that sensation is more or 
 less perceived and remembered. Every 
 one knows that very intense pain may be 
 diverted by a surprise, or by anything that 
 entirely occupies the mind. When we are 
 engaged in earnest conversation, the clock 
 may strike by us without being heard ; at 
 least, we remember not, the next moment, 
 that we did hear it. The noise and tumult 
 of a great trading city is not heard by 
 them who have lived in it all their days ; 
 but it stuns those strangers who have 
 lived in the peaceful retirement of the 
 country. Whether, therefore, there can 
 be any sensation where the mind is purely 
 passive, I will not say ; but I think we are 
 conscious of having given some attention 
 to every sensation which we remember, 
 though ever so recent. 
 
 • 71i\s U far too absolutely stated.— H.
 
 OF TASTING. 
 
 115 
 
 No doubt, where the impulse is strong 
 and uncommon, it is as difficult to withhold 
 attention as it is to forbear crying out in 
 racking pain, or starting in a sudden fright. 
 But how far both might be attained by 
 strong resolution and practice, is not easy 
 to determine. So that, although the Peri- 
 patetics had no good reason to suppose an 
 active and a passive intellect, since atten- 
 tion may be well enough accounted an act 
 of the will, yet I think they came nearer 
 10 the truth, in holding the mind to be in 
 sensation partly passive and partly active, 
 than the moderns, in affirming it tot be 
 purely passive. Sensation, imagination, 
 memory, and judgment, have, by the vulgar 
 in all ages, been considered as acts of the 
 mind. The manner in which they are ex- 
 pressed in all languages, shews this. When 
 the mind is much employed in them, we 
 say it is very active ; whereas, if they were 
 impressions only, as the ideal philosophy 
 would lead us to conceive, we ought, in such 
 a case, rather to say, that the mind is very 
 passive ; for, I suppose, no man would 
 attribute great activity to the paper I write 
 upon, because it receives variety of cha- 
 racters. 
 
 The relation which the sensation of smell 
 bears to the memory and imagination of it, 
 and to a mind or subject, is common to all 
 our sensations, and, indeed, to all the oper- 
 ations of the mind : the relation it bears to 
 the will is common to it with all the powers 
 ofhinderstanding ; and the relation it bears to 
 that quality or virtue of bodies which it in- 
 dicates, is common to it with the sensa- 
 tions of taste, hearing, colour, heat, and 
 cold — so that what hath been said of this 
 sense, may easily be applied to several of 
 our senses, and to other operations of the 
 mind ; and this, I hope, will apologize for 
 our insisting so long upon it. 
 
 CHAPTER III. 
 
 OF TASTING. 
 
 A GREAT part of what hath been said of 
 tlie sense of smelling, is so easily applied 
 to tlioso of tasting and hearing, that we 
 shall leave the application entirely to the 
 reader's judgment, and save ourselves the 
 trouble of a tedious repetition. 
 
 It is probable that everything that affects 
 the taste is, in some degree, soluble in the 
 suliva. It is not conceivable how anything 
 should enter readily, and of its own accord, 
 as it were, into the pores of the tongue, 
 [laJate, and friucm, unless it had some 
 clioniical affinity to that lif|uor with which 
 tlicso pores are always rcjilete. It is, there 
 fore, an admirable contrivance of nature, 
 that the organs of taste should always be 
 
 moist with a liquor which is so universal a 
 menstruum, and which deserves to be ex- 
 amined more than it hath been hitherto, 
 both in that capacity, and as a medical 
 unguent. Nature teaches dogs, and other 
 animals, to use it in this last way ; and its 
 subserviency both to taste and digestion 
 shews its efficacy in the former. 
 
 It is with manifest design and propriety, 
 that the organ of this sense guards the 
 entrance of the alimentary canal, as that of 
 smell the entrance of the canal for respira- 
 tion. And from these organs being placed in 
 such manner that everything that enters into 
 the stomach must undergo the scrutiny of 
 both senses, it is plain that they were intended 
 by nature to distinguish wholesome food 
 from that which is noxious. The brutes 
 have no other means of choosing their food ; 
 nor would mankind, in the savage state. 
 And it is very probable that the smell and 
 taste, noway vitiated by luxury or bad 
 habits, would rarely, if ever, lead us to a 
 wrong choice of food among the produc- 
 tions of nature ; although the artificial 
 compositions of a refined and luxurious 
 cookery, or of chemistry and pharmacy, 
 may often impose upon both, and produce 
 things agreeable to the taste and smell, 
 which are noxious to health. And it is 
 probable that both smell and taste are 
 vitiated, and rendered less fit to perform 
 their natural offices, by the unnatural kmd 
 of life men commonly lead in society. 
 
 These senses are likewise of great use to 
 distinguish bodies that cannot be distin- 
 guished by our other senses, and to discern 
 the changes which the same body under- 
 goes, which, in many cases, are sooner per- 
 ceived by taste and smell than by any other 
 means. How many things are there in the 
 market, the eating-house, and the tavern, 
 as well as in the apothecary and chemist's 
 sliops, which are known to be what they 
 are given out to be, and are percei^•ed to be 
 good or bad in their kind, only by taste 
 or smell ? And how far our judgment of 
 things, by means of our senses, might bo 
 improved by accurate attention to the small 
 difl'crences of taste and smell, and other 
 sensible qualities, is not easy to determine. 
 Sir Isaac Newton, by a noble effort of his 
 great genius, attempted, from the colour 
 of opaque bodies, to discover tlie magnitude 
 of the minute ]icllucid parts of which they 
 are compounded : and who knows what 
 new lights natural philosophy may yet re- 
 ceive from other secondary qualities duly 
 examined ? 
 
 Some tastes and smells stinudato the 
 iKTvos and raise the spirits : but such an 
 artificial elevation of the spirits is, by the 
 laws of nature, followed ))y a depression, 
 which can only be relieved by time, or by 
 thd repeated use of the like s/imu/tj.i. By 
 
 I '2
 
 116 
 
 OF THE HUMAN MIND. 
 
 the use of such things we create an appe- 
 tite for them, which very much resembles, 
 and hath all the force of a natural oue. It 
 is in this manner that men acquire an ap- 
 petite for snuff, tobacco, strong liquors, 
 laudanuan, and the like. 
 
 Nature, indeed, seems studiously to have 
 set bounds to the pleasures and pains we 
 have by these two senses, and to have con- 
 fined them within very narrow limits, that 
 we might not place any part of our happi- 
 ness in them ; there being hardly any 
 smell or taste so disagreeable that use will 
 not make it tolerable, and at last perhaps 
 agreeable, nor any so agreeable as not to 
 lose its relish by constant use. Neither is 
 there any pleasure or pain of these senses 
 which is not introduced or followed by 
 some degree of its contrary, which nearly 
 balances it ; so that we may here apply 
 the beautiful allegory of the divine So- 
 crates — that, although pleasure and pain 
 are contrary in their nature, and their faces 
 look different ways, yet Jupiter hath tied 
 them so together that he that lays hold of 
 the one draws the other along with it. 
 
 As there is a great variety of smells, 
 seemingly simple and uncompounded, not 
 only altogether unlike, but some of them 
 contrary to others, and as the same thing 
 may be said of tastes, it would seem that 
 oue taste is not less different from another 
 than it is from a smell : and therefore it 
 may be a question, how all smells come 
 to be considered as one penus, and all 
 tastes as another ? What is the generical 
 distinction ? Is it only that the nose is the 
 organ of the one and the palate of the 
 other ? or, abstracting from the organ, is 
 there not in the sensations themselves 
 something common to smells, and some- 
 thing else common to tastes, whereby the 
 one is distinguished from the other ? It 
 seems most probable that the latter is the 
 case ; and that, under the appearance of 
 the greatest simplicity, there is still in 
 these sensations something of composition. 
 
 If one considers the matter abstractly, it 
 would seem that a number of sensations, 
 or, indeed, of any other individual things, 
 which are perfectly simple and uncom- 
 pounded, are incapable of being reduced 
 into genera and species ; because individuals 
 which belong to a species must have some- 
 thing peculiar to each, by which they are 
 distinguished, and something common to 
 the whole species. And the same may be 
 said of species which belong to one genus. 
 And, whether this does not imply some kind 
 of composition, we shall leave to metaphy- 
 sicians to determine. 
 
 The sensations both of smell and taste do 
 undoubtedly admit of an immense variety 
 of modifications, which no language can 
 express. If a man was to examine five 
 
 hundred different wines, he would hardly 
 find two of them that had precisely the 
 same taste. The same thing holds in cheese, 
 and in many other things. Yet, of five 
 hundred different tastes in cheese or wme, 
 we can hardly describe twenty, so as to give 
 a distinct notion of them to one who had 
 not tasted them. 
 
 Dr Nehemiah Grew, a most judicious 
 and laborious naturalist, in a discourse read 
 before the Royal Society, anno 1675, hath 
 endeavoured to shew that there are at least 
 sixteen different simple tastes, which he 
 enumerates.* How many compounded 
 ones may be made out of all the various 
 combinations of two, three, four, or more 
 of these simple ones, they who are ac- 
 quainted with the theory of combinations 
 will easily perceive. All these have va- 
 rious degrees of intenseness and weakness. 
 Many of them have other varieties ; in some 
 the taste is more quickly perceived upon 
 the application of the sapid body, in others 
 more slowly — in some the sensation is more 
 permanent, in others more transient — in 
 some it seems to undulate or return after 
 certain intervals, in othei's it is constant ; 
 the various parts of the organ — as the lips, 
 the tip of the tongue, the root of the tongue, 
 the fauces, the uvula, and the throat — are 
 some of them chiefly affected by one sapid 
 body, and others by another. All these, 
 and other varieties of tastes, that accurate 
 writer illustrates by a number of examples. 
 Nor is it to be doubted, but smells, if exa- 
 mined with the same accuracy, would appear 
 to have as great variety. 
 
 CHAPTER IV. 
 
 OF HEAUIXG. 
 
 Section I. 
 
 VARIETY OF SOUNDS — THEIR PLACE AND 
 DISTANCE LEARNED BY CUSTOM, WITHOUT 
 REASONING. 
 
 Sounds have probably no less variety of 
 modifications, than either tastes or odours. 
 For, first, sounds differ in tone. The ear 
 is capable of perceiving four or five hun- 
 dred variations of tone in souud, and pro- 
 bably as many different degrees of strength ; 
 by combining these, we have above twenty 
 thousand simple sounds that differ either 
 in tone or strength, supposing every tone 
 to be perfect. But it is to be observed, 
 that to make a perfect tone, a great many 
 
 • Plato and Galen reckon seven, Aristotle and 
 Theophrastus eight species of simple tastes Among 
 the moderns, (as 1 recollect,) these are estimated at 
 ten, by Boerhaave and Linnaeus ; by Haller, at 
 twelve.—H.
 
 OF HEARING. 
 
 117 
 
 undulations of elastic air are required, 
 which must all be of equal duration and 
 extent, and follow one another with perfect 
 regularity ; and each undulation must be 
 made up of the advance and recoil of in- 
 immerable particles of elastic air, whose 
 motions are all uniform in direction, force, 
 and time. Hence we may easily conceive 
 a prodigious variety in the same tone, aris- 
 ing from irregularities of it, occasioned by 
 the constitution, figure, situation, or man- 
 ner of striking the sonorous body ; from 
 the constitution of the elastic meduim, 
 or its being disturbed by other motions ; 
 and from the constitution of the ear itself, 
 upon which the impression is made. 
 
 A flute, a violin, a hautboy, and a French 
 horn, may all sound the same tone, and be 
 easily distinguishable. Nay, if twenty 
 human voices sound the same note, and 
 with equal strength, there will still be some 
 difference. The same voice, while it re- 
 tains its proper distinctions, may yet be 
 varied many ways, by sickness or health, 
 youth or age, leanness or fatness, good or 
 bad humour. The same words spoken by 
 foreigners and natives — nay, by persons of 
 different provinces of the same nation — may 
 be distinguished. 
 
 Such an immense variety of sensations 
 of smell, taste, and sound, surely was not 
 given us in vain. They are signs by which 
 we know and distinguish things without 
 us ; and it was fit that the variety of the 
 signs should, in some degree, correspond 
 with the variety of the things signified by 
 them. 
 
 It seems to be by custom that we learn 
 to distinguish both the place of things, and 
 their nature, by means of their sound. 
 That such a noise is in the street, such 
 another in the room above me ; that this 
 is a knock at my door, that a person walk- 
 ing up stairs — is probably learnt by expe- 
 rience. I remember, that once lying a- 
 bed, and having been jnit into a fright, I 
 heard my own heart beat ; but I took it 
 to be one knocking at the door, aud arose 
 and opened the door oftener than once, 
 before I discovered that the sound was in 
 my own breast. It is probable, that, pre- 
 vious to all experience, we should as little 
 know whether a sound came from the 
 right or left, from above or below, from 
 a great or a small distance, as we should 
 know whether it was the sound of a drum, 
 or a bell, or a cart. Nature is frugal in 
 her operations, and will not be at the ex- 
 pense of a particular instinct, to give us 
 that knowledge which experience will soon 
 produce, by means of a general principle of 
 human nature. 
 
 For a little experience, by the constitu- 
 tion of human nature, ties together, not 
 only in our imagination, but in our belief. 
 
 those thhigs which were in their nature un- 
 connected. When I hear a certain sound, 
 I conclude immediately, without reasoning, 
 that a coach passes by. There are no pre- 
 mises from which this conclusion is iuferred 
 by any rules of logic. It is the effect of a 
 principle of our nature, common to us with 
 the brutes. 
 
 Although it is by hearing that we are 
 capable of the perceptions of harmony and 
 melody, and of all the charms of nmsie, 
 yet it would seem that these require a 
 higher faculty, which we call a musical e a f. 
 This seems to be in very different degrees, 
 in those who have the bare faculty of hear- 
 ing equally perfect ; and, therefore, ought 
 not to be classed with the external senses, 
 but in a higher order. 
 
 Section II. 
 
 OF NATURAL LANGUAGE. 
 
 One of the noblest purposes of sound un- 
 doubtedly is language, without which man- 
 kind would hardly be able to attain any 
 degree of improvement above the brutes. 
 Language is commonly considered as purely 
 an invention of men, who by nature are 
 no less mute than the brutes ; but, having 
 a superior degree of invention and reason, 
 have been able to contrive artificial signs 
 of their thouglits and purposes, and to es- 
 tablish them by common consent. But the 
 origin of language deserves to be more care- 
 fully inquired into, not only as this inquiry 
 may be of importance for the improvement 
 of language, but as it is related to the pre- 
 sent subject, and tends to lay open some 
 of the first principles of human nature. I 
 shall, therefore, offer some thoughts upon 
 this subject. 
 
 By language I understand all those signs 
 which mankind use in order to communi- 
 cate to others their thoughts and intentions, 
 their purposes and desires. And such 
 signs may be conceived to be of two kinds : 
 First, such as have no meaning but what 
 is affixed to them by compact or agreement 
 among those who use them — these are ar- 
 tificial signs ; Secondly, such as, previous 
 to all compact or agreement, have a mean- 
 ing which every man understands by the 
 principles of his nature. Language, so far 
 as it consists of artificial signs, may be called 
 artificial ,• so far as it consists of natural 
 signs, I call it natural. 
 
 Having premised these definitions, I 
 think it is demonstrable, that, if mankind 
 had not a natural language, they could 
 never have invented an artificial one by 
 their reason and ingenuity. For all arti- 
 ficial language su|)poKeB some com|)act or 
 agreement to affix a certain meaning to
 
 118 
 
 OF THE HUMAN MIND. 
 
 certain signs ; therefore, there must be 
 compacts or agreements before the use of 
 artificial signs ; but there can be no com- 
 pact or agreement witliout signs, nor with- 
 out language ; and, therefore, tliere must 
 be a natural language before any artificial 
 language can be invented : which was to 
 be demonstrated. 
 
 Had language in general been a human 
 invention, as much as writing or printing, 
 we should find whole nations as mute as 
 the brutes. Indeed, even the brutes have 
 some natural signs by which they express 
 their own thoughts, affections, and desires, 
 and understand those of others. A chick, 
 as soon as hatched, understands the differ- 
 ent sounds whereby its dam calls it to food, 
 or gives the alarm of danger. A dog or a 
 horse understands, by nature, when the 
 human voice caresses, and when it threatens 
 him. But brutes, as far as we know, have 
 no notion of contracts or covenants, or of 
 moral obligation to perform them. If na- 
 ture had given them these notions, she 
 would probably have given them natural 
 signs to express them. And where nature 
 has denied these notions, it is as impossible 
 to acquire them by art, as it is for a blind 
 man to acquire the notion of colours. Some 
 brutes are sensible of honour or disgrace ; 
 they have resentment and gratitude ; but 
 none of them, as far as we know, can make 
 a promise or plight their faith, having no 
 such notions from their constitution. And 
 if mankind had not these notions by nature, 
 and natural signs to express them by, with 
 all their wit and ingenuity they could never 
 have invented language. 
 
 The elements of this natural language 
 of mankind, or the signs that are naturally 
 expressive of our thoughts, may, I think, 
 be reduced to these three kinds : modula- 
 tions of the voice, gestures, and features. 
 By means of these, two savages who have 
 no common artificial language, can converse 
 together ; can communicate their thoughts 
 in some tolerable manner ; can ask and 
 refuse, afiirm and deny, threaten and sup- 
 plicate ; can traffic, enter into covenants, 
 and plight their faith. This might be con- 
 firmed 1)y historical facts of undoubted 
 credit, if it were necessary. 
 
 Mankind having thus a common language 
 by nature, though a scanty one, adapted 
 only to the necessities of nature, there is 
 no great ingenuity required in improving 
 it by the addition of artificial signs, to 
 supply the deficiency of the natural. These 
 artificial signs must multiply with the arts 
 of life, and the improvements of knowledge. 
 The articulations of the voice seem to be, 
 of all signs, the most proper for artificial 
 language ; and as mankind have universally 
 used them for that purpose, we may reason- 
 ably judge that nature intended them for it. 
 
 But nature probably does not intend that 
 we should lay aside the use of the natural 
 signs ; it is enough that we supply their 
 defects by artificial ones. A man that rides 
 always in a chariot, by degrees loses the 
 use of his legs ; and one who uses artificial 
 signs only, loses both the knowledge and 
 use of the natural. Dumb people retain 
 much more of the natural language than 
 others, because necessity obliges them to 
 use it. And for the same reason, savages 
 have much more of it than civilized nations. 
 It is by natural signs chiefly that we give 
 force and energy to language ; and the less 
 language has of them, it is the less ex- 
 pressive and persuasive. Thus, writing Ls 
 less expressive than reading, and reading 
 less expressive than speaking without book ; 
 speaking without the proper and natural 
 modulations, force, and variations of the 
 voice, is a frigid and dead language, com- 
 pared with that which is attended with 
 them ; it is still more expressive when we 
 add the language of the eyes and features ; 
 and is then only in its perfect and natural 
 state, and attended with its proper energy, 
 when to all these we superadd the force of 
 action. 
 
 Where speech is natural, it will be an 
 exercise, not of the voice and lungs only, 
 but of all the muscles of the body ; like 
 that of dumb people and savages, whose 
 language, as it has more of nature, is more 
 expressive, and is more easily learned. 
 
 Is it not pity that the refinements of a 
 civilized life, instead of supplying the de- 
 fects of natural language, should root it 
 out and plant in its stead dull and lifeless 
 articulations of unmeaning sounds, or the 
 scrawling of insignificant characters ? The 
 perfection of language is commonly thought 
 to be, to express human thoughts and sen- 
 timents distinctly by these dull signs ; but 
 if this is the perfection of artificial language, 
 it is surely the corruption of the natural. 
 
 Artificial signs signify, but they do not 
 express ; they speak to the understanding, 
 as algebraical characters may do, but the 
 passions, the affections, and the will, hear 
 them not : these continue dormant and 
 inactive, till we speak to them in the lan- 
 guage of nature, to which they are all atten- 
 tion and obedience. 
 
 It were easy to shew, that the fine arts 
 of the musician, the painter, the actor, and 
 the orator, so far as they are expressive — 
 although the knowledge of them requires 
 in us a delicate taste, a nice judgment, and 
 much study and practice — yet they are 
 nothing else but the language of nature, 
 which we brought into the world with us, 
 but have unlearned by disuse, and so find 
 the greatest difficulty in recovering it. 
 
 Abolish the use of articulate sounds and 
 writing among mankind for a century.
 
 OF TOUCH. 
 
 119 
 
 and every man would be a painter, an 
 actor, and an orator. We mean not to 
 afBrra that such an expedient is practica- 
 ble ; or, if it were, that the advantage 
 would counterbalance the loss ; but that, 
 as men are led by nature and necessity to 
 converse together, they will use every mean 
 in their power to make themselves under- 
 stood ; and where they cannot do this by 
 artificial signs, they will do it, as far as 
 possible, by natural ones : and he that 
 understands perfectly the use of natural 
 signs, must be the best judge in all the ex- 
 pressive arts. 
 
 CHAPTER V. 
 
 OF TOUCH. 
 
 Section I. 
 
 OF HEAT AND COLD. 
 
 The senses which we have hitherto con- 
 sidered, are very simple and uniform, each 
 of them exhibiting only one kind of sensa- 
 tion, and thereby indicating only one quality 
 of bodies. By the ear we perceive sounds, 
 and nothing else ; by the palate, tastes ; 
 and by tlie nose, odours. These qualities 
 are all likewise of one order, being all 
 secondary qualities ; whereas, by touch we 
 perceive not one quality only, but many, 
 and those of very different kinds.* The 
 chief of them are heat and cold, hardness 
 and softness, roughness and smoothness, 
 figure, solidity, motion, and extension. 
 "We shall consider these in order. 
 
 As to heat and cold, it will easily be 
 allowed that they are secondary qualities, 
 of the same order with smell, taste, and 
 sound. And, therefore, what hath been 
 already said of smell, is easily applicable to 
 them ; that is, tliat the words heat and cold 
 have each of them two significations ; thoy 
 sometimes signify certain sensations of the 
 mind, which can have no existence when 
 when they are not felt, nor can exist any- 
 where but in a mind or sentient being ; but 
 more frequently they signify a quality in 
 bodies, which, by the laws of nature, occa- 
 sions the sensations of heat and cold in us — 
 a quality which, though connected by cus- 
 tom so closely with the sensation, that we 
 cannot, without difficulty, separate them, 
 yet hath not the least resemblance to it. 
 
 • It has been very cnmmonly held by philosophers, 
 both in ancient and moilern times, that the division 
 of the senses into live, is altugethor inadequate ; and 
 P';chologi8tB, thouRh not at one in regard to the dis. 
 Iribution, arc now generally ngrecd, that under Touch 
 — or FcelinK, in the.strictcst signification (■! the term 
 — are coinprikeil perrei)tioin which are, at least, aK 
 well entitled to be 0|. posed inspeeies, a« those of 'J'aste 
 and Smell — il. 
 
 and may continue to exist when there is no 
 sensation at all. 
 
 The sensations of heat and cold are per- 
 fectly loiown ; for they neither are, nor can 
 be, anj-thing else than what we feel them 
 to be ; but the qualities in bodies which we 
 call heat and cold, are unknown. They are 
 only conceived by us, as unknown causes or 
 occasions of the sensations to which we give 
 the same names. But, though common 
 sense says nothing of the nature of these 
 qualities, it plainly dictates the existence of 
 them ; and to deny that there can be heat 
 and cold when they are not felt, is an ab- 
 surdity too gross to merit confutation. For 
 what could be more absurd, than to say, 
 that the thermometer cannot rise or fall, 
 unless some person be present, or that the 
 coast of Guinea would be as cold as Nova 
 Zembla, if it had no inhabitants ? 
 
 It is the business of philosophers to in- 
 vestigate, by proper experiments and in- 
 duction, what heat and cold are in bodies. 
 And whether they make heat a particular 
 element diffused through nature, and ac- 
 cumulated in the heated body, or whether 
 they make it a certain vibration of the 
 parts of the heated body ; whether they de- 
 termine that heat and cold are contrary 
 qualities, as the sensations undoubtedly are 
 contrary, or that heat only is a quality, 
 and cold its privation : these questions are 
 within the province of philosophy ; for com- 
 mon sense says nothing on the one side or 
 the other. 
 
 But, whatever be the nature of that 
 quality in bodies which we call hrat, we 
 certainly know this, that it cannot in the 
 least resemble the sensation of heat. It is 
 no less absurd to suppose a likeness be- 
 tween the sensation and the quality, than 
 it would be to suppose that the pain of 
 the gout resembles a square or a triangle. 
 The simplest man that hath common sense, 
 does not imagine the sensation of heat, or 
 anything that resembles that sensation, to 
 be in the fire. He only imagines that 
 there is something in the fire which makes 
 him r.nJ other sentient beings feel heat. 
 Yet, as the name of heat, in common lan- 
 guage, more frequently and more properly 
 signifies this unknown something in the 
 fire, than the sensation occasioned by it, 
 he justly laughs at the pliilosopher who 
 denies that there is any heat in the fire, 
 and thinks that he speaks contrary to com- 
 mon sense. 
 
 Srrlion II. 
 
 OK HAKDNKSS AM! SOFTNKSS. 
 
 Let UH next cotisider hardncsa and soft- 
 ness ; by wliicli words we always under-
 
 120 
 
 OF THE HUMAN MIND. 
 
 stand real properties or qualities of bodies 
 of which we have a distinct conception. 
 
 When the parts of a body adhere so firmly 
 that it cannot easily be made to change its 
 fit^ure, we call it lidid ; v\'lien its parts are 
 e^ily displaced, we call it soft. This is the 
 notion which all mankind have of hardness 
 and softness ; they are neither sensations, 
 nor like any sensation; they were real 
 qualities before they were perceived by 
 touch, and continue to be so when they are 
 not perceived ; for if any man will affirm 
 that diamonds were not hard till they were 
 handled, who would reason with hun ? 
 
 There is, no doubt, a sensation by which 
 we perceive a body to be hard or soft. This 
 sensation of hardness may easily be had, by 
 pressing one's hand against the table, and 
 attending to the feeling that ensues, setting 
 aside, as much as possible, all thought of the 
 table and its qualities, or of any external 
 thing. But it is one thing to have the sens- 
 ation, and another to attend to it, and make 
 it a distinct object of reflection. The first 
 is very easy ; the last, in most cases, ex- 
 tremely difficult. 
 
 We are so accustomed to use the sensa- 
 tion as a sign, and to pass immediately to the 
 hardness signified, that, as far as appears, it 
 wasnever made an object of thought, either 
 by the vulgar or by philosophers ; nor has it a 
 name in any language. There is no sensation 
 more distinct, or more frequent ; yet it is 
 never attended to, but passes through the 
 mind instantaneously, and serves only to 
 introduce that quality in bodies, which, by a 
 law of our constitution, it suggests. 
 
 There are, indeed, some cases, wherein 
 it is no difficult matter to attend to the sens- 
 ation occasioned by the hardness of a body; 
 for instance, when it is so violent as to occa- 
 sion considerable pain : then nature calls 
 upon us to attend to it, and tlien we acknow- 
 ledge that it is a mere sensation, and can 
 only be in a sentient being. If a man runs 
 his head with violence against a pillar, I 
 appeal to him whether the pain he feels re- 
 sembles the hardness of the stone, or if he 
 can conceive anything like what he feels to 
 be in an inanimate piece of matter. 
 
 The attention of the mind is here entirely 
 turned towards the painful feeling ; and, to 
 speak in the common language of mankind, 
 he feels nothing in the stone, but feels a 
 violent pain in his head. It is quite other- 
 wise when he leans his head gently against 
 the pillar ; for then he will tell you that he 
 feels nothing in his head, but feels hardness 
 in the stone. Hath he not a sensation in 
 this case as well as in the other ? Un- 
 doubtedly he hath ; but it is a sensation 
 which nature intended only as a sign of 
 something in the stone ; and, accordingly, 
 he instantly fixes his attention upon the 
 thing signified ; and cannot, without great 
 
 difficulty, attend so much to the sensation 
 as to be persuaded that there is any such 
 thing distinct from the hardness it signifies. 
 But, however difficult it may be to attend 
 to this fugitive sensation, to stop its rapid 
 progress, and to disjoin it from the external 
 quality of hardness, in whose shadow it is 
 apt inmiediately to hide itself ; this is what 
 a philosopher by pains and practice must 
 attain, otherwise it will be impossible for 
 him to reason justly upon this subject, or 
 even to understand what is here advanced. 
 For the last appeal, in subjects of this na- 
 ture, nnist be to what a man feels and per- 
 ceives in his own mind. 
 
 It is indeed strange that a sensation 
 which we have every time we feel a body 
 hard, and which, consequently, we«an com- 
 mand as often and continue as long as we 
 please, a sensation as distinct and determi- 
 nate as any other, should yet be so much 
 unknown as never to have been made an 
 object of thought and reflection, nor to 
 have been honoured with a name in any 
 language ; that philosophers, as well as the 
 vulgar, should have entirely overlooked it, 
 or confounded it with that quality of bo- 
 dies which we call hardness, to which it 
 hath not the least similitude. May we not 
 hence conclude, that the knowledge of the 
 human faculties is but in its infancy ? — 
 that we have not yet learned to attend to 
 those operations of the mind, of which we 
 are conscious every hour of our lives ? — 
 that there are habits of inattention ac- 
 quired very early, which are as hard to be 
 overcome as other habits ? For I think it 
 is probable, that the novelty of this sensa- 
 tion will procure some attention to it in 
 children at first ; but, being in nowise inte- 
 rest mg in itself, as soon as it becomes 
 familiar, it is overlooked, and the attention 
 turned solely to that which it signifies. 
 Thus, when one is learning a language, he 
 attends to the sounds ; but when he is mas- 
 ter of it, he attends only to the sense of 
 what he would express. If this is the case, 
 we must become as little children again, if 
 we will be philosophers ; we must over- 
 come this habit of inattention which has 
 been gathering strength ever since we 
 began to think — a habit, the usefulness of 
 which, in common life, atones for the dif- 
 ficulty it creates to the philosopher in dis- 
 covering the first principles of the human 
 mind. 
 
 Tlie firm cohesion of the parts of a body, 
 is no more like that sensation by which I 
 perceive it to be hard, than the vibration of 
 a sonorous body is like the sound I hear : 
 nor can I possibly perceive, by my reason, 
 any connection between the one and the 
 other. No man can give a reason, why the 
 vibration of a body might not have given 
 the sensation of smelling, and the ef3uvia
 
 OF TOUCH. 
 
 121 
 
 of bodies affected our hearing, if it had so 
 pleased our Maker. In like manner, no 
 man can ^ive a reason whv the sensations 
 of smell, or taste, or sound, might not have 
 indicated hardness, as well as that sensa- 
 tion which, by our constitution, does indi- 
 cate it. Indeed, no man can conceive any 
 sensation to resemble any known quality of 
 bodies. Nor can any man shew, by any 
 good argument, that all our sensations 
 might not have been as they are, though no 
 body, nor quality of body, had ever existed. 
 
 Here, then, is a phoenomenon of human 
 nature, which comes to be resolved. Hard- 
 ness of bodies is a thing that we conceive 
 as distinctly, and believe as firmly, as any- 
 thing in nature. We have no way of com- 
 ing at this conception and belief, but by 
 means of a certain sensation of touch, to 
 which hardness hath not the least simili- 
 tude ; nor can we, by any rules of rea- 
 soning, infer the one from the other. The 
 question is. How we come by this conception 
 and belief ? 
 
 First, as to the conception : Shall we 
 call it an idea of sensation, or of retlectiou ? 
 The last will not be affirmed ; and as little 
 can the first, unless we will call that an 
 idea of sensation which hath no resem- 
 blance to any sensation. So that the 
 origin of this idea of hardness, one of the 
 most common and most distinct we have, 
 is not to be found in all our systems of the 
 mind : not even in those which have so 
 copiously endeavoured to deduce all our 
 notions from sensation and reflection. 
 
 But, secondly, supposing we have got the 
 conception of hardness, how come we by 
 the belief of it ? Is it self-evident, from 
 comparing the ideas, that such a sensation 
 could not be felt, unless such a quality of 
 bodies existed ? No. Can it be proved by 
 probable or certain arguments ? No ; it 
 cannot. Have we got this belief, then, by 
 tradition, liy education, or by experience ? 
 No ; it is not got in any of these ways. 
 Shall we then throw off this belief as hav- 
 ing no foundation in reason ? Alas ! it is 
 not in our power ; it triumphs over reason, 
 and laughs at all the arguments of a philoso- 
 pher. Even the author of the " Treatise 
 of Human Nature," though he saw no rea- 
 son for this belief, but many against it, could 
 hardly conquer it in his speculative and 
 solitary moments ; at other times, he fairly 
 yielded to it, and confesses that he found 
 himself under a necessity to do so. 
 
 What shall we say, then, of this concep- 
 tion, and this belief, which are so unac- 
 countable and untractable ? I see nothing 
 left, but to conclude, that, by an original 
 principle of our constitution, a certain sens- 
 ation of touch both suggests to the mind 
 the conception of hardness, and creates the 
 b«Jiof of it : or, in other words, that this sens- 
 
 ation is a natural sign of hardness. And 
 this I shall endeavour more fully to explain. 
 
 Section HI. 
 
 OP NATURAL SIGNS. 
 
 As in artificial signs there is often 
 neither similitude between the sign and 
 thi'ig signified, nor any connection that 
 arises necessarily from the nature of the 
 things, so it is also in natural signs. The 
 word gold has no similitude to the substance 
 signified by it ; nor is it in its own nature 
 more fit to signify this than any other sub- 
 stance ; yet, by habit and custom, it sug- 
 gests this and no other. In like manner, 
 a sensation of touch sugi^ests hardness, 
 although it hath neither similitude to hard- 
 ness, nor, as far as we can perceive, any 
 necessary connection with it. The differ- 
 ence betwixt these two signs lies only in 
 this — that, in the first, the suggestion is the 
 effect of habit and custom ; in the second, 
 it is not the effect of habit, but of the ori- 
 ginal constitution of our minds. 
 
 It appears evident from what hath been 
 said on the subject of language, that there 
 are natural signs as well as artificial ; and 
 particularly, that the thoughts, purposes, 
 and dispositions of the mind, have their 
 natural signs in the features of the face, the 
 modulation of the voice, and the motion 
 and attitude of the body : that, without a 
 natural knowledge of the connection between 
 these signs and the things signified by them, 
 language could never have been invented 
 and established among men : and, that the 
 fine arts are all founded upon this connec- 
 tion, which we may call tite nalitral language 
 cf mankind. It is now proper to observe, 
 that there are difterent orders of natural 
 signs, and to point out the different classes 
 into which tliey may be distinguished, that 
 we may more distinctly conceive the rela- 
 tion between our sensations and the things 
 they suggest, and what we mean by calling 
 sensations signs of external things. 
 
 The first class of natural signs compre- 
 hends those whose connection with the 
 thing signified is established by nature, but 
 discovered only by experience. The whole 
 of genuine philosophy consists in discover- 
 ing such connections, and reducing tiiem 
 to general rules. The great Lord Verulam 
 had a perfect comprehension of this, when 
 he called it un inlir/iretation of natitrr. No 
 man ever more distinctly understood or 
 happily expressed the nature and founda- 
 tion of the piiilosophic art. What is all we 
 know of mechanics, astronomy, and ojitics, 
 but connections established by nature, and 
 discovered by experience or observation, 
 and consequences deduced from them P
 
 122 
 
 OF THE HUMAN MIND. 
 
 All the knowledge we have in agriculture, 
 gardening, chemistry, and medicine, is built 
 upon the same foundation. And if ever 
 our philosophy concerning the human mind 
 is carried so far as to deserve the name of 
 science, which ought never to be despah-ed 
 of, it must be by observing facts, reducing 
 them to general rules, and drawing just con- 
 clusions from them. What we commonly 
 call natural causes might, with more pro- 
 priety, be called natural si,(/ns, and what we 
 call effects, the things signified. The causes 
 have no proper efficiency or casuality, as far 
 as we Icnow ; and all we can certainly affirm 
 is, that nature hath established a constant 
 conjunction between them and the things 
 called their effects ; and hath given to man- 
 kind a disposition to observe those con- 
 nections, to confide in their continuance, and 
 to make use of them for the improvement 
 of our knowledge, and increase of our power. 
 
 A second class is that wherein the con- 
 nection between the sign and thing signi- 
 fied, is not only established by nature, but 
 discovered to us by a natural principle, 
 without reasoning or experience. Of this 
 kind are the natural signs of human 
 thoughts, purposes, and desires, which 
 have been already mentioned as the natural 
 language of mankind. An infant may be 
 put into a fright by an angry coimtenance, 
 and soothed again by smiles and blandish- 
 ments. A child that has a good musical 
 ear, may be put to sleep or to dance, may be 
 made men-y or sorrowful, by the modula,- 
 tion of musical sounds. The principles of 
 all the fine arts, and of what we call a fine 
 taste, may be resolved into connections of 
 this kind. A fine taste may be improved 
 by reasoning and experience ; but if the 
 first principles of it were not planted in our 
 minds by nature, it could never be ac- 
 quired. Nay, we have already made it 
 appear, that a great part of this knowledge 
 %vhich we have by nature, is lost by tlie 
 disuse of natural signs, and the substitution 
 of artificial in their place. 
 
 A third class of natural signs compre- 
 hends those which, though we never before 
 had any notion or conception of the thing 
 signified, do suggest it, or conjure it up, 
 as it were, by a natural kind of magic, and 
 at once give us a conception and create a 
 belief of it. I shewed formerly, that our 
 sensations suggest to us a sentient being or 
 mind to which they belong — a being which 
 hath a permanent existence, although the 
 sensations are transient and of short dura- 
 tion — a being which is still the same, wiiile 
 its sensations and other operations are 
 varied ten thousand ways — a being which 
 hath the same relation to all that infinite 
 variety of thoughts, purposes, actions, 
 affections, enjoyments, and sufferings, which 
 we are conscious of, or can remember. The 
 
 conception of a mind is neither an idea of 
 sensation nor of reflection ; for it is neither 
 like any of our sensations, nor like any- 
 thing we are conscious of. The first con- 
 ception of it, as well as the belief of it, and 
 of the common relation it bears to all that we 
 are conscious of, or remember, is suggested to 
 every thinlung being, we do not know how. 
 
 The notion of hardness in bodies, as well 
 as the belief of it, are got in a similar 
 manner ; being, by an original principle of 
 our nature, annexed to that sensation 
 which we have when we feel a hard body. 
 And so naturally and necessarily does the 
 sensation convey the notion and belief of 
 liardness, that hitherto they have been 
 confounded by the most acute inquirers 
 into the principles of human nature, al- 
 though they appear, upon accurate reflec- 
 tion, not only to be difierent things, but as 
 unlike as pain is to the point of a sword. 
 
 It may be observed, that, as the first 
 class of natural signs I have mentioned is 
 the foundation of true philosophy, and the 
 second the foundation of the fine arts, or 
 of taste — so the last is the foundation of 
 common sense — a part of human nature 
 which hath never been explained.* 
 
 I take it for granted, that the notion of 
 hardness, and the belief of it, is first got 
 by means of that particular sensation 
 which, as far back as we can remember, 
 does invariably suggest it ; and that, if we 
 had never had such a feeling, we should 
 never have had any notion of hardness. 1 
 think it is evident, that we cannot, by 
 reasoning from our sensations, collect the 
 existence of bodies at all, far less any of 
 their qualities. This hath been proved by 
 unanswerable arguments by the Bishop of 
 Cloyne, and by the author of the " Treatise 
 of Human Nature." It appears as evi- 
 dent that this connection between our sens- 
 ations and the conception and behef of 
 external existences cannot be produced by 
 habit, experience, education, or any prin- 
 ciple of human nature that hath been 
 admitted by philosophers. At the same 
 time, it is a fact that such sensations are 
 invariably connected with the conception 
 and belief of external existences. Hence, 
 by all rules of just reasoning, we must con- 
 clude, that this connection is the effect of 
 our constitution, and ought to be considered 
 as an original principle of human nature, 
 till we find some more general principle 
 into which it may be resolved. + 
 
 » See Stewart's " Elements of the Philosophy 
 of the Human Mind." Vol. II., chap, i., \ 3, last 
 note.— H. 
 
 t This whole doctrine of natural signs, on which his 
 philosophy is in a great measure established, was bor- 
 rowed l)y Reid, in principle, and even in expression, 
 from Berkelev. Compare " Minute Philosopher, ' 
 Dial IV., y 7, 1 1, 12 ; " New Theory of Vision." 
 §§ 144, 147; "Theory of Vision Vindicated," 8§ 38 
 — 43-H.
 
 OF TOUCH. 
 
 123 
 
 Section IF. 
 
 or HARDNESS, AND OTHKa PRIMARY 
 QUALITIES. 
 
 Further, I observe that hardness is a 
 quaUty, of which we have as clear and 
 distinct a conception as of anything what- 
 soever. The cohesion of the parts of a 
 body with more or less force, is perfectly 
 understood, though its cause is not ; we 
 know what it is, as well as how it affects 
 the touch. It is, therefore, a quality of a 
 quite different order from those secondary 
 qualities we have already taken notice of, 
 whereof we know no more naturally than 
 that they are adapted to raise certain sens- 
 ations in us. If hardness were a quality 
 of the same kind, it would be a proper in- 
 quiry for philosophers, what hardness in 
 bodies is ? and we should have had various 
 hypotheses about it, as well as about co- 
 lour and heat. But it is evident that any 
 such hypothesis would be ridiculous. If 
 any man should say, that hardness in bo- 
 dies is a certain vibration of their parts, or 
 that it is certain effluvia emitted by them 
 which affect our touch in the manner we 
 feel — such hypotheses would shock com- 
 mon sense ; because we all know that, if 
 the parts of a body adhere strongly, it is 
 hard, although it should neither emit efflu- 
 via nor vibrate. Yet, at the same time, 
 no man can say, but that effluvia, or the 
 vibration of the parts of a body, might 
 have affected our touch, in the same man- 
 ner that hardness now does, if it had so 
 pleased the Author of our nature ; and, if 
 either of these hypotheses is applied to ex- 
 plam a secondary quality — such as smell, 
 or taste, or sound, or colour, or heat — there 
 appears no manifest absurdity in the sup- 
 position. 
 
 The distinction betwixt primary and se- 
 condary qualities hath had several revolu- 
 tions. Democritus and Epicurus, and their 
 followers, maintained it. Aristotle and the 
 Peripatetics abolished it. Des Cartes, 
 Malebranche, and Locke, revived it, and 
 were thought to have put it in a very clear 
 light. But Bishop Berkeley again dis- 
 carded this distinction, by such proofs as 
 must be convincing to those that hold 
 the received doctrine of ideas.* Yet, 
 after all, there appears to be a real found- 
 ation for it in the principles of our na- 
 ture. 
 
 What hath been said of hardness, is so 
 easily ajjplicable, not only to its opposite, 
 Boftne.ss, but likewise to roughness and 
 
 • On thiB distinction of Pr/mary and Secondary 
 Oualitimi, «ee " Eisayson the liitcllectual I'owers," 
 K»«ay H., chnp 17, and Note I), at the end of 
 the vohime. — H. 
 
 smoothness, to figure and motion, that we 
 may be excused from making the applica- 
 tion, which would only be a repetition of 
 what hath been said. All these, by means 
 of certain corresponding sensations of touch, 
 are presented to the mind as real external 
 qualities ; the conception and the belief of 
 them are invariably connected with the 
 corresponding sensations, by an original 
 principle of human nature. Their sensa- 
 tions have no name in any language ; they 
 have not only been overlooked by the vul- 
 gar, but by philosophers ; or, if they have 
 been at all taken notice of, they have been 
 confounded with the external qualities which 
 they suggest. 
 
 Section V. 
 
 OF EXTENSION. 
 
 It is further to be observed, that hard- 
 ness and softness, roughness and smooth- 
 ness, figure and motion, do all suppose ex- 
 tension, and cannot be conceived without 
 it ; yet, I think it must, on the other hand, 
 be allowed that, if we had never felt any 
 tiling hard or soft, rough or smooth, figured 
 or moved, we should never have had a con- 
 ception of extension ;" so that, as there is 
 good ground to believe that the notion of 
 extension could not be prior to that of other 
 primary qualities, so it is certain that it 
 could not be posterior to the notion of any 
 of them, being necessarily implied in them 
 all.f 
 
 Extension, therefore, seems to be a qua- 
 lity suggested to us, by the very same sens- 
 ations which suggest the other qualities 
 above mentioned. When I grasp a ball in 
 my hand, I perceive it at once hard, 
 figured, and extended. The feeling is very 
 simple, and hath not the least resemblance 
 to any quality of body. Yet it suggests to 
 us three primary qualities perfectly dis- 
 tinct from one another, as well as from the 
 sensation which indicates them. When 
 I move my hand along the table, the feel- 
 ing is so simple that I find it difficult to 
 distinguish it into things of dift'erent na- 
 tures ; yet, it inmiediatey suggests hardness, 
 smoothness, extension, and motion — things 
 
 * According to lU'id, Extei sion 'Space) is a no. 
 tion It poiteri'iri, ttie result of experience. Acconl- 
 ing to Kant, it is a priori ; cxpcrionic imly afTording 
 the occasions required by the mind to exert the acts, 
 of which theiiituition ol space is a condition. To<he 
 former it is thus a conli7if:cnl : to the latter, a nfcw- 
 sari/ mental possession— II. 
 
 f In this paragraph, to say nothing of others in 
 the " Incpiiry," Kcid cvidenlly excludes ii/jA/ as a 
 sense, through which the notion itl extension or space, 
 enters into the mind. In his later work, the " Ks- 
 says on the Intellectual I'owers,'' he, however, ■ex- 
 pressly allows that liinctlon toiig/it nnd touch, and 
 lo those senses alone See (^ssay II., chap, 19, p. 
 ■M'i, quarto edi ion. — It.
 
 124 
 
 OF THE HUMAN MIND. 
 
 of very different natures, and all of tliera 
 as distinctly understood as the feeling which 
 suggests them. 
 
 We are commonly told by philosophers, 
 that we get the idea of extension by feeling 
 along the extremities of a body, as if there 
 was no manner of difficulty in the matter. 
 I have sought, with great pains, I confess, 
 to find out how this idea can be got by feel- 
 ing ; but I have sought in vain. Yet it is 
 one of the clearest and most distinct notions 
 we have ; nor is there anything whatsoever 
 about which the human understanding can 
 carry on so many long and demonstrative 
 trains of reasoning.* 
 
 The notion of extension is so familiar 
 to us from infancy, and so constantly ob- 
 truded by everything we see and feel, that 
 we are apt to think it obvious how it comes 
 into the mind ; but upon a narrower ex- 
 amination we shall find it utterly inexpli- 
 cable. It is true we have feelings of touch, 
 which every moment present extension 
 to the mind ; but how they come to do 
 80, is the question ; for those feelings do 
 no more resemble extension, than they re- 
 semble justice or courage — nor can the 
 existence of extended things be inferred 
 from those feelings by any rules of reason- 
 ing ; so that the feelings we have by touch, 
 can neither explain how we get the notion, 
 nor how we come by the belief of extended 
 things. 
 
 What hath imposed upon philosophers 
 in this matter is, that the feelings of touch, 
 which suggest primary qualities, have no 
 names, nor are they ever reflected upon. 
 They pass through the mind instantane- 
 ously, and serve only to introduce the no- 
 tion and belief of external things, which, 
 by our constitution, are connected with 
 them. They are natural signs, and the 
 mind immediately passes to the thing sig- 
 nified, without making the least reflection 
 upon the sign, or observing that there was 
 any such thii)g. Hence it hath always been 
 taken for granted, that the ideas of exten- 
 sion, figure, and motion, are ideas of sensa- 
 tion, which enter into the mind by the sense 
 of touch, in the same manner as the sensa- 
 tions of sound and smell do by the ear and 
 nose.-j- The sensations of touch are so con- 
 
 * All the attempts that have^ subsequently to 
 Rei'i, been made, to analyse the notion of Space into 
 the expinence ot sense, have failed, equally as those 
 before him.— H. 
 
 t It has not " always been taken for granted, that the 
 ideas o( Extension, Figure, and Motion, are ideas of 
 seination." Even a distinguished predecessor of Keid, 
 in his Chair at Glasgow, denied this doctrine of the 
 fensual school, to which he generally adhered. I would 
 not be Bupposeid to suspect Keid of the slightest disin. 
 genuousness, but hehas certainly here and elsewhere 
 been anticipated by Hutcheaon, in some of the most 
 important principles, no less than in some of the 
 weaker positions of his philosophy. I-quole, without 
 retrenchment, the following note from Hutcheson's 
 '• Euay on the Passions," though only part of it is 
 
 nected, by our constitution, with the notions 
 of extension, figure, and motion, that phi- 
 losophers have mistaken the one for the 
 
 strictly relative to the assertion in the text : — " It is 
 not easy to divide distinctly our several scnsa ions 
 into cla-ses I'hedivision ol'our External Senses into 
 the five common classes, seems very imperfect Some 
 sensations, received without any previous idea, can 
 cither be reduced to none of them — such as th« sens- 
 ations of Hunger, Thirst, Weariness, Sickness; or 
 it we reduce -thim to the sense of Feeling, they are 
 perceptions as ditFere.it irom the other ideas of Touch 
 — such as Cold, Heat, Hardness, Softness — as the ideas 
 ot taste or smell. Others have hinted at an external 
 sense, diftcreiit from all of these." [This allusion has 
 jiuzzled (jur Scottish p-ychologists. Hutcheson evi- 
 dently refers to the sixth sense, or sense of venereal tit. 
 illation, proposed by tht elder Scaliger, and approved 
 of by Bacon, 15uffon, Vultaire, ^c.j •' The following 
 general account may possibly be useful. (1 °} — That 
 certain motions raised in our bodies are, by a general 
 law, constituted the cccasi' n of perceptions in the 
 mind, (ii") These perceptions never come entirely 
 alone, but have some otiier perception joined with 
 them. Thus every sensation is accompanied with 
 the idea of Duration, and yet duration is not a. sens, 
 ible idea, since it also accompanies ideas of inter, 
 nal consciousness or rejii-ction : so the idea of 
 Number may accompany any sensible ideas, and yet 
 may also accompany any other ideas, as well asexler. 
 nal sensations. Brutes, when several objects are 
 before them, have probably all the propi r ideas of 
 sight which we have, without the idea of number. 
 (3") .^'ome ideas are found accomnanying the most 
 difterent sensations, which yet are not to be perceived 
 s.paratciy from some.sensilile quality. Such are Ex. 
 tension. Figure, Motion, and Hest, which accompany 
 the ide'.is ot Sight or Colours, and yet may be per, 
 ceived without them, asm the ideas ot Touch, at lea.t 
 if we move our organs along the parts of tlie body 
 touched. Extension, Figure, Motion, or licit, seem 
 therefore to be more properly called ideas accom. 
 panyrngtlie sensations of tUgJit and Touch, than the 
 sensations of either of these senses ; siine ihey 
 can be received sometimes withuiu the ideas of 
 Colour, and sometimes without those ot 'I'ouching, 
 though never wiihout the one or the other 'J he 
 pe,-cept:ons uhich ure purely sensible, received each 
 by its proper sense, are l astes. Smells, C olours, 
 Sound, Cold, Heat, ^c. "Yhnunivet sal concomitant 
 ideas which may attend any idea whatsoever, are 
 Duration and Number. The ideas which accompany 
 the most different sensations, are Extension, Figure, 
 Motion, and Kest. These all arise wiihuut at.ypre. 
 vious ideas assembled or compared— the concvmitant 
 ideas are reputed images of something ex ernal "— 
 >ect 1 , Art. 1. The reader may likewise consult the 
 same author's " Synopsis Metaphysicae," Part, II., 
 cap. 1,^3 
 
 But here I may observe, in the first place, that the 
 statement made in the preceding quotation, (and still 
 iiiOre articulately in the " Synopsis,") that Duration 
 or Time is the inseparable concomitant both of sense 
 and reflection, had been also made by Aristotle and 
 many other philosophers; and it is indeed curious 
 how I'lng philosophers were on the vtrge of enuiu 
 ciating the great doctrine first proclaimed by Kant 
 — that 'lime is a fuiulamen'al condiiioii, form, or 
 category ol thought. In the second place, I may no. 
 lice that Hutcheson is not entitled to the praise 
 accorded him by Stewart and KoyerCollardforhisori. 
 ginality in " Ihefiiie and important observation that 
 Extension, Figure, Motion, and Rest, are rather 
 ideas accompanying the perceptions ot touch and 
 vision, than perciptions ol these senses, properly so 
 called." In this, he seems only lohave, with others, 
 repeated Aristotle, who, in his treatise on the 
 Soul. (-Book II., Ch. 6, Text (U, and Book III. Ch. 
 I, Text 13."),) calls Motion and Rest, iianiiitude, {Ex- 
 tension,) Figure, and Number, (Hutcheson's very 
 list,) the common concomitants {ocxeJ^evdiyra. xai 
 Konic) of sight and touch, and expressly denies 
 Itiera to be impressions of sense — the sense having 
 no passive affection from these qualities. To these 
 five common ccmcomitants, some of the schoolmen 
 added also, (but out of Aristotle,) Place, Distance, 
 Poiitiun, and Co7itinuitj/. — H.
 
 OF TOUCH. 
 
 125 
 
 other, and never have been able to discern 
 that they were not only distinct things, but 
 uhogether unlike. However, if we will 
 reason distinctly upon this subject, we ought 
 to give names to those feelings of touch ; 
 we must accustom ourselves to attend to 
 them, and to reflect upon them, that we 
 may be able to disjoin them from, and to 
 compare them with, the qualities signified 
 or suggested by them. 
 
 The habit of doing this is not to be at- 
 tained without pains and practice ; and till 
 a man hath acquired this habit, it will be 
 impossible for him to think distinctly, or to 
 judge right, upon this subject. 
 
 Let a man press his hand against the 
 table — /le feels it hard. But what is the mean- 
 ing of this? — The meaning undoubtedly 
 is, that he hath a certain feeling of touch, 
 from which he concludes, without any rea- 
 soning, or comparing ideas, that there is 
 something external really existing, whose 
 parts stick so firmly together, that they can- 
 not be displaced without considerable force. 
 
 There is here a feeling, and a conclu- 
 sion drawn from it, or some way suggested 
 by it. In order to compare these, we 
 must view them separately, and then con- 
 sider by what tie they are connected, and 
 wlierein they resemble one another. The 
 hardness of the table is the conclusion, the 
 feeling is the medium by which we are led 
 ti) that conclusion. Let a man attend dis- 
 tinctly to this medium, and to the conclu- 
 sion, and he will perceive them to be as 
 unhke as any two things in nature. The 
 one is a sensation of- the mind, which can 
 Iiave no existence but in a sentient being ; 
 nor can it exist one moment longer than it 
 is felt ; tiie other is in the table, and we 
 conclude, without any difficulty, that it was 
 in the table before it was felt, and continues 
 after the feeling is over. The one implies 
 no kind of extension, nor parts, nor cohe- 
 sion ; the other implies all these. Both, 
 indeed, admit of degrees, and the feeling, 
 beyond a certain degree, is a species of 
 pain ; but adamantine hardness does not 
 imply the least pain. 
 
 And as tlie feeling hath no similitude to 
 hardness, so neither can our reason per- 
 ceive the least tie or connection between 
 them ; nor will the logician ever be able to 
 shew a reason why we should conclude 
 hardness from this feeling, rather than soft- 
 ness, or any other quality whatsoever. But, 
 in reality, all mankind are led by their con- 
 stitution to conclude hardness from this 
 feeling. 
 
 The sensation of heat, and the sensation 
 we have by pressing a hard body, arc equally 
 feelings ; nor can wc, by reasoning, draw 
 any conclusion from tlic one but wjiat may 
 be drawn from tlie other : but, by nur con- 
 btitution, we conclude from tlie first an ob- 
 
 scure or occult quality, of which we have 
 only this relative conception, that it is 
 something adapted to raise in us the sensa- 
 tion of heat ; from the second, we conclude 
 a quality of which we have a clear and dis- 
 tinct conception — to wit, the hardness-of the 
 body. 
 
 Section VI. 
 
 OF EXTENSION. 
 
 To put this matter in another light, it 
 may be proper to try, whether from sensa- 
 tion alone we can collect any notion of ex- 
 tension, figure, motion, and space.* I take 
 it for granted, that a blind man hath the 
 same notions of extension, figure, and mo- 
 tion, as a man that sees ; that Dr Saunder- 
 son had the same notion of a cone, a cylin- 
 der, and a sphere, and of the motions and 
 distances of the heavenly bodies, as Sir Isaac 
 Newton. -f- 
 
 As sight, therefore, is not necessary for 
 our acquiring those notions, we shall leave 
 it out altogether in our inquiry into the 
 first origin of them ; and shall suppose a 
 blind man, by some strange distemper, to 
 have lost all the experience, and habits, 
 and notions he had got by touch ; not to 
 have the least conception of the existence, 
 figure, dimensions, or extension, either of 
 his own body, or of any other ; but to have 
 all his knowledge of external things to ac- 
 quire anew, by meajis of sensation, and the 
 power of reason, which we suppose to re- 
 main entire. 
 
 We shall, first, suppose his body fixed 
 immovably in one place, and that he can 
 only have the feelings of touch, by the 
 application of other bodies to it. Suppose 
 him first to be pricked with a pin — this 
 will, no doubt, give a smart sensation : he 
 feels pain ; but what can he irifer from it ? 
 Nothing, surely, with regard to the existence 
 or figure of a pin. He can infer nothing 
 from this species of pain, which he may not 
 as well infer from the gout or sciatica. 
 Conmion sense may lead him to thiidi that 
 this pain has a cause ; but whether this 
 cause is boily or spirit, extended or unex- 
 teuded, figured or not figured, he cannot 
 possibly, from any principles he is supposed 
 to have, form the least conjecture. Hav- 
 ing had fonnerly no notion of body or of 
 extension, the prick of a {)in can give him 
 none. 
 
 Suppose, next, a body not ]ioin tcd, but 
 
 » Why are /i'jrVcntionliiul S/xj r ili.stiiif;iiii.he(l u» 
 co-orilinatc, and tlms oddly siiudiMrd ?— H. 
 
 f I he (iliRcrvatKiMs of I'lamir, on a. person horn 
 blind, woidd pnivc, however, that ji|'/(/, not I itch, is 
 111!' sense liv which we iiriniijially oiiiniii niir knnw- 
 ledtju of I'igure, and our ititpii iciil knowlrdnf of 
 Space. Saiindcr»oii,at any raio, was not born blind, 
 — H.
 
 126 
 
 OF THE HUMAN MIND. 
 
 blunt, is applied to his body with a force 
 gradually iucreased until it bruises him. 
 What has he got by this, but another sens- 
 ation or train of sensations, from which 
 he is able to conclude as little as from the 
 former ? A scirrhous tumour in any in- 
 ward part of the body, by pressing upon 
 the adjacent parts, may give the same kind 
 of sensation as the pressure of an external 
 body, without conveying any notion but 
 tliat of pain, which, surely, hath no resem- 
 blance to extension. 
 
 Suppose, thirdly, that the body applied 
 to him touches a larger or a lesser part of 
 his body. Can this give him any notion 
 of its extension or dimensions ? To me it 
 seems impossible that it should, unless he 
 had some previous notion of the dimen- 
 sions and figure of his own body, to serve 
 him as a measure.* When ray two hands 
 touch the extremities of a body, if I know 
 them to be a foot asunder, I easily col- 
 lect that the body is a foot long ; and, if I 
 know them to be five feet asunder, that it 
 is five feet long ; but, if I know not what 
 the distance of my hands is, I cannot know 
 the length of the object they grasp ; and, 
 if I have no previous notion of hands at 
 all, or of distance between them, I can 
 never get that notion by their being touched. 
 
 Suppose, again, that a body is drawn 
 along his hands or face, while they are at 
 rest. Can this give him any notion of 
 space or motion ? It no doubt gives a new 
 feeling ; but how it should convey a notion 
 of space or motion to one who had none 
 before, I cannot conceive. The blood moves 
 along the arteries and veins, and this motion, 
 when violent, is felt : but I imagine no man, 
 by this feeling, could get the conception of 
 space or motion, if he had it not before. 
 Such a motion may give a certain succes- 
 sion of feelings, as the colic may do ; but no 
 feelings, nor any combination of feelings, 
 can ever resemble space or motion. 
 
 Let us next suppose, that he makes some 
 instinctive effort to move his head or his 
 hand ; but that no motion follows, either 
 on account of external resistance, or of 
 palsy. Can this effort convey the notion 
 of space and motion to one who never had it 
 before ? Surely it cannot. 
 
 Last of all, let us suppose that he moves 
 a limb by instinct, without having had any 
 previous notion of space or motion. He 
 has here a new sensation, which accom- 
 panies the flexure of joints, and the swelling 
 of muscles. But how this sensation can 
 convey into his mind the idea of space and 
 motion, is still altogether mysterious and 
 unintelligible. The motions of the heart 
 
 ♦ Nay, the recent observations of Weber estaiilish 
 the curious fact, that the same extent will not appear 
 the tame to the touch at different parts of the body. 
 
 and lungs are all performed by the con- 
 traction of muscles, yet give no conception 
 of space or motion. An embryo in the 
 womb has many such motions, and probably 
 the feelings that accompany them, without 
 any idea of space or motion. 
 
 Upon the whole, it appears that our 
 phiiosophers have imposed upon themselves 
 and upon us, in pretending to deduce from 
 sensation the first origin of our notions of 
 external existences, of space, motion, and 
 extension,* and all the primary qualities of 
 body — that is, the qualities whereof we 
 have the most clear and distinct conception. 
 These qualities do not at all tally with any 
 system of the human faculties that hath 
 been advanced. They have no resemblance 
 to any sensation, or to any operation of our 
 minds ; and, therefore, they cannot be 
 ideas either of sensation or of reflection. 
 The very conception of them is irreconcil- 
 able to the principles of all our philosophic 
 systems of the understanding. The belief 
 of them is no less so. 
 
 Section VII. 
 
 OF THE EXISTENCE OF A MATERIAL WORLD. 
 
 It is beyond our power to say when, or 
 in what order, we came by our notions of 
 these qualities. When we trace the opera- 
 tions of our minds as far back as memory 
 and reflection can carry us, we find them 
 already in possession of our imagination and 
 belief, and quite familiar to the mind : but 
 how they came first into its acquaintance, 
 or what has given them so strong a hold of 
 our belief, and what regard they deserve, 
 are, no doubt, very important questions in 
 the philosophy of human nature. 
 
 Shall we, with the Bishop of Cloyne, 
 serve them with a quo warranto, and have 
 them tried at the bar of philosophy, upon 
 the statute of the ideal system ? Indeed, 
 in this trial they seem to have come off 
 very pitifully ; for, although they had very 
 able counsel, learned in the law — viz., Des 
 Cartes, Malebranche, and Locke, who said 
 everything they could for their clients — the 
 
 * That the notion of Space is a necessary condition 
 of 1 bought, and that, as such, it is impossible tn de- 
 rive it from experience, has been cogently demon- 
 strated by Kant. But that we may not, through 
 sense, have empirically an immediate perception of 
 something extcnied, I have yet seen no vahd reason 
 to doubt. VYtc'a priori Conception does not exclude 
 the.« posto'iori Perception ; and this latter cannot be 
 rejected without belying the evidence olconscioiisnrss, 
 which assures us that we are immediately cognizant, 
 not only of a Self but of a Not-Se'f, not only of ?»ind 
 but o{ matter : and matter cannot lie inmediately 
 known — that is, k-nown as-exi^tiig— except-as '^ome- 
 thing extended. In this, however, I venture a step 
 beyond Reidand Stewart, no loss than beyond Kant ; 
 though I am convinced that the piiilosophy of the 
 two former tended to-'his conclusion, which is, in 
 fact, that ol the common gense ol mankind. — H.
 
 OF TOUCH. 
 
 127 
 
 Bishop of Cloyne, believing them to be 
 aiders and abetters of heresj' and schism, 
 prosecuted them with great vigour, full}' 
 answered all that had been pleaded in their 
 defence, and silenced their ablest advocates, 
 who seem, for half a century past, to decline 
 the argument, and to trust to the favour of 
 the jury rather than to the strength of 
 their pleadings. 
 
 Thus, the wisdom oi philosophy is set in 
 opposition to the common sense of mankind. 
 The first pretends to demonstrate, a piioi i, 
 that there can be no such thing as a mate- 
 rial world ; that sun, moon, stars, and earth, 
 vegetable and animal bodies, are, and can 
 be nothing else, but sensations m the mind, 
 or images of those sensations in the memory 
 and imagination ; that, like pain and joy, 
 they can have no existence when they are 
 not thought of. The last can conceive no 
 otherwise of this opinion, than as a kind of 
 metaphysical lunacy, and concludes that too 
 much learning is apt to make men mad ; 
 and that the man \vho seriously entertains 
 this belief, though in other respects he may be 
 a very good man, as a man may be who be- 
 lieves that he is made of glass ; yet, surely 
 he hath a soft place in his understanding, 
 and hath been hurt by much thinking. 
 
 This opposition betwixt philosophy and 
 common sense, is apt to have a very un- 
 happy influence upon the philosopher him- 
 self. He sees human nature in an odd, 
 unamiable, and mortifying light. He con- 
 siders himself, and the rest of his species, 
 as born under a necessity of believing ten 
 thousand absurdities and contradictions, 
 and endowed with such a pittance of reason 
 as is just sufficient to make this unhapjjy 
 discovery : and this is all the fruit of his 
 profound speculations. Such notions of 
 human nature tend to slacken every nerve of 
 the soul, to put every noble purpose and sen- 
 timent out of countenance, and spread a me- 
 lancholy gloom over the whole face of things. 
 
 If this is wisdom, let me be deluded witli 
 the vulgar. I find something within me 
 that recoils against it, and insjiires more 
 reverent sentiments of the human kind, and 
 of the universal administration. Common 
 Sense and Reason* have both one autlior; 
 that Almighty Author in all wliose other 
 works we observe a consistency, uniformity, 
 and beauty which charm and delight tlie 
 understanding : there must, therefore, be 
 some order and consistency in the human 
 faculties, as well as in other parts of his 
 workmanship. A man that thinks rever- 
 ently of his own kind, and esteems true 
 wisdom and pliilosoi)liy, will not be fond, 
 nay, will be vury suspicious, of such stranL;<! 
 
 • 'Die reader will again notire lhi« and the rtlior 
 In-tanccs whirh follow, of the iiiiicciK.'icy ol Hfid'n 
 laiiKuaKc in hi« catlifr woik, ((m-titiiting, as diflir. 
 eiit, Heaion and Cummon Srnic. — H. 
 
 and paradoxical opinions. If they are false, 
 they disgrace philosophy ; and, if they are 
 true, they degrade the human species, and 
 make us justly ashamed of our frame. 
 
 To what purpose is it for philosophy to 
 decide against common sense in this or any 
 other matter ? The belief of a material 
 world is older, and of more authority, than 
 any principles of philosophy. It declines the 
 tribunal of reason,* and laughs at all the 
 artillery of the logician. It retains its 
 sovereign authority in spite of all the edicts 
 of philosophy, and reason itself must stoop 
 to its orders. Even those philosophers who 
 have disowned the authority of our notions 
 of an external material world, confess that 
 they find themselves under a necessity of 
 submitting to their power. 
 
 Methinks, therefore, it were better to 
 make a virtue of necessity ; and, since we 
 cannot get rid of the vulgar notion and be- 
 lief of an external world, to reconcile our 
 reason to it as well as we can ; for, if Rea- 
 son* should stomach and fret ever so much 
 at this yoke, she cannot throw it oft"; if she 
 will not be the servant of Common Sense, 
 she must be her slave. 
 
 In order, therefore, to reconcile Reason 
 to Common Sense* in this matter, I beg 
 leave to offer to the consideration of philo- 
 sophers these two observations. First, 
 That, in all this debate about the existence 
 of a material world, it hath been taken for 
 granted on both sides, that this same 
 material world, if any such there be, must 
 be the express image of our sensations ; 
 that we can have no conception of any 
 material thing which is not like some sens- 
 ation in our minds ; and particularly that 
 the sensations of touch are images of exten- 
 sion, hardness, figure, and motion. Every 
 argument brought against the existence of 
 a material world, either by the Bishop of 
 Cloyne, or by the author of the " Treatise 
 of Human Nature," supposeth this. If 
 this is true, their arguments are conclusive 
 and unanswerable ; but, on the other hand, 
 if it is not true, there is no sha<low of argu- 
 ment left. Have those philosophers, then, 
 given any solid proof of this hypothesis, 
 upon which the whole weight of so strange. 
 a system rests. No. Tliey have not so 
 much as attempted to do it. But, because 
 ancient and modern philosophers have 
 agreed in this opinion, they have taken it 
 for granted. l$ut let us, as beconios 
 philosophers, lay aside authority ; we 
 need not, surely, consult Aristotle or 
 Locke, to know whether pain be like 
 the point of a sword. I have as clear a 
 conception of extension, hardness, and 
 motion, as I have of the imint of a sword ; 
 and, with some pains and practice, I c;in 
 form as clear a notion of the other sensii- 
 * Si'C lait note. — H.
 
 I28 
 
 OF THE HUMAN MIND, 
 
 tions of touch as I have of pain. When I 
 do so, and compare them together, it ap- 
 pears to me clear as daylight, that the for- 
 mer are not of kin to the latter, nor resemble 
 them in any one feature. They are as 
 unlike, yea as certainly and manifestly un- 
 like, as pain is to the point of a sword. It 
 may be true, that those sensations first 
 introduced the material world to our ac- 
 quaintance; it may be true, that it seldom 
 or never appears without their company ; 
 but, for all that, they are as unlike as the 
 passion of anger is to those features of the 
 countenance which attend it. 
 
 So that, in the sentence those philoso- 
 phers have passed against the material 
 world, there is an ermr psrsonce. Their 
 proof touches not matter, or any of its qua- 
 lities ; but strikes directly against an idol 
 of their own imagination, a material world 
 made of ideas and sensations, which never 
 had, nor can have an existence. 
 
 Secondly, The very existence of our con- 
 ceptions of extension, figure, and motion, 
 since they are neither ideas of sensation nor 
 reflection, overturns the whole ideal system, 
 by which the material world hath been tried 
 and condemned ;* so that there hath been 
 likewise in this sentence an error juris. 
 
 It is a very fine and a just observation of 
 Locke, that, as no human art can create a 
 single particle of matter, and the whole ex- 
 tent of our power over the material world 
 consists in compounding, combining, and 
 disjoining the matter made to our hands ; 
 so, in the world of thought, the materials 
 are all made by nature, and can only be 
 variously combined and disjoined by us- 
 So that it is impossible for reason or preju- 
 dice, true or false philosophy, to produce 
 one simple notion or conception, which is 
 not the work of nature, and the result of 
 our constitution. The conception of exten- 
 sion, motion, and the other attributes of 
 matter, cannot be the effect of error or pre- 
 judice ; it must be the work of nature. 
 And the power or faculty by which we 
 acquire those concejitions, must be some- 
 thirig different from any power of the hu- 
 man mind that hath been explained, since 
 it is neither sensation nor reflection. 
 
 This I would, therefore, humbly propose, 
 as an expcrimcntum crucis, by which the 
 ideal system must stand or fall ; and it 
 brings the matter to a short issue : Exten- 
 sion, figure, motion, may, any one, or all 
 of them, be talcen for the subject of this 
 experiment. Either they are ideas of sens- 
 
 * It only overturns that Idealism founded on the 
 clumsy hypothesis of ideas lieing something different, 
 both from ihe reality they represent, and from the 
 mind contemplating their representation, and which, 
 also, derives all such ideas from without. This doc- 
 trine may.subven the ideahsm of Rerkeley, but it 
 even supplies a basis for an Idealism like that of 
 Fichte. See the following note. — H. 
 
 ation, or they are not. If any one of 
 them can be shewn to be an idea of sensa- 
 tion, or to have the least resemblance to 
 any sensation, I lay my hand upon my 
 mouth, and give up all pretence to recon- 
 cile reason to common sense in this matter, 
 and must suffer the ideal scepticism to 
 triumph. But if, on the other hand, they 
 are not ideas of sensation, nor like to any 
 sensation, then the ideal system is a rope 
 of sand, and all the laboured arguments of 
 the sceptical philosophy against a material 
 world, and against the existence of every 
 thing but impressions and ideas, proceed 
 upon a false hypothesis.* 
 
 • Nothing is easier th.in to shew, that, so f,ir fram 
 refuting Idealism, this doctrine affords it the best of 
 all possible foundations. If Idealism, indeed, supposed 
 the existence of ideas as tertia quiedavi, distinct at 
 once from the material object and the immaterial 
 subject, these intermediate entities being likewise 
 held to originate immediately or mediately in sense— 
 if this hypothesis, I say, were reqiii-ite.to Idealism, 
 then would Keid's criticism ofthat'doctri tie be a com. 
 plete and final confutation. But as this criticism 
 did not contemplate, so it does not confute that sim. 
 pier and more refined Idealism, which views.in ideas 
 only modifications of the mind itself; and which, in 
 jilace i^f sensualizing intellect, int'jilectualizes sense. 
 t)n the contrary, Keid, (and herein he is followed by 
 Mr Stewart,) in the doctrine now maintained, asserts 
 the very positions on which this scheme of Idealism 
 establishes its -conclusions. An P'goistical Idealism is 
 established, on the doctrine, that all our knowledge 
 is merely sui jeclive, or of the mind itself; that the 
 Ego has no immediate cognizance of a Non-Ego as 
 exl^tl^g, but that the Non-Eijo t* only represented to 
 us in a modification of the self-conscious Ego. This 
 doctrine being admitted, the Idealist has only to shew 
 that the supposition of a Non-Ego, or external world 
 really existent, is a groundless and unnecessary 
 assumption ; for, while the law of parciinony pro- 
 hibits the multiplication of substances or causes be. 
 yond what the plia^nomena require, ue have mani. 
 festly no rijjht to postulate for the Non.Eg ■ the dig- 
 nity of an independent substance beyond the Ego, 
 seeing that this Non-lgo is, ex hypolheai, known to 
 us, consequently exists for us, only as a phenomenon 
 of the Ego. — Now, the doctrine of our Scottish philo. 
 sophers is, in 'act, the very groundwork on which 
 the Egoistical Idealism reposes. That doctrine not 
 only maintains our sensations of the secondary qua. 
 lities to be the mere effects of certain unknown 
 causes, of which we are consequently entitled to 
 affirm nothing, butthat wehaveiiodirect and imme- 
 diate perception of extension and the olher'iirimary 
 qualities of matter. To limit ourselves to extension, 
 (or space,) vih\ch figure and motion (the two other 
 qualities proposed by Reid fur the experiraunt) sup. 
 pose, it is evident that if extension be not immediately 
 perceived as externally existing, exleitaed objects 
 cannot be immediately perceived as realities out, 
 and independent, of the percipient subject ; for, il we 
 were capable of such a perception ot such objects, we 
 should iiecessarilybe also capable of a perception of 
 this, the one essential attribute of their existence. 
 But, on the doctrine <■ t our Scott-sh philosophers. 
 Extension is a notion .suggested on occasion of sens, 
 ations supposed to bedetermined by certain unknown 
 causes ; which unknown causes are again supposed 
 lo be existences independent of the mind, and ex. 
 tended— their complement, in fact, constituting the 
 external world. All our knowledge of the Non.Ego 
 is thus merely ideal and mediate; we have no 
 knowledge of any really objective reality, except 
 thruugli a subjective representation or notion ; in 
 other words, we ate only immediat. ly cognizant of 
 certain modes of our own minds, and, in and through 
 them, mediately warned of the phaennmena of the 
 material universe. In :.ll essential respects, this doc. 
 trine of Keid and Stewart is. identical with Kant's; 
 except that the German philosopher, in holding space
 
 OF TOUCH. 
 
 12U 
 
 If our philosophy concernuig the mind 
 be so lame with regard to the origin of our 
 notions of the clearest, most simple, and 
 most familiar objects of thought, and the 
 powers from which they are derived, can 
 we expect that it should be more perfect in 
 the account it gives of the origin of our 
 opinions and belief ? We have seen already 
 some instances of its imperfection in this 
 respect : and, perhaps, that same nature 
 which hath given us the power to conceive 
 things altogether unlike to any of our sens- 
 ations, or to any operation of our minds, 
 hath likewise provided for our belief of 
 them, by some part of our constitution 
 hitherto not explained. 
 
 Bisliop Berkeley hath proved, beyond 
 the possibility of reply, that we cannot by 
 reasoning infer the existence of matter from 
 our sensations ; and tl)e author of the 
 " Treatise of Human Nature" hath proved 
 no less clearly, that we cannot by reasoning 
 inter the existence of our own or other 
 minds from our sensations. But are we to 
 admit nothing but what can be proved by 
 reasoning ? TJien we nmst be sceptics in- 
 deed, and believe nothing at all. The 
 author of the " Treatise of Human Na- 
 ture" appears to me to be but a half-sceptic. 
 He hath not followed his principles so far as 
 they lead him ; but, after liaving, with un- 
 paralleled intrepidity and success, combated 
 vulgar prejudices, when he had but one 
 blow to strike, his courage fails him, he 
 fairly lays down his arms, and yields him- 
 self a captive to the most common of all 
 vulgar prejudices— I mean the belief of the 
 existence of his own impressions and ideas. * 
 
 to be a necessary form o( our conceptions of externnl 
 things, prudently declineil a-feiting that these un. 
 known things are, in l/iet»sflrcs. cxtencied. 
 
 Now, the doctrine of Kant has been rigoronslv 
 proved l)y Jaeolii and Firhie to t)e, in its legitimate 
 issue, a doctrine of absolute Ideali,-m ; and the de- 
 monstralions which the philotophcr of Koenigsberg 
 lias given of the existence of an external world, have 
 beeu long admitted, even by liis disciples themelves, 
 to he inconclusive. Hut our Scottish iihilosophers 
 appeal to an argument which the German philnso. 
 pher overtly rejected-the arguini n;, as it is c ilhil, 
 from common sense. In their hands however, this 
 argument is nnavailing ; (or, if it be good against the 
 conclusions of the Idealist, it is good ag.iiiist the pre- 
 mises which they allord him. '1 he common acns-c of 
 mankind only assures us of the (xistence of an ex- 
 ternal and exteiided world, in assuring usihatwe 
 arecoi. scions, not merely of the pha?iiomena of rnind 
 in relation to matte r, but of the phaijnomina of mat. 
 fer in relation to mind— in other words, that we are 
 immidlately percipient ol extended Ihing.s. 
 
 Reid himself seems to have become obscurely aware 
 of this condition ; and, though he niver retracted his 
 doctrine concerning the mere iui; csliuyi of rr/.-n / tt, 
 we find, in his " Kssays on the Intellectual Powi rs," 
 afsertions in regard to the immediate jKrception o( 
 external things, which would tend to shew that 
 his later vieus were more in unison with the ne- 
 ccHiary convictiuns of mankind. JJut of this agani. 
 — H. 
 
 ■ There is In this and the two following para- 
 Rr.-iphs a confusion and inaccuracy which it is re- 
 yuinte to notice — 'I here is no Mt-pticiMn possible 
 loucliing the (ads o( consciousness in themselves. 
 \\e cannot donbt that the pha'iioinena of conscious. 
 
 I beg, therefore, to have the honour of 
 making an addition to the sceptical system, 
 without which I conceive it cannot hang 
 together. I affirm, that the belief of the 
 existence of impressions and ideas, is as lit- 
 tle supported by reason, as that of the exist- 
 ence of minds and bodies. No man ever 
 did or could offer any reason for this belief. 
 
 ness are real, in so far as we are conscious of them 
 I cannot doubt, for example, that I am actually 
 conscious of a certain feeling of fragrance, and of 
 certain perceptions of colour, tigure, ,s.c. when I see 
 and smell a rose. Of the reality of these, as expe. 
 rienced, I cannot doubt, because they are facts of 
 consciousness ; and of consciousness 1 cannot doubt, 
 because such doubt being itself an act of conscious, 
 ness, W'Uld conti.idict, and, consequently, annihi. 
 late itself But ot all beyond the mere i)ha;nomenA 
 ot which we are corscious, we may— without fiar of 
 self-contradiction at least— doubt. I may, (or in- 
 stance, doubt whether the rose I see and .smell has 
 any existence beyond a phenomenal existence in 
 my consciousnes. I cannot doubt that I am con. 
 scious of it as something dderent from self, but whe- 
 ther it have, indeed, any reality beyond my mind— 
 whether the nnZ-scz/be not in truih only .t'c/— that 
 I may philosrphically question. In like manner, I 
 am conscious of the memory of a ceiiaio i)ast event. 
 Of the contents of this memory, as a pha^n.imenon 
 given in consciousness, scepticism is impossible. But 
 I may by possibility demur to the reality of all be- 
 yond these contents and the sphere of present con- 
 sciousness. 
 
 In Reid's strictures upon Hume, he confounds 
 two opposite things. He reproaches that philosopher 
 with ii.coiii^equcnce, in holding to '' the belief of the 
 existence of his own impressions and ideas." Now, 
 if, by the exiiicnce of impressions and ideas, Reid 
 meant their existence as mere phainomena of con. 
 sciousness his criticism is inept; for a dislielief of 
 their existence, as such plia?iiomena, would have 
 been a suicidal act in the sceptic. If, ag.nin, he 
 meant by nn, leisions and iiieas tlie hypothesis of 
 representative entities differint from the mind and 
 its moditieations ; in that case the olijection is 
 equally invalid. Hume was a sceptic; that is, he 
 ncccp td the premises afforded him by the digmatist, 
 and carried these premises to their legitimate con! 
 sequences. 'Jo blame Hiiine, therefore, for not having 
 douhtcd ot his borrowed principle^, is to blame the 
 sceptic for not performing a jiart altogether incon- 
 sistent with his vocation. iiut, in point of facr, 
 ■he hypolheis of such entities is o( no value to t.he 
 idealisi or sceptic. Impressions and ideas, viewed as 
 mental niodes, would have answered Hume's pur. 
 pose not a whit worse than impressions and irtc is 
 viewed as objects, but not as affections of mind. 
 The most consistent scheme of idealism known in 
 ihe history of philosophy is that ol I'icnte ; and 
 Fichte s idealism is Ibundcd on a basis which ex. 
 dudes that crude hypothesis of ideas on which alone 
 lieid imagined any doetrine of Idealism could pos. 
 sihly he csi.ilihshed. Ami is the acknowledged result 
 of the lichte.in dogniatiMn less a nihilism than the 
 scepticism of Hume? " Ihe sum to al,"says Tichte, 
 "is this: — I here is absolutely nolhing permanent 
 either wrhout ine or within me, but only an un. 
 Ceasing change. I know a sulutely nothing of any 
 exisiei.(!e, iiit even ol niy own. I myself know 
 nothing, and am nothing. Images (liilder) there 
 ate; they constitute all that apparently exists, ami 
 what they know of ihem^elve-. is after the manner 
 of images ; iina;;es that pass and vanish without 
 Iheie tieing aught to A'itiie,-s their transition ; th.it 
 consist m (act o( the images of images, wiihoul sig, 
 nilicance and wiihout an aim. 1 my-elf am one of 
 Ihe^e images; nay, I am not even tiuis much, hut 
 ' nly a confused iin.ige of images All reality is con. 
 verted into a inarvrlloiis dream, wiihonl a life to 
 d'°eiim ol, and without a iiiiikI to dnaiii ; inio n 
 dream made up only of a dr. am of iiself. rcrrep. 
 tion is a dream ; thought- Mm' source of nil the ex. 
 istcncc and all the reality winih I imagine to niyielf 
 o( my existence, o( my power of my de.»tin.ilion — 
 is the dream of that dream. " — II.
 
 130 
 
 OF THE HUMAN MIND. 
 
 Des Cartes took it for granted, that lie 
 thought, and had sensations and ideas ; so 
 have Jill liis followers done. Even the hero 
 of scepticism hath yielded this point, I crave 
 leave to say, weaJily and imprudently. I 
 say so, because I am persuaded that there 
 is no principle of his philosophy that obliged 
 him to make this concession. And what is 
 there in impressions and ideas so formid- 
 able, that this all-conquering philosophy, 
 after triumphing over every other existence, 
 should pay homage to them ? Besides, the 
 concession is dangerous : for belief is of 
 such a nature, that, if you leave any root, 
 it will spread ; and you may more easily 
 pull it up altogether, than say, Hitherto 
 shalt thou go and no further ; the existence 
 of impressions and ideas I give up to thee ; 
 but see thou pretend to nothing more. A 
 thorough and consistent sceptic will never, 
 therefore, yield this point ; and while he 
 holds it, you can never oblige him to yield 
 anything else. 
 
 To such a sceptic I have nothing to say ; 
 but of the semi-sceptics, I should beg to 
 know, why they believe the existence of 
 their impressions and ideas. The true 
 reason I take to be, because they cannot 
 help it ; and the same reason will lead them 
 to believe many other things. 
 
 All reasoning must be from first prin- 
 ciples ; and for first principles no other 
 reason can be given but this, that, by the 
 constitution of our nature, we are upder 
 a necessity of assenting to them. Such 
 principles are parts of our constitution, no 
 less than the power of thinking : reason 
 can neither make nor destroy them ; nor 
 can it do anything without them : it is like 
 a telescope, which may help a man to see 
 farther, who hath eyes ; but, without eyes, 
 a telescope shews nothing at all. A ma- 
 thematician cannot prove the truth of his 
 axioms, nor can he prove anything, unless 
 he takes them for granted. We cannot 
 prove the existence of our minds, nor even 
 of our thoughts and sensations. A histo- 
 rian, or a witness, can prove nothing, unless 
 it is taken for grarted that the memory 
 and senses may be trusted. A natural 
 philosopher can prove nothing, unless it is 
 taken for granted that the course of nature 
 is steady and uniform. 
 
 How or when I got such first principles, 
 upon which I build all my reasoning, I 
 know not ; for I had them before I can 
 remember : but I am sure they are parts 
 of my constitution, and that I cannot throw 
 them off. That our thoughts and sensa- 
 tions must have a subject, which we call 
 ourself, is not therefore an opinion got by 
 reasoning, but a natural principle. That 
 our sensations of touch indicate something 
 external, extended, figured, hard or soft, 
 is not a deduction of reason, but a natural 
 
 principle. The belief of it, and the very 
 conception of it, are equally parts of our 
 constitution. If we are deceived in it, we 
 are deceived by Him that made us, and 
 there is no remedy.* 
 
 I do not mean to affirm, that the sensa- 
 tions of touch do, from the very first, sug- 
 gest the same notions of body and its qua- 
 lities which they do when we are grown 
 up. Perliaps Nature is frugal in this, as 
 in her other operations. The passion of 
 love, with all its concomitant sentiments 
 and desires, is naturally suggested by the 
 perception of beauty in the other sex ; yet 
 the same perception does not suggest the 
 tender passion till a certain period of life. 
 A blow given to an infant, raises grief and 
 lamentation ; but when he grows up, it as 
 naturally stirs resentment, and prompts him 
 to resistance. Perhaps a child in the womb, 
 or for some short period of its existence, is 
 merely a sentient being ; the faculties by 
 which it perceives an external world, by 
 which it reflects on its own thoughts, and 
 existence, and relation to other things, as 
 well as its reasoning and moral faculties, 
 unfold themselves by degrees ; so that it is 
 inspired with the various principles of com- 
 mon sense, as with the passions of love and 
 resentment, when it has occ.'sion for thera. 
 
 Section VIII. 
 
 OF THE SYSTEMS OF PHILOSOPHERS CONCERN- 
 ING THE SENSES. -f- 
 
 All the systems of philosophers about our 
 senses and their objects have split upon 
 this rock, of not distinguishine properly 
 
 * The philosophers who have most loudly appealed 
 to the veracity of God, and the natural conviction of 
 mankind, in refutation of certain obnoxious '^nncla. 
 sions, have too often silently contradicted that vera. 
 city and thnse convictions, when opposed to certain 
 favourite opinions. But it is evident that such autho. 
 rity is either good for all, or good for nothing. Our 
 natural consciousness assures us (and the/oc< of that 
 assurance is admitted by philosophers otail opinions) 
 that we have an immediate knowledge of the very 
 things themselves of an external and extended world; 
 and, on tliegroundotthisknowledgealone, isthebelief 
 oi mankind founded, that such a world really exists. 
 Reid ought, therefore, either to have given up his 
 doctrine of the mere suggestion of extension, &c., as 
 subjective notions, on the occasion of sensation, or 
 not to appc^il to the Divine veracity, and thecommon 
 sense of mankind, in favour of conclusions of which 
 that doctrine subverts the foundation. In this in. 
 consistency, Reid has, however, besides Des Cartes, 
 many distinguished copartners. — H. 
 
 f On this subject, see " Essays on the Intellectual 
 Powers," Essay II., chap. 7-15, and the notes there, 
 on. It is perhaps proper to recall to the reader'sat. 
 tentinn, that, by the Ideal Theory, Reid always 
 understands the ruder form of the doctrine, which 
 holds that ideas are entities, different both from the 
 external object and from the percipient mind, and 
 that he had no conception of the liner form of that 
 doctrine, which holds that all that we are conscious 
 of in perception, (of course also in imagination,) is 
 only a mcdtfication of the mind itself— See Note 
 C— H.
 
 OF TOUCH. 
 
 131 
 
 Bensations which can have no existence but 
 when they are feh, fiom the things sug- 
 gested by them. Aristotle — with as dis- 
 tinguishing a head as ever appUcd to philoso- 
 phical disquisitions — confounds these two; 
 and makes every sensation to be the form, 
 without the matter, of the thing perceived 
 by it. As the impression of a seal upon 
 wax has the form of the seal but nothing of 
 the matter of it, so he conceived our sensa- 
 tions to be impressions upon the mind, which 
 bear the image, likeness, or form of the 
 external thing perceived, without the mat- 
 ter of it. Colour, sound, and smell, as well 
 as extension, figure, and hardness, are, 
 according to him, various forms of matter : 
 our sensations are the same forms im- 
 printed on the mind, and perceived in its 
 own intellect. It is evident from this, that 
 Aristotle made no distinction between prim- 
 ary and secondary qualities of bodies, al- 
 though that distinction was made by De- 
 mocritus, Epicurus, and others of the an- 
 cients. " 
 
 Des Cartes, Malebranche, and Locke, 
 revived t!ie distinction between primary and 
 secondary qualities ; but they made the 
 secondary qualities mere sensations, and 
 the primary ones resemblances of our sens- 
 ations. They maintained that colour, 
 sound, and heat, are not anything in bodies, 
 but sensations of the mind ; at the same 
 time, they acknowledged some particular 
 texture or modification of the body to be 
 the cause or occasion of those sensations ; 
 but to this modification they gave no name. 
 Whereas, by the vulgar, the names of col- 
 our, heat, and sound, are but rarely applied 
 to the sensations, and most commonly to 
 those unknown causes of them, as hath been 
 already explained. The constitution of our 
 nature leads us rather to attend to tlie things 
 signified by the sensation than to the sensa- 
 tion itself, and to give a name to the former 
 rather tlian to the latter. TIius we see, 
 that, with regard to secondary qualities, 
 these philosophers thought with the vulgar, 
 and with common sense. Their paradoxes 
 were only an abuse of words ; for when 
 they maintain, as an important modern 
 discovery, that there is no heat in the fire, 
 they mean no more, than that the fire does 
 not feel heat, wjiich everyone knew before. 
 
 With regard to primary qualities, these 
 philosophers erred more grossly. They 
 indeed belic's'ed the existence of those qua- 
 lities ; but they did not at all attend to 
 the sensations that suggest them, whicii, 
 having no names, have been as little con- 
 sidered as if they had no existence. Tlioy 
 were aware that figure, extension, and 
 
 • On thin lait, neo ArisVUc Of Anima, L. HI, 
 c. I, and Mrtfip/i. I.. Ill.c. .') — I lie Arisiotclic (lis. 
 tinction of Jii it and ircund qmlitic* was of another 
 kind— H. See Note D, p. H29 l>. 
 
 hardness, are perceived by means of sens- 
 ations of touch ; whence they rashly con- 
 cluded, that these sensations must be images 
 and resemblances of figure, extension, and 
 hardness- 
 
 The received hypothesis of ideas natur- 
 ally led them to this conclusion : and indeed 
 cannot consist with any other ; for, accord- 
 ing to that hypothesis, external things 
 must be perceived by means of images of 
 them in the mind ; and what can those 
 images of external things in the mind be, but 
 the sensations by which we perceive them ? 
 
 This, however, was to draw a conclusion 
 from a hypothesis against fact. We need 
 not have recourse to any hypothesis to 
 know what our sensations are, or what 
 they are like. By a proper degree of re- 
 flection and attention we may understand 
 them perfectly, and be as certain that they 
 are not like any quality of body, as we can 
 be, that the toothache is not like a triangle. 
 How a sensation should instantly make us 
 conceive and believe the existence of an 
 external thing altogether unhke to it, I do 
 not pretend to know ; and when I say that 
 the one suggests the other, I mean not to 
 explain the manner of their connection, 
 but to express a fact, which every one may 
 be conscious of — namely, that, by a law of 
 our nature, such a conception and belief 
 constantly and immediately follow the sens- 
 ation. 
 
 Bishop Berkeley gave new light to this 
 subject, by shewing, that the qualities of 
 an inanimate thing, such as matter is con- 
 ceived to be, cannot resemble any sensa- 
 tion ; that it is impossible to conceive any- 
 thing like the sensations of our minds, but 
 the sensations of other minds. Every one 
 that attends properly to his sensations must 
 assent to this ; yet it bad escaped all the 
 philosophers that came before Berkeley ; 
 it had escaped even the ingenious Locke, 
 who had so much practised reflection on 
 the operations of his own mind. So difli- 
 cult it is to attend properly even to our 
 own feelings. They are so accustomed to 
 pass through the mind unobserved, and 
 instantly to make way for that whicli na- 
 ture intended them to signify, that it is 
 extremely difiicult to stop, and survey 
 them ; and when we think we have ac- 
 quired this power, perhaps the mind still 
 fluctuates between the sensation and its 
 associated quality, so that they mix to- 
 gether, and present something to the ima- 
 gination that is compounded of both. 'J'hus, 
 in a globe or cylinder, whose opposite sides 
 are quite unlike in colour, if you turn it 
 slowly, the colours are perfectly distinguish- 
 able, and their dissimilitude is manifest ; 
 but if it is turned fast, tliey lose tlieir dis- 
 tinction, and seem to be of one and tlie sanio 
 colour. 
 
 K 2
 
 132 
 
 OF THE HUMAN MIND. 
 
 No succession can be more quick than 
 that of tangible quaUties to the sensations 
 with which nature has associated them : 
 but when one has once acquired tlie art 
 of making them separate and distinct ob- 
 jects of thought, he will then clearly per- 
 ceive that the maxim of Bishop Berkeley, 
 above-mentioned, is self-evident ; and that 
 the features of the face are not more un- 
 like to a passion of the mind which they 
 indicate, than the sensations of touch are 
 to the primary qualities of body. 
 
 But let us observe what use the Bishop 
 makes of this important discovery. Why, 
 he concludes, that we can have no con- 
 ception of an inanimate substance, such as 
 matter is conceived to be, or of any of its 
 qualities ; and that there is the strongest 
 ground to believe that there is no existence 
 in nature but minds, sensations, and ideas : 
 if there is any other kind of existences, it 
 must be what we neither have nor can 
 have any conception of. But how does 
 this follow ? Why, thus : We can have 
 no conception of anything but what resem- 
 bles some sensation or idea in our minds ; 
 but the sensations and ideas in our minds 
 can resemble nothing but the sensations 
 and ideas in other minds ; therefore, the 
 conclusion is evident. This argument, we 
 see, leans upon two propositions. The last 
 of them the ingenious author hath, indeed, 
 made evident to all that understand his 
 reasoning, and can attend to their own 
 sensations : but the first proposition he 
 never attempts to prove ; it is taken from 
 the doctrine of ideas, which hath been so 
 universally received by philosophers, that 
 it was thought to need no proof. 
 
 We may here again observe, that this 
 acute writer argues from a hypothesis against 
 fact, and against the common sense of man- 
 kind. That we can have no conception of 
 anything, unless there is some impression, 
 sensation, or idea, in our minds which re- 
 sembles it, is indeed an opmion which hath 
 been very generally received among philo- 
 sophers ; but it is neither self-evident, nor 
 hath it been clearly proved ; and therefore 
 it hath been more reasonalile to call in 
 question tliis doctrine of philosophers, than 
 to discard the material world, and by that 
 means expose philosophy to the ridicule of 
 all men who will not offer up common 
 sense as a sacrifice to metaphysics. 
 
 We ought, however, to do this justice 
 both to the Bishop of Cloyne and to the 
 author of the " Treatise of Human Nature," 
 to acknowledge, that their conclusions are 
 justly draAvn from the doctrine of ideas, 
 which has been so universally received. 
 On the other hand, from the character of 
 Bishop Berkeley, and of his predecessors, 
 Des Cartes, Locke, and Malebranche, we 
 may venture to say, that, if they had seen 
 
 all the consequences of this doctrine, as 
 clearly as the author before mentioned did, 
 they would have suspected it vehemently, 
 and examined it more carefully than they 
 appear to have done. 
 
 The theory of ideas, like the Trojan 
 horse, had a specious appearance both of 
 innocence and beauty ; but if those philo- 
 sophers had known that it carried in its 
 belly death and destruction to all science 
 and common sense, they would not have 
 broken down their walls to give it admit- 
 tance. 
 
 That we have clear and distinct con- 
 ceptions of extension, figure, motion, and 
 other attributes of body, which are neither 
 sensations, nor like any sensation, is a fact 
 of which we may be as certain as that we 
 have sensations. And that all mankind 
 have a fixed belief of an external material 
 world — a belief which is neither got by rea- 
 soning nor education, and a belief which 
 we cannot shake off, even when we seem 
 to have strong arguments against it and 
 no shadow of argument for it — is likewise a 
 fact, for which we have all the evidence 
 that the nature of the thing admits. These 
 facts are phsenomena of human nature, 
 from which we may justly argue against 
 any hypothesis, however generally received. 
 But to argue from a hypothesis against 
 facts, is contrary to the rules of true philo- 
 sophy. 
 
 CHAPTER VI. 
 
 OF SEEING. 
 
 Section I. 
 
 THE EXCELLENCE AND DIGNITY OF THIS 
 FACULTY. 
 
 The advances made in the knowledge of 
 optics in the last age and in the present, 
 and chiefly the discoveries of Sir Isaac 
 Newton, do honour, not to philosophy only, 
 but to human nature. Such discoveries 
 ought for ever to put to shame the ignoble 
 attempts of our modern sceptics to depre- 
 ciate the human understanding, and to dis- 
 pirit men in the search of truth, by repre- 
 senting the human faculties as fit for no- 
 thing but to lead us into absurdities and 
 contradictions. 
 
 Of the faculties called the Jive senses, 
 sight is without doubt the noblest. The 
 rays of light, which minister to this sense, 
 and of which, without it, we could never 
 have had the least conception, are the 
 most wonderful and astonishing part of 
 the inanimate creation. We must be satis- 
 fied of this, if we consider their extreme 
 minuteness ; their inconceivable velocity ;
 
 OF SliElNG. 
 
 133 
 
 the regular variety of colours which they 
 exhibit ; the invariable laws according 
 to which they are acted upon by other 
 bodies, in their reflections, inflections, and 
 refractions, without the least change of 
 their original properties ; and the facihty 
 with which they pervade bodies of great 
 density and of the closest texture, without 
 resistance, without crowding or disturbing 
 one another, without giving the least sensi- 
 ble impulse to the lightest bodies. 
 
 The structure of the eye, and of all its ap- 
 purtenances, the admirable contrivances of 
 nature for performing all its various exter- 
 nal and internal motions, and the variety 
 in the eyes of diff"erent animals, suited to 
 their several natures and ways of life, 
 clearly demonstrate this organ to be a mas- 
 terpiece of Nature's work. And he must 
 be very ignorant of what hath been dis- 
 covered about it, or have a very strange 
 cast of understanding, who can seriously 
 doubt whether or not the rays of light 
 and the eye were made for one another, 
 with consummate wisdom, and perfect skill 
 in optics. 
 
 If we shall suppose an order of beings, 
 endued with every Imman faculty but tliat 
 of sight, how incredible would it appear to 
 such beings, accustomed only to the slow 
 informations of touch, that, by the addition 
 of an organ, consisting of a ball and socket 
 of an inch diameter, they might be enabled, 
 in an instant of time, without changing 
 their place, to percei\ e the disposition of a 
 whole army or the order of a battle, the 
 figure of a magnificent palace or all the 
 variety of a landscape ! If a man were by 
 feeling to find out the figure of tlie peak of 
 Teneriff'e, or even of St Peter's Church at 
 Rome, it would be the work of a lifetime.* 
 
 It would appear stUl more incredible to 
 such beings as we liave supposed, if they 
 were informed of the discoveries which 
 may be made by this little organ in 
 things far beyond the reach of any other 
 sense : that by means of it we can find 
 our way in the patliloss ocean ; that we 
 can traverse the globe of the earth, deter- 
 mine its figure and dimensions, and deli- 
 neate every region of it ; — yea, that we 
 can measure the planetary orbs, and make 
 discoveries in tlie sphere of the fixed stars. 
 
 Would it not appear still more astonish- 
 ing to such beings, if they should be farther 
 informed, that, by means of this same organ, 
 we can perceive the tempers and disposi- 
 tions, the passions and affections, of our 
 fellow-creatures, even when they want most 
 to conceal them ? — that, when the tongue 
 
 * The Ihing would he imp'xisible. f/tt any ono 
 try by touch to a^ct■rlaltl the figure of a rnom, with 
 which hir ia prcviouhly unacquainted, and not alto, 
 gcthcr of the usual shape, and he wijl find that 
 touch will nffiird him but ulcnder aid — H. 
 
 is taught most artfully to he and dissemble, 
 the hypocrisy should appear in the counte- 
 nance to a discerning eye ? — and that, by 
 this organ, we can often perceive what is 
 straight and what is crooked in the mind as 
 well as in the body ? How many myste- 
 rious things must a blind man believe, if he 
 will give credit to the relations of those 
 that see ? Surely he needs as strong a 
 faith as is required of a good Christian. 
 
 It is not therefore without reason that 
 the faculty of seeing is looked upon, not 
 only as more noble than the other senses, 
 but as having something in it of a nature 
 superior to sensation. The evidence of 
 reason is called seeing, not feeling, smelling, 
 or tasting. Yea, we are wont to express 
 the manner of the Divine knowledge by see- 
 ing, as that kind of knowledge which is 
 most perfect in us. 
 
 Section II. 
 
 SIGHT DISCOVERS ALMOST NOTHING WHICH 
 THE BLIND MAY NOT COMPREHEND — THB 
 REASON OF THIS. 
 
 Notwithstanding what hath been said of 
 the dignity and superior nature of this 
 faculty, it is worthy of our observation, that 
 there is very little of the knowledge ac- 
 quired by sight, that may not be communi- 
 cated to a man born blmd. One who never 
 saw the Ught, may be learned and knowing 
 in every science, even in optics ; and may 
 make discoveries in every branch of philo- 
 sophy. He may understand as much as 
 another man, not only of the order, dis- 
 tances, and motions of the heavenly bodies ; 
 but of the nature of light, and of the laws 
 of the reflection and refraction of its rays. 
 He may understand distinctly how those 
 laws produce the phsenomena of the rain- 
 bow, the prism, the camera obscura. and 
 the magic lanthorn, and all the powers of 
 the microscope and telescope. This is a 
 fact sufliciently attested by experience. 
 
 In order to perceive the reason of it, we 
 must distinguish the appearance that objects 
 make to the eye, from the things suggested 
 by that appearance : and again, in the visi- 
 ble appearance of objects, we must dis- 
 tinguish the appearance of colour from 
 the appearance of extension, figure, and 
 motion. First, then, as to the visible 
 appearance of the figure, and motion, and 
 extension of bodies, 1 conceive that a man 
 born blind may have a distinct notion, if 
 not of the very things, at least of something 
 extremely like to them. IMay not a blind 
 man be made to conceive that a body mov- 
 ing directly from the eye, or directly to- 
 wards it, may ajipcar to be at rest ? and 
 that the same motion may nppfiir quicker
 
 134 
 
 OF THE HUMAN MIND. 
 
 or slower, according as it is nearer to the 
 eye or farther off, more direct or more ob- 
 lique ? May he not be made to conceive, 
 that a plain surface, in a certain position, 
 may appear as a straight line, and vary 
 its visible figure, as its position, or the posi- 
 tion of the eye, is varied ? — that a circle 
 seen obliquely will appear an ellipse ; and 
 a square, a rhombus, or an oblong rec- 
 tangle ? Dr Saunderson understood the 
 projection of the sphere, and the common 
 rules of perspective ; and if he did, he 
 must have understood all that I have men- 
 tioned. If there were any doubt of Dr 
 Saunderson's understanding these things, I 
 could mention my having heard him say in 
 conversation, that he found great difficulty 
 in understanding Dr Halley's demonstra- 
 tion of that proposition, that the angles 
 made by the circles of the sphere, are equal 
 to the angles made by their representatives 
 in the stereographic projection ; but, said 
 he, when I laid aside that demonstration, 
 and considered the proposition in my own 
 way, I saw clearly that it must be true. 
 Another gentleman, of undoubted credit 
 and judgment in these matters, who had 
 part in this conversation, remembers it 
 distinctly. 
 
 As to the appearance of colour, a blind 
 man must be more at a loss ; because he 
 hath no perception that resembles it. Yet 
 he may, by a kind of analogy, in part sup- 
 ply this defect. To those who see, a scar- 
 let colour signifies an unknown quality 
 in bodies, that makes to the eye an ap- 
 pearance which they are well acquainted 
 with and have often observed— to a blind 
 man, it signifies an unknown quality, that 
 makes to the eye an appearance which he 
 is unacquainted with. But he can conceive 
 the eye to be variously aff'ected by differ- 
 ent colours, as the nose is by diff'erent 
 smells, or the ear by different sounds. 
 Thus he can conceive scarlet to differ from 
 blue, as the sound of a trumpet does 
 from that of a drum ; or as the smell of 
 an orange differs from that of an apple. 
 It is impossible to know whether a scarlet 
 colour has the same appearance to me 
 which it hath to another man ; and, if the 
 appearances of it to different persons dif- 
 fered as much as colour does from sound, 
 they might never be able to discover this 
 difference. Hence, it appears obvious, 
 that a blind man might talk long about 
 colours distinctly and pertinently ; and, if 
 you were to examine him in the dark about 
 the nature, composition, and beauty of them, 
 he might be able to answer, so as not to 
 betray his defect. 
 
 We have seen how far a blind man may 
 go in the knowledge of the appearances 
 which things make to the eye. As to the 
 things which are suggestfd by them or 
 
 inferred from them, although he could 
 never discover them of liimself, yet he may 
 understand them perfectly by the inform- 
 ation of others. And everything of this 
 kind that enters hito our minds by the eye, 
 may enter into his by the ear. Thus, for 
 instance, he could never, if left to the di- 
 rection of his own faculties, have dreamed 
 of any such thing as light ; but he can be 
 informed of everything we know about 
 it. He can conceive, as distinctly as we, 
 the minuteness and velocity of its rays, 
 their various degrees of refrangibility and 
 reflexibility, and all the magical powers 
 and virtues of that wonderful element. 
 He could never of himself have found out, 
 that there are such bodies as the sun, 
 moon, and stars ; but he may be informed 
 of all the noble discoveries of astrono- 
 mers about their motions, and the laws 
 of nature by which they are regulated. 
 Thus, it appears, that there is very little 
 knowledge got by the eye, which may not 
 be communicated by language to those who 
 have no eyes. 
 
 If we should suppose that it were as 
 uncommon for men to see as it is to be 
 born blind, would not the few who had 
 this rare gift appear as prophets and in- 
 spired teachers to the many ? We conceive 
 inspiration to give a man no new faculty, 
 but to commimicate to him, in a new way, 
 and by extraordinary means, what tlie fa- 
 culties common to mankind can apprehend, 
 and what he can communicate to others 
 by ordinary means. On the supposition 
 we have made, sight would appear to the 
 blind very similar to this ; for the few who 
 had this gift, could communicate the know- 
 ledge acquired by it to those who had it 
 not. They could not, indeed, convey to 
 the blind any distinct notion of the manner 
 in which they acquired this knowledge. A 
 ball and socket would seem, to a blind 
 man, in this case, as improper an instru- 
 ment for acquiring such a variety and ex- 
 tent of knowledge, as a dream or a vision. 
 The manner in which a man who sees, 
 discerns so many things by means of the 
 eye, is as unintelligible to the blind, as the 
 manner in which a man may be inspired 
 with knowledge by the Almighty, is to 
 us. Ought the blind man, therefore, with- 
 out examination, to treat all pretences to 
 the gift of seeing as imposture ? Might he 
 not, if he were candid and tractable, find 
 reasonable evidence of the reality of this 
 gift in others, and draw great advantages 
 from it to himself ? 
 
 The distinction we have made between 
 the visible appearances of the objects of 
 sight, and things suggested by them, is ne- 
 cessary to give us a just notion of the in- 
 tention of nature in giving us eyes. If we 
 attend duly to the operation of our mind
 
 OF SKEING. 
 
 135 
 
 In the use of this faculty, we shall perceive 
 that the visible appearance of objects is 
 hardly ever regarded by us. It is not at 
 all made an object of thouj^ht or reflec- 
 tion, but serves only as a sign to introduce 
 to the mind something else, which may be 
 distinctly conceived bythose who neversaw. 
 
 Thus, the visible appearance of things in 
 my room varies almost every hour, accord- 
 ing as the day is clear or cloudy, as the sun 
 is in the east, or south, or west, and as my 
 eye is m one part of the room or in an- 
 other; but I never think of these variations, 
 otherwise than as signs of morning, noon, 
 or night, of a clear or cloudy sky. A book 
 or a chair has a different appearance to the 
 eye, in every different distance and posi- 
 tion ; yet we conceive it to be still the 
 same ; and, overlooking the appearance, we 
 immediately conceive the real figure, dis- 
 tance, and position of the body, of which 
 its visible or perspective appearance is a 
 sign and indication. 
 
 When I see a man at the distance of ten 
 yards, and afterwards see him at the dis- 
 tance of a hundred yards, his visible ap- 
 pearance, in its length, breadth, and all its 
 linear proportions, is ten times less in the 
 last case than it is in the first ; yet I do not 
 conceive him one inch dirainislied by this 
 diminution of his visible figure. Nay, I 
 do not in the least attend to this diminution, 
 even when I draw from it the conclusion 
 of his being at a greater distance. For such 
 is the subtilty of the mind's operation in 
 this case, that we draw the conclusion, with- 
 out perceiving that ever the premises en- 
 tered uito the mind. A thousand such in- 
 stances might be produced, in order to shew 
 that the visible appearances of objects are 
 intended by nature only as signs or indica- 
 tions ; and that the mind passes instantly 
 to the things signified, without making the 
 least reflection upon the sign, or even per- 
 ceiving that there is any such thing. It is 
 in a way somewhat similar, that the sounds 
 of a language, after it is become familiar, 
 are overlooked, and we attend only to the 
 things signified by them. 
 
 It is therefore a just and important ob- 
 servation of the Bishop of Cloyne, That 
 the visible appearance of objects is a kind 
 of language used by nature, to inform us 
 ^f their distance, magnitude, and figure. 
 And this observation liatli been very happily 
 applied by that ingenious writer, to the 
 sohitionof somepluenomena in optics, which 
 hafl before perplexed the greatest masters 
 in that science. The same observation is 
 further improved by tliejudicious Dr Smith, 
 in his 0[)tics, for ex[)hiiniiig the ajiparent 
 figure of the heavens, and the apparent 
 distances and magnitudes of objects seen 
 with glasses, or by tlie naked eye. 
 
 Avoiding as niiicli as poKsible the repe- 
 
 tition of what hath been said by these ex- 
 cellent writers, we shall avail ourselves of 
 the distinction between the signs that nature 
 useth in this visual language, and the things 
 signified by them ; and in what remains to 
 be said of sight, shall first make some ob- 
 servations upon the signs. 
 
 Section III. 
 
 OF THE VISIBLE APPEARANCES OF OBJECTS. 
 
 In this section we must speak of things 
 which are never made the object of re- 
 flection, though almost every moment pre- 
 sented to the mind. Nature intended them 
 only for signs ; and in the whole course 
 of life they are put to no other use. The 
 mind has acquired a confirmed and invet- 
 erate habit of inattention to them ; for 
 they no sooner appear, than quick as light- 
 ning the thing signified succeeds, and en- 
 grosses all our regard. They have no 
 name in language ; and, although we are 
 conscious of them when they pass through 
 the mind, yet their passage is so quick 
 and so familiar, that it is absolutely un- 
 heeded; nor do they leave any footsteps 
 of themselves, either in the memory or 
 imagination. That this is the case with 
 regard to the sensations of touch, hath been 
 shewn in the last chapter; and it holds 
 no less with regard to the visible appear- 
 ances of objects. 
 
 I cannot therefore entertain the hope of 
 being intelligible to those readers who have 
 not, by pains and practice, acquired the 
 habit of distinguishing the appearance of 
 objects to the eye, from the judgment which 
 we form by sight of their colour, distance, 
 magnitude, and figure. The only profes- 
 sion in life wherein it is necessary to make 
 this distinction, is that of paintin;:. The 
 painter hath occasion for an abstraction, 
 with regard to visible objects, somewhat 
 similar to that which we here require : and 
 this indeed is the most difficult part of his 
 art. For it is evident, that, if he could fix 
 in his imagination the visible appearance of 
 objects, without confounding it with the 
 things signified liy that appearance, it 
 would be as easy for liim to paint from the 
 life, and to give every figure its proper 
 shading and relief, and its persi)ective pro- 
 portions, as it is to paint from a copy. Per- 
 spective, shading, giving relief, and colour- 
 ing, are nothini^ else but copying the ap- 
 ])earance which things make to the eye. 
 We may therefore liorrow some light on 
 the subject of visilileapiiearaiu-ofromtliisart. 
 
 Let one look upon any familiar object, 
 such as a book, at different distances and 
 in diff'erent positions : is he not able to 
 affirm, n()on the testimony of his flitjht, that
 
 136 
 
 OF THE HUMAN MINP 
 
 it is the same book, the same object, whether 
 seen at the distance of one foot or of ten, 
 whether in one position or another ; that 
 the colour is the same, the dimensions the 
 same, and the figure the same, as far as 
 the eye can judge ? This surely must be 
 acknowledged. The same individual object 
 is presented to the mind, only placed at 
 different distances and in different posi- 
 tions. Let me ask, in the next place, 
 Whether this object has the same appear- 
 ance to the eye in these different distances ? 
 InfaUibly it hath not. For, 
 
 First, However certain our judgment 
 may be that the colour is the same, it is as 
 certain that it hath not the same appear- 
 ance at different distances. There is a 
 certain degradation of the colour, and a 
 certain confusion and indistinctness of the 
 minute parts, which is the natural conse- 
 quence of the removal of the object to a 
 greater distance. Those that are not 
 painters, or critics in painting, overlook 
 this; and cannot easily be persuaded, that 
 the colour of the same object hath a dif- 
 ferent appearance at the distance of one 
 foot and of ten, in the shade and in the 
 light. But the masters in painting know 
 how, by the degradation of the colour and 
 the confusion of the minute parts, figures 
 which are upon the same canvass, and at 
 the same distance from the eye, may be 
 made to represent objects which are at the 
 most unequal distances. They know how 
 to make the objects appear to be of the 
 same colour, by making their pictures 
 really of different colours, according to 
 their distances or shades. 
 
 Secondly, Every one who is acquainted 
 with the rules of perspective, knows that 
 the appearance of the figure of the book 
 must vary in every different position : yet 
 if you ask a man that has no notion of 
 perspective, whether the figure of it does 
 not appear to his eye to be the same in all 
 its different positions ? he can with a good 
 conscience affirm that it does. He hath 
 learned to make allowance for the variety 
 of visible figure arising from the difference 
 of position, and to draw the proper con- 
 clusions from it. But he draws these con- 
 clusions so readily and habitually, as to lose 
 sight of the premises : and therefore where 
 he hath made the same conclusion, he con- 
 ceives the visible appearance must have 
 been the same. 
 
 Thirdly, Let us consider the apparent 
 magnitude or dimensions of the book. 
 Whether I view it at the distance of one 
 foot or of ten feet, it seems to be about 
 seven inches long, five broad, and one 
 thick. I can judge of these dimensions 
 very nearly by the eye, and I judge them 
 to be the same at both distances. But 
 yet it is certain, that, at the distance of 
 
 one foot, its visible length and breadth is 
 about ten times as great as at the distance 
 of ten feet ; and consequently its surface is 
 about a hundred times as great. This great 
 change of apparent magnitude is altogether 
 overlooked, and every man is apt to im- 
 agine, that it appears to the eye of the 
 same size at both distances. Further, when 
 I look at the book, it seems plainly to have 
 three dimensions, of length, breadth, and 
 thickness : but it is certain that the visible 
 appearance hath no more than two, and 
 can be exactly represented upon a canvass 
 which hath only length and breadth. 
 
 In the last place, does not every man, by 
 sight, perceive the distance of the book 
 from his eye ? Can he not affirm with 
 certainty, that in one case it is not above 
 one foot distant, that in another it is ten ? 
 Nevertheless, it appears certain, that dis- 
 tance from the eye is no immediate object 
 of sight. There are certain things in the 
 visible appearance, which are signs of dis- 
 tance from the eye, and from which, as we 
 shall afterwards shew, we learn by experi- 
 ence to judge of that distance within cer- 
 tain limits ; but it seems beyond doubt, 
 that a man born blind, and suddenly made 
 to see, could form no judgment at first of 
 the distance of the objects which he saw. 
 The young man couched by Cheselden 
 thought, at first, that everything he saw 
 touched his eye," and learned only by ex- 
 perience to judge of the distance of visible 
 objects. 
 
 I have entered into this long detail, in 
 order to shew that the visible appearance 
 of an object is extremely different from the 
 notion of it which experience teaches us to 
 form by sight ; and to enable the reader to 
 attend to the visible appearance of colour, 
 figure, and extension, in visible things, 
 which is no common object of thought, but 
 must be carefully attended to by those who 
 would enter into the philosophy of this 
 sense, or would comprehend what shall be 
 said upon it. To a man newly made to 
 see, the visible appearance of objects would 
 be the same as to us ; but he would see 
 nothing at all of their real dimensions, as 
 we do. He could form no conjecture, by 
 means of his sight only, how many inches 
 or feet they were in length, breadth, or 
 thickness. He could perceive little or no- 
 thing of their real figure ; nor could he dis- 
 cern that this was a cube, that a sphere ; 
 that this was a cone, and that a cylinder. -j- 
 
 • Still they appeared external to the eye. — H. 
 
 + This is a misinterpretation of Cheselden, on 
 whose authority this statement is made ; though it 
 must be confessed that the mode in which the case of 
 the young man, couched by that distinguished sur. 
 geon, is report" d, riops not merit all the eulngia 
 that have been lavished on it. It is at once imper- 
 fect and indistinct. Thus, on the point in questions 
 Cheselden says; — " He (the patient) kne.v not t^e 
 shape of anything, i or any one thing from another,
 
 OF SEEING. 
 
 137 
 
 His eye could not inform him that this 
 object was near, and that more remote. 
 The habit of a man or of a woman, which 
 appeared to us of one uniform colour, vari- 
 ously folded and shaded, would present to 
 his eye neither fold or shade; but variety of 
 colour. In a word, his eyes, though ever 
 so perfect, would at first give him almost no 
 information of things without him. They 
 would indeed present the same api^earances 
 to him as they do to us, and speak the same 
 language ; but to him it is an unknown 
 language ; and, therefore, he would attend 
 only to the signs, without knowing the sig- 
 nification of them, whereas to us it is a lan- 
 guage perfectly familiar ; and, therefore, 
 we take no notice of the signs, but attend 
 only to the thing signified by them. 
 
 Section J V. 
 
 THAT COLOUR IS A QUALITY OF BODIES, NOT 
 A SENSATION OF THE MIND. 
 
 By colour, all men, who have not' been 
 tutored by modern philosophy, understand, 
 not a sensation of the mind, which can have 
 no existence when it is not perceived, but a 
 quality or modification of bodies, which 
 continues to be the same whether it is seen 
 or not. The searlet-i'ose which is before 
 me, is still a scarlet-rose when I shut my 
 
 however different in shape or magniturle; hu', upon 
 being told what things were, whose form he before 
 knew from feeling, he would carefully observe, that 
 he might know them again ; but, laving too many 
 objects to learn at once, he forgot many of them, 
 and (as he said) at Brst he learned to know, and again 
 forgot a thousand tl-.ings in a day. One i)articular 
 only, though it may appear trifling, 1 will relate: 
 Having often forgot which was the cat and which 
 the dog, he was ashamed to ask; but, catching the 
 cat, which he knew by feeling, he was observed to 
 look at ner steadfastly, and then, setting her down, 
 gaid, 'So, puss! I shall know you another time.'" 
 
 Hire, when Cheselden says, ■■ that his patient, 
 when recently couched, knew not the shape of any 
 thing, nor any one thing from another,' &c , this 
 cannot mean that he saw no difference bttwecn 
 objects of different shapes and sizes; for, if this inter. 
 pretation were adopted, the rest of the statement 
 becomes nonsense. If he had been altogether inca. 
 bable of apprehending differences, it could not be 
 said that, " being told what things were whose form 
 he before knew from feeling, he would carefully 
 observe, that he might know them again ;" for oh- 
 gervation supposes the power of discrimin.itioii, and, 
 in particular, the anecdote of the dog and cat would 
 be inconceivable on that hypothesis. It is plain that 
 Cheselden only meant to say, that the things which 
 the patient could previously distinguish and deno. 
 minate by touch, he could not now identify and refer 
 to their appellations by sight And this is what we 
 might, a priori, be assured of A sphere and a cube 
 would certainly make different impressions on him ; 
 but it is probable that he could not assign to each its 
 name, though, in this particular ras-, there is good 
 ground for holding that the shghtest consi.ieration 
 would enable a person, previou«ly a(c|uainled with 
 these figures, and aware that the one w;u a cube 
 and the other a splicre, to ciimect them with his 
 anterior experience, and to discriminate them by 
 name.— Set I'hiloi. Tram., l''<«, itu. 40^—11. 
 
 eyes, and was so at midnight when no eye 
 saw it. The colour remains when the 
 appearance ceases ; it remains the same 
 when the appearance changes. For when 
 I view this scarlet-rose through a pair of 
 green spectacles, the appearance is changed ; 
 but I do not conceive the colour of the rose 
 changed. To a person in the jaundice, it 
 has still another appearance ; but he is 
 easily convinced tliat the change is in his 
 eye, and not in the colour of the object. 
 Every different degree of light makes it 
 have a different appearance, and total dark- 
 ness takes away all appearance, but makes 
 not the least change in the colour of the 
 body. We may, by a variety of optical 
 experiments, change the appearance of 
 figure and magnitude in a body, as well as 
 that of colour ; we may make one body 
 appear to be ten. But all men believe, 
 that, as a multiplyuig glass does not really 
 produce ten guineas out of one, nor a mi- 
 croscope turn a guinea into a ten-pound 
 piece, so neither does a coloured glass 
 change the real colour of the object seen 
 through it, when it changes the appearance 
 of that colour. 
 
 The common language of mankind shews 
 evidently, that we ought to distinguish be- 
 tween the colour of a body, which is con- 
 ceived to be a fixed and permanent quality 
 in the body, and the appearance of that 
 colour to the eye, which may be varied a 
 thousand ways, by a variation of the light, 
 of the medium, or of the eye itself. The 
 permanent colour of the body is the cause 
 which, by the mediation of various kinds or 
 degrees of light, and of various transparent 
 bodies interposed, produces all this variety 
 of appearances. When a coloured body is 
 presented, there is a certain apparition to 
 the eye, or to the mind, which we have 
 called the appearance of colour. Mr Locke 
 calls it an iilea ; and, indeed, it may be 
 called so with the greatest propriety. This 
 idea can have no existence but when it is 
 perceived. It is a kind of thought, and can 
 only be the act of a ])urcipient or thinking 
 being. By the constitution of our nature, 
 we are led to conceive this idea as a sign of 
 something external, and are impatient till 
 we learn its meaning. A thousand experi- 
 ments for this purpose are made every day 
 by children, even before they come to the 
 use of reason. They look at things, they 
 handle them, they put them in various jio- 
 sitions, at different distances, and in difter- 
 ent lights. The ideas of sight, by these 
 means, come to be associated with, and 
 readily to suggest, things external, and al- 
 together unlike them. In particular, tliat 
 idea which we have called the ajipraraiicc 
 of ciiloiir, Huggeststhe conception and belief 
 of some unknown quality in the body which 
 occasions the idea ; and it is to this quality,
 
 138 
 
 OF THE HUMAN MIND 
 
 and not to the idea, that we give the name 
 oi colour.* The various colours, although 
 in their nature equally unknown, are easily 
 distinguished when we think or speak of 
 them, by being associated with the ideas 
 which they excite. In like manner, gravity, 
 magnetism, and electricity, although all 
 unknown qualities, are distinguished by 
 their different effects. As we grow up, the 
 mind acquires a habit of passing so rapidly 
 from the ideas of sight to the external 
 things suggested by them, that the ideas are 
 not in the least attended to, nor have they 
 names given them in common language. 
 
 When we think or speak of any parti- 
 cular colour, however simple the notion may 
 seem to be which is presented to the imagin- 
 ation, it is really in some sort compounded. 
 It involves an unknown cause and a known 
 effect. The name of colour belongs indeed 
 to the cause only, and not to the effect. 
 But, as the cause is unknown, we can form no 
 distinct conception of it but by its relation to 
 the known effect ; and, therefore, both go to- 
 gether in the imagination, and are so closely 
 united, that they are mistaken for one simple 
 object ofthought.t When I would conceive 
 those colours of bodies which we call scarlet 
 and blue — if I conceived them only as un- 
 known qualities, I could perceive no distinc- 
 tion between the one and the other. I must, 
 therefore, for the sake of distinction, join to 
 each of them, in my imagination, some 
 effect or some relation that is peculiar ; and 
 the most obvious distinction is, the appear- 
 ance which one and the other makes to the 
 eye. Hence the appearance is, in the imagin- 
 ation, so closely united with the quality 
 called a scarlet-colour, that they are apt to 
 be mistaken for one and the same thing, 
 although they are in reality so different and 
 so unlike, that one is an idea in the mind, 
 the other is a quality of body. 
 
 I conclude, then, that colour is not a 
 sensation, but a secondary quality of bodies, 
 in the sense we have already explained ; 
 that it is a certain power or virtue in bodies, 
 that in fair daylight exhibits to the eye an 
 appearance which is very familiar to us, 
 although it hath no name. Colour differs 
 from other secondary qualities in this, that, 
 whereas the name of the quality is sometimes 
 given to the sensation which indicates it, and 
 is occasioned by it, we never, as far as I can 
 judge, give the name of colour to the sens- 
 ation, but to the quality only.:]: Perhaps 
 
 *+t It is justly observed by Mr Stewart, that 
 these pissages seem inconsistent with each other. 
 If in the perception of colour, the sensation and 
 the quality " be so closely united as to be mis. 
 taken for one simple object of thought," does it not 
 obviously follow, that it is to this compounded notion 
 the name of colour must in general be given ? On 
 the other hand, when it is said t/iat the name of 
 colour is niver given to ihe sensation, but to the 
 quality only, does no' this imply, that every t;me 
 the word is pronounced, the quality is separated from 
 
 the reason of this may be, that the appear- 
 ances of the same colour are so various and 
 changeable, according to the different mo- 
 difications of the light, of the medium, and 
 of the eye, that language could not afford 
 names for them. And, indeed, they are .'■o 
 little interesting, that they are never at- 
 tended to, but serve only as signs to in- 
 troduce the things signified by them. 
 Nor ought it to appear mcredible, that 
 appearances so frequent and so familiar 
 should have no names, nor be made ob- 
 jects of thought ; since we have before 
 shewn that this is true of many sensations of 
 touch, which are no less frequent nor less 
 familiar. 
 
 Section V. 
 
 AN INFERENCE FROM THE PRECEDING. 
 
 From what hath been said about colour, 
 we may infer two things. The first is, that 
 one of the most remarkable paradoxes of 
 modern philosophy, which hath been uni- 
 versally esteemed as a great discovery, is, 
 in reality, when examined to the bottom, 
 nothing else but an abuse of word.s. The 
 paradox I mean is. That colour is not a 
 quality of bodies, but only an idea in the 
 mind. We have shewn, that the word 
 colour, as used by the vulgar, cannot signify 
 an idea in the mind, but a permanent 
 quality of body. We have shewn, that 
 there is really a permanent quality of body, 
 to which the common use of this word ex- 
 actly agrees. Can any stronger proof be 
 desired, that this quality is that to which 
 the vulgar give the name of colour ?■ If it 
 should be said, that this quality, to which 
 we give the name of colour, is unknown to 
 the vulgar, and, therefore, can have no 
 name among them, I answer, it is, indeed, 
 known only by its effects — that is, by its 
 exciting a certain idea in us ; but are there 
 not numberless quaUties of bodies which 
 are known only by their effects, to which, 
 notwithstanding, we find it necessary to 
 give names ? Medicine alone might fur- 
 nish us with a hundred instances of this 
 kind. Do not the words astringent-, narcotic, 
 epispastic, caustic, and innumerable others, 
 s'gnify qualities of bodies, which are known 
 only by their effects upon animal bodies ? 
 Why, then, should not the vulgar give a 
 name to a quality, whose effects are every 
 moment perceived by their eyes ? We 
 have all the reason, therefore, that the 
 nature of the thing admits, to think that 
 the vulgar apply the name of colour to that 
 quality of bodies which excites in us what 
 
 the sensation, even in the imagination of the vul- 
 gar ?-H.
 
 OF SEEING. 
 
 139 
 
 the philosophers call the idea of colour. 
 And that that there is such a quality in 
 bodies, all philosophers allow, who allow that 
 there is any such thing as body. Philo- 
 sophers have thought fit to leave that 
 quality of bodies which the vulgar call 
 colour, without a name, and to give the 
 name of colour to the idea or appearance, 
 to which, as we have shewn, the vulgar 
 give no name, because they never make it 
 an object of thought or reflection. Hence 
 it appears, that, when philosophers afiBrm 
 that colour is not La bodies, but in the 
 mind, and the vulgar affirm that colour is 
 not in the mind, but is a quality of bodies, 
 there is no difference between them about 
 things, but only about the meaning of a 
 word. 
 
 The ^Tilgar have undoubted right to give 
 names to things which they are daily con- 
 versant about ; and philosophers seem 
 justly chargeable with an abuse of language, 
 when they change the meaning of a com- 
 mon word, without giving warning. 
 
 If it is a good rule, to think with philo- 
 sophers and speak with the vulgar, it must 
 be right to speak with the vulgar when we 
 think with them, and not to shock them by 
 philosophical paradoxes, which, when put 
 into common language, express only the 
 common sense of mankind. 
 
 If you ask a man that is no philosopher, 
 what colour is, or what makes one body 
 appear white, another scarlet, he can- 
 not tell. He leaves that inquiry to philo- 
 sophers, and can embrace any hypothesis 
 about it, except that of our modem philo- 
 sophers, who affirm that colour is not in 
 body, but only in the mind. 
 
 Nothing appears more shocking to his 
 apprehension, than that visible objects 
 should have no colour, and that colour 
 should be in that which he conceives to be 
 invisible. Yet this strange paradox is not 
 only universally received, but considered as 
 one of tlie noblest discoveries of modern 
 philosophy. The ingenious Addison, in 
 the Spectator, No. 41.3, speaks thus of it : — 
 " I have here supposed tliat my reader is 
 acquainted with tiiat great modern discovery, 
 which is at present universally acknow- 
 ledged by all the inquirers into natural 
 philosophy — namely, that light and colours, 
 as apprehended by the iniiigination, are 
 only ideas in the mind, and not qualities 
 that have any existence in matter. As this 
 is a truth which has been proved incon- 
 testably l)y many modern philosophers, and 
 is, indeed, one of the finest speculations in 
 tiiat science, if tlie Knglisli reader would see 
 tlie notion explained at large, he may find it 
 in the eighth chapter of tlu; second book of 
 Locke's 'Essay on Human Understanding.'" 
 Mr Locke and Mr Addison are writers 
 who Iiavc dcservorl so well of mankind, that 
 
 one must feel some uneasiness in differing 
 from them, and would wish to ascribe all 
 the merit that is due to a discovery upon 
 which they put so high a value. And, in- 
 deed, it is just to acknowledge that Locke, 
 and other modern philosophers, on the sub- 
 ject of secondary qualities, have the merit 
 of distinguishing more accurately than those 
 that went before them, between the sensa- 
 tion in the mind, and that constitution or 
 quality of bodies which gives occasion to 
 the sensation. They have shewn clearly 
 that these two things are not only distinct, 
 but altogether unlike : that there is no 
 similitude between the effluvia of an odo- 
 rous body and the sensation of smell, or 
 between the vibrations of a sounding body 
 and the sensation of sound : that there can 
 be no resemblance between the feeling of 
 heat, and the constitution of the heated 
 body which occasions it ; or between the 
 appearance which a coloured body makes to 
 the eye, and the texture of the body which 
 causes that appearance. 
 
 Nor was the merit small of distinguishing 
 these things accurately ; because, however 
 different and unlike in their nature, they 
 have been always so associated in the ima- 
 gination, as to coalesce, as it were, into one 
 two-faced form, which, from its amphibious 
 nature, could not justly be appropriuted 
 either to body or mind ; and, until it was 
 properly distinguished into its different con- 
 stituent parts, it was impossible to assign to 
 either their just shares in it. None of the 
 ancient philosophers had made this distinc- 
 tion." The followers of Democritus and 
 Epicurus conceived the forms of heat, and 
 sound, and colour, to be in the mind only ; 
 but that our senses fallaciously represented 
 them as being in bodies. The Peripatetics 
 imagined that those forms are really in 
 bodies ; and that the images of them are 
 conveyed to the mind by our senses. •)- 
 
 The one system made the senses natur- 
 ally fallacious nnd deceitful ; the other 
 made the qualities of body to resemble the 
 sensations of the mind. Nor was it possible 
 to find a third, without making the distinc- 
 tion we have mentioned ; by which, indeed, 
 the errors of both these ancient systems are 
 avoided, and we are not left under the hard 
 necessity of behoving, either, on the one 
 hand, that our sensations are like to the 
 qualities of body, or, on the other, that 
 God hath given us one faculty to deceive us, 
 and another to detect the cheat. 
 
 • This is inaccurate The (listinctioii w;ia known 
 to tlie ancient i)hil(isoi)licr8 ; and Deninrritus was 
 fcenerally allowed to bo its autlior. 'I'liis Keid liiniseK 
 
 elsewhere inikr<i admits (See above, p. )•<;:), a ; a: d 
 
 p. l:tl, a)— 11. 
 
 t I'hi'se stateincnts coiicerninR both claskot of 
 |)hilosopher!) are vague and inoorreit. '1 he latter, 
 in general, ordy alliiwe<l n/iiriis for two seines. Sight 
 anil Hearing; lew admitted tlieni in Keeling; «nd 
 some rejected tlie.o allogetlier. — H.
 
 140 
 
 OF THE HUMAN MIND. 
 
 We desire, therefore, with pleasure, to 
 do justice to the doctrine of Locke, and 
 other modern philosophers, with regard to 
 colour and other secondary qualities, and 
 to ascribe to it its due merit, while we beg 
 leave to censure the language in which 
 they have expressed their doctrine. When 
 they had explained and established the dis- 
 tinction between the appearance which co- 
 lour makes to the eye, and the modifica- 
 tion of the coloured body which, by the 
 laws of nature, causes that appearance, 
 the question was, whether to give the 
 name of colour to the cause or to the ef- 
 fect ? By giving it, as they have done, to 
 the effect, they set philosophy apparently 
 in opposition to common sense, and expose 
 it to the ridicule of the vulgar. But had 
 they given the name of colour to the cause, 
 as they ought to have done, they must 
 then have affirmed, with the vulgar, that 
 colour is a quality of bodies ; and that 
 there is neither colour nor anything like 
 it in the mind. Their language, as well 
 as their sentiments, would have been per- 
 fectly agreeable to the common apprehen- 
 sions of mankind, and true Philosophy would 
 have joined hands with Common Sense. 
 As Locke was no enemy to common sense, 
 it may be presumed, that, in this instance, 
 as in some others, he was seduced by some 
 received hypothesis ; and that this was ac- 
 tually the case, will appear in the following 
 section. 
 
 Section VI. 
 
 THAT NONE OF OUR SENSATIONS ARE RE- 
 SEMBLANCES OF ANY OF THE QUAIITIES 
 OF BODIES. 
 
 A second inference is, that, although co- 
 lour is really a quality of body, yet it is 
 not represented to the mind by an idea or 
 sensation that resembles it ; on the con- 
 trary, it is suggested by an idea which does 
 not in the least resemble it. And this in- 
 ference is applicable, not to colour only, but 
 to all the qualities of body which we have 
 examined. 
 
 It deserves to be remarked, that, in the 
 analysis we have hitherto given of the ope- 
 rations of the five senses, and of the quali- 
 ties of bodies discovered by them, no in- 
 stance hath occurred, either of any sensation 
 which resembles any quality of body, or of 
 any quality of body whose image or resem- 
 blance is conveyed to the mind by means of 
 the senses. 
 
 There is no phsenomenon in nature more 
 unaccountable than the intercouise that is 
 carried on between the mind and the ex- 
 ternal world — there is no phaenomenon 
 which philosophical spirits have shewn 
 
 greater avidity to pry into, and to resolre. 
 It is agreed by all, that this intercourse is 
 carried on by means of the senses; and 
 this satisfies the vulgar curiosity, but not 
 the philosophic. Philosophers must have 
 some system, some hypothesis, that shews 
 the manner in which our senses make us 
 acquainted with external things. All the 
 fertility of human invention seems to have 
 produced only one hypothesis for this pur- 
 pose, which, therefore, hath been univer- 
 sally received ; and that is, that the mind, 
 like a mirror, receives the images of things 
 from without, by means of the senses ; so 
 that their use must be to convey these images 
 into the mind.* 
 
 Whether to these images of external 
 things in the mind, we give the name of 
 sensible forms, or sensible species, with the 
 Peripatetics, or the name of ideas of sensa- 
 tion, with Locke ; or whether, with later 
 philosophers, we distinguish seiisaiions, 
 which are immediately conveyed by the 
 senses, from idtas of sensation, which are 
 faint copies of our sensations retained in 
 the memory and imagination •,-\ these are 
 only differences about words. The hypo- 
 thesis I have mentioned is common to all 
 these different systems. 
 
 The necessary and allowed consequence 
 of this hypothesis is, that no material thinf/, 
 nor any quality of material things, can be 
 conceived by us, or made an ol'ject oj 
 thouyht, until its image is conveyed to the 
 mind by means of the senses. We shall 
 examine this hypothesis particularly after- 
 wards, and at this time only observe, that, 
 in consequence of it, one would naturally 
 expect, that to every quality and attribute 
 of body we know or can conceive, there 
 should be a sensation corresponding, which ^ 
 is the image and resemblance of that qua- 
 lity ; and that the sensations which have 
 no similitude or resemblance to body, or to 
 any of its qualities, should give us no con- 
 ception of a material world, or of anything 
 belonging to it. These things might be ex- 
 pected as the natural consequences of the 
 hypothesis we have mentioned. 
 
 Now, we have considered, in this and 
 the preceding chapters. Extension, Figure, 
 Solidity, Motion, Hardness, Roughness, as 
 well as Colour, Heat, and Cold, Sound, 
 Taste, and Smell. We have endeavoured 
 to shew that our nature and constitution 
 lead us to conceive these as qualities of 
 body, as all mankind have always con- 
 
 • This IS incorrect, especially as it asserts that 
 the one universal hypothesis of philosophy was, that 
 " the mind receives the images of things from with, 
 out," meaning by these images, immediate or repre. 
 sentative objects, different from the modifications of 
 the thinking subject itself. — H. 
 
 + He refers to Hume; Aristotle, however, and 
 Hobbes, liad previously called Imagination a decay- 
 ing tense.— -H.
 
 OF SEEING. 
 
 141 
 
 ceived them to be. We have likewise exa- 
 mined witli great attention the various 
 sensations we have by means of the five 
 senses, and are not able to find among 
 them all one single* image of body, or of 
 any of its qualities. From whence, then, 
 come those images of body and of its qua- 
 lities into the mind ? Let philosophers re- 
 solve this question. All I can say is, that 
 they come not by the senses. I am sure 
 that, by proper attention and care, I may 
 know my sensations, and be able to affirm 
 with certainty what they resemble, and what 
 they do not resemble. I have examined 
 them one by one, and compared them with 
 matter and its qualities ; and I cannot find 
 one of them that confesses a resembling 
 feature. 
 
 A truth so evident as this — that our sens- 
 ations are not images of matter, or of any 
 of its qualities — ought not to yield to a hy- 
 pothesis such as that above-mentioned, how- 
 ever ancient, or however universally re- 
 ceived by philosophers ; nor can there be 
 any amicable union between the two. This 
 will appear by some reflections upon the 
 spirit of the ancient and modern philosophy 
 concerning sensation. 
 
 During the reign of the Peripatetic phi- 
 losophy, our sensations were not minutely 
 or accurately examined. The attention 
 of philosophers, as well as of the vulgar, 
 was turned to the thuigs signified by them : 
 therefore, in consequence of the common 
 hypothesis, it was taken for granted, that 
 all the sensations we have from external 
 things, are the forms or images of these 
 external things. And thus the truth we 
 have mentioned yielded entirely to the hypo- 
 thesis, and was altogether suppressed by it. 
 
 Des Cartes gave a noble example of 
 turning our attention inward, and scruti- 
 nizing our sensations ; and this example 
 hath been very worthily followed by mo- 
 dern philosophers, particularly by Malc- 
 branche, Locke, Berkeley, and Hume. The 
 effect of this scrutiny hath been, a gradual 
 discovery of the truth above-mentioned — to 
 wit, the dissimilitude between the sensa- 
 tions of our minds, and the qualities or 
 attributes of an insentient inert substance, 
 Bucli as we conceive matter to be. But 
 this valuable and useful discovery, in its 
 different stages, hath still been unhappily 
 united to the ancient hypothesis — and from 
 this inauspicious match of opinions, so 
 unfriendly and discordant in their natures, 
 have arisen tliose monsters of paradox and 
 scepticism witli which the modern philoso- 
 phy is too justly chargeable. 
 
 Locke saw clearly, and proved incon- 
 tcstably, that the sensations we have by 
 taate, smell, and hearing, as well as the 
 
 * Ont linglf — a common but faulty pleonnsm. — 1 1. 
 
 sensations of colour, heat, and cold, are 
 not resemblances of anything in bodies ; 
 and in this he agrees with Des Cartes and 
 Malebranche. Joining this opinion with 
 the hypothesis, it follows necessarily, that 
 three senses of the five are cut off from 
 giving us any intelligence of the material 
 world, as being altogether inept for that 
 office. Smell, and taste, and sound, as well 
 as colour and heat, can have no more rela- 
 tion to body, than anger or gratitude ; nor 
 ought the former to be called qualities of 
 body, whether primary or secondary, any 
 more than the latter. For it was natural 
 and obvious to argue thus from that hypo- 
 thesis : If heat, and colour, and sound 
 are real qualities of body, the sensations 
 by which we perceive them must be re- 
 semblances of those qualities ; but these 
 sensations are not resemblances ; there- 
 fore, those are not real qualities of body. 
 
 We see, then, that Locke, having found 
 that the ideas of secondary qualities are no 
 resemblances, was compelled, by a hypo- 
 thesis common to all philosophers, to deny 
 that they are real qualities of body. It 
 is more difficult to assign a reason why, 
 after this, he should call them s^econdary 
 (jii'i/itics ; for this name, if I mistake not, 
 was of his invention.* Surely he did not 
 mean that they were secondary qualities of 
 the mind ; and I do not see with what pro- 
 priety, or even by what tolerable license, 
 he could call them secondary qualities of 
 body, after finding that they were no qua- 
 lities of body at all. In this, he seems to 
 have sacrificed to Common Sense, and to 
 have been led by her authority even in 
 opposition to his hypothesis. The same 
 sovereign mistress of our opinions that led 
 this philosopher to call those things second- 
 ary qualities of body, which, according to his 
 principles and reasonings, were no qualities 
 of body at all, hath led, not the vulgar of 
 all ages only, but jihilosophers also, and 
 even the disciples of Locke, to believe them 
 to be real qualities of body — she hath led 
 them to investigate, by experiments, the 
 nature of colour, and sound, and heat, in 
 bodies. Nor hath this investigation been 
 fruitless, as it must have been if there had 
 been no such thing in bodies ; on tjic con- 
 trary, it hath produced very noble and 
 useful discoveries, which make a very con- 
 siderable part of natural philosoi)liy. If, 
 tlien, natural phil(iS()|)hy be not a dream, 
 there is something in bodies wliich we call 
 colour, and heat, and sound. And if this 
 be so, the hypothesis from which the C(m- 
 
 • The tcrme First and Second, or Primnry and 
 Sico:t(tary qualities, were no more an luvrntioii of 
 I.cH'ke than the distinction whirh he applud lliein to 
 denote 'J he tirins 1 irst and Siroiid Oiiahtirs, 
 at I have noticed, in the Aristntehan phi O'-ophj:, 
 marked ont, however, a diSerent diaiiliUtiuu «M 
 qu ihtien than ttiat in question.— il.
 
 142 
 
 OF THE HUMAN MIND. 
 
 trary is concluded, must be false : for the 
 argument, leading to a false conclusion, 
 recoils against the hypothesis from which 
 it was drawn, and thus directs its force 
 backward. If the qualities of body were 
 known to us only by sensations that resem- 
 ble them, then colour, and sound, and 
 heat could be no qualities of body ; but 
 these are real qualities of body ; and, there- 
 fore, the qualities of body are not known 
 only by means of sensations that resemble 
 them. 
 
 But to proceed. What Locke had proved 
 with regard to the sensations we have by 
 Bmell, taste, and hearing, Bishop Berkeley 
 proved no less unanswerably with regard 
 to all our other sensations;* to wit, that 
 none of them can in the least resemble the 
 qualities of a lifeless and insentient being, 
 such as matter is conceived to be. Mr 
 Hume hath confirmed this by his authority 
 and reasoning. This opinion surely looks 
 with a very malign aspect upon the old hypo- 
 thesis ; yet that hypothesis hath still been 
 retained, and conjoined with it. And what 
 a brood of monsters hath this produced ! 
 
 The first-born of this union, and, per- 
 haps, the most harmless, was, That the 
 secondary qualities of body were mere sens- 
 ations of the mind. To pass by Male- 
 branche's notion of seeing all things in the 
 ideas of the divine mind,-f- as a foreigner, 
 never naturalized in this island ; the next 
 was Berkeley's system, That extension, 
 and figure, and hardness, and motion — that 
 land, and sea, and houses, and our own 
 bodies, as well as those of our wives, and 
 children, and friends — are nothing but ideas 
 of the mind : and that there is nothmg 
 existing in nature, but minds and ideas. 
 
 The progeny that followed, is still more 
 frightful ; so that it is surprising, that one 
 could be found wlio had the courage to act 
 the midwife, to rear it up, and to usher it 
 into the world. No causes nor effects ; no 
 substances, material or spiritual ; no evi- 
 dence, even in mathematical demonstration ; 
 no liberty nor active power ; nothing exist- 
 ing in nature, but impressions and ideas 
 following each other, without time, place, 
 or subject. Surely no age ever produced 
 such a system of opinions, justly deduced 
 with great acuteness, perspicuity, and ele- 
 gance, from a principle universally received. 
 
 * Bayle, before Berkeley, shewed that the reason, 
 ing of Malebranche against the external reality of 
 the secondary qualities, when carried to its legitimate 
 issue, subverted also that of the primary. — H. 
 
 t Malebranche, it should bo oliserved, distin- 
 guished more precisely than Des Cartes, or any pre. 
 vious philosopher, prunary from sccontlnry quali- 
 ties; and perception (idee) from sensation [zeuti- 
 tnent.) He regard 'd the sensation of the secondary 
 qualities as the mere subjective feeling which the 
 human mind had of its own affections ; but the per. 
 ception of the primary he considered as an objective 
 intuition it obtained of these, as represented in the 
 divine mind. — H. 
 
 The hypothesis we have mentioned is the 
 father of them all. The dissimilitude of 
 our sensations and feelings to external things, 
 is the innocent mother of most of them. 
 
 As it happens sometimes, in an arith- 
 metical operation, that two errors balance 
 one another, so that the conclusion is little 
 or nothing affected by them ; but when one 
 of them is corrected, and the other left, we 
 are led farther from tlie truth than by both 
 together : so it seems to have happened in 
 the Peripatetic philosophy of sensation, 
 compared with the modern. The Peripa- 
 tetics adopted two errors ; but the last 
 served as a corrective to the first, and ren" 
 dered it mild and gentle ; so that their 
 system had no tendency to scepticism. 
 The moderns have retained the first of those 
 errors, but have gradually detected and 
 corrected the last. The consequence hath 
 been, that the light we have struck out hath 
 created darkness, and scepticism hath ad- 
 vanced hand in hand with knowledge, 
 spreading its melancholy gloom, first over 
 the material world, and at last over the 
 whole face of nature. Such a phsenomenon 
 as this, is apt to stagger even the lovers of 
 light and knowledge, while its cause is latent ; 
 but, when that is detected, it may give hopes 
 that this darkness shall not be everlasting, 
 but that it shall be succeeded by a more 
 permanent light. 
 
 Section VII. 
 
 OF VISIBLE FIGURE AND EXTENSION'. 
 
 Although there is no resemblance, nor, 
 as far as we know, any necessary connec- 
 tion, between that quality in a body which 
 we call its colour, and the appearance which 
 that colour makes to the eye, it is quite 
 otherwise with regard to its Jigwe and nuiij- 
 nUude. There is certainly a resemblance, 
 and a necessary connection, between the 
 visible figure and magnitude of a body, and 
 its real figure and magnitude ; no man can 
 give a reason why a scarlet colour affects 
 the eye in the manner it does ; no man can 
 be sure that it affects his eye in the same 
 manner as it affects the eye of another, 
 and that it has the same appearance to him 
 as it has to another man ; — but we can assign 
 a reason why a circle placed obliquely to 
 the eye, should appear in the form of an 
 ellipse. The visible figure, magnitude, and 
 position may, by mathematical reasoning, 
 be deduced from the real ; and it may be 
 demonstrated, that every eye that sees dis- 
 tinctly and perfectly, must, in the same 
 situation, see it under this form, and no 
 other. Nay, we may venture to affirm, 
 that a man born blind, if he were instructed 
 in mathematics* would be able to determine
 
 OF SEEING. 
 
 143 
 
 the visible figure of a body, when its real 
 figure, distiince, and position, are given. 
 Dr Saunde'-son understood the projection 
 of the sphere, and perspective. Now, I 
 require no more knowledge in a blind man, 
 in order to his being able to determme the 
 visible fig ;re of bodies, than that he can 
 project the outline of a given body, upon 
 the surface of a hollow sphere, whose centre 
 is in the eye. This projection is the visible 
 figure he 'wants : for it is the same figure 
 with that which is projected upou the 
 tunica retina in vision. 
 
 A blind man can conceive lines drawn 
 from every point of the object to the centre 
 of the eye, making angles. He can con- 
 ceive that the length of the object will 
 appear greater or less, in proportion to the 
 angle which it subtends at the eye ; and 
 that, in like manner, the breadth, and in 
 general the distance, of any one point of the 
 object from any other point, will appear 
 greater or less, in proportion to the angles 
 which those distances subtend. He can 
 easily be made to conceive, that the visible 
 appearance has no thickness, any more than 
 a projection of the sphere, or a perspective 
 draught. He may be informed, that the 
 eye, until it is aided by experience, does 
 not represent one object as nearer or more 
 remote than another. Indeed, he would 
 probably conjecture this of himself, and be 
 ai)t to think that the rays of light must 
 make the same impression upon the eye, 
 whether they come from a greater or a less 
 distance. 
 
 These are all the principles which we 
 suppose our blind mathematician to have ; 
 and these he may certainly acquire by in- 
 formation and reflection. It is no less 
 certain, that, from these principles, having 
 given the real figure and magnitude of a 
 body, and its position and distance with 
 regard to the eye, he can find out its visible 
 figure and magnitude. He can demonstrate 
 In general, from these principles, that the 
 visible figure of all bodies will be the same 
 with that of their projection upon the sur- 
 face of a hollow sphere, when the eye is 
 placed in the centre. And he can demon- 
 strate that their visible magnitude will be 
 greater or less, according as their projec- 
 tion occupies a greater or less part of the 
 surface of this sphere. 
 
 To set this matter in another light, let 
 us distinguish betwixt the position of objects 
 with regard to the eye, and their distance 
 from it. Ob octs that lie in the same right 
 line drawn from the centre of the eye, liavc 
 the same position, however diiferent their 
 distances from the eye may be: but objects 
 which lie in diH'erent right lines drawn from 
 the eve's centre, have a different position ; 
 I nd this dilference of position is greater or 
 Icuu in proportion to the angle made at tin; 
 
 eye by the right lines mentioned. Having 
 thus defined what we mean by the position 
 of objects with regard to the eye, it is evi- 
 dent that, as the real figure of a body con- 
 sists in the situation of its several parts 
 with regard to one another, so its visible 
 figure consists in the position of its several 
 parts with regard to the eye ; and, as he 
 that hath a distinct conception of the situ- 
 ation of the parts of the body with regard 
 to one another, nmst have a distinct con- 
 ception of its real figure ; so he that con- 
 ceives distinctly the position of its several 
 parts with regard to the eye, must have a 
 distinct conception of its visible figure. 
 Now, there is nothing, surely, to hinder a 
 blind man from conceiving' the position of 
 the several parts of a body with regard to 
 the eye, any more than from conceiving 
 their situation with regard to one another ; 
 and, therefore, I conclude, that a blind man 
 may attain a distinct conception of the vis- 
 ible figure of bodies. " 
 
 Although we think the arguments that 
 have been offered are sufficient to prove 
 that a blind man may conceive the visible 
 extension and figure of bodies; yet, in order 
 to remove some prejudiccsagainstthis truth, 
 it will be of use to compare the notion which 
 a blind mathematician might form to him- 
 self of visible figure, with that which is pre- 
 sented to the eye in vision, and to observe 
 wherein they differ. 
 
 First, Visible figure is never presented to 
 the eye but in conjunction with colour : 
 and, although there be no connection be- 
 tween them from the nature of the things, 
 yet, having so invariably kept company to- 
 getlier, we are hardly able to disjoin them 
 even in our imagination. + What mightily 
 increases this difficulty is, that we have 
 never been accustomed to make visible 
 figure an object of thought. It is only used 
 as u sign, and, having served this purpose, 
 passes away, without leaving a trace behind. 
 The drawer or designer, whose business it 
 is to hunt this fugitive form, and to take a 
 copy of it, finds how difficult his task is, 
 after many years' labour and practice. 
 Happy ! if at last he can acquire the art of 
 arresting it in his imagination, until he can 
 delineate it. For then it is evident that 
 he must be able to draw as accurately from 
 the life as from a copy. But how few 
 of the professed masters of designing are 
 ever able to arrive at this degree of perfec- 
 tion ! It is no wonder, then, that we should 
 find so great difficulty in conceiving this 
 form aj)art from its constant associate, 
 
 • 'I lie most .ncciirntp otiscrvations of the blind 
 from birth evince, however, that their conceptiuiu 
 ot liKiire ,irc extremely limited. — II. 
 
 + 111 other words, that imrjlcndi-d colour cnn bo 
 (cu-eived— r«H lie iinaBiiud. (»t this paradox (which 
 i> also adopted by Mr Stew.irt) in the bcquel.— II.
 
 144 
 
 OF THE HUMAN MIND. 
 
 when it is so difficult to conceive it at all. 
 But our blind man's notion of visible 
 figure will not be associated with colour, of 
 which he hath no conception, but it will, 
 perhaps, be associated with hardness or 
 smoothness, with which he is acquainted by 
 touch. These different associations are apt 
 to impose upon us, and to make things 
 seem different, which, in reality, are the 
 same. 
 
 Secondly, The blind man forms the no- 
 tion of visible figure to himself, by thought, 
 and by mathematical reasoning from prin- 
 ciples ; whereas, the man that sees, has it 
 presented to his eye at once, without any 
 labour, without any reasoning, by a kind of 
 inspiration. A man may form to himself 
 the notion of a parabola, or a cycloid, from 
 the mathematical definition of those figures, 
 although he had never seen them drawn or 
 delineated. Another, who knows nothing 
 of the mathematical definition of the figures, 
 may see them delineated on paper, or feel 
 them cut out in wood. Each may have a 
 distinct conception of the figures, one by 
 mathematical reasoning, the other by sense. 
 Now, the blind man forms his notion of 
 visible figure in the same manner as the 
 first of these formed his notion of a para- 
 bola or a cycloid, which he never saw. 
 
 Thirdly, Visible figure leads the man 
 that sees, directly to the conception of the 
 real figure, of which it is a sign. But the 
 blind man's thoughts move in a contrary 
 direction. For he must first know the real 
 figure, distance, and situation of the body, 
 and from thence he slowly traces out the 
 visible figure by mathematical reasoning. 
 Nor does his nature lead him to conceive 
 this visible figure as a sign ; it is a creature 
 of his own reason and imagination. 
 
 Section VIII. 
 
 SOME QUERIES CONCERNING VISIBLE FlfiURE 
 ANSVv'ERED. 
 
 It may be asked, What kind of thing is 
 this visible figure ? Is it a Sensation, or 
 an Idea ? If it is an idea, from what sensa- 
 tion is it copied ? These questions may 
 seem trivial or impertinent to one who does 
 not know that there is a tribunal of inqui- 
 sition erected by certain modern philoso- 
 phers, before which everything in nature 
 must answer. The articles of inquisition 
 are few indeed, but very dreadful in their 
 consequences. They are only these : Is 
 the prisoner an Impression or an Idea ? 
 If an idea, from what impression copied ? 
 Now, if it appears that the prisoner is 
 neither an impression, nor an idea copied 
 from some impression, immediately, with- 
 out being allowed to ofifer anything in 
 
 arrest of judgment, he is sentenced to pass 
 out of existence, and to be, in all time to 
 come, an empty unmeaning sound, or the 
 giiost of a departed entity.* 
 
 Before this dreadful tribunal, cause and 
 effect, time and place, matter and spirit, 
 have been tried and cast : how then shall 
 such a poor fiimsy form as visible figure 
 stand before it ? It must even plead guilty, 
 and confess that it is neither an impression 
 nor an idea. For, alas ! it is notorious, 
 that it is extended in length' and breadth ; 
 it may be long or short, broad or narrow, 
 triangular, quadrangular, or circular ; and, 
 therefore, unless ideas and unpressions are 
 extended and figured, it cannot belong to 
 that category. 
 
 If it should still be asked, To what cate- 
 gory of beings does visible figure then be- 
 long ? I can only, in answer, give some 
 tokens, by which those who are better ac- 
 quainted with the categories, may chance 
 to find its place. It is, as we have said, 
 the position of the several parts of a figured 
 body with regard to the eye. The dif- 
 ferent positions of the several parts of the 
 body with regard to the eye, when put to- 
 gether, make a real figure, which is truly 
 extended in length and breadth, and which 
 represents a figure that is extended in 
 length, breadth, and thickness. In like 
 manner, a projection of the sphere is a real 
 figure, and hath length and breadth, but 
 represents the sphere, which hath three 
 dimensions. A projection of the sphere, 
 or a perspective view of a palace, is a re- 
 presentative in the very same sense as visi- 
 i)le figure is ; and wherever they have their 
 lodgings in the categories, this will be found 
 to dwell next door to them. 
 
 It may farther be asked. Whether there 
 be any sensation proper to visible figure, by 
 which it is suggested in vision ? — or by 
 what means it is presented to the mind ?+ 
 
 * " Where Kntity and Quiddity, 
 
 The ghosts of defunct bodies, fly." 
 
 Hi dibras. — H. 
 f " In Dr Reid's ' Inquiry,'" (says Mr Stewart, in 
 one of his last works, in reference to the following 
 reasoning,) " he has introduced a discussion con. 
 cerniiig the perception of visible figure, which has 
 puzzled me since the first time (more than forty years 
 ago) that I read his work- 1 he di-cussion relates te 
 thequestion, ' Wheiherthere beany sensation propel 
 to visible figure, by which it is suggested in visiim ?' 
 The result of the argument is, that ' our eye mi/c/it 
 have been so framed as to suggest the figure of the 
 object, without suggesting colnur or any other quali- 
 ty ; and, of consequence, there seems to be no sensa. 
 tion appropriated to visible figure ; thisquality lieing 
 suggested immidiaieli/ by the material imjiVession 
 upon the organ, of which impression we are not 
 conscious.' — Inqiiiiy, ikC. chap. vi. ^ 8. I'o my 
 apprehension, nothing can appear more m.mifest 
 than this, that, if there had been no variety in our 
 sensations of colour, and, still more, if we liad had no 
 sensation of C' lour whatsoever, the organ of sight 
 could have given us no in'ormation, either with re- 
 spect tafifruresoT todistarices : and, of consequence, 
 would have been as useless to us, as if we had been 
 afflicted, from the moment of our birth, with a gutla 
 serena." — Dissertatiun, &c., p. 66, note ; 'ii ed.
 
 OF SEEING. 
 
 14; 
 
 This is a question tf some importance, in 
 order to our having a distinct notion of tlie 
 faculty of seeing : and to give all the light 
 to it we can, it is necessary to compare this 
 sense with other senses, and to make some 
 suppositions, by which we may be enabled 
 to distinguish things that are apt to be con- 
 iounded, although they ai'e totally dif- 
 ferent. 
 
 There are three of our senses which give 
 us inteUigence of things at a distance :* 
 smell, hearing, and sight. In smelling and 
 •"n hearing, we have a sensation or impres- 
 sion upon the mind, which, by our consti- 
 tution, we conceive to be a sign of some- 
 thing external : but the position of this 
 external thing, with regard to the organ of 
 sense, is not presented to the mind along 
 with the sensation. When I hear the 
 sound of a cnach, I could not, previous to 
 experience, determine whether the sounding 
 body was above or below, to the right hand 
 or to the left. So that the sensation. sug- 
 gests to nie some external object as the 
 cause or occasion of it ; but it suggests not 
 the position of that object, whether it lies 
 in this direction or in that. The same 
 thing may be said with regard to smelling. 
 But the case is quite different with regard 
 to seeing. When I see an object, the ap- 
 pearance which the colour of it makes, may 
 be called the sensation, which suggests to 
 me some external thing as its cause ; but 
 it suggests likewise the individual direction 
 and position of this cause with regard to 
 the eye. I know it is precisely in such a 
 a direction, and in no other. At the same 
 time, I am not conscious of anything that 
 can be called sensation, but the sensation of 
 colour. The position of the coloured thing 
 is no sensation ; but it is by the laws of my 
 constitution presented to the mind along 
 with the colour, without any additional 
 sensation. 
 
 Let us suppose that the eye were so con- 
 stituted that the rays coming from any one 
 point of the object were not, as they are in 
 our eyes, collected in one point of the 
 retina, but diffused over the whole : it is 
 evident to those who understand tlio struc- 
 ture of the eye, that such an eye as we have 
 supposed, would shew the colour of a body 
 as our eyes do, but that it would neither 
 shew figure nor position. The operation 
 of such an eye would be precisely similar 
 to tliat of liearing and smell ; it w ould give 
 
 The quettions coriccrnirg the mutual dependence 
 of colour on extension, and of extension and figure 
 on colour. Ill I creep' ion and imagination, cannot be 
 diKiniKiiod in a Hot. note. 1 shall endeavour, in Note 
 H, to Bhiw tlal wo can ni'itliir see nor iniaRine 
 colour apart from extension, nor extension and figure 
 apart (roin (olour. — H. 
 
 * I'ropirly «peakinff, no>cri<« gives UBaKnowIe<lKe 
 i>! »\iy\ii lait what is iti immcdinlc contact with its 
 organ. All else is somelhiiigovcr and above ipcrcep. 
 lion— H. 
 
 no perception of figure or extension, but 
 merely of colour. Nor is the supposition 
 we have made altogether imaginary : for it 
 is nearly the case of most people who have 
 cataracts, whose crystalline, as Mr Chesel- 
 i!:,Q\\ observes, does not altogether exclude 
 the rays of light, but diffuses them over the 
 retina, so that such persons see things as 
 one does through a glass of broken gelly : 
 they perceive the colour, but nothing of 
 the figure or magnitude of objects.* 
 
 Again, if we should su])pose that smell 
 and sound were conveyed in right lines from 
 the objects, and that e\ery srensation of 
 hearuig and smell suggested the precise 
 direction or position of its object ; in this 
 case, the operations of hearing and smelling 
 would be similar to that of seeing : we 
 should smell and hear the figure of objects, 
 in the same sense as now we see it ; and 
 every smell and sound would be associated 
 with some figure m the imagination, as 
 colour is in our present state. -|- 
 
 * Rcid, as remarked by Mr Fearn, misinterprets 
 Chcselden in founding on the expressions of this 
 report, a proof of his own paradox, that-colour can 
 possibly be anobject of vision, apaii from extension. 
 There is no ground in that ie|ioit for ^uch an 
 inference ; for it contains absolutely nothmg to in- 
 validate, and much to support the doctrine — that, 
 though sensations of colour may be experienced 
 thiough the medium of an iinpe.fcct catara't, while 
 the.fignies of external objects are intercepted or 
 broken down ; yet th 't, in these sensations, colour 
 bting difl'used over the retina, must appear to us 
 extended, and of an extension limited by the bound, 
 aries of that sensitive membrane itself 'J he relative 
 passage of Chrselden is as follows:—" '1 hough we 
 say of the gentleman couched between thirteen and 
 fourteen years of age, that he was blind, as we do 
 of all people who have ripe cataracts, yet they are 
 never so Idind from thai Ciiui-e, but they can discern 
 day from night, and lor the most part in a strong 
 light distinguish black, white, and scarlet ; but the 
 light by which these perceptions are made, being let 
 in obliquely 'hrough tlie aqueous humour, or the 
 anterior surface of the crystalline, by which the ray* 
 cannot be brought into a focus upon the retina, they 
 can discern in no other manner than a sound eye can 
 through a glass of broken jelly, where a great variety 
 of siirlarrs so difti^rently refract the light, th.it the 
 several di^tillct pencils of rays cannot he collecteii by 
 the eye into their proper foci, wherefore the shape of 
 an o jcci in such a case c.iiino- be at all discerned, 
 though the colour may Aiid tin- it was with this 
 young gentleman, who, though he knew these colours 
 asunder 111 a good light, yet, when he saw them after 
 he was couched, the taint ideas he had of tluni before, 
 were nut sutticient for him to know lum by after- 
 wards, and thenfoie he did not think ihein the 
 same u I ii'h he h.n<l before known by tlio^e names " — 
 I here are also several statements in the repoif « hich 
 shew that thepaticnl was, on the neoveiy of distinct 
 virion, perfectly familiar with difRrences of visible 
 magnitude See Note K. — H 
 
 f I'o render this supposition possible, we must 
 in.t only change theo/i/<i7/i'C, but also thi' iiiltjcclive 
 conditions of smell and luaring; for, with oiir or. 
 gans of these senses, and our nervous system in go. 
 nerni, constituted as they are at (iresent, the resul* 
 would not be as avsumid, even were the ollaetoiy 
 iflluvia ami audible vil rations eonvrved in ri^lit 
 line- lioni liodirs to the nose and ear i'ut to Mip. 
 jiose both subjective and oljrctive conditions 1 hall, ed 
 is to suppose new qualities and ii' w senses iiltcgither ; 
 an hy|)'. thesis winch would haidly servo the |iurpo.se 
 of an ulu.^trallon, n mi/wii. 
 
 A 8inii1;ir hypothesis and illustration it to le 
 I' und in ( ondillat's " i raite den Seiiiutiunsi" but,
 
 146 
 
 OF THE HUMAN MIND. 
 
 We have reason to believe, that the rays 
 of hght make some impression upon the 
 retina ; but we are not conscious of this 
 impression ; nor liave anatomists or philo- 
 sophers been able to discover the nature and 
 effects of it ; whether it produces a vibra- 
 tion in the nerve, or the motion of some 
 subtile fluid contained in the nerve, or some- 
 thing different from eitlier, to which we 
 cannot give a name. Whatever it is, we 
 shall call it the malerial impression ; remem- 
 bering carefully, that it is not an impression 
 upon the mind, but upon the body ; and 
 that it is no sensation, nor can resemble 
 sensation, any more than figure or motion 
 can resemble thought. Now, this material 
 impression, made upon a particular point of 
 the retina, by the laws of our constitution, 
 suggests two things to the mind — namely, 
 the colour and the position of some exter- 
 nal object. No man can give a reason why 
 the same material impression might not 
 have suggested sound, or smell, or either 
 of these, along with the position of the object. 
 That it should suggest colour and position, 
 and nothing else, we can resolve only into 
 our constitution, or the will of our Maker. 
 And since there is no necessary connection 
 between these two things suggested by this 
 material impression, it might, if it had so 
 pleased our Creator, have suggested one oi 
 them without the other. Let us suppose, 
 therefore, since it plainly appears to be 
 possible, that our eyes had been so framed 
 as to suggest to us the position of the object, 
 without suggesting colour, or any other 
 quality : What is the consequence of this 
 supposition ? It is evidently this, that the 
 person endued with such an eye, would per- 
 ceive the visible figure of bodies, without 
 having any sensation or impression made 
 upon his mind. The figure he perceives is 
 altogether external ; and therefore cannot 
 be called an impression upon the mind, 
 without the grossest abuse of language. If 
 it should be said, that it is impossible to 
 perceive a figure, unless there be some im- 
 pression of it upon the mind, I beg leave 
 not to admit the impossibility of this without 
 some proof : and I can find none. Neither 
 can I conceive what is meant by an impres- 
 sion of figure upon the mind. I can conceive 
 an impression of figure upon wax, or upon 
 any body that is fit to receive it ; but an 
 impression of it upon the mind, is to me 
 quite unintelligible ; and, although I form 
 the most distinct conception of the figure, I 
 cannot, upon the strictest examination, find 
 any impression of it upon my mind. 
 
 If we suppose, last of all, that the eye 
 hath the power restored of perceiving colour. 
 
 as Mr Stewart observes, though thus anticipated, 
 there is no ground for tliiiiking that Reid was 
 at all acquainted with the writings of the French phi- 
 osophcr.— H. 
 
 I apprehend that it will be allowed, that 
 now it perceives figure in the very same 
 manner as before, with this difference only, 
 that colour is always joined with it. 
 
 In answer, therefore, to the question pro- 
 posed, there seems to be no sensation that 
 is appropriated to visible figure, or whose 
 office it is to suggest it. It seems to be 
 suggested immediately by the material im- 
 pression upon the organ, of which we are 
 not conscious : and why may not a material 
 impression upon the retina suggest visible 
 figure, as well as the material impression 
 made upon the hand, when we grasp a ball, 
 suggests real figure ? In the one case, one 
 and the same material impression, suggests 
 both colour and visible figure ; and in the 
 other case, one and the same material im- 
 pression suggests hardness, heat, or cold, 
 and real figure, all at the same time. 
 
 We shall conclude this section with-an- 
 other question upon this subject. Since the 
 visible figure of bodies is a real and exter- 
 nal object to the eye, as their tangible figure 
 is to the touch, it may be asked. Whence 
 arises the difficulty of attending to the first, 
 and the facility of attending to the last ? It 
 is certain that the first is more frequently 
 presented to the eye, than the last is to the 
 touch ; the first is as distinct and deter- 
 minate an object as the last, and seems in 
 its own nature as proper for speculation. 
 Yet so little hath it been attended to, that 
 it never had a name in any language, until 
 Bishop Berkeley gave it that which we have 
 used after his example, to distinguish it 
 from the figure which is the object of touch. 
 The difficulty of attending to the visible 
 figure of bodies, and making it an object of 
 thought, appears so similar to that which 
 we find in attending to our sensations, that 
 both have probably like causes. Nature 
 intended the visible figure as a sign of the 
 tangible figure and situation of bodies, and 
 hath taught us, by a kind of instinct, to put 
 it always to this use. Hence it happens, 
 that the mind passes over it with a rapid 
 motion, to attend to the things signified by 
 it. It is as unnatural to the mind to stop 
 at the visible figure, and attend to it, as it 
 is to a spherical body to stop upon an in- 
 clined plane. There is an inward principle, 
 which constantly carries it forward, and 
 which cannot be overcome but by a contrary 
 force. 
 
 There are other external things which 
 nature intended for signs ; and we find 
 this common to them all, that the mind is 
 disposed to overlook them, and to attend 
 only to the things signified by them. Thus 
 there are certain modifications of the hu- 
 man face, which are natural signs of the 
 present disposition of the mind. Every 
 man understands the meaning of these signs, 
 but not one of a hundred ever attended to
 
 OF SEEING. 
 
 147 
 
 the signs themselves, or knows anythuig 
 about tliem. Hence you may find many 
 an excellent practical physiognomist who 
 knows nothing of the proportions of a face, 
 nor can dehneate or describe the expression 
 of any one passion. 
 
 An excellent painter or statuary can 
 tell, not only what are the proportions of a 
 good face, but what changes every passion 
 makes in it. This, however, is one of the 
 chief mysteries of his art, to the acquisition 
 ofwhieli infinite labourand attention, as well 
 as a happy genius, are required ; but when 
 he puts his art in practice, and happily ex- 
 presses a passion by its proper signs, every 
 one understands the meaning of these signs, 
 without art, and without reflection. 
 
 What has been said of painting, might 
 easily be applied to all the fine arts. The 
 difficulty in them all consists in knowing 
 and attending to those natural signs where- 
 of every man understands the meaning. 
 
 We pass from the sign to the thing sig- 
 nified, with ease, and by natural impulse ; 
 but to go backward from the thing signi- 
 fied to the sign, is a work of labour and 
 difficulty. Visible figure, therefore, being 
 intended by nature to be a sign, we pass on 
 immediately to the thing signified, and can- 
 not easily return to give any attention to 
 the sign. 
 
 Nothing shews more clearly our indis- 
 position to attend to visible figure and vi- 
 sible extension than this — that, although 
 mathematical reasoning is no less appli- 
 cable to them, than to tangible figure and 
 extension, yet they have entirely escaped 
 the notice of mathematicians. While that 
 figure and that extension which are objects 
 of touch, have been tortured ten thousand 
 ways for twenty centuries, and a very 
 noble system of science has been drawn 
 out of them, not a single proposition do 
 we find with regard to the figure and ex- 
 tension which are the immediate objects of 
 sight ! 
 
 When the geometrician draws a diagram 
 with the most perfect accuracy — when he 
 keeps his eye fixed upon it, while he goes 
 through a long process of reasoning, and 
 demonstrates the relations of the several 
 parts of his figure — he does not consider 
 that the visible figure presented to his eye, 
 is only the representative of a tangible figure, 
 upon wiiieh all his attention is fixed ; he 
 does not consider tliat these two figures 
 have really ditferent properties ; and that, 
 what lie demonstrates to be true of the one, 
 is not true of the other. 
 
 This, perhaps, will seem so great a para- 
 dox, even to mathtrmaticians, as to require 
 demonstration before it can be believed. 
 Nor is the demonstration at all difficult, if 
 the reader will have patience to enter Ijut 
 a little into the mathematical consideration 
 
 of visible figure, which we shall call (lie 
 geometry of visible s. 
 
 Sec. ion IX. 
 
 OK THE GEOMETRY OK VISIBI.ES.* 
 
 In this geometry, the definitions of a point ; 
 of a line, whether straight or curve ; of an 
 angle, whether acute, or right, or obtuse ; 
 and of a circle— are the same as in common 
 geometry. The mathematical reader will 
 easily enter into the whole mystery of this 
 geometry, if he attends duly to these few 
 evident principles. 
 
 1. Supposing the eye placed in the centre 
 of a sphere, every great circle of the sphere 
 will have the same appearance to the eye 
 as if it was a straight line ; for the curva- 
 ture of the circle being turned directly to- 
 ward the eye, is not perceived by it. And, 
 for the same reason, any line which is drawn 
 in the plane of a great circle of the sphere, 
 whether it be in reality straight or curve, 
 will appear straight to the eye. 
 
 2. Every visible right line will appear to 
 comcide with some great circle of the 
 sphere ; and the circumference of that great 
 circle, even when it is produced until it 
 returns into itself, will appear to be a con- 
 tinuation of the same visible right line, all 
 the parts of it being visibly in directum. 
 J'or the eye, perceiving only the position of 
 objects with regard to itself, and not their 
 distance, will see those points in the same 
 visible place which have the same position 
 with regard to the eye, how different soever 
 their distances from it may be. Now, since 
 a plane passing through the eye and a given 
 visible right line, will be the jjlane of some 
 great circle of the sphere, every point of the 
 visible right line will have the same position 
 as some pohit of the great circle ; therefore, 
 they will both have the same visible place, 
 and coincide to the eye; and the whole 
 circumference of the great circle, continued 
 even until it returns into itself, will appear 
 to be a continuation of the same visible 
 right line. 
 
 Hence it follows — 
 
 3. That every visible right line, when it 
 is continued in directum, as far as it may be 
 continued, will be rej) esented by a great 
 circle of a sphere, in whose centre the eye 
 is jilacod. It follows — 
 
 4. That the visible angle comi)rehendcd 
 under two visible right lines, is eiiual to the 
 spherical angle conqirehended under the 
 two great circles which are the representa- 
 tives of these visibU; lines. For, since the 
 visible lines appear to coincide with the 
 
 • How docs this (liltor from a ddclriiie of rcrsju'C- 
 
 ivc? At any ate. the notion is Hcrki'lcy'i". Com. 
 
 laro " New I'heory ol Vi>ion," ^^ I5:t— l&U.— 11. 
 
 I, y
 
 148 
 
 OF THE HUMAN MIND. 
 
 great circles, the visible angle compre- 
 hended under the former must be equal to 
 the visible angle comprehended under the 
 latter. But the visible angle comprehended 
 under the two great circles, when seen from 
 the centre, is of the same magnitude with 
 the spherical angle which they really com- 
 prehend, as mathematicians know ; there- 
 fore, the visible angle made by any two 
 visible lines is equal to the spherical angle 
 made by the two great circles of the sphere 
 which are their representatives. 
 
 5. Hence it is evident, that every visible 
 right-lined triangle will coincide in all its 
 parts with some spherical triangle. The 
 sides of the one will appear equal to the 
 sides of the other, and the angles of the 
 one to the angles of the other, each to each ; 
 and, therefore, the whole of the one triangle 
 will appear equal to the whole of the other. 
 In a word, to the eye they will be one and 
 the same, and have the same mathematical 
 properties. The properties, therefore, of 
 visible right-lined triangles are not the same 
 with the properties of plain triangles, but 
 are the same with those of spherical tri- 
 angles. 
 
 6. Every lesser circle of the sphere will 
 appear a circle to the eye, placed, as we 
 have supposed all along, in the centre of 
 the sphere ; and, on the other hand, every 
 visible circle will appear to coincide with 
 some lesser circle of the sphere. 
 
 7. Moreover, the whole surface of the 
 sphere will represent the whole of visible 
 space ; for, since every visible point coin- 
 cides with some point of the surface of the 
 sphere, and has the same visible place, it 
 follows, that all the parts of the spherical 
 surface taken together, will represent all 
 possible visible places — that is, the whole of 
 visible space. And from this it follows, in 
 the last place — 
 
 8. That every visible figure will be repre- 
 sented by that part of the surface of the 
 sphere on which it might be projected, the 
 eye being in the centre. And every such 
 visible figure will bear the same ratio to the 
 whole of visible space, as the part of the 
 spherical surface which represents it, bears 
 to the whole spherical surface. 
 
 The mathematical reader, I hope, will 
 enter into these principles with perfect 
 facility, and will as easily perceive that the 
 following propositions with regard to visible 
 figure and space, which we offer only as a 
 specimen, may be mathematically demon- 
 strated from them, and are not less true nor 
 less evident than the propositions of Euclid, 
 with regard to tangible figures. 
 
 P)Op. 1. Every right line being produced, 
 will at last return into itself. 
 
 2. A right line, returning into itself, is 
 the longest possible right line ; and all other 
 right lines bear a finite ratio to it. 
 
 3. A right line returning into itself, 
 divides the whole of visible space into two 
 equal parts, which will both be compre- 
 hended under this right line. 
 
 4. The whole of visible space beais a 
 finite ratio to any part of it. 
 
 5. Any two right lines being produced, 
 will meet in two points, and mutually 
 bisect each other 
 
 C. If two lines be parallel — that is, every 
 where equally distant from each other — 
 they cannot both be straight. 
 
 7. Any right line being given, a point 
 may be found, which is at the same dis- 
 tance from all the points of the given right 
 line. 
 
 8. A circle may be parallel to a right 
 line — that is, may be equally distant from 
 it in all its parts. 
 
 9. Right-lined triangles that are similar, 
 are also equal. 
 
 10. Of every right-lined triangle, the 
 three arg'e? taken together, are greater 
 than two right angles. 
 
 1 1. The angles of a right-lined triangle, 
 may all be right angles, or all obtuse angles. 
 
 12. Unequal circles are not as the 
 squares of their diameters, nor are their 
 circumferences in the ratio of their dia- 
 meters. 
 
 This small specimen of the geometry of 
 visibles, is intended to lead the reader to a 
 clear and distinct conception of the figure 
 and extension which is presented to the 
 mind by vision ; and to demonstrate the 
 truth of what we have affirmed above — 
 namely, that those figures and that exten- 
 sion which are the immediate objects of 
 sight, are not the figures and the extension 
 about which common geometry is employed ; 
 that the geometrician, while he looks at his 
 diagram, and demonstrates a proposition, 
 hath a figure presented to his eye, which is 
 only a sign and representative of a tangible 
 figure ; that he gives not the least atten- 
 tion to the first, but attends only to the 
 last ; and that these two figures have differ- 
 ent properties, so that what he demon- 
 strates of the one, is not true of the 
 other. 
 
 It deserves, however, to be remarked, 
 that, as a small part of a spherical surface 
 differs not sensibly from a plain surface, 
 so a small part of visible extension differs 
 very little from that extension in length 
 and breadth, which is the object of touch. 
 And it is likewise to be observed, that the 
 human eye is so formed, that an object 
 which is seen distinctly and at one view, 
 can occupy but a small part of visible space ; 
 for we never see distinctly what is at a 
 consideiable distance f,-om the axis of the 
 eye ; and, therefore, when we would see a 
 large object at one view, the eye must be 
 at so great a distance, that the object
 
 OF SEEING. 
 
 149 
 
 occupies but a small part of visible space. 
 From these two observatious, it follows, 
 that plain figures wliich are seen at one 
 view, when their planes are not oblique, but 
 direct to the eye, differ little from the 
 visible figures which they present to the 
 eye. The several lines in the tangible 
 figure, have very nearly the same propor- 
 tion to each other as in the visible ; and 
 the angles of the one are very nearly, al- 
 though not strictly and mathematically, 
 equal to those of the other. Although, 
 therefore, we have found many instances 
 of natural signs which have no similitude 
 to the things signified, this is not the case 
 with regard to visible figure. It hath, in 
 all cases, such a similitude to the thing 
 signified by it, as a plan or profile hath to that 
 which it represents ; and, in some cases, the 
 sign and thing signified have to all sense the 
 same figure and the same proportions. If 
 we could find a being endued with sight 
 only, without any other external sense, 
 and capable of reflecting and reasoning 
 upon what he sees, the notions and phi- 
 losophical speculations of such a being, 
 might assist us in the difficult task of 
 distinguishmg the perceptions which we 
 liave jiurely by siglit, from those which de- 
 rive their origin from other senses. Let 
 us suppose such a being, and conceive, 
 as well as we can, what notion he w^ould 
 have of visible objects, and what conclu- 
 sions he would deduce from them. We 
 must not conceive him disposed by his con- 
 stitution, as we are, to consider the visi- 
 ble appearance as a sign of something else : 
 it is no sign to him, because there is no- 
 thing signified by it ; and, therefore, we must 
 suppose him as much disposed to attend to 
 the visible figure and extension of bodies, 
 as we are disposed to attend to their tangi- 
 ble figure and extension. 
 
 If various figures were presented to his 
 sense, he might, without doubt, as they 
 grow familiar, compare them together, and 
 perceive wherein they agree, and wherein 
 they differ. He miglit perceive visible ob- 
 jects to have length and breadth, but could 
 have no notion of a third dimension, any 
 more than we can have of a fourth.* Atl 
 visible objects would appear to be termi- 
 nated by lines, straiglit or curve ; and ob- 
 jects terminated by the same visible lines, 
 would occupy the same place, and fill the 
 same part of visible space. It would not 
 be possible for him to conceive one object 
 to be behind another, or one to be nearer, 
 another more distant. 
 
 To us, who conceive three dimensions, a 
 line may be conceived straight ; or it may 
 be conceived incurvated in ono dimension, 
 
 ♦ ThU proceedn iipdti the siipponilion that our no- 
 tion or (pace i» intTcly ciri|iiri<'al. — II. 
 
 and straight in another ; or, lastly, it may 
 be incurvated in two dimensions. Suppose 
 a line to be drawn upwards and downwards, 
 its length makes one dimension, which we 
 shall call upwards and dnwnu-ards ; and 
 there are two dimensions remaining, accord- 
 ing to which it may be straight or curve. 
 It may be bent to the rij^ht or to the left ; 
 and, if it has no bending either to right or 
 left, it is straight in this dimension. But 
 supposing it straight in this dimension of 
 right and left, there is still another dimen- 
 sion remaining, in which it may be curve ; 
 for it may be bent backwards or forwards. 
 When we conceive a tangible straight line, 
 we exclude curvature in either of these two 
 dimensions : and as what is conceived to be 
 excluded, must be conceived, as well as 
 what is conceived to be included, it follows 
 that all the three dimensions enter into our 
 conception of a straight line. Its length 
 is one dimension, its straightness in two 
 other dimensions is included, or curvature 
 in these two dimensions excluded, in the 
 conception of it. 
 
 The being we have supposed, having no 
 conception of more than two dimensions, of 
 which the length of a line is one, cannot 
 possibly conceive it either straight or curve 
 in more than one dimension ; so that, in his 
 conception of a right line, curvature to the 
 right hand or left is excluded ; but curva- 
 ture backwards or forwards cannot be ex- 
 cluded, because he neither hath, nor can 
 have any conception of such curvature. 
 Hence we see the reason that a line, wliich 
 is straight to the eye, may return into itself ; 
 for its being straight to the eye, implies only 
 straightness in one dimension ; and a line 
 which is straight in one dimension may, 
 notwithstanding, be curve in another dimen- 
 sion, and so may return into itself. 
 
 To us, who conceive three dimensions, a 
 surface is that which hath length and 
 breadth, excluding thickness ; and a surface 
 may be either plain in this third dimension, 
 or it may be incurvated : so that the notion 
 of a third dimension enters into our concep- 
 tion of a surface ; for it is only by means 
 of this third dimension that we can dis- 
 tinguish surfaces into plain and curve sur- 
 faces ; and neither one nor the other can 
 be conceived without conceiving a third 
 dimension. 
 
 The being we liavo supposed, having no 
 conception of a third dimension, his visible 
 figures have length and breadth indeed; 
 but thickness is neither included nor ex- 
 cluded, being a thing of whieli he has no 
 concej)tion. And, therefore, visililc figures, 
 although they have length and breadtji, as 
 8iirfac(!8 have, yet tliey are neither plain 
 surfaces nor curve surfaces. For a curve 
 surface implies curvature in a tliird dinien- 
 si(in, ami a plain surface imjilics the wani
 
 150 
 
 OF THE HUMAN MIND. 
 
 of curvature in a third dimension ; and 
 such a being can conceive neither of these, 
 because he has no conception of a third 
 dimension. Moreover, although he hath a 
 distinct conception of the incluiation of two 
 lines which make an angle, yet he can 
 neither conceive a plain angle nor a spher- 
 ical angle. Even his notion of a point is 
 somewhat less determined than ours. In 
 the notion of a point, we exclude length, 
 breadth, and thickness ; he excludes length 
 and breadth, but cannot either exclude or 
 include thickness, because he hath no con- 
 ception of it. 
 
 Having thus settled the notions which 
 such a being as we have supposed might 
 form of mathematical points, lines, angles, 
 and figures, it is easy to see, that, by com- 
 paring these together, and reasoning about 
 them, he might discover their relations, and 
 form geometrical couclusions built upon 
 self-evident principles. He might likewise, 
 without doubt, have the same notions of 
 numbers as we have, and form a system of 
 arithmetic. It is not material to say in 
 what order he might proceed in such dis- 
 coveries, or how much time and pains he 
 might employ about them, but what such 
 a being, by reason and ingenuity, without 
 any materials of sensation but those of 
 sight only, might discover. 
 
 As it is more difficult to attend to a de- 
 tail of possibilities than of facts, even of 
 slender authority, I shall beg leave to give 
 an extract from the travels of Johannes 
 Rudolphus Anepigraphus, a Rosicrucian 
 philosopher, who having, by deep study of 
 the occult sciences, acquired the art of 
 transporting himself to various sublunary re- 
 gions, and of conversing with various orders 
 of intelligences, in the course of his adven- 
 tures became acquainted with an order of 
 beings exactly such as I have supposed. 
 
 How they communicate their sentiments 
 to one another, and by what means he be- 
 came acquainted with their language, and 
 was initiated into their philosophy, as well 
 as of many other particulars, which might 
 have gratified the curiosity of his readers, 
 and, perhaps, added credibility to his rela- 
 tion, he hath not thought fit to inform us ; 
 f'sse being matters proper for adepts only 
 W know. 
 
 His account of their philosophy is as fol- 
 lows : — 
 
 " The Idomenians," saith he, "are many 
 of them very ingenious, and much given to 
 contemplation. In arithmetic, geometry, 
 metaphysics, and physics, tlicy have most 
 elaborate systems. In the two latter, in- 
 deed, they have had many disputes carried 
 on with great subtilty, and are divided in- 
 to various sects ; yet in the two former 
 there hath been no less UTianimity than 
 among the human species. Their princi- 
 
 ples relating to immbers and arithmetic, 
 making allowance for their notation, diflTer 
 in nothing from ours — but their geometry 
 difl'ers very considerably." 
 
 As our author's account of the geometry 
 of the Idomenians agrees in everything 
 with the geometry of visibles, of which we 
 have already given a specimen, we shall 
 pass over it. He goes on thus : — " Colour, 
 extension, and figure, are conceived to be 
 the essential properties of body. A very 
 considerable sect maintains, that colour is 
 the essence of body. If there had been no 
 colour, say they, there had been no percep- 
 tion or sensation. Colour is all that we 
 perceive, or can conceive, that is peculiar 
 to body ; extension and figure being modes 
 common to body and to empty space. And 
 if we should suppose a body to be annihi- 
 lated, colour is the only thing in it that can 
 be annihilated ; for its place, and conse- 
 quently the figure and extension of that 
 place, must remain, and cannot be imagined 
 not to exist. These philosophers hold space 
 to be the place of all bodies, immoveable and 
 indestructible, without figure, and similar 
 in all its parts, incapable of increase or di- 
 minution, yet not unmeasurable ; for every 
 the least part of space bears a finite ratio to 
 the whole. So that with them the whole 
 extent of space is the common and natural 
 measure of everything that hath length and 
 breadth ; and the magnitude of every body 
 and of every figure is expressed by its being 
 such a part of the universe. In like manner, 
 the common and natural measure of length 
 is an infinite right line, which, as hath been 
 before observed, returns into itself, and hath 
 no limits, but bears a finite ralio to every 
 other line. 
 
 " As to their natural philosophy, it is 
 now acknowledged by the wisest of them to 
 have been for many ages in a very low 
 state. The philosophers observing, that 
 body can differ from another only in colour, 
 figure, or magnitude, it was taken for 
 granted, that all their particular qualities 
 must arise from the various combinations 
 of these their essential attributes ; and, 
 therefore, it was looked upon as the end of 
 natural philosophy, to shew how the various 
 combinations of these three qualities in dif- 
 ferent bodies produced all the phsenomena 
 of nature. It were endless to enumerate 
 the various systems that were invented with 
 this view, and the disputes that were car- 
 ried on for ages ; the followers of every 
 system exposing the weak sides of other 
 systems, and palliating those of their own, 
 with great art. 
 
 " At last, some free and facetious spirits, 
 wearied with eternal disputation, and the 
 labour of patching and propping weak sys- 
 tems, began to complain of the subtilty of 
 nature ; of the infinite changes that bodies
 
 OF SEEING. 
 
 151 
 
 ondergo iu figure, colour, and magnitude ; 
 and of the difficulty of accounting for these 
 appearances — making this a pretence for 
 giving up all inquiries iuto the causes of 
 things, as vain and fruitless. 
 
 " These wits had ample matter of mirth 
 and ridicule in the systems of philosophers ; 
 and, linduig it an easier task to pull down 
 than to build or support, and that every 
 sect furnished them with arms and auxi- 
 liaries to destroy another, they began to 
 spread mightily, and went on with great 
 success. Thus philosophy gave way to scep- 
 ticism and irony, and those systems which 
 had been the work of ages, and the admira- 
 tion of the learned, became the jest of the 
 vulgar : for even the vulgar readily took 
 part in the triumph over a kind of learning 
 whicli they had long suspected, because it 
 produced nothing but wrangling and alter- 
 cation. The wits, having now acquired great 
 reputation, and being flushed with success, 
 began to think their triumph incomplete, 
 until every pretence to knowledge was over- 
 turned; and accordingly began their attacks 
 upon arithmetic, geometry, and even upon 
 the common notions of untaught Idomen- 
 ians. So difficult it hath always been," says 
 our author, " for great conquerors to know 
 where to stop. 
 
 " In the meantime, natural philosophy 
 began to rise from its ashes, under the 
 direction of a person of great genius, wlio is 
 looked upon as having had something in him 
 above Idomenian nature. He observed, 
 that the Idouieuian faculties were certainly 
 iutended for contemplation, and that the 
 works of nature were a nobler subject to 
 exercise them upon, than the follies of sys- 
 tems, or the errors of the learned ; and 
 being sensible of the difficulty of finding out 
 the causes of natural things, he proposed, 
 by accurate observation of tlie jihteiioniena 
 {ji nature, to find out the rules according to 
 which they happen, without inquiring into 
 the causes of those rules. In this lie made 
 considerable progress himself, and planned 
 out much work for liLs followers, who call 
 themselves inductive philosophers. The 
 sceptics look with envy upon this rising 
 eect^ as eclipsing their rej)utation, and 
 threatening to limit their empire ; but they 
 are at a loss on what hand to attack it. 
 The vulgar begin to reverence it as pro- 
 ducing useful discoveries. 
 
 " It is to be observed, that evei-y Idome- 
 nian firmly believes, that two or more bo- 
 dies may exist in the same place. For Ibis 
 they have the testimony of sense, and they 
 can no more doubt of it, than they can 
 doubt whether they have any perception at 
 all. They often see two bodies meet and 
 coincide in the same place, and separate 
 again, without having undergone any 
 change in their hcnsible qualities by thlH 
 
 penetration. When two bodies meet, and 
 occupy the same place, commonly one only 
 appears in that place, and the other disap- 
 pears. That which continues to appear is 
 said to overcome, the other to be over- 
 come." 
 
 To this quality of bodies they gave a 
 name, which our author tells us hath no 
 word answering to it in any human lan- 
 guage. And, therefore, after makmg a 
 long apology, which I omit, he begs leave 
 to call it the overcoming quality of bodies. 
 He assures us, that "the speculatious which 
 had been raised about this single quality of 
 bodies, and the hypotheses contrived to ac- 
 count for it, were sufficient to fill many 
 volumes. Nor have there been fewer hy- 
 potheses invented by their philosophers, to 
 account for the changes of magnitude and 
 figure ; which, in most bodies that move, 
 they perceive to be in a continual fluctua- 
 ation. The founder of the inductive sect, 
 believing it to be above the reach of Ido- 
 menian faculties, to discover the real causes 
 of these phsenomena, applied himself to 
 find from observation, by what laws they 
 are connected together ; and discovered 
 many mathematical ratios and relations con- 
 cerning the motions, magnitudes, figures, 
 and overcoming quality of bodies, which 
 constant experience confirms. But the op- 
 posers of this sect choose rather to content 
 themselves with feigned causes of these 
 phsenomena, than to acknowledge the real 
 laws whereby they are governed, which 
 humble their pride, by bemg confessedly 
 unaccountable." 
 
 Thus far Johannes Rudolphus Anepigra- 
 ]ihus. Whether this Anepigraphus be the 
 same who is recorded among the Greek 
 alchemistical writers not yet published, by 
 Borrichius, Fabricius, and others," I do 
 not pretend to determine. The identity of 
 their name, and the similitude of their 
 studies, although no slight arguments, yet 
 are not absolutely conclusive. Nor will I 
 take upon me to judge of the narrative of 
 this learned traveller, by the iwicrnal marks 
 of his credibility ; 1 shall confine myself to 
 those which the crit cs call internal. It 
 would even be of small importance to in- 
 quire, whether the Idonunians have a real, 
 or only an ideal existence ; since this is 
 disputed among the learned with regard to 
 things with which we are more nearly con- 
 nected. The hnportant question is, wlie- 
 ther the account above given, is a just ac- 
 count of their geometry and philosophy ? 
 We have all the faculties which they 
 
 » This is true ; tlic namr is not imaginary 
 "Anc|)i(!ra;)hHKll)criul<)Sc)i)liir''isllieioinitO(liUitli<)r 
 ol Sfver.il rlK iiii( nl treating in (irii-k, wliicli have not 
 .16 yet berii cli I'liieil worthy of i)iihlicnti(>ii. Sec 
 Oil Cniigc, " Glo8«. mcil. I't inf.. (JraicilntiB," voce 
 Umr.Ti.t, and Keiiifsii, " Viir. licit" I.. II. c. 5. 
 — II.
 
 J 52 
 
 OF THE- HUMAN MIND. 
 
 have, with the addition of others which 
 they have not ; we may, therefore, form 
 some judgment of their philosophy and ge- 
 ometry, by separating from all others, the 
 perceptions we have by sight and reasoning 
 upon them. As far as I am able to judge 
 in this way, after a careful examination, their 
 geometry must be such as Anepigraphus 
 hath described. Nor does his account of 
 their philosophy appear to contain any evi- 
 dent marlvs of imposture ; although here, 
 no doubt, proper allowance is to be made 
 for liberties which travellers take, as well as 
 for involuntary mistakes which they are apt 
 to fall into. 
 
 Section X. 
 
 OF THE PARALLEL MOTION OF THE EYES. 
 
 Having explained, as distinctly as we 
 can, visible figure, and shewn its connection 
 with the things signified by it, it will be 
 proper next to consider some phsenomena 
 of the eyes, and of vision, which have com- 
 monly been referred to custom, to anato- 
 mical or to mechanical causes ; but which, 
 as I conceive, must be resolved into origi- 
 nal powers and principles of the human mind ; 
 and, therefore, belong properly to the sub- 
 ject of this inquiry. 
 
 The first is the parallel motion of the 
 eyes ; by which, when one eye is turned 
 to the right or to the left, upwards or down- 
 wards, or straight forwards, the other 
 always goes along with it in the same direc- 
 tion. We see plainly, when both eyes are 
 open, that they are always turned the same 
 way, as if both were acted upon by the same 
 motive force ; and if one eye is shut, and the 
 hand laid upon it, whi'e the other turns 
 various ways, we feel the eye that is shut 
 turn at the same time, and that whether 
 we will or not. What makes this phteno- 
 menon surprising is, that it is acluiowledged, 
 by all anatomists, that the muscles which 
 move the two eyes, and the nerves which 
 serve these muscles, are entirely distinct 
 and unconnected. It would be thought 
 very surprising and unaccountable to see a 
 man, who, from his birth, never moved 
 one arm, without moving the other pre- 
 cisely in the same manner, so as to keep 
 them always parallel— yet it would not be 
 more difficult to find the physical cause of 
 such motion of the arms, than it is to find 
 the cause of the parallel motion of the eyes, 
 which is perfectly similar. 
 
 The only cause that hath been assigned 
 of this parallel motion of the eyes, is cus- 
 tom. We find by experience, it is said. 
 when we begin to look at objects, that, in 
 order to have distinct vision, it is necessary 
 to turn both eyes the same way ; therefore. 
 
 we soon acquire the habit of doing it con- 
 stantly, and by degrees lose the power of 
 doing otherwise. 
 
 This account of the matter seems to be 
 insufficient ; because habits are not got at 
 once ; it takes time to acquire and to con- 
 firm them ; and if this motion of the eyes 
 were got by habit, we should see children, 
 when they are born, turn their eyes difierent 
 ways, and move one without the other, as 
 they do their hands or legs. I know some 
 have affirmed that they are apt to do so. 
 But I have never found it true from my 
 own observation, although I have taken 
 pains to make observations of this kind, and 
 have had good opportunities. I have 
 hkewise consulted experienced inidwives, 
 mothers, and nurses, and found them agree, 
 that they had never observed distortions 
 of this kind in the eyes of children, but 
 when they had reason to suspect convul- 
 sions, or some preternatural cause. 
 
 It seems, therefore, to be extremely pro- 
 bable, that, previous to custom, there is 
 something in the constitution, some natural 
 instinct, which directs us to move both eyes 
 always the same way.* 
 
 We know not how the mind acts upon 
 the body, nor by what power the muscles 
 are contracted and relaxed — but we see 
 that, in some of the voluntary, as well as 
 in some of the involuntary motions, this 
 power is so directed, that many muscles 
 which have no material tie or connection, -f 
 act in concert, each of them being taught 
 to play its part in exact time and measure. 
 Nor doth a company of expert players in 
 a theatrical performance, or of excellent 
 musicians in a concert, or of good dancers 
 in a country dance, with more regularity 
 and order, conspire and contribute their 
 several parts, to produce one uniform effect, 
 than a number of muscles do, in many of 
 the animal functii ns, and in many volun- 
 tary actions. Yet we see such actions no 
 less skilfully and regularly performed in 
 children, and in those who know not that 
 they have such muscles, than in the most 
 skilful anatomist and physiologist. 
 
 Who taught all the muscles that are 
 concerned in sucking, in swallowing our 
 food, in breathing, and in the several na- 
 tural expulsions, to act their part in such 
 regular order and exact measure ? It was 
 not custom surely. It was that same power- 
 ful and wise Being who made the faljric of 
 the human body, and fixed the laws by 
 which the mind operates upon every part 
 
 • The parallel movemrnt, like other reciprocities 
 of the two eyes, can be explained physiologiialli;, 
 liy the "mutiial relatior. of their nerves, withcjut rr. 
 ciirring to any higher or moremvsterious principle. — 
 H. 
 
 t This is nut correct. Muscles which have cor. 
 relative niotioiis are now either known or admitted 
 to tiavc correlative nerves — H.
 
 OF SEEING. 
 
 153 
 
 of it, so that they may answer the pur- 
 poses intended by them. And when we 
 see, in so many other instances, a system 
 of unconnected muscles* conspiring so won- 
 derfully in their several functions, without 
 the aid" of habit, it needs not be thought 
 strange, that the nmscles of the eyes should, 
 without this aid, conspire to give that di- 
 rection to the eyes, without which they 
 could not answer their end. 
 
 We see a like conspiring action in the 
 muscles which contract the pupils of the 
 two eyes ; and in those muscles, whatever 
 they be, by which the conformation of the 
 eyes is varied according to tlie distance of 
 objects- 
 
 It ought, however, to be observed, that, 
 although it appears to be by natural in- 
 stinct that both eyes are always turned 
 the same way, there is still some latitude 
 left for custom. 
 
 What we have said of the parallel motion 
 of theeyes, is not to be understood so strictly 
 as if nature directed us to keep their axes 
 always precisely and mathematically par- 
 allel to each other. Indeed, although they 
 are always nearly parallel, they hardly ever 
 are exactly so. When we look at an ob- 
 ject, the axes of the eyes meet in that 
 object : and, therefore, make an angle, which 
 is always small, but will be greater or less, 
 according as the object is nearer or more 
 remote. Nature hath very wisely left us 
 the power of varying the parallelism of our 
 eyes a little, so that we can direct them to 
 the same point, whether remote or near. 
 This, no doubt, is learned by custom ; and 
 accordingly we see, that it is a long time 
 before children get this habit in perfection. 
 
 This power of varying the parallelism of 
 theeyes is naturally no more than is suffi- 
 cient for the purpose intended by it ; but 
 by much practice and straining, it may be 
 increased. Accordingly, we see, that some 
 have acquired the power of distorting their 
 eyes into unnatural directions, as others 
 have acquired the power of distorting their 
 bodies into unnatural postures. 
 
 Those who have lost the sight of an eye, 
 commonly lose what they had got by custom, 
 in the direction of their eyes, but retain 
 what they had by nature ; that is, although 
 their eyes turn and move always together, 
 yet, when they look u]ion an object, the 
 blind eye will often have a very small devia- 
 tion from it ; wliicli is not perceived by a 
 elight obierver, but may be discerned by 
 one accustomed to make exact observations 
 in tliese matters. 
 
 See the prcctdiDg iiotc. 
 
 Seclion XI. 
 
 OF OUR SEEING OliJECTS ERECT BY INVERTED 
 IMAGES. 
 
 Another phrcnomenon which hath per- 
 plexed philosophers, is, our seeing objects 
 erect, when it is well known that their 
 images or pictures upou the tunica retina 
 of the eye are inverted. 
 
 The sagacious Kepler first made the 
 noble discovery, that distinct but inverted 
 pictures of visible objects ar^ formed upon 
 the ritina by the rays of light coming from 
 the object. The same great philosopher 
 demonstrated, from the principles of optics, 
 how these pictures are formed — to wit, 
 That the rays coming from any one point 
 of the object, and falling upon the various 
 parts of the pupil, are, by the cornea and 
 crystalline, refracted so as to meet again 
 in one point of the retina, and there paint 
 the colour of that point of the object from 
 which they come. As the rays from dif- 
 ferent points of the object cross each other 
 before they come to the retina, the picture 
 they form must be inverted ; the upper 
 part of the object being painted upon the 
 lower part of the retina, the right side of 
 the object upon the left of the retina, and 
 so of the other parts.* 
 
 This philosopher thought that we see 
 objects erect by means of these inverted 
 pictures, for this reason, that, as the rays 
 from diflerent points of the object cross 
 each other before they fall upon the letina, 
 we conclude that the impulse which we feel 
 upon the lower part of the retina comes 
 from above, and that the impulse which 
 we feel upon the higher part comes from 
 below. 
 
 Des Cartes afterwards gave the same 
 solution of this phenomenon, and illustrated 
 it by the judgment which we form of the 
 position of objects which we feel with our 
 arms crossed, or with two-sticks that cross 
 each other. 
 
 liut we cannot acquiesce in this solution. 
 First, Because it supposes our seeing things 
 erect, to be a deduction of reason, drawn from 
 certain premises : whereas it seems to be an 
 immediate perception. And, secondly. Be- 
 cause the premises from which all mankind 
 are supposed to draw this conclusion, never 
 entered into the minds of the far greater 
 part, but are absolutely unknown to them. 
 We have no feeling or perception of the 
 pictures upon the retina, and as little surely 
 
 * This inverted picture is seen it" we take the oyc 
 ot an iix. lor (x:ini|ili-, iinil cut auay the posicrmr 
 p:iit ot llic sclerotica hikI choroid; l)Ut, williovit Ilit-t 
 preparation, it is apparent m thr eyes ol all) no am 
 inals, of llieowl, fie, in winch Ihf tintd ivnr and 
 ilioiuid are scini. diaphanous. — li.
 
 154 
 
 OF THE HUMAN MIND 
 
 of the position of them. In order to see I 
 objects erect, according to the princii)les 
 of Kepler or Des Cartes, we must previ- 
 ously know that the rays of light come 
 from the object to the eye in straight lines ; 
 we must know that the rays from different 
 points of the object cross one another 
 before they form the pictures upon the 
 retina ; and, lastly, we must know that these 
 pictures are really inverted. Now, although 
 all these things are true, and known to 
 philosophers, yet they are absolutely un- 
 known to the far greatest part of mankind : 
 nor is it possible that they who are abso- 
 lutely ignorant of them, should reason from 
 them, and build conclusions upon them. 
 Since, therefore, visible objects appear erect 
 to the ignorant as well as to the learned, 
 this cannot be a conclusion drawn from 
 premises which never entered into the minds 
 of the ignorant. We have indeed had oc- 
 casion to observe many instances of con- 
 clusions drawn, either by means of original 
 principles, or by habit, from premises which 
 pass through the mind very quickly, and 
 which are never made the objects of re- 
 flection ; but surely no man will conceive 
 it possible to draw conclusions fro n pre- 
 mises which never entered into the mind at 
 all. 
 
 Bishop Berkeley having justly rejected 
 this solution, gives one founded upon his 
 own principles ; wherein he is followed by 
 the judicious Dr Smith, in his " Optics;" 
 and this we shall next explain and examine. 
 That ingenious writer conceives the ideas 
 of sight to be altogether unlike those of 
 touch. And, since the notions we have of 
 an object by these different senses have no 
 similitude, we can learn only by experience 
 how one sense will be affected, by what, in 
 a certain manner, affects the other. Figure, 
 position, and even number, in tangible 
 objects, are ideas of touch ; and, although 
 there is no similitude between these and 
 the ideas of sight, yet we learn by expe- 
 rience, that a triangle affects the sight in 
 such a manner, and that a square affects it 
 in such another manner — hence we judge 
 that which affects it in the first manner, to 
 be a triangle, and that which affects it in 
 the second, to be a square. In the same 
 way, finding, from experience, that an object 
 in an erect position affects the eye in one 
 manner, and the same object in an inverted 
 position affects it in another, we learn to 
 judge, by the manner in which the eye is 
 affected, whether the object is erect or in- 
 verted. In a word, visible ideas, according 
 to this author, are signs of the tangible ; 
 and the mind passeth from the sign to th.e 
 thing signified, not by means of any simi- 
 litude between the one and other, nor by 
 any natural principle, but by having found 
 them constantly conjoined in experience, as 
 
 the sounds of a language are with the things 
 they signify : so that, if the images upon 
 the retina had been always erect, they 
 would have shewn the objects erect, in the 
 manner as they do now that they are in- 
 verted — nay, if the visible idea which we 
 now have from an inverted object, had been 
 associated from the beginning with the erect 
 position of that object, it would have signi- 
 fied an erect position, as readily as it now 
 signifies an inverted one. And, if the vis- 
 ible appearance of two shillings had been 
 found connected from the beginning with 
 the tangible idea of one shilling, that ap- 
 pearance would as naturally and readily 
 have signified the unity of the object as now 
 it signifies its duplicity. 
 
 This opinion is, undoubtedly, very inge- 
 liious ; and, if it is just, serves to resolve 
 not only the pha;nomenon now under con- 
 sideration, but likewise that which we shall 
 next consider — our seeing objects single 
 with two eyes. 
 
 It is evident that, in this solution, it is 
 supposed that we do not originally, and 
 previous to acquired habits, see things 
 either erect or inverted, of one figure or 
 another, single or double ; but learn, from 
 experience, to judge of their tangible posi- 
 tion, figure, and number, by certain visible 
 signs. 
 
 Indeed, it must be acknowledged to be 
 extremely difficult to distinguish the imme- 
 diate and natural objects of sight, from 
 the conclusions which we have been ac- 
 customed from infancy to draw from them. 
 Bishop Berkeley was the first that attem.pted 
 to distinguish the one from the other, and 
 to trace out the boundary that divides them. 
 And if, in doing so, he hath gone a little to 
 the right hand or to the left, this might be 
 exjiected in a subject altogether new, and 
 of the greatest subtilty. The nature of 
 vision hath received great light from this 
 distinction ; and many phsenomena in 
 optics, which before appeared altogether 
 unaccountable, have been clearly and dis- 
 tinctly resolved by it. It is natural, and 
 almost unavoidable, to one who hath made 
 an important discovery in philosophy, to 
 carry it a little beyond its sphere, and to 
 apply it to the resolution of phsenomena 
 which do not fall within its province. Even 
 the great Newton, when he had discovered 
 the universal law of gravitation, and ob- 
 served how many of the phsenomena of 
 nature depend upon this, and other laws of 
 attraction and repulsion, could not help ex- 
 pressing his conjecture, that all the phseno- 
 mena of the material world depend upon 
 attracting and repelling forces in the par- 
 ticles of matter. And I suspect that the 
 ingenious Bishop of Cloyne, having found 
 so many phsenomena of vision reducible to 
 the constant association of the ideas of sight
 
 OF SEEING. 
 
 155 
 
 and touch, carried this principle a little be- 
 yond its just limits. 
 
 In order to judge as well as we can 
 whether it is so, let us suppose such a blind 
 man as Dr Saunderson, having all the 
 knowledge and abilities which a blind man 
 may have, suddenly made to see perfectly. 
 Let us suppose him kept from all opportu- 
 nities of associating his ideas of sight with 
 those of touch, until the former become a 
 httle fumiliar ; and the first surprise, occa- 
 sioned by objects so new, being abated, he 
 has time to canvass them, and to compare 
 them, in his mind, with the notions which 
 he formerly had by touch ; and, in particu- 
 lar, to compare, in his mind, that visible 
 extension which his eyes present, with the 
 extension in length and breadth with which 
 he was before acquainted. 
 
 We have endeavoured to prove, that a 
 blind man may form a notion of the visible 
 extension and figure of bodies, from the 
 relation which it bears to their tangible 
 extension and figure. Much more, when this 
 visible extension and figure are presented 
 to his eye, will he be able to compare them 
 with tangible extension and figure, and to 
 perceive that the one has length and breadth 
 as well as the other ; that the one may be 
 bounded by lines, either straight or curve, 
 as well as the other. And, therefore, he 
 will perceive that there may be visible as 
 well as tangible circles, triangles, quadri- 
 lateral and multilateral figures. And, al- 
 though the visible figure is coloured, and 
 the tangible is not, they may, notwithstand- 
 ing, have the same figure ; as two objects 
 of touch may have the same figure, although 
 one is hot and the other cold. 
 
 We have demonstrated, that the proper- 
 ties of visible figures differ from those of 
 the j)laiu figures which they represent ; but 
 it was observed, at the same time, that 
 when the object is so small as to be seen 
 distinctly at one view, and is jjlaced directly 
 before the eye, the difference between the 
 visible and the tangible figure is too small 
 to be perceived by the senses. Thus, it is 
 true, that, of every visible triangle, the 
 three angles are greater than two right 
 angles ; whereas, in a plain triangle, the 
 three angles arc equal to two right angles ; 
 but when the visible triangle is small, its 
 three angles will be so nearly equal to two 
 right angles, that the sense cannot discern 
 the ditt'erence. In like manner, the circum- 
 ferences of unequal visible circles are not, 
 K)ut those of plain circles are, in the ratio of 
 their diameters ; yet, in small visible circles, 
 the circumferences are very nearly in the 
 rn/io of their diameters ; and the diameter 
 bears the same rutin to the circumference, 
 as in a jdaiu circle, very nearly. 
 
 Hence it appears, that small viRibl<! 
 figures (and such only can be seen distinctly 
 
 at one view) have not only a resemblance 
 to the plain tangible figures which have the 
 name name, but are to all sense the same : 
 so that, if Dr Saunderson had been made to 
 see, and had attentively viewed the figures 
 of the first book of Euclid, he might, by 
 thought and consideration, without touching 
 them, have found out that they were the 
 very figures he was before so well ac- 
 quainted with by touch. 
 
 When plain figures are seen obliquely, 
 their visible figure differs more from the 
 tangible ; and the representation which is 
 made to the eye, of solid figures, is still 
 more imperfect ; because visible extension 
 hath not three, but two dimensions only. 
 Yet, as it cnnnot be said that an exact pic- 
 ture of a man hath no resemblance of the 
 man, or that a perspective view of a house 
 hath no resemblance of the house, so it 
 cannot be said, with any propriety, that the 
 visible figure of a man or of a house hath 
 no resemblance of the objects which they 
 represent. 
 
 Bishop Berkeley therefore proceeds upon 
 a capital mistake, in supposing that there is 
 no resemblance betwixt the extension, figure, 
 and position which we see, and that which 
 we perceive by touch. 
 
 We may further observe, that Bishop 
 Berkeley's system, with regard to material 
 things, must have made him see this ques- 
 tion, of the erect appearance of objects, in 
 a very different light from that in which it ap- 
 pears to those who do not adopt his system. 
 
 In his theory of vision, he seems indeed 
 to allow, that there is an external material 
 world : but he believed that this external 
 world is tangible only, and not visible ; and 
 that the visible world, the proper object of 
 sight, is not external, but in the mind. If 
 this is supposed, he that affirms that he 
 sees things erect and not inverted, affirms 
 that there is a top and a bottom, a right 
 and a left in the mind. Now, I confess I 
 am not so well acquainted with the topo- 
 grajihy of the mmd, as to be able to affix 
 a meaning to these words when applied 
 to it. 
 
 \Ve shall therefore allow, that, if visible 
 objects were not external, but existed only 
 in the mind, they could have no figure, or 
 position, or extension ; and that it would be 
 absurd to affirm, that they arc seen cither 
 erect or inverted, or that there is any re- 
 semblance between them and the objects of 
 touch. But when we propose the question, 
 why objects are seen erect and not in- 
 verted, we take it for granted, that we are 
 not in Bishop Berkeley's ideal world, but 
 in that world which men who yield to the 
 dictates of connnon sense, believe them- 
 selves to inhabit. We take it f(tr granted, 
 that the objects both of sight and touch, 
 arc external, and have a certain figure, and
 
 156 
 
 OF THE HUMAN MIND. 
 
 a certain position with regard to one another, 
 and with regard to our bodies, whether we 
 perceive it or not. 
 
 When I hold my walking-cane upright 
 in my hand, and look at it, I take it for 
 granted that I see and handle the same 
 individual object. When I say that I feel 
 it erect, my meaning is, that I feel the 
 head directed from the horizon, and the 
 point directed towards it ; and when I say 
 that I see it erect, I mean that I see it with 
 the head directed from the horizon, and 
 the point towards it. I conceive the hori- 
 zon as a fixed object both of sight and touch, 
 with relation to which, objects are said to 
 be high or low, erect or inverted ; and when 
 the question is asked, why I see the ob- 
 ject erect, and not inverted, it is the same 
 as if you should ask, why I see it in that 
 position which it really hath, or why the 
 eye shews the real position of objects, and 
 doth not shew them in an inverted posi- 
 tion, as they are seen by a common astro- 
 nomical telescope, or as their pictures are 
 seen upon the retina of an eye when it is 
 dissected. 
 
 Seclion XII. 
 
 THE SAME SUBJECT CONTINUED. 
 
 It is impossible to give a satisfactory an- 
 swer to this question, otherwise than by 
 pointing out the laws of nature which take 
 place in vision ; for by these the phaeno- 
 mena of vision must be regulated. 
 
 Therefore, I answer, First, That, by a 
 law of nature, the rays of light proceed from 
 every point of the object to the pupil of 
 the eye, in straight lines ; Secondly, That, 
 by the laws of nature, the rays coming 
 from any one point of the object to the va- 
 rious parts of the pupil, are so refracted as 
 to meet again in one point of the retina ; 
 aud the rays from different points of the 
 object, first crossing each other,* and then 
 proceeding to as many different points of 
 the retina, form an inverted picture of the 
 object. 
 
 So far the principles of optics carry 
 us ; and experience further assures us, that, 
 if there is no such picture upon the retina, 
 there is no vision ; and that such as the 
 picture on the retina is, such is the appear- 
 
 » It is marvellous how widely both natur 1 philo- 
 sophers and physiologists are at variance with regard 
 to the pnint of the eTe at which the rays cro.-s each 
 other. Some place this point in the cornea — some 
 in the region of the pupil— some in the centre of the 
 crystalline — and some in the vitreous humour. 
 Recent experiments, instituted for the purpose of 
 determining its locality, and still unknown in this 
 country, place it behind the crystalline lens. This 
 is found to be at once the crossing pnint, both of the 
 rays of light and of the line of vi.^ible direction, and 
 the turning point on which the eye rolls.— H. 
 
 ance of the object, in colour and figure, 
 distinctness or indistinctness, brightness or 
 faintness. 
 
 It is evident, therefore, that the pictures 
 upon the retina are, by the laws of nature, 
 a mean of vision ; but in what way they 
 accomplish their end, we are totally igno- 
 rant. Philosophers conceive, that the im- 
 pression made on the retina by the rays of 
 light, is communicated to the optic nerve, 
 and by the optic nerve conveyed to some 
 part of the brain, by them called the senso- 
 rium ; and that the impression thus conveyed 
 to the sensorium is immediately perceived 
 by the mind, which is supposed to reside 
 there. But we know nothing of the seat of 
 the soul : and we are so far from perceiving 
 immediately what is transacted in the brain, 
 that of all parts of the human body we know 
 least about it. It is indeed very probable, 
 that the optic nerve is an instrument of 
 vision no less necessary than the retina ; 
 and that some impression is made upon it, 
 by means of the pictures on the retina. 
 But of what kind this impression is, we know 
 nothing. 
 
 There is not the least probability that 
 there is any picture or image of the ob- 
 ject either in the optic nerve or brain. 
 The pictures on the retina are formed by 
 the rays of light ; and, whether we suppose, 
 with some, that their impulse upon the re- 
 tina causes some vibration of the fibres of 
 the optic nerve, or, with others, that it 
 gives motion to some subtile fluid contained 
 in the nerve, neither that vibration nor 
 this motion can resemble the visible ob- 
 ject which is presented to the mind. Nor 
 is there any probability that the mind per- 
 ceives the pictures upon the retina. These 
 pictures are no more objects of our percep- 
 tion, than the brain is, or the optic nerve. 
 No man ever saw the pictures in his own 
 eye, nor indeed the pictures in the eye 
 of another, until it was taken out of the 
 head and duly prepared. 
 
 It is very strange, that philosophers, of 
 all ages, should have agreed in this notion, 
 that the images of external objects are con- 
 veyed by the organs of sense to the brain, 
 and are there perceived by the mind.* 
 Nothing can be more unphilosophical. For, 
 First, This notion hath no foundation in fact 
 and observation. Of all the organs of 
 sense, the eye only, as far as we can disco- 
 ver, forms any kind of image of its object ; 
 and the images formed by the eye are not 
 in the brain, but only in the bottom of the 
 eye ; nor are they at all perceived or felt 
 by the miud.f Secondly, It is as difficult 
 
 * This statement in its unqualified universality ig 
 altogether erroneous. — H. 
 
 t This would require a second eye behind the 
 yclmn ; which eye would also see the images bent.
 
 OF SEEING. 
 
 157 
 
 to conceive how the mind perceives images 
 in the brain, as how it perceives things 
 more distant. If any man will shew how 
 tile mind may perceive images in the brain, 
 I will undertake to shew liow it may per- 
 ceive the most distant objects ; lor, if we 
 give eyes to the mind, to perceive what is 
 transacted at home in its dark chamber, 
 why may we not make these eyes a little 
 longer-sighted ? and then we shall have no 
 occasion for that unphilosophical fiction of 
 images in the brain. In a word, the man- 
 ner and mechanism of the mind's percep- 
 tion is quite beyond our comprehension ; 
 and this way of explaining it, by images in 
 the brain, seems to be founded upon very 
 gross notions of the mind and its opera- 
 tions ; as if the supposed images in the 
 brain, by a kind of contact, formed similar 
 impressions or images of objects upon the 
 mind, of which impressions it is supposed to 
 be conscious. 
 
 We have endeavoured to shew, through- 
 out the course of this inquiry, that the im- 
 pressions made upon the mind by means of 
 the five senses, have not the least resem- 
 blance to the objects of sense ; and, there- 
 fore, as we see no shadow of evidence that 
 there are any such images in the brain, so 
 we see no purpose, in philosophy, that tlie 
 supposition of them can answer. Since the 
 picture upon the retina, therefore, is neither 
 itself seen b^' the mind, nor produces any 
 impression upon the brain or sensorium, 
 which is seen by the mind, nor makes any 
 impression upon the mind that resembles 
 the object, it may still be asked, How this 
 picture upon the retina causes vision ? 
 
 Before we answer this question, it is pro- 
 per to observe, that, in the operations of the 
 mind, as well as in those of bodies, we must 
 often be satisfied with knowing that cer- 
 tain things are connected, and invariably 
 follow one another, without being able to 
 discover the chain that goes between them. 
 It is to such connections that we give the 
 numo oi fa ws of nature ; and when we say 
 that one thing produces another by a law 
 of nature, this signifies no more, but that 
 one thing, which we call in poj)ular lan- 
 guage the cause, is constantly and invari- 
 ably followed by another, which we call the 
 effect ; and that we know not how they are 
 connected. Thus, we see it is a fact, that 
 bodies gravitate towards bodies ; and that 
 this gravitation is regulated by certain 
 mathematical proportions, according to the 
 distances of the bodies from each other, 
 and their quantities of matter. Being un- 
 able to discover the cause of this gravita- 
 tion, and presuming that it is tin; immediate 
 oi)eration, either of the Author of nature, 
 
 n« thpy are pictured on the concavity of that mem- 
 brane — H. 
 
 or of some subordinate cause, which we 
 have not hitherto been able to reach, we 
 call it a law of nature. If any philoso- 
 pher should hereafter be so happy as to 
 discover the cause of gravitation, this can 
 only be done by discovering some more 
 general law of nature, of which the gravi- 
 tation of bodies is a necessary consequence. 
 In every chain of natural causes, the highest 
 link is a primary law of nature, and the 
 highest link which we can trace, by just 
 mduction, is either this primary law of 
 nature, or a necessary consequence of it. 
 To trace out the laws of nature, by induc- 
 tion from the phaiuomena of nature, is all 
 that true philosophy aims at, and all that it 
 can ever reach. 
 
 There are laws of nature by which the 
 operations of the muid are regulated, there 
 are also laws of nature that govern the 
 material system ; and, as the latter are tlie 
 ultimate conclusions which the human 
 faculties can reach in the philosophy of 
 bodies, so the former are the ultimate con- 
 clusions we can reach in the philosophy of 
 minds. 
 
 To return, therefore, to the question 
 above proposed, we may see, from what 
 hath been just now observed, that it 
 amounts to this — By what law of nature is 
 a picture upon the retina the mean or 
 occasion of my seehig an external object of 
 the same figure and colour in a contrary 
 position, and in a certain direction from the 
 eye ? 
 
 It wUl, without doubt, be allowed that 
 I see the whole object in the same manner 
 and by the same law by which I see any 
 one point of it. Now, I know it to be a 
 fact, that, in direct vision, I see every point 
 of the object in the direction of the right line 
 that passeth from the centre of the eye to 
 that point of the object. And I know, 
 likewise, from optics, that the ray of 
 light that comes to the centre of my 
 eye, passes on to the retina in the same 
 direction. Hence, it appears to be a iact, 
 that every poi7it of the o/ijecl is seen in the 
 direction of a riylU line passing from the 
 picture of that point on the retina, tlitouyh 
 tlie centre of the eye. As this is a fact that 
 holds universally and invariably, it must 
 either be a law of nature, or the necessary 
 consequence of some more general law of 
 nature ; and, according to the just rules of 
 philosophising, we may hold it for a law of 
 nature, until some more general law be 
 discovered, whereof it is a necessary conse- 
 quence — which, I suspect, cau never be 
 done." 
 
 ♦ A confirmation of tliis doctrine is drawn from 
 • he cases of (lieseldeii and iithrr.s, in which no nieii- 
 t.il Inversion of the ol)jectH is nutic(sl, and which had 
 it occurred, is too reniarkal)lr a jih^'nonicnon to have 
 been oveilouke<l. It in, nulecd, generally asserted tha'
 
 158 
 
 OF THE HUMAN MIND. 
 
 Thus, we see that the phaenomena of 
 vision lead us by the hand to a law of na- 
 ture, or a law of our constitution, of which 
 law, our seeing objects erect by inverted 
 images, is a necessary consequence. For 
 it necessarily follows, from the law we have 
 mentioned, that the object whose picture is 
 lowest on the retina must be seen in the 
 highest direction from the eye ; and that 
 the object whose picture is on the right of 
 the retina must be seen on the left ; so 
 that, if the pictures had been erect in the 
 retina, we should have seen the object in- 
 verted. My chief intention in handling 
 this question, was to point out this law ot 
 nature, which, as it is a part of the consti- 
 tution of the human mind, belongs properly 
 to the subject of this inquiry. For this 
 reason, I shall make some farther remarks 
 upon it, after doing justice to the ingenious 
 Dr Porterfield, who, long ago, in the 
 " Medical Essays," or, more lately, in his 
 
 such inversion has never been observed in any 
 patient, surgically restored to sight. I am aware, 
 however, of one case of an opposite purport. It is 
 mentioned, on his own observation, by a very intelli. 
 gent philosopher and physician, Professor Leiden- 
 frost of Duisburg ; and, as his rare work — " Confessio 
 quid putet per Experientiara didicisse de Mente 
 Humana," nOS— is altogether unknown in this 
 country, I shall extract from it the whole passage: — 
 " Hae imagines formantur in organo, non in 
 cerebro. — Mutantur et pervertuntur ab organo laeso, 
 etiamsi illaesiim maiieat cerebrum. Non eas con- 
 natas habemus, sed exercitio continuato eas formare 
 discimus. Elegans exemplum habemus in evangelio 
 Marc. 8. of. loh. 9. Vir adultus a nativitate coecus, 
 et potentia miraculosa sancti servatoris subito curatus 
 primo actu visionis utens distingucre non pnterat, 
 utrumne staturae, quas videbat, homines essent, an 
 arbores. Sine iluhio jam ante ciirationem sciverat ex 
 relatione aliorum,et ex manuura suarumexperientia, 
 tam hominis qiiam stipitis arboreae staturas fsse 
 erectas, at ulteriori exercitio tuerit opus ad utrum- 
 que distinguendum. Aliquid simile aliqiiando in 
 juvene propter cataractam congenitam coeco mihi 
 observare licuit. Hie ex paiipercula familia rustica 
 ortus, statim post partum utraraque pupillam habuit 
 obscuratam; probabiliter membrana piipillaris crassa 
 et opaca erat. I'ro inciirahili habitus nuUam cura- 
 tionem habuit. baiius excrevit, sed plane coecus ; 
 omni lumine orbus, in scholas missus lepidi ingenii 
 signa dedit. Anno aet.itis circiter decimo septimo, 
 nescio ex qua causa gravissima ophthalmia corripitur 
 cum tiimore palpebrariim et acerbo dolore. In hoc 
 statu aliqualis medicatio adhibita est. Observarunt 
 parentes lucem ab eo fugi, a luce riolores crescere. 
 Post aliquot hebdsmades febris et ophthalmia de- 
 crescunt; cum summoejus stuporealiqualemluiiiinis 
 usuram nanciscitur. Omitto scribere plures memora- 
 l.iles hujus visionis conditiones, nam ab eo tempore 
 frequenter, et semper admirans, euin conspexi. Hoc 
 unum, quod ad rem facit, addo ; imagines in oculo 
 orias penitus ei novas fuisse. Ab initio non paiieba- 
 tur sibi persuaderi, reliquo.': homines erectos incederc, 
 putabat hominum capita sui ipsius peilibus esse ob. 
 versa. Similiter arbores et objecta omnia ratione sui 
 inversa esse. Cotorum diversitate vehementer delec- 
 tabatur, quorum nullum conceptum habuerat Nam 
 quamdiu coecus erat, si quid de rubro aut alio colore 
 audiverat, id comparaveratcum sensationibus gustus. 
 Rubrura sibi praesentaverat esse aliquid quasi dulce, 
 nigrum cum amarore comparaverat Successive sibi 
 imagines has formabat, et dijuriicab<ft, ut reliqui ho. 
 m nes. In hoc homine nuUae imagines visivae prae 
 extiteiunt, neque in organo, neque in cerebro, cujus 
 nu la passio aut mutatio facta erat. Aliquot annis 
 post, hie juvenis, non sine meo dolore, phthisicus mo. 
 riebatur," — P. 54. 
 
 " Treatise of the Eye," poinded out,* as a 
 primary law of our nature. That a visible 
 object appears in the direction of a right 
 line perpendicular to the retina at that 
 point where its image is painted. If lines 
 drawn from the centre of the eye to all 
 parts of the retina be perpendicular to it, as 
 they must be very nearly, this coincides 
 with the law we have mentioned, and is the 
 same in other words. In order, therefore, 
 that we may have a more distinct notion 
 of this law of our constitution, we may 
 observe — 
 
 1. That we can give no reason why the 
 retina is, of all parts of the body, the only 
 one on which pictures made by the rays of 
 light cause vision ; and, therefore, we must 
 resolve this solely into a law of our consti- 
 tution. We may form such pictures by 
 means of optical glasses, upon the hand, or 
 upon any other part of the body ; but they 
 are not felt, nor do they produce anything 
 like vision. A picture upon the retina is as 
 little felt as one upon the hand ; but it pro- 
 duces vision, for no other reason that we 
 know, but because it is destined by the 
 wisdom of nature to this purpose. The 
 vibrations of the air strike upon the eye, 
 the palate, and the olfactory membrane, 
 with the same force as upon the membrani 
 tympani of the ear. The impression they 
 make upon the last produces the sensation 
 of sound ; but their impression upon any of 
 the former produces no sen.sation at all. 
 This may be extended to all the senses, 
 whereof each hath its peculiar laws, accord- 
 ing to which the impressions made upon the 
 organ of that sense, produce sensations or 
 perceptions in the mind, that cannot be 
 produced by impressions made upon any 
 other organ. 
 
 2. We may observe, that the laws of per- 
 ception, by the different senses, are very 
 different, not only in respect of the nature 
 of the objects perceived by them, but like- 
 wise in respect of the notices they give us 
 of the distance and situation of the object. 
 In all of them the object is conceived-f- to 
 be external, and to have real existence, in- 
 dependent of our perception : but in one, 
 the distance, figure, and situation of the 
 object, are all presented to the mind ; in 
 another, the figure and situation, but not 
 the distance ; and in others, neither figure, 
 situation, nor distance. In vain do we at- 
 tempt to account for these varieties in the 
 manner of perception by the different 
 
 * Porterfield did not first point this out; on the con. 
 trary, it was a common, if not the common doctrine 
 at tiie time he wrote. See below, the first note of 
 \ xviii. — H. 
 
 f I'he common sense of mankind assures us that 
 the object of sense, is not merely conceited to be ex- 
 ternal, hutperceivedm its externality ; that we know 
 the Non. Ego, not merely mediately, by a representa- 
 tion in the Ego, but immediately, as existing though 
 only as existing in relation to our organs. — H.
 
 OF SEEING 
 
 159 
 
 eeusesj from principles of anatomy or na- 
 tural philosophy. They must at last be 
 resolved mto the will of our Maker, who 
 intended that our powers of perception 
 should have certain limits, and adapted the 
 organs of perception, and the laws of na- 
 ture by which they operate, to his wise pur- 
 poses. 
 
 When we hear an unusual sound, the 
 sensation indeed is in the mind, but we 
 know that there is something external that 
 produced this sound. At the same time, our 
 hearing does not inform us whether the 
 sounding body is near or at a distance, in 
 this direction or that ; and therefore we look 
 round to discover it. 
 
 If any new phrenonieuon appears in the 
 heavens, we see exactly its colour, its ap- 
 parent place, magnitude, and figure ; but 
 we see not its distance. It may be in the 
 atmosphere, it may be among the planets, 
 or it may be in the sphere of the fixed stars, 
 for anything the eye can determine. 
 
 The testimony of the sense of touch 
 reaches only to objects that are contiguous 
 to the organ, but, with regard to them, is 
 more precise and determinate. AVheii we 
 feel a body with our hand, we know the 
 figure, distance, and position of it, as well 
 as whether it is rough or smooth, hard or 
 soft, hot or cold. 
 
 The sensations of touch, of seeinjr, and 
 hearmg, are all in the mind, and can have 
 no existence but when they are perceived. 
 How do they all constantly and invariably 
 suggest the conception and belief of external 
 objects, which exist whether they are per- 
 ceived or not ? No philosopher can give 
 any other answer to this, but that such is 
 the constitution of our nature. How do we 
 know that the oljjcct of touch is at the 
 finger's end, and nowhere else ? — that the 
 object of sight is in such a direction from 
 the eye, and in no other, but may be at any 
 distance ?* — and that the object of hearing 
 may be at any distance,* and in any direc- 
 tion ? Not by custom surely — not by rea- 
 soning, orcomjiaring ideas — but by the con- 
 stitution of our nature. How do we ])er- 
 ceive visible objects in the direction of riglit 
 lines perpendicular to that part of the retina 
 on which the rays strike, while we do not 
 jterceive the objects of hearing in lines per- 
 pendicular to the meinbraiia iipnpani u])on 
 which the vibrations of the air strike ? Jic- 
 cause such are the laws of our nature. How 
 'io we know the parts of our bodies aff(;cted 
 by particular pains ? Not by experience 
 <)r by reasoning, but by the constitution of 
 nature. The sensation of pain is, no doubt, 
 in the mind, and cannot be said to have any 
 relation, from its own nature, to any part 
 
 • It has been previously nnticfd, tliat in no sense 
 'I'TR the mind percnvf .-my di taut or mediate oh. 
 ject,_ll. 
 
 of the body ; but this sensation, by our con- 
 stitution, gives a perception of some parti- 
 cular part of the body, whose disorder causes 
 the uneasy sensation. If it were not so, a 
 man who never before felt either the gout 
 or the toothache, when he is first seized with 
 the gout in his toe, might mistake it for 
 the toothache. 
 
 Every sense, therefore, hath its peculiar 
 laws and limits, by the constitution of our 
 nature ; and one of the laws of sight is, that 
 we always see an object in the direction of 
 a right line, passing from its image on the 
 retina through the centre of the eye. 
 
 3. Perhaps some readers will imagine 
 that it is easier, and will answer the pur- 
 pose as well, to conceive a law of nature, 
 by which we shall always see objects in 
 the place in which they are, and in their 
 true position, without liaving recourse to 
 images on the retina, or to the optical centre 
 of the eye. 
 
 To this I answer, that nothing can be a 
 law of nature which is contrary to fact. 
 The laws of nature are the most general 
 facts we can discover in the operations of 
 nature. Like other facts, they are not to 
 be hit upon by a happy conjecture, but 
 justly deduced from observation ; like other 
 general facts, they are not to be drawn from 
 a few particulars, but from a copious, pa- 
 tient, and cautious induction. That we see 
 things always in their true place and posi- 
 tion, is not fact ; and therefore it can be no 
 law of nature. In a plain mirror, I see 
 myself, and other things, in places very 
 different from those they really occupy." 
 And so it happens in every instance where- 
 in the rays coming from the object are 
 either reflected or refracted before falling 
 upon the eye. Those who know anything 
 of optics, know that, in all such cases, the 
 object is seen in the direction of a line 
 passing from the centre of the eye, to the 
 point where the rays were last reflected 
 or refracted ; and that upon this all the 
 powers of the telescope and microscope 
 depend. 
 
 Shall we say, then, that it is a law of 
 nature, that the object is seen in the direc- 
 tion which the rays have when tlicy fall 
 on the eye, or rather in the direction con- 
 trary to that of the rays when they fall 
 upon the eye ? No. This is not true ; 
 and therefore it is no law of nature. For 
 the rays, from any one jjoint of the object, 
 come to all parts of the ]iupil ; and there- 
 fore must have difl'creiit direct i(ins : but we 
 sec the object only in oiic of tliCKO direc- 
 tions — to wit, in the direction of the rays 
 that come to the centre of the eye. And 
 this holds true, even when the rays that 
 should i)ass through the centre are stopped. 
 
 • 'J'lils i« a very inarciiralc ttatcmrnt. In a 
 inirrnr I do not see myself, Ac.— II.
 
 J 60 
 
 OF THE HUMAN MIND. 
 
 and the object is seen by rays that pass at a 
 distance from the centre." 
 
 Perliaps it may still be imagined, that, 
 although we are not made so as to see ob- 
 jects always in their true place, nor so as to 
 see them precisely in the direction of the 
 rays when they fall upon the curnea ; yet 
 we may be so made as to see the object 
 in the direction which the rays have when 
 they fall upon the retina, after they have un- 
 dergone all their refractions in the eye — 
 that is, in the direction in which the rays 
 pass from the crystalline to the reiina. But 
 neither is this true ; and consequently it is 
 no law of our constitution. In order to 
 .see that it is not true, we must conceive all 
 the rays that pass from the crystalline to 
 one point of the retina, as forming a small 
 cone, whose base is upon the back of the 
 crystalline, and whose vertex is a point of 
 the retina. It is evident that tlie rays which 
 form the picture in this point, have various 
 directions, even after they pass the crystal- 
 line : yet the object is seen only in one of 
 these directions — to wit, in the direction of 
 the rays that come from the centre of the 
 eye. Nor is this owing to any particular 
 virtue in the central rays, or in the centre 
 itself; for the central rays may be stopped. 
 When they are stopped, the image will be 
 formed upon the same point of the retina as 
 before, by rays that are not central, nor have 
 the same direction which the central rays 
 liad : and in this case the object is seen in the 
 same direction as before, although there 
 are now no rays coming in that direction. * 
 
 From this induction we conclude, That 
 our seeing an object in that particular di- 
 rection in which we do see it, is not owing to 
 any law of nature by which we are made to 
 see it in the direction of the rays, either be- 
 fore their refractions in the eye, or after, 
 but to a law of our nature, by which we 
 see the object in the direction of the right 
 line that passeth from the picture of the 
 object upon the retina to the centre of the 
 eye.f 
 
 * But still we always see in the direction of a line 
 made up of the directions of all the rays of the pencil, 
 and this line necessarily coincides with the direction 
 of (he central ray, even where that ray itself is inter, 
 cepted; for the central line would still be theme, 
 dium of allthe lines of the various divergent or con. 
 vergent rays in the pencil — H. 
 
 + It IS incorrect to say that " we see the object," 
 (meaning the thing from which the rays come 
 by emanation or reflection, but which is unknown 
 and incognizable by sight,) and so forth. It would 
 be more correct to describe vision— a perception, by 
 whirh we take immeiliate cognizaiire of hght in re- 
 lation to our or^an — that is, as difl'used and figured 
 upcn the retina, und r various modifications of de. 
 greeand kind, (brightness and colour,) — and likewise 
 as falling on it in a particular direction. The image 
 on the retina is "ot itseU an object of visual per. ep. 
 tion. It is only to be regar.led as the complement of 
 those poiiits, or of that sensitive surface, on which 
 the rays impinge, and with which they enter into re- 
 lation. The total object of visual perception is thus 
 neither the rays in themselves, nor the organ in it 
 self, but the rays and the living organ in reciprocity : \ 
 
 The facts upon which I ground this in- 
 duction, are taken from some curious ex- 
 periments of Scheiner, in his " Fundamen- 
 tum Opticum," quoted by Dr Porterfield, 
 and confirmed by his experience. I have 
 also repeated these experiments, and found 
 them to answer. As they are easily made, 
 and tend to illustrate and confirm the law 
 of nature I have mentioned, I shall recite 
 them as briefly and distinctly as I can. 
 
 Experiment 1. Let a very small object, 
 such as the head of a pin, well illuminated, 
 be fixed at such a distance from the eye as 
 to be beyond the nearest limit and within 
 the farthest limit of distinct vision. For a 
 young eye, not near-sighted, the object may 
 be placed at the distance of eighteen inches. 
 Let the eye be kept steadily in one place, and 
 take a distinct view of the object. We 
 know, from the principles of optics, that 
 the rays from any one point of this object, 
 whether they pass through the centre of the 
 eye, or at any distance from the centre 
 which the breadth of the pupil will permit, 
 do all unite again in one point of the retina. 
 We know, also, that these rays have differ- 
 ent directions, both before they fall upon 
 the eye, and after they pass through the 
 cry.stalliue. 
 
 Now, we can see the object by any one 
 small parcel of these rays, excluding the 
 rest, by looking through a small pin-hole in 
 a card. Moving this pin-hole over the 
 various parts of the pupil, we can see the 
 object, first by the rays that pass above the 
 centre of the eye, then by the central rays, 
 then by the rays that pass below the centre, 
 and in like manner by the rays that pass on 
 the right and left of the centre. Thus, we 
 view this object, successively, by rays that 
 are central, and by rays that are not central ; 
 by rays that have different directions, and 
 are variously inclined to each other, both 
 when they fall upon the cornea, and when 
 they fall upon the retina ; but always by 
 rays which fall upon the same point of the 
 retina. And what is the event ? It is this — 
 that the object is seen in the same individual 
 direction, whether seen by all these rays to- 
 gether, or by any one parcel of them. 
 
 Experiment 2. Let the object above 
 mentioned be now placed within the nearest 
 limit of distinct vision — that is, for an eye 
 that is not near-sighted, at the distance of 
 
 this organ is not, however, to be viewed as merely 
 the retina, but as the whole tract of nervous fibre 
 pertaining to the sense. In an act of vision, so 
 also in the other sensitive acts, 1 am thus cun- 
 scious, (the word should not be restricted to self, 
 consciousness,) or immediately cognizant, not only 
 of the aflections of self, but of ihe pha;iiomena of 
 something different from ^eA, both, however, always 
 in relation to each other. According, as in differ- 
 ent senses, the subjective or the objfctiv:' element 
 pieponderates, we haves nsation ox pcrciption, the 
 secunda'!/ or the/)'»>«a'y qualit es of matter ; dis- 
 tinctions which are thus identified and carried up 
 into a general law. But of this again.— il.
 
 OF SEEING. 
 
 IGl 
 
 four or five Inches. We know that, in this 
 case, the rays eouiing from one point of the 
 object do not meet in one point of the retina, 
 but spread over a small circular spot of it ; 
 the central rays occupying the centre of this 
 circle, the rays that pass above the centre 
 occupying the upper part of the circular spot, 
 and so of the rest- And we know that the 
 object is, in this case, seen confused; every 
 pohit of it being seen, not in one, but in 
 various directions. To remedy this confu- 
 sion, we look at the object through the pin- 
 hole, and, while we move the pin-hole over 
 the various parts of the pupil, the object 
 does not keep its place, but seems to move in 
 a contrary direction. 
 
 It is here to be observed, that, when the 
 ])in-hole is carried upwards over the pupil, 
 the picture of the object is carried upwards 
 upon the retina, and the object, at the same 
 time, seems to move downwards, so as to be 
 always in the right line, passing from the 
 picture through the centre of the eye. It is 
 likewise to be observed, that the rays which 
 form the upper and the lower pictures upon 
 the retina do not cross each other, as in or- 
 dinary vision; yet, still, the higher picture 
 shews the object lower, and the lower pic- 
 ture shews the object higher, in the same 
 manner as when the rays cross each other. 
 Whence we may observe, by the way, that 
 this phtenomenon of our seeing objects in a 
 position contrary to that of their pictures 
 upon the retina, does not depend upon the 
 crossing of the rays, as Kepler and Des 
 Cartes conceived. 
 
 Experiment 3. Other things remaining 
 as in the last experiment, make three pin- 
 holes in a straight lii.ie, so near that the rays 
 comingfrom the object through all the holes 
 may enter the pupil at the same time. In 
 this case, we have a very curious phenome- 
 non ; for the object is seen triple witli one 
 eye. And if you make more holes within 
 the breadth of the pupil, you will see as many 
 objects as there are holes. However, we 
 shall suppose them only three — one on the 
 right, one in the middle, and one on the left ; 
 in which case you see three olijects standing 
 in a line from right to left. 
 
 It is here to be observed, that there are 
 three pictures on the retina ; that on the 
 left being formed by the rays which i)ass 
 on the left of the eye's centre, the middle 
 picture being formed by the central rays, 
 and the right-hand picture by the rays 
 which pass on the right of the eye's centre. 
 It is farther to be observed, that the object 
 whicii appears on the right, is not that 
 whicii is seen through the hole on tlie right, 
 but that which is seen through the hole on 
 the left ; and, in like manner, the left- 
 hand object is seen through the hole on 
 tlie riglit, as is easily proved by covering 
 the holes Hucccssivcly : so that, wiiatever 
 
 is the direction of the rays which form the 
 right-hand and left-hand pictures, still the 
 right-hand picture shews a left-hand object, 
 and the left-hand picture shews a right- 
 hand object. 
 
 Experiment 4. It is easy to see how the 
 two last experiments may be varied, by 
 placing the object beyond the farthest limit 
 of distinct vision. In order to make this 
 experiment, I looked at a candle at the dis- 
 tance of ten feet, and put the eye of my 
 spectacles behind the card, that the rays 
 from the same point of the object might 
 meet and cross each other, before they 
 reached the retina. In this case, as in the 
 former, the candle was seen triple through 
 the three pin-holes ; but the candle on the 
 right was seen through the hole on the 
 right ; and, on the contrary, the left-hand 
 candle was seen through the hole on the 
 left. In this experiment it is evident, 
 from the principles of optics, that the rays 
 forming the several pictures on the retina 
 cross each other a little before they reach 
 the retina ; and, therefore, the left-hand 
 picture is formed by the rays which pass 
 through the hole on the right : so that the 
 [losition of the jiictures is contrary to that 
 of the holes by which they are formed ; and, 
 therefore, is also contrary to that of their 
 objects — as we have found it to be in the 
 former experiments. 
 
 These experiments exhibit several un- 
 common phoenoraena, that regard the appa- 
 rent place, and the direction of visible 
 objects from the eye ; phenomena that 
 seem to be most contrary to the common 
 rules of vision. When we look at the same 
 time through three holes that are in a right 
 line, and at certain distances from each 
 othei', we expect that the objects seen 
 through them should really be, and should 
 ai)pear to be, at a distance from each other. 
 Yet, liy the first experiment, wo may, 
 through three such holes, see the same 
 olijeet, and the same ]ioint of that object ; 
 and through all the three it apjjoars in the 
 same individual jilace and direction. 
 
 When the rays of light come Iroin the 
 object in right lines to the eye, without 
 any reflection, inflection, or refraction, wo 
 expect that the object should appear in its 
 real and proper direction from the eye ; 
 and so it commonly does. But in the 
 second, third, and fourth exi)eriments, wo 
 see the object in a direction which is not 
 its true and real direction from the eye, 
 although tlio rays come from the object to 
 the eye, without any inflection, reflection, 
 or refraction. 
 
 When both the object and the eye are 
 fixed without the least motion, and the 
 medium unchanged, wo expect that the 
 object should ap])ear to rest, and keep the 
 same place. Y<t, in the sccon<l and fourth
 
 162 
 
 OF THE HUMAN MIND. 
 
 experiments, when both the eye and the ob- 
 ject are at rest, and the medium unchanged, 
 we make the ol)ject appear to move upwards 
 or downwards, or in any direction we please. 
 
 When we look, at tlie same time and 
 Irith the same eye, through holes tliat stand 
 in a line from right to left, we expect 
 that the object seen through the left- 
 hand hole should appear on the left, and the 
 object seen through the right-hand hole 
 should appear on the right. Yet, in the third 
 experiment, we find the direct contrary. 
 
 Although mjiny instances occur in see- 
 ing the same object double with two eyes, 
 we always expect that it should appear 
 single when seen only by one eye. Yet, in 
 the second and fourth experiments, we have 
 instances wherein the same object may 
 appear double, triple, or quadruple to one 
 eye, without the help of a polyhedron or 
 multiplying glass. 
 
 All these extraordinary phtenomena, re- 
 garding the direction of visible objects from 
 the eye, as well as those that are common 
 and ordinary, lead us to that law of nature 
 which I have mentioned, and are the neces- 
 sary consequences of it. And, as there is 
 no probability that we shall ever be able to 
 give a reason why pictures upon the relina 
 make us see external objects, any more 
 than pictures upon the hand or upon the 
 cheek ; or, that we shall ever be able to 
 give a reason, why we see tlie object in the 
 direction of a Hue passing from its picture 
 through the centre of the eye, rather than 
 in any other direction — I am, therefore, apt 
 to look upon this law as a primary law of 
 our constitution. 
 
 To prevent being misunderstood, I beg 
 the reader to observe, that I do not mean 
 to affirm that the picture upon the retina 
 will make us see an object in the direction 
 mentioned, or in any direction, unless the 
 optic nerve, and the other more immediate 
 instruments of vision, be sound, and per- 
 form their function. We know not well 
 what is the office of the optic nerve, nor in 
 what manner it performs that office ; but 
 that it hath some part in the faculty of see- 
 ing, seems to be certain ; because, in an 
 amaurosis, which is believed to be a disorder 
 of the optic nerve, the pictures on the relina 
 are clear and distinct, and yet there is no 
 vision. 
 
 We know still less of the use and func- 
 tion of the choroid membrane ; but it seems 
 likewise to be necessary to vision : for it is 
 well known, that pictures upon that part of 
 the relina where it is not covered by the 
 choroid — I mean at the entrance of the 
 optic nerve— produce no vision, any more 
 than a picture upon the hand. " We ac. 
 
 * Reid hereatJopfs the theory of Mariotfe, who first 
 discovered the curious fact of this local insensibility, 
 
 knowledge, therefore, that the retina is not 
 the last and most immediate instrument of 
 the mind in vision. There are other mate- 
 rial organs, whose operation is necessary to 
 seeing, even after the pictures upon the 
 retina are formed. If ever we come to 
 know the structure and use of the choroid 
 membrane, the optic nerve, and the brain, 
 and what impressions are made upon them 
 by means of the pictures on the retina, 
 some more links of the chain may be brought 
 within our view, and a more general law 
 of vision discovered ; but, while we know 
 so little of the nature and office of these 
 more immediate instruments of vision, it 
 seems to be impossible to trace its laws be- 
 yond the pictures upon the retina. 
 
 Neither do I pretend to say, that there 
 may not be diseases of the eye, or accidents, 
 which may occasion our seeing objects in a 
 direction somewhat different from that men- 
 tioned above. I shall beg leave to mention 
 one instance of this kind that concerns my- 
 self. 
 
 In May 1761) being occupied in making 
 an exact meridian, in order to observe the 
 transit of Venus, I rashly directed to the 
 sun, by my right eye, the cross hairs of a 
 small telescope, I had often done the like 
 in my younger days with impunity ; but I 
 suffered by it at last, which I mention as a 
 warning to others. 
 
 I soon observed a remarkable dimness in 
 that eye ; and for many weeks, when I was 
 in the dark, or shut my eyes, there ap- 
 peared before the right eye a lucid spot, 
 which trembled much like the image of the 
 sun seen by reflection from water. This 
 appearance grew fainter, and less frequent, 
 by degrees ; so that now there are seldom 
 any remains of it. But some other very 
 sensible effects of this hurt still remain. 
 For, First, The sight of the right eye con- 
 tinues to be more dim than that of the left. 
 Secondly, The nearest limit of distinct 
 vision is more remote in the right eye than 
 in the other ; although, before the time 
 mentioned, they were equal in botli these 
 respects, as I had found by many trials. 
 But, thirdly, what I chiefly intended to 
 mention is, That a straight line, in some 
 circumstances, appears to the ri^ht eye to 
 have a curvature in it. Thus, when I look 
 upon a music book, and, shutting my left 
 eye, direct the right to a point of the mid- 
 
 and who ingeniously employed it in support of his 
 opinion, that the choroid, not the retina, is the 
 proximate organ m vision. Hut not only is theab. 
 sence of the choroid not to be viewed as the cause of 
 this phseiiomenon ; it is not even to be attributed to 
 the entrance of the optic nerve. For it is proved 
 that the impassive portion of the retina does not 
 occupy above a third part of the disc, corresponding 
 to the circumference of that nerve ; and the conjec- 
 ture of Kuddlphi seems probable, that the insensi. 
 bility i-» limited to the spot Avhere the arttria centralit 
 enters. — H.
 
 OF SEEING. 
 
 163 
 
 die line of the five which compose the staff 
 cf music, the middle line appears dim, in- 
 deed, at the point to which the eye is di- 
 rected, but straight ; at the same time, the 
 two lines above it, and the two below it, 
 appear to be bent outwards, and to be more 
 distant from each other and from the middle 
 hue, than at other parts of the staff, to 
 which the eye is not directed. Fourthly, 
 Although I iiave repeated this experiment 
 times innumerable, within these sixteen 
 months, I do not find that custom and ex- 
 perience takes away this appearance of cur- 
 vature m straight lines. Lastly, This ap- 
 pearance of curvature is perceptible when 
 I look with the right eye only, but not when 
 I look with both eyes; yet I see better 
 witli both eyes together, than even with 
 the left eye alone. 
 
 I have related this fact minutely as it is, 
 without regard to any hypothesis ; because 
 I think such uncommon facts deserve to be 
 recorded. I shall leave it to others to con- 
 jecture the cause of this appearance. To 
 me it seems most probable, that a small 
 part of the retina towards the centre is 
 shrunk, and that thereby the contiguous 
 parts are drawn nearer to the centre, and 
 to one another, than they were before ; and 
 that objects, whose images fall on these 
 parts, appear at that distance from each 
 other which corresponds, not to the interval 
 of the parts in their present preternatural 
 contraction, but to their interval in their 
 natural and sound state. 
 
 Section XIII. 
 
 OF SEEING OBJECTS SINGLE WITH TWO EYES. 
 
 Another phsenomenon of vision which 
 deserves attention, is our seeing objects 
 single with two eyes. * There are two pic- 
 
 * nie opinions relative to single vision with two 
 cyt-i, may, I \hm\i,he jeduQedia tivu supreme classes. 
 i he one attempts to shew that Here is no tiifficulty 
 to be solved ; the othcatttniptsto solve thedifiiculty 
 which is admitted.— Under \hc former class, there 
 are, as 1 recollect, Mre^ hypotheses, ihe Jirst >u\>- 
 poses that we see only with one eye— that man is in 
 reality a Cyclops; the tecond supposcr> that the two 
 impiesjion-. are not, in fact, made at the fame instatit 
 In iioth eyes, and, consequently, that two simulta- 
 neou< impressions are not conveyed to the tram and 
 mind; the H^nct sup[>osos that, although a separate 
 impresfion he made on each retina, yet that tlie~e 
 ■evcral impression- are, as it were, fused into one 
 before they reach the common sensory, in coiise. 
 quence ol a union of the optic nerves. — I'hc hypo, 
 ttiest* of the latter class which, I think, may also be 
 reduced to Mr<re, all admit that there are slinuUaiicoiis 
 impressions on the two reti7>(C, and that these ini. 
 prtsuioni" are separa'ely conveyiil to the termination 
 of the organic a| paratus ; but still hold thai, in the 
 mind, there u dttermincd only a single perception. 
 One opinion allows the perception to have been origi- 
 nally twofold, and tavcs the phajiiomenon, by 6iip|ios. 
 iiig that it became single througl. the influence of cus. 
 tonwind association. Another ex]ilalns it more siib- 
 'OctiTcly, by an ultimate and inexplicable law of uur 
 
 tures of the object, one on each retina , 
 and each picture by itself makes us see an 
 object in a certain direction from the eye ; 
 yet both together commonly make us see 
 only one object. All the accounts or solu- 
 tions of this phtenomenon given by anato- 
 mists and philosophers seem to be unsatisfac- 
 tory. I shall pass over the opinions of Galen, 
 of Gassendus, of Baptista Porta, and of Ro- 
 hault. The reader may see these examined 
 and refuted by Dr Porterfield. I shall ex- 
 amine Dr Porterfield's own opinion, Bishop 
 Berkeley's, and some others. But it will be 
 necessary first to ascertain the facts : for, if 
 we mistake the phaenomena of single and 
 double vision, it is ten to one but this mis- 
 take will lead us wrong in assigning the 
 causes. This likewise we ought carefully to 
 attend to, w^hich is acknowledged in theory 
 by all who have any true judgment or just 
 taste in inquiries of this nature, but is very 
 often overlooked in practice — namely, that, 
 in the solution of natural phenomena, all 
 the length that the human faculties can 
 carry us, is only this, that, from particular 
 phsenomena, we may, by induction, trace 
 out general phsenomena, of which all the 
 particular ones are necessary consequences. 
 And when we have arrived at the mo.st 
 general phcenomena we can reach, there 
 we must stop. If it is asked. Why such a 
 body gravitates towards the earth ? all the 
 answer that can be given is. Because all 
 bodies gravitate towards the earth. This 
 is resolving a particular pluenomenon into 
 a general one. If it should again be asked, 
 Why do all bodies gravitate towards the 
 earth ? we can give no other solution of this 
 phfenomenon, but that all bodies whatso- 
 ever gravitate towards each other. This 
 is resolving a general phenomenon into a 
 more general one. If it should be asked. 
 Why all bodies gravitate to one anotlier ? we 
 cannot tell ; but, if wc could tell, it could 
 only be by resolving this universal gravita- 
 tion of bodies into some other pluvnomenon 
 still more general, and of which the gravi- 
 tation of all bodies is a i)articular instance. 
 The most general plucnoinena we can reach, 
 are what we call law.s cfnaivre ; so that the 
 laws of nature are nothing else but the most 
 general facts relating to the operations of 
 nature, which include a great many parti- 
 cular facts under them. And if, in any case, 
 we should give the name (jf a law of nature 
 to a general phaiiionicnon, which human 
 i: dustry bhall afterwards trace to one more 
 general, there is no groat liarm done. The 
 most general as.sumcs the name of a law of 
 nature when it is discovered, and the less 
 general is contained and comprehended in 
 it. Ilavuig premised these things, we pro- 
 ceed to consider the jihiBiiomena of single 
 
 constitution ; and the lust, morcobjcctively.oneom* 
 intelligible principle of optics.— II. 
 
 .M -J
 
 OF TllK HU.VLVN MIND 
 
 nul double vision, in order to discover some 
 general princii)lo towhicli they all lead, and 
 of which they are the necessary conse- 
 quences. ]f we can discover any such 
 general iJrineiplc, it must either be a law of 
 nature, or the necessary consequence of 
 some law of nature ; and its authority will 
 be equal whether it is the first or the last. 
 
 1. We find that, when the eyes are sound 
 and perfect, and the axes of both directed 
 to one point, an object placed in that point is 
 seen single — and here we observe, that in 
 this case the two pictures which shew the 
 object single, are in the centres of the 
 retina. When two pictures of a small 
 object are formed upon points of the retina, 
 if they shew the object single, we shall, for 
 the sake of perspicuity, call such two points 
 of the retina, corresponding points ; and 
 where the object is seen double, we shall 
 call the points of the retina on which the 
 pictures are formed, points that do not cor- 
 respond.* Now, in this first phaBuomenon, 
 it is evident, that the two centres of the 
 retina are corresponding points. 
 
 2. Supposing the same things as in the 
 last plioenomcnon, other objects at the same 
 distance from the eyes as that to which 
 their axes are directed, do also appear 
 single. Thus, if I direct my eyes to a 
 candle placed at the distance of ten feet, 
 and, while I look at tliis candle, another 
 stands at the same distance from my eyes, 
 within the field of vision, I can, while I 
 look at the first candle, attend to the ap- 
 pearance which the second makes to the 
 eye ; and I find that in this case it always 
 appears single. It is here to be observed, 
 that the pictures of the second candle do 
 not fall upon the centres of the relincB, but 
 they both fall upon the same side of the 
 centres — that is, both to the right, or both 
 to the left ; and both are at the same dis- 
 tance from the centres. This might easily 
 be demonstrated from the principles of 
 optics. Hence it appears, that in this 
 second phenomenon of single vision, the 
 corresponding points are points of the two 
 retince, which are similarly situate with 
 respect to the two centres, being both upon 
 the same side of the centre, and at the same 
 distance from it. It appears likewise, from 
 this phtenomenon, that every point in one 
 retina corresponds with that which is simi- 
 larly situate in the other. 
 
 • It is to be not ircd that Reid uses the terms, cor- 
 respondini; points in a sense opposite to that of 
 Smith, and .-ome optical writers; they UivM analomi- 
 cally, he phtjsiolr>i;icnlly. Two points are anatomi. 
 cally corrrspondent, when on opposite sides oi the 
 body they scverallv hold the same relation to the 
 centre. J. Mueller, and oihcr recent physiologists, 
 employ these terms in the fame signification hs Reid. 
 An argument « )iriori has been employed ag.iinst 
 the doctrine here maii taiiied, on the groun.l that 
 the congruent points in the opposite eyes are imt 
 anatomically corresponding points. — 11. 
 
 .'}. Supposing still the same things, ob- 
 jects which are much nearer to the eyes, or 
 much more distant from them, than that 
 to which the two eyes are directed, ai)])ear 
 double. Thus, if the candle is placed at 
 the distance of ten feet, and I hold my finger 
 at arms-length between my eyes and the can- 
 dle — w hen I look at the candle, I see my fin- 
 ger double ; and when I look at my finger, 
 1 see the candle double ; and the same thing 
 happens with regard to all other objects at 
 like distances which fall within the sphere 
 of vision. In this phrenomenon, it is evi- 
 dent to those who understand the prin- 
 ciples of optics, that the pictures of the ob- 
 jects which are seen double, do not fall upon 
 points of the retina which are similarly sit- 
 uate, but that the pictures of the objects 
 seen single do fall upon points similarly 
 situate. Whence we infer, that, as the points 
 of the two retina, which are similarly situate 
 with regard to the centres, do correspond, 
 so those which are dissimilarly situate do 
 not correspond. 
 
 4. It is to be observed, that, although, in 
 such cases as are mentioned in the last 
 phrenomenon, we have been accustomed 
 from infancy to see objects double which 
 we know to be single ; yet custom, and ex- 
 perience of the unity of the object, never 
 take away this appearance of duplicity. 
 
 5. It may, however, be remarked that 
 the custom of attending to visible appear- 
 ances has a considerable effect, and makes 
 the phfonomenon of double vision to be more 
 or less observed and remembered. Thus 
 you may find a man that can say, with a 
 good conscience, that he never saw things 
 double all his life ; yet this very man, put 
 in the situation above mentioned, with his 
 finger between him and the candle, and de- 
 sired to attend to the appearance of the 
 object which he does not look at, will, upon 
 the first trial, see the candle double, when 
 he looks at his finger ; and his finger double, 
 w hen he looks at the candle. Does he now 
 see otherwise than he saw before ? No, 
 surely ; but he now attends to what he 
 never attended to before. The same double 
 appearance of an object hath been a thou- 
 sand times presented to his eye before now, 
 but he did not attend to it ; and so it is as 
 little an object of his reflection and memory, 
 as if it had never happened. 
 
 When we look at an object, the circum- 
 jacent objects may be seen at the same 
 time, although more obscurely and indis- 
 tinctly : for the eye hath a considerable 
 field of vision, which it takes in at once. 
 But we attend only to the object we look at. 
 The other objects which fall within the field 
 of vision, ;iro not attended to ; and therefore 
 are as if they were not seen. If any of 
 tlicm draws our attention, it naturally draws 
 the eyes at the same time : for, in the com-
 
 OF SEEING. 
 
 165 
 
 mou course of life, the eyes always follow 
 the attention : or if at any time, in a revery, 
 tliey are separated from it, we hardly at 
 that time see what is directly before us. 
 Hence we may see the reason why the man 
 we are speaking of thinks that he never 
 before saw an object double. When he 
 looks at any object, he sees it single, and 
 takes no notice of other visible objects at 
 that time, whether they appear single or 
 double. If any of them draws his attention, 
 it draws his eyes at the same time ; and, as 
 soon as the eyes are turned towards it, it 
 appears single. But, in order to see things 
 double — at least, in order to have any reflec- 
 tion or remembrance that he did so — it is 
 necessary that he should look at one object, 
 and at the same time attend to the faint 
 appearance of other objects which are within 
 the field of vision. This is a practice which 
 perhaps he never used, nor attempted ; and 
 therefore he does not recollect that ever he 
 saw an object double. But when he is put 
 upon giving this attention, he immediately 
 sees objects double, in the same manner, and 
 with the very same circumstances, as they 
 who have been accustomed, for the greatest 
 part of their lives, to give this attention. 
 
 There are many pha?nomena of a similar 
 nature, which shew that the mind may not 
 attend to, and thereby, in some sort, not 
 perceive objects that strike the senses. I 
 had occasion to mention several instances 
 of this in the second chapter; and I have 
 been assured, I.y persons of the best skill in 
 music, that, in hearing a tune upon the 
 harpsichord, when they give attention to 
 the treble, they do not hear the bass ; and 
 when they attend to the bass, they do not 
 perceive the air of the treble. Some per- 
 sons are so near-sighted, that, in reading, 
 they hold the book to one eye, while the 
 other is directed to other objects. Such 
 persons acquire the habit of attending, in 
 this case, to the objects of one eye, while 
 they give no attention to those of the other. 
 
 6. It is observable, that, in all cases 
 wherein we see an object double, the two 
 appearances have a certain position with 
 regard to one another, and a certain apjiar- 
 ent or angular distance. This apparent 
 distance is greater or less in difi'erent cir- 
 cumstances; but, in the same circumstances, 
 it is always the snme, not only to the same, 
 but to different j)ersons. 
 
 Thus, in the experiment above mentioned, 
 if twenty different ])ersoiis, who see perfectly 
 with both eyes, shall jilaec their finger and 
 the candle at the distances above exjiressed, 
 and hold their heads upright, 'ooking at the 
 finger, they will see (wo candles, one on the 
 right, another on the left. That which is 
 seen on tl:i' ri;:ht, i.'i seen by the right eye, 
 an<l that which is Hccn on the left, by the 
 left eye ; .hkI lliry will see thi in at the name 
 
 apparent distance from each other. If, 
 again, they look at the candle, they will 
 see two fingers, one on the right, and the 
 other on the left ; and all will see them at 
 the same apparent distance ; the finger 
 towards the left being seen by the right eye, 
 and the other by the left. If the head is 
 laid horizontally to one side, other circum- 
 stances remaining the same, one appearance 
 of the object seen double, will be directly 
 above the other. In a word, vary the cir- 
 cumstances as you please, and tlie appear- 
 ances are varied to all the spectators in one 
 and the same manner. 
 
 7. Having made many experiments in 
 order to ascertain the apparent distance of 
 the two appearances of an object seen double, 
 I have found that in all cases this apparent 
 distance is proportioned to the distance be- 
 tween the point of the reihia, where the 
 picture is made in one eye, and the point 
 which is situated similarly to that on which 
 the picture is made on the other eye ; so 
 that, as the apparent distance of two objects 
 seen with one eye, is proportioned to the 
 arch of the retina, which lies between their 
 pictures, in like manner, when an object is 
 seen double with the two eyes, the apparent 
 distance of the two appearances is propor- 
 tioned to the arch of either reihia, which 
 lies between the picture in that retina, and 
 the point corresponding to tliat of the pic- 
 ture in the other retina. 
 
 8. As, in certain circumstances, we in- 
 variably see one object appear double, so, 
 in others, we as invariably see two objects 
 unite into one, and, in appearance, lose 
 their duplicity. This is evident in the aj)- 
 pearance of the binocular telescope. And 
 the same thing hapjiens when any two simi- 
 lar tubes are ajjplied to the two eyes in a 
 parallel direction ; for, in this ease, we see 
 only one tube. And if two shillings are 
 placed at the extremities of the two tubes, 
 one exactly in the axis of one eye, and the 
 other in the axis of the other eye, we shall 
 see but one shilling. If two pieces of coin, 
 or other bodii s, of different colour, and of 
 different figure be proj»erly placed in the 
 two axes of the eyes, and at the extremi- 
 ties of the tubes, we shall see both the 
 bodies in one and the same place, each as 
 it were spread over the other, without hid- 
 ing it ; and the colour will be that which is 
 compounded of the two colours.* 
 
 • 'J Ills las' statenicnl isincnrrcc-t ; it misrcprcsontsi 
 il it (Iocs not rcvrrse, tlie observation of Dii I our- 
 Hut, thoiifih Kciil's Hsscrlion lie inaccuiatc, tlicru is 
 (;rtat (iiHi'R'iico (prol'a ly Ironi tlu- diflorent <o. sti- 
 tution of tlifir organs; in tlii' plio'iionieno , as re. 
 ported liy various ol)scrvtr«. Noni', seoiiiingly, 
 (tlif rfTcrse ol wliat Him<I i-ajs,) in lookini;, <•. /;., 
 will) one eye tliroijjjli a blue, atid with li o otiipr 
 lliroiij:!) a yellow fi,\Ms, experience n rcmiple- 
 nienlary scnsalini of green. Hut some ^ee lioili 
 eolours at once; some only one colour— a colour, 
 however, wli eh coirespomls ni'ithi 1 to yelh w nor t'l 
 liliie, and, at the fnine time Is iiol ({"f"- '" " V
 
 166 
 
 OF THE HUMAN MIND. 
 
 9. From these phcenomena, and from all 
 the trials I have been able to make, it ap- 
 pears evidently, that, in perfect human eyes, 
 the centres of the two retince correspond and 
 harmonize wth one another, and that every 
 other point in one retina doth correspond 
 and harmonize with the point whicii is 
 similarly situate in the other ; in such man- 
 ner, that pictures falling on the corre- 
 eponding points of the two retince, shew 
 only one object, even when there are really 
 two ; and pictures falling upon points of 
 the retincB which do not correspond, shew 
 us two visible appearances, although there 
 be but one object : so that pictures, upon 
 corresponding points of the two retince, pre- 
 sent the same appearance to the mind as 
 if they had both fallen upon the same point 
 of one retina ; and pictures upon points of 
 the two retinae, which do not correspond, 
 present to the mind the same apparent 
 distance and position of two objects, as if 
 one of those pictures was carried to the 
 point corresponding to it in the other retina. 
 This relation and sympathy between cor- 
 responding points of the two retince, I do 
 not advance as an hypothesis, but as a 
 general fact or phsenomenon of vision. All 
 the pha;nomena before mentioned, of single 
 or double vision, lead to it, and are neces- 
 sary consequences of it. It holds true in- 
 variably in all perfect human eyes, as far 
 as I am able to collect from innumerable 
 trials of various kinds made upon my own 
 eyes, and many made by others at my de- 
 sire. Most of the hypotheses that have 
 been contrived to resolve the phtenomena 
 of single and d(3uble vision, suppose this 
 general fact, while their authors were not 
 aware of it. Sir Isaac Newton, who was 
 too judicious a philosopher, and too accu- 
 rate an observer, to have offered even a 
 conjecture whicli did not tally with the facts 
 that had fallen under his observation, pro- 
 poses a query with respect to the cause of 
 it — " Optics," Query, 15. The judicious 
 Dr Smith, in his " Optics," Book 1, § 137, 
 hath confirmed the truth of this general 
 phsenomenon from his own experience, not 
 only as to the apparent unity of objects 
 whose pictures fall upon the corresponding 
 points of the retina, but also as to the ap- 
 parent distance of the two appearances of 
 the same object when seen double.* 
 
 own eye, I can see either of these phacnomena, 
 under certain conditions, at will. Johannes Mueller, 
 Weber, Volkmann, and Heermann, are the most 
 recent observers. 1 may also notice, that the 
 congruence between the corresponding points (in 
 Reid's sense) of ihe two retinse, is admitted for the 
 perception of figure, but not for the sensations of 
 light and colour. — H. 
 
 • It might be proper here to say something ot the 
 Itrictures of Dr Wills on Reid's doctrine of single 
 vision ; but, as the matter is, after all, of no high 
 psychological importance, while the whole theory of 
 the form of the Horopter is, in consequence of 
 Mueller's observations, anew under discussion, I shall 
 
 This general phsenomenon appears, there- 
 fore, to be founded upon a very full induc- 
 tion, which is all the evidence we can have 
 for a fact of this nature. Before we make 
 an end of this subject, it will be proper to 
 inquire, First, Whether those animals whose 
 eyes have an adverse position in their heads, 
 and look contrary ways, have such corre- 
 sponding points in their retince ? Secondly, 
 What is the position of the corresponding 
 points in imperfect human eyes — I mean in 
 those that squint ? And, in the last place, 
 Whether this harmony of the correspond- 
 ing points in the retince, be natural and 
 original, or the effect of custom ? And, if 
 it is original. Whether it can be accounted 
 for by any of the laws of nature already 
 discovered ? or whether it is itself to be 
 looked upon as a law of nature, and a part 
 of the human constitution ? 
 
 Section XIV, 
 
 OF THE LAWS OF VISION IN BRUTE ANIMALS. 
 
 It is the intention of nature,in giving eyes 
 to animals, that they may perceive the 
 situation of visible objects, or the direction 
 in which they are placed— it is probable, 
 therefore, that, in ordinary cases, every 
 animal, whether it has many eyes or few, 
 whether of one structure or of another, sees 
 objects single, and in their true and proper 
 direction. And, since there is a prodigious 
 variety in the structure, the motions, and 
 the number of eyes in different animals and 
 insects, it is probable that the laws by 
 which vision is regulated, are not the same 
 in all, but various, adapted to the eyes which 
 nature hath given them. 
 
 Mankind naturally turn their eyes al- 
 ways the same way, so that the axes of the 
 two eyes meet in one point. They natur- 
 ally attend to, or look at that object only 
 which is placed in the point where the axes 
 meet. And whether the object be more or 
 less distant, the configuration of the eye is 
 adapted to the distance of the object, so as 
 to form a distinct picture of it. 
 
 When we use our eyes in this natural 
 way, the two pictures of the object we look 
 at are formed upon the centres of the two 
 retince ; and the two pictures of any con- 
 tiguous object are formed upon the points 
 of the retince which are similarly situate 
 with regard to the centres. Therefore, in 
 order to our seeing objects single, and in 
 their proper direction, with two eyes, it is 
 
 only refer the reader who is curious in such points, 
 to the following recent publications : — J. Mueller, 
 " Zur Verglcichenden Physiologic de Gesichtssin. 
 nes," &c., 18'26. — Volkmann, " Neue Beytraege zur 
 Physiologic des Gesichtssinnes," 183fi.— Heermann, 
 " UeberdieBilduDgder Ge6ichtsvorstellungcn,"&c., 
 1835— H.
 
 OF SEKIXG. 
 
 167 
 
 sufficient that we be so constituted, that 
 objects whose pictures are formed upon 
 the centres of the two reliita, or upon 
 points similarly situate with regard to these 
 centres, shall be seen in the same visi- 
 ble glace. And this is the constitution 
 which nature hath actually given to human 
 eyes. 
 
 When we distort our eyes from their 
 parallel direction, which is an unnatural 
 motion, but maj' be learned by practice ; or 
 when we direct the axes of the two eyes to 
 one point, and at the same time direct our 
 attention to some visible object much nearer 
 or much more distant than that point, which 
 is also unnatural, vet may be learned : in 
 these cases, and in these only, we see one 
 object double, or two objects confounded in 
 one. In these cases, the two pictures of 
 the same object are formed upon points of 
 the retince which are not similarly situate, 
 and so the object is seen double ; or the 
 two pictures of diflerent objects are formed 
 upon points of the retince which are simi- 
 larly situate, and so the two objects are 
 seen confounded in one place. 
 
 Thus it appears, that the laws of vision 
 in the human constitution are wisely adapted 
 to the natural use of human eyes, but not 
 to that use of them which is unnatural. We 
 see objects truly when we use our eyes in 
 the natural way ; but have false appearances 
 presented to us when we use them in a way 
 that is unnatur.il. We may reasonably 
 think that the case is the same with other 
 ammals. But is it not unreasonable to 
 think, that those animals which naturally 
 turn one eye towards oneobject, and another 
 eye towards another object, must thereby 
 have such false appearances presented to 
 them, as we have when we do so against 
 nature ? 
 
 Many animals have their eyes by nature 
 placed adverse and immoveable, the axes 
 of the two eyes being always directed to 
 opposite points. Do objects painted on the 
 centres of the two retime appear to such 
 animals as they do to human eyes, in one 
 and the same visible place ? I think it is 
 highly probable that they do not ; and that 
 they appear, as they really are, in opposite 
 places. 
 
 If we judge from analogy in this case, 
 it will lead us to think that tliere is a certain 
 correspondence between points of the two 
 retime in such animals, but of a different 
 kind from that which we have found in 
 human eyes. The centre of one retina will 
 correspond with the centre of the other, 
 in such manner that the objects whose 
 pictures are formed upon these correspond- 
 ing points, shall apiear not to be in the 
 same place, an in liinnan eyes, but in op- 
 posite places. An(l in the same manner 
 will the superior part of one retina corre- 
 
 spond with the inferior part of the other, 
 and the anterior part of one with the pos- 
 terior part of the other. 
 
 Some animals, by nature, turn their eyes 
 with equal facility, either the same way or 
 different ways, as we turn our hands and 
 arms. Have such animals corresponding 
 points in their retincB, and points which do 
 not correspond, as the human kind has ? 
 I think it is probable that they have not ; 
 because such a constitution in them could 
 serve no other purpose but to exhibit false 
 appearances. 
 
 If we judge from analogy, it will lead us 
 to think, that, as such animals move their 
 eyes in a manner similar to that in which 
 we move our arms, they have an inmiediate 
 and natural perception of the direction they 
 give to their eyes, as we have of the direc- 
 tion we give to our arms ; and perceive the 
 situation of visible objects by their eyes, in 
 a manner similar to that in which we per- 
 ceive the situation of tangible objects with 
 our hands. 
 
 We cannot teach brute animals to use 
 their eyes in any other way than in that 
 which nature hath taught them ; nor can 
 we teach them to communicate to us the 
 appearances which visible objects make to 
 them, either in ordinary or in extraordinary 
 cases. We have not, therefore, the same 
 means of discovering the laws of vision in 
 them, as in our own kind, but must satisfy 
 ourselves with probable conjectures ; and 
 what we have said upon this subject, is 
 chiefly intended to shew, that animals to 
 which nature hath given eyes differing in 
 their number, in theu* position, and in 
 their natural motions, may very probably 
 be subjected to different laws of vision, 
 adapted to the peculiarities of their organs 
 of vision. 
 
 Section XV. 
 
 SQUINTING CONSIDERED HYPOTHETICAL!, V. 
 
 Whether there be corresponding points 
 ill the rctinee of those who have an invo- 
 luntary squint ? and, if there are. Whether 
 they be situate in the same manner as in 
 those who have no squint ? are not ques- 
 tions of mere curiosity. They are of real 
 imjjortance to the physician who attempts 
 the cure of <a squint, and to the patient who 
 submits to the cure. After so much has 
 been said of the .straliistnus^ or scpiint, both 
 by medical and Ijy o])tic'al writers, one might 
 expect to find abundance of facts for deter- 
 mining these questions. Y<'t, I confivis, I 
 have been disappointed in this exj)ectation, 
 after taking some pains both to make ob- 
 servations, and to colli'ct those which have 
 been made b\' others.
 
 168 
 
 OF THE HUMAN MIND. 
 
 Nor will this appear very strange, if we 
 consider, that to make the observations 
 which arc necessary for determining these 
 questions, knowledge of the principles of 
 optics, and of the laws of vision, must 
 concur with opportunities rarely to be met 
 with. 
 
 Of those who squint, the far greater 
 part have no distinct vision with one eye.* 
 When this is the case, it is impossible, 
 and indeed of no importance, to determine 
 the situation of the corresponding points. 
 When both eyes are good, they commonly 
 differ so much in their direction, that the 
 same object cannot be seen by both at the 
 same time ; and, in this case, it will be 
 very difficult to determine the situation 
 of the corresponding points ; for such per- 
 sons will probably attend only to the ob- 
 jects of one eye, and the objects of the other 
 will be as little regarded as if they were not 
 seen. 
 
 We have before observed, that, when we 
 look at a near object, and attend to it, we 
 do not perceive the double appearances of 
 more distant objects, even when they are 
 in the same direction, and are presented 
 to the eye at the same time. It is probable 
 that a squinting person, when he attends to 
 the objects of one eye, will, in like manner, 
 have his attention totally diverted from the 
 objects of the other ; and that he will per- 
 ceive them as little as we perceive the 
 double appearances of objects when we use 
 our eyes in the natural way. Such a per- 
 son, therefore, unless he is so much a phi- 
 losopher as to have acquired the habit of 
 attending very accurately to the visible ap- 
 pearances of objects, and even of objects 
 which he does not look at, will not be able 
 to give any light to the questions now under 
 consideration. 
 
 It is very probable that hares, rabbits, 
 birds, and fishes, whose eyes are fixed in 
 an adverse position, have the natural fa- 
 culty of attending at the same time to vi- 
 sible objects placed in different, and even 
 in contrary directions ; because, without 
 this faculty, they could not have those ad- 
 vantages from the contrary direction of 
 their eyes, which nature seems to have in- 
 tended. But it is not probable that those 
 who squint have any such natural faculty ; 
 because we find no such faculty in the rest 
 of the species. We naturally attend to ob- 
 jects placed in the point where the axes of 
 the two eyes meet, and to them only. To 
 give attention to an object in a different di- 
 rection is unnatural, and not to be learned 
 without pains and practice. 
 
 * On this imperfection of vision ia rested the 
 theory of Squinting, proposed by Huftbn, and now 
 generally adopted. The defective eye is turned aside, 
 because, if it were directed to the object, together 
 with the perfect one, a confused iinprcssinn would 
 be produced — H. 
 
 A very convincing proof of this may btt 
 drawn from a fact now well known to phi- 
 losophers : when one eye is shut, there is 
 a certain space within the field of vision, 
 where we can see nothing at all — the space 
 which is directly opposed to that part of the 
 bottom of the eye where the optic nerve 
 enters. This defect of sight, in one part 
 of the eye, is common to all human eyes, 
 and hath been so from the beginning of the 
 world ; yet it was never known, until the 
 sagacity of the Abbe Mariotte discovered 
 it in the last century. And now when it is 
 known, it cannot be perceived, but by means 
 of some particular experiments, which re-^ 
 quire care and attention to make them 
 succeed. 
 
 What is the reason that so remarkable 
 a defect of sight, common to all mankind, 
 was so long unknown, and is now perceived 
 
 with so much difficulty ? It is surely this 
 
 That the defect is at some distance from 
 the axis of the eye, and consequently in a 
 part of the field of vision to which we never 
 attend naturally, and to which we cannot 
 attend at all, without the aid of some par- 
 ticular circumstances. 
 
 From what we have said, it appears, 
 that, to determine the situation of the cor- 
 responding points in the eyes of those who 
 squint, is impossible, if they do not see dis- 
 tinctly with both eyes ; and that it will be 
 very difficult, unless the two eyes differ so 
 little in their direction, that the same object 
 may be seen with both at the same time. 
 Such patients I apprehend are rare ; at 
 least there are very few of them with whom 
 I have had the fortune to meet : and there- 
 fore, for the assistance of those who may 
 have happier opportunities, and inclination 
 to make the proper use of them, we shall con- 
 sider the case of squinting, hypothetically, 
 pointing out the proper articles of inquiry, 
 the observations that are wanted, and the 
 conclusions that may be drawn from them. 
 1 . It ought to be inquired, Whether the 
 squinting person sees equally well with 
 both eyes ? and, if there be a defect in one, 
 the nature and degree of that defect ought 
 to be remarked. The experiments by which 
 this may be done, are so obvious, that I 
 need not mention them. But I would ad- 
 vise the observer to make the proper ex- 
 periments, and not to rely upon the testi- 
 mony of the patient ; because I have found 
 many instances, both of persons that squint- 
 ed, and others who were found, upon trial, 
 to have a great defect in the sight of one 
 eye, altliough they were never aware of it 
 before. In all the following articles, it is 
 supposed that the patient sees with both 
 eyes so well as to be able to read with 
 either, when the other is covered. 
 
 2. It oi.ight to be inquired. Whether, 
 when one eye is covered, the Other is turned
 
 OF SEEING. 
 
 160 
 
 directly to the object ? This ought to he 
 tried in both eyes successively. By this 
 observation, as a touchstone, we may try 
 the hypothesis concerning squinting, in- 
 vented by M. de la Hire, and adopted by 
 Boerhaave, and many others of the medical 
 faculty. 
 
 The h}-pothesis is, That, iu one eye of 
 a squniting person, the greatest sensibility 
 and the most distmct vision is not, as in 
 other men, iu the centre of the retina, but 
 upon one side of the centre ; and that he 
 turns the axis of this eye aside from the 
 object, in order that the picture of tlie object 
 may fall upon the most sensible part of the 
 retina, and thereby give the most distinct 
 vision. If this is the cause of squmting, 
 the squinting eye will be turned aside from 
 the object, when the other eye is covered, 
 as well as when it is not. 
 
 A trial so easy to be made, never was 
 made for more than forty years ; but the 
 hypothesis was very generally received — 
 so prone are men to invent hypotheses, 
 and so backward to examine them by facts. 
 At last, Dr Jurin having made the trial, 
 found that persons Vho s(juint turn the 
 axis of the squinting eye directly to the 
 object, when the other eye is covered. This 
 fact is confirmed by Dr Porterfield ; and I 
 have found it verified in all the instances 
 that have fallen under my observation. 
 
 3. It ought to be inquired. Whether the 
 axes of the two eyes follow one another, so 
 as to have always the same inclination, or 
 make the same angle, when the person 
 looks to the right or to the left, upward or 
 downward, or straight forward. By this 
 observation we may judge whether asquint 
 is owing to any defect iu the muscles which 
 move the eye, as some have supposed. In 
 the following articles, we suppose that the 
 inclination of the axes of the eyes is found 
 to be always the same. 
 
 4. It ouglit to be inquired, Whether the 
 person that squints sees an object single or 
 double ? 
 
 If he sees the object double, and if the 
 two appearances have an angular distance, 
 equal to the angle which the axes of his 
 eyes make with each other, it may be con- 
 cluded that he hath corre.sj}ondiiig ])oints in 
 the retince of his eyes, and that they have 
 the same situation as in those who have no 
 squint. If the two appearances should 
 have an angular distance which is always 
 the same, but manifestly greater or less 
 than the angle contained under the optic 
 axes, this would indicate corresponding 
 points in the re'.incB, whose situation Ls not 
 the saujc as in those who have no squint ; 
 but it is difficult to judge accurately of the 
 angle wiiich the optic axes make. 
 
 A squint.too small to be perceived, may 
 (iccJiHioM doiililc vision of objects : for, if we 
 
 speak strictly, every person squints more 
 or less, whose optic axes do not meet ex- 
 actly in the object which he looks at. Thus, 
 if a man can only bring the axes of his 
 eyes to be parallel, but cannot make them 
 converge in the least, he must have a small 
 squint iu looking at near objects, and will 
 see them double, while he sees very distant 
 objects single. Again, if the optic axes 
 always converge, so as to meet eight or ten 
 feet before the face at farthest, such a per- 
 son will see near objects single ; but when 
 he looks at very distant objects, he will 
 squint a little, and see them double. 
 
 An instance of this kind is related by 
 Aguilonius m his '* Optics," who says, that 
 he had seen a young man to whom near 
 objects appeared smgle, but distant objects 
 appeared double. 
 
 Dr Briggs, in his " Nova Visionis Theo- 
 ria," having collected from authors several 
 instances of double vision, quotes this from 
 Aguilonius, as the most wonderful and un- 
 accountable of all, insomuch that he sus- 
 pects some imposition on the part of the 
 young man : but to those who understand 
 the laws by which single and double vision 
 are regulated, it appears to be the natural 
 effect of a very small squint.' 
 
 Double vision may always be owing to a 
 small squint, when the two appearances 
 are seen at a small angular distance, 
 although no squint was observed : and I do 
 not remember any instances of double 
 vision recorded by authors, wherein any 
 account is given of the angular distance of 
 the appearances. 
 
 In almost all the instances of double 
 vision, there is reason to suspect a squint 
 or distortion of the eyes, from the concomi- 
 tant circumstances, which we find to be 
 one or other of the following — the approach 
 of death or of a ddiquixan, excessive drink- 
 ing or other intemperance, violent headache, 
 blistering the head, smoking tobacco, blows 
 or wounds in the head. In all these cases, 
 it is reasonable to suspect a distortion of 
 the eyes, cither from S])asm, or paralysis in 
 the muscles that move them, liut, although 
 it be probable that there is always a squint 
 greater or less where there is double vision, 
 yet it is certain that there is iu)t double 
 vision always where there is a squint. I 
 know no instance of double vision that con- 
 tinued for life, or even for a great number of 
 years. We shall therefore sup])ose, in the 
 following articles, that the squintuig person 
 sees objects single. 
 
 5. Tlie next inquiry, then, ought to be, 
 Whether the object is seen with both eyes 
 at the same time, or only with the eye 
 
 • It is observed l)y Piirkinjc and Volknmnn, fh.it 
 filiort.iiiKlitLiI persons, iinik'i ccrtuiii i-(iii<lii ions, tor 
 (list.int olijiilH dduliU'. Is llio r.isc I'l' Amiilcitiiuii 
 tiioritli:iii all cxntniplc "llliiv V - II
 
 170 
 
 OF THE HUMAN MIND. 
 
 whose axis is directed to it ? It hath been 
 taken for granted, by tlie writers upon the 
 strabismus, before Dr Jurin, that those who 
 squint commonly see objects single with 
 both eyes at the same time ; but I know 
 not one fact advanced by any writer which 
 proves it. Dr Jurin is of a contrary opi- 
 nion ; and, as it is of consequence, so it is 
 very easy, to determine this point, in parti- 
 cular instances, by this obvious experiment. 
 While the person that squints looks steadily 
 at an object, let the observer carefully re- 
 mark the direction of both his eyes, and 
 observe their motions ; and let an opaque 
 body be interposed between the object and 
 the two eyes successively. If the patient, 
 notwithstanding this interposition, and with- 
 out changing the direction of his eyes, con- 
 tiniies to see the object all the time, it may 
 be concluded that lie saw it with both eyes 
 at once. But, if the interposition of the 
 body between one eye and the object makes 
 it disappear, then we may be certain that it 
 was seen by that eye only. In the two 
 following articles, we shall suppose the first 
 to happen, according to the common hypo- 
 thesis. 
 
 6. Upon this supposition, it ought to be 
 inquired. Whether the patient sees an ob- 
 ject double in those circumstances wherein 
 it appears double to them who have no 
 squint ? Let him, for instance, place a 
 candle at the distance of ten feet ; and 
 holding his finger at arm's-length between 
 him and the candle, let him observe, when 
 he looks at the candle, whether he sees his 
 finger with both eyes, and whether he sees 
 it single or double ; and when he looks at 
 his finger, let him observe whether he sees 
 the candle with both eyes, and whether 
 single or double. 
 
 By this observation, it may be deter- 
 mined, whether to this patient, the phteno- 
 mena of double as well as of single vision 
 are the same as to them who have no squint. 
 If they are not the same — if he sees objects 
 single with two eyes, not only in the cases 
 wherein they appear single, but in those 
 also wlierein they appear double to other 
 men — the conclusion to be drawn from this 
 supposition is, that his single vision does not 
 arise from corresponding points in the re- 
 tinee of his eyes ; and that the laws of vision 
 are not the same in him as in the rest of 
 mankind. 
 
 7. If, on the other hand, he sees objects 
 double in those cases wlierein they appear 
 double to others, the conclusion must be, 
 that he hath corresponding points in the 
 retince of his eyes, but unnaturally situate. 
 And their situation may be thus determined. 
 
 When he looks at an object, having the 
 axis of one eye directed to it, and the axis 
 of the other turned aside from it, let us 
 suppose a right line to pass from the object 
 
 through the centre of the diverging eye. 
 We shall, for the sake of perspicuity, call 
 this right line, the natural axis of the eye ; 
 and it will make an angle with the real 
 axis, greater or less, according as his squint 
 is greater or less. We shall also call that 
 point of the retina in which the natural 
 axis cuts it, the natural cenire of the retina ; 
 which will be more or less distant from the 
 real centre, according as the squint is 
 greater or less. 
 
 Having premised these definitions, it will 
 be evident to those who understand the 
 principles of optics, that in this person the 
 natural centre of one retina corresponds 
 with the real centre of the other, in the 
 very same manner as the two real centres 
 correspond in perfect eyes ; and that the 
 points similarly situate with regard to the 
 real centre in one retina, and the natural 
 centre in the other, do lilcewise correspond, 
 in the very same manner as the points si- 
 milarly situate with regard to the two real 
 centres correspond in perfect eyes. 
 
 If it is true, as has been commonly af- 
 firmed, that one who squints sees an object 
 with both eyes at the same time, and j'et 
 sees it single, the squint will most probably 
 be such as we have described in this article. 
 And we may further conclude, that, if a 
 person affected with such a squint as we 
 have supposed, could be brought to the 
 habit of looking straight, his sight would 
 thereby be greatly hurt ; for he would 
 then see everything double which he saw 
 with both eyes at the same time ; and ob- 
 jects distant from one another would appear 
 to be confounded together. His eyes are 
 made for squinting, as much as those of 
 other men are made for looking straight ; 
 and his sight would be no less injured by 
 looking straight, than that of another man 
 by squinting. He can never see perfectly 
 when he does not squint, unless the corre- 
 sponding points of his eyes should by custom 
 change their place ; but how small the pro- 
 bability of this is will appear in the 17th 
 section. 
 
 Those of the medical faculty who attempt 
 the cure of a squint, would do well to con- 
 sider wliether it is attended with such symp- 
 toms as are above described. If it is, the 
 cure would be worse than the malady : for, 
 every one will readily acknowledge that it 
 is better to put up with the deformity of a 
 squint, than to purchase the cure by the 
 loss of perfect and distinct vision. 
 
 8. We shall noAV return to Dr Jurin's 
 hypothesis, and suppose that our patient, 
 when he saw objects single notwithstanding 
 his squint, was found, upon trial, to have 
 seen them only with one eye. 
 
 We would advise such a patient to en- 
 deavour, by repeated efforts, to lessen his 
 squint, and to bring the axes of his eyes
 
 OF SEEING. 
 
 171 
 
 nearer to a parallel direction. We have 
 naturally the power of niakinp; small varia- 
 tions in the inclination of the optic :ixes ; 
 and this power may be greatly increased by 
 exercise. 
 
 In the ordinary and natural use of our 
 eyes, we can direct their axes to a iixed 
 star ; in this case they must be parallel : 
 we can direct them also to an object six 
 inches distant from the eye ; and in this 
 case the axes must make an angle of fif- 
 teen or t^>enty degrees. We see young 
 people in their frolics learn to squint, malt- 
 ing their eyes either converge or diverge, 
 when they will, to a very considerable de- 
 gree. Why should it be more difficult for 
 a squinting person to leaiu to look straight 
 when he pleases ? If once, by an effort of 
 his will, he can but lessen his squint, fre- 
 quent practice will make it easy to lessen 
 it, and will daily increase his power. So 
 that, if he begins this practice in youth, and 
 perseveres in it, he may probably, after 
 some time, learn to direct both his eyes to 
 one object. 
 
 When he hath acquired this power, it 
 will be no difficult matter to determine, by 
 proper observations, whether the centres of 
 the retince, and other points simOarly situate 
 with regard to the centres, correspond, as 
 in other men. 
 
 9. Let us now suppose that he finds this 
 to be the case ; and that he sees an object 
 single with both eyes, when the axes of 
 both are directed to it. It will then concern 
 him to acquire the habit of looking straight, 
 as he hath got the power, because he will 
 thereby not only remove a deformity, but 
 improve his sight ; and I conceive this ha- 
 bit, like all others, may be got by frequent 
 exercise. He may practise before a mirror 
 when alone, and in company he ought to have 
 those about him who will observe and ad- 
 monish him wlien he squints. 
 
 10. \\'liat is sup])osed in the 9th article 
 is not merely imaginary ; it is really the 
 case of some squinting persons, as will 
 appear in the next section. Therefore, it 
 ought further to be inquired, How it comes 
 to pass that such a person sees an object 
 which he looks at, only with one eye, when 
 both are open ? In order to answer this 
 question, it may be observed, first, Whether, 
 when he looks at an object, the diverging 
 eye is not drawn so close to the nose, that it 
 can have no distinct images ? Or, secondly, 
 whether the pn])ilof the diverging eye is not 
 covered wholly, or in part, by the upper eye- 
 Lid ? Dr Jurin observed instances of these 
 c.'uses in persons that squinteil, and assigns 
 them as causes of their seeing the object 
 only with one eye. Thirdly, it may be 
 observeil, whether the diverging eye is not 
 80 directed, that the picture of tho. object 
 falls iipiin tli;it jiart of thorr/iim where the 
 
 optic nerve enters, and where there is no 
 vision ? This will probably happen in a 
 squmt wherein the axes of the eyes converge 
 so as to meet about six inches before the 
 nose. 
 
 11. In the last place, it ought to be 
 inquired. Whether such a person hath any 
 distinct vision at all with the diverging 
 eye, at the time he is looking at an object 
 with the other ? 
 
 It may seem very improbable that he 
 should be able to read with the diverging 
 eye when the other is covered, and yet, when 
 both are open, have no distinct vision with 
 it at all. But this, perhaps, will not appear 
 so improbable if the following considerations 
 are duly attended to. 
 
 Let us suppose that one who saw per- 
 fectly, gets, by a blow on the head, or some 
 other accident, a permanent and involun- 
 tary squint. According to the laws of vi- 
 sion, he will see objects double, and will see 
 objects distant from one another confounded 
 together ; but, such vision being very dis- 
 agreeable, as well as inconvenient, he will 
 do everything in his power to remedy it. 
 For alleviating such distresses, nature often 
 teaches men wonderful expedients, which 
 the sagacity of a philosopher would be un- 
 able to discover. Every accidental motion, 
 every direction or conformation of his eyes, 
 which lessens the evil, will be agreeable ; 
 it will be repeated until it be learned to 
 perfection, and become habitual, even with- 
 out thought or design. Now, in this case, 
 what disturbs the sight of one eye is the 
 sight of the other ; and all the disagreeable 
 appearances in vision would cease if the 
 light of one eye was extinct. The sight of 
 one eye will become more distinct and 
 more agreeable, in the same proportion as 
 that of the otlier becomes faint and in- 
 distinct. It may, therefore, be expected, 
 that every habit will, by degrees, be ac- 
 quired which tends to destroy distinct vi- 
 sion in one eye while it is preserved in the 
 other. These habits will be greatly facili- 
 tated if one eye was at first better than the 
 other ; for, in that case, the best eye will 
 always be directed to the object which he 
 intends to look at, and every habit will be 
 acquired which tends to hinder his seeing 
 it at all, or seeing it distinctly by the other 
 at the same time. 
 
 I shall mention one or two habits that 
 may probably be accpiired in such a case ; 
 perhaps there are others which we cannot 
 so easily conjecture. First, By a small in- 
 crease or diminution of his squint, he may 
 bring it to correspond with one or other of 
 the eases mentioned in the last article. 
 Secondly, The diverging eye may be brought 
 to such a conformation as to lie ertremely 
 8hort-sight(;d, and consecpiently to have no 
 distinct vision of objects at a distance
 
 172 
 
 OF THE HUMAN MIND. 
 
 knew this to be the case of one person that 
 squinted ; but cannot say whether the 
 short-sightedness of the diverging eye was 
 original, or acquired by habit. 
 
 We see, therefore, that one who squints, 
 and originally saw objects double by reason 
 of that squint, may acquire such habits 
 that, when he looks at an object, he shall 
 see it only with one eye ; nay, he may ac- 
 quire such habits that, when he looks at an 
 object with his best eye, he shall have no 
 distinct vision with the other at all. Whether 
 this is really the case — being unable to de- 
 termine in the instances that have fallen 
 under my observation — I shall leave to fu- 
 ture inquiry. 
 
 I have endeavoured, in the foregoing 
 articles, to delineate such a process as is 
 proper in observing the phtenoraena of 
 squinting. I know well by experience, that 
 this process appears more easy m theory, 
 than it will be found to be in practice ; 
 and that, in order to carry it on with success, 
 some qualifications of mind are necessary 
 in the patient, which are not always to be 
 met with. But, if those who have proper 
 opportunities and inclination to observe 
 such phaenomena, attend duly to this pro- 
 cess, they may be able to furnish facts less 
 vague and uninstructive than those we meet 
 with, even in authors of reputation. By 
 such facts, vain theories may be exploded, 
 and our knowledge of the laws of nature, 
 which regard the noblest of our senses, 
 enlarged. 
 
 Section XVI. 
 
 FACTS RELATING TO SQUINTING. 
 
 Having considered the phaenomena of 
 squinting, hypothetically, and their connec- 
 tion with corresponding points in the re- 
 tince. I shall now mention the facts I have 
 had occasion to observe myself, or have 
 met with in authors, that can give any light 
 to this subject. 
 
 Having examined above twenty persons 
 that squinted, I found in all of them a de- 
 fect in the sight of one eye. Four only 
 had so much of distinct vision in the weak 
 eye, as to be able to read with it, when the 
 other was covered. The rest saw nothing 
 at all distinctly with one eye. 
 
 Dr Porterfield says, tliat this is generally 
 the case of people that squint : and I sus- 
 pect it is so more generally than is com- 
 monly imagined. Dr Jurin, in a very 
 judicious dissertation upon squinting, 
 printed in Dr Smith's " Optics," observes, 
 that those who squint, and see with both 
 eyes, never sec the same object with both 
 at the same time; that, when one eye is 
 dircctfctl straight forward to mu object, the 
 
 other is drawn so close to the nose that the 
 object cannot at all be seen by it, the 
 images being too oblique and too indistinct 
 to affect the eye. In some squinting per- 
 sons, he observed the diverging eye drawn 
 under the upper eyelid, while the other 
 was directed to the object. From these 
 observations, he concludes that " che eye is 
 thus distorted, not for the sake of seeing 
 better with it, but rather to avoid seeing at 
 all with it as much as possible." From all 
 the observations he had made, he was satis- 
 fied that there is nothing peculiar in the 
 structure of a squinting eye ; that the fault 
 is only in its wrong direction ; and that 
 this wrong direction is got by habit. There- 
 fore, he proposes that method of cure which 
 we have described in the eighth and ninth 
 articles of the last section. He tells us, 
 that he had attempted a cure, after this 
 method, upon a young gentleman, with 
 promising hopes of success ; but was in- 
 terrupted by his falling ill of the small- 
 pox, of which he died. 
 
 It were to be wished that Dr Jurin had 
 acquainted us whether he ever brought the 
 young man to direct the axes of both eyes 
 to the same object, and whether, in that 
 case, he saw the object single, and saw it 
 with both eyes ; and that he had likewise 
 acquainted us, whether he saw objects 
 double when his squint was diminished. 
 But as to these facts he is silent. 
 
 I wished long for an opportunity of trying 
 Dr Jurin's method of curing a squint, with- 
 out finding one ; having always, upon ex- 
 amination, discovered so great a defect in 
 the sight of one eye of the patient as dis- 
 couraged the attempt. 
 
 But I have lately found three yoimg 
 gentlemen, with whom I am hopeful this 
 method may have success, if they have 
 patience and perseverance in using it. Two 
 of them are brothers, and, before I had 
 access to examine them, had been practis- 
 ing this method by the direction of their 
 tutor, with such success that the elder looks 
 straight when he is upon his guard : the 
 younger can direct both his eyes to one 
 object ; but they soon return to their usual 
 squint. 
 
 A third young gentleman, who had never 
 heard of this method before, by a few days 
 practice, was able to direct both his eyes to 
 one object, but could not keep thein long in 
 that direction. All the three agree in this, 
 that, when both eyes are directed to one ob- 
 ject, they see it and the adjacent objects 
 single ; but, when they squint, they see 
 objects sometimes single and sometimes 
 double. I observed of all the three, that 
 when they squinted most — that is, in the 
 way they had been accustomed to — the axes 
 of their eyes converged so as to meet five 
 or six inches before the nose. It is pro-
 
 OF SEEING. 
 
 173 
 
 bable that, in this case, the picture of the 
 object in the diverging eye, must fall upon 
 that part of the retina where the optic 
 nerve enters ; and, therefore, the object 
 could not be seen by that eye. 
 
 All the three have some defect in the 
 sight of one eye, which none of them knew 
 until I put them upon making trials ; and 
 when they squint, the best eye is always 
 directed to the object, and the weak eye is 
 that whicli diverges from it. But when the 
 best eye is covered, the weak eye is turned 
 directly to the object. Whether this defect 
 of sight in one eye, be the effect of its hav- 
 ing been long disused, as it must have been 
 when they squinted ; or whether some ori- 
 ginal defect in one eye might be the occasion 
 of their squinting, time may discover. The 
 two brothers have found the sight of the 
 weak eye improved by using to read with it 
 while the other is covered. The elder can 
 read an ordinary print with the weak eye ; 
 the other, as well as the third gentleman, 
 can only read a large print with tlie weak 
 eye. I have met with one other person 
 only who squinted, and yet could read a 
 large print with the weak eye. He is a 
 young man, whose eyes are both tender and 
 weak-sighted, but the left much weaker than 
 the right. When he looks at any object, 
 he always directs the right eye to it, and 
 then the left is turned towards the nose so 
 much that it is impossible for him to see 
 the same object with both eyes at the same 
 time. When the right eye is covered, he 
 turns the left directly to the object ; but he 
 sees it indistinctly, and as if it had a mist 
 about it. 
 
 I made several experiments, some of them 
 in the company and with the assistance of 
 an ingenious physician, in order to discover 
 whether objects that were in the axes of the 
 two eyes, were seen in one ])lace confounded 
 together, as in those who have no involun- 
 tary squint. The object placed in the axis 
 of the weak eye was a liglitcd candle, at the 
 distance of eight or ten feet. Before the 
 otlier eye was placed a printed book, at such 
 a distance as that he could read upon it. 
 He Faid, that while he read upon the book, 
 he saw the candle but very faintly. And 
 from what we could learn, these two objects 
 did not api)ear in one place, but h.Td all that 
 angular distance in appearance which they 
 had in reality.* 
 
 If this was really the case, the conclusion 
 to be drawn from it is, that the correspond- 
 ing points in )iis eyes are not situate in the 
 same ni;iniier as in other men ; and that, if 
 ho could be brought to direct botli eyes to 
 one object, he would see it doul)le. But, 
 considering that tlie young man bad never 
 been accustomed to observations of this 
 
 « Sec VVolU— C'<Ti70 EH(ay8,"Xc.,i). ?a)— 11. 
 
 kind, and that the sight of one eye was so 
 imperfect, I do not pretend to draw this 
 conclusion with certainty from this single 
 instance. 
 
 All that can be inferred from these facts 
 is, that, of four persons who squint, three 
 appear to have nothing preternatural in the 
 structure of their eyes. The centres of their 
 retincB, and the points similarly situate with 
 regard to the centres, do certainly corre- 
 spond in the same manner as in other men 
 
 so that, if they can be brought to the habit 
 of directing their eyes right to an object, 
 they will not only remove a deformity, but 
 improve their sight. With regard to the 
 fourth, the case is dubious, with some pro- 
 bability of a deviation from the usual course 
 of nature in the situation of the correspond- 
 ing points of his eyes. 
 
 Section XVII. 
 
 OF THE EFFECT OF CUSTOM IN SEEING CBJECTS 
 SINGLE. 
 
 It appears from the phsenomena of single 
 and double vision, recited in § 13, that 
 our seeing an object single with two eyes, 
 depends upon these two things : — First, 
 Upon that mutual correspondence of certain 
 points of the retina which we have often 
 described ; Secondly, Upon the two eyes 
 being directed to the object so accurately 
 that the two images of it fall upon corre- 
 sponding points. These two things must 
 concur in order to our seeing an object 
 single with two eyes ; and, as far as they 
 depend upon custom, so far only can suigle 
 vision depend upon custom. 
 
 With regard to the second — that is, the 
 accurate direction of both eyes to the ob- 
 ject — I think it must be acknowledged 
 that this is only learned by custom. Na- 
 ture hath wisely ordained tlie eyes to move 
 in such manner that their axes shall 
 always be nearly parallel ; but hath left it 
 in our power to vary their inclination a 
 little, according to the distance of the ob- 
 ject we look at. Without this power, 
 objects would appear single at one jnirti- 
 cular distance only ; and, at disfances much 
 less or much greater, would always appear 
 double. The wisdom of nature is conspi- 
 cuous in giving us this power, and no less 
 conspicuous in making the extent of it ex- 
 actly adequate to the end. 
 
 The jiarallelism of the eyes, in general, 
 is therefore the work of nature ; liut that 
 precise aijd accurate direction, which must 
 be varied according <o the distance of the 
 object, is the elleet of custom. Tlie ])()wer 
 which nature hath left us of varying tiie 
 inclination of the optic axes a little, iH 
 turned into a habit of giving (hem alwiiyH
 
 174 
 
 OF THE HUMAN MIND. 
 
 that inclination which is adapted to tho 
 distance of the object. 
 
 But it may be asked, What gives rise to 
 this habit ? The only answer that can be 
 given to this question is, that it is found 
 necessary to perfect and distinct vision. A 
 man who hath lost the sight of one eye, 
 very often loses the habit of directing it 
 exactly to the object he looks at, because 
 that habit is no longer of use to him. And 
 if he should recover the sight of his eye, 
 he would recover this habit, by finding it 
 useful. No part of the human constitution 
 is more admirable than that whereby we 
 acquire habits which are found useful, with- 
 out any design or intention. Children 
 must see imperfectly at first ; but, by using 
 their eyes, they learn to use them in the 
 best manner, and acquire, without intend- 
 ing it, the habits necessary for that pur- 
 pose. Every man becomes most expert in 
 that kind of vision which is most useful to 
 him in his particular profession and man- 
 ner of life. A miniature painter, or an 
 engraver, sees very near objects better than 
 a sailor ; but the sailor sees very distant 
 objects much better than they. A person 
 that is short-sighted, in looking at distant 
 objects, gets the habit of contracting the 
 aperture of his eyes, by almost closing his 
 eyelids. Why ? For no other reason, 
 but because this makes him see the object 
 more distinct. In like manner, the reason 
 why every man acquires the habit of direct- 
 ing both eyes accurately to the object, must 
 be, because thereby he sees it more per- 
 fectly and distinctly. 
 
 1 1 remains to be considered, whether that 
 correspondence between certain points of 
 the retinee, which is likewise necessary to 
 single vision, be the effect of custom, or an 
 original property of human eyes. 
 
 A strong argument for its being an ori- 
 ginal property, may be drawn fi"om the 
 habit, just now mentioned, of directing the 
 eyes accurately to an object. This habit 
 is got by our finding it necessary to perfect 
 and distinct vision. But why is it neces- 
 sary ? For no other reason but this, be- 
 cause thereby the two images of the object 
 falling upon corresponding points, the eyes 
 assist each other in vision, and the object 
 is seen better by both together, than it 
 could be by one ; but when the eyes are not 
 accurately directed, the two images of an 
 object fall upon points that do not corre- 
 spond, whereby the sight of one eye disturbs 
 the sight of the other, and the object is 
 seen more indistinctly with both eyes than 
 it would be with one. Whence it is rea- 
 sonable to conclude, that this correspond- 
 ence of certain points of the retinee, is prior 
 to the habits we acquire in vision, and con- 
 sequently is natural and original. We have 
 all acquired the habit of directing our eyes 
 
 always in a particular manner, which causes 
 single vision. Now, if nature hath ordained 
 that we should have single vision only, when 
 our eyes are thus directed, there is an ob- 
 vious reason why all mankind should agree 
 in the habitoi' directing them in this manner. 
 But, if single vision is the effect of custom, 
 any other habit of directing the eyes would 
 have answered the purpose ; and no account 
 can be given why this particular habit should 
 be so universal ; and it must appear very 
 strange, that no one instance hath been 
 found of a person who had acquired the 
 habit of seeing objects single with both eyes, 
 while they were directed in any other man- 
 ner.* 
 
 The judicious Dr Smith, in his excellent 
 system of optics, maintains the contrary 
 opinion, and offers some reasonings and 
 facts in proof of it. He agrees with Bishop 
 Berkeleyt in attributing it entirely to cus- 
 tom, that we see objects single with two eyes, 
 as well as that we see objects erect by in- 
 verted images. Having considered Bishop 
 Berkeley's reasonings in the 1 1th section, 
 we shall now beg leave to make some 
 remarks on what Dr Smith hath said upon 
 this subject, with the respect due to an 
 author to whom the world owes, not only 
 many valuable discoveries of his own, but 
 those of the brightest mathematical genius 
 of this age, which, with great labour, he 
 generously redeemed from oblivion. 
 
 He observes, that the question, Why we 
 see objects single with two eyes ? is of the 
 same sort with this. Why we hear sounds 
 single with two ears ? — and that the same 
 answer must serve both. The inference 
 intended to be drawn from this observation 
 is, that, as the second of these phsenomena 
 is the effect of custom, so likewise is the 
 first. 
 
 Now, I humbly conceive that the ques- 
 tions are not so much of the same sort, 
 that the same answer must serve for 
 both ; and, moreover, that our hearing 
 single with two ears, is not the effect of 
 custom. 
 
 * This objection did not escape Dr Smith himself; 
 but Rcid seems to have overlooked his answer. 
 " When we view," he says, " an object steadily, we 
 have acquired a habit of directing the optic axes to 
 the point in view ; because its pictures, falling upon 
 the middle points of the retinas, are then distincier 
 than if they fell upon any other places ; and, since 
 the pictures of the whole object are equal to one 
 another, and are both inverted with respect to the 
 op'ic axes, it follows that the pictures of any col- 
 lateral point are painted upon corresponding points of 
 the retinas." 
 
 This answer is rendered more plausible from the 
 subsequent anatomical discovery of Soemmering. 
 He found that, in that part of the retina « hich lies 
 at the axis of the eye, there is, in man, and in other 
 animals of acute vision, an opening, real or appar. 
 ent, (foramen centrale,) the dimensions of which 
 are such that the images of distincter vision would 
 seem to be enclosed within it. — H. 
 
 f This is an inadvertency. Berkeley hazards no 
 such opinion in any of his works.— H.
 
 OF SEEING. 
 
 175 
 
 Two or more visible objects, although 
 perfectly similar, and seen at the very same 
 time, may be distinguished by their visible 
 places ; but two sounds perfectly similar, 
 and heard at the same time, cannot be dis- 
 tinguished ; for, from the nature of sound, 
 the sensations they occasion must coalesce 
 into one, and lose all distinction. If, there- 
 fore, it is asked, Wliy we hear sounds single 
 with two ears ? I answer. Not from custom ; 
 but because two sounds which are perfectly 
 like and synchronous, have nothing by 
 which they can be distinguished. But will 
 this answer fit the other question ? I thmk 
 not. 
 
 The object makes an appearance to each 
 eye, as the sound makes an impression upon 
 each ear : so far the two senses agree. But 
 the visible appearances may be distin- 
 guished by place, when perfectly like in other 
 respects ; the sounds cannot be thus dis- 
 tinguished : and herein the two senses dif- 
 fer. Indeed, if the two appearances have 
 the same visible place, they are, in that 
 case, as incapable of distinction as the sounds 
 were, and we see the object single. But 
 when they have not the same visible place, 
 they are perfectly distinguishable, and we 
 see the object double. We see the object 
 single only, when the eyes are directed in 
 one particular manner; while there are many 
 other waj's of directing them within the 
 sphere of our power, by which we see the 
 object double. 
 
 Dr Smith justly attributes to custom that 
 well-known fallacy in feeling, whereby a 
 button pressed with two opposite sides of 
 two contiguous fingei-s laid across, is felt 
 double. I agree with him, that the cause 
 of this appearance is, that those opposite 
 sides of the fingers have never been used 
 to feel the same object, but two different 
 objects, at the same time. And I beg leave 
 to add, that, as custom produces this ph;c- 
 nomenon, so a contrary custom destroys it ; 
 for, if a man frequently accustoms himself 
 to feel the button with his fingers across, it 
 will at last be felt single ; as I have found 
 by experience. 
 
 It may be taken for a general rule, that 
 things which are produced by custom, may 
 be undone or changed by disuse, or by a 
 contrary custom. On the other hand, it 
 is a strong argument, that an effect is not 
 owing to custom, but to the constitution 
 of nature, wlien a contrary custom, long 
 continued, is found neither to change nor 
 weaken it. I take this to lie the best rule 
 by which we can determine the ((uestion 
 presently* uii<l<'r consiileratioii. 1 shall, 
 tlierefore, meiiti n two facts Itrouglit liy 
 Dr Smitli, to jirove that tiic corrcsjionding 
 points of the relince have been changed hy 
 
 % See note » at p tli;, a. — II. 
 
 custom ; and then I shall mention soma 
 facts tending to prove, that there are cor- 
 responding points of the retime of the eyes 
 originally, and that custom produces no 
 change in them. 
 
 " One fact is related upon the authority 
 of Martin Folkes, Esq., who was informed 
 by Dr Hepburn of Lynn, that the Ixev. Mr 
 Foster of Clinchwharton, in that neighbour- 
 hood, having been blind for some years of a 
 ffulta sercua, was restored to sight by sali- 
 vation ; and that, upon his first beginnmg 
 to see, all objects appeared to him double ; 
 but afterwards, the two appearances ap- 
 proaching by degrees, he came at last to 
 see single, and as distinctly as he did before 
 he was blind." 
 
 Upon this case, I observe. First, That it 
 does not prove any change of the corre- 
 sponding points of the eyes, unless we sup- 
 pose, what is not aflirmed, that Mr Foster 
 directed his eyes to the object at first, wlien 
 he saw double, with the same accuracy, and 
 in the same manner, that he did afterwards, 
 when he saw single. Secondly, If we should 
 suppose this, no account can be given, why 
 at first the two appearances should be seen 
 at one certain angular distance rather than 
 another ; or why this angular distance should 
 gradually decrease, until at last the appear- 
 ances coincided. How could this effect be 
 produced by custom ? But, Thirdly, Every 
 circumstance of this case may be accounted 
 for on the supposition that Mr Foster had 
 corresponding points in the rcthits of his 
 eyes from the time he began to see, and that 
 custom made no change with regard to them. 
 We need only further suppose, what is 
 common in such cases, that, by some years' 
 blindness, he had lost the habit of directing 
 his eyes accurately to an object, and that he 
 gradually recovei-ed this habit when he came 
 to see. 
 
 The second fact mentioned by Dr Smith, 
 is taken from JMr Cheselden's " Anatomy," 
 and is this : — ■' A gentleman who, from .1 
 blow on the head, had one eye distorted, 
 found every object appear double; but, by de- 
 grees, the most familiar ones became single ; 
 and, in time, all objects became so, without 
 any amendment of the distortion." 
 
 I observe here, that it is not said that 
 the two appearances gradually apjiroached, 
 and at last united, without any aniendment 
 of the distortion. This would indeed have 
 been a decisive jtroof of a change in the 
 corresponding points of the retitifp, and yet 
 of such a change as could not be accounted 
 for from custom. But this is not said ; and, 
 if it had boon observed, a circnmsfance so 
 romarliable would have been mentioned by 
 I\rr Chcsclden, as it was in the other ca.so 
 by Dr llc|pliuni. We may, therefore, tako 
 it for granted, that one of the appearances 
 vanished Ijy degrees, witiiout approaching to
 
 176 
 
 OF THE HUMAN MIND. 
 
 the other. And this I conceive might hap- 
 pen several ways. First, The sight of tlic 
 distorted eye might gradually decay by the 
 hurt ; so the appearances presented by that 
 eye would gradually vanish. Secondly, A 
 small and un perceived change in the man- 
 ner of directing the eyes, miglit occasion 
 his not seeing the object wiih the dis- 
 torted eye, as appears from § 15, Art. 10. 
 Thirdly, By acquiring the habit of direct- 
 ing one and the same eye always to the ob- 
 ject, the faint and oblique appearance pre- 
 sented by the other eye, might be so little 
 attended to when it became familiar, as not 
 to be perceived- One of these causes, or 
 more of them concurring, might produce 
 the effect mentioned, without any change of 
 the corresponding points of the eyes. 
 
 For these reasons, the facts mentioned 
 by Dr Smith, although curious, seem not 
 to be decisive. 
 
 The following facts ought to be put in 
 the opposite scale. First, in the famous 
 case of the young gentleman couched by Mr 
 Cheselden, after having had cataracts on 
 both eyes until he was [above] tliirteen years 
 of ago, it appears that he saw objects single 
 from the time he began to see with both 
 eyes. Mr Cheselden's words are, "And 
 now, being lately couched of his other eye, 
 he says, that objects, at first, appeared 
 large to this eye, but not so large as they 
 did iit first to the other ; and, looking upon 
 the same object with both eyes, he thought 
 it looked about twice as large as with the 
 first couched eye only, but not double, that 
 we can anywise discover." 
 
 Secondly, The three young gentlemen 
 mentioned in the last section, who had 
 squinted, as far as I know, from infancy, 
 as soon as they learned to direct both eyes to 
 an object, saw it single. In these four cases, 
 it appears evident that the centres of the 
 retlncB corresponded originally, and before 
 custom could produce any such effect ; for 
 Mr Cheselden's young gentleman had never 
 been accustomed to see at all before he was 
 couched ; and the other three had never 
 been accustomed to direct the axes of both 
 eyes to the object. 
 
 Thirdly, from the facts recited in § 13, 
 it appears, that, from the time we are 
 capable of observing the phfenomena of 
 single and double vision, custom makes no 
 change in them. 
 
 I have amused myself with such observ- 
 ations for more than thirty years ; and in 
 every case wherein I saw the object double 
 at first, I see it so to this day, notwith- 
 standing the constant experience of its being 
 single. In other cases, where I know there 
 are two objects, there appears only one, 
 after thousands of experiments. 
 
 Let a man look at a familiar object 
 through a polyhedron, or niultiplyiug-glass, 
 
 every hour of his life, the number of visible 
 appearances will be the same at last as at 
 first ; nor does any number of experiments, 
 or length of time, make the least change. 
 
 Effects produced by habit, must vary 
 according as the acts by which the habit is 
 acqu red are more or less frequent ; but 
 the pha3nomena of single and double vision 
 are so invariable and uniform in all men, 
 are so exactly regulated by mathematical 
 rules, that I think we have good reason to 
 conclude that they are not the effect of cus- 
 tom, but of fixed and immutable laws of 
 nature. 
 
 Section XVIII. 
 
 OF DR PORTERFIELD's ACCOUNT OF SINGLE 
 AND DOUBLE VISION. 
 
 Bishop Berkeley and Dr Smith seem to 
 attribute too much to custom in vision, Dr 
 Porterfield too little. 
 
 This ingenious writer thinks, that, by an 
 original law of our nature, antecedent to 
 custom and experience, we perceive visible 
 objects in their true place, not only as to 
 their direction, but likewise as to their dis- 
 tance from the eye ; and, therefore, he 
 accounts for our seeuig objects single, with 
 two eyes, in this manner. Having the 
 faculty of perceiving the object with each 
 eye in its true place, we must perceive it 
 with both eyes in the same place ; and, 
 consequently, must perceive it single. 
 
 He is aware that this principle, although 
 it accounts for our seeing objects single 
 with two eyes, yet does not at all account 
 for our seeing objects double ; and, whereas 
 other writers on this subject take it to be a 
 sufficient cause for double vision that we 
 have two eyes, and only find it difficult to 
 assign a cause for single vision, on the 
 contrary, Dr Porterfield's principle throws 
 all the difficulty on the other side. 
 
 Therefore, in order to account for the 
 phsenomena of double vision, he advances 
 another principle, without signifying whe- 
 ther he conceives it to be an original law of 
 our nature, or the effect of custom. It is. 
 That our natural perception of the distance 
 of objects from the eye, is not extended to 
 all the objects that fall within the field of 
 vision, but limited to that which wo directly 
 look at ; and that the circumjacent objects, 
 whatever be their real distance, are seen at 
 the same distance with the object we look 
 at ; as if they were all in the surface of a 
 sphere, whereof the eye is the centre. 
 
 Thus, single vision is accounted for by 
 our seeing the true distance of an object 
 which we look at ; and double vision, by a 
 false appearance of distance in objects 
 which we do not directly look at.
 
 OF SEEING. 
 
 177 
 
 We agree with this learned and inge- 
 nious author, that it is by a natural and 
 original principle that we see visible objects 
 hi a certain direction from the eye, and 
 honour him as the author of this discovery :" 
 but we cannot assent to either of those 
 principles by which lie explains single and 
 double vision —for the following reasons : — 
 
 1. Our having a natural and original 
 perception of the distance of objects from 
 the eye, appears contrary to a weil-attested 
 fact : for the young gentleman couched by 
 Mr Cheselden imagined, at first, that what- 
 ever he saw touched his eye, as what he 
 felt touched his hand.-j- 
 
 2. The perception we have of the distance 
 of objects from the eye, whether it be from 
 nature or custom, is not so accurate and 
 determinate as is necessary to produce sin- 
 gle vision. A mistake of the twentieth or 
 thirtieth part of the distance of a small 
 object, such as a pin, ouglit, according to 
 Dr Porterfield's hypothesis, to make it ap- 
 pear double. Very few can judge of the 
 distance of a visible object with such 
 accuracy. Yet we never find double vision 
 produced by mistaking the distance of the 
 object. There are many cases in vision, 
 even with the naked eye, wherein we mis- 
 take the distance of an object by one half 
 or more : why do we see such objects single ? 
 When I move my spectacles from my eyes 
 toward a small object, two or three feet dis- 
 tant, the object seems to approach, so as to 
 be seen at last at about half its real distance ; 
 but it is seen single at that apparent distance, 
 
 * To this honour Portcrfie'dhas no title. The law 
 oithf line of visible direction, was a. common tlieory 
 long before the publication of his writings; tor it was 
 maintained by Kepler, Gas^en(li, Schemer, Kohault, 
 Regi-, Du Hamel, Mariotte, De ("hales, Miisschen. 
 broek, Mnlyncux, &c. &c., and mnttt/ of these main- 
 tain! d that this law was an original principW or in. 
 ttitiition of our nature. — H 
 
 t We must be careful not, like Reid and^jihilo- 
 sovihers in general, to confound ihe perceptions of 
 mcTe extfrnality oT outness, and the knowl' djjewe 
 havo cf iistancr, through tlieeye. 'I'he former may 
 be, and probably is, natural; ^hUe the lattrr, in a 
 great but uiiappretiable measure, is acquired. In the 
 case of t iRselden— that in which the blindness pre- 
 vious to the recovery o' sight was most pertict, and, 
 therefore, the m t instrnc ivc ui)on record — ihc 
 patient, thong i he h.id little or n ■ jiercciition of 
 distance, i. e ot the degree of externality, had still 
 a perception of that cxtemaliiy absolutely The 
 object-, II Slid, seemed to " tuucli his eyes, ai what 
 helelt dill his skin ;" hut they did not appiar to hnn 
 a» if ill his eyes, far less as a mere allection of the i r. 
 gan. '1 hi<, however, is err<)neou>ly assumed by Mr 
 Fearn. 'I his natural perception of Outiie.s, which 
 is the loundaiion of our acquired knowledge ot (lis- 
 taiice, semis given us in Ihe-naliiral perci ption we 
 have ot the direction of the rays ot light. 
 
 In like manner, we must i ot contbuiid, as is com- 
 monly done, ti'Cfaci of thee\e .dfiirding us a per. 
 ception of extension and jilain Jtunre, or outline, 
 in the perception <i/roliiurs, and the (act of iig beirit; 
 the vehicle of iiiliiiiatinris in regard to the con, pa 
 ralive magnitude and cnbical fnrms of the objects 
 Irorn wh.cli ihe,e rays pmcied. 1 he one i* a know. 
 >e<lgo by K'n'C— natural, inimedi.ite, and iifallihle ; 
 the other, like thai ol distance, is, by infeicnce, ac. 
 quired, mediate, and at best iilwayi nitecure.— H. 
 
 as well as when we see it with the naked 
 eye at its real distance. And when we look 
 at an object with a binocular telescope, pro- 
 perly fitted to the eyes, we see it single, 
 while it appears fifteen or twenty times 
 nearer tlian it is. Tliere are then few cases 
 wherein the distance of an object from the 
 eye is seen so accurately as is necessary for 
 single vision, upon this hypothesis : this 
 seems to be a conclusive argument against 
 the account given of single vision. We find, 
 likewise, that false judgments or fahacious 
 appearances of the distance of an object, do 
 not produce double vision : this seems to 
 be a conclusive argument against the account 
 given of double vision. 
 
 3. The perception we have of the linear 
 distance of objects seems to be wlioUy the 
 effect of experience. This, I think, hath 
 been proved by Bishop Berkeley and by 
 Dr Smith ; and when we come to point out 
 the means of judging of distance by sight, 
 it will appear that they are all furnished by 
 experience. 
 
 4. Supposing that, by a law of our nature, 
 the distance of objects from the eye were 
 perceived most accurately, as well as their 
 direction, it will not follow that we must 
 see the object single. Let us consider what 
 means such a law of nature would furnish 
 for resolving the question. Whether the 
 objects of the two eyes are in one and the 
 same place, and consequently are not two, 
 but one ? 
 
 Suppose, then, two right lines, one drawn 
 from the centre of one eye to its object, the 
 other drawn, in like manner, from the centre 
 of the other eye to its object. This law of 
 nature gives us the direction or position of 
 each of these right lines, and the length of 
 each ; and tliis is all that it gives. These 
 are geometrical data, and we may learn from 
 geometry what is determined by their means. 
 Is it, then, determined by these data, Whe- 
 ther the two right lines terminate in one 
 and the same point, or not ? No, truly. 
 In order to determine this, we must liave 
 three otlier data. We must know whether 
 the two right lines arc in one plane ; we 
 nuist know what angle tliey make ; and we 
 must know the distance between the centres 
 of the eyes. And when tlRse things are 
 known, we must ajiply the rules of trigono- 
 metry, before wc can resolve the question, 
 Whetlior the olijeets of the two eyes are in 
 one and the same iilace ; and, consequently, 
 whether they are two or one ? 
 
 5. That fnlse appearance of distance into 
 which double vision is resolved, caiiinit bo 
 the effect of custom, for constant expcrienci: 
 contradicts it. Neitlier hath it the I'eiiture.') 
 of a law of nature, becau.se it does not 
 answer any good purpo.se, nor, indeed, any 
 purpose at all, but to deceive us. But wliy 
 should we seek for .'irgmiiciitR, in a (nicslinn 
 
 .N
 
 178 
 
 OF THE HUMAN MIND. 
 
 concerning what appears to us, or does not 
 appear ? The question is, At what distance 
 do the objects now in my eye appear ? Do 
 they all a|)pear at one distance, as if placed 
 in the concave surface of a sphere, the eye 
 being in the centre ? Every man, surely, 
 may know this with certainty ; and, if he 
 will but give attention to the testimony of 
 his eyes, needs not ask a philosopher how 
 visible objects appear to him. Now, it is 
 very true, that, if I look up to a star in the 
 heavens, the other stars that appear at the 
 same time, do appear in this manner : yet 
 this j)hienomcnon does not favour Dr Por- 
 terfield's hypothesis ; for the stars and 
 heavenly bodies do not appear at their true 
 distances when we look directly to them, 
 any more than when they are seen obliquely : 
 a'ld if this phainonienon be an argument for 
 Dr Po/toriield's second princij)le, it must 
 destroy the first. 
 
 The true cause of this phsenomenon will 
 be given afterwards ; therefore, setting it 
 aside for the present, let us put another 
 case. I sit in my room, and direct my 
 eyes to the door, which appears to be 
 about sixteen feet distant : at the same 
 time, I see many other objects faintly and 
 obliquely — the floor, floor-cloth, the table 
 whicli I write upon, papers, standish, 
 candle, &c. Now, do all these objects ap- 
 pear at the same distance of sixteen feet ? 
 Upon the closest attention, I find they do 
 not. 
 
 Section XIX. 
 
 of dr briggs's theory, and sir isaac 
 Newton's conjecture on this sub- 
 ject, 
 
 I am afraid the reader, as well as the 
 writer, is already tired of the subject of 
 single and double vision. The multitude 
 of theories advanced by authors of great 
 name, and the multitude of facts, observed 
 without sufficient skill in optics, or related 
 without attention to the most material and 
 decisive circumstances, have equally contri- 
 buted to perplex it. 
 
 In order to bring it to some issue, I have, 
 in the 13th section, given a more full 
 and regular deduction than had been given 
 heretofore, of the phtenoraena of single and 
 double vision, in those whose sight is per- 
 fect ; and have traced them up to one ge- 
 neral principle, which appears to be a law 
 of vision in human eyes that are perfect and 
 in their natural state. 
 
 In the I4th section, I have made it ap- 
 pear, that this law of vision, although ex- 
 cellently adapted to the fabric of human 
 eyes, cannot answer the purposes of vision 
 in some other animals ; and therefore, very 
 
 probably, is not common to all animals. 
 The purpose of the 15th and 16th sections 
 is, to inquire. Whether there be any de- 
 viation from this law of vision in those 
 who squint ? — a question which is of real 
 importance in the medical art, as well as 
 in the philosophy of vision ; but which, 
 after all that hath been observed and 
 written on the subject, seems not to be 
 ripe for a determination, for want of pro- 
 per observations. Those who have had 
 skill to make proper observations, have 
 wanted opportunities ; and those who have 
 had opportunities, have wanted skill or 
 attention. I have therefore thought it 
 worth Avhile to give a distinct account of 
 the observations necessary for the deter- 
 mination of this question, and what con- 
 clusions may be drawn from the facts ob- 
 served. I have likewise collected, and set 
 in one view, the most conclusive facts that 
 have occurred in authors, or have fallen 
 under my own observation. 
 
 It must be confessed that these facts, 
 when applied to the question in hand, make 
 a very poor figure ; and the gentlemen of 
 the medical faculty are called upon, for the 
 honour of their profession, and for the bene- 
 fit of mankind, to add to them. 
 
 All the medical, and all the optical writers 
 upon the strabismus that I have met with, 
 except Dr Jurin, either affirm, or take it 
 for granted, that squinting persons see the 
 object with both eyes, and yet see it single. 
 Dr Jurin affirms that squinting persons 
 never see the object with both eyes ; and 
 that, if they did, they would see it double. 
 If the common opinion be true, the cure of 
 a squint would be as pernicious to the sight 
 of the patient, as the causing of a perma- 
 nent squint would be to one who naturally 
 liad no squint ; and, therefore, no physi- 
 cian ought to attempt such a cure, no 
 patient ought to submit to it. But, if Dr 
 Jurin 's opinion be true, most young people 
 that squint may cure themselves, by taking 
 some pains ; and may not only remove the 
 deformity, but, at the same time, improve 
 their sight. If the common opinion be 
 true, the centres, and other points of the two 
 retince, in squintuig persons, do not corre- 
 spond, as in other men, and Nature, in them, 
 deviates from her common rule. But, if 
 Dr Jurin 's opinion be true, there is reason 
 to think that the same general law of vision 
 which we have found in perfect human eyes, 
 extends also to those which squint. 
 
 It is impossible to determine, by reason- 
 ing, which of these opinions is true ; or 
 whether one may not be found true in some 
 patients, and the other in others. Here, 
 experience and observation are our only 
 guides ; and a deduction of instances is the 
 only rational argument. It might, there- 
 fore, have been exnected, that the patrons
 
 OF SEEING. 
 
 179 
 
 of the contrary opinions should have given 
 instances in support of them that are clear 
 and indisputable ; but I have not found one 
 such instance on either side of the question, 
 in all the authors I have met with. I have 
 given three instances from my own observ- 
 ation, in confirmation of Dr Juriu's opinion, 
 which admit of no doubt ; and one which 
 leans rather to the other opinion, but is 
 dubious. And her3 I must leave the matter 
 to further observation. 
 
 In the 17th section, I have endeavoured to 
 shew that the correspondence and [or] sj'm- 
 patliy of certain points of the two retincB, 
 into which we have resolved all the phceno- 
 mena of single and double vision, is not, as 
 Dr Smith conceived, the effect of custom, 
 nor can [it] be changed by custom, but is a 
 natural and original property of human 
 eyes ; and, in the last section, that it is not 
 owing to an original and natural perception 
 of the true distance of objects from the eye, 
 as Dr Porterfield imagined. After this re- 
 capitulation, which is intended to relieve the 
 attention of the reader, shall we enter into 
 more theories upon this subject ? 
 
 That of Dr Briggs — first published in 
 English, in the " Philosophical Transac- 
 tions," afterwards in Latin, under the title 
 of '' Nova Visionis Theoria," with a prefa- 
 tory epistle of Sir Isaac Newton to the 
 futhor — amounts to this. That the fibres of 
 the optic nerves, passing from correspond- 
 ing points of the retince to the thalami ncr- 
 vorum opticorum, having the same length, 
 the same tension, and a similar situation, 
 will have the same tone ; and, therefore, 
 their vibrations, excited by the impression 
 of the rays of light, will be like unisons in 
 music, and will present one and the same 
 image to the mind : but the fibres passing 
 from parts of the r. lince which do not cor- 
 respond, having (lifi'erent tensions and tones, 
 will have discordant vibrations ; and, there- 
 fore, present different images to the mind. 
 
 I shall not enter upon a particular exam- 
 ination of this theory. It is enough to ob- 
 serve, in general, that it is a system of con- 
 jectures concerning things of whicli we are 
 entirely ignorant ; and that all such theories 
 in philosopliy deserve rather to be laughed 
 at, than to be seriously refuted. 
 
 From the first dawn of philosopliy to this 
 day, it hath been believed that the optic 
 nerves arc intended to carry the images of 
 visible objects from the bottom of the eye to 
 the mind ; and tliat the nerves belonging to 
 the organs of the other senses have a like 
 oflfice.' But how do we know this ? We 
 conjecture it ; and, taking this conjecture 
 for a truth, wo consider how the nerves may 
 best answer this purpose. The system of 
 the nerves, for many ages, was taken to be a 
 
 • Tht> ttntpment i» far too iiii(]iialific(l. — II. 
 
 hydraulic engine, consisting of a bundle of 
 pipes, which carried to andfro a liquorcalled 
 animal spirits. About the time of Dr 
 Briggs, it was thought rather to be a stringed 
 instrument, composed of vibrating chords, 
 each of which had its proper tension and 
 tone. But some, with as great probability, 
 conceived it to be a wind instrument, which 
 played its part by the vibrations of an elastic 
 eether in the nervous fibrUs. 
 
 These, I think, are all the engines into 
 which the nervous system hath been moulded 
 by philosophers, for conveying the images 
 of sensible things from the organ to the 
 sensorlum. And, for all that we know of 
 the matter, every man may freely choose 
 which he thinks fittest for the purpose ; for, 
 from fact and experiment, no one of them 
 can claim preference to another. _ Indeed, 
 they all seem so unhandy engines for carry- 
 ing images, that a man would be tempted to 
 indent a new one. 
 
 Since, therefore, a blind man may guess 
 as well in the dark as one that sees, I beg 
 leave to offer another conjecture touching 
 the nervous system, which, I hope, will 
 answer the purpose as well as those we have 
 mentioned, and which recommends itself by 
 its simplicity. Why may not the optic 
 nerves, for instance, be made up of empty 
 tubes, opening their mouths wide enough to 
 receive the rays of light which form the 
 image upon the retinw, and gently convey- 
 ing them safe, and in their proper order, to 
 the very seat of the soul, until they flash in 
 her face ? It is easy for an ingenious phi. 
 losopher to fit the caliber of these empty 
 tubes to the aiameter of the particles of 
 light, so as they shall receive no grosser 
 kind of matter ; and, if these rays should be 
 in danger of mistaking their way, an expe- 
 dient may also be found to prevent this ; 
 for it requires no more than to bestow u]ion 
 the tubes of the nervous system a peristal- 
 tic motion, like that of the alimentary tube. 
 
 It is a peculiar advantage of this hypo- 
 thesis, that, although all philosophers be- 
 lieve that the species or images of things 
 are conveyed by the nerves to the soul, yet 
 none of their hypotheses shew how this 
 may be done. For how can the images of 
 sound, taste, smell, colour, figure, and all 
 sensible qualities, be made out of the vibra- 
 tions of musical chords, or the undulations 
 of animal s})irits, or of aether ? Wc ought 
 not to suppose means inadequate to tiie 
 end. Is it not as phil(js()[)liical, and more 
 intelligible, to conceive, that, as the stomach 
 receives its food, so the soul receives her 
 images by a kind of nervous deglutition ? 
 I might add, that wc need only continue 
 this iicristaltic motion of the nervous tubes 
 from tlie sniinrinm to tiie extremities of the 
 nerves tiiat servo the muscles, in order to 
 account for nuiscular motion. 
 
 N y
 
 180 
 
 OF THE HUMAN MIND. 
 
 Thus Nature will be consonant to her- 
 self ; and, as sensation will be the convey- 
 ance of the ideal aliment to the mind, so 
 muscular motion will be the expulsion of 
 the recrementitious part of it. For who 
 can deny, that the images of things con- 
 veyed by sensation, may, after due con- 
 coction, become fit to be thrown off by 
 muscular motion ? I only give hints of 
 these things to the ingenious, hoping that in 
 time this hypothesis may be wrought up into 
 a system as truly philosophical as that of ani- 
 mal spirits, or the vibration of nervous fibres. 
 
 To be serious : In the operations of na- 
 ture, I hold the theories of a philosopher, 
 which are unsupported by fact, in the same 
 estimation with the dreams of a man asleep, 
 or the ravings of a madman. We laugh at 
 the Indian philosopher, who, to account 
 for the support of the earth, contrived the 
 hypothesis of a huge elephant, and, to 
 support the elephant, a huge tortoise. 
 If we will candidly confess the truth, we 
 know as little of the operation of the nerves, 
 as he did of the manner in which the earth 
 is supported ; and our hj'potheses about 
 animal spirits, or about the tension and 
 vibrations of the nerves, are as like to be 
 true, as his about the support of the earth. 
 His elephant was a hypothesis, and our 
 hypotheses are elephants. Every theory 
 in philosophy, which is built on pure con- 
 jecture, is an elephant ; and every theory 
 that is supported partly by fact, and partly 
 by conjecture, is like Nebuchadnezzar's 
 image, whose feet were partly of iron and 
 partly of clay. 
 
 The great Newton first gave an example 
 to philosophers, which always ought to be, 
 but rarely hath been followed, by distin- 
 guishing his conjectures from his conclu- 
 sions, and putting the former by themselves, 
 in the modest form of queries. This is fair 
 and legal ; but all other philosophical traf- 
 fic in conjecture ought to be held contra- 
 band and illicit. Indeed, his conjectures 
 have commonly more foundation in fivct, 
 and more verisimilitude, than the dogma- 
 tical theories of most other philosophers ; 
 and, therefore, we ought not to omit that 
 which he hath offered concerning the cause 
 of our seeing objects single with two eyes, 
 in the 15th query annexed to his "Optics." 
 
 " Are not the species of objects seen 
 with both eyes, united where the optic 
 nerves meet before they come into the brain, 
 the fibres on the right side of both nerves 
 uniting there, and after union going thence 
 into the brain in the nerve which is on the 
 right side of the head, and the fibres on the 
 left side of both nerves uniting in the same 
 place, and after union going into the brain 
 in the nerve which is on the left side of the 
 head, and these two nerves meeting in the 
 brain in such a manner that their fibres 
 
 make but one entire species or picture, half 
 of which on the right side of the sensoiiian 
 comes from the right side of both eyea 
 through the right side of both optic nerves, 
 to the place where the nerves meet, and 
 from thence on the right side of the head 
 into the brain, and the other half on the 
 left side of the sensorium comes, in like 
 manner, from the left side of both eyes ? 
 For the optic nerves of such animals as 
 look the same way with both eyes (as men, 
 dogs, sheep, oxen, &c.) meet before they 
 come into the brain ; but the optic nerves 
 of such animals as do not look the same 
 way with both eyes (as of fishes, and of the 
 chameleon) do not meet, if I am rightly in- 
 formed." 
 
 I beg leave to distinguish this query into 
 two, which are of very difi'erent natures ; 
 one being purely anatomical, the other re- 
 lating to the carrying species or pictures of 
 visible objects to the sensorium. 
 
 The first question is, Whether the fibres 
 coming from corresponding points of the 
 two retincB do not unite at the place where 
 the optic nerves meet, and continue united 
 from thence to the brain ; so that the right 
 optic nerve, after the meeting of the two 
 nerves, is composed of the fibres coming 
 from the right side of both retinae, and the 
 left, of the fibres coming from the left side 
 of both relintB .^ 
 
 This is undoubtedly a curious and rational 
 question ; because, if we could find ground 
 from anatomy to answer it in the affirm- 
 ative, it would lead us a step forward in 
 discovering the cause of the correspondence 
 and sympathy which there is between cer- 
 tain points of the two relince. For, although 
 wo know not what is the particular function 
 of the optic nerves, yet it is probable that 
 some impression made upon them, and 
 communicated along their fibres, is neces- 
 sary to vision ; and, whatever be the nature 
 of this impression, if two fibres are united 
 into one, an impression made upon one of 
 them, or upon both, may probably produce 
 the same effect. Anatomists think it a 
 sufficient account of a sympathy between 
 two parts of the body, when they are served 
 by branches of the same nerve ; we should, 
 therefore, look upon it as an important dis- 
 covery in anatomy, if it were found that the 
 same nerve sent branches to the corre- 
 sponding points of the retinw. 
 
 But hath any such discovery been made ? 
 No, not so much as in one subject, as far as 
 I can learn ; but, in several subjects, the 
 contrary seems to have been discovered. 
 Dr Porterfield hath given us two cases at 
 length from Vesalius, and one from Csesal- 
 pmus, wherein the optic nerves, after touch • 
 ing one another as usual, appeared to be 
 refiected back to the same side whence 
 they came, without any mixture of their
 
 OF SEEING. 
 
 1B\ 
 
 fibres. Each of these persons had lost an 
 eye some time before his death, and the 
 optic nerve belonging to that eye was 
 shrunk, so that it could be distinguished 
 from the other at the place where they met. 
 Another case, which the same author gives 
 from Vesalius, is still more remarkable ; 
 for in it the optic nerves did not touch at 
 all ; and yet, upon inquiry, those who were 
 most familiar with the person in his life- 
 time, declared that he never complained of 
 any defect of sight, or of his seeing objects 
 double. Diemerbroeek tells us, that Aqua- 
 pendens [ab Aquapendente] and Valverda 
 likewise affirm, that they have met with 
 subjects wherein the optic nerves did not 
 touch.* 
 
 As these observations were made before 
 Sir Isaac Newton put this query, it is un- 
 certain whether he was ignorant of them, 
 or whether he suspected some inaccu- 
 racy in them, and desired that the matter 
 might be more carefully examined. But, 
 from the following passage of the most 
 accurate Winslow, it does not appear that 
 later observations have been more favour- 
 able to his conjecture. " The union of 
 tliese (optic) nerves, by the small curva- 
 tures of their corjiJia, is very difficult to be 
 unfolded in human bodies. This union is 
 commonly found to be very close ; but, in 
 some subjects, it seems to be no more than 
 a strong adhesion — in others, to be partly 
 made by an intersection or crossing of hbres. 
 They have been found quite sejiarate ; and, 
 in other subjects, one of them has been 
 found to be very much altered both in size 
 and colour through its whole passage, the 
 other remaining in its natural state." 
 
 When we consider this conjecture of Sir 
 Isaac Newton by itself, it appears more 
 ingenious, and to have more verisimilitude, 
 than anything that has been ofl'ered upon 
 the suViject ; and we admire the caution 
 and modesty of tlie author, in i)roposing it 
 only as a subject of inquiry : but when we 
 compare it with the observations of anato- 
 mists which contradict it,i- we are naturally 
 
 ♦ See Meckel's " Pathologische Anatomie," 1., p. 
 3<J'J.— H. 
 
 -f Ana'nniifts are now nearly agreed, tliat, in the 
 normal state, there is a partial dccu^fatioii of the 
 human optio nerve. Soemmering, 'I reviraniis, lUi- 
 dolphi, Johannes Mueller, I.anpenbcck, MaKeiidi'.', 
 Mayo, SiC, are paramount au'liority for the fact. 1 
 d<^ni<t know whtlher tlic oli»trva' on h.is been made, 
 that the decree of di cu-sat on in ditftrcnt animals is 
 exactly in tlie nvcrse ratio of what wc mifiht have 
 been led, aljii st sight, theoretically to anticipate. In 
 propor'ion as the mnvetKPnce i~ complete — i'. c, 
 where the axis of the held of vision of the severafeyes 
 coincides wi!h the axis of the fii Id of visf n common 
 to hotli, as in men and apes — there we find the de- 
 cussation most partial and obscure; whereas, in the 
 lower animals, in r>roportion as* we-find the fields of 
 the t wo eyci exclusive ofeach oilier, and whei e, conse- 
 quently, the necehsity of bringing thc' twoorjjans into 
 union miKht seem ahohshcd, there, however, we find 
 the crossing of the optic filjies comiilete. In fishes, 
 accordingly, it it distinct and isolated; in birds, it taker 
 
 led to this reflection, That, if we trust to 
 the conjectures of men of the greatest 
 genius in the operations of nature, we have 
 only the chance of going wrong in an inge- 
 nious manner. 
 
 The second part of the query is, Whether 
 the two species of objects from the two eyes 
 are not, at the place where the optic nerves 
 meet, united into one species or picture, 
 half of which is carried thence to the sen. 
 solium in the right optic nerve, and the 
 other half in the left ? and whether these 
 two halves are not so put together again at 
 the se7isorium, as to make one species or 
 picture ? 
 
 Here it seems natural to put the previous 
 question. What reason have we to believe 
 that pictures of objects are at all carried to 
 the sensoihim, either by the optic nerves, 
 or by any other nerves ? Is it not possible 
 that this great philosopher, as well as many 
 of a lower form, having been led into this 
 opinion at first by education, may have con- 
 tinued in it, because he never thought of 
 calling it in question .-' I confess this was 
 my own case for a considerable part of my 
 life. But since I was led by accident to 
 think seriously what reason I had to believe 
 it, I could find none at all. It seems to be 
 a mere hypothesis, as much as the Indian 
 philosopher's elephant. I am not conscious 
 of any pictures of external objects in my 
 sensur'mm, any more than in my stomach : 
 the things which I perceive by my senses, 
 appear to be external, and not in any part 
 of the brain ; and my sensations, properly 
 so called, have no resemblance of external 
 objects. 
 
 The conclusion from all that hath been 
 said, in no less than seven sections, upon 
 our seeing objects single with two eyes, 
 is this — That, by an original property 
 of human eyes, objects painted upon the 
 centres of the two retiiiai, or upon jioints 
 siniihirly situate with regard to the centres, 
 appear in the same visible place ; that the 
 most plausible attempts to account for this 
 property of the eyes, have been unsuccess- 
 ful ; and, therefore, that it must be either 
 a primary law of our constitution, or the 
 consecjuence of some more general law, 
 which is not yet discovered. 
 
 We have now finished what we intended 
 to say, both of the visible ap]iearaiices of 
 things to the eye, and of the laws of our 
 constitution by which those appearances 
 
 m re the appearance of .in interl.iccmcnt ; in the 
 niatnmalia, that of a fusion of snbs'atice. A second 
 coiisideratn n, however, riconclestlieory and observ. 
 a'ion. Some, however, as Woolaston, mnko the 
 paralU I motion of the eyes to be dependent on the 
 connection of the opti(' neivcs ; and, brsides expiri. 
 nients, there .ire varii us patliolo(;ieal ca-is in (avoui 
 of (Manendie's opinion, that the yi/Z/i pair are Ihi 
 nerves on wliicli the cncrnieH of ti(0'l, liiariiiK 
 tin<//,am\'lii!.le an- proxinmtely and priiKii);dly dp. 
 peniltnl — H.
 
 182 
 
 OF THE HUMAN MIND. 
 
 are exhibited. But it was observed, in the 
 bcgimiiDg of this chapter, that the visible 
 appearances of objects serve only as signs 
 of their distance, magnitude, figure, and 
 other tangible quahties. The visible ap- 
 pearance is that which is presented to the 
 mind by nature, according to those laws of 
 our constitution which have been explained. 
 But the thing signified by that appearance, 
 is that which is presented to the mind by 
 custom. 
 
 When one speaks to us in a language 
 that is familiar, we hear certain sounds, 
 and this is all the effect that his discourse 
 has upon us by nature ; but by custom we 
 understand the meaning of these sounds ; 
 and, therefore, we fix our attention, not 
 upon the sounds, but upon the thmgs sig- 
 nified by them. In like manner, we see 
 only the visible appearance of objects by 
 nature ; but we learn by custom to inter- 
 pret these appearances, and to understand 
 their meaning. And when this visual 
 language is learned, and becomes familiar, 
 we attend only to the things signified ; and 
 cannot, without great difficulty, attend to 
 the signs by which they are presented. The 
 mind passes from one to the other so 
 rapidly and so familiarly, that no trace of 
 the sign is left in the memory, and we seem 
 immediately, and without the intervention 
 of any sign, to perceive the thing sig- 
 nified. 
 
 When I look at the apple-tree which 
 stands before my window, I perceive, at the 
 first glance, its distance and magnitude, the 
 roughness of its trunk, the disposition of 
 its branches, the figure of its leaves and 
 fruit. I seem to perceive all these things 
 immediately. The visible appearance which 
 presented them all to the mind, has entirely 
 escaped me ; I cannot, without great diffi- 
 culty, and painful abstraction, attend to it, 
 even when it stands before me. Yet it is 
 certain that this visible appearance only 
 is presented to my eye by nature, and that 
 I learned by custom to collect all the rest 
 from it. If I had never seen before now, 
 I should not perceive either the distance or 
 tangible figure of the tree ; and it would 
 have required the practice of seeing for 
 many months, to change that original per- 
 ception which nature gave me by my eyes, 
 into that which I now have by custom. 
 
 The objects which we see naturally and 
 originally, as hath been before observed, 
 have length and breadth, but no thickness 
 nor distance from the eye. Custom, by a 
 kind of legerdemain, withdraws gradually 
 these original and proper objects of sight, 
 and substitutes in their place objects of 
 touch, which have length, breadth, and 
 thickness, and a determinate distance from 
 the eye. By what means this change is 
 brought about, and what principles of the 
 
 human mind concur in it, we are next to 
 inquire. 
 
 Section XX. 
 
 OF PERCEPTION IN GENERAL. 
 
 Sensation, and the perception-]- of exter- 
 nal objects by the senses, though very dif- 
 ferent in their nature, have commonly been 
 considered as one and the same thing.* 
 The purposes of common life do not make 
 it necessary to distinguish them, and the 
 received opinions of philosophers tend ra- 
 ther to confound them ; but, without at- 
 tending carefully to this distinction, it is 
 impossible to have any just conception of 
 the operations of our senses. .The most 
 shnple operations of the mind, admit not of 
 a logical definition : all we can do is to de- 
 scribe them, so as to lead those who are 
 conscious of them in themselves, to attend 
 to them, and reflect upon them ; and it is 
 often very difficult to describe them so as to 
 answer this intention. 
 
 The same mode of expression is used to 
 denote sensation and perception ; and, there- 
 fore, we are apt to look upon them as things 
 of the same nature. Thus, / feel a pain ; 
 I see a tree : the first denoteth a sensation, 
 the last a perception. The grammatical 
 analysis of both expressions is the same : 
 
 • Nothing in the compass of inductive reasoning 
 appears more satisfactory than Berkeley's demon- 
 stration of the necessity and manner of our learn- 
 ing, by a slow process of observation and comparison 
 alone, the connection between the perceptions of 
 vision and touch, and, in general, all that relates to 
 the distance and real m.ignitud > of external things. 
 But, although the same necessity seems in theory 
 equally incumbent on the lower aiiim.ils as on man, 
 yet this theory is provokingly — and that by the most 
 manifest experience — found totally at fault with re- 
 gard to them ; for we find that all the animals who 
 possess at birth the power of regulated motion (and 
 these are those only through whom the truth ot the 
 theory can be brought to the test of a decisive ex. 
 periment) possess also from birth the whole appre- 
 hension of distance, &c , which they are ever known 
 to exhibit. The solution of this difference, by a 
 resort to instinct, ;s unsatisfactory ; for instinct is, 
 in fact, an occult principle— a kind of natural revi 1- 
 ation — and the hypothesisof instinct, therefore, only 
 a confession of our ignorance : and, at the same time, 
 if instinct be allowed in the lower animals, how 
 can we determine whether and how far instinct 
 may not in like manner operate to the same reyult 
 in man ?— I have discovered, and, by a wide induc- 
 tion, estatlished, that the power ot regulated mo. 
 lion at birth is, in all animals, governed by the de- 
 veloperaent, at that period, of the cerebellum, in pro- 
 portion to the brain proper. Is this law to be exte ded 
 to the faculty of determining distances, &c., by sight? 
 — H. 
 
 t On the distinction of Sensation proper, from 
 Perception proper, see " Kssays on the Intellectual 
 I'owers," Essay II., chap. Hi, and Note D.* Kcid 
 himself, especially in this work, has not been always 
 rigid in observing their discrimination. — H. 
 
 X Not only are they difTerent, but — what has escaped 
 our philosiphers — the law ot their manifestation 
 is, that, while bitli are co-existent, e.ich is always in 
 the inverse ratio of tne other. Percepiiiin is the-objcr- 
 tive. Sensation the sufjjectivo, element. J'his by I he 
 way. — H.
 
 OF SEEING. 
 
 183 
 
 for both consist of an active verb and an 
 object. But, if we attend to the things sig- 
 nified by these expressions, we shall find 
 that, in the first, the distinction between the 
 act and tlie object is not real but gramma- 
 tical ; in the second, the distinction is not 
 only grammatical but real. 
 
 The form of the expression, I feel pain, 
 might seem to imply that the feeling is 
 something distinct from the pain felt ; yet, 
 in reality, there is no distinction. As 
 thinking a thought is an expression which 
 could signify no more than thinking, so 
 feeling a pain signifies no more than being 
 pained. What we have said of pain is ap- 
 licable to every other mere sensation. It 
 is difficult to give instances, very few of 
 our sensations having names ; and, where 
 they have, the name being common to the 
 sensation, and to something else which is 
 associated with it. But, when we attend 
 to the sensation by itself, and separate it 
 from other things which are conjoined 
 with it in the imagination, it appears to 
 be something which can have no existence 
 but in a sentient mind, no distinction 
 from the act of the mind bv which it is 
 felt. 
 
 Perception, as we here understand it, 
 hath always an object distinct from the act 
 by which it is perceived; an object which 
 may exist whether it be perceived or not. 
 I perceive a tree that grows before my win- 
 dow ; there is here an object which is per- 
 ceived, and an act of the mind by which it 
 is perceived ; and these two are not only 
 distinguishable, but they are extremely un- 
 like in their natures- The object is made 
 up of a trunk, branches, and leaves ; but 
 the act of the mind by which it is per- 
 ceived hath neither trunk, branches, nor 
 leaves. I am conscious of this act of my 
 mind, and I can reflect upon it ; but it is 
 too simple to admit of an analysis, and I 
 cannot find proper words to describe it. I 
 find nothing that resembles it so much as 
 the remembrance of the tree, or the ima- 
 gination of it. Yet both these differ essen- 
 tially from perception ; they difi'er likewise 
 one from another. It is in vain that a 
 philosopher assures me, that the imagina- 
 tion of the tree, the remembrance of it, and 
 the perception of it, are all one, and dill'er 
 only in degree of vivacity. I know the 
 contrary ; for I am as well acquainted witii 
 all the three as I am with the apartments 
 of my own house. I know this also, that 
 the perception of an object implies both a 
 concei)tion of its form, and a belief of its 
 present existence.* I know, moreover, that 
 
 ♦ It 19 to be observed Ihat Reid himself does not 
 dinrrimiiia o perception ami iinaninnliun by any 
 e»>eiilial (bfTircncc. Afcoriiint; to liiin, percfi/tidii 
 ii only tbc conception (imagination) of an object, ac- 
 rom)>.ioi<'il with a bcbel of its iiri'unt existence; and 
 even Ibis lusi distinction, a mere " laith witboiii 
 
 this belief is not the effect of argumentation 
 and reasoning ; it is the immediate eft'ect of 
 my constitution. 
 
 I am aware that this belief which I have 
 in perception stands exposed to the strongest 
 batteries of scepticism. But they make no 
 great impression upon it. The sceptic asks 
 me. Why do you believe the existence of 
 the external object which you perceive ? 
 This belief, sir, is none of my manufacture ; 
 it came from the mint of Nature ; it bears 
 her image and superscription ; and, if it is 
 not right, the fault is not mine : I even took 
 it upon trust, and without suspicion. Rea- 
 son, says the sceptic, is the only judge of 
 trutli, and you ought to throw ofi' every opi- 
 nion and every belief that is not grounded 
 on reason. Why, sir, should I believe the 
 faculty of reason more than that of percep- 
 tion ? — they came both out of the same shop, 
 and were made by the same artist ; and if 
 he puts one piece of false ware into ray 
 hands, what should hinder him from put- 
 ting another ?* 
 
 Perhaps the sceptic will agree to distrust 
 reason, rather than give any credit to per- 
 ception. For, says he, since, by your own 
 concession, the object which you perceive, 
 and that act of your mind by which you 
 perceive it, are quite different things, the 
 one may exist without the other ; and, as 
 the object may exist without being per- 
 ceived, so the perception may exist without 
 an object. There is nothing so shameful 
 in a philosopher as to be deceived and de- 
 luded ; and, therefore, you ought to resolve 
 firmly to withhold assent, and to throw off 
 this belief of external objects, which may be 
 all delusion. For my part, I will never 
 attempt to throw it off; and, although the 
 sober part of mankind will not be very 
 anxious to know my reasons, yet, if they 
 can be of use to any sceptic, they are 
 these : — 
 
 First, because it is not in my power : why, 
 then, should I make a vain attempt ? It 
 would be agreeable to fly to the moon, and 
 to make a visit to Jupiter and Saturn; but, 
 when I know that Natin-e has bound me 
 down by the law of gravitation to this planet 
 which I inhabit, I rest contented, and quietly 
 
 knowledge," is surrendered by Mr Stewart. Now, 
 as conception (imagination) is only immediately cog- 
 nisant of the cijo, so must pcrcp' ion on Ibis doctrine 
 be a knowledge purely .v"'yr///'('. I'ercipiion niUMt 
 be wholly diflerent in kiiul Irom ('onception, if we are 
 to possess a faculty inlornung us of the existence and 
 qualities of an external world; and, unless wc are 
 possessed of such a faculty, we .-ball never be compe. 
 lent to vindicate more than an ideal reality lo the 
 objects of our cognitions, — II. 
 
 ■ This argument would bo pood in favour of our 
 belief, that we are really percipient of a tiott.epo : 
 it is not good in favour of (air belief that a tion.i-po 
 really exists, our perception of its rel exiKtcnee 
 being abiiidoned. Mankind liave the latter belief 
 only as they h.ive the former ; and, if we .iri' deceived 
 by our Nature touching the one, it is al'Minl to up 
 peal lo her veracity in proof ol the iitlier — II.
 
 184 
 
 OF THE HUMAN MIND. 
 
 suffer myself to be carried along in its orbit. 
 My belief is carried along by perception, as 
 irresistibly as my body by the earth. And 
 the greatest sceptic will find himself to be 
 in the same condition. He may struggle 
 hard to disbelieve the informations of his 
 senses, as a man does to swim against a tor- 
 rent ; but, ah ! it is in vain. It is in vain 
 that he strains every nerve, and wrestles 
 with nature, and with every object that 
 strikes upon his senses. For, after all, 
 when his strength is spent in the fruitless 
 attempt, he will be carried down the tor- 
 rent with the common herd of believers. 
 
 Secondly, I think it would not be pru- 
 dent to throvv' off this belief, if it were in 
 my power. If Nature intended to deceive 
 me, and impose upon me by false appear- 
 ances, and I, by my great cunning and pro- 
 found logic, have discovered the imposture, 
 prudence would dictate to me, in this case, 
 even to put up [with] this indignity done 
 me, as quietly as I could, and not to call 
 her an impostor to her face, lest she should 
 be even with me in another way. For 
 what do I gain by resenting this injury ? 
 You ought at least not to believe what she 
 says. This indeed seems reasonable, if 
 she intends to inajjose upon me. But what 
 is the consequence ? 1 resolve not to be- 
 lieve my senses. I break my nose against 
 a post that comes in my way ; I step into 
 a dirty keunel ; and, after twenty such 
 wise and rational actions, I am taken up 
 and clapped into a mad-house. Now, I con- 
 fess I would rather make one of the credu- 
 lous fools whom Nature imposes upon, than 
 of those wise and rational philosophers 
 who resolve to withhold assent at all tliis 
 expense. If a man pretends to be a scep- 
 tic with regard to the informations of 
 sense, and yet prudently keeps out of harm's 
 way as other men do, he must excuse my 
 suspicion, that he either acts the hypocrite, 
 or imposes upon himself. For, if the scale 
 of his belief were so evenly poised as to 
 lean no more to one side than to the con- 
 trary, it is impossible that his actions could be 
 directed by any rules of common prudence.* 
 
 Thirdly, Although the two reasons al- 
 ready mentioned are perhaps two more than 
 enough, I shall offer a third. I gave im- 
 plicit belief to the informations of Nature 
 by my senses, for a considerable part of my 
 life, before I had learned so much logic as 
 to be able to start a doubt concerning them. 
 And now, when I reflect upon what is past, 
 I do not find that I have been imposed upon 
 by this belief. I find that without it I must 
 have perished by a thousand accidents. I 
 find that without it I should have been no 
 wiser now than wlien I was born. I should 
 
 • This is not a fair consequence of Idealism ; there. 
 fftc, it is not a reduclw ad absjadum. — H. 
 
 not even have been able to acquire that 
 logic which suggests these sceptical doubts 
 with regard to my senses. Therefore, I 
 consider this instinctive belief as one of the 
 best gifts of Nature. I thank the Author of 
 my being, who bestowed it upon nie before 
 the eyes of my reason were opened, and 
 still bestows it upon me, to be my guide 
 where reason leaves me in the dark. And 
 now I yield to the direction of my senses, 
 not from instinct only, but from confidence 
 and trust in a faithful and beneficent Moni- 
 tor, grounded upon the experience of his 
 paternal care and goodness. 
 
 In all this, I deal with the Author of my 
 being, no otherwise than I thought it reason- 
 able to deal with my parents and tutors. I 
 believed by instinct whatever they told me, 
 long before I had the idea of a lie, or thought 
 of the possibility of their deceiving me. 
 Afterwards, upon reflection, I found they 
 liad acted like fair and honest people, who 
 wished me well. I found that, if I had not 
 believed what they told me, before I could 
 give a reason of my belief, I had to this day 
 been little better than a changeling. And 
 although tliis natural credulity hath some- 
 times occasioned my being imposed upon 
 by deceivers, yet it hath been of infinite 
 advantage to me upon the whole ; therefore, 
 I consider it as another good gift of Nature. 
 And I contmue to give that credit, from 
 reflection, to those of whose integrity and 
 veracity I have had experience, which be- 
 fore I gave from instinct. 
 
 There is a much greater similitude than 
 is commonly imagined, between the testi- 
 mony of nature given by our senses, and 
 the testimony of men given by language. 
 The credit we give to both is at first the 
 effect of instinct* only. When we grow 
 up, and begin to reason about them, the 
 credit given to human testimony is re- 
 strained and weakened, by the experience 
 we have of deceit. But the credit given to 
 the testimony of our senses, is established 
 and confirmed by the uniformity and con- 
 stancy of the laws of nature. 
 
 Our perceptions are of two kinds : some 
 are natural and original ; others acquired, 
 and the fruit of experience. When I per- 
 ceive that this is the taste of cyder, that of 
 brandy ; that this is the smell of an apple, 
 that of an orange ; that this is the noise of 
 thunder, that the ringing of bells ; this the 
 sound of a coach passing, that the voice of 
 such a friend : these perceptions, and others 
 of the same kind, are not original — ihey are 
 acquired. But the perception which I have, 
 by touch, of the hardness and softness of 
 bodies, of their extension, figure, and mo- 
 tion, is not acquired — it is original. 
 
 * On the proprielv ol the term " instinct," tie in 
 Note A— H.
 
 OF SEEING. 
 
 185 
 
 lu all our senses, the aei|uired percep- 
 tions are many more than the original, 
 especially in sight. By this sense we per- 
 ceive originally the visible figure and colour 
 of bodies only, and their visible place :* 
 but we learn to perceive by tlie eye, almost 
 everything which we can perceive by 
 touch. The original perceptions of this 
 sense serve only as signs to introduce the 
 acquired. 
 
 The signs by which objects are presented 
 to us in perception, are the language of 
 Nature to man ; and as, in many respects, 
 if hath great affinity with the language of 
 man to man, so particularly in this, that 
 both are partly natural and original, partly 
 acquired by custom. Our original or 
 natural perceptions are analogous to the 
 natural language of man to man, of which 
 we took notice in the fourth chapter ; and 
 our acquired perceptions are analogous to 
 artificial language, which, in our mother- 
 tongue, is got very much in the same man- 
 ner with our acquired perceptions — as we 
 shall afterwards more fully explain. 
 
 Not only men, but children, idiots, and 
 brutes, acquire by habit many perceptions 
 which they had not originally. Almost 
 every employment in life hath perct'ptioijs 
 of this kind" that are peculiar to it. The 
 shepherd knows every sheep of his flock, as 
 we do our acquaintance, and can pick them 
 out of another fiock one by one. The 
 butcher knows by sight the weight and 
 quality of his beeves and sheep before they 
 are killed. The farmer perceives by his 
 eye, very nearly, the quantity of hay in a 
 rick, or of corn in a heap. The sailor sees 
 the burtlien, the built, and the distance of 
 a ship at sea, while she is a great way off. 
 Every man accustomed to writing, distin- 
 guishes his acquaintance by their hand- 
 writing, as he does by their faces. And 
 the painter distinguishes, in the w^rks of his 
 art, the style of all the great masters. In 
 a word, acquired perception is very different 
 in different persons, aci-ording to the divers- 
 ity of objects about which they are em- 
 ployed, and the application they bestow in 
 observing them. 
 
 Perception ounht not only to be distin- 
 guished from sensntion, but likewise from 
 that knowledge of the objects of sense 
 which is got by reasoning. There is no 
 reasoning in perception, as hath been ob- 
 served. The belief which is implied in it, 
 is tile effect of instinct. But there are 
 many tilings, with regard to sensible ob- 
 jects, wliicli we can irifcsr from what we 
 perceive ; and such conclusions of reason 
 ougjit to be distinguished from what is 
 merely perceived. When I look at tiie 
 
 • In thin palliate Keid atiinitu KiKurc and Place 
 (rotup^iueiitly, rCxtcimion) to be on'ghinl p' rccptiotis 
 ol vlainn. Sec al)Ovc, \>. \i'A, 1> . noie \. — II. 
 
 moon, I perceive her to be soinetmies cir- 
 cular, sometimes horned, and sometimes 
 gibbous. This is simple perception, and is 
 the same in the philosopher and in the 
 clown : but from these various appearances 
 of her enlightened part, I infer that she is 
 really of a spherical figure. This conclu- 
 sion is not obtained by simple perception, 
 but by reasoning. Simple jierception has 
 the same relation to the conclusions of rea- 
 son drawn from our perceptions, as the 
 axioms in mathematics have to the pro- 
 positions. I cannot demonstrate that two 
 quantities which are equal to the same 
 quantity, are equal to each other ; neither 
 can I demonstrate that the tree which 
 I perceive, exists. But, by the constitution 
 of my nature, my belief is irresistibly car- 
 ried along by my apprehension of the 
 axiom ; and, by the constitution of my 
 nature, my belief is no less irresistilily car- 
 ried along by my perception of the tree. 
 All reasoning is from principles. The first 
 principles of mathematical reasoning are 
 mathematical axioms and definitions ; and 
 the first principles of all our reasoning 
 about existences, are our perceptions. The 
 first principles of every kind of reasoning 
 are given us by Nature, and are of equal 
 authority with the faculty of reason itself, 
 which is also the gift of Nature. The con- 
 clusions of reason are all built upon first 
 principles, and can have no other founda- 
 tion. INIost justly, therefore, do such prin- 
 ciples disdain to be tr'ed by reason, and 
 laugh at all the artillery of the logician, 
 when it is directed against them. 
 
 When a long train of reasoning is neces- 
 sary in demonstrating a mathematical pro- 
 position, it is easily distinguished from an 
 axiom ; and they seem to be things of a very 
 different nature. But there are some pro- 
 positions which lie so near to axioms, that 
 it is difficult to say whether they ought to 
 be held as axioms, or demonstrated as pro- 
 positions. The same thing holds with 
 regard to perception, and the conclusions 
 drawn from it. Some of these conclusions 
 follow our perceptions so easily, and are so 
 immediately connected with them, that it 
 is difficult to fix the limit which divides the 
 one from the other. 
 
 Perception, whether original or acquired, 
 implies no exercise of reason ; and is com- 
 mon to men, children, idiots, and brutes. 
 The more obvious conclusions drawn from 
 our |)erc('ptions, by reason, make wljat wo 
 call conanim un<li rslaiKliiig ; l)y which men 
 coniluct themselves in the comiiKni all'airs 
 of life, and liy which they are distinguished 
 from idiots. The more remote conclusions 
 wiiich are drawn from our p<!rcej)tioii8, by 
 reason, make wliat we commonly call ^clftue 
 in tli(t v;irious ]>arts nf ti.itiin-, wlicllicr in 
 agriculture, mediciiK', nicciiiiiiicH, (u- in any
 
 186 
 
 OF THE HUMAN MIND. 
 
 part of natural pliilosopliy. When I see a 
 garden in good order, containing a great 
 variety of things of the best kinds, and in 
 the most flourishing condition, I immedi- 
 ately conclude from these signs the skill 
 and industry of the gardener. A farmer, 
 when he rises in the morning, and perceives 
 that the neighbouring brook overflows his 
 field, concludes that a great deal of rain 
 hath fallen in the night. Perceiving his 
 fence broken, and his corn trodden down, 
 he concludes that some of his own or his 
 neighbours' cattle have broke loose. Per- 
 ceiving that his stable-door is broke open, 
 and some of his horses gone, he concludes 
 tliat a thief has carried them off. He traces 
 the prints of his horses' feet in the soft 
 ground, and by them discovers which road 
 the thief hath taken. These are instances 
 of common understanding, which dwells so 
 near to perception that it is difficult to trace 
 the line which divides the one from the other. 
 In like manner, the science of nature dwells 
 so near to common understanding that we 
 cannot discern where the latter ends and the 
 former begins. I perceive that bodies lighter 
 than water swim in water, and that those 
 which are heavier sink. Hence I conclude, 
 that, if a body remains wherever it is put 
 under water, whether at the top or bottom, 
 it is precisely of the same weight with water. 
 If it will rest only when part of it is above 
 water, it is lighter than water. And the 
 greater the part above water is, compared 
 with the whole, the lighter is the body. If 
 it had no gravity at all, it would make no 
 impression upon the water, but stand wholly 
 above it. Thus, every man, by common 
 understanding, has a rule by which he 
 judges of the specific gravity of bodies 
 which swim in water : and a step or two 
 more leads him into the science of hydro- 
 statics. 
 
 All that we know of nature, or of exist- 
 ences, may be compared to a tree, which 
 hath its root, trunk, and branches. In this 
 tree of knowledge, perception is the root, 
 common imderstanding is the trunk, and 
 the sciences are the branches. 
 
 Section XXI. 
 
 OF THE PROCESS OF NATURE IN PERCEPTION. 
 
 Although there is no reasoning in per- 
 ception, yet there are certain means and 
 instruments, which, by the appointment of 
 nature, must intervene between the object 
 and our perception of it ; and, by these, 
 our perceptions are limited and regulated. 
 First, If the object is not in contact with 
 the organ of sense, there must be some 
 medium which passes between them. Thus, 
 in vision, the rays of light ; in hearing, the 
 
 vibrations of elastic air ; in smelling, the 
 efiluvia of the bodysmelled — must pass from 
 the object to the organ ; otherwise we have 
 no perception.* Secondly, There must be 
 some action or impression upon the organ 
 of sense, either by the immediate applica- 
 tion of the object, or by the medium that 
 goes between them. Thirdly, The nerves 
 which go from the brain to the organ must 
 receive some impression by means of that 
 which was made upon the organ ; and, pro- 
 bably, by means of the nerves, some im- 
 pression must be made upon the brain. 
 Fourthly, The impression made upon the 
 organ, nerves, and brain, is followed by a 
 sensation. And, last of all, This sensation 
 is followed by the perception of the object. -j- 
 
 Thus, our perception of objects is the re- 
 sult of a train of operations ; some of which 
 affect the body only, others affect the mind. 
 We know very little of the nature of some 
 of these operations ; we know not at all how 
 they are connected together, or in what way 
 they contribute to that perception which is 
 the result of the whole ; but, by the laws of 
 our constitution, we perceive objects in this, 
 and in no other way. 
 
 There may be other beings who can per- 
 ceive external objects without rays of light, 
 
 or vibrations of air, or effluvia of bodies 
 
 without impressions on bodily organs, or 
 even without sensations ; but we are so 
 framed by the Author of Nature, that, even 
 when we are surrounded by external objects, 
 we may perceive none of them. Our faculty 
 of perceiving an object lies dormant, until 
 it is roused and stimulated by a certain 
 corresponding sensation. Nor is this sens- 
 ation always at hand to perform its office ; 
 for it enters into the mind only in conse- 
 quence of a certain corresponding impres- 
 sion made on the organ of sense by the ob- 
 ject. 
 
 Let us trace this correspondence of im- 
 pressions, sensations, and perceptions, as 
 far as we can — beginning with that which 
 is first in order, the impression made upon 
 the bodily organ. But, alas ! we know not 
 of what nature these impressions are, far 
 less how they excite sensations in the mind. 
 
 We know that one body may act upon 
 another by pressure, by percussion, by at- 
 traction, by repulsion, and, probably, in 
 many other ways which we neither know 
 nor have names to express. But in which 
 of these ways objects, when perceived by 
 us, act upon the organs of sense, these 
 organs upon the nerves, and the nerves 
 
 * The only object ol perception is the immediate 
 object. J he distant reality — he mediate object, ot 
 object simply of Reid and other p' ilo=opbers— isun. 
 known to the perception ot sense, and only reached 
 by reasoning. — H. 
 
 f I'hat sensation prop r precedes percept on pro- 
 per is a false assumption. They are simultaneous 
 elements of the same indivisible energy. — H.
 
 OF SEEING. 
 
 187 
 
 upon the brain, we know not. Can any 
 man tell me how, in vision, the rays of light 
 act upon the retina, how the retina acts 
 upon the optic nerve, and how the optic 
 nerve acts upon the brain ? No man can. 
 When I feel the pain of the gout in my 
 toe, I know that there is some unusual im- 
 pression made upon that part of my body. 
 But of what kind is it ? Are the small 
 vessels distended with some redundant 
 elastic, or unelastic fluid? Are the fibres 
 unusually stretched ? Are they torn 
 asunder by force, or gnawed and corroded 
 by some acrid humour ? I can answer 
 none of these questions. All that I feel is 
 pain, which is not an impression upon the 
 body, but upon the mind ; and all that I 
 perceive by this sensation is, that some dis- 
 temper in my toe occasions this pain. But, 
 as 1 know not the natural temper and tex- 
 ture of my toe when it is at ease, I know as 
 little what cliange or disorder of its parts 
 occasions this uneasy sensation. In like 
 manner, in every other sensation, there is, 
 without doubt, some impression made upon 
 the organ of sense ; but an impreasion of 
 which we know not the nature. It is too 
 subtile to be discovered by our senses, and 
 we may make a thousand conjectures with- 
 out coming near the truth. If we under- 
 stood the structure of our organs of sense 
 so minutely as to discover what eS'ects are 
 produced upon them by external objects, 
 this knowledge would contribute nothing to 
 our perception of the object ; for they per- 
 ceive as distinctly who know least about the 
 manner of perception, as the greatest adepts. 
 1 1 is necessary that the impression be made 
 upon our organs, but not that it be known. 
 Nature carries on this part of the process 
 of perception, without our consciousness or 
 concurrence. 
 
 But we cannot be unconscious of the next 
 step in this process — the sensation of the 
 mind, which always immediately follows the 
 impression made upon the body. It is 
 essential to a sensation to be felt, and it can 
 be nothing more than we feel it to be. If 
 we can only acquire the habit of attending 
 to our sensations, we may know them per- 
 fectly. But how are the (sensations of the 
 mind produced by impressions upon the 
 body ? Of this we are absolutely ignorant, 
 having no means of knowing how the body 
 acts upon the mind, or the mind upon the 
 body. When we consider tlie nature and 
 attributes of both, they seem to be so difl'or- 
 ent, and so unlike, that we can find no jiandlo 
 by which the one may lay hrjlii of the otlier. 
 There is a deep and a dark gulf between 
 them, which our understanding cannot j)as.s ; 
 and the manner of their corrcsjiondence and 
 intercourse is absolutely unknown. 
 
 Kxpcrience ttachcH us, tluit certain iin- 
 prcHsions upou the body arc constantly fol- 
 
 lowed by certain sensations of the mind ; 
 and that, on the other hand, certain deter- 
 minations of the mind are constantly fol- 
 lowed by certain motions in the body ; but 
 we see not the chain that ties these things 
 together. Who knows but their connection 
 may be arbitrary, and owing to the will of 
 our Maker ? Perhaps the same sensations 
 might have been connected with other im- 
 pressions, or other bodily organs. Perhaps 
 we might have been so made as to taste with 
 our fingers, to smell with our ears, and to 
 hear by the nose. Perhaps we might have 
 been so made as to have all the sensations 
 and perceptions which we have, without any 
 impression made upon our bodily organs at 
 all. 
 
 However these things may be, if Nature 
 had given us nothing more than impressions 
 made upon the body, and sensations in our 
 minds corresponding to them, we should, in 
 that case, have been merely sentient, but not 
 percipient beings. We sliould never have 
 been able to form a conception of any ex- 
 ternal object, far less a belief of its exist- 
 ence. Our sensations have no resemblance 
 to external objects ; nor can we discover, 
 by our reason, any necessary connection 
 between the existence of the former, and 
 that of the latter. 
 
 We might, perhaps, have been made of 
 such a constitution as to have our present 
 perceptions connected with other sensations. 
 We might, perhaps, have had the percep- 
 tion of external objects, without either im- 
 pressions upon the organs of sense, or sens- 
 ations. Or, lastly. The perceptions we have, 
 might have been immediately connected 
 with the impressions ujion our organs, with- 
 out any intervention of sensations. This 
 last seems really to be the case in one in- 
 stance — to wit, in our perception of the 
 visible figure of bodies, as was observed in 
 the eighth section of this chapter. 
 
 The process of Nature, in perception by 
 the senses, may, therefore, be conceived as a 
 kind of drama, wherein some things are per- 
 formed behind the scenes, others are repre- 
 sented to the mind in ditt'erent scenes, oiie 
 succeeding anotlier. The impression made 
 by tlie object upon the organ, either by im- 
 mediate contact or by some intervening 
 medium, as well as the impression made 
 upon the nerves and brain, is performed 
 beiiindthe scenes, and the mind sees nothing 
 of it. But every such impression, by the 
 laws of the drama, is followed liy a sensa- 
 tion, whicli is the first scene eNliil'ited to 
 the mind ; and this scene is quickly suc- 
 ceeded* by another, which is the percep- 
 tion of tlic oliject. 
 
 In this drama. Nature is the actor, we 
 are the spectators. We know notliing of 
 
 • See the prcroding note— H.
 
 188 
 
 OF THE HUMAN MIND. 
 
 the machinery by means of which every 
 different impression upon the organ, nerves, 
 and brain, exhibits its corresponding sens- 
 ation ; or of the machinery by means of 
 which each sensation exhibits its corre- 
 sponding perception. We are inspired with 
 the sensation, and we are inspired with the 
 corresponding perception, by means un- 
 known.* And, because the mind passes 
 immediately from the sensation to that con- 
 ception and beUef of the object which we 
 have in perception, in tlie same manner as 
 it passes from signs to the tilings signified 
 by them, we have, therefore, called our 
 sensations si</)is of external objects ; finding 
 110 word more proper to express the func- 
 tion which Nature hath assigned them in 
 perception, and the relation which they 
 bear to their corresponding objects. 
 
 There is no necessity of a resemblance 
 between the sign and the thing signified ; 
 and indeed no sensation can resemble any 
 external object. But there are two things 
 necessary to our knowing things by means 
 of signs. First, That a real connection 
 between the sign and thing signified be 
 established, either by the course of nature, 
 or by the will and appointment of men. 
 When they are connected by the course of 
 nature, it is a natural sign ; when by Im- 
 man appointment, it is an artificial sign. 
 Thus, smoke is a natural sign of fire ; cer- 
 tain features are natural signs of anger : 
 but our words, whether expressed by arti- 
 culate sounds or by writing, are artificial 
 signs of our thoughts and purposes. 
 
 Another requisite to our knowing things 
 by signs is, that the appearance of the sign 
 to the mind, be followed by the conception 
 and belief of the thing signified. Without 
 this, the sign is not understood or interpreted ; 
 and, therefore, is no sign to us, however 
 fit in its own nature for that purpose. 
 
 Now, there are three ways in which the 
 mind passes from the appearance of a natu- 
 ral sign to the conception and belief of the 
 thing signified — by or'uj'mal principles of 
 our constitution, by custom^ and by reason- 
 ing. 
 
 Our original perceptions are got in the 
 first of these ways, our acquired percep- 
 tions in the second, and all that reason dis- 
 covers of the course of nature, in the third. 
 In the first of these ways, Nature, by means 
 of the sensations of touch, informs us of the 
 hardness and softness of bodies : of their 
 extension, figure, and motion ; and of that 
 space in which they move and are placed — 
 as hath been already explained in the fifth 
 chapter of this inquiry. And, in the second 
 of tJiese ways, she informs us, by means of 
 our eyes, of almost all the same things 
 
 * On perception as a revelation — "a mirarulous 
 revelation"— 6ce Jacobi's "David Hume."— H. 
 
 which originally we could perceive only by 
 touch. 
 
 In order, therefore, to understand more 
 particularly how we learn to perceive so 
 many things by the eye, which originally 
 could be perceived only by touch, it will be 
 proper. First, To point out the signs by 
 which those things are exhibited to the eye, 
 and their connection with the things signi- 
 fied by them ; and, Secondly, To consider 
 how the experience of this connection pro- 
 duces that habit by which the mind, with- 
 out any reasoning or reflectiim, passes from 
 the sign to the conception and belief of the 
 thing signified. 
 
 Of all the acquired perceptions which we 
 have by sight, the most remarkable is the 
 perception of the distance of objects from 
 the eye ; we shall, therefoie, particularly 
 consider the signs by which this perception 
 is exhibited, and only make some general 
 remarks with regard to the signs which are 
 used in other acquired perceptions. 
 
 Section XXII. 
 
 OF THE SIGNS BY WHICH AVE LEARN TO 
 PERCEIVE DISTANCE FROM THE EYE. 
 
 It was before observed in general, that 
 the original perceptions of sight are signs 
 which serve to introduce those that are 
 acquired ; but this is not to be understood 
 as if no other signs were employed for that 
 purpose. There are several motions of the 
 eyes, which, in order to distinct vision, 
 must be varied, according as the object is 
 more or less distant ; and such motions be- 
 ing by habit connected with the correspond- 
 ing distances of the object, become signs of 
 those distances.* These motions were at 
 first voluntary and unconfined ; but, as the 
 intention of nature was to produce perfect 
 and distinct vision by their means, we soon 
 learn by experience to regulate them accord- 
 ing to that intention only, without the least 
 reflection. 
 
 A ship requires a different trim for cA'ery 
 variation of the direction and strength of 
 the wind ; and, if we may be allowed to 
 borrow that word, the eyes require a differ- 
 ent trim for every degree of light, and for 
 every variation of the distance of the object, 
 while it is within certain limits. The eyes 
 are trimmed for a particular object, by con- 
 tracting certain musclesand relaxing others; 
 as the ship is trimmed for a particular wind 
 by drawing certain ropes and slackening 
 others. The sailor learns the trim of his 
 ship, as we learn the trim of our eyes, by 
 experience. A ship, although the noblest 
 machine that human art can boast, is far 
 
 « See above, p. 182, note *.— H.
 
 OF SEEING. 
 
 189 
 
 inferior to the eye in tliis respect, that it 
 requires art and ingenuity to navigate her ; 
 and a sailor mur<t laiow what rupes he must 
 pull, and what he must slaclcen, to fit her 
 to a particular wind ; but with such superior 
 wisdom is the fabric of the eye, and the 
 principles of its motion contrived, that it 
 requires no art nor ingenuity to see by it. 
 Even that part of vision which is got by 
 experience, is attained by idiots. We need 
 not know what muscles we are to contract, 
 and what we are to relax, in order to fit 
 the eye to a particular distance of the object. 
 
 But, although we are not conscious of the 
 motions we perform, in order to fit the eyes 
 to the distance of the object, we are jon- 
 scious of the effort employed in producing 
 these motions ; and probably have some 
 sensation which accompanies them, to which 
 we give as little attention as to other sensa- 
 tions. And thus, an efibrt consciously ex- 
 erted, or a sensation consequent upon that 
 efibrt, comes to be conjoined with tlie dis- 
 tance of the object which gave occasion to 
 it, and by this conjunction becomes a sign 
 of that distance. Some instances of this 
 will appear in considering the means or 
 signs by which we learn to see the distance 
 of objects from the eye. In the enumera- 
 tion of these, we agree with Dr Porterfield, 
 notwithstanding that distance from the eye, 
 in his opinion, is perceived originally, but, 
 in our opinion, by experience only. 
 
 In general, when a near object affects the 
 eye in one manner, and the same object, 
 placed at a greater distance, affects it in a 
 different manner, these various affections 
 of the eye become signs of the correspond- 
 ing distances. ' The means of perceiving 
 distance by the eye will therefore be ex- 
 plained by shewing in what various ways 
 objects affect the eye differently, according 
 to their proximity or distance. 
 
 I. It is well known, that, to see objects 
 distinctly at various distances, the form of 
 the eye must undergo some change : and 
 nature hath given us the power of adapting 
 it to near objects, by the contraction of 
 certain muscles, and to distant objects by 
 the contraction of other muscles. As to 
 the manner in which this is done, and the 
 muscular parts employed, anatomists do not 
 altogether agree. The ingenious Dr .Turin, 
 in his excellent essay on distinct and indis- 
 tinct vision, seems to have given the most 
 probable account i^f this matter ; and to him 
 I refer the reader. * 
 
 But, wliatcver be the manner in which 
 this change of tlie form of the eye is ef- 
 fected, it is certain that young people have 
 commonly the jiowcr of ada|)tiii;^ their eyes 
 
 • The mo le in which the eye is nccommoJatcd to its 
 various p?rr(|itioii«, is a subject which lias olitaineil 
 much attention from the more recent i)hyiii(ilogi>,ts. — 
 11 
 
 to all distances of the object, from six or 
 seven inches, to fifteen or sixteen feet ; so 
 as to have perfect and distinct vision at any 
 distance within these limits. From this it 
 follows, that the effort we consciously em- 
 ploy to adapt the eye to any particular dis- 
 tance of objects witlun these limits, will be 
 connected and associated with that dis- 
 tance, and will become a sign of it. When 
 the object is removed beyond the farthest 
 limit of distinct vision, it will be seen in- 
 chstinctly ; but, more or less so, according 
 as its distance is greater or less ; so that 
 the degrees of indistinctness of the object 
 may become the signs of distances consi- 
 derably beyond the farthest limit of distinct 
 vision. 
 
 If we had no other mean but this, of per- 
 ceiving distance of visible objects, the most 
 distant would not appear to be above twenty 
 or thirty feet from the eye, and the tops of 
 houses and trees would seem to touch the 
 clouds ; for, in that case, the signs of all 
 greater distances being the same, they have 
 the saiiie signification, and give the same 
 perception of distance. 
 
 But it is of more importance to observe, 
 that, because the nearest limit of distinct 
 vision in the time of youth, when we learn 
 to perceive distance by the eye, is about 
 six or seven inches, no object seen dis- 
 tinctly ever appears to be nearer than six 
 or seven inches from the eje. We can, 
 by art, make a small object appear dis- 
 tinct, when it is in reality not above half 
 an inch from the eye ; either by using a 
 single microscope, or by looking through 
 a small pin-hole in a card. AVheu, by 
 either of these means, an object is made 
 to appear distinct, however small its dis- 
 tance is in reality, it seems to be removed 
 at least to the distance of six or seven 
 inches — that is, within the limits of distinct 
 vision. 
 
 This observation is the more important, 
 because it affords the only reason we^an 
 give why an object is magnified cither by a 
 single microscope, or by being seen th.rough 
 a pin-hole ; and the only mean by which 
 we can ascertain the degree in which the 
 object will be magnified by either. Thus, 
 if the object is really half an inch distant 
 from the eye, and appears to be seven inches 
 distant, its diameter will seem to be enlarged 
 in the same jiroportion as its distance — that 
 is, fourteen times. 
 
 2. In order to direct both eyes to an 
 oliject, the ojitic axes must have a greater 
 or less inclination, according as the oliject 
 is nearer or more distant. And, although 
 we are not conscious of this iiicliuatidu, 
 yet we are conscious of the effort I'mplnyed 
 in it. By this mean we jicrceive small 
 distances more accurately than we could 
 tlo by the conformation of the eye only-
 
 190 
 
 OF THE HUMAN MIND, 
 
 And, therefore, we fiad, that those who have 
 lost the sight of one eye are apt, even 
 within arm's-length, to make mistakes in 
 the distance of objects, which are easily 
 avoided by those who see witli both eyes. 
 Such mistakes are often discovered in snuft- 
 ing a candle, in threading a needle, or in 
 filling a tea-cup.* 
 
 When a picture is seen with both eyes, 
 and at no great distance, the representation 
 appears not so natural as when it is seen 
 only with one. The intention of painting 
 being to deceive the eye, and to make things 
 appear at different distances which in reality 
 are upon the same piece of canvass, this 
 deception is not so easily put upon both 
 eyes as upon one ; because we perceive the 
 distance of visible objects more exactly and 
 determinately with two eyes than with one. 
 If the shading and relief be executed in the 
 best manner, the picture may have almost 
 the same appearance to one eye as the 
 objects themselves would have ; but it cannot 
 have the same appearance to both. This is 
 not the fault of the artist, but an unavoid- 
 able imperfection in the art. And it is 
 owing to what we just now observed, that 
 the perception we have of the distance of 
 objects by one eye is more uncertain, and 
 more liable to deception, than that which 
 we have by both. 
 
 The great impediment, and I think the 
 only invincible impediment, to that agree- 
 able deception of the eye which the painter 
 aims at, is the perception which we have of 
 the distance of visible objects from the eye, 
 partly by means of the conformation of the 
 eye, but chiefly by means of the inclmation 
 of the optic axes. If this perception could 
 be removed, I see no reason why a picture 
 might not be made so perfect as to deceive 
 the eye in reality, and to be mistaken for 
 the original object. Therefore, in order to 
 judge of the merit of a picture, we ought, 
 as much as possible, to exclude these two 
 means of perceiving the distance of the 
 several parts of it. 
 
 In order to remove this perception of dis- 
 tance, the connoisseurs in painting use a 
 method which is very proper. They look 
 at the picture with one eye, through a tube 
 which excludes the view of all other objects. 
 By this method, the principal mean whereby 
 we perceive the distance of the object — to 
 wit, the inclination of the optic axes — is en- 
 tirely excluded. I would humbly propose, 
 as an improvement of this method of view- 
 ing pictures, that the aperture of the tube 
 next to the eye should be very small. If it is 
 as small as a pin-hole, so much the better, 
 providing there be light enough to see the 
 picture clearly. The reason of this proposal 
 
 • The same remark is made by many optical wri- 
 tcrs, old and new. — H. 
 
 is, that, when we look at an object through 
 a small aperture, it will be seen distinctly, 
 whether the conformation of the eye be 
 adapted to its distance or not ; and we have 
 no mean left to judge of the distance, but 
 the light and colouring, which are in the 
 painter's i)ower. If, therefore, the artist 
 performs his part properly, the picture will 
 by this method affect the eye in the same 
 manner that the object represented would 
 do ; which is the perfection of this art. 
 
 Although this second mean of perceiving 
 the distance of visible objects be more de- 
 terminate and exact than the first, yet it 
 hath its limits, beyond which it can be of 
 no use. For when the optic axes directed 
 to an object are so nearly parallel that, in 
 directing them to an object yet more distant, 
 we are not conscious of any new effort, nor 
 have any different sensation, there our per- 
 ception of distance stops ; and, as all more 
 distant objects affect the eye in the same 
 manner, we perceive them to be at the 
 same distance. This is the reason why the 
 sun, moon, planets, and fixed stars, when 
 seen not near the horizon, appear to be all 
 at the same distance, as if they touched the 
 concave surface of a great sphere. The 
 surface of this celestial sphere is at that 
 distance beyond which all objects affect 
 the eye in the same manner. Why this 
 celestial vault appears more distant towards 
 the horizon, than towards the zenith, will 
 afterwards appear. 
 
 3. The colours of objects, according as 
 they are more distant, become more faint 
 and languid, and are tinged more with the 
 azure of the intervening atmosphere : to 
 this we may add, that their minute parts 
 become more indistinct, and their outline 
 less accurately defined. It is by these 
 means chiefly, that painters can represent 
 objects at very different distances, upon the 
 same canvass. And the diminution of the 
 magnitude of an object would not have the 
 effect of making it appear to be at a great 
 distance, without this degradation of colour, 
 and indistinctness of the outline, and of the 
 minute parts. If a painter should make a 
 human figure ten times less than other 
 human figures that are in the same piece, 
 having the colours as bright, and the out- 
 line and minute parts as accurately defined, 
 it would not have the appearance of a man 
 at a great distance, but of a pigmy or Lilli- 
 putian. 
 
 When an object hath a known variety of 
 colours, its distance is more clearly indi- 
 cated by the gradual dilution of the colours 
 into one another, than when it is of one 
 uniform colour. In the steeple which 
 stands before me at a small distance, the 
 joinings of the stones are clearly percepti- 
 ble ; the grey colour of the stone, and the 
 white cement are distinctly limited : when
 
 OF SEEING. 
 
 191 
 
 I see it at a greater distance, the joinings 
 of the stones are less distinct, and the colours 
 of the stone and of the cement begin to 
 dilute into one another : at a distance still 
 greater, the joinings disajipear altogether, 
 and the variety of colour vanishes. 
 
 In an apple-tree which stands at the dis- 
 tance of about twelve feet, covered with 
 flowers, I can perceive the figure and the 
 colour of the leaves and petals ; pieces of 
 branches, some larger, others smaller, peep- 
 ing through the intervals of the leaves — 
 some of them enlightened by the sun's rays, 
 others shaded ; and some openings of the 
 sky are perceived through the whole. When 
 I gradually remove from this tree, the ap- 
 pearance, even as to colour, changes every 
 minute. First, the smaller parts, then the 
 larger, are gradually confounded and mixed. 
 The colours of leaves, petals, branches, 
 and sky, are gradually diluted into each 
 other, and the colour of the whole becomes 
 more and more uniform. This change of 
 appearance, corresponding to the several dis- 
 tances, marks the distance more exactly than 
 if the whole object had been of one colour. 
 
 Dr Smith, in his " Optics," gives us a very 
 curious observation made by Bishop Berke- 
 ley, in his travels through Italj- and Sicily. 
 He observed. That, in those countries, 
 cities and palaces seen at a great distance 
 appeared nearer to him by several miles 
 than they really were ; and he very judi- 
 ciously imputed it to this cause, That the 
 purity of the ItaUan and Sicilian air, gave 
 to very distant objects that degree of 
 brightness and distinctness which, in the 
 grosser air of his own country, was to be 
 seen only in those that are near. The 
 purity of the Italian air hath been assigned 
 as the reason why the Italian painters 
 commonly give a more lively colour to the 
 sky than the Flemish. Ought they not, 
 for the same reason, to give less degrad- 
 ation of the colours, and less indistinct- 
 ness of the minute parts, in the representa- 
 tion of very distant objects ? 
 
 It is very certain that, as in air uncom- 
 monly pure, we are apt to think visible 
 objects nearer and less than they really 
 are, so, in air uncommonly foggy, we are 
 apt to think them more distant and larger 
 than the trutli. Walking by the sea-side 
 in a thick fog, I see an object which seems 
 to me to be a man on horseback, and at 
 the distance of al)out half a mile. My com- 
 panion, who has better eyes, or is more 
 accustomed to see such objects in such cir- 
 cumstances, assures nie that it is a sea- 
 gull, and not a man on horseback, U])on 
 a second view, I imnuMlIately assent to his 
 opinion ; and now it ujjpcars to me to be a 
 Bea -gull, and at tlie distance only of seventy 
 or eighty yards. The mistalic! made on this 
 occasion, and tlie correction of it, are both 
 
 so sudden, that we are at a loss whether 
 to call them by the name of judgment, or 
 by that of simple perceplion. 
 
 It is not worth while to dispute about 
 names • but it is evident that my belief, 
 both first and last, was produced rather by 
 signs than by arguments, and that the 
 mind proceeded to the conclusion in both 
 cases by habit, and not by ratiochiation. 
 And the process of the mind seems to have 
 been this — First, Not knowing, or not 
 minding, the effect of a foggy air on the vis- 
 ible appearance of objects, the object seems 
 to me to have that degradation of colour, 
 and that indistinctness of the outline, which 
 oVijects have at the distance of half a mile ; 
 therefore, from the visible appearance as a 
 sign, I immediately proceed to the belief 
 that the object is half a mile distant. 
 Then, this distance, together with the vis- 
 ible magnitude, signify to me the real 
 magnitude, which, supposing the distance 
 to be half a mile, must be equal to that 
 of a man on horseback ; and the figure, 
 considering the indistinctness of the outline, 
 agrees with that of a man on horseback. 
 Thus the deception is brought about. But 
 when I am assured that it is a sea-gull, the 
 real magnitude of a sea-gull, together with 
 the visible magnitude presented to the eye, 
 immediately suggest the distance, which, 
 in this case, cannot be above seventy or 
 eighty yards : the indistinctness of the 
 figure likewise suggests the fogginess of the 
 air as its cause ; and now the whole chain 
 of signs, and things signified, seems stronger 
 and better connected than it was before ; 
 the half mile vanishes to eighty yards ; 
 the man on horseback dwindles to a sea- 
 gull ; I get a new perception, and wonder 
 how I got the former, or what is become of 
 it ; for it is now so entirely gone, that I 
 cannot recover it. 
 
 It ought to be observed that, in order to 
 produce such deceptions from the clearness 
 or fogginess of the air, it must be uncom- 
 monly dear or uncommonly foggy ; for we 
 learn, from experience, to make allowance 
 for that variety of constitutions of the air 
 which wc have been accustomed to observe, 
 and of which we are aware. Bishop 
 Berkeley therefore connnitted a mistake, 
 when he attributed the large appearance of 
 the horizontal moon to the faintness of her 
 light, occasioned by its passing througli a 
 larger tract of atmosphere :* for we are so 
 much accustomed to see the moon in all 
 degrees of faintness and brightness, from 
 the greatest to the least, that we learn to 
 make allowance for it ; and do not imagine 
 her magnitude increased ))y the faintniss of 
 her a])|)carance. Besides, it is certain that 
 the horizontal moon seen through a tube 
 
 • 'I'hii)fX|lanation wasnotoriginalto Rcrkctcy.— H.
 
 192 
 
 OF THE HUMAN MIND. 
 
 wliich cuts off the view of the interjacent 
 ground, and of all terrestrial nbjects, loses 
 all that unusual appearance of magnitude. 
 
 4. We frequently perceive the distance 
 of objects, by means of intervening or con- 
 tiguous olijects, whose distance or magni- 
 tude is otherwise known. When I perceive 
 certain fields or tracts of ground to lie be- 
 tween me and an object, it is evident that 
 these may become signs of its distance. 
 And although we have no particular in- 
 formation of the dimensions of such fields 
 or tracts, yet their similitude to others which 
 we know, suggests their dimensions. 
 
 We are so much accustomed to measure 
 with our eye the ground which Me travel, 
 and to compare the judgments of distances 
 formed by sight, with our experience or in- 
 formation, that we learn by degrees, in this 
 way, to form a more accurate judgment of 
 the distance of terrestrial objects, than we 
 could do by any of the means before men- 
 tioned. An object placed upon the top of 
 a high building, appears much less than 
 when placed upon the ground, at the same 
 distance. When it stands upon the ground, 
 the intervening tract of ground serves as a 
 sign of its distjince ; and the distance, to- 
 gether with the visible magnitude, serves 
 as a sign of its real magnitude. But when 
 the object is placed on high, this sign of its 
 distance is taken away : the remaining 
 signs lead us to place it at a less distance ; 
 and this less distance, together with the 
 visible magnitude, becomes a sign of a less 
 real magnitude. 
 
 The two first means we have mentioned, 
 would never of themselves make a visible 
 object appear above a hundred and fifty, 
 or two hundred feet, distant ; because, be- 
 yond that there is no sensible change, either 
 of the conformation of the eyes, or of the 
 inclination of their axes. The third mean 
 is but a vague and undeterminate sign, 
 when applied to distances above two or three 
 hundred feet, unless we know the real colour 
 and figure of the object ; and the fifth 
 mean, to be afterwards mentioned, can 
 only be applied to objects which are fami- 
 liar, or whose real magnitude is known. 
 Hence it follows, that, when unknown ob- 
 jects, upon or near the surface of the earth, 
 are perceived to be at the distance of some 
 miles, it is always by this fourth mean that 
 we are led to that conclusion. 
 
 Dr Smith hath observed, very justly, that 
 the known distance of the terrestrial objects 
 which terminate our view, makes that part 
 of the sky which is towards the horizon 
 appear more distant than that which is to- 
 wards the zenith. Hence it comes to pass, 
 that the a[)parent figure of the sky is not 
 that of a hemisphere, but rather a less seg- 
 ment of a sphere. And, hence, likewise, 
 it comes to pass, that the diameter of the 
 
 sun or moon, or the distance between two 
 fixed stars, seen contiguous to a hill, or to 
 any distant terrestrial object, appears much 
 greater than when no such object strikes 
 the eye at the same time. 
 
 These observations have been sufficiently 
 explained and confirmed by Dr Smith. I 
 beg leave to add, that, when the visible 
 horizon is terminated by very distant ob- 
 jects, the celestial vault seems to be en- 
 larged in all its dimensions. When 1 view 
 it from a confined street or lane, it bears 
 some proportion to the buildings that sur- 
 round me ; but,, when I view it from a large 
 plain, terminated on all hands by hills which 
 rise one above another to the distance of 
 twenty miles from the eye, methinks I fcee 
 a new heaven, whose magnificence declares 
 the greatness of its Author, and puts every 
 human edifice out of countenance ; for now 
 the lofty spires and the gorgeous palaces 
 shrink into nothing before it, and bear no 
 more proportion to the celestial dome than 
 their makers bear to its Maker. 
 
 5. There remains another mean by which 
 we perceive the distance of visible objects — 
 and that is, the diminution of their visible 
 or apparent magnitude. By experience, I 
 know what figure a man, or any other known 
 object, makes to my eye at the distance of 
 ten feet — I perceive the gradual and pro- 
 portional diminution of this visible figure, at 
 the distance of twenty, forty, a hundred 
 feet, and at greater distances, until it vanish 
 altogether. Hence a certain visible magni- 
 tude of a known object becomes the sign of 
 a certain determinate distance, and carries 
 along with it the conception and belief of 
 that distance. 
 
 In this process of the mind, the sign is 
 not a sensation ; it is an original percep- 
 tion. We perceive the visible figure and 
 visible magnitude of the object, by the ori- 
 ginal power^ of vision ; but the visible figure 
 is used only as a sign of the real figure, and 
 the visible magnitude is used only as a sign 
 either of the distance, or of the real magni- 
 tude, of the object ; and, therefore, these 
 original perceptions, like other mere signs, 
 pass through the mind without any atten- 
 tion or reflection. 
 
 This last mean of perceiving the dis- 
 tance of known objects, serves to explain 
 some very remarkable phsenomena in op- 
 tics, which would otherwise appear very 
 mysterious. When we view objects of 
 known dimensions through optical glasses, 
 there is no other mean left of determining 
 their distance, but this fifth. Hence it 
 follows, that known objects seen through 
 glasses, must seem to be brought nearer, in 
 proportion to the magnifying power of the 
 glass, or to be removed to a greater distance, 
 in proportion to the diminishing power of 
 the glass.
 
 OF SEEING. 
 
 193 
 
 If a man who had never before seen ob- 
 jects tlirough a telescope, were told that 
 the telescope, which he is about to use, mag- 
 nifies the diameter of the object ten times ; 
 when he looks througli this telescope at a 
 man six feet high, what would he expect 
 to see ? Surely he would very naturally 
 expect to see a giant sixty feet high. But 
 he sees no such tliinir. The man appears 
 no more than six feet high, and conse- 
 quently no bigger than he really is ; but he 
 appears ten times nearer than he is. The 
 telescope indeed magnifies the image of 
 this man upon the retina ten times in dia- 
 meter, and must, therefore, magnify his 
 visible figure in the same proportion ; and, 
 as we have been accustomed to see him of 
 this visible magnitude when he was ten 
 times nearer than he is presently,* and in 
 no other case, tliis visible magnitude, there- 
 fore, suggests the conception and belief of 
 tliat distance of the object with which it 
 hath been always connected. We have 
 been accustomed to conceive this amplifi- 
 cation of the visible figure of a known ob- 
 ject, only as the effect or sign of its being 
 brought nearer : and we have annexed a 
 certain determinate distance to every de- 
 gree of visible magnitude of the object ; 
 and, therefore, any particular degree of vi- 
 sible magnitude, whether seen by the naked 
 eye or by glasses, brings along with it the 
 conception and belief of the distance which 
 corresponds to it. This is the reason 
 why a telescope seems not to magnify known 
 objects, but to bring them nearer to the 
 eye. 
 
 When we look through a pin-hole, or a 
 single microscope, at an object which is 
 half an inch from the eye, the picture of 
 the object upon the retina is not enlarged, 
 but only rendered distinct ; neither is the 
 visible figure enlarged: yet the ob ect ap- 
 pears to the eye twelve or fourteen times 
 more distant, and as many times larger in 
 diameter, than it really is. Such a tele- 
 scope as we have mentioned amplifies the 
 image on the reliiui, and the visible figure 
 of the object, ten times in diameter, and yet 
 makes it seem no bigger, but only ten times 
 nearer. These appearances had been long 
 observed by the writers on o])tics ; they tor- 
 tured their invention to find the causes of 
 them from optical principles ; but in vain : 
 they must be resolved into habits of perce[)- 
 tion, which arc ac((uir(Ml by custDin, but 
 are apt to bo mistak(!ii for original perci-p- 
 tions. The JJishoi) of Cloyi;e first furnished 
 the world with the proper key for opening 
 up these mysterious appearances ; but he 
 made considerable mistakes in the applica- 
 tion of it. Dr Smith, in his elaborate and ju- 
 dicious treatise (jf 'Optics," hath applied it 
 
 • Sec note ♦ p. OR, a.— H. 
 
 to the apparent distance of objects seen with 
 glasses, and to the apparent figure of the 
 heavens, with such happy success, that there 
 can be no more doubt about the causes of 
 these phenomena. 
 
 Section XXIII. 
 
 OV THE SIGNS USED IN OTHER ACQUIRED PER- 
 CEPTIONS. 
 
 The distance of objects from the eye is 
 the most important lesson in vision. Many 
 others are easily learned in consequence of 
 it. The distance of the object, joined with 
 its visible magnitude, is a sign of its real 
 magnitude : and the distance of the several 
 parts of an object, joined with its visible 
 figure, becomes a sign of its real figure. 
 Thus, when I look at a globe which stands 
 before me, by the original powers of sight 
 I perceive only something of a circular 
 form, variously coloured. The visible figure 
 hath no distance from the eye, no convexitv, 
 nor hath it three dimensions ; even its length 
 and breadth are inca])able of being mea- 
 sured by inches, feet, or other linear mea- 
 sures. But, when I have learned to per- 
 ceive the distance of every part of this 
 object from the eye, this perception gives it 
 convexity, and a spherical figure ; and adds 
 a third dimension to that which had but 
 two before. The distance of the whole 
 object makes me likewise perceive the real 
 magnitude ; for, being accustomed to ob- 
 serve how an inch or a foot of length aftects 
 the eye at that distance, I plainly perceive 
 by my eye the linear dimensions of the 
 globe, and can attirm with certainty that 
 its diameter is about one foot and three 
 inches. 
 
 It was shewn in the 7th section of 
 this chapter that the visible figure of a 
 body may, by mathematical reasoning, be 
 inferi-ed from its real figure, distance, and 
 position, with regard to the eye: in like 
 inannc!-, we may, by mathematical reason- 
 ing, from the visible figure, together with 
 the distance of the several parts of it from 
 the eye, infer the real figure and position. 
 But this last inference is not commonly 
 made by mathematical reasoning, nor, in- 
 deed, by reasoning of any kind, but by cus- 
 tom. 
 
 The original appearance which the colour 
 of an object makes to the eye, is a sensa- 
 tion for which we have no name, because 
 it is used merely as a sign, and is never made 
 an object of attention in common life: but 
 this appearance, according to the different, 
 circumstances, signifies various things. If 
 .a i)iece of cloth, of one uniform cdleur, is 
 laid so that [lart f)f it is in the sun, and pait 
 in the sha<le, the n|ipe;i ranee of colour, iu
 
 194 
 
 OF THE HUMAN MIND. 
 
 these different parts, is very difi'erent : yet 
 we perceive the colour to he the same ; we 
 interpret tlie variety of appearance as a 
 sign of hght and shade, and not as a sign 
 of real difierence in colour. But, if the 
 eye could be so far deceived as not to per- 
 ceive the difference of light in the two 
 parts of the cloth, we should, in that case, 
 interpret the variety of appearance to signify 
 a variety of colour in the parts of the cloth. 
 Again, if we suppose a piece of cloth 
 placed as before, but having the shaded part 
 so much brighter in the colour that it gives 
 the same appearance to the eye as the more 
 enlightened part, the sameness of appear- 
 ance will here be interpreted to signify a 
 variety of colour, because we shall make 
 allowance for the effect of light and shade. 
 When the real colour of an object is 
 known, the appearance of it indicates, in 
 some circumstances, the degree of light 
 or shade ; in others, the colour of the cir- 
 cumambient bodies, whose rays are reflected 
 by it ; and, in other circumstances, it indi- 
 cates the distance or proximity of the ob- 
 ject — as was observed in the last section ; 
 and by means of these, many other things 
 are suggested to the mind. Thus, an un- 
 usual appearance in the colour of familiar 
 objects may be the diagnostic of a disease 
 in the spectator. The appearance of things 
 in my room may indicate sunshine or cloudy 
 weather, the earth covered with snow or 
 blackened with rain. It hath been ob- 
 served, that the colour of the sky, in a 
 piece of painting, may indicate the country 
 of the painter, because the Italian sky is 
 really of a different colour from the Flemish. 
 It was already observed, that the original 
 and acquired perceptions which we have 
 by our senses, are the language of nature 
 to man, which, in many respects, hath a 
 great affinity to human languages. The 
 instances which we have given of acquired 
 perceptions, suggest this affinity — that, as, 
 in human languages, ambiguities are often 
 found, so this language of nature in our ac- 
 quired perceptions is not exempted from 
 them. We have seen, in vision particu- 
 larly, that the same appearance to the eye, 
 may, in different circumstances, indicate 
 different things. Therefore, when the cir- 
 cumstances are unknown upon which the 
 interpretation of the signs depends, their 
 meaning must be ambiguous ; and when the 
 circumstances are mistaken, the meaning 
 of the signs must also be mistaken. 
 
 This is the case in all the phajnomena 
 which we call fallacies of 'he senses ; and 
 particularly in those which are called 
 fallacies in vision. The appearance of 
 things to the eye always corresponds to the 
 fixed laws of Nature ; therefore, if we speak 
 properly, there is no fallacy in the senses. 
 Nature always speaketh the same language, 
 
 and useth the same signs in the same cir- 
 cumstances ; but we sometimes mistake 
 the meaning of the signs, either through 
 ignorance of th.e laws of Nature, or through 
 ignorance of the circumstances which attend 
 the signs.* 
 
 To a man unacquainted with the prin- 
 ciples of optics, almost every experiment 
 that is made with the prism, with the magic 
 lanthorn, with the telescope, with the mi- 
 croscope, seems to produce some fallacy in 
 vision. Even the appearance of a common 
 mirror, to one altogether unacquainted with 
 the effects of it, would seem most remark- 
 ably fallacious. For how can a man be 
 more imposed upon, than in seeing that 
 belbre him which is really behind him ? 
 How can he be more imposed upon, than 
 in being made to see himself several yards 
 removed from himself ? Yet children, 
 even before they can speak their mother- 
 tongue, learn not to be deceived by these 
 appearances. These, as well as all the 
 other surprising appearances produced by 
 optical glasses, are a part of the visual lan- 
 guage, and, to those who understand the 
 laws of Nature concerning light and colours, 
 are in nowise fallacious, but have a dis- 
 tinct and true meanmg. 
 
 Section XXIV. 
 
 OF THE ANALOGY BETWEEN PERCEPTION 
 AND THE CREDIT WE GIVE TO HUMAN 
 TESTIMONY. -f 
 
 The objects of human knowledge are in- 
 numerable ; but the channels by which it 
 is conveyed to the mind are few. Among 
 these, the perception of external things by 
 our senses, and the informations which we 
 receive upon human testimony, are not the 
 least considerable ; and so remarkable is 
 the analogy between these two, and the 
 analogy between the prihciples of the mind 
 which are subservient to the one and those 
 which are subservient to the other, that, 
 without further apology, we shall consider 
 them together. 
 
 In the testimony of Nature given by the 
 senses, as well as in human testimony given 
 by language, things are signified to us by 
 signs : and in one as well as the other, the 
 mind, either by original principles or by 
 custom, passes from the sign to the concep- 
 tion and belief of the things signified. 
 
 We have distinguished our perceptions 
 
 • This is the doctrine of Aristotle ; who holds 
 that the senses never deceive us in relation to their 
 proper objects. — H. 
 
 t Compare Mr Stewart's " Flements," vo'. 1 , 
 eh. ii., ^ 4, p. 247. Second edition. Campljell 
 "On Miracles," Part 1., \ 1. Smith's " 1 heory o 
 Moral Sentiment," vol II., p. 38<J. Sixth edition. — 
 H.
 
 OF SEEING. 
 
 195 
 
 into original and acquired ; and language, 
 into natural and artificial. Between 
 acquired perception and artificial language, 
 there is a great analogy ; but still a greater 
 between original perception and natural 
 language. 
 
 The signs in original perception are sens- 
 ations, of which Nature hath given us a great 
 variety, suited to the variety of the things 
 signified by them. Nature hath established 
 a real connection between the signs and the 
 things signified ; andNature hath also taught 
 us the interpretation of the signs — so that, 
 previous to experience, the sign suggests 
 the thing signified, and create the belief of 
 it. 
 
 The signs in natural language are features 
 of the face, gestures of the body, and modu- 
 lations of the voice ; the variety of which is 
 suited to the variety of the things signified 
 by them. Nature hath established a real 
 connection between these signs, and the 
 thoughts and dispositions of the mind which 
 are signified by them ; and Nature hath 
 taught us the interpretation of these signs ; 
 so that, previous to experience, the signs 
 suggest the thmg signified, and create the 
 belief of it. 
 
 A man in company, without doing good 
 or evil, without uttering an articulate sound, 
 may behave himself gracefully, civilly, 
 politely ; or, on the contrary, meanly, 
 rudely, and impertinently. We see the 
 dispositions of his mind by their natural 
 signs in his countenance and behaviour, in 
 the same manner as we perceive the figure 
 and other qualities of bodies by the sensa- 
 tions which nature hath connected with 
 tiiem. 
 
 The signs in the natural language of the 
 human countenance and behaviour, as well 
 as the signs in our original perceptions, 
 have the same signification in all climates 
 and in all nations ; and the skill of inter- 
 preting them is not acquired, but innate. 
 
 In acquired perception, the signs arc 
 either sensations, or things whicli we per- 
 ceive by means of sensations. The con- 
 nection between the sign and the thing sig- 
 nified, is established by nature ; and we 
 discover this connection by experience ; 
 but not without the aid of our original per- 
 ceptions, or of those which we have already 
 acquired. After this connection is dis- 
 covered, the sign, in like manner as in 
 original perception, always suggests the 
 things signified, and creates the belief of 
 it. 
 
 In artificial language, the signs are arti- 
 culate sounds, whose connection with the 
 things signified by them, is establislied by 
 the will of men ; and, in learning our 
 mother tongue, we discover tiiis connection 
 by experience ; );ut not without the aid of 
 natural language, or of wliat we had before 
 
 attained of artificial language. And, after 
 this connection is discovered, the sign, as 
 in natural language, always suggests the 
 thing signified, and creates the belief of it. 
 
 Our original perceptions are few, com- 
 pared with the acquired ; but, without the 
 former, we could not possibly attain the 
 latter. In like manner, natural language 
 is scanty, compared with artificial ; but, 
 without the former, we could not possibly 
 attain the latter. 
 
 Our original perceptions, as well as the 
 natural language of human features and 
 gestures, must be resolved into particular 
 princip'es of the human constitution. Thus, 
 it is by one particular principle of our con- 
 stitution that certain features express anger; 
 and, by another particular principle, that 
 certam features express benevolence. It is, 
 in like manner, by one particular principle 
 of our constitution that a certain sensation 
 signifies hardness in the body which I 
 handle ; and it is by another particular 
 principle that a certain sensation signifies 
 motion in that body. 
 
 But our acquired perceptions, and the 
 information we receive by means of arti- 
 ficial language, must be resolved into gene- 
 ral principles of the human constitution. 
 When a painter perceives that this picture 
 is the work of Kaphael, that the work of 
 Titian ; a jeweller, that this is a true dia- 
 mond, that a counterfeit ; a sailor, that this 
 is a ship of five hundred ton, that of four 
 hundred ; these different acquired percep- 
 tions are produced by the same general 
 principles of the human mind, which have 
 a different operation in the same person 
 according as they are variously applied, and 
 in different persons according to the divers- 
 ity of their education and manner of life. 
 In like manner, when certain articulate 
 sounds convey to my mind the knowledge of 
 the battle of Pharsalia, and others, the 
 knowledge of the battle of Poltowa — when a 
 Frenchman and an Englishman receive the 
 same information by different articulate 
 sounds — the siirns used in these different 
 cases, produce the knowledge and belief of 
 the things signified, by means of the same 
 general principles of the human constitu- 
 tion. 
 
 Now, if we compare the general prin- 
 ciples of our constitution, which fit us for 
 receiving information from our fellow-crea- 
 tures by language, with the general prin- 
 ciples which fit us for acquiring tlie per- 
 ception of things by our senses, we shall 
 find them to be very similar in their nature 
 and manner of operation. 
 
 When we begin to learn our mother- 
 tongue, we perceive, by the help of natural 
 language, that they who s]i<ak to us use 
 certain soiuids to cxi)re.ss certain things 
 we imitate the same sounds wiien we would 
 
 () 2
 
 196 
 
 OF THE HUMAN MIND. 
 
 express the same things ; and find that we 
 arc understood. 
 
 But here a difficulty occurs which merits 
 our attention, because the sohition of it 
 ieads to some original principles of the Im- 
 man mind, which are of great importance, 
 and of very extensive influence. We know 
 by experience that men have used such 
 words to express such things ; but all ex- 
 perience is of the p'lst, and can, of itself, 
 give no notion or belief of what va futurr. 
 How come we, then, to believe, and to rely 
 upon it with assurance, that men, who have 
 it in their power to do otherwise, will con- 
 tinue to use the same words when they 
 think the same things ? Whence comes 
 this knowledge and belief— this foresight, we 
 ought rather to call it — of the future and 
 voluntary actions of our fellow-creatures ? 
 Have they promised that they will never 
 impose upon us by equivocation or falsehood ? 
 No, they have not. And, if they had, tliis 
 would not solve the difficulty ; for sucli 
 promise must be expressed by words or by 
 other signs ; and, before we can rely upon 
 it, we must be assured that they put the 
 usual meaning upon the signs which express 
 that promise. No man of common sense 
 ever thought of taking a man's own word 
 for his honesty ; and it is evident that we 
 take his veracity for granted when we lay 
 any stress upon his' word or promise. I 
 might add, that this reliance upon tlie de- 
 clarations and testimony of men is found 
 in children long before they know what a 
 promise is. 
 
 There is, therefore, in the human mind 
 an early anticipation, neither derived from 
 experience, nor from reason, nor from any 
 compact or promise, that our fellow-crea- 
 tures will use the same signs in language, 
 when they have the same sentiments. 
 
 This is, in reality, a kind of prescience 
 of human actions ; and it seems to me to 
 be an original principle of the human con- 
 stitution, without which we should be in- 
 capable of language, and consequently in- 
 capable of instruction. 
 
 The wise and beneficent Author of Nn- 
 ture, who intended that we should be social 
 creatures, and that we should receive the 
 greatest and most important part of our 
 knowledge by the information of others, 
 hath, for these purposes, implanted in our 
 natures two principles that tally with each 
 other. 
 
 The first of these principles is, a pro- 
 pensity to speak truth, and to use the signs 
 of language so as to convey our real sen- 
 timents. This principle has a powerful 
 operation, even in the greatest liars ; for 
 where they lie once, they speak truth a 
 hundred times. Trutli is always uppermost, 
 and is the natural issue of the mind. It 
 requires no art or training, no inducement 
 
 or temptat'on, but only that we yield to a 
 natural impulse. Lying, on the contrary, 
 is doing violence to our nature ; and is 
 never practised, even by the worst men, 
 without some temptation. Speaking truth 
 is like using our natural food, which we 
 would do from appetite, although it an- 
 swered no end ; but lying is like taking 
 physic, which is nauseous to the taste, and 
 wliich no man takes but for some end which 
 he cannot otherwise attain. 
 
 If it should be objected, That men may 
 be influenced by moral or political consider- 
 ations to speak truth, and, therefore, that 
 their doing so is no proof of such an origi- 
 nal principle as we have mentioned — I 
 answer. First, That moral or political con- 
 siderations can have no influence until we 
 arrive at years of understanding and reflec- 
 tion ; and it is certain, from experience, 
 that children keep to truth invariably, be- 
 fore they are capable of being influenced by 
 such considerations. Secondly, When we 
 are influenced by moral or political con- 
 siderations, we must be conscious of that 
 influence, and capable of perceiving it upon 
 reflection. Now, when I reflect upon my 
 actions most attentively, I am not conscious 
 that, in speaking truth, I am influenced on 
 ordinary occasions by any motive, moral or 
 political. I find that truth is always at tlie 
 door of my lips, and goes forth sponta- 
 neously, if not held back. It requires 
 neither good nor bad intention to bring it 
 forth, but only that I be artless and unde- 
 signing. There may indeed be temjitations 
 to falsehood, which would be too strong for 
 the natural principle of veracity, unaided 
 by principles of honour or virtue ; but 
 where there is no such temptation, we speak 
 truth by instinct— and tliLs instinct is the 
 principle I have been explaining. 
 
 By this instinct, a real connection is 
 formed between our words and our thoughts, 
 and thereby the former become fit to be 
 signs of the latter, which they could not 
 otherwise be. And although this connec- 
 tion is broken in every instance of lying 
 and equivocation, yet these instances being 
 comparatively few, the authority of human 
 testimony is only weakened by them, but 
 not destroyed. 
 
 Another original principle implanted in 
 us by the Supreme Being, is a disposition 
 to confide in the veracity of others, and to 
 believe what they tell us- This is the 
 counterpart to the former ; and, as that 
 maybe called the principle of veracity, v.e 
 shall, for want of a more proper name, call 
 this the principle of credulity. It is un- 
 limited in children, until they meet with 
 instances of deceit and falsehood ; and it 
 retains a very considerable degree of strengtli 
 through' life. 
 
 If Nature had left the mind of the speakf^r-
 
 OF SEEING. 
 
 It7 
 
 in tejnilibrio, witliout any inclination to 
 the side of trutli more tlian to that of false- 
 : hood, children would he as often as they 
 speak truth, until reason was so far ripened 
 _^ : as to suggest the imprudence of lying, or 
 — conscience, as to suggest its immorality. 
 And if Nature had left the mind of the 
 hearer in cequilil/rio, without any inclina- 
 tion to the side of belief more than to that 
 of disbelief, we should take no man's word 
 until we had positive evidence that he 
 spoke truth. His testimony would, in this 
 case, have no more authority than his 
 dreams^ which may be true or false, but 
 no man is disposed to believe them, on this 
 account, that they were dreamed. It is 
 evident that, in the matter of testimony, 
 the balance of human judgment is by nature 
 inclined to the side of belief ; and turns to 
 that side of itself, when tliere is nothing 
 put into the opposite scale. If it was not 
 so, no proposition that is uttered in dis- 
 course would be believed, until it was 
 examined and tried by reason ; and most 
 men would be unable to tind reasons for 
 believing the thousandth part of what is 
 told them. Such distrust and incredulity 
 would deprive us of the greatest benefits of 
 society, and place us in a worse condition 
 than that of savages. 
 
 Children, on this supposition, would be 
 absolutely incredulous, and, therefore, ab- 
 solutely incapable of instruction : those who 
 had little knowledge of human life, and of 
 the manners and characters of men, would 
 be in the next degree incredulous : and the 
 most credulous men would be those of 
 greatest experience, and of the deepest 
 penetration ; because, in many cases, they 
 would be able to find good reasons for 
 believing testimony, which the weak and 
 the ignorant could not discover. 
 
 In a word, if credality were the effect of 
 reasoning and experience, it must grow up 
 L and gather strength, in the same proportion 
 T as reason and experience do. But, if it is 
 the gift of Nature, it will be strongest in 
 ciiildhood, and limited and restrained by 
 experience ; and the most suj)erficial view 
 of human life shews, that the last is really 
 the case, and not the first." 
 
 It is the intention of Nature, that wc 
 should be carried in arms before we arc able 
 to walk upon our legs ; and it is likewise 
 the intention of Nature, that our belief 
 should be guided by the authority and rea- 
 son of others, Iiefore it can be guided by 
 our own reason. The weakness of the in- 
 fant, and the natural afi'ection of the mother, 
 plainly indicate the former; and the natural 
 credulity of youth, and authority of ago, as 
 plainly indicate the latter. The infant, by 
 
 • See.cfln/rrt, Pricntley'i" Kxamina»io 1," p. 8(5. 
 " Brown't Lcct." Icct. Ixxxiv. 
 
 proper nursing and care, acquires strength 
 to walk without support. Reason hath 
 likewise her infancy, when she must be 
 carried in arms : then she leans entirely 
 upon authority, by natural instinct, as if 
 she was conscious of her own weakness ; 
 and, without this support, she becomes ver- 
 tiginous. When brought to maturity by 
 proper culture, she begins to feel her own 
 strength, and leans less upon the reason of 
 others ; she learns to suspect testimony in 
 some cases, and to disbelieve it in others ; 
 and sets bounds to that authority to which 
 she was at first entirely subject. But still 
 to the end of life, she finds a necessity ot 
 borrowing light from testimony, where she 
 has none within herself, and of leaning, 
 in some degree, upon the reason of others, 
 where she is conscious of her own unbe- 
 cility. 
 
 And as, in many instances. Reason, even 
 in lier maturity, borrows aid from testi- 
 mony, so in others she mutually gives aid 
 to it, and strengthens its authority. For. 
 as we find good reason to reject testunony in 
 some cases, so in others we fiud good reason 
 to rely upon it with perfect security, in our 
 most important concerns. The character, 
 the number, and the disinterestedness of 
 witnesses, the impossibility of collusion, and 
 the incredibility of tli^ir concurring in their 
 testimony without collusion, may give an 
 irresistible strength to testimony, compared 
 to which its native and intrmsic authority 
 is very inconsiderable. 
 
 Having now considered the general prin- 
 ciples of the human mind which fit us for 
 receiving information from our fellow-crea- 
 tures, by the means of language, let us next 
 consider the general principles which fit us 
 for receiving the information of Nature by 
 our acquired perceptions. 
 
 It is undeniable, and indeed is acknow- 
 ledged by all, that when we have found two 
 things to have been constantly conjoined in 
 the course of nature, the appearance of one 
 of them is immediately followed by the con- 
 ception and belief of the other. The for- 
 mer becomes a natural sign of the latter; 
 andtlie knowledge of their constant conjunc- 
 tion in time past, whether got by experiLnce 
 or otherwise, is sufficient to make us rely 
 with assurance upon the continuance of that 
 conjunction. 
 
 'i'his process of the human mind is so 
 familiar that we never think of incjuiring 
 into the principles upon which it is founded. 
 Wc are apt to conceive it as a self-evident 
 tiMth, that what is to come must be similar 
 to what is past. Thus, if a certain degree 
 of cold freezes water to-day, and has been 
 known to do so in all time past, we havo 
 no doubt but the same degree of cold will 
 freeze water to-morrow, or a year hence. 
 'I'liiit this is a truth which all men believe lis
 
 198 
 
 OF THE HUMAN MIND. 
 
 soon as they understand it, I readily admit ; 
 but the question is, Whence does its evi- 
 dence arise ? Not from comparing the 
 ideas, surely. For, when I compare the 
 idea of cold with that of water hardened 
 into a transparent solid body, I can per- 
 ceive no connection between them : no man 
 can shew the one to be the necessary effect 
 of the other ; no man can give a shadow of 
 reason why Nature hath conjoined them. 
 But do we not learn their conjunction from 
 experience ? True ; experience informs 
 us that they have been conjoined in time 
 past ; but no man ever had any experience 
 of what is future : and this is the very 
 question to be resolved. How we come to 
 believe that the future will be like the 
 past ? Hath the Author of nature pro- 
 mised this ? Or were we admitted to his 
 council, when he established the present 
 laws of nature, and determined the time 
 of their continuance. No, surely. In- 
 deed, if we believe that there is a vnse and 
 good Autlior of nature, we may see a good 
 reason why he should continue the same 
 laws of nature, and the same connections 
 of things, for a long time : because, if he 
 did otherwise, we could learn nothing from 
 what is past, and all our experience would 
 be of no use to us. But, though this con- 
 sideration, when we come to the use of rea- 
 son, may confirm our belief of the contin- 
 uance of the present course of nature, it 
 is certain that it did not give rise to this 
 belief ; for children and idiots have this be- 
 lief as soon as they know that fire will burn 
 them. It must, therefore, be the eff'ect of 
 instinct, not of reason. * 
 
 The wise Author of our nature intended, 
 that a great and necessary part of our know- 
 ledge should be derived from experience, 
 before we are capable of reasoning, and he 
 hath provided means perfectly adequate to 
 this intention. For, First, He governs nature 
 by fixed laws, so that we find innumerable 
 connections of things which continue from 
 age to age. Without this stability of the 
 course of nature, there could be no experi- 
 ence ; or, it would be a false guide, and lead 
 us into error and mischief. If there were 
 not a principle of veracity in the human 
 mind, men's words would not be signs of 
 their thoughts : and if there were no regu- 
 larity in the course of nature, no one thing 
 could be a natural sign of another. Se- 
 condly, He hath implanted in human minds 
 an original principle by which we believe 
 and expect the continuance of the course of 
 nature, and the continuance of those connec- 
 
 * Compare Stewart's " Elements," vol. I,, chap, 
 iv , ^ 5, p. H)b, sixth edition ; " Philosophical Essays,'' 
 p.7t, sqq., fourth edition; Rover Collard, in Jouf. 
 froy's " Oeuvreg de Reid," 1. IV , p. 279, sqq. ; with 
 Priestley's " Examination," p. 86, sqq. I merely 
 refer to works relative to Keid's doctrine. — H. 
 
 tions which we have observed in time past. 
 It is by this general principle of our nature, 
 that, when two things have been found con- 
 nected in time past, the ajipearance of the 
 one produces the belief of the other. 
 
 I tliink the ingenious author of the "Trea- 
 tise of Human Nature" first observed. That 
 our belief of the continuance of the laws of 
 nature cannot be founded either upon know- 
 ledge or probability : but, far from conceiv- 
 ing it to be an original principle of the 
 mind, he endeavours to account for it from 
 his favourite hypothesis, That belief is no- 
 thing but a certain degree of vivacity in 
 the idea of the thing believed. I made a 
 remark upon this curious hypothesis in the 
 second chapter, and shall now make an- 
 other. 
 
 The belief which we have in perception, 
 is a belief of the present existence of the 
 object; that which we have in memory, is 
 a belief of its past existence ; the belief of 
 which we are now speaking is a belief of its 
 future existence ; and iu imagination there 
 is no belief at all. Now, I would gladly 
 know of this author, how one degree of 
 vivacity fixes the existence of the object to 
 the present moment ; another carries it 
 back to time past ; a third, taking a con- 
 trary direction, carries it into futurity ; and 
 a fourth carries it out of existence alto- 
 gether. Suppose, for instance, that I see 
 the sun rising out of the sea : I remember 
 to have seen him rise yesterday ; I believe 
 he will rise to-morrow near the same place ; 
 I can likewise imagine him rising in that 
 place, without any belief at all. Now, ac- 
 cording to this sceptical hypothesis, this 
 perception, this memory, this foreknow- 
 ledge, and this imagiuation, are all the same 
 idea, diversified only by difterent degrees of 
 vivacity. The perception of the sun rising 
 is the most lively idea ; the memory of his 
 rising yesterday is the same idea a little 
 more faint ; the belief of his rising to-mor- 
 row is the same idea yet fainter ; and the 
 imagination of his rising is still the same 
 idea, but faintest of all. One is apt to 
 think, that this idea might gradually pass 
 through all possible degrees of vivacity with- 
 out stirring out of its place. But, if we 
 think so, we deceive ourselves ; for no sooner 
 does it begin to grow languid than it moves 
 backward into time past. Supposing this 
 to be granted, we expect, at least, that, as 
 it moves backward by the decay of its 
 vivacity, the more that vivacity decays it 
 will go back the farther, until it ren^0V3 
 quite out of sight. But here we are de- 
 ceived again ; for there is a certain pe- 
 riod of this declining vivacity, when, as 
 if it had met an elastic obstacle in its mo- 
 tion backward, it suddenly rebounds from 
 the past to the future, without taking the 
 present in its way. And now, having got
 
 OF SEEING. 
 
 J 99 
 
 Into the regions of futurity, we are apt to 
 think that it has room enough to spend all 
 its remaining vigour : but still we are de- 
 ceived ; for, by another sprightly bound, it 
 mounts up into the airy region of imagina- 
 tion. So that ideas, in the gradual declen- 
 sion of their vivacity, seem to imitate the 
 inflection of verbs in grammar. They be- 
 gin with the present, and proceed in order 
 to the preterite, the future, and the inde- 
 finite. This article of the sceptical creed is 
 indeed so full of mystery, on whatever side 
 we view it, that they who hold that creed 
 are very injuriously charged with incre- 
 dulity ; for, to me, it appears to require as 
 much faith as that of St Athanasius. 
 
 However, we agree with the author of 
 the " Treatise of Human Nature," m this, 
 That our belief of the continuance of nature's 
 laws is not derived from reason. It is 
 an instinctive prescience of the operations 
 of nature, very like to that prescience of 
 human actions which makes us rely upon 
 the testimony of our fellow-creatures ; and 
 as, without the latter, we should be incapa- 
 ble of receiving information from men by 
 language, so, without the former, we should 
 be incapable of receiving the information of 
 nature by means of experience. 
 
 All our knowledge of nature beyond our 
 original perceptions, is got by experience, 
 and consists in the interpretation of natural 
 signs. The constancy of nature's laws 
 connects the sign with the thing signified ; 
 and, by the natural principle just now ex- 
 plained, we rely upon the continuance of 
 the connections which experience hath dis- 
 covered ; and thus the appearance of the 
 sign is followed by the belief of the thing 
 signified. 
 
 Upon this principle of our constitution, 
 not only acquired perception, but all induc- 
 tive reasoning, and all our reasoning from 
 analogy, is grounded ; and, therefore, for 
 want of another name, we shall beg leave 
 to call it the in'l active principle. It is from 
 the force of this principle that we imme- 
 diately assent to that axiom upon which all 
 our knowledge of nature is built, That 
 effects of the same kind must have the 
 same cause ; for effects and causes, in the 
 operations of nature, mean nothing but 
 signs and the things signified by them. Wc 
 perceive no projier causality or efficiency in 
 any natural cause ; but only a connection 
 established by the course of nature between 
 it and what is called its effect. Anteced- 
 ently to aU reasoning, we have, by our con- 
 stitution, an anticipation that there is a 
 fixed and steady course of nature : and we 
 have an eager desire to discover tliis course 
 of nature. We attend to every conjunction 
 of things which presents itself, and expect 
 the continuance of that conjunction. And, 
 when Hucli a conjunction has been often 
 
 observed, we conceive the things to be 
 naturally connected, and the appearance of 
 one, without any reasoning or reflection, 
 carries along with it the belief of the other. 
 
 If any reader should imagine that th« 
 inductive principle may be resolved into 
 what philosophers usually call the associ- 
 ation of ideas, let him observe, that, by 
 this principle, natural signs are not asso- 
 ciated with the idea only, but with the be- 
 lief of the things signified. Now, this can 
 with no propriety be called an association 
 of ideas, unless ideas and belief be one and 
 the same thing. A child has found the 
 prick of a pin conjoined with pain ; hence 
 he believes, and knows, that these things 
 are naturally connected ; he knows that the 
 one will always follow the other. If any 
 man will call this only an association of ideas, 
 I dispute not about words, but I think he 
 speaks very improperly. For, if we express 
 it in plain English, it is a prescience that 
 things which he hath found conjoined in 
 time past, will be conjoined in time to 
 come. And this prescience is not the effect 
 of reasoning, but of an original principle of 
 human nature, which I have called the 
 inductive principle.* 
 
 This principle, like that of credulity, is 
 unlimited in infancy, and gradually re- 
 strained and regulated as we grow up. It 
 leads us often into mistakes ; but is of in- 
 finite advantage upon tlie whole. By it, the 
 child once burnt shuns the fire ; by it, he 
 likewise runs away from the surgeon by 
 whom he was inoculated. It is better that 
 he sliould do the last, than that he should 
 not do the first. 
 
 But the mistakes we are led into by these 
 two natural principles, are of a dift'erent 
 kind. Men sometimes lead us into mis- 
 takes, when we perfectly understand their 
 language, by speaking lies. But Nature 
 never misleads us in this way : her lan- 
 guage is always true ; and it is only by 
 misinterpreting it that we fall into error. 
 There must be many accidental conjunc- 
 tions of things, as well as natural connec- 
 tions ; and the former are apt to be mis- 
 taken for the latter. Thus, in the instance 
 above mentioned, the child connected the 
 pain of inoculation with the surgeon ; 
 whereas it was really connected witii the 
 incision only. Philosophers, and men of 
 science, are not exempted from such mis- 
 takes ; indeed, all false reasoning in philo- 
 sophy is owing to tiieni ; it is drawn from 
 experience and analogy, as well as just rea- 
 soning, otherwise it could liave no verisimili- 
 tude ; but the one is an unskilful and rash.
 
 200 
 
 OF TilE HUMAN MIND. 
 
 the other a just and legitimate interpreta- 
 tion of natural signs. If a child, or a man 
 of common understanding, were put to 
 mterpret a book of science, written in his 
 mother-tongue, how many blunders and 
 mistakes would he be apt to fall into ? Yet 
 he knows as much of this language as is 
 necessary for his manner of life. 
 
 The language of Nature is the universal 
 study; and the students are of different 
 classes. Brutes, idiots, and children em- 
 ploy themselves in this study, and owe to it 
 all their acquired perceptions. Men of com- 
 mon understanding make a greater pro- 
 gress, and learn, by a small degree of 
 reflection, many things of which children 
 are ignorant. 
 
 Philosophers fill up the highest form in 
 this school, and are critics in the language 
 of nature. All tliese different classes have 
 one teacher — Experience, enlightened by 
 the inductive principle. Take away the 
 light of this inductive principle, and Ex- 
 perience is as blind as a mole : she may, 
 indeed, feel what is present, and what im- 
 mediately touches her ; but she sees nothing 
 that is either before or behind, upon the 
 right hand or upon the left, future or past. 
 
 The rules of inductive reasoning, or of a 
 just interpretation of Nature, as well as the 
 fallacies by which we are apt to misinter- 
 pret her language, have been, with wonder- 
 ful sagacity, delineated by the great genius 
 of Lord Bacon : so that his " Novum 
 Crganiini''' may justly be called " A Gram- 
 mar of the Language of Nature." It adds 
 greatly to the merit of this work, and atones 
 for its defects, that, at the time it was 
 written, the world had not seen any tole- 
 rable model of inductive reasoning,* from 
 which the rules of it might be copied. The 
 arts of poetry and eloquence were grown up 
 to perfection when Aristotle described them ; 
 but the art of interpreting Nature was 
 yet in emhrijo when Bacon delineated its 
 manly features and proportions. Aristotle 
 drew his rules from the best models of 
 those arts that have yet appeared ; but the 
 best models of inductive reasoning that 
 have yet appeared, which I take to be the 
 third book of the " Principia," and the 
 " Optics," of Newton, were drawn from 
 Bacon's rules. Tiie purpose of all those 
 rules, is to teach us to distinguish seeming 
 or apparent connections of things, in the 
 course of nature, from such as are real. 
 
 They that are unskilful in inductive 
 reasoning, are more apt to fall into error 
 in their reasonings from the phsenomena of 
 nature than in their acquired perceptions ; 
 because we often reason from a few in- 
 stances, and thereby are apt to mistake acci- 
 dental conjunctions of things for natural 
 
 « Yet Galileo was antcrinr to Bacon. — H. 
 
 connections : but that habit of passing, 
 without reasoning, from the sign to the 
 thmg signified, which constitutes acquired 
 perception, must be learned by many in- 
 stances or experiments ; and the number of 
 experiments serves to disjoin those things 
 which have been accidentally conjoined, 
 as well as to confirm our belief of natural 
 connections. 
 
 From the time that children begin to use 
 their hands. Nature directs them to handle 
 everything over and over, to look at it 
 while they handle it, and to put it in va- 
 rious positions, and at various distances 
 from the eye. We are apt to excuse this 
 as a childish diversion, because they must 
 be doing something, and have not reason 
 to entertain themselves in a more manly 
 way. But, if we think more justly, we 
 shall find, that they are engaged in the 
 most serious and important study ; and, if 
 they had all the reason of a philosopher, 
 they could not be more properly employed. 
 For it is this childish employment that 
 enables them to make the proper use of 
 their eyes. They are thereby every day 
 acquiring habits of perception, which are 
 of greater importance than anything we 
 can teach them. The original perceptions 
 which Nature gave them are few, and in- 
 sufficient for the purposes of life ; and, 
 therefore, she made them capable of ac- 
 quiring many more perceptions by habit. 
 And, to complete her work, she hath given 
 them an unwearied assiduity in applying to 
 the exercises by which those perceptions are 
 acquired. 
 
 This is the education which Nature gives 
 to her children. And, since we have fallen 
 upon this subject, we may add, that another 
 part of Nature's education is, That, by the 
 course of things, children must often exert 
 all their muscular force, and employ all 
 their ingenuity, in order to gratify their 
 curiosity, and satisfy their little appetites. 
 What they desire is only to be obtained 
 at the expense of labour and patience, and 
 many disappointments. By the exercise 
 of body and mind necessary for satisfying 
 their desires, they acquire agility, strength, 
 and dexterity in their motions, as well as 
 health and vigour to their constitutions ; 
 they learn patience and perseverance ; 
 they learn to bear pain without dejection, 
 and disappointment without despondence. 
 The education of Nature is most perfect in 
 savages, who have no other tutor ; and we 
 see that, in the quickness of all their senses, 
 in the agility of their motions, in the hardi- 
 ness of their constitutions, and in the 
 strength of their minds to bear hunger, 
 thirst, pain, and disappointment, they com- 
 monly far exceed the civilized. A most 
 ingenious writer, on this account, seems to 
 prefer the savage life to that of society. 
 
 i
 
 CONCLUSION. 
 
 201 
 
 But the education of Nature could never 
 of itself prcHluce a Rousseau. It is the 
 intention of Nature that human educa- 
 tion should be joined to her institution, in 
 order to form the man. And she hath 
 fitted us for human education, by the natural 
 principles of imitation and credulity, which 
 discover themselves almost in infancy, as 
 well as by others which are of later growth. 
 
 A\'hen the education which we receive 
 from men, does not give scope to the educa- 
 tion of Nature, it is wrong directed ; it tends 
 to hurt our faculties of perception, and to 
 enervate both the body and mind. Nature 
 hath her way of rearing men, as she hath 
 of curing their diseases. The art of medi- 
 cine is to follow Nature, to imitate and to 
 assist her in the cure of diseases ; and the 
 art of education is to follow Nature, to 
 assist and to imitate her in her way of 
 rearing men. The ancient iirfiabitants of 
 the Baleares followed Nature in the man- 
 ner of teaching their children to be good 
 archers, wlien they hung their dinner aloft 
 by a thread, and left the younkers to bring 
 it down by their skill in archery. 
 
 The education of Nature, without any 
 more human care than is necessary to pre- 
 serve life, makes a perfect savage. Human 
 education, joined to that of Nature, may 
 make a good citizen, a skilful artisan, or a 
 well-bred man • but reason and reflection 
 must superadd their tutory, in order to 
 produce a Rousseau, a Bacon, or a Newton. 
 
 Notwithstanding the innumerable errors 
 committed in Imman education, there is 
 hardly any education so bad as to be worse 
 than none. And I apprehend that, if even 
 Rousseau were to choose whether to educate 
 a son among the French, the Italians, the 
 Chinese, or among the Eskimaux, he would 
 not give the preference to the last. 
 
 When Reason is properly employed, she 
 will confirm the documents of Nature, which 
 are always true and wholesome ; she will 
 distinguish, in the documents of human 
 education, the good from the bad, rejecting 
 the last with modesty, and adhering to the 
 first with reverence. 
 
 Jlost men continue all their days to be 
 just what Nature and human education 
 made them. Their manners, their o])inions, 
 their virtues, and their vices, are all got by 
 lial/it, imitation, and instruction ; and rea- 
 son has little or no share in forming them. 
 
 CHAPTER VII. 
 
 Conclusion. 
 
 CONTAlNINi; RKFJ,E(:TIf)NS UPON TlIK oriNIONS 
 OF I'lllI.OSul-llKKS ON THIS Slli.IW T. 
 
 TiiKHF, are two wnvs in which men iiiav 
 
 form their notions and opinions concerning 
 the mind, and concernuig its powers and oper- 
 ations. The first is the only way that leads 
 to truth ; but it is narrow and rugged, and 
 few have entered upon it. The second is 
 broad and smooth, and hath been much 
 beaten, not only by the vulgar, but even by 
 }ihilosophers ; it is sufficient for conunon 
 life, and is well adapted to the purposes of the 
 poet and orator : but, in philosophical dis- 
 quisitions concerning the mind, it leads to 
 error and delusion. 
 
 We may call the first of these ways, the 
 ivay of reflection. When the operations of ' 
 the mind are exerted, we are conscious of 
 them ; and it is in our power to attend to 
 them, and to reflect upon them, until they 
 become familiar objects of thought. This 
 is the only way in which we can form just 
 and accurate notions of those operations. 
 But this attention and reflection is so diffi- 
 cult to man, surrounded on all hands by 
 external objects which constantly solicit his 
 attention, that it has been very little prac- 
 tised, even by philosophers. In the course 
 of this inquiry, we liave had many occa- 
 sions to shew how little attention hath been 
 given to the most familiar operations of the 
 senses. 
 
 The second, and the most common way, 
 in which men form their opinions concern- 
 ing the mind and its operations, we may 
 call llie way of analogy. There is nothing 
 in the course of nature so singular, but we 
 can find some resemblance, or at least some 
 analogy, between it and other things with 
 which we are acquainted. The mind na- 
 turally delights hi hunting after such analo- 
 gies, and attends to them with pleasure. 
 From them, poetry and wit derive a great 
 part of their charms ; and eloquence, not a 
 little of its jtersuasive force. 
 
 Besides tlie pleasure we receive from 
 analogies, they are of very considerable use, 
 both to facilitate the conception of things, 
 when they are not easily apprehended with- 
 out such a handle, and to lead us to probable 
 conjectures about their iKiture and qualities, 
 when we want the melius of more direct 
 and innncdiate knowledge. When I con- 
 sider that the planet .lupiter, in like manner 
 as the earth, rolls round his own axis, and 
 revolves round the sun, and that he is on- 
 lightened by several secondary ]il:iiicts, as 
 tlie earth is enlightened by the moon, I am 
 apt to conjecture, from analogy, tliat, as the 
 earth by these means is fitted to be the 
 habitation of various orders of animals, so 
 the planet .lupiter is, by the like means, 
 fitted lor the same puriioso : and, having no 
 argument more direct and conclusive to ile- 
 teniiine me in this ])oiiit, I yield, to this 
 analogical reasoning, a degree of assent 
 jiroportioncd to its strength. Wlien I 
 ojiscrvc that the jiotato plant very nuuli
 
 202 
 
 OF THE HUMAN MIND. 
 
 resembles the solanum in its flower and 
 fructification, and am informed that the 
 last is poisonous, I am apt from analogy 
 to have some suspicion of the former : but, 
 in this case, I have access to more direct 
 and certain evidence ; and, therefore, ought 
 not to trust to analogy, which would lead 
 me into an error. 
 
 Arguments from analogy are always at 
 hand, and grow up spontaneously in a 
 fruitful imagination ; while arguments that 
 are more direct and more conclusive 
 often require painful attention and appli- 
 cation : and therefore mankind in gene- 
 ral have been very much disposed to trust 
 to the former. If one attentively examines 
 the systems of the ancient philosophers, 
 either concerning the material world, or 
 concerning the mind, he will find them to 
 be built solely upon the foundation of ana- 
 logy. Lord Bacon first delineated the 
 strict and severe method of induction ; since 
 his time, it has been applied with very happy 
 success in some parts of natural philosophy — 
 and hardly in anything else. But there is 
 no subject in which mankind are so much 
 disposed to trust to the analogical way of 
 thinking and reasoning, as in what concerns 
 the mind and its operations ; because, to 
 form clear and distinct notions of those 
 operations in the direct and proper way, 
 and to reason about them, requires a habit 
 of attentive reflection, of which few are 
 capable, and which, even by those few, 
 cannot be attained without much pains and 
 labour. 
 
 Every man is apt to form his notions of 
 things difficult to be apprehended, or less 
 familiar, from their analogy to things which 
 are more familiar. Thus, if a man bred to 
 the seafaring life, and accustomed to think 
 and talk only of matters relating to naviga- 
 tion, enters into discourse upon any other 
 subject, it is well known that the language 
 and the notions proper to his own profes- 
 sion are infused into every subject, and all 
 things are measured by the rules of naviga- 
 tion ; and, if he should take it into his head 
 to philosophize concerning the faculties of 
 the mind, it cannot be doubted but he would 
 draw his notions from the fabric of his ship, 
 and would find in the mind, sails, masts, 
 rudder, and compass." 
 
 Sensible objects, of one kind or other, do 
 no less occupy and engross the rest of man- 
 kind, than things relating to navigation the 
 seafaring man. For a considerable part of 
 life, we can think of nothing but the objects 
 of sense ; and, to attend to objects of an- 
 other nature, so as to form clear and dis- 
 tinct notions of them, is no easy matter, 
 even after we come to years of reflection. 
 
 » See " Essays on the Intellectual Powers," Ess. 
 VI., ch. viii., Nos, 2 and 6.— H. 
 
 The condition of mankind, therefore, affords 
 good reason to apprehend that their lan- 
 guage, and their common notions concern- 
 ing the mind and its operations, will be ana- 
 logical, and derived from the objects ol 
 sense ; and that these analogies wUl be apt 
 to impose upon philosophers, as well as 
 upon the vulgar, and to lead them to ma- 
 terialize the mind and its faculties : and 
 experience abundantly confirms the truth 
 of this. 
 
 How generally men of all nations, and in 
 all ages of the world, have conceived the 
 soul, or thinking principle in man, to be 
 some subtile matter, like breath or wind, 
 the names given to it almost in all languages 
 sufficiently testify. * We have words which 
 are proper, and not analogical, to express 
 the various ways in which we perceive ex- 
 ternal objects by the senses — such as feel- 
 ing, sight, taste ; but we are often obliged 
 to use these words analogically, to express 
 other powers of the mind which are of a 
 very different nature. And the powers 
 which imply some degree of reflection, have 
 generally no names but such as are analo- 
 gical. The objects of thought are said to 
 be in the mind — to be apprehended, com- 
 prehended, conceived, imagined, retained, 
 weighed, ruminated.* 
 
 It does not appear that the notions of 
 the ancient philosophers, with regard to the 
 nature of the soul, were much more re- 
 fined than those of the vulgar, or that they 
 were formed in any other way. We shall 
 distinguish the philosophy that regards our 
 subject into the old and the 7iew. The old 
 reached down to Des Cartes, who gave it a 
 fatal blow, of which it has been gradually 
 expiring ever since, and is now almost ex- 
 tinct. Des Cartes is the father of the new 
 philosophy that relates to this subject ; but 
 it hath been gradually improving since his 
 time, upon the principles laid down by him. 
 The old philosophy seems to have been 
 purely analogical ; the new is more derived 
 from reflection, but stUl with a very con- 
 siderable mixture of the old analogical no- 
 tions. 
 
 Because the objects of sense consist of 
 matter and form, the ancient philosophers 
 conceived everything to belong to one of 
 these, or to be made up of both. Some, 
 therefore, thought that the soul is a parti- 
 cular kind of subtile matter, separable from 
 our gross bodies ; others thought that it is 
 only a particular form of the body, and in- 
 separable from it. •]- For there seem to have 
 
 • The examples that might be given of these, 
 would, I find, exceed the limits of a foot-note. — H. 
 
 t It would, however, be a very erroneous assump. 
 tion to hold, that those who viewed the soul as a form 
 inseparable from the body, denied the existence, a d 
 the independent existence, of any mental principle 
 after the dissolution of i he material oiganism. Thus, 
 Aristotle defines the soul, the Form or Entelechy of an
 
 CONCLUSIOX. 
 
 203 
 
 been some among the ancients, as well as 
 among the moderns, who conceived that a 
 certain structure or organization of the 
 body, is all that is necessary to render 
 it sensible and intelligent." The different 
 powers of the mind were, accordingly, by 
 the last sect of philosophers, conceived to 
 belong to different parts of the body — as the 
 heart, the brain, the Uver, the stomach, the 
 blood, t 
 
 They who thought that the soul is a sub- 
 tile matter, separable from the body, dis- 
 puted to which of the four elements it be- 
 longs — whether to earth, water, air, oyfire. 
 Of the three last, each had its particular 
 advocates.:!: But some were of opinion, 
 that it partakes of all the elements ; that it 
 must have something in its composition 
 similar to everything we perceive ; and 
 that we perceive earth by the earthly part ; 
 water, by the watery part ; and fire, by 
 the fiery part of the soul.§ Some philoso- 
 phers, not satisfied with determining of 
 what kind of matter the soul is made, in- 
 quired likewise into its figure, which tliey 
 determined to be spherical, that it might 
 be the more fit for motion. || The most 
 spiritual and sublime notion concerning the 
 nature of the soul, to be met with among 
 the ancient philosophers, I conceive to be 
 that of the Platonists, who held that it is 
 made of that celestial and incorruptible 
 matter of which the fixed stars were made, 
 and, therefore, has a natural tendency to 
 rejoin its proper element.^ I am at a loss 
 
 organized body; and yet he, hypotlietically at lea-t, 
 admits that N»f, or Intelligenc ■, i»adventitiousto this 
 animated orgai)ism,.and, therefore, possibly, and even 
 probably, separable from it, and immortal. J'he term 
 ioa/ in this Instance is not adequate to the Intellec 
 tual Ego.— H. 
 * Thus Parmenides: — 
 
 'Cls yoif ixifu Ix'i x^ci<ri; /j,iXiiuv rroXurXayx- 
 
 ruvt 
 To/; voo? avO^uiTotff"! ^aois'ViXiv' to yv-^ cc-to 
 
 So likewise Dicaearehus, (ialen, and other*.— H. 
 
 t This- is altogether erroneous. Those pinloso. 
 phers who assigned ^liHercnt -scats or organs (or dif- 
 ferent parts or funciionsof the soul, did not therefore 
 admit the absolute dependence of the soul upon the 
 body. For instance, the Pyhagoreans and the I'la- 
 tonisis. — il. 
 
 X Aristotle observes that earlh was the only ele- 
 ment which had found no advocate. This he means 
 only of earth by itsc(f—t'oT, in combination with otic 
 or'more of the others, it was by in.itiy philosophers 
 allowed to be atconstituent of soul. Of these last, 
 water had its champion in Hippo ; air, in Aiiaxi- 
 mene'S and Diogenes, with whom are sometimes 
 enumerated Anaxim^inder, .\naxagoras, Archelaus, 
 jEiiesidemus, Ac. ; Jinr, in Democriius and Lcucip. 
 pus, peihaps in Hipparchus and Heraclitus — 11. 
 
 § Empedocles; and I'lato, as interpreted by Aris- 
 totle — H. 
 
 II Uemocritus and Lcucippus held the soul, as 
 an igneous principle, to consibt of spherical atoms. 
 ^H. 
 
 5 See the " Timajus" of Plato. Plotinus, and 
 the lower Platonists in general, held the- human f-oul 
 to be an emanation from the Atitma Mmidi. Aristo- 
 tle seems to have favoureil an opinion correspondent 
 to Plato's Even the nentieiit or animal soul, in. 
 separable a< it ii from bo<lyj he maiiit. lined to be 
 
 to say, in which of these classes of philoso- 
 phers Aristotle ought to be placed.* He 
 defines the soul to be. The first \vriXixi'» 
 of a natural body which has potential life. 
 I beg to be excused from translating the 
 Greek word, because I know not the mean- 
 ing of it.-f-J 
 
 The notions of the ancient philosophers 
 with regard to the operations of the mind, 
 particularly with regard to perception and 
 ideas, seem likewise to have been formed 
 by the same kind of analogy. 
 
 Plato, of the writers that are extant, 
 first introduced the word idea into philoso- 
 phy ; but his doctrine upon this subject 
 had somewhat peculiar. He agreed with 
 the rest of the ancient philosophers in this — 
 that all things consist of matter and form ; 
 and that the matter of which all things 
 were made, existed from eternity, without 
 
 higher than any sublunary element, and supposed it 
 to be " analogous to the element of the stars." — De 
 Generalwne Animalium, L. II., c. 2. — H. 
 
 * '1 his is the former of the two definitions which 
 Aristotle gives of the human soul, in the .second 
 book of his treatise, " Utei ■\,vxrii" In the latter, he 
 defines it a posteriori from ilsphanomena — that by 
 which we live, feel or perceive, [^will,^ move, and 
 understand : — a definition which has been generally 
 adopted by philosophers, .md, though morecoinplete, 
 is in substance that of Reid himself. "A'// the j/iind 
 of a man," (says Keid,) " we understand that in hint 
 which thinks, remembers, reasons, wilts."— EsfiWri 
 ON THE Intellectual Powers, Essay I., chap. i. 
 ^H. 
 
 + Though Cicero misapprehended, and Hermo. 
 laus Barbarus raised the lievil to expound it, this 
 Aristotelic term is by no means of a very arduous in. 
 terpretation. It is not, however, here the place to 
 explain the contents of ihis celebrated definition.— 
 H. 
 
 X " For her [; he soul's] true form how can my spark 
 discern. 
 Which, dim by nature, art did never clear? 
 
 When the great wits, of whom all skill we learn. 
 Are ignorant both what she is, and where. 
 
 " One thinks the soul is air ; another, fire; 
 
 Ani'ther, blood, dilfUs'd about the heart ; 
 Another saith, the elements conspire, 
 
 And to her essence each dolh lend a part. 
 
 •• Musicians think our souls are harmonics ; 
 
 Physicians hold that they complexions he; 
 Epicures malie them swarms of atomies. 
 
 Which do by chance into our bodies flee. 
 
 " Some think one gcn'ral soul fills every brain. 
 As the bright sun sheds light In every star; 
 
 While others think the name of soul is vain. 
 And that we only well-mixt bodies are. 
 
 " In judgment of her substance as they vary, 
 So vary they in judgment of her seat ; 
 
 For some her chair up to the brain do carry. 
 Some thrust it down into the stomach's heat. 
 
 " Some place it in the root of life, the heait; 
 
 Some in the liver fountain of the veins; 
 Some say, she's nil in all, and all in ev'ry part; 
 
 Some that she's not coiitain'd, but all contains. 
 
 " Thus these great rlerks I lit little wisdom shew. 
 While with- their doitrine^ they at hazard play; 
 
 'Tossing their light opinions to and fio, 
 'J'o mock the lewd, as learn'd in this as they. 
 
 " For no cra/'d hrain could ever yet propound, 
 
 'J'oui liiiig the soni, so taiii and fonil a Ihouglil, 
 But some moiig these masters have been foiiml. 
 Which, in their schools, tlicself-sanie thing havf 
 taught." 
 
 Sill .lolls Davh K II.
 
 204 
 
 OF THE HUMAN MIND. 
 
 form : but he lilcewise believed that there 
 are eternal forms of all possible things 
 which exist, without matter ; and to these 
 eternal and immaterial forms he gave tiie 
 name of iileas ; maintaining that they are 
 the only object of true knowledge. It is of 
 no great moment to us, whether he bor- 
 rowed these notions from Parmenides, or 
 whether they were the issue of his own 
 creative imagination. The latter Platonists 
 seem to have improved upon them, in con- 
 ceiving those ideas, or eternal forms of things, 
 to exist, not of themselves, but in the di- 
 vine mind,* and to be the models and pat- 
 terns according to which all things were 
 made : — 
 
 " Then llv'd the Eternal One ; then, deep retir'd 
 In his unf'athom'd essence, view'd at large 
 7 he uncreated images of things." 
 
 To these Platonic notions, that of Male- 
 branche is very nearly allied. This author 
 seems, more than any other, to have been 
 aware of the difficulties attending the com- 
 mon hypothesis concerning ideas-f- — to wit. 
 That ideas of all objects of thought are in 
 the human mind ; and, therefore, in order 
 to avoid those difficulties, makes the ideas 
 which arc the immediate objects of human 
 thought, to be the ideas of things in the 
 Divine mind, who, being intimately present 
 to every human mind, may discover his 
 ideas to it, as far as pleaseth him. 
 
 The Platonists and Malebranche ex- 
 cepted, J all other philosophers, as far as I 
 know, have conceived that there are ideas or 
 images of every object of thought in the 
 human mind, or, at least, in some part of 
 the brain, where the mind is supposed to 
 have its residence. 
 
 Aristotle had no good affection to the 
 word idea, and seldom or never uses it but 
 
 • Whether Plato viewed Ideas as existences in- 
 liependent of the divine mind, is a contested point ; 
 though, upon the whole, it appears more probable 
 that he did not. It is, however, admit'ed, on all 
 hands, to be his doctrine, that Ideas were I he patterns 
 according towhich the Deiiy fashioned the phsenome- 
 nalorcctypal world. — H. 
 
 t It should be carefully observed that the term 
 Idea, previous to the time of l)es Cartes, was used 
 exclusively, or all but exclusively, in its Platonic 
 significatioTi. By Des Cartes, and other contem- 
 porary philosophers, it was first extended to denote 
 our representations in general. Many curious 
 blunders have arisen in consequence of an ignorance 
 of this. I may notice, liy the way, that a confusion 
 of ideas in the Platonic with ideas in the Cartesian 
 sense has here led Kcid into the error of assimilating 
 the hypothesis of Plato and the hypothesisof Male- 
 branc e in regard to our vision in the divine mind. 
 The Platonic theory of Perception, in fact, bears a 
 closer analogy to the t artesian and Leibniizian doc- 
 trines than lothat of Malebranche. See notes on tlie 
 "Essays on the Intellectual Powers." Ess. II., ch. 
 iv. or vi'., and Note (4. — H. 
 
 t The I'kitonistsare no exception ; for they allowed 
 the human iniiid to have potentially within it the 
 forms or lepresentat ons for all possible objects of per- 
 ception ;each representation being, by the spontaneity 
 of mind itself, elicited into c nsciouncss on occasion 
 of its corresponding olijcct coming within the sphere 
 of sense. Bi<t of this again.— H . 
 
 in refuting Plato's notions about ideas. He 
 thought that matter may exist without form ; 
 but that forms cannot exist without matter. 
 But, at the same time, he taught, That 
 there can be no sensation, no imagination, 
 nor intellection, without forms, phantasms, 
 or species in the mind ; and that things 
 sensible are perceived by sensible species, 
 and things intelligible by intelligible 
 species.* His followers taught, more ex- 
 plicitly, that those sensible and intelligible 
 species are sent forth by the objects, and 
 make their impressions upon the passive 
 intellect ; and that the active intellect per- 
 ceives them in the passive intellect. And 
 this seems to have been the common opinion 
 while the Peripatetic philosophy retained 
 its authority. 
 
 The Epicurean doctrine, as exphiined by 
 Lucretius, though widely different from the 
 Peripatetic in many things, is almost the 
 same in this. He affirms, that slender 
 films or ghosts {teiiuia rerum simn/acra) are 
 still going off from all things, and flying 
 about ; and that these, being extremely 
 subtile, easily penetrate our gross bodies, 
 and, striking upon the mind, cause thought 
 and imagination. -f 
 
 After the Peripatetic system had reigned 
 above a thousand years in the schools of 
 Europe, almost without a rival, it sunk be- 
 fore that of Des Cartes ; the perspicuity 
 of whose writings and notions, contrasted 
 with the obscurity of Aristotle and his com- 
 mentators, created a strong prejudice in 
 favour of this new philosophy. The cha- 
 racteristic of Plato's genius was sublimity, 
 that of Aristotle's, subtilty ; but Des Cartes 
 far excelled both in perspicuity, and be- 
 queathed this spirit to his successors. The 
 system which is now generally received, 
 with regard to the mind and its operations, 
 derives not only its spirit from Des Cartes, 
 but its fundamental principles ; and, after all 
 the improvements made by Malebranche, 
 Locke, Berkeley, and Hume, may still be 
 called I'le Cartedcui sysieni : we shall, there- 
 fore, make some remar]<s upon its spirit 
 and tendency in general, and upon its doc- 
 trine concerning ideas in particular. 
 
 1. It may be observed. That the method 
 which Des Cartes pursued, naturally led 
 him to attend more to the operations of the 
 mind by accurate reflection, and to trust 
 less to analogical reasoning upon this sub- 
 
 • The doctrine of Aristotle on this subject, admits 
 of an interpretation far more philosophical than that 
 given to it by most of his followers. But of this 
 again. — H. 
 
 -f- The uTOffoiKi, iiou>M tCxoi, &c. of Demo, 
 critus and Epicurus differed from the uhrj, or species 
 of the later I'eripatetic', in this — that the former 
 were confessedly substantive and corporeal, while 
 the latter, as mere accidents, shrewdly puzzled their 
 advocates, to say how they were separcble from a 
 subjert, and whether they were material, immaterial, 
 or soniel.ow nitcrmediate between body and snirii 
 — H.
 
 CONCLUSION. 
 
 205 
 
 ject, than aiiv philosopher had done before 
 him. Intending to build a system upon a 
 new foundation, he began with a resolution 
 to admit nothing but what was abso- 
 lutely certain and evident. He supposed 
 that his senses, his memory, his reason, 
 and every other faculty to which we trust 
 in common life, might be fallacious ; and 
 resolved to disbelieve everything, until he 
 was compelled by irresistible evidence to 
 yield assent. 
 
 In this method of proceeding, what ap- 
 peared to him, first of all, certain and 
 evident, was, That he thought — that he 
 doubted — that he deliberated. In a word, 
 the operations of his own mind, of which 
 he was conscious, must be real, and no de- 
 lusion ; and, though all his other faculties 
 should deceive him, his consciousness could 
 not.* This, therefore, he looked upon as 
 the first of all truths. This was the first 
 firm ground upon which he set his foot, 
 after being tossed in the ocean of scepticism ; 
 and he resolved to build all knowledge up- 
 on it, without seeking after any more first 
 principles. 
 
 As every other truth, therefore, and par- 
 ticularly the existence of the objects of 
 sense, was to be deduced by a train of strict 
 argumentation from what he knew by con- 
 sciousness, he was naturally led to give 
 attention to the operations of which he was 
 conscious, without borrowing his notions of 
 them from external things. 
 
 It was not in the way of analogy, but 
 of attentive reflection, that he was led to 
 observe. That thought, volition, remem- 
 brance, and the other attributes of the 
 mind, are altogether unlike to extension, 
 to figure, and to all the attributes of body ; 
 that we have no reason, there'bre, to con- 
 ceive thinking substances to have any re- 
 semblance to extended substances ; and 
 that, as the attributes of the thinldng sul)- 
 stance are things of which we are coiiscious, 
 we may have a more certain and immediate 
 knowledge of them by reflection, than we 
 can have of external objects by our senses. 
 
 These observations, as far as I know, 
 were first made by Des Cartes ; and they 
 are of more importance, and throw more 
 light upon the subject, than all that had 
 been said uj)r)n it before. They ought to 
 make us diffident and jealous of every 
 notion concerning the mind and its oper- 
 ations, which is drawn from sensible ob- 
 jects in the way of analogy, and to inaki^ 
 us rely only upon aocurate reflection, as 
 the source of all real knowledge upon this 
 subject. 
 
 2. I observe that, as the Peripatetic 
 
 ♦ DcM Cartes did not rommit Hcid'g error of mak- j 
 iiig con:)CiouMies» a cii-orilii:atf and .'.prcijl laciilly. I 
 
 system has a tendency to materialize the 
 mind and its operations, so the Cartesian 
 has a tendency to spiritualize body and its 
 qualities. One error, common to both 
 s\ stems, leads to the first of these extremes 
 in the way of analogy, and to tlie last in 
 the way of reflection. The error I mean 
 is. That we can know nothing about body, 
 or its qualities, but as far as we have sens- 
 ations which resemble those qualities. Both 
 systems agreed in this : but, according to 
 their difl'erent methods of reasoning, they 
 drew very different conclusions from it ; the 
 Peripatetic drawing his notions of sensa- 
 tion from the qualities of body ; the Car- 
 tesian, on the contrary, drawing his notions 
 of the qualities of body from his sensa- 
 tions. 
 
 The Peripatetic, taking it for granted 
 that bodies and their qualities do really 
 exist, and are such as we commonly take 
 them to be, inferred from them the nature 
 of his sensations, and reasoned in this man- 
 ner : — Our sensiitions are the impressions 
 which t-eiisibie objects make upon the mind, 
 and may be comjiared to the impression of 
 a seal upon wax : the impression is the 
 image or form of the seal, without the mat- 
 ter of it ; in like manner, every sensation 
 is the image or form of some sensible qua- 
 lity of the object. This is the reasoning of 
 Aristotle : and it has an evident tendency 
 to materialize the mind and its sensations. 
 The Cartesian, on the contrary, thinks 
 that the existence of body, or of any of 
 its qualities, is not to be taken as a first 
 principle ; and that we ought to admit no- 
 thing concerning it, but what, by just rea- 
 soning, can be deduced from our sensatioiis ; 
 and he knows that, by reflection, we can 
 form clear and distinct notions of our sensa- 
 tions, without borrowing our notions of 
 them by analogy from the objects of sense. 
 The Cartesians, therefore, beginmng to give 
 attention to their sensations, first discovered 
 that the sensations corresponding to second- 
 ary qualities, cannot resemble aiiy quality 
 of body. Hence, Des Cartes and Locke 
 inferred, that sound, taste, smell, colour, 
 heat, and cold, which the vulgar took to 
 be (jualitics of body, were not (pialities of 
 body, but mere sensations of tlie mind." 
 
 * Dc8 Cartes and Locke made no such inference. 
 'J'hey only maintained (as Kcid himself states) that 
 found, taste, Ac, as sensations in us, have no re- 
 semblance to any quahty in bodies. If the nanvs, 
 therefore, ol sound, taste, Ac, were to l)e emiiloyrd 
 univocally — i. c, to denote always tliingMthe same or 
 similar — in that ca^ethcy ar(;ued that these terin«, if 
 properly eigi ificant of the seiifalions, cciu'd not be 
 properly apiiliiil to the rdativi' (inalities in external 
 things, 'this is distinctly stated biilh liy ' es Carles 
 and I.ocke. Hut I'es Cartes anil the Cartesians (jI). 
 •erve thit the terms in (|ue^tion are i (|iMv<ji'idly 
 used; bciiiK tonimonly applied both to that in thiiKi 
 winch occasions the sensation in us, and to that 
 sens, ition itself. Niiy, th i artciiaiis, to avoid the 
 anibi|4Uity, uis'ihgtiiiih' d tlie lwi< r< lalivis by ililler.
 
 206 
 
 OF THE HUMAN MIND. 
 
 Afterwards, the ingenious Berkeley, con- 
 sidering more attentively the nature of sens- 
 ation in general, discovered and demon- 
 strated, tiiat no sensation whatever could 
 possibly resemble any quality of an insen- 
 tient being, such as body is supposed to be ; 
 and hence he inferred, very justly, that 
 there is the same reason to hold extension, 
 figure, and all the primary qualities, to be 
 mere sensations, as there is to hold the 
 secondary qualities to be mere sensations. 
 Thus, by just reasoning upon the Cartesian 
 principles, matter was stripped of all its 
 qualities ; the new system, by a kind of me- 
 taphysical sublimation, converted all the qua- 
 lities of matter into sensations, and spiritu- 
 alized body, as the old had materialized 
 spirit. 
 
 The way to avoid both these extremes, is 
 to admit the existence of what we see and 
 feel as a first principle, as well as the exist- 
 ence of things whereof we are conscious ; 
 and to take our notions of the qualities of 
 body, from the testimony of our senses, 
 with the Peripatetics ; and our notions of 
 our sensations, from the testimony of con- 
 sciousness, with the Cartesians. 
 
 3, I observe, That the modern scepticism 
 is the natural issue of the new system ; and 
 that, although it did not bring forth this 
 monster until the year 1739,* it may be 
 said to have carried it in its womb from 
 the beginning. 
 
 The old system admitted all the princi- 
 ples of common sense as first principles, 
 without requiring any proof of them ; and, 
 therefore, though its reasoning was com- 
 monly vague, analogical, and dark, yet it 
 was built upon a broad foundation, and had 
 no tendency to scepticism. We do not 
 find that any Peripatetic thought it incum- 
 bent upon him to prove the existence of a 
 material world ;t but every writer upon 
 the Cartesian system attempted this, until 
 Berkeley clearly demonstrated the futility 
 of their arguments ; and thence concluded 
 
 ent names. To take colour, for example; they 
 called colour, aa a sens; tiou in the mind, formal 
 colour ; colour, as a fiuality in bodies capable of 
 producing the sensation, primitive or radical ctAour. 
 They had likewise another distinction of less iral 
 portance— that of seconda-y or derivative colour ; 
 meaning thereby that which the coloured bodies 
 impress upon the external medium I hus, again, 
 primitive or radical sound was the property of a body 
 to determine a certain agitation in the air ot other 
 medium ; seco- dary or derivative sound, that agita- 
 tion in the medium itself; formal sound, the sensa- 
 tion occasioned by the impression made by the radical 
 sound mediately, and by the derivative immediately, 
 upon the organ of hearing. There is thus no dif. 
 terence between Rfid and the Cartesians, except 
 that the doctrine which he censures is in fact more 
 precise and explicit than his own.— H. 
 
 • When Humes "Treatise of Human Nature" 
 ippeared— H. 
 
 f 'I'his is not correct ; but the reason why Idealism 
 did not prevail in the schools of the middle ages is 
 one, as it appears to me, merely theological. Hut on 
 this curious Question I canno now touch.— H. 
 
 that there was no such thing as a material 
 world ; and that the belief of it ought to be 
 rejected as a vulgar error. 
 
 The new system admits only one of the 
 principles of conmion sense as a first prin- 
 ciple ; and pretends, by strict argumenta- 
 tion, to deduce all the rest from it. That 
 our thoughts, our sensations, and every 
 thing of which we are conscious, hath a 
 real existence, is admitted in this system 
 as a first principle ; but everything else 
 nmst be made evident by the light of rea- 
 son. Reason must rear the whole fabric of 
 knowledge upon this single principle of 
 consciousness. 
 
 There is a disposition in human nature 
 to reduce things to as few principles as 
 possible ;" and this, without doubt, adds to 
 the beauty of a system, if the principles 
 are able to support what rests upon them. 
 The mathematicians glory, very justly, in 
 having raised so noble and magnificent a 
 system of science, upon the foundation of 
 a few axioms and definitions. This love 
 of simplicity, and of reducing things to few 
 principles, hath produced many a false 
 system ; but there never was any system 
 in which it appears so remarkably as that 
 of Des Cartes.* His whole system con- 
 cerning matter and spirit is built upon 
 one axiom, expressed in one word, cogito. 
 Upon the foundation of conscious thought, 
 with ideas for his materials, he builds his 
 system of the human understanding, and 
 attempts to account for all its phoenomena : 
 and having, as he imagined, from his con- 
 sciousness, proved the existence of matter ; 
 upon the existence of matter, and of a cer- 
 tain quantity of motion originally impressed 
 upon it, he builds his .system of the material 
 world, and attempts to account for all its 
 phenomena. 
 
 These principles, with regard to the ma- 
 terial system, have been found insufficient ; 
 and it has been made evident that, besides 
 matter and motion, we must admit gravita- 
 tion, cohesion, corpuscular attraction, mag- 
 netism, and other centripetal and centri- 
 fugal forces, by which the particles of 
 matter attract and repel each other. New- 
 ton, having discovered this, and demon- 
 strated that these principles cannot be 
 resolved into matter and motion, was led, 
 by analogy and the love of simplicity, to 
 conjecture, but with a modesty and caution 
 peculiar to him, that all the phsenomena of 
 the material world depended upon attract- 
 ing and repelling forces in the particles of 
 matter. But we may now venture to say, 
 that this conjecture fell short of the mark. 
 For, even in the uno rganized kingdom, the 
 
 * See " Essays on the Intellectual Powers, " p. P56, 
 sqq 4to edition.— H. 
 
 t We must except, however, before Reid, among 
 hers, the system of Siiinoza, and, since Reid. those 
 
 otbe 
 
 of Fichfe, Sthcliing, Hegel, ^c- H
 
 CONCLUSION. 
 
 207 
 
 powers by which salts, crystals, spars, and 
 many other bodies, concrete into regular 
 forms, can never be accounted for by at- 
 tracting and repelling forces in the particles 
 of matter. And in the vegetable and ani- 
 mal kingdoms, there are strong indications 
 of powers of a different nature from all the 
 powers of unorganized bodies. We see, 
 then, that, although, in the structure of the 
 material world, there is, without doubt, all the 
 beautiful simplicity consistent with the pur- 
 poses for which it was made, it is not so 
 simple as the great Des Cartes determined 
 it to be ; nay, it is not so simple as the 
 greater Newton modestly conjectured it to 
 be. Both were misled by analogy, and 
 the love of simphcity. One had been 
 much conversant about extension, figure, 
 and motion ; the other had enlarged his 
 views to attracting and repelling forces ; 
 and both formed their notions of the un- 
 known parts of nature, from those with 
 which they were acquainted, as the shepherd 
 Tityrus formed his notion of the city of 
 Rome from his country village : — 
 " Urbem quam dicunt Romam, Meliboee, piitavi 
 Stultus ego, huic nostrEE similem, quo sicpe solemus 
 Pastores ovium teneros depellere fetus. 
 Sic canibus catulos similes, sic matribus hados 
 N('jram : sit- parvis componere magna solebam." 
 
 This is a just picture of the analogical way 
 of thinking. 
 
 But to come to the system of Des Cartes, 
 concerning the human understanding. It 
 was built, as we have observed, upon con- 
 sciousness as its sole foundation, and with 
 ideas" as its materials ; and all his fol- 
 lowers have built upon the same foundation 
 and with the same materials. They acknow- 
 ledge that Nature hath given us various 
 simple ideas. These are analogous to the 
 matter of Des Cartes's physical system. 
 They acknowledge, likewise, a natural 
 power, by which ideas are compounded, dis- 
 joined, associated, compared. This is 
 analogous to the original quantity of motion 
 in Des Cartes's physical system. From 
 these principles, they attempt to explain the 
 phsenomcna of the human understanding, 
 just as in the physical system the phtuno- 
 mena of nature were to be explained by 
 matter and motion. It must, indeed, Ije 
 acknowledged, that there is great simpli- 
 city in this system, as well as in the other. 
 There is such a similitude between the two, 
 as may be expected between children of 
 the same father ; ])ut, as the one has been 
 found to be the child of Des Cartes, and 
 not of Nature, there is ground to think 
 that the other is so likfwise. 
 
 That the natural issue of this system is 
 
 • There is no valid ground (or supposing that 
 Den Cartes meant by ideas au^ht but modifirations 
 of the mind itself. That the tiiajotily iif the t'aitcs- 
 JRniriid not, i« certain, 'iheca^e is, however, diHer. 
 orit with rejjard to Malebranche and Berkeley. Hut 
 uf thia aifaiii. — 11. 
 
 scepticism with regard to everythmg ex- 
 cept the existence of our ideas, and of their 
 necessary relations, which appear upon com- 
 paring them, is evident ; for ideas, being the 
 only objects of thought, and having no ex- 
 istence but when we are conscious of tlieni, 
 it necessarily follows that there is no oliject 
 of our thought which can have a continued 
 and permanent existence- Body and spirit, 
 cause and effect, time and space, to which 
 we were wont to ascribe an existence inde- 
 pendent of our thought, are all turned out 
 of existence by this short dilemma. Either 
 these things are ideas of sensation or re- 
 flection, or they are not : if they are ideas 
 of sensation or reflection, they can have no 
 existence but when we are conscious of 
 them ; if they are not ideas of sensation or 
 reflection, they are words without any 
 meaning.* 
 
 Neither Des Cartes uor Locke perceived 
 this consequence of their system concerning 
 ideas. Bishop Berkeley was the first who 
 discovered it. And what followed upon 
 this discovery ? Why, with regard to the 
 material world, and with regard to space 
 and time, he admits the consequence, That 
 these things are mere ideas, and have no 
 existence but in our minds ; but with regard 
 to the existence of spirits or minds, he does 
 not admit the consequence ; and, if he had 
 admitted it, he must have been an absolute 
 sceptic. But how does he evade this con- 
 sequence with regard to the existence of 
 spirits ? The expedient which the good 
 Bishop uses on this occasion is very re- 
 markable, and shews his great aversion to 
 scepticism. He maintains that we have 
 no ideas of spirits ; and that we can think, 
 and speak, and reason about them, and 
 about their attributes, without having any 
 ideas of them. If this is so, my Lord, what 
 should hinder us from thinking and reason- 
 ing about bodies, and their qualities, with- 
 out having ideas of them ? The Bishop 
 either did not think of tliis question, or did 
 not think fit to give any answer to it. How- 
 ever, we may observe, that, in order to avoid 
 scepticism, he fairly starts out of the Car- 
 tesian system, without giving any reason 
 why he did so in this instance, and in no 
 other. This, indeed, is the only instance of 
 a deviation from Cartesian principles which 
 I have met with in the successors of Des 
 Cartes ; and it seems to have been only a 
 sudden start, occasioned by the terror of 
 sce[iticism ; for, in all other things, Berke- 
 ley's .system is founded upon Cartesian 
 principles. 
 
 Thus we see that Des Cartes and Locke 
 take the road that leads to Hce])ticisni, witii- 
 out knowing the end of it ; but tiiey stop 
 
 • 'I'his dilemma applies to the sensualism of Ixx-ke, 
 but not to the rathmalism of Des ('Hrtis —II
 
 208 
 
 OF THE HUiMAN MIND. 
 
 short for want of lij>ht to carry them farther. 
 Berkeley, frighted at tlie appearance of the 
 dreadful abyss, starts aside, and avoids it. 
 But the author of the " Treatise of Human 
 Nature," more daring and intrepid, without 
 turning aside to the right hand or to the 
 left, like Virgil's Alecto, shoots directly 
 into the gulf: 
 
 " Hie specus horrendum, et swv\ spiracul* Ditis 
 MoMstrantur : rupf oque ingeiis Aclieroiite vorago 
 Pcstiteras aperit fauces." 
 
 4. We may observe. That the account 
 given by the new system, of that furniture 
 of the human understanding which is the 
 gift of Nature, and not the acquisition of our 
 own reasoning faculty, is extremely lame 
 and imperfect. • 
 
 The natural furniture of the human un- 
 derstanding is of two kinds : First, The 
 notions or simple apprehensions which we 
 have of things ; and, secondly, The judi/- 
 mcnts or the belief which we have concern- 
 ing them. As to our notions, the new sys- 
 tem reduces them to two classes — ideas of 
 sensation, and ideas of reflection : the first 
 are conceived to be copies of our sensations, 
 retained in tlie memory or imagination ; 
 the second, to be copies of the operations of 
 our minds whereof we are conscious, in like 
 manner retained in the memory or imagin- 
 ation : and we are taught that these two 
 comprehend all the materials about which 
 the human understandnig is, or can be em- 
 ployed. As to our judgment of things, or 
 the belief which we have concerning them, 
 the new system allows no part of it to be the 
 gift of nature, but holds it to be the acquisi- 
 tion of reason, and to be got by comparing 
 our ideas, and perceiving their agreements 
 or disagreements. Now I take this account, 
 both of our notions, and of our judgments 
 or belief, to be extremely imperfect ; and I 
 shall briefly point out some of its capital 
 defects. 
 
 The division of our notions into ideas of 
 sensation, -j- and ideas of reflection, is con- 
 trary to all rules of logic ; because the 
 second member of the divisiou includes the 
 first. For, can we form clear and just 
 notions of our sensations any other way 
 tluin by reflection ? Surely we cannot. 
 Sen.sation is an operation of the mind of 
 which we are conscious ; and we get the 
 notion of sensation by reflecting upon that 
 which we are conscious of. In like manner, 
 doubting and believing are operations of the 
 mind whereof we are conscious ; and we 
 get the notion of them by reflecting upou 
 what we are conscious of. The ideas of 
 sensation, therefore, are ideas of reflection, 
 
 • The following summary refers principally to 
 I,OL-kc. — H. 
 
 + It inust be remembered that under Sensation 
 Locke and others included Perception proper and 
 Hi-nsa: ion pn per. — ii . 
 
 as much as the ideas of doubting, or be- 
 lieving, or any other ideas whatsoever.* 
 
 But, to pass over the inaccuracy of this 
 division, it is extremely incomplete. For, 
 since .sensation is an operation of the mind, 
 as well as all the other things of which we 
 form our notions by reflection, w^hen it is 
 asserted that all our notions are either 
 ideas of sensation or ideas of reflection, the 
 plain English of this is, That mankind 
 neither do nor can think of anything but 
 of the operations of their own minds. No- 
 thing can be more contrary to truth, or 
 more contrary to the experience of man- 
 kind. I know that Locke, while he main- 
 tained this doctrine, believed the notions 
 which we have of body and of its qualities, 
 and the notions which we have of motion 
 and of space, to be ideas of sensation. But 
 why did he believe this ? Because he 
 believed those notions to be nothing else 
 but images of our sensations. If, there- 
 fore, the notions of body and its qualities, 
 of motion and space, be not images of our 
 sensations, will it not follow that those 
 notions are not ideas of sensation ? Most 
 certainly. -|- 
 
 * I do not see how this criticism on Locke's divi. 
 sion can bedefended, or even excused. It is perfectly 
 evident that Reid here confounds tke proper ideai of 
 sensation — that is, ihe ideas of the qualities of matter, 
 about which sensat'on (perception) is conversant — 
 with the idea of sensation itself— that is, the idea of 
 this faculty as an attribute of mind, and which is the 
 oliject of a refltx consciousness. Nor would it be 
 competentto maintain that Locke, allowing no im- 
 mediate knowledge of aught but of mind and its 
 contents, consequently reduces all our faculties to 
 self-consciousness, and thus abolishes the distinction 
 ol sensation (perception) and reflection, as separate 
 faculties, the one conversant with the qualities of 
 the external world, the other with the qualities of 
 the internal. For, in the first place, it would still 
 be logically competent, on th« hypothesis that mII 
 our knowledge is exclusively of self, to divide the 
 ideas we possessed, into classes, according as these 
 were given as representations of the iion-ego by the 
 ego, or as phjenomena of the ego itself. In th > sr-- 
 cond place, Reid's criticism d<ies not admit of this 
 excuse. But, in the third, if the defence were valid 
 in itself, and here available, the philosophy of lieid 
 himself would be obnoxiou . to a similar criticism. For 
 he makes perception (consequently the object known 
 in perception) an object of consciousness; but con- 
 sciousness, in his view, is only of the pha^nomc^a of 
 mind itself — all consciousness is to him sclf.con. 
 sciousness. Thus, his icrception, as contained under 
 his consciousness, is only cognisant ofthep^o. With 
 all this, however, Reid distinguishes perception and 
 consciousness as special and co-ordinate faculties; 
 perception being conversant about the qualities of 
 matter, as supgeited— tha' is, as represented in the 
 percipieiu sui'ject — consciousness as conversant about 
 I'.erception and the other attributes of mind itself. 
 — With the preceding observations, the reader may 
 compare Priestley's " Examination," p ;i8, and 
 Stewart's " Philosophical Essays," Note N — H. 
 
 t I may here notice—what 1 shall hereafter more 
 fully advert to — that Reid's criticism of Locke, here 
 and elsewhere, proceeds upon the implication that 
 the English philosopher attached the same restricted 
 meaning to the term Sensation that he did himself 
 But this is not ihe case. Locke employed Sensation 
 to denote both the idee and the sentiment of the 
 Cartesians — bo h the perception and the sensation 
 of Reid. To confound this distinction was, indeed, 
 wrong: but this is a separate and special ground of 
 censure, and, in a general criticism of Locke's t.oc-
 
 CONCLUSION. 
 
 209 
 
 There is no doctrine in tlio new system 
 which more directly leads to scepticism 
 than this. And the author of the " Trea- 
 tise of Human Nature" knew very well 
 how to use it for that purpose ; for, if you 
 maintain that there is any such existence 
 as body or spirit, time or place, cause or 
 effect, he immediately catches you between 
 the horns of this dilemma ; your notions of 
 these existences are either ideas of sensa- 
 tion, or ideas of reflection : if of sensation, 
 from what sensation are they copied ? if of 
 reflection, from what operation of the mind 
 are they copied ? 
 
 It is indeed to bo wished inat those who 
 liave written much about sensation, and 
 about the other operations of the mind, had 
 likewise thought and reflected much, and 
 with great care, upon those operations ; but 
 is it not very strange that they will not 
 allow it to be possible for mankind to think 
 of an^-thing else ? 
 
 The account which this system gives of 
 our judgment and belief concerning things, 
 is as far from the truth as the account 
 it gives of our notions or simple appre- 
 hensions. It represents our senses as hav- 
 ing no other offtce but that of furnishing 
 the mind with notions or simple appre- 
 hensions of things ; and makes our judg- 
 ment and belief concerning those things to 
 be acquired by comparing our notions to- 
 gether, and perceiving their agreements or 
 disagreements. 
 
 We have shewn, on the contrary, that 
 every operation of the senses, in its very 
 nature, implies judgment or belief, as well 
 as simple apprehension. Thus, when I feel 
 the pain of the gout in my too, I have not 
 only a notion of i)ain, but a belief of its 
 existence, and a belief of some disorder in 
 iny toe which occasions it ; and this belief 
 is not produced by comparing ideas, and 
 perceivi:ig their agreements and disagree- 
 ments ; it is included in the very nature of 
 the sensation. When I peiceive a tree 
 before me, my faculty of seeing gives me 
 not only a notion or simple apprehension of 
 the tree, but a belief of its existence, and 
 of its figure, distance, and magnitude ; and 
 this judgment or belief is not got by com- 
 paring ideas, it is included m the very na- 
 ture of the perception. We have taken 
 notice of several original principles of 
 belief in the course of this inquiry ; and 
 
 trine, the fact ihat hedid so confound pprccption pro. 
 (leraiid sensation proper, should alwaya be taken into 
 account. J'ut, waving this, what is gained by the 
 dislinclion in iieid's hands? In his docirine, spate, 
 motion, Sic, a« perceived, are only conceptions only 
 nioilincations of sell, suggested, ui some unknown 
 way, on occamnn of the impression made on the sense : 
 ronseijuenlly, in Mie one d(x;trine as in tlie other, 
 what is known is nothiuK hc-yond the adeclions of 
 the ThnikioK sul.jei t. itself ; arid ihi.s is the only ha^is 
 rcfjuired by the idealist aiul sceptic Ci r the f.,uiul,aioii 
 of ihcir lystcum — tl. 
 
 when other facidties of the mind are exa- 
 mined, we .shall find more, which have not 
 occurred in the examination of the five 
 senses. 
 
 Such original and natural judgments are, 
 therefore, a part of that furniture which 
 Nature hath given to the human under- 
 standing. They are the inspiration of the 
 Almighty, no less than our notions or simple 
 apprehensions. They serve to direct us in 
 the common affairs of life, where our rea- 
 soning faculty would leave us in the dark. 
 They are a part of our constitution ; and all 
 the discoveries of our reason are grounded 
 upon them. They make up what is called 
 Ihe commoft sense of mankind ;• and, what 
 is manifestly contrary to any of those first 
 principles, is what we call absurd. The 
 strength of them is good sense, which is 
 often found in those who are not acute in 
 reasoning. A remarkable deviation frorh 
 them, arising from a disorder ui the con- 
 stitution, is what we call lunacy ; as when 
 a man believes that he is made of glass. 
 When a man suffers himself to be reasoned 
 out of the principles of common sense, liy 
 metaphysical arguments, we may call this 
 melaphysical lunacy ; which diflers from 
 the other species of the distemper in this, 
 that it is not continued, but intermittent : 
 it is apt to seize the patient in solitary and 
 speculative moments ; but, when he enters 
 into society. Common Sense recovers her 
 authority. -f A clear explication and enu- 
 meration of the principles of common sense, 
 is one of the chief desiderata in logic. Wo 
 have only considered such of them as oc« 
 curred in the examination of the five 
 senses. 
 
 5. The last observation that I shall make 
 upon the new system, is, that, although it 
 professes to set out in the way of reflection, 
 and not of analogy, it hath retained somo 
 of the old analogical notions concerning tho 
 
 • See Note A — H. 
 
 t No one admits this more promptly than tho 
 sceptic hinisilf See Hume's "'treatise of lUiinaii 
 Nature," Hook I , Part iv., ^ 7, and " Kiujiiiry 
 ConcerniiiK Human Undoistanding," ^ I'i, I'art II. 
 " Nature," says he in the latter, " is always too strong 
 for principle ; and, though a I'yrilionian m ly throw 
 himself or others into a momentary amazement and 
 confusion by his profound reasonings, the tirst and 
 most trivial event in life will put to flight all his 
 doubts ami scruples, and leave liini thcsamein every 
 point of action and speculation with the philosophers 
 of every other sect, or with those who never con. 
 cerned themselves in any philosophical researches. 
 When he awakes from his dream, lie will be the tirst 
 to'join in the laugh .against himself, and to confess 
 that all his ( bjections are mere amusement, and can 
 have-no other tendency than to shew the wliinisical 
 condiiion of mankind, who must act, and reason, 
 and believe, though they arc not able, by their most 
 diligent cmiuiry, to satisfy Iheinselves concerning tliu 
 foundation of the oiieialions, or to remove the ol)jec. 
 tions which may be .raised against them " 
 
 " I.a Nature coiiloiul le« I'yirhoniena," (s.'iyi 
 I'ascal,) "et la liaison < iiiiluiid les Dogiii liislen." 
 Ilow call pliilusojihy be lealizedi' is tluu Ihe (iraiij 
 question. — M.
 
 210 
 
 OF THE HUMAN MIND. 
 
 operations of the mind ; particularly, that 
 things which do not now exist in the mind 
 itself, (k'n only be perceived, remembered, 
 or imagined, by means of ideas or images* 
 of them in the mind, which are the imme- 
 diate objects of perception, remembrance, 
 and imagmation. This doctrine appears 
 evidently to be borrowed from the old sys- 
 tem ; which taught that external thmgs 
 make impressions upon the mind, lilvc the 
 impressions of a seal upon wax ; that it is 
 by means of those impressions that we per- 
 ceive, remember, or imagine them ; and 
 that those impressions must resemble the 
 things from which they are taken. When 
 we form our notions of the operations of the 
 mind by analogy, this way of conceiving 
 them seems to be very natural, and offers 
 itself to our thoughts ; for, as everything 
 which is felt must make some impression 
 upon the body, we are apt to think that 
 everything which is understood must make 
 some impression upon the mind. 
 
 From such analogical reasoning, this 
 opinion of the existence of ideas or images 
 of things in the mind, seems to have taken 
 its rise, and to have been so universally 
 received among philosophers. It was ob- 
 s-^rved already, that Berkeley, in one in- 
 stance, apostatizes from this principle of 
 the new system, by affirming that we have 
 no ideas of spirits, and that we can think of 
 them immediately, without ideas. But I 
 know not whether in this he has had any 
 followers. There is some diflerence, like- 
 wise, among modern philosophers with re- 
 gard to the ideas or images by which we 
 perceive, remember, or imagine sensible 
 things. For, though all agree in the exist- 
 ence of such images,-}- they differ about their 
 place ; some placing them in a particular 
 part of the brain, where the soul is thought to 
 have her residence, and others placing them 
 in the mind itself. Des Cartes held the first 
 of these opinions iX to which Newton seems 
 likewise to have inclined ; for he proposes 
 this query in his " Optics :" — " Annon sen- 
 aorium animalium est locus cui substantia 
 sentiens adest, et in quem sensibiles rerum 
 species per nervos et cerebrum deferuntur, 
 ut ibi prsesentes a prtesente sentiri pos- 
 
 • That is, Dy represrniativr entities dijf! rent from 
 the modes of the tiiind itself. This doctrine, I have 
 already noticed, is attributed by Reidtoo universally 
 to philosophrs; and is also a comparatively unim- 
 portant circumstance in reference to the Idealist and 
 Sceptic. See Note C— H. 
 
 + S(e last note. Berkeley din hold the hypothesis 
 of Ideas as understood by Reid. — H. 
 
 X An unqualified error, arising from not under. 
 Jtanding the ambiguous language of Des C; rtes ; 
 whoi calls, by the common name of Ideas, both the 
 organic motions in the brain, of which the mind, in 
 his doctrine, necessarily knows nothing, and the re. 
 presentations in the-mind itself, hypprphysically de- 
 termincd on occasion of those motions, and of which 
 alone the mind is cognizant. Rut of this under the 
 " iihsays on the Intellectual Powers." — H. 
 
 sint ?" But Locke seems to place the ideaa 
 of sensible things in the mind ;* and that 
 Berkeley, and the author of the " Treatise 
 of Human Nature," were of the same 
 opinion, is evident. The last makes a very 
 curious application of this doctrine, by en- 
 deavouring to prove from it. That the mind 
 either is no substance, or that it is an ex- 
 tended and divisible substance ; because the 
 ideas of extension cannot be in a subject 
 which is indivisible and unextended. 
 
 I confess I thuik his reasoning in this, 
 as in most cases, is clear and strong. For 
 whether the idea of extension be only 
 another name for extension itself, as Ber- 
 keley and this author assert ; or whether 
 the idea of extension be an image and resem- 
 blance of extension, as Locke conceived ; 
 I appeal to any man of common sense, 
 whether extension, or any image of exten- 
 sion, can be in an unextended and indi- 
 visible subject.-)- But while I agree with 
 him in his reasoning, I would make a differ- 
 ent application of it. He takes it for grant- 
 ed, that there are ideas of extension in the 
 mind ; and thence infers, that, if it is at all 
 a substance, it must be an extended and 
 divisible substance. On the contrary, I 
 take it for granted, upon the testimony of 
 common sense, that my mind is a substance 
 — that is, a permanent subject of thought ; 
 and my reason convinces me that it is an 
 unextended and indivisible substance ; and 
 hence I infer that there cannot be in it 
 anything that resembles extension. If this 
 reasoning had occurred to Berkeley, it 
 would probably have led him to acknow- 
 ledge that we may think and reason con- 
 cerning bodies, without having ideas of them 
 in the mind, as well as concerning spirits. 
 
 I intended to have examined more par- 
 ticularly and fully this doctrine of the ex- 
 istence of ideas or images of things in the 
 mind ; and likewise another doctrine, which 
 is founded upon it — to wit. That judgment 
 or belief is nothing but a perception of the 
 agreement or disagreement of our ideas ; 
 but, having already shewn, through the 
 course of this inquiry, that the operations 
 of the mind which we have exammed, give 
 no countenance to either of these doctrines, 
 and in many things contradict them, I have 
 thought it proper to drop this part of my 
 design. It may be executed with more 
 advantage, if it is at all necessary, after in- 
 quiring into some other powers of the human 
 understanding. 
 
 • Locke's opinion on this point is as obscure and 
 doubtful as that of Des Cartes is clear and certain. 
 But Reid is probably riglit. — H 
 
 -f- I do not recollect seeing any argument raised in 
 favour of materialism, from the fact, that, spice or 
 extension is.a notion necessary to the mind ; and yet 
 it might, with some show of plausibility, be main, 
 tained, that extension is a necessary form of thought, 
 because the thinking principle is itself extended —H
 
 CONCLUSION. 
 
 211 
 
 Although we have examined ouly the five 
 senses, and the principles of the human 
 mind which are employed about them, or 
 such as have fallen in our way in the course 
 of this examination, we shall leave the 
 further prosecution of this inquiry to future 
 deliberation. The powers of memory, of 
 imagination, of taste, of reasoning, of moral 
 perception, the will, the passions, the affec- 
 tions, and all the active powers of the soul, 
 present a vast and boundless field of philo- 
 sophical disquisition, which the author of 
 this inquiry is far, from thinking himself 
 able to survey with accuracy. Many authors 
 of ingenuity, ancient and modern, have 
 made excursions into this vast territory, 
 and have communicated useful observations : 
 but there is reason to believe that those 
 who have pretended to give us a map of the 
 ■whole, have satisfied themselves with a very 
 inaccurate and incomplete survey. If Ga- 
 lileo had attempted a complete system of 
 
 natural philosophy, he had, probably, done 
 little service to mankind ; but by confining 
 himself to what was withui his comprehen- 
 sion, he laid the foundation of a system of 
 knowledge, which rises by degrees, and 
 does honour to the human understanding. 
 Newton, building upon this foundation, and, 
 in like manner, confining his inquiries to 
 the law of gravitation and the properties of 
 light, performed wonders. If he had at- 
 tempted a great deal more, he had done a 
 great deal less, and perhaps nothing at all. 
 Ambitious of followmg such great examples, 
 with unequal steps, alas ! and unequal 
 force, we have attempted an inquiry only 
 into one little corner of the human mmd — 
 that corner which seems to be most exposed 
 to vulgar observation, and to be most easily 
 comprehended ; and yet, if we have deline- 
 ated it justly, it must be acknowledged that 
 the accounts heretofore given of it wer<» 
 very lame, and wide of tlie truth.
 
 ESSAYS 
 
 ON TUB 
 
 INTELLECTUAL POWERS OF MAN, 
 
 liv THOMAS ItEin, U.I)., F.RS.E., 
 
 THOFESSOR OF MOUAI, rini.OSOrilY IN THE UNIVERSITY OF CLAS.'WrV, 
 " Who hath |>ut wisdom In the inward parta f* - J""
 
 C^ This impression of the " Essays on the Intellectual Powers," is made from the 
 only authentic edition — that of 1785, in 4to. For the convenience of reference the pages 
 of that edition are distinguished in the present ; and by these pages I shall always, in 
 the notes, prospeclively, quote. They will be found marked both in the text and on the 
 lower margin, — H.
 
 DEDICATION. 
 
 TO 
 
 MR DUGALD STEWART, 
 
 f.ATELY PROFESSOR OF MATHEMATICS, NOW PROFESSOR OF MORAL PHILOSOPHY, 
 
 ANO 
 
 DR JAMES GREGORY, 
 
 PROFESSOR OF THE THEORY OF PHYSIC IN THE UNIVERSITY OF EDINBURGH.* 
 
 My Dear Friends, — I know not to 
 whom I can address these Essays with 
 more propriety than to you ; not only on 
 account of a friendship bej^uu in early life 
 on your part, though in old age on mine, 
 and in one of you I may say hereditary ; 
 nor yet on account of that correspondence 
 in our literary pursuits and amusements, 
 which has always given me so great plea- 
 sure ; but because, if these Essays have 
 any merit, you have a considerable share 
 in it, having not only encouraged me to hope 
 that [iv.] they may be useful, but favoured 
 me with your observations on every part of 
 them, both before they were sent to the 
 press, and while they were under it. 
 
 I have availed myself of your observa- 
 tions, so as to correct many faults that 
 might otherwise have escaped me ; and I 
 have a very grateful sense of your friend- 
 ship, in giving this aid to one who stood 
 much in need of it ; having no shame, but 
 much pleasure, in being instructed liy those 
 who formerly were my pupils, as one of you 
 was. 
 
 It would be ingratitude to a man whose 
 memory I most highly respect, not to men- 
 tion my obligations to the late Lord Karnes, 
 for the concern he was pleased to take in 
 this Work. Having seen a small part of 
 it, he urged me to carry it on ; took acount 
 of my i)rogres8 from time to time ; revised 
 it more than once, as far as it was carried, 
 before his deatii ; ami gave me his observa- 
 tions on it, both with respect to the matter 
 and the expression. On some points wo 
 
 • Sec above, in " Corrcspmiilencc," p._ 05, a.— H. 
 Oii- -vi.l 
 
 differed in opinion, and debated them 
 keenly, both in conversation and by many 
 letters, without any abatement of his affec- 
 tion, or of his zeal for the work's being 
 carried on and published : for he had too 
 much liberality of mmd not to allow to [v.] 
 others the same liberty in judging which he 
 claimed to himself. 
 
 It is difficult to say whether that worthy 
 man was more eminent in active life or 
 in speculation. Very rare, surely, have 
 been the instances where the talents for 
 both were united in so eminent a degree. 
 
 His genius and industry, in many differ- 
 ent branches of literature, will, by his 
 works, be known to posterity : his private 
 virtues and public spirit, his assiduity, 
 through a long and laborious life, in many 
 honourable public offices with which he was 
 entrusted, and his zeal to encourage and 
 promote everything that tended to tho 
 improvement of his counti-y in laws, litera- 
 ture, commerce, manufactures, and agricul- 
 ture, are best known to his frienils and 
 contemporaries. 
 
 The favourable opinion whicli ho, and 
 you my friends, were pleased to express 
 of this work, has been my chief encourage- 
 ment to lay it before the public ; and per- 
 haps, without that encouragement, it had 
 never seen the light : for I have always 
 found, that, witliout social intercourse, even 
 a favourite speculation languishes; and 
 thatwecamiot help tliiiikiiig the betti'rofour 
 own opinions Lvi-J when they are ap|)roved 
 by those whom we esteem good judges. 
 
 Yon know that the snbslanco of these 
 Essays was delivcreil annually, for nioro
 
 216 
 
 niEFACC. 
 
 than twenty years, in Lectures to a large 
 body of tlic more advanced students in this 
 University, and for several years before, in 
 another University. Those who heard me 
 with attention, of \\h()m I presume there 
 are some hundreds alive, will i-ecoguise the 
 doctrine which they heard, some of them 
 thirty years ago, delivered to them more 
 diffusely, and with the repetitions and illus- 
 trations proper for such audiences, 
 
 I am afraid, indeed, that the more intel- 
 ligent reader, who is conversant in such 
 abstract subjects, may think that there are 
 repetitions still left, which might be spared. 
 Such, I hope, will consider, that what to 
 
 one reader is a superfluous repetition, to 
 the greater part, less conversant in such 
 subjects, may be very useful. If this apo- 
 logy be deemed insufficient, and be thought 
 to be the dictate of laziness, I claim some 
 indulgence even for that laziness, at my 
 period of life, [vii.] 
 
 You who are in the prime of life, with 
 the vigour which it inspires, will, I hope, 
 make more happy advances in this or in any 
 other branch of science to which your taleuta 
 may be applied. 
 
 Tho, Reid, 
 Glasgow College, June I, 1785. 
 
 PREFACE. 
 
 Human knowledge may be reduced to 
 two general heads, according as it relates 
 to body or to mind ; to thmgs material or 
 to things intellectual.* 
 
 The whole system of bodies in the imi- 
 verse, of which we know but a very small 
 part, may be called the Material World ; 
 the whole system of minds, from the infinite 
 Creator to the meanest creature endowed 
 with thought, may be called the Intellectual 
 World, These are the two great kingdoms 
 of nature-f that fall within our notice ; 
 and about the one, or the other, or things 
 pertaining to them, every art, every science, 
 and every human thought is employed ; nor 
 can the boldest flight of imagination carry 
 us beyond their limits. 
 
 Many things there are, indeed, regarding 
 the nature and the structure both of body 
 and of mind, which our faculties cannot 
 reach ; many difficulties which the ablest 
 philosopher cannot resolve : but of other 
 
 * See Stewart's " Life and Writings of Reid," 
 supra, p. It ; and hi3 " Elements," vol. I., introduc- 
 tion ; Jouffroy, in the preface to his " Oeuvres de 
 Reid," t. i., pp. 23-53. This important Preface will 
 soon be made generally accessible to the British pub. 
 lie by a highly competent translator. — H. 
 
 f The term Nature is used sometimes in a wider, 
 sometimes in a narrower extension. When employed 
 in its most extensive meaning, it embraces the two 
 worlds ot mind and matter. When employed in its 
 more restricted signification, it is a synonyme for the 
 latter only, and is then used in contradistinction to 
 the former. In the Greek philosophy, the word 
 Cua-ii was general in its meaning; and the great 
 branch of philosophy styled " physical or physiolo- 
 gical," included under it not only the sciences of 
 matter, but also those of mind. With us, the term 
 Nature is more vaguely extensive than the terms, 
 physics, phi/sical, physiology, physiological, or even 
 tnan the adjective natural; whereas, in the philo- 
 sophy of Germany, Natur, and its correlatives, 
 wlu thcr of Greek or Latin derivation, are, in general, 
 expressive of the world of matter in contrast to the 
 world of intelligence. — H. 
 
 Ivii.-2J 
 
 natures, if any other there be, we have no 
 knowledge, no conception at all. 
 
 That everything that exists must be either 
 corporeal or incorporeal is evident. But 
 it is not so evident that everything [2] that 
 exists must either be corporeal or endowed 
 with thought. Whether there be in the 
 universe beings which are neither extended, 
 solid, and inert, like body, nor active and 
 intelligent, like mmd, seems to be beyond 
 the reach of our knowledge. There appears 
 to be a vast interval between body and 
 mind ; and whether there be any interme- 
 diate nature that connects them together, 
 we know not. 
 
 We have no reason to ascribe intelli- 
 gence, or even sensation, to plants ; yet 
 there appears in them an active force and 
 energy, which cannot be the result of any 
 arrangement or combination of inert matter. 
 The same thmg may be said of those powers 
 by which animals are nourished and grow, 
 by which matter gravitates, by which mag- 
 netical and electrical bodies attract and 
 repel each other, and by which the parts of 
 solid bodies cohere. 
 
 Some have conjectured that the phseno- 
 mena of the material world which require 
 active force, are produced by the continual 
 operation of intelligent beings : others have 
 conjectured that there may be in the uni- 
 verse, beings that are active, without in- 
 telligence, which, as a kind of incorporeal 
 machinery, contrived by the supreme wis- 
 dom, perform their destined task without 
 any knowledge or intention.* But, laying 
 aside conjecture, and all pretences to deter- 
 mine in things beyond our reach, we must 
 
 + Like the tripods of Vulcan— 
 
 ' 0?{a 01 ivro/xocrci Suet ^vitkIki' iymcc — H.
 
 PREFACE. 
 
 217 
 
 rest in this, that body and mind are the 
 only kinds of being of which we can have 
 any knowledge, or can form any concep- 
 tion. If there are other kinds, they are 
 not discoverable by the faculties which God 
 hath given us ; and, with regard to us, are 
 as if they were not. [3] 
 
 As, therefore, all our knowledge is con- 
 fined to body and muid, or things belonging 
 to them, there are two great branches of 
 philosophy, one relating to body, the other 
 to mmd. ' The properties of body, and the 
 laws that obtain in the material system, are 
 the objects of natural philosophy, as that 
 word is now used. The branch which 
 treats of the nature and operations of minds 
 has, by some, been called Pncumatology.* 
 And to the oueor the otherof these branches, 
 the principles of all the sciences belong. 
 
 What variety there may be of minds or 
 thinking beings, throughout this vast uni- 
 verse, we cannot pretend to say. We dwell 
 in a little corner of God's dominion, dis- 
 joined from the rest of it. The globe which 
 we inhabit is but one of seven planets that 
 encircle our sun. What various orders of 
 beings may inhabit the other six, their 
 secondaries, and the comets belonging to 
 our system, and how many other suns may 
 be encircled with like systems, are things 
 altogether hid from us. Although human 
 reason and indu&try have discovered, with 
 great accuracy, the order and distances of 
 the planets, and the laws of their motion, 
 we have no means of corresponding with 
 them. That they may be the habitation of 
 animated beings, is very probable ; but of 
 the nature or powers of their inhabitants, 
 we are perfectly ignorant. Every man is 
 conscious of a thinking principle, or mind, 
 in himself; and we have sufficient evidence 
 of a like principle in other men. The 
 actions of brute animals shew that they 
 have some thinking principle, though of a 
 nature far inferior to the human mind. And 
 everything about us may convince us of the 
 existence of a supreme mind, the ]Maker and 
 Governor of the universe. These are all 
 the minds of which reason can give us any 
 certain knowledge. [4] 
 
 The mind of man is the noblest work of 
 God whicli reason discovers to us, and, 
 therefore, on account of its dignity, deserves 
 our study.-]- It nuist, indeed, be acknow- 
 ledged, that, although it is of all objects the 
 nearest to us, and seems the most within 
 cur reach, it is very difficult to attend to 
 its operations so as to form a distinct notion 
 
 • Now properly suporscdcil liy the term I'sychul- 
 iit^y ■ to v-iiieh no eoinpeteiil olijietioii can be iiiadc, 
 and wIikIi aTrords u«— what the various clunisy [icri. 
 piirasi's in u-e do not — a convenient adjcclive.ps^cAy- 
 luf;iciil. — \ I. 
 
 \ •• On earth," says a forgotten pliilosojiher, 
 " there is nottiinj! great Imt Man; in mmm there is 
 uutiiinK (;r(at l)iit Mmd. "--il 
 
 1.3— .'>l 
 
 of them i and on that account there is no 
 branch of knowledge in which the ingenious 
 and speculative have fallen into so great 
 errors, and even absurdities. These errors 
 and absurdities have given rise to a general 
 prejudice against all inquiries of this nature. 
 Because ingenious men have, for many 
 ages, given difi'erent and contradictory 
 accounts of the powers of the mind, it is 
 concluded that all speculations concerning 
 them are chimerical and visionary. 
 
 But whatever effect this prejudice may 
 have with superficial thiidicrs, the judicious 
 ■svill not be apt to be carried away with it. 
 About two hundred years ago, the opinions 
 of men m natural philosophy were as various 
 and as contradictory as they are now con- 
 cerning the powers of the mind. Galileo, 
 Torricelli, Kepler, Bacon, and Newton, 
 had the same discouragement in their 
 attempts to throw light upon the material 
 system, as we have with regard to the in- 
 tellectual. If they had been deterred by 
 such prejudices, we should never have 
 reaped the benefit of their discoveries, 
 which do honour to human nature, and will 
 make their names immortal. The motto 
 which Lord Bacon prefixed to some of his 
 writings was worthy of his genius, Jnveniam 
 viam aul faciam. * 
 
 There is a natural order in the progress 
 of the sciences, and good reasons may be 
 assigned why the philosophy of body should 
 [5] be el:Ier sis/er to that of mind, and of a 
 quicker growth ; but the last hath the prin- 
 ciple of life no less than the first, and will 
 grow up, though slowly, to maturity. The 
 remains of ancient philosophy upon this 
 subject, are venerable ruins, carrying the 
 marks of genius and industry, sufficient to 
 inflame, but not to satisfy our curiosity. In 
 later ages, Des Cartes was the first that 
 pointed out the road we ought to take in 
 those dark regions. Malebranche, Arnauld, 
 Locke, Berkeley, Buffier, Ilutcheson, 
 Butler, Hume, Price, Lord Karnes, have 
 laboured to make discoveries— nor have they 
 laboured in vain; for, however different 
 and contrary their conclusions are, how- 
 ever sceptical some of them, they have all 
 given new light, and cleared the way to those 
 who shall come after them. 
 
 We ought never to despair of human 
 genius, but rather to hope that, in time, 
 it may produce a system of the powers and 
 operations of the human mind, no less cer- 
 tain than those of o|)tics or astroiioniy. 
 
 This is the more devoutly to be wished, 
 that a distinct knowledge of the powers of 
 the mind would nndoulitedly give great light 
 any otlur ))i;uicin'S of science. Mr 
 le hath justly observed, that " all tin' 
 
 to ma 
 Hume 
 
 • .Sec Mr Rtcwmfg " rhilosoi>hlrnl Essays," J're- 
 liininary liisstitdion, ch, ti
 
 218 
 
 PREFACE. 
 
 sciences have a relation to human nature ; 
 and, however wide any of them may seem 
 to run from it, they still return back by one 
 passage or another. This is the centre and 
 capital of the sciences," which, being once 
 masters of, we may easily extend our con- 
 quests everywhere." 
 
 The faculties of our minds are the tools 
 and engines we must use in every disquisi- 
 tion ; and the better we understand their [C] 
 nature and force, the more successfully we 
 shall be able to apply them. Mr Locke 
 gives this account of the occasion of his 
 entering upon his essay concerning human 
 understanding : — " Five or six friends," 
 says he, " meeting at my chamber, and dis- 
 coursing on a subject very remote from 
 this, found themselves quickly at a stand 
 by the difficulties that rose on every side. 
 After we had for a while puzzled ourselves, 
 without coming any nearer to a resolution 
 of those doubts that perplexed us, it came 
 into my thoughts that we took a wrong 
 course ; and that, before we set ourselves 
 upon inquiries of that nature, it was neces- 
 sary to examine our own abilities, and see 
 what objects our understandings were fitted 
 or not fitted to deal with. This I proposed 
 to the company, who all readily assented ; 
 and thereupon it was agreed that this should 
 be our first enquiry." If this be commonly 
 the cause of perplexity in those disquisi- 
 tions which have least relation to the mind, 
 it must be so much more in those that have 
 an immediate connection with it. 
 
 The sciences may be distinguished into 
 two classes, according as they pertain to the 
 material or to the intellectual world. The 
 various parts of natural philosophy, the 
 mechanical arts, chemistry, medicine, and 
 agriculture, belong to the first ; but, to the 
 last, belong grammar, logic, rhetoric, na- 
 
 * Hume probably had the siying of Polybius in 
 liis eye, who calls History the mother city (^jjTjoa-o- 
 Ki; ) of Philosophy.— H. 
 
 [6- 7] 
 
 tural theology, morals, jurisprudence, law. 
 politics, and the fine arts. The know- 
 ledge of the human mind is the root from 
 which these grow, and draw their nourish- 
 ment." Whether, therefore, we consider 
 the dignity of this subject, or its subser- 
 viency to science in general, and to the 
 noblest branches of science in particular, it 
 highly deserves to be cultivated. [7] 
 
 A very elegant writer, on the sublime and 
 beaut'iful,-\ concludes his account of the 
 passions thus : — " The variety of the pas- 
 sions is great, and worthy, in every branch 
 of that variety, of the most diligent inves- 
 tigation. The more accurately we search 
 into the human mind, the stronger traces 
 we everywhere find of His wisdom who made 
 it. If a discourse on the use of the parts of 
 the body may be considered as a hymn to 
 the Creator,:]: the use of the passions, 
 which are the organs of the mind, cannot 
 be barren of praise to Him, nor unproductive 
 to ourselves of that noble and uncommon 
 union of science and admiration, which a 
 contemplation of the works of infinite Wis- 
 dom alone can afford to a rational mind ; 
 whilst referring to Him whatever we find of 
 right, or good, or fair, in ourselves, dis- 
 covering His strength and wisdom even in our 
 own weakness and imperfection, honouring 
 them where we discover them clearly, and 
 adoring their profundity where we are lost 
 in our search, we may be inquisitive with- 
 out impertinence, and elevated without 
 pride ; we may be admitted, if I may dare 
 to say so, into the counsels of the Almighty, 
 by a consideration of his works. This ele- 
 vation of the mind ought to be the principal 
 end of all our studies, which, if they do not 
 in some measure effect, they are of very 
 little service to us." 
 
 * It is justly observed by M. Jouffroy, that the 
 division here enounced is not in principle identical 
 with that previously propounded. — H. 
 
 t Burke.— H. 
 
 t Galeix is referred to— H.
 
 ESSAYS 
 
 ON TUB 
 
 INTELLECTUAL POWERS OF MAN. 
 
 ESSAY I. 
 
 PRELIMINARY. 
 
 CHAPTER I. 
 
 EXPLICATION OF WORDS. 
 
 There is no greater impediment to the 
 advancement of knowledge than the ambi- 
 guity of words. To this chiefly it is owing 
 that we find sects and parties La most 
 brandies of science ; and disputes which 
 are carried on from age to age, without being 
 brought to an issue. 
 
 Sophistry has been more effectually ex- 
 cluded from mathematics and natural 
 philosophy than from other sciences. In 
 mathematics it had no place from the begin- 
 ning ; matheraaticians having had the wis- 
 dom to define accurately the terms they use, 
 and to lay down, as axioms, the first prin- 
 ciples on which their reasoning is grounded. 
 Accordingly, we find no parties among ma- 
 thematicians, and hardly any disputes.* [10] 
 
 In natural philosophy, there was no less 
 sophistry, no less dispute and uncertainty, 
 than in other sciences, until, about a cen- 
 tury and a half ago, this science began to be 
 built upon the foundation of clear defini- 
 tions and self-evident axioms. Since that 
 time, the science, as if watered with the 
 dew of Heaven, hath grown apace ; dis- 
 putes have ceased, truth hath prevailed, 
 and the science hath received greater in- 
 crease in two centuries than in two thous- 
 and years before. 
 
 It were to be wished that this method, 
 wliich hath been so successful in those 
 branches of science, were attempted in 
 others ; for definitions and axioms are the 
 foundations of all science. But that defini- 
 tions may not be sought where no defini- 
 tion can be given, nor logical definitions be 
 attempted where the subject does not admit 
 of them, it may be proper to lay down some 
 general principles concerning definition, for 
 
 " It was not the superior wiBcloin iif mathoiiia- 
 ticiarit, but the Hiiii|)l<> aii<l p.ilipahlccliBractcr nl their 
 olijcct-matler, which (Ictcrmiiied the did'creiice.— II. 
 
 [9-11] 
 
 the sake of those who are less conversant 
 in this branch of logic. 
 
 When one undertakes to explain any art 
 or science, he will have occasion to use 
 many words that are common to all who 
 use the same language, and some that are 
 peculiar to that art or science. Words of 
 the last kind are called terms of the art, and 
 ought to be distinctly explained, that their 
 meaning may be understood. 
 
 A definition* is nothing else but an ex- 
 plication of the meaning of a word, by words 
 whose meaning is already known. Hence 
 it is evident that every word cannot be 
 defined ; for the definition must consist of 
 words ; and there could be no definition, if 
 there were not words previously understood 
 without definition. Common words, there- 
 fore, ought to be used in their common 
 acceptation ; and, when they have diil'erent 
 acceptations in common language, these, 
 when it is necessary, ought to be distin- 
 guished. But they require no definition. 
 It is sufficient to define words that are un- 
 common, or that are used in an micommon 
 meaning. 
 
 It may farther be observed, that there 
 are many words, wliich, though they may 
 need explication, cannot be logically defined. 
 A [ 11 ] logical definition — that is, a strict and 
 proper definition — must express the kind 
 [genus] of the thing defined, and the spe- 
 cific differenco by which the sjiecies defined 
 is distinguished from every other species 
 behinging to that kind. It is natural to tlio 
 mind of man to class things imdcr various 
 kinds, and again to subdivide every kind 
 into its various species. A sjiecies may 
 often be subdivided into subordinate species, 
 and then it is considered as a kind. 
 
 From what has been sai<l of logical defi- 
 nition, it is evident, that no word can bo 
 logically defiiieil wliich does not denote a 
 
 • III what follows, there U a confusion of drfliii- 
 tioMs v.-iljiil ami rni/, wUiih fhoulil have been ca:«- 
 fiillv (li-liiiKoishcd.— II.
 
 220 
 
 ON THE INTELLECTUAL POWERS. 
 
 [[essay I. 
 
 species ; because such things only can have 
 a specific difference ; and a specific differ- 
 ence is essential to a logical definition. 
 On this account there can be no logical 
 definition of mdividual things, such as 
 London or Paris. Individuals arc distin- 
 guished either by proper names, or by acci- 
 dental circumstances of time or place ; but 
 they have no specific difference ; and, there- 
 fore, though they may be known by pro- 
 per names, or may be described by circum- 
 stances or relations, they cannot be defined.* 
 It is no less evident that the most general 
 words cannot be logically defined, because 
 there is not a more general term, of which 
 they are a species. 
 
 Nay, we cannot define every species of 
 thmgs, because it happens sometimes that 
 we have not words to express the specific 
 difference. Thus, a scarlet colour is, no 
 doubt, a species of colour ; but how shall 
 we express the specific difference by which 
 scarlet is distinguished from green or blue ? 
 The difference of them is immediately per» 
 ceived by the eye ; but we have not words 
 to express it. These things we are taught 
 by logic. 
 
 Witliout having recourse to the prui- 
 ciples of logic, we may easily be satisfied 
 that words cannot be defined, which signify 
 things perfectly simple, and void of all com- 
 position. This observation, I think, was 
 first made by Des Cartes, and afterwards 
 more fully illustrated by Locke. -f- And, 
 however obvious it appears to be, many in- 
 stances may be given of great philosophers 
 who have perplexed [12] and darkened the 
 subjects they have treated, by not knowing, 
 or not attending to it. 
 
 When men attempt to define things which 
 cannot be defined, their definitions will 
 always be either obscure or false. It was 
 one of the capital defects of Aristotle's phi- 
 losophy, that he pretended to define the 
 simplest things, which neither can be, nor 
 need to be defined — such as time and mo- 
 tion.'!^ Among modern philosophers, I 
 
 * It is well said by tlie old logicians, Omnis in. 
 tuitiva notitia est definitio ; — that is, a view of the 
 thins itielj is its best drjinition. Ar.:! 'his is true, 
 both of the objects of sense, and of the objects of self- 
 consciousness. — H. 
 
 ■f Thia is incorrect. Des Cartes has little, and 
 I.ocke no title to praise for this observation. It had 
 been made by Aristotle, and after him l.y many 
 others; while, subsequent to Des Cartes, and pre. 
 vioi'S to Locke, Pascal and the Port- Uoyal J,ogicians, 
 to say nothing ofa paper of Leibnitz, in l(J81, had re. 
 duced it to a matter of commonplace. In this instance, 
 Lockecan, indeed, beprowdaborrower. Mr Stewart 
 (" Philosophical Kssays,"' Note A) is wron.i; in think- 
 ing that, after Des Cartes, Lord Stair is tlie earliest 
 philosopher by whom this logical principle was 
 enouncc<l ; for Stair, as a writer, is subsequent to 
 the authors adduced — H. 
 
 X There is not a liitic, however, to be said in vin- 
 dication of Aristotle's defmilions. Leibnitz is not 
 the only modern philosopher who has applauded that 
 of Motion, which requires, however, some illi s- 
 tration of the special significance of its terms — H. 
 
 know none that has abused definition bo 
 much as Carolus [Christiauus] Wolfius, the 
 famous German philosopher, who, in a 
 work on the human mind, called " Psycho- 
 logia Empirica," consisting of many hun- 
 dred propositions, fortified by demon- 
 strations, with a proportional accompani- 
 ment of definitions, corollaries, and scholia, 
 has given so many definitions of thing« 
 which cannot be defined, and so many de- 
 monstrations of things self-evident, that 
 the greatest part of the work consists of 
 tautology, and ringing changes upon 
 words. " 
 
 There is no subject in which there is 
 more frequent occasion to use words thav 
 cannot be logically defined, than in treating 
 of the powers and operations of the mind. 
 The simplest operations of our minds must 
 all be expressed by words of this kind. No 
 man can explain, by a logical definition, 
 what it is to Ihink, to apprehend, to believe, 
 to vjill, to desire. Every man who under- 
 stands the language, has some notion of th« 
 meaning of those words ; and every man 
 who is capable of reflection may, by attend- 
 ing to the operations of his own mind, 
 which are signified by them, form a clear 
 and distinct notion of them ; but they can- 
 not be logically defined. 
 
 Since, therefore, it is often impossible to 
 define words which we must use on this 
 subject, we must as much as possible use 
 common words, in their common accepta- 
 tion, pointing out their various senses where 
 they are ambiguous ; and, when we are 
 obliged to use words less common, we must 
 endeavour to explain them [13] as well aa 
 we can, witliout affectmg to give logical de- 
 finitions, when the nature of the thing does 
 not allow it. 
 
 The following observations on the mean- 
 ing of certain words are intended to supply, 
 as far as we can, the want of definitions, by 
 preventing ambiguity or obscurity in the 
 use of them. 
 
 1. By the mind of a man, we understand 
 that in him which thinks, remembers, rea- 
 sons, wills. -f The essence both of body and 
 of mind is unknown to us. We know cer- 
 tain properties of the first, and certain oper- 
 ations of the last, and by these only we can 
 define or describe them. Wc define body 
 to be that which is extended, solid, move- 
 able, divisible. In like manner, we define 
 mind to be that which thinks. We are con- 
 cious that we think, and that we have a 
 variety of thoughts of different kinds — such 
 as seeing, hearing, remembering, delibe- 
 rating, resolving, loving, hatmg, and many 
 
 » This judgment is not false j but it is exaggerated 
 — II. 
 
 t This corresponds to Aristotle's second definition 
 of tlie soul, or that n posteriori, ^'ide svjira, p. 203 
 a, note ».— H.
 
 CHAP. I 
 
 ] 
 
 EXPLICATION OF WORDS. 
 
 221 
 
 other liiii'ds of thought— all which we are 
 taiiglit by nature to attribute to one internal 
 principle ; and this principle of thought we 
 call the mind or soul of a man. 
 
 2. By the operations* of the mind, we un- 
 derstand every mode of thinking of which 
 we are conscious. 
 
 It deserves our notice, that the various 
 modes of thinking have always, and in all 
 languages, as far as we know, been called 
 by the name of operations of the mind, or 
 by names of tlie same import. To body 
 we ascribe various properties, but not oper- 
 ations, properly so called : it is extended, 
 divisible, moveable, inert ; it continues iu 
 any state in which it is put ; every change 
 of its state is the effect of some force im- 
 pressed upon it, and is exactly proportional 
 to the force impressed, and iu the precise 
 direction of that force. These are the ge- 
 neral properties of matter, and these are 
 not operations ; on the contrary, they all 
 imply its being a dead, inactive thing, 
 which moves only as it is moved, and acts 
 only by being acted upon.-f- [14] 
 
 But the mind is, from its very nature, a 
 living and active being. Everythmg we 
 know of it implies life and active energy ; 
 and the reason why all its modes of thinking 
 are called its operations, is, that in all, or in 
 most of them, it is not merely passive, as 
 body is, but is really and properly active. 
 
 Iu all ages, and in all languages, ancient 
 and modern, the various modes of thinking 
 have been expressed by words of active 
 signification, such as seeing^ hearing, reason- 
 ing, willing, and the like. It seems, there- 
 fore, to bo the natural judgment of man- 
 kind, that the mind is active in its various 
 ways of thinking : and, for this reason, they 
 are called its operations, and are expressed 
 by active verbs. 
 
 It may be made a question, What regard 
 is to be paid to this natural judgment ? 
 May it not be a vulgar error ? Pliilosophors 
 who think so have, no douht, a right to be 
 heard. But, until it is proved that the 
 mind is not active in thinking, but merely 
 passive, the common language with regard 
 to its operations ought to be used, and ought 
 not to give place to a phraseology invented 
 by philosophers, which implies its being 
 merely passive. 
 
 3. The words power and fanVy, which 
 are often used in speaking of the mind, 
 need little explication. Kvery operation 
 supposes a power in the being that o])er- 
 rates ; for to suppose anything to operate, 
 which has no power to operate, is mani- 
 festly absurd. But, on the other hand. 
 
 * Oprrafwn, Act, Knrrpi/, aro iiparly convertible 
 tcrina ; aii<l arc oppoaeil to luirulli/, (ii( wliicli niiui],) 
 a» Uwiicluiil t(( llw putinliat —II. 
 
 t " Matiriac il.iturn tsl loci, bciI cniitri' Mi'ini." 
 
 ftlAMl.ii > — 11. 
 
 Lu. ivj 
 
 there is no absurdity in supposing a bein 
 to have power to operate, when it does u<^ 
 operate. Thus I may have power to walk, 
 when I sit ; or to speak, when I am silent. 
 Every operation, therefore, implies power ; 
 but the power does not imply the operation. 
 
 The faculties of the mind, and its powers, 
 are often used as synonymous expressions. 
 But, as most synonymcs have some minute 
 distinction that deserves notice, I apprehend 
 that the word /ac«% [15] is most properly 
 applied to those powers of the mind which 
 are original and natural, and which make a 
 part of the constitution of the mind. There 
 are other powers, which are acquired by 
 use, exercise, or study, which are not called 
 faculties, but habits. There must be some- 
 thing in the constitution of the mind neces- 
 sary to our being able to acquire habits 
 
 and this is commonly called capacity.' 
 
 4. We frequently meet with a distinction 
 in writers upon this subject, between things 
 in the mind, and things corlcrnul to the mind. 
 The powers, faculties, and operations of the 
 mind, are things in the mind. Everything 
 is said to be in the mind, of which the mind 
 is the subject. It is self-evident that there 
 are some things which cannot exist without 
 a subject to which they belong, and of which 
 tliey are attributes. Thus, colour must be 
 in something coloured ; figure in something 
 figured ; thought can only be in something 
 that thinks ; wisdom and virtue cannot exist 
 but in some being that is wise and virtuous. 
 When, therefore, we speak of things in the 
 mind, we understand by this, things of which 
 the mind is the subject. Excc[iting the 
 mind itself, and things in the mind, all other 
 things are said to be external. It ought 
 therefore to be remembered, that this dis- 
 tinction between things in the mind and 
 things external, is not meant to signify the 
 place of the things we speak of, but their 
 subject. -j- 
 
 There is a figurative sense in which things 
 are said to be in the mind, which it is suf- 
 ficient barely to mention. We say such a 
 thing was not in my mind ; meaning no more 
 than that I had not the least thought of it. 
 By a figure, we put thcthing for the thought 
 
 * Tho.iC terms properly stand in the followiiic; re 
 lations •.—I'oUH'rs are active iinil pnssiih\ nnliirut 
 ami acquired. I'owcrs, natural ar.daelive,.areralletl 
 t'aciilliis : I'owcrs, natural ai'il passive, r(;/).7i-iY/ij 
 or Ilcccptivilii s : I'owtrs aeijiiired arc llnlhts, .ind 
 habit 18 used both in anaetiveand in a pa^i-iveeense; 
 the Power, again, ol ae<|uirin>! a h.ibil, i.s called n 
 Disposition.— On the meanini,' ot the term I'ower, see 
 further, under the lirst Kssay on tho Active I'owers, 
 chap, iii , p •-':( — II 
 
 f Subject and (tijcct .ire correlative Icrmi. I'lic 
 former i* properly /(/ in i/i/u : liie laller, id ciicn 
 quod. Hence, in psycholdKicul lan^u.-ine, the juAy-c/, 
 absolutely, is the niiiiil Ihal knows or thinks— i <•., 
 the mind considireil as the subject ol knowledne or 
 tliuuijhl ; the til'jccl, that which is known, or tlioiij;lit 
 about. I'he .idjciiivi's sulijcftivr ntn\ ol'jcctivc are 
 convenient, il not indLviientable, expicssiuns.— II.
 
 222 
 
 ON THE INTELLECTUAL POWERS. 
 
 [^ESSAY I. 
 
 of it. In this sense external things are in 
 the mind as often as they are the objects of 
 our tliought. 
 
 5. Thinking is a very general word, which 
 includes all the operations of our minds, and 
 is so well understood as to need no defi- 
 nition.* [IG] 
 
 To percKive, to remember, to be conscious, 
 and to conceive or imagine, are words com- 
 mon to philosophers and to the vulgar. 
 They signify different operations of the 
 mind, which are distinguished in all lan- 
 guages, and by all men that think. I shall 
 endeavour to use them in their most com- 
 mon and proper acceptation, and I think 
 they are hardly capable of strict definition. 
 But, as some philosophers, in treating of the 
 mind, have taken the liberty to use them 
 very improperly, so as to corrupt the Eng- 
 lish language, and to confound things 
 which the common understanding of man- 
 kind hath always led them to distinguish, 
 I shall make some observations on the mean- 
 ing of them, that may prevent ambiguity 
 or confusion in the use of them. 
 
 G. First, We are never said to perceive 
 things, of the existence of which we have 
 not a full conviction. I may conceive or 
 imagine a mountain of gold, or a winged 
 horse ; but no man says that he perceives 
 such a creature of imagination. Thus per- 
 ception is distinguished from conception or 
 imagination. Secondly, Perception is ap- 
 plied only to external objects, not to those 
 that are in the mind itself. When I am 
 pained, I do not say that I perceive pain, 
 but that I feel it, or that I am conscious of 
 it. Thus, perception is distinguished from 
 consciousness. Thirdly, The immediate 
 object of perception must be something pre- 
 sent, and not what is past. We may re- 
 member what is past, but do not perceive 
 it. I may say, I perceive such a person 
 has had the small-pox ; but this phrase is 
 figurative, although the figure is so familiar 
 that it is not observed. The meaning of it 
 is, that I perceive the pits in his face, which 
 are certain signs of his having had the small 
 pox. We say we perceive the thing signi- 
 tied, when we only perceive the sign. But 
 when the word perception is used properly, 
 and without any figure, it is never applied 
 to things past. And thus it is distinguished 
 from remembrance. 
 
 In a woi'd, perception is most properly 
 applied to the evidence which we have of 
 external objects by our senses. But, as 
 this is a [17] very clear and cogent kind of 
 evidence, the word is often applied by ana- 
 logy to the evidence of reason or of testi- 
 
 • ThotightaxiA thinking are used in a more, and in 
 a less, restricted signification. In the former mean- 
 ing they are limited to the discursive energies alone ; 
 in the latter, they are co-extensive with conscious- 
 ness. — H. 
 
 [ 16-18"! 
 
 niony, when it is clear and cogent. The 
 perception of external objects by our senses, 
 is an operation of the mind of a peculiar 
 nature, and ought to have a name appro- 
 priated to it. It has so in all languages. 
 And, in English, I know no word more 
 proper to express this act of the mind than 
 perception. Seeing, hearing, smelling, 
 tasting, and touching or feeling, are words 
 that express the operations, proper to each 
 sense ; perceiving expresses that which is 
 common to them all. 
 
 The observations made on this word 
 would have been unnecessary, if it had not 
 been so much abused in philosophical 
 writings upon the mind ; for, in other writ- 
 ings, it nas no obscurity. Although this 
 abuse is not chargeable on Mr Hume only, 
 yet I think he has carried it to the highest 
 pitch. The first sentence of his " Treatise 
 of Hunian Nature" runs thus :-— " All the 
 perceptions of the human mind resolve 
 themselves into two distinct heads, which 
 I shall call impressions and ideas." He 
 adds, a little after, that, under the nam* 
 of impressions, he comprehends all our 
 sensations, passions, and emotions. Here 
 we learn that our passions and emotions 
 are perceptions. I beUeve, no English 
 writer before him ever gave the name of a 
 perception to any passion or emotion. 
 When a man is angry, we must say that he 
 has the perception of anger. When he is 
 in love, that he has the perception of love. 
 He speaks often of the perceptions of me- 
 mory, and of the perceptions of imagina- 
 tion ; and he might as well speak of the 
 hearing of sight, or of the smelling of touch ; 
 for, surely, hearing is not more different 
 from sight, or smelling from touch, than 
 perceiving is from remembering or imagin- 
 ing.* 
 
 7- Consciousness is a word used bv 
 philosophers, to signify that immediate 
 knowledge which we have of our present 
 thoughts and purposes, and, in general, of 
 all the present operations of our minds. 
 Whence we may observe, that conscious- 
 ness is only of things present. To apply 
 consciousness to things past, which some- 
 times [ 18] is done in popular discourse, is to 
 confound consciousness with memory ; and 
 all such confusion of words ought to be 
 avoided in philosophical discourse. It is 
 likewise to be observed, that consciousness 
 
 • In the Cartesian and Lockian philosophies, the 
 term Perception was used almost convertibly with 
 Consciousness : whatever we could be said to be 
 conscious of, that we could be said to perceive. And 
 there is nothing in the etymology of the word, or in 
 its use by ancient writers, that renders this unexclu. 
 sive application of it abusive. In the Leibnitzian 
 pliilosophy, perception and apperception were dis. 
 tinguished in a peculiar manner — of which again. 
 Reld IS right in his own restriction of the term; but 
 he is not warranted in blaming Humefor having used 
 it in the wider signification of his predecessors. — H.
 
 euAP. 1.3 
 
 EXPLICATION OF WORDS. 
 
 223 
 
 is only of things in the mind, and not of 
 external things. It is improper to say, I 
 am conscious of the table which is before 
 me. I perceive it, I see it ; but do not say 
 I am conscious of it. As that consciousness 
 by which we have a knowledge of the opera- 
 tions of our own minds, is a different power 
 from that by which we perceive external 
 objects, and as these different powers have 
 different names in our language, and, I 
 believe, in all languages, a philosopher 
 ought carefully to preserve this distinction, 
 and never to confound things so different in 
 their nature." 
 
 8. Conceiving, imagining, and appre- 
 hending, are commonly used as synony- 
 mous hi our language, and signify the same 
 thing which the logicians call simple appre- 
 hension. This is an operation of the mind 
 different from all tliose we have mentioned. 
 Whatever we perceive, whatever we re- 
 member, whatever we are conscious of, we 
 have a full persuasion or conviction of its 
 existence. But we may conceive or imagine 
 what has no existence, and what we firmly 
 believe to have no existence. What never 
 had an existence cannot be remembered ; 
 what has no existence at present cannot 
 be the object of perception or of conscious- 
 ness ; but what never had, nor has any 
 existence, may be conceived. Every man 
 knows that it is as easy to conceive a winged 
 horse, or a centaur, as it is to conceive ahorse 
 or a man. Let it be observed, therefore, that 
 to conceive, to imagine, to apprehend, when 
 taken in the proper sense, signify an act of 
 the mind which implies no belief or judg- 
 ment at all.+ It is an act of the mind by 
 which nothing is affirmed or denied, and 
 which, therefore, can neither be true nor 
 false. 
 
 But there is another and a very different 
 meaning of those words, so common and so 
 well authorized in language that it cannot 
 easily be avoided ; and on that account 
 we ought to be the more on our guard, that 
 we be not misled by the ambiguity. I'o- 
 ateness and [19] good-breeding lead men, on 
 most occasions, to express their opinions 
 with modesty, especially when they differ 
 from others whom they ought to respect. 
 Therefore, when we would express our 
 opinion modestly, instead of saying, " This 
 ismyopinion," or, "This is my judgment," 
 which has the air of dogmaticalness, we say, 
 "I conceive it to be thus. — I imagine, or ap- 
 prehend it to be thus ;" which is understood 
 aa a modest declaration of our judgmcnt- 
 In like manner, when anything is said which 
 we take to be impossible, we say, " We can- 
 
 • Heid's degradation of Consciousncis into n 
 ipccial faculty, (in which he teems to follow Hut- 
 cheion, in opiiositioii to other |>hiluio|ihers,] is, in 
 every iKjint of view, obfioxioua to cver7 possible ob- 
 jection. .See note II. — H 
 
 t Except of its own ideal reality. — H. 
 
 [ly, 20 1 
 
 not conceive it ;" meaiung that we cannot 
 believe it. 
 
 Thus we see that the words conceive, 
 imagine, apprehend, have two meanings, 
 and are used to express two operations of 
 the mind, which ought never to be con- 
 founded. Sometimes they express simple 
 apprehension, which implies no judgment 
 at all ; sometimes they express judgment or 
 opinion. This ambiguity ought to be at- 
 tended to, that we may not impose upon 
 ourselves or others in the use of tliem. The 
 ambiguity is indeed remedied, in a great 
 measure, by their construction. When 
 they are used to express simple apprehcn« 
 sion, they are followed by a noun in the 
 accusative case, which signifies the object 
 conceived ; but, when they are used to ex- 
 press opinion or judgment, they are com- 
 monly followed by a verb, in the infinitive 
 mood. " I conceive an Egyptian pyramid." 
 This implies no judgment. " I conceive 
 the Egyptian pyramids to be the most an- 
 cient monuments of human art." This 
 imphes judgment. When the words are 
 used in the last sense, the thing conceived 
 must be a proposition, because judgment 
 cannot be expressed but by a proposition. 
 When they are used in the first sense, the 
 thing conceived may be no proposition, but 
 a simple term only — as a pyramid, an obe- 
 lisk. Yet it may be observed, that even a 
 proposition may be simply apprehended, 
 without forming any judgment of its truth 
 or falsehood : for it is one thing to conceive 
 the meaning of a proposition ; it is another 
 thing to judge it to bo true or false. [20] 
 
 Although the distinction between simple 
 apprehension, and every degree of assent or 
 judgment, be perfectly evident to every man 
 who reflects attentively on what passes in 
 his own mind — although it is very neces- 
 sary, in treatuig of the powers of the mind, 
 to attend carefully to this distinction — yet, 
 in the afl'airs of common life, it is seldom 
 necessary to observe it accurately. On 
 this account we shall iii^, in all conmion 
 languages, the words whWh express one of 
 those operations frequently applied to the 
 other. To think, to sujipose, to imagine, 
 to conceive, to apprehend, are the words wc 
 use to express simple ajiprehension ; but 
 they are all frequently used to express 
 judgment. Tiieir ambiguity seldom occa- 
 sions any inconvenience in tlie connnon 
 aflairs of life, for which language is franif d. 
 But it has perplexed jjliilosophcrs, in treat- 
 ing of the oi)eratii)ns of the mind, and will 
 always jierplex tliem, if tlioy do not attend 
 accurately to the ditlorent meanings which 
 are put upon tiiose words <in (litren.'nt oc- 
 casions. 
 
 9. Most of the ojjcrations of tlio mind, 
 from their very nature, nmst have objecta 
 to which tlicv are directed, and about which
 
 224 
 
 ON THE INTELLECTUAL POWERS. 
 
 [essay 
 
 they are employed. Ilo tliat perceives, 
 must perceive something ; and that which 
 he perceives is called the object of his per- 
 ception. To perceive, without having any 
 object of perception, is impossible. The 
 mind that perceives, the object perceived, 
 und the npcralion of perceiving that object, 
 are distinct things, and are distinguished in 
 the structure of all languages. In this 
 sentence, " I see, or perceive the moon," 
 / is the person or mind, the active verb 
 see denotes the operation of that mind, and 
 the moon denotes the object. What we 
 have said of perceiving, is equally applicable 
 to most operations of tlie mind. Such opera- 
 tions are, in all languages, expressed by 
 active transitive verbs ; and we know that, 
 in all languages, such verbs require a thing 
 or person, which is the agent, and a noun 
 following in an oblique case, which is the 
 object. Whence it is evident, that all 
 mankind, both those who have contrived 
 language, and those who use it ^vitli under- 
 standing, have distinguished these three 
 things as different— to wit, the operations of 
 themind, which [21] areexpressed byactive 
 verbs ; the mind itself, which is the nomin- 
 ative to those verbs; and the object, which 
 is, in the oblique case, governed by them. 
 
 It would have been unnecessary to ex- 
 ))lain so obvious a distinction, if some sys- 
 tems of philosophy had not confounded it. 
 Mr Hume's system, in particular, confounds 
 all distinction between the operations of the 
 mind and their objects. When he speaks 
 of the ideas of memory, the ideas of imagin- 
 ation, and the ideas of sense, it is often im- 
 possible, from the tenor of his discourse, to 
 know whether, by those ideas, he means 
 the operations of the mind, or the objects 
 about which they are employed. And, 
 indeed, according to his system, there is 
 no distinction between the one and the 
 other. 
 
 A philosopher is, no doubt, entitled to 
 examine even those distinctions that are to 
 be found in the structure of all languages ; 
 and, if he is able to shew that there is no 
 foundation for them in the nature of the 
 thmgs distinguished — if he can point out 
 some prejudice common to mankind which 
 has led them to distinguish things that are 
 not really different — in that case, such a 
 distinction may be imputed to a vulgar 
 error, which ought to be corrected in philo- 
 sophy. But when, in his first setting out, 
 he takes it for granted, without proof, that 
 distinctions found in the structure of all 
 languages, have no foundation in nature, 
 this, surely, is too fastidious a way of 
 treating the common sense of mankind. 
 When we come to be instructed by philo- 
 sophers, we must bring the old light of 
 common sense along with us, and by it 
 judge of the new light which the philo- 
 '['21 23] 
 
 sopher communicates to ua. But when we 
 are required to put out the old light alto- 
 gether, that we may follow the new, we 
 have reason to be on our guard. There 
 may be distinctions that have a real foun- 
 dation, and which may be necessary in 
 philosophy, which are not made in common 
 language, because not necessary in the com- 
 mon business of life. But I believe [22] no 
 instance will be found of a distinction made 
 in all languages, which has not a just found- 
 ation in nature. 
 
 10. The word idea* occurs so frequently 
 in modern philosophical Avritings upon the 
 mind, and is so ambiguous in its meaning, 
 that it is~iiccessary to make some observa- 
 tions upon it. There are chiefly two mean- 
 ings of this word in modern authors— a 
 po}iular and a philosophical. 
 
 First, In popular language, idea signi- 
 fies the same thing as conception, appre- 
 hension, notion. To have an idea of any- 
 thing, is to conceive it. To have a distinct 
 idea, is to conceive it distinctly. To have 
 no idea of it, is not to conceive it at all. 
 It was before observed, that conceiving or 
 apprehending has always been considered 
 l>y all men as an act or operation of the 
 mind, and, on that account, has been ex- 
 pressed in all languages by an active verb. 
 When, therefore, we use the phrase of 
 having ideas, in the popular sense, we 
 ought to attend to this, that it signifies 
 precisely the same thing which we com- 
 monly express by the active verbs, conceiv- 
 ing or apprehending. 
 
 When the word idea is taken in thi? po- 
 pular sense, no man can possibly doubt 
 whether he has ideas. For he that doubts 
 must think, and to think is to have ideas. 
 
 Sometimes, in popular language, a man's 
 ideas signify his opinions. The ideas of 
 Aristotle, or of Epicurus, signify the 
 opinions of these philosophers. What was 
 formerly said of the words imagine, conceive, 
 apprehend, that they are sometimes used 
 to express judgment, is no less true of the 
 word idea. This signification of the word 
 seems indeed more common in the French 
 language than in English. But it is found 
 in this sense in good English authors, and 
 even in JMr Locke. Thus we see, that 
 having ideas, taken in the popular sense, 
 has precisely the same meaning with conceiv- 
 ing, imagining, apprehending, and has like- 
 wise [23 j the same ambiguity. It may, there- 
 fore, be doubted, whether the introduction of 
 this word into popular discourse, to signify the 
 operation of conceiving or apprehending, 
 was at all necessary. For, first, We have, 
 as has been shewn, several words which are 
 either originally English, or have been long 
 naturalized, that express the same thing ; 
 
 * Oi! l!ic history of the term Idea, see Note G.— 11.
 
 CHAP. 
 
 I.] 
 
 EXPLICATION OF WORDS. 
 
 2-25 
 
 why, therefore, should we adopt a Greek 
 word, in place of these, any more than a 
 French or a German word ? Besides, the 
 words of our own language are less ambi- 
 guous. For the word idea has, for many 
 ages, been used by philosophers as a term 
 of art ; and in the different systems of phi- 
 losophers means very different things. 
 
 Secondly, According to the philosophi- 
 cal meaning of the word idea, it does not 
 signify that act of the mind which we call 
 thought or conception, but some object of 
 thought. Ideas, accordiug to Mr Locke, 
 (^\ hose very frequent use of this word has 
 probably been the occasion of its being 
 adopted into common language,) " are 
 nothing but the immediate objects of the 
 mind in thinking." But of those objects of 
 thought called ideas, different sects of phi- 
 losophers have given a very different ac- 
 count. Bruckerus, a learned German,'wrote 
 a whole book, giving the history of ideas. 
 
 The most ancient system we have con- 
 cerning ideas, is that which is explained in 
 several dialogues of Plato, and which many 
 ancient, as well as n;oderu writers, have 
 ascribed to Plato, as the inventor. But it is 
 certain that Plato had his doctrine upon 
 this subject, as well as the name i'lea, from 
 the school of Pythagoras. We have still 
 extant, a tract of Timieus, the Locrian, a 
 Pythagorean philosopher, concerning the 
 soul of the world, in which we find the sub- 
 stance of Plato's doctrine concerning ideas.* 
 They were held to be eternal, uncreated, 
 and immutable forms, or models, according 
 to which the Deity made every species of 
 things that exists, of an eternal matter. 
 Those philosophers held, that there are 
 three first principles of all things: F'usl, 
 An eternal matter, of which all tilings were 
 made ; Second/i/, Eternal and immaterial 
 forms, or ideas, according to whichthcy were 
 made; and, [24] T/iirrlly, AnefWcicnt L-.iuse, 
 the Deity who made theni.-|- The mind of 
 man, in order to its being fitted for the con- 
 templation of these eternal ideas, must un- 
 dergo a certain purification, and be weaned 
 from sensible things. Tlie eternal ideas arc 
 the only oljject of science ; because the ob- 
 jectsof sense, being in a perpetual flux, there 
 canbeno real knowledge with regard to thcin. 
 
 The philosophers of the Alexandrian 
 school, commonly called llic latter Plalo- 
 nisls, made some change upon the system of 
 the ancient Platonists with respect to the 
 eternal ideas. They held them not to be a 
 princijile distinct from the Deity, but to be 
 tlie conceptions of things in the divine un- 
 
 ♦ The whole series of Pythagorean treatises and 
 fragments in the Doric clialcc, in which the di)C- 
 trirjou and (jhra'fc'olopy (if I'lato-anil Aristotle an' so 
 marvellounly anticipated, are now iirovtd to l)e coni- 
 parativtly recent I'lrgerics. Of ihese, the treatise 
 under the name of I'im.rus, is one. — \i. 
 
 \ .See aiiove, p- '^Ut, a, note ' — II. 
 
 [24, 2.5] 
 
 derstanding ;tlie natures and essences of all 
 things being perfectly known to him from 
 eternity. 
 
 It ought to be observed that the Pythago- 
 reans, and the Platonists, whether elder or 
 latter, made the eternal'ideas to be objects 
 of science only, and of abstract contempla- 
 tion, not the objects of sense.* And in 
 this, the ancient system of eternal ideas 
 differs from the modern one of Father Ma- 
 lebranche. He held, in common with other 
 modern philosophers, that no external 
 thing is perceived by us immediately, but 
 only by ideas. But he thought that the 
 ideas, by which we perceive an external 
 world, are the ideas of the Deity himself, 
 in whose mind the ideas of all things, past, 
 present, and future, must have been from 
 eternity; for the Deity being intimately 
 present to our minds at all times, may dis- 
 cover to us as much of his ideas as he sees 
 proper, according to certain established 
 laws of nature ; and in his ideas, as in a 
 mirror, w^e perceive whatever we do per- 
 ceive of the external world. 
 
 Thus we have three systems, which main- 
 tain that the ideas which are the imme- 
 diate objects of human knowledge, are 
 eternal and immutable, and existed before 
 the things which they represent. There 
 are other systems, accordiug to which the 
 ideas which are the immediate objects of 
 all our thoughts, are posterior to the things 
 which they represent, and derived from 
 them. We shall [25] give some account of 
 these ; but, as they have gradually sprung 
 out of the ancient Peripatetic system, it is 
 necessary to begin with some account of it. 
 
 Aristotle taught that all the objects of 
 our thought enter at first by the senses ; 
 and, since the sense cannot receive external 
 material objects themselves, it receives their 
 species — that is, their images or forms, 
 without the matter; as wax receives tlie form 
 of the seal without any of the matter c)f it. 
 These images or forms, impressed upon the 
 senses, are called sen.sVile species, and are 
 the objects only of the sensitive jiart of the 
 mind ; but, by various internal powers, they 
 are retained, refined, and spiritualized, so as 
 to become objects of memory and imagina- 
 tion, and, at last, of pure intellection. 
 When they are objects of memory and of 
 imagination, they get the name(>f/)/*aw/rtA'»is. 
 When, by farther refinement, and being 
 stripped of their particularities, tliey become 
 ol)jects of science, they are called intclli- 
 H'lble species : so that every inunediato 
 
 « Roid, in common with onr philosophers In general, 
 had no knowledge i-f the Platonic theory of scnsihU 
 percr.iliini; and yet tbc gnostic Joiins, the cnfiniliiif 
 rt'iisiiiis of the Platonists, held afar more proximate 
 relation ti> idcaf in the modern acceptation, than the 
 Plaion c idi'as themselves. 'Jhesr, in fact, n« to all 
 that relates to tlie '(jcirineof pcrccpilnn und ima. 
 ginalinn, may he thrown wli.lly i nt of .-iccoinit. Se» 
 l)( low.iitider \>, IIH. — II.
 
 2-26 
 
 ON THE INTELLECTUAL POWERS. 
 
 [essay I. 
 
 object, whether of sense, of memory, of 
 imagination, or of reasoning, must be some 
 phantasm or species in the mind itself.* 
 
 The followers of Aristotle, especially the 
 schoolmen, made great additicjns to this 
 theory, which the author himself mentions 
 very briefly, and with an appearance of 
 reserve. They entered into large disquisi- 
 tions with regard to the sensible species : 
 what kind of things they are ; how they 
 are sent forth by the object, and enter by 
 the organs of the senses ; how they are 
 preserved and refined by various agents, 
 called internal senses, concerning the num- 
 ber and offices of which they had many 
 controversies. But we shall not enter into 
 a detail of these matters. 
 
 The reason of giving this brief account of 
 the theory of the Peripatetics, with regard to 
 the immediate objects of our thoughts, is, 
 because the doctrine of modern philoso- 
 phers concerning ideas is built upon it. Mr 
 Locke, who uses this word so very fre- 
 quently, tells us, that he means the same thing 
 by it as is commonly [26] meant by species 
 or phantasm. Gassendi, from whom Locke 
 borrowed more than from any other author, 
 says the same. The words species and 
 phantasm, are terms of art in the Peripa- 
 tetic system, and the meaning of them is to 
 be learned from it.-|- 
 
 The theory of Democritus and Epicurus, 
 on this subject, was not very unlike to that 
 of the Peripatetics. They held that all 
 bodies continually send forth slender films 
 or spectres from their surface, of such 
 extreme subtilty that they easily penetrate 
 our gross bodies, or enter by the organs of 
 sense, and stamp their image upon the 
 mind. The sensible species of Aristotle 
 were mere forms without matter. The 
 spectres of Epicurus were composed of a 
 very subtile matter. 
 
 Modern philosophers, as well as the Peri- 
 patetics and Epicureans of old, have con- 
 ceived that external objects cannot be the 
 immediate objects of our thought ; that 
 there must be some image of them m the 
 mind itself, in which, as in a mirror, they 
 are seen. And the name idea, in the philo- 
 sophical sense of it, is given to those inter- 
 nal and immediate objects of our thoughts. 
 The external thing is the remote or mediate 
 object ; but the idea, or image of that object 
 in the mind, is the immediate object, without 
 
 • This is a tolerable account of the doctrine 
 vulgarly attributed to Aristotle. — H. 
 
 ■^ If by this it be meant that the terms of species 
 and phantasm, as occasionally employed by Gassendi 
 and lx)cl<e, are used by them in the common mean- 
 ing attache! to them in the Schools, Reid is wrong. 
 Gassendi, no more than Des Cartes, In adopting 
 these terms of the Heripatetics, adopted them in 
 their Peripatetic signification. Both these philoso- 
 piiers are explicit in declaring the contrary ; and 
 what the-e term^ as employed by them denote, they 
 have cl arly St ted. l.ocke is less precise.— U. 
 
 which we could have no perception, no re- 
 membrance, no conception of the mediate 
 object.* 
 
 When, therefore, in common language, 
 we speak of having an idea of anything, we 
 mean no more by that expression, but 
 thinking of it. The vulgar allow that this 
 expression implies a mind that thinks, an 
 act of that mind which we call thinking, 
 and an object about which we think. But, 
 besides these three, the philosopher con- 
 ceives that there is a fourth — to wit, the 
 idea, which is the immediate object. The 
 idea is in the mind itself, and can have no 
 existence but in a mind that thinks ; but the 
 remote or mediate object may be something 
 external, as the sun or moon ; it may be 
 something past or future ; it may be some- 
 thing which never existed. [27] This is 
 the philosophical meaning of the word idea ; 
 and we may observe that this meaning of 
 that word is built upon a philosophical 
 opinion : for, if philosophers had not be- 
 lieved that there are such immediate objects 
 of all our thoughts in the mind, they would 
 never have used the word idea to express 
 them. 
 
 I shall only add, on this article, that, al- 
 though I may have occasion to use the word 
 idea in this philosophical sense in explaining 
 the opinions of others, I shall have no occa- 
 sion to use it in expressing my own, because 
 I believe ideas, taken in this sense, to be 
 a mere fiction of philosophers. And, in the 
 popular meaning of the word, there is the 
 less occasion to use it, because the English 
 words thought, notion, apprehension, answer 
 the purpose as well as the Greek word 
 idea; with this advantage, that they are 
 less ambiguous. There is, indeed, a mean- 
 ing of the word idea, which I think most 
 agreeable to its use in ancient philosophy, 
 and which I would willingly adopt, if use, 
 the arbiter of language, did permit. But 
 this will come to be explained afterwards. 
 
 IL The word impression is used by Mr 
 Hume, in speaking of the operations of the 
 mind, almost as often as the word idea is 
 by Mr Locke. What the latter calls ideas, 
 the former divides into two classes ; one of 
 which he calls impressions, the other ideas. 
 I shall make some observations upon Mr 
 Hume's explication of that word, and then 
 consider the proper meaning of it in the 
 English language. 
 
 " We may divide," (says Mr Hume, 
 " Essays," vol. II., p. 18,t) " all the percep- 
 tions of the human mind into two classes 
 or species, which are distinguished by their 
 
 » On Reid's ambiguous employment of the ex. 
 pressioDS mediite and immtdinie olijcct, see Note 
 15 ; and, on nis confusion of the two hypotheses of 
 representation, Note C — H. 
 
 t " Enquiry concerning Human Understanding," 
 4 2. The quotation has been filled up by the origi. 
 nal. — H. 
 
 [26, 271
 
 CHAP. 
 
 ••J 
 
 EXPLICATION OF WORDS. 
 
 227 
 
 different degrees of force and vivacity. The 
 less lively and forcible are commonly deno- 
 minated THOUGHTS or IDEAS. The other 
 species want a name in our language, and 
 in most others ; [I suppose because it was 
 not requisite for any but pliilosophical pur- 
 poses to rank them under a general term 
 or appellation.] Let us, therefore, use a 
 little freedom, and call them impressions ; 
 [employing that word in a sense somewhat 
 difterent from the usual.] By the term 
 impression, then, I mean all our more lively 
 perceptions, when we hear, or see, or feel, 
 or love, or hate, or desire, or will. [And 
 impressions are distinguished from] ideas 
 [which] are the [28] less lively perceptions, 
 of which we are conscious, when we reflect on 
 any of those sensations or movements above 
 mentioned." 
 
 This is the explication Mr Hume hath 
 given in his " Essays" of the term impres- 
 .s to ;i5, when applied to the mind: and his 
 explication of it, in his " Treatise of Human 
 Nature," is to the same purpose. [Vol. I. 
 p. 11.] 
 
 Disputes about words belong rather to 
 grammarians than to philosophers ; but 
 philosophers ought not to escape censure 
 when they corrupt a language, by using 
 words in a way which the purity of the lan- 
 guage will not admit. I find fault with Mr 
 Hume's phraseology in the words I have 
 quoted — 
 
 First, Because he gives the name of per- 
 ceptions to every operation of the mind. 
 Love is a perception, hatred a perception ; 
 desire is a perception, will is a perception ; 
 and, by the same rule, a doubt, a question, 
 a command, is a perception. This is an 
 intolerable abuse of language, which no phi- 
 losopher has authority to introduce." 
 
 Secondli/, "When Mr Hume says, that we 
 may diride all ihe perceptions of the human 
 mind into two classes nr species, which arc 
 distinguished liij their degrees of force and 
 vivacity, the manner of expression is loose 
 and unphilosophical. To differ in species 
 is one thing ; to differ in degree is an- 
 other. Things which differ in degree only 
 must be of the same species. It is a 
 maxim of common sense, admitted by all 
 men, that greater and less do not make 
 a change of species. -j- The same man 
 may differ in the degree of his force and 
 vivacity, in the morning and at night, in 
 health and in sickness ; but this is so far 
 from making him a different species, that 
 it docs not so much as make him a dif- 
 ferent individual. To say, therefore, that 
 two different classes, or species of percep- 
 
 • Hume (lid not intrnduce it The term I'creep- 
 Hon WM ao used by Den C.irie«an<l many ntlic-rs ; and, 
 a»dcslrei, feelings, ^c. exU( nnly askiKiwn.soaretliey 
 all, in a certain r(ntie,coKnitionB (|Hrceptioni.)— H. 
 
 + " Magl« et ininui non variant npcciem." — II. 
 
 yS, 29 1 
 
 tions, are distinguished by the degrees of 
 their force and vivacity, is to confound a 
 difference of degree with a difference of 
 species, which every man of understanding 
 knows how to distinguish.* [29] 
 
 Thirdly, We may observe, that this 
 author, having given the general name of 
 perception to all the operations of the 
 mind,"!- and distinguished them into two 
 classes or species, which differ only in de- 
 gree of force and vivacity, tells us, that he 
 gives the name of impressions to all our 
 more lively perceptions — to wit, when we 
 hear, or see, or feel, or love, or hate, or 
 desire, or wUl. There is great confiision 
 in this account of the meaning of the word 
 impression. When I see, this is an im- 
 pressivTi. But why has not the author 
 told us whether he gives the name of im- 
 pressiun to the object seen, or to that act of 
 my mind by which I see it ? When I see 
 the full moon, the full moon is one thing, 
 my perceiving it is another thing. Which 
 of these two things docs he call an impres- 
 sion ? We are left to guess this ; nor does 
 all that this author writes about impressions 
 clear this point. Everjiihing he says tends 
 to darken it, and to lead us to think that the 
 full moon which I see, and my seeing it, are 
 not two things, but one and the same thing.* 
 
 The same observation may be applied to 
 every other instance the author gives to 
 illustrate the meaning of the word impres- 
 sion. " AVhen we hear, when we feel, 
 when we love, when we hate, when we de- 
 sire, when we will." In all these acts of 
 the mind there must be an object, which is 
 heard, or felt, or loved, or hated, or desired, 
 or willed. Thus, for instance, I love my 
 country. This, says IMr Hume, is an im- 
 pression. But what is the impression ? Is it 
 my country, or is it tlie affection I bear to it ? 
 I ask the philosopher this question ; but I 
 find no answer to it. And when I read all 
 
 • This objection reaches far more extensively than 
 to Hume ; in fnct, to all who do not allow an imme- 
 diate kiiowle 'ge or consciousness of the von. ego \n 
 ptrccpllon. Where are the philosophers who lo?— 
 Aristotle and Hobbes call imagination a dying sense; 
 and Des Cartes is equally exnlicit.— H. 
 
 t As others previously had done. — H. 
 
 X This objection is c:isily answerid. The thing, 
 (Hume would say,) as unknown, as unperceived, as 
 beycnd the sp/iere of nu/ consciousness, is to me as 
 zero ; to that, therclbrc, I could not refer, Aeper. 
 ceivrd, as known, it nui ! le vittiin l/ic splicre oj my 
 consciousness; hut, as plnloHopherscoiK ur in main- 
 taining that 1 can only be conscious of my nund and 
 its contents, the object, as perceived, muft be either 
 a mode of, or something contained within my mind, 
 and to that inlci-nnlul>jecl, as perceived, I give the 
 name of i>«;»<-.isio7i.— Nor can the act ol perception 
 (he would add) be really disliiguished Irom Ihccili. 
 Ject perceived. Both are only relatives, mutually 
 constituent of the same indivi ihle relaticm ol know, 
 ledge : an<l to that relation and thisc relatives I give 
 the name of impression, precisely as, in dillereiil 
 iioints of view, the term perception i- applieil to i he 
 mind perceiving, to the obj.ct i.erceived, and to t he 
 net of which these are Ihe ii teimral.le constituenti. 
 — 1 his likewise has reference In what follows.— H. 
 
 r
 
 228 
 
 ON>THE INTELLECTUAL POWERS. 
 
 [essay /. 
 
 that he has written ou this subject, I find 
 this word impression sometimes used to sig- 
 nify an operation of the mind, sometimes 
 the object of the operation ; but, for the 
 most part, it is a vague and indetermined 
 word that signifies both, 
 
 I know not whether it may be considered 
 as an apology for such abuse of words, in an 
 author who understood the language so well, 
 and used it with so great propriety in writ- 
 ing on other subjects, [30] that Mr Hume's 
 system, with regard to tlie mind, required a 
 language of a different structure from the 
 common : or, if expressed in plain English, 
 would have been too shocking to the com- 
 mon sense of mankind. To give an instance 
 or two of this. If a man receives a present 
 on which he puts a high value, if he see 
 and handle it, and put it in his pocket, this, 
 says Mr Hume, is an impression. If the 
 man only dream that he received such a 
 present, this is an idea. Wherein lies the 
 difference between this impression and this 
 idea — between the dream and the reality ? 
 They are different classes or species, says 
 Mr Hume : so far all men will agree with 
 him. But he adds, that they are distinguished 
 only by different degrees of force and viva- 
 city. Here he insinuates a tenet of his 
 own, in contradiction to the commonsense 
 of mankind. Common sense convinces every 
 man, that a lively dream is no nearer to a 
 reality than a faint one ; and that, if a man 
 should dream that he had all the wealth of 
 Croesus, it would not put one farthing in 
 his pocket. It is impossible to fabricate ar- 
 guments against such undeniable principles, 
 without confounding the meaning of words. 
 
 In like manner, if a man would persuade 
 me that the moon which I see, and my see- 
 ing it, are not two things, but one and the 
 same thing, he will answer his purpose less 
 by arguing this point in plain English, than 
 by confounding the two under one name — 
 such as that of an impression. For such is 
 the power of words, that, if we can be 
 brought to the habit of calling two things 
 that are connected by the same name, we are 
 the more easily led to believe them to be 
 one and the same thinsr. 
 
 Let us next consider the proper meaning 
 of the word impression* in English, that we 
 may see how far it is fit to express either 
 the operations of the mind or their objects. 
 
 When a figure is stamped upon a body by 
 pressure, that figure is called an impression, 
 as the impression of a seal on wax, of [31] 
 printing-types, or of a copperplate on paper- 
 This seems now to be the literal sense of 
 the word ; the effect borrowing its name 
 from the cause. But, by metaphor or ana- 
 logy, like most other words, its meaning is 
 extended, so as to signify any change pro- 
 
 * See below, unilerp 3;s.— H. 
 
 duced in a body by the operation of some 
 external cause. A blow of the hand makes 
 no impression on a stone wall ; but a bat- 
 tery of cannon may. The moon raises a 
 tide in the ocean, but makes no impression 
 on rivers and lakes. 
 
 When we speak of making an impression 
 on the mind, the word is carried still farther 
 from its literal meaning ; use, however, 
 which is the arbiter of language, authorizes 
 this application of it — as when we say that 
 admonition and reproof make little impres- 
 sion on those who are confirmed in bad 
 habits. The same discourse delivered in 
 one way makes a strong impression on the 
 hearers ; delivered in another way, it makes 
 no impression at all. 
 
 It may be observed that, in such ex- 
 amples, an impression made on the mind 
 always implies some change of purpose or 
 will ; some new habit produced, or some 
 former habit weakened ; some passion raised 
 or allayed. When such changes are pro- 
 duced by persuasion, example, or any ex- 
 ternal cause, we say that such causes make 
 an impression upon the mind ; but, when 
 things are seen, or heard, or apprehended, 
 without producing any passion or emotion, 
 we say that they make no impression. 
 
 In the most extensive sense, an impres- 
 sion is a change produced in some passive 
 subject by the operation of an external 
 cause, if we suppose an active being to 
 produce any change in itself by its own 
 active power, this is never called an im- 
 pression. It is the act or operation of 
 the being itself, not an impression upon it. 
 From this it appears, that to give the name 
 of an impression to any effect produced in 
 the mind, is to suppose that the mind does 
 not act at all in the production of that effect. 
 If seemg, heai'ing, desiring, willing, be 
 operations of the mind, they cannot be im- 
 pressions. If [32] they be impressions, they 
 cannot be operations of the mind. In the 
 structure of all languages, they are con- 
 sidered as acts or operations of the mind it- 
 self, and the names given them imply this. 
 To call them impressions, therefore, is to 
 trespass against the structure, not of a par- 
 ticular language only, but of all languages.* 
 
 If the word impression be an improper 
 word to signify the operations of the mind, 
 it is at least as unproper to signify their 
 objects ; for would any man be thought to 
 speak with propriety, who should say that 
 the sun is an impression, that the earth and 
 the sea are impressions ? 
 
 It is commonly believed, and taken for 
 granted, that every language, if '\t be suffi- 
 ciently copious in words, is equally fit to 
 express all opinions, whether they be true 
 
 * But see Scaligcr, " De Siibtiliute," Exerc. 298, 
 
 [30-32] 
 
 I
 
 CHAP. I.] 
 
 EXPLICATION OF >VORDS. 
 
 229 
 
 or false. I apprehend, however, that there 
 is an exception to this general rule, which 
 deserves our notice. There are certain 
 common opinions of mankind, upon which 
 the structure and grammar of all languages 
 are founded. While these opinions are 
 common to all men, there will be a great 
 similarity in all languages that are to be 
 found on the face of the earth. Such a 
 similarity there really is ; for we find in all 
 languages the same parts of speech, the 
 distinction of nouns and verbs, the distinc- 
 tion of nouns into adjective and substan- 
 tive, of verbs into active and passive. In 
 verbs we find like tenses, moods, persons, 
 and numbers. There are general rules of 
 grammar, the same in all languages. This 
 similarity of structure in all languages, 
 shews an uniformity among men in those 
 opinions upon which the structure of lan- 
 guage is founded. 
 
 If, for instance, we should suppose that 
 there was a nation who believed that the 
 things which we call attributes might exist 
 without a subject, there would be in their 
 language no distinction between adjectives 
 and substantives, nor would it be a rule 
 with them that an adjective has no mean- 
 ing, unless when joined to a substantive. 
 If there was any nation who did not dis- 
 tinguish bet ween [33] acting and being acted 
 upon, there would in their language be no 
 distinction between active and passive 
 verbs ; nor would it be a rule that the 
 active verb must have an agent in the 
 nominative case, but that, in the passive 
 verb, the agent must be in an oblique case. 
 
 Thestructure of all languages is grounded 
 upon common notions, which Mr Hume's 
 philosophy opposes, and endeavours to 
 overturn. Tliis, no doubt, led him to warji 
 the common language into a conformity with 
 his princii>les ; but we ought not to imitate 
 him in this, until we are satisfied that his 
 principles are Ijuilt on a solid foundation. 
 
 12. Sensation is a name given by philo- 
 .sophers to an act of mind, which may be 
 distinguished From all others l)y this, tliat 
 it hath no object distinct from the act itself.* 
 Pain of every kind is an uneasy sensation. 
 When I am pained, I cannot say that the 
 pain I feel is one thing, and that my feeling 
 it is another thing. They are one and the 
 same thing, and cannot be disjoined, even 
 in imagination. Pain, when it is not felt, 
 has no existence. It can be neither greater 
 nor less in degree or duration, nor anything 
 else in kind tlian it is felt to be. It cannot 
 exist by itself, nor in any suliject but in a 
 sentient being. No quality of an inanimate 
 
 • But seniation, in the laiiBuago of pliilosoplicri, 
 ha» been gcnoralh cmplnycd to ikiiotrllic whole pro- 
 ecu of seimitive.cognitiiiii, including bolli perci'plioii 
 proper awA fentntmn proper. On tliii (iistiinlion, 
 «cc below, l?"8sav II, > cli. xvi., and Ncic I) * — H. 
 
 [.S3, .31] 
 
 insentient being can have the least resem- 
 blance to it. 
 
 What we have said of pain may be 
 applied to every other sensation. Some of 
 them are agreeable, others uneasy, in 
 various degrees. These being objects of 
 desire or aversion, have some attention 
 given to them ; but many are indifl'erent, 
 and so little attended to that they have no 
 name in any language. 
 
 JMost operations of the mind that have 
 names in common language, are complex 
 in their nature, and made up of various 
 ingredients, or more simple acts ; which, 
 though conjoined in our constitution, must 
 be disjoined by abstraction, in order to our 
 having a distinct and scientific notion of the 
 complex operation- [34] In such operations, 
 sensation, for the most part, makes an in- 
 gredient. Tliose who do not attend to the 
 complex nature of such operations, are apt 
 to resolve them into some one of the simple 
 acts of which they are compounded, over- 
 looking the others. And from this cause 
 many disputes have been raised, and many 
 errors have been occasioned with regard to 
 the nature of such operations. 
 
 The perception of external objects ia 
 accompanied with some sensation corre- 
 sponding to the object perceived, and such 
 sensations have, in many cases, in all lan- 
 guages, the same name with the external 
 object which they always accompany. The 
 difficulty of disjoining, by abstraction, things 
 thus constantly conjoined in the course of 
 nature, and things which have one and the 
 same name in all languages, has likewise 
 been frequently an occasion of errors in the 
 philosophy of the mind. To avoid such 
 errors, nothing is of more importance than 
 to have a distinct notion of that simi)le 
 act of the mind which we call sensation, and 
 which we have endeavoured to describe. 
 By this means, we shall find it more easy to 
 distinguish it from every external ol)joct that 
 it ac<r(iin])anies, and from every other act of 
 the mind that may be conjoined with it. 
 For this purpose, it is likewise of import- 
 ance that the name of sensation should, in 
 pliik>sophical writings, be appropriated to 
 signify this simi)le act of the mind, wiihout 
 including anything more in its signification, 
 or being applied to other ])urposes. 
 
 I shall add an observation concerning the 
 word frdiiifi. This word lias two meanings. 
 First, it signifies tlie i)erci'pti(jns we have of 
 external objects, by the sense of touch. 
 When we speak of feeling a body to be hard 
 or soft, rough or smooth, hot or cold, to 
 feel these things is to ])erc(ive them by 
 touch. They are external things, and tliat 
 act of the niind by whicli we feel them is 
 easily (listingnisliivl from the objfcts felt. 
 Sciondlji, till! word fcflinr/ is wh'i\ to signify 
 the same thing as fcnsnlii'ii. which we liavo
 
 230 
 
 ON THE INTELLECTUAL POWERS. 
 
 [essay I. 
 
 just now explained ; and, in this sense, it 
 has no object ; the feeling and the thing 
 felt are one and the same. [35j 
 
 Perhaps betwixt feeling, taken in this 
 last sense, and sensation, thei-e may be this 
 small difference, that sensation is most com- 
 monly used to signify those feelings which 
 we have by our external senses and bodily 
 appetites, and all our bodily pains and 
 pleasures. But there are feelings of a 
 nobler nature accompanying our affections, 
 our moral judgments, and our determina- 
 tions in matters of taste, to which the word 
 sensation is less properly applied. 
 
 I have premised these observations on 
 the meaning of certain words that frequently 
 occur in treating of this subject, for two 
 reasons ; First, That I may be the better 
 understood when I use them ; and, Secondly, 
 That those who would make any progress 
 in this branch of science, may accustom 
 themselves to attend very carefully to the 
 meaning of words that are used in it. They 
 may be assured of this, that the ambiguity 
 of words, and the vague and improper appli- 
 cation of them, have thrown more darkness 
 upon this subject than the subtilty and 
 intricacy of thuigs. 
 
 When we use common words, we ought 
 to use them in the sense in which they are 
 most commonly used by the best and purest 
 writers in the language ; and, vi'hen we have 
 occasion to enlarge or restrict the meaning 
 of a common word, or give it more precision 
 than it has in common language, the reader 
 ought to have warning of this, otherwise we 
 shall impose upon ourselves and upon him. 
 
 A very respectable writer has given a 
 good example of this kind, by explaining, 
 in an Appendix to his •' Elements of Criti- 
 cism," the terms he has occasion to use. 
 In that Appendix, most of the words are 
 explained on which I have been making 
 observations ; and the explication I have 
 given, I think, agrees, for the most part, 
 with his. 
 
 Other words that need explication, shall 
 be explained as they occur. [3G] 
 
 CHAPTER II. 
 
 PRINCIPLES TAKEN FOR GRANTED. 
 
 As there are words common to philosophers 
 and to the vulgar, which need no explica- 
 tion, so there are principles common to both, 
 which need no proof, and which do not 
 admit of direct proof. 
 
 One who applies to any branch of science, 
 must be come to years of understanding, 
 and^ consequently, must have exercised his 
 reason, and the other powers of his mind, 
 in various ways. He must have formed 
 farious opinions and princi]iles, by which he 
 
 conducts himself in the affairs of life. Of 
 those principles, some are common to all 
 men, being evident in themselves, and so 
 necessary in the conduct of life that a man 
 cannot live and act according to the rules 
 of common prudence without them. 
 
 All men that have common understand- 
 ing, agree in such principles ; and consider 
 a man as lunatic or destitute of common 
 sense, who deuies or calls them in question. 
 Thus, if any man were found of so strange 
 a turn as not to believe his own eyes, to 
 put no trust in his senses, nor have the 
 least regard to their testimony, would any 
 man think it worth while to reason gravely 
 with such a person, and, by argument, to 
 convince him of his error ? Surely no wise 
 man would. For, before men can reason 
 together, they must agree in first principles ; 
 and it is impossible to reason with a man 
 who has no principles in common with you. 
 
 There are, therefore, common principles, 
 which are the foundation of all reasoning 
 and of all science. Such common principles 
 seldom admit of direct proof, nor do they 
 need it. Men need not to be taught them ; 
 for they are such as all men of [37] com- 
 mon understanding know ; or such, at least, 
 as they give a ready assent to, as soon as 
 they are proposed and understood. 
 
 Such principles, when we have occasion 
 to use them in science, are called axioms. 
 And, although it be not absolutely neces- 
 sary, yet it may be of great use, to point 
 out the principles or axioms on which a 
 science is grounded. 
 
 Thus, mathematicians, before they prove 
 any of the propositions of mathematics, lay 
 down certain axioms, or common princi- 
 ples, upon which they build their reason- 
 ings. And although those axioms be truths 
 which every man knew before — such as, 
 That the whole is greater than a part. That 
 equal quantities added to equal quantities 
 make equal sums ; yet, when we see no- 
 thing assumed in the proof of mathematical 
 propositions, but such self-evident axioms, 
 the propositions appear more certain, and 
 leave no room for doubt or dispute. 
 
 In all other sciences, as well as in mathe- 
 matics, it will be found that there are a 
 few common principles, upon which all the 
 reasonings in that science are grounded, 
 and into which they may be resolved. If 
 these were pointed out and considered, we 
 should be better able to j udge what stress may 
 be laid upon the conclusions in that science. 
 If the principles be certain, the conclusions 
 justly drawn from them must be certain. 
 If the principles be only probable, the con- 
 clusions can only be probable. If the prin- 
 ciples be false, dubious, or obscure, the 
 superstructure that is built upon them 
 nmst partake of tlie weakness of the found- 
 ation. 
 
 [35-37]
 
 CHAP. II. I 
 
 PRINCIPLES TAKEN FOR GRANTED. 
 
 231 
 
 Sir Isaac Newton, the greatest of na- 
 tural philosophers, has given an example 
 well worthy of imitation, by laying down 
 the common principles or axioms, on which 
 the reasonings in natural philosophy are 
 built. Before this was done, the reason- 
 ings of philosophers in that science were 
 as vague and uncertain as they are in 
 most others. Nothing was fixed ; all was 
 dispute and controversy; [38] but, by 
 this happy expedient, a solid foundation 
 is laid in that science, and a noble super- 
 structure is raised upon it, about which 
 there is now no more dispute or con- 
 troversy among men of knowledge, than 
 there is about the conclusions of mathe- 
 matics. 
 
 It may, however be observed, that the 
 first principles of natural philosophy are of 
 a quite difterent nature from mathematical 
 axioms : they have not the same kind of 
 evidence, nor are they necessary truths, as 
 mathematical axioms are. They are such as 
 these : That similar effects proceed from the 
 same or similar causes ; That we ought to 
 admit of no other causes of natural effects, 
 but such as are true^ and sufficient to ac- 
 count for the effects. These are principles 
 which, though tbey ha ve not the same kind of 
 evidence that mathematical axioms have ; 
 yet have such evidence that every man of 
 common understanding readily assents to 
 them, and finds it absolutely necessary to 
 conduct his actions and opinions by them, 
 in the ordinary affairs of life. 
 
 Though it has not been usual, yet I con- 
 ceive it may be useful, to point out some of 
 those things which I shall take for granted, 
 as first principles, in treating of the mind 
 and its faculties. There is the more oc- 
 casion for this ; because very ingenious 
 men, such as Des Cartes, INIalebranche, 
 Arnauld, Locke, and many others, have 
 lost much labour, by not distinguishing 
 things which require proof, from things 
 which, though they may admit of illustra- 
 tration, yet, being self-evident, do not admit 
 of proof. When men attempt to deduce 
 such self-evident principles from others 
 more evident, they always fall into incon- 
 clusive reasoning : and the consequence of 
 this has been, that others, such as IJerkcley 
 and Hume, finding the arguments brought 
 to prove such first principles to be weak 
 and inconclusive, have been tempted first 
 to doubt of them, and afterwards to deny 
 them. 
 
 It is so irksome to reason with those who 
 deny first principles, that wise men com- 
 monly decline it. Yet it is not impossible, 
 tJiat I'M] what is only a vulgar prejudice 
 may be mistaken for a first princii)lc. Nor 
 is it impossible tliut what is really a first 
 principle may, by the enchantment of words, 
 have HU<-h a mist thiown about it, as t'l 
 
 liide its evidence, and to make a man of 
 candour doubt of it. Such c;ises happen 
 more frequently, perhaps, in this science 
 than in any other ; but they are not alto- 
 gether without remedy. There are ways 
 by which the evidence of first principles 
 may be made more apparent when they are 
 brought into dispute ; but they require to 
 be handled in a way peculiar to themselves. 
 Their evidence is not demonstrative, but 
 intuitive. They require not proof, but to 
 be placed in a proper point of view. This 
 will be shewn more fully in its proper place, 
 and applied to those very principles which 
 we now assume. In the meantime, when 
 they are proposed as first principles, the 
 reader is put on his guard, and warned to 
 consider whether they have a just claim to 
 that character. 
 
 1. First, then, I shall take it for granted, 
 that I think, that I rrmember, that I Tea- 
 son, and, in general, that I really perform 
 all those operations of mind of which I am 
 conscious. 
 
 The operations of our minds are attended 
 with consciousness ; and this consciousness 
 is the evidence, the only evidence, which 
 we have or can have of their existence. If 
 a man should take it into his head to think 
 or to say that his consciousness may de- 
 ceive him, and to require proof that it can- 
 not, I know of no proof that can be given 
 him ; he must be left to himself, as a man 
 that denies first principles, without which 
 there can be no reasoning. Every man 
 finds himself under a necessity of believing 
 what consciousness testifies, and everything 
 that hath this testimony is to be taken as a 
 first principle.* 
 
 2. As by consciousness we know cer- 
 tainly the existence of our ju'cscnt thoughts 
 and passions ; so we know the past by re- 
 membrancer And, when they are re- 
 cent, and the remembrance of them fresh, 
 [40] the knowledge of them, from such 
 distinct remembrance, is, in its certainty 
 and evidence, next to that of conscious- 
 ness. 
 
 3. But it is to be observed that we are 
 conscious of many things to which we give 
 little or no at/ention. We can hardly at- 
 tend to several things at the same time ; 
 and our attention is commonly employed 
 al)out that which is the otiject of our 
 thought, and rarely about the thought it- 
 self. Thus, when a man is angry, bis 
 
 • To doubt that wc arc roniiciniis (pf this or that, 
 is imi)OS>il)Ie. I'or the doubt mu-l at least piiNlulatc 
 it«elf; but the doul)l is oidy a ilaluin of cmiscioug. 
 nest; thereloie, in postulatuiK il» "wii reality, it ad. 
 mits the truth of coiiseiouaiiesii, and consc tjueiitly 
 anndiilatea iHcU. '•ee lielow, i>. .')'il>. <>'" t'"ii- 
 «ciou8iiei.», In (he l)i»tory o»" psycliulOKyi «ee Note H. 
 — H. 
 
 + Remembranre caniinl be taken out of I on. 
 «ciou«ni-ii» See No'i H.— )I
 
 232 
 
 ON THE INTELLPXTUAL POWERS. 
 
 |_ESSAV I. 
 
 attention is turned to the injury done him, 
 or the injurious person; and he gives very 
 little attention to the passion of auger, al- 
 though he is conscious of it. It is in our 
 power, however, wlien we come to the 
 years of understanding, to give attention to 
 our own thoughts and passions, and tlie va- 
 rious operations of our minds. And, wlien 
 we make tliese the objects of our atten- 
 tion, either while they are present or 
 when they are recent and fresh in our me- 
 mory, this act of the mind is called reflec- 
 tion. 
 
 We take it for granted, therefore, that, 
 by attentive reflection, a man may have a 
 clear and certain knowledge of the opera- 
 tions of his own mind ; a knowledge no less 
 clear and certain than that which he has 
 of an external object when it is set before 
 his eyes. 
 
 This reflection is a kind of intuition, it 
 gives a like conviction with regard to in- 
 ternal objects, or things in the mind, as 
 the faculty of seeing gives with regard to 
 objects of sight, A man must, therefore, 
 be convinced beyond possibility of doubt, 
 of everything with regard to the opera- 
 tions of his own mind, which he clearly 
 and distinctly discerns by attentive reflec- 
 tion. • 
 
 4. I take it for granted that all the 
 ' thoughts I am conscious of, or remember, 
 are the thoughts of one and the same 
 ; thinking principle, which I call myself, or 
 my mind. Every man has an immediate 
 and irresistible conviction, not only of his 
 present existence, but of his continued 
 existence and identity, as far back as he 
 can remember. If any man should think 
 fit to demand [41] a proof that the thoughts 
 he is successively conscious of, belong to 
 one and the same thinking principle— if 
 he should demand a proof that he is the 
 same person to-day as he was yesterday, or 
 a year ago — I know no proof that can be 
 given him : he must be left to himself, 
 either as a man that is lunatic, or as one 
 who denies first principles, and is not to be 
 reasoned with. 
 
 Every man of a sound mind, finds liim- 
 
 self under a necessity of believing his own 
 
 identity, and continued existence. The 
 
 conviction of tliis is immediate and irresist- 
 
 able ; and, if he should lose this conviction, 
 
 it would be a certain proof of insanity, 
 
 which is not to be remedied by reasoning. 
 
 '\ 6. I take it for granted, that there are 
 
 i some things which cannot exist by them- 
 
 ; selves, but must be in something else to 
 
 ' which they belong, as qualities, or attributes. 
 
 Thus, motion cannot exist, but in some- 
 
 • See infra, pp. 60, 105, 581, where a similar, and 
 pp. 324, 51lj, where a dijferent extension is given to 
 Reflection. On Attention and Reflection, in the 
 history of psychology, see Note 1— H. 
 
 thing that is moved. And to suppose that 
 there can be motion while everything is at 
 rest, is a gross and palpable absurdity. In 
 like manner, hardness and softness, sweet- 
 ness and bitterness, are things which cannot 
 exist by themselves ; they are qualities of 
 something which is hard or soft, sweet or 
 bitter. That thing, whatever it be, of 
 which they are qualities, is called their sub- 
 ject; and such qualities necessarily suppose 
 a subject. 
 
 Things which may exist by themselves, 
 and do not necessarily suppose the exist- 
 ence of anything else, are called substances ; 
 and, with relation to the qualities or attri- 
 butes that belong to them, they are called 
 the subjects of such qualities or attributes. 
 
 All the things which we immediately per- 
 ceive by our senses, and all the things we 
 are conscious of, are things which must be 
 in something else, as their subject. Thus, 
 by my senses, I perceive figure, colour, 
 hardness, softness, motion, resistance, and 
 such[42] likethings. But these are qualities, 
 and must necessarily be in something that 
 is figured, coloured, hard or soft, that 
 moves, or resists. It is not to these qua- 
 lities, but to that which is the subject of 
 them, that we give the name of body. If 
 any man should think fit to deny that these 
 things are qualities, or that they require any 
 subject, I leave him to enjoy his opinion as 
 a man who denies first principles, and is 
 not fit to be reasoned with. If he has 
 common understanding, he will find that he 
 cannot converse half an hour without say- 
 ing things which imply the contrary of what 
 he professes to believe. 
 
 In like manner, the things I am conscious 
 of, such as thought, reasoning, desire, ne- 
 cessarily suppose something that thinks, 
 that reasons, that desires. We do not give 
 the name of mind to thought, reason, or 
 desire ; but to that being which thinks, 
 which reasons, and which desires. 
 
 That every act or operation, therefore, 
 supposes an agent, tiiat every quality sup- 
 poses a subject, are things which I do not 
 attempt to prove, but take for granted. 
 Every man of common understanding dis- 
 cerns this immediately, and cannot enter- 
 tain the least doubt of it. In all languages, 
 we find certain words which, by gramma- 
 rians, are called adjectives. Such words 
 denote attributes, and every adjective must 
 have a substantive to which it belongs — 
 that is, every attribute must have a subject. 
 In all languages, we find active verbs which 
 denote some action or operation ; and it 
 is a fundamental rule in the grammar of all 
 languages, that such a verb supposes a per- 
 son — that is, in other words, that every 
 action must have an agent. We take it, 
 therefore, as a first principle, that goodness, 
 wisdom, and virtue, can only be in some 
 
 [41, 42]
 
 CHAP. U.] 
 
 PRiNC irLES TAKEN FOR GRANTED. 
 
 233 
 
 being tliat is good, wise, and virtuous ; 
 that thinking supposes a being that thinks ; 
 and that every operation we are conscious 
 of supposes an agent that operates, which 
 we call mind. 
 
 6. I take it for granted, that, in most 
 operations of the mind, there [tS] must be an 
 object distinct from the optr.ition itself. I 
 cannot see, without seeing sometliing. To 
 see without having any object of sight is 
 absurd. I cannot remember, without re- 
 membering something. The thing remem- 
 bered is past, while the remembrance of it 
 is present ; and, therefore, tlie operation 
 and the object of it must be distinct things. 
 The operations of our mind are denoted, in 
 all languages, by active transitive verbs, 
 which, from their construction in grammar, 
 require not only a person or agent, but 
 likewise an object of the operation. Thus, 
 the verb know, denotes an operation of 
 mind. From the general structure of lan- 
 guage, this verb requires a person — I know, 
 you know, or he knows ; but it requires no 
 less a noun in the accusative case, denoting 
 the thing known ; for he that knows must 
 know something ; and, to know, without 
 having any object of knowledge, is an ab- 
 surdity too gross to admit of reasoning * 
 
 7. We ought likewise to take for granted, 
 as first principles, things wherein we find 
 a 1 universal agreement, among the learned 
 and unlearned, in the different nations and 
 ages of the world. -f- A consent of ages and 
 nations, of the learned and A'ulgar, ought, 
 at least, to have great authority, unless we 
 can shew some prejudice as universal as 
 that consent is, which might be the cause 
 of it. Truth is one, but error is infinite. 
 There are many truths so obvious to 
 the human faculties, that it may be ex- 
 pected that men should universally agree in 
 them. And this is actually found to be 
 the case with regard to many truths, against 
 which we find no dissent, unless perhaps 
 that of a few sceptical philosophers, who 
 may justly be suspected, in such cases, to 
 ilifler from the rest of mankind, through 
 pride, obstinacy, or some favourite passion. 
 Wliere there is such universal consent 
 in things not deep nor intricate, but which 
 lie, as it were, on the surface, there is the 
 greatest presumption that can be, that it is 
 the natural result of the human faculties; 
 and it must have great authority with every 
 sober [44] mind that loves truth. Major 
 eniin pais eo fere drferri solet quo a natura 
 (leducitur.—Cir.. de Off. I. 41. 
 
 Perhaps it may be thought that it is 
 impossilile to collect the opinions of all men 
 upon any point whatsoever ; and, there- 
 fore, that this maxim can be of no use. 
 Jiut there are many cases wherein it is 
 
 ♦ Sec NoicB.— H. 
 
 tSrcNote A— H. 
 
 otherwise. Who can doubt, for instance, 
 whether mankind have, in all ages, believed 
 the existence of a material world, and that 
 those things which they see and handle are 
 real, and not mere ilUisions and appari- 
 tions ? Who can doubt whether mankind 
 have universally believed that everything 
 that begins to exist, and every change that 
 happens in nature, must have a cause ? 
 Who can doubt whether mankind have 
 been universally persuaded that there is a 
 right and a wrong in human conduct ? — 
 some things which, in certain circumstan- 
 ces, they ought to do, and other things 
 which they ought not to do ? The univers- 
 ality of these opinions, and of many such 
 that might be named, is sufficiently evi- 
 dent, from the whole tenor of men's con- 
 duct, as far as our acquaintance reaches, 
 and from the records of history, in all 
 ages and nations, that are transmitted to 
 us. 
 
 There are other opinions that appear to 
 be universal, from what is commcm in the 
 structure of all languages, ancient and mo- 
 dern, polished and barbarous. Language is 
 the express image and picture of human 
 thoughts ; and, from the picture,we mayoften 
 draw very certain conclusions with regard 
 to the original. We find in all languages the 
 same parts of speech — nouns substantive 
 and adjective, verbs active and passive, 
 varied according to the tenses of past, pre- 
 sent, and future ; we find adverbs, preposi- 
 tions, and conjunctions. There are general 
 rules of syntax common to all languages. 
 This uniformity in the structure of lan- 
 guage shews a certain degree of uniformity 
 in those notions upon which the structure of 
 language is grounded. 
 
 We find, in the structure of all lan- 
 guages, the distinction of [45] acting and 
 being acted upon, the distinction of action 
 and agent, of quality and subject, and many 
 others of the like kind ; which shews that 
 these distinctions are founded ni the uni- 
 versal sense of mankind. We shall have 
 frequent occasion to argue from tlie sense 
 of mankind expressed in the structure of 
 language ; and therefore it was proper 
 here to take notice of the force of argu- 
 ments drawn from this topic. 
 
 8. I need hardly say that I shall also 
 take for granted such facts as are attested 
 to the conviction of all sober and roasoiuible 
 men, either by our senses, by memory, or 
 by human testimony. Aitliougli sonic; wri- 
 ters on thi.s subject have (lis])uti'd the 
 authority of the senses, of memory, and of 
 every human faculty, vet we find that such 
 persons, in the conduct of life, in i)urKuing 
 their ends, or in avoiding dangers, pay the 
 same regard to tlie autliority of tlieir scukcs 
 and other faculties, as the rest of inaiikind. 
 Hv this they give us just ground lo doulit vi
 
 234 
 
 ON THE INTELLECTUAL POWERS. 
 
 [essay I. 
 
 their candour in their professions of scep- 
 ticism. 
 
 This, indeed, has always been the fate of 
 the few that have professed scepticism, that, 
 when they have done what they can to 
 discredit their senses, they find themselves, 
 after all, under a necessity of trusting to 
 them. Mr Hume has been so candid as to 
 acknowledge this ; aud it is no less true of 
 those who have not shewn the same can- 
 dour ; for I never heard that any sceptic 
 run his head against a post, or stepped into 
 a kennel, because he did not believe his 
 eyes. 
 
 Upon the whole, I acknowledge that we 
 ought to be cautious that we do not adopt 
 opinions as first principles which are not 
 entitled to that character. But there is 
 surely the least danger of men's being im- 
 posed upon in this way, when such prin- 
 ciples openly lay claim to the character, and 
 are thereby fairly exposed to the examina- 
 tion of those who may dispute their au- 
 thority. We do not pretend that those 
 things that are laid down as first principles 
 may not be examined, and that we ought 
 not to [46] have our ears open to what 
 may be pleaded against their being admit- 
 ted as such. Let us deal with them as an 
 upright judge does with a witness who has 
 a fair character. He pays a regard to the 
 testimony of such a witness while his cha- 
 racter is unimpeached ; but, if it can be 
 shewn that he is suborned, or that he is 
 influenced by malice or partial favour, his 
 testimony loses all its credit, and is justly 
 rejected. 
 
 CHAPTER III. 
 
 OF HYPOTHESES. 
 
 Every branch of human knowledge hath 
 its proper principles, its proper foundation 
 and method of reasoning ; and, if we en- 
 deavour to buUd it upon any other found- 
 ation, it will never stand firm and stable. 
 Thus, the historian builds upon testimony, 
 and rarely indulges conjecture ; the anti- 
 quarian mixes conjecture with testimony, 
 and the former often makes the larger 
 ingredient ; the mathematician pays not the 
 least regard either to testimony or conjec- 
 ture, but deduces everything, by demon- 
 strative reasoning, from his definitions and 
 axioms. Indeed, whatever is built upon 
 conjecture, is improperly called science ; 
 for conjecture may beget opinion, but can- 
 not produce knowledge. Natural philoso- 
 phy must be built upon the phsenomena of 
 the material system, discovered by observ- 
 ation and experiment. 
 
 When men first began to philosophize — 
 tliat is, to carry their thoughts beyond the 
 
 objects of sense, and to inquire into the 
 causes of things, and the secret operations 
 of nature — it was very natural for them to 
 indulge conjecture ; nor was it to be ex- 
 pected that, in many ages, they should dis- 
 cover the proper and scientific way of pro- 
 ceeding in philosophical disquisitions. Ac- 
 cordingly, we find that the most ancient 
 systems in every branch of philosophy were 
 nothing but the conjectures of men famous 
 for their wisdom, whose fame gave author- 
 ity to their opinions. Thus, in early ages, 
 [47] wise men conjectured that this earth 
 is a vast plain, surrounded on all hands 
 by a boundless ocean ; that, from this ocean, 
 the sun, moon, and stars emerge at their 
 rising, and plunge into it again at their 
 setting. 
 
 With regard to the mind, men in their 
 rudest state are apt to conjecture that the 
 principle of life in a man is his breath ; be- 
 cause the most obvious distinction between 
 a living and a dead man is, that the one 
 breathes, and the other does not. To this 
 it is owing that, in ancient languages, the 
 word which denotes the soul, is that which 
 properly signifies breath or air. 
 
 As men advance in knowledge, their first 
 conjectures appear silly and childish, and 
 give place to others, which tally better with 
 later observations and discoveries. Thus 
 one system of philosophy succeeds another, 
 without any claim to superior merit, but 
 this — that it is a more ingenious system of 
 conjectures, and accounts better for com- 
 mon appearances. 
 
 To omit many ancient systems of this 
 kind, Des Cartes, about the middle of the 
 last century, dissatisfied with the materia 
 prima, the substantial forms, and the occult 
 qualities of the Peripatetics, conjectured 
 boldly, that the heavenly bodies of our sys- 
 tem are carried round by a vortex or whirl- 
 pool of subtile matter, just as straws and 
 chaff are carried round in a tub of water. 
 He conjectured, that the soul is seated in a 
 small gland in the brain, called the pineal 
 gland ; that there, as in her chamber of 
 presence, she receives intelligence of every- 
 thing that affects the senses, by means of a 
 subtile fluid contained in the nerves, called 
 the animal spirits ; and that she dispatches 
 these animal spirits, as her messengers, to 
 put in motion the several muscles of the 
 laody, as there is occasion.* By such con- 
 
 * It is not, however, to be supposed that Des Cartes 
 allowed the soul to be seated by loral presence in any 
 part of the body ; for the 6malle>t point of body is 
 still extended, and mind is absolutely simple and in- 
 capable of occupying-place. The pineal gland, in the 
 Cartesian doctrine, is only analogically called theseat 
 of the soul, inasmuch as this is viewed as the cen- 
 tral point of the corporeal organism; but while 
 through this point the mind and body are mutually 
 connected, that connection is not one of a mere 
 physical dependence, as they do not operate on each 
 by direct and natural causation.— H. 
 
 [ifi. 17]
 
 CHAP. III.] 
 
 OF HYPOTHESES. 
 
 23i 
 
 jectures as these, Des Cartes could account 
 for everv phanionieuou in nature, in such a 
 plausible manner as gave satisfaction to a 
 great part of the learned world for more 
 than half a century. [48] 
 
 Such conjectures in philosophical matters 
 have commonly got the name of hypotheses, 
 or thturics.' And the invention of a hypo- 
 thesis, founded on some slight probabilities, 
 which accounts for many appearances of 
 nature, hiis been considered as the highest 
 attainment of a philosopher. If the hypo- 
 thesis hangs well together, is embellished 
 by a lively imagination, and serves to ac- 
 count for common appearances, it is con- 
 sidered by many as having all the qualities 
 that should recommend it to our belief, 
 and all that ought to be required in a philo- 
 sophical system. 
 
 There is such proneness in men of genius 
 to invent hypotheses, and in others to 
 acquiesce in them, as the utmost which the 
 human faculties can attain in philosophy, 
 that it is of the last consequence to the pro- 
 gress of real knowledge, that men should 
 have a clear and distinct understanding of 
 the nature of hypotheses in philosophy, and 
 of the regard that is due to them. 
 
 Although some conjectures may have a 
 considerable degree of probabihty, yet it is 
 evidently in the nature of conjecture to be 
 uncertain. In every case the assent ought 
 to be proportioned to the evidence ; for to 
 believe firmly what has but a small degree 
 of probabihty, is a manifest abuse of our 
 understanduig. Now, though we may, in 
 miny cases, form very probable conjectures 
 concerning the worlis of men, every conjec- 
 ture we can form with regard to the works 
 of God has as little probability as the con- 
 jectures of a child with regard to the works 
 of a man. 
 
 The wisdom of God exceeds that of the 
 wisest man, more than his wisdom exceeds 
 that of a child. If a child were to conjec- 
 ture how an army is to be formed in the 
 day of battle — how a city is to be fortified, 
 or a state governed — what chance has he 
 to guess right ? As little chance has the 
 wisest man when he pretends to conjecture 
 how the planets move in their courses, how 
 the sea ebbs and fiows, and how our minds 
 act upon our bodies. [4y] 
 
 If a thousand of the greatest wits that 
 ever the w(jrld jiroiluced were, without any 
 previous knowledge in anatomy, to sit down 
 and contrive how, and by what internal 
 organs, the various functions of the human 
 body are carried on, how the blood is made 
 to circulate and the jiniljs to move, they 
 Would nf)t, in a tliousaud years, iiit upon any- 
 tliing like the trutii. 
 
 Of all the discoveries that have been 
 
 [48-50] 
 
 * Sop above, note *, p. jn, h — H. 
 
 made concerning the inward structure of 
 the human body, never one was made by 
 conjecture. Accurate observations of ana- 
 tomists have brought to light innumerable 
 artifices of Nature in the contrivance of this 
 machine of the human body, which we can- 
 not but admire as excellently adapted to 
 their several purposes. But the most saga- 
 cious physiologist never dreamed of them 
 till they were discovered. On the other 
 hand, innumerable conjectures, formed in 
 different ages, with regard to the structure 
 of the body, have been confuted by obser- 
 vation, and none ever confirmed. 
 
 What we have said of the internal struc- 
 ture of the human body, may be said, with 
 justice, of every other part of the works of 
 God, wherein any real discovery has been 
 made. Such discoveries have always been 
 made by patient observation, by accurate 
 experiments, or by conclusions drawn by 
 strict reasoning from observations and ex- 
 periments ; and such discoveries have always 
 tended to refute, but not to confirm, the 
 theories and hypotheses which ingenious 
 men have mvented. 
 
 As this is a fact confirmed by the history 
 of philosophy in all past ages, it ought to 
 have taught men, long ago, to treat with 
 just contempt hypotheses in every branch 
 of philosophy, and to despair of ever ad- 
 vancing real knowledge in that way. The 
 Indian philosopher, being at a loss to know 
 how the earth was supported, invented the 
 hypothesis of a huge elephant ; and this 
 elephant he supposed to stand upon the 
 back of a huge tortoise. This hypothesis, 
 however ridiculous it appears to us, might 
 seem very reasonable [50] toother Indians, 
 who knew no more than the inventor of it ; 
 and the same will be the fate of all hypo- 
 theses invented by men to account for the 
 works of God. They may have a decent 
 and plausible appearance to those who are 
 not more knowing than the inventor ; but, 
 when men come to be more enlightened, 
 they will always appear ridiculous and 
 childish. 
 
 This has been the case with regard to 
 hypotheses that have been revered by the 
 most enlightened part of mankind for hun- 
 dreds of years ; and it will always be tlie 
 case to the end of the world. For, until 
 the wisdom of men bear some proportion to 
 the wisdom of (iod, their atti'm])ts to find 
 out the structure of his works, by the force 
 of their wit and genius, will Ije vain. 
 
 The finest productions of human art are 
 immensely sliort of the meanest works of 
 Nature. The nicest .-irtlst cannot make a 
 feather or the leaf of a tree. llinnan 
 workmanship will never bear a comiiaiison 
 with divine. Conjectures and liypollieseH 
 arc the invention and the worknianship of 
 men, and must bear projiortion to the capu-
 
 236 
 
 OX THE INTELLECTUAL POWERS. 
 
 [essay 
 
 city and skill of the inventor ; .and, there- 
 fore, will always be veiy unlike to the 
 works of God, which it is the business of 
 philosophy to discover. 
 
 The world has been so long befooled by 
 hypotheses in all parts of philosophy, that 
 it is of the utmost consequence to every 
 man who would make any progress in real 
 knowledge, to treat them with just con- 
 tempt, as the reveries of vain and fanciful 
 men,whose pride makes them conceive them- 
 selves able to unfold the mysteries of nature 
 by the force of their genius. A learned man, 
 in an epistle to Des Cartes, has the follow- 
 ing observation, which very much deserved 
 the attention of that philosopher, and of all 
 that come after him : — " When men, sit- 
 ting in their closet, and consulting only 
 their books, attempt disquisitions into nature, 
 they may, indeed, tell how they would have 
 made the world, if God had given them that 
 in commission ; tliat is, they may describe 
 [51] chimeras, which correspond with the 
 imbecility of their own minds, no less than 
 the admirable beauty of the universe cor- 
 responds with the infinite perfection of its 
 Creator ; but without an understanding 
 truly divine, they can never form such an 
 idea to themselves as the Deity had in 
 creating things." 
 
 Let us, therefore, lay down this as a 
 fundamental principle in our inquiries into 
 the structure of the mind and its opera- 
 tions — that no regard is due to the conjec- 
 tures or hypotheses of philosophers, how- 
 ever ancient, however generally received. 
 Let us accustom ourselves to try every 
 opinion by the touchstone of fact and ex- 
 perience. What can fairly be deduced 
 from facts duly observed or sufficiently at- 
 tested, is genuine and pure ; it is the voice 
 of God, and no fiction of human imagina- 
 tion. 
 
 The first rule of philosophising laid down 
 by the great Newton, is this : — Causas re- 
 rum naturalmm, non plurcs admitli debere, 
 quam quce et verce sint, et earum phceno 
 menis expUctindis svfficiant. " No more 
 causes, nor any other causes of natural 
 effects, ought to be admitted, but such as 
 are both true, and are sufficient for ex- 
 plaining their appearances.'' This is a golden 
 rule ; it is the true and proper test, by 
 which what is sound and solid in philoso- 
 phy may be distinguished from what is hol- 
 low and vain.* 
 
 If a philosopher, therefore, pretends to 
 shew us the cause of any natural effect, 
 whether relating to matter or to mind, let 
 us first consider whether there is sufficient 
 
 • For this rule we are not indebted to Newton. 
 It is only the old law of parcimony, and that ainbigu. 
 (lusiy expressed. For, in their plain incaiiing, the 
 « I irds"("/'i'c;<s«(n<" are redundant ; or wliat follows is 
 rcdund.mf, and the whole rule a barren truism.— H. 
 
 evidence that the cause he assigns does 
 really exist. If there is not, reject it with 
 disdain, as a fiction which ought to have no 
 place in genuine philosophy. If the cause 
 assigned really exists, consider, in the next 
 place, whether the effect it is brought to 
 explain necessarily follows from it. Un- 
 less it has these two conditions, it is good 
 for nothing. 
 
 When Newton had shewn the admirable 
 effects of gravitation in our planetary sys- 
 tem, he must have felt a strong desire to 
 know [52] its cause. He could have in- 
 vented a hypothesis for this purpose, as 
 many had done before him. But his phi- 
 losophy was of another complexion. Let 
 us hear what he says : Rafionem harum 
 gravitalis proprietatum ex phcenomems non 
 pr/tui deitucere, et hypotheses non Jingo. 
 Qulcqidd enim ex-pha:nomenis non deduct- 
 tur hypothesis vocanda est. Et hypotheses^ 
 sen metaphysi((B, seu physicce, seu qualila- 
 tum occultarum, seu mechanics, in philoso- 
 phia experimentali locum non hubent. 
 
 CHAPTER IV. 
 
 OF ANALOGY. 
 
 It is natural to men to judge of things 
 less known, by some similitude they ob- 
 serve, or think they observe, between them 
 and things more familiar or better known. 
 In many cases, we have no better way of 
 judging. And, where the things compared 
 have really a great similitude in their na- 
 ture, when there is reason to think that they 
 are subject to the same laws, there may be 
 a considerable degree of probabihty in con- 
 clusions drawn from analogy. 
 
 Thus, we may observe a very great si- 
 militude between this earth which we in- 
 habit, and the other planets, Saturn, Ju- 
 piter, Mars, Venus, and Mercury. They 
 all revolve round the sun, as the earth 
 does, although at different distances and 
 in different periods. They borrow all their 
 light from the sun, as the earth does. 
 Several of them are known to revolve round 
 their axis like the earth, and, by that 
 means, must have a like succession of day 
 and night. Some of them have moons, 
 that serve to give them light in the absence 
 of the sun, as our moon does to us. They 
 are all, in their motions, subject to the 
 same law of gravitation, as the earth is. 
 From all this similitude, it is not unrea- 
 sonable to think, that those planets may, 
 like our earth, be the habitation of va- 
 rious [ 53] orders of living creatures. There 
 is some probability in this conclusion from 
 analogy. 
 
 In medicine, physicians must, for the 
 most part, be directed in their prescriptions 
 
 r.M-531
 
 CHAP. IV.] 
 
 OF ANALOGY. 
 
 237 
 
 by analogy. The constitution of one human 
 body is so like to that of another that it is 
 reasonable to think that what is the cause 
 of health or sickness to one, may have the 
 same effect upon another. And this ge- 
 nerally is found true, though not without 
 some exceptions. 
 
 In politics we reason, for the most part, 
 from analogy. The constitution of Iiuman 
 nature is so similar in different societies or 
 commonwealths, that the causes of peace 
 and war, of tranquillity and sedition, of 
 riches and poverty, of uupi-ovement and 
 degeneracy, are much the same in all. 
 
 Analogical reasoning, therefore, is not, 
 in all cases, to be rejected. It may afford 
 a greater or a less degree of probability, 
 according as the tliuigs compared are more 
 or less similar in their nature. But it 
 ought to be observed, that, as this kind of 
 reasoning can afford only probable evidence 
 at best ; so, unless great caution be used, 
 w-e are apt to be led into error by it. For 
 men are naturally disposed to conceive a 
 greater similitude in things than there 
 really is. 
 
 To give an instance of this : Anatomists, 
 in ancient ages, seldom dissected human 
 bodies ; but very often the bodies of those 
 quadrupeds whose internal structure was 
 thought to approach nearest to that of the 
 human body. Modern anatomists have 
 discovered many mistakes the ancients 
 were led into, by their conceiving a greater 
 similitude between the structure of men 
 and of some beasts than there is in reality. 
 By this, and many other instances that 
 might be given, it appears that conclusions 
 built on analogy stand on a slippery founda- 
 tion ; and that we ought never to rest upon 
 evidence of this kind, when we can have 
 more direct evidence. [54] 
 
 I know no autlior who has made a more 
 just and a more happy use of this mode of 
 reasoning than Bisho[) Butler, in his " Ana- 
 logy of Religion, Natural and Revealed, to 
 the Constitution and Course of Nature." 
 In that excellent work the author does not 
 ground any of the truths of religion upon 
 analogy, as their proper evidence. He 
 only makes use of analogy to answer objec- 
 tions against them. When olijections are 
 made against the truths of religion, whicli 
 may be made with equal .strength against 
 what we know to be true in the course 
 of nature, such objections can have no 
 weight. 
 
 Analogical reasoning, therefore, may be 
 of excellent use in answering objections 
 against trutlis which have otlier evidence. 
 It may lik(;wise give a, greater or a. less 
 degree of probability in cases where we can 
 find no other evidence. But all arguments, 
 drawn from arudogy, arc; still tlie weaker, 
 the greater diHjjarity tiiere is )jetw('en the 
 r51-. 55] 
 
 things compared ; and, therefore, must be 
 weakest of all when we compare body with 
 mind, because there are no two things in 
 nature more unlike. 
 
 There is no subject in which men have 
 always been so prone to form their notions 
 by analogies of this kind, as in what re- 
 lates to the mind. "We form an early ac- 
 quaintance with material things by means 
 of our senses, and are bred up in a con- 
 stant familiarity with tliem. Hence we 
 are apt to measure all things by them ; and 
 to ascribe to things most remote from mat. 
 ter, the qualities that belong to material 
 things. It is for this reason, that man- 
 kind have, in all ages, been so prone to 
 conceive the mind itself to be some sub- 
 tile kind of matter : that they have been 
 disposed to ascribe human figure and hu- 
 man organs, not only to angels, but even 
 to the Deity. Though we are conscious of 
 the operations of our own minds when they 
 are exerted, and are capable of attending 
 to them, so as to form a distinct notion of 
 them, this is so difficult a work to men 
 w'hose attention is constantly solicited by 
 external objects, that we give tliem names 
 from things that are familiar, and whiclx 
 [55] are conceived to have some similitude 
 to them ; and the notions we form of them 
 ai"e no less analogical than tlie names we 
 give them. Almost all the words by which 
 we express the operations of the mind, are 
 bori'owed from material objects. To un- 
 derstand, to conceive, to imagine, to com- 
 prehend, to deliberate, to infer, and many 
 others, are words of this kind ; so that the 
 very language of mankind, with regard to 
 the operations of our minds, is analogical. 
 Because bodies are affected only by con- 
 tact and pressure, we are apt to conceive 
 that what is an immediate object of thouglit, 
 and affects the mind, must be in contact 
 with it, and make some impression U])on 
 it. When we imagine anything, the very 
 word leads ns to think that tliero nuist be 
 some image in the mind of the tiling con- 
 ceived. It is evident that these notions 
 are drawn from some similitude conceived 
 between body and mind, and between the 
 properties of body and the operations of 
 mind- 
 To illustrate more fully tliat analogical 
 reasoning from a supposed similitude of 
 mind to body, which I conceive to be the 
 most fruitful source of error with regard to 
 the operations of our minds, I shall give an 
 instance of it. 
 
 When a man is urged by contrary motivra 
 — those on one hand inciting him to do some 
 action, those on the other to forbear it — lie 
 deliberates about it, and at last resolves to 
 do it, or not to doit. The contrary motive* 
 are here compared to the weights in tlie 
 opposite scales of a balance ; and there ia
 
 23a 
 
 ON THE INTKLLECTUAL POWERS. 
 
 [essay 
 
 not, perhaps, any instance that can be 
 named of a more striking analogy between 
 body and mind. Hence the phrases of 
 weighing motives, of deliberating upon 
 actions, are commoff to all languages. 
 
 From this analogy, some pliHosophers 
 draw very important conclusions. They 
 say, that, as the balance cannot incline to 
 one side more than the other when the 
 opposite weights are equal, so a man can- 
 not possibly determine himself if the motives 
 on both hands are equal ; and, as the bal- 
 ance must necessarily turn to that side [56] 
 which has most weight, so the man must 
 necessarily be determined to that hand 
 where the motive is strongest. And on 
 this foundation some of the schoolmen" 
 maintained that, if a hungry ass were 
 placed between two bundles of hay equally 
 inviting, the beast must stand still and starve 
 to death, being unable to turn to either, 
 because there are equal motives to both. 
 This is an instance of that analogical rea- 
 soning which I conceive ought never to be 
 trusted ; for the analogy between a balance 
 and a man deliberating, though one of the 
 strongest that can be found between matter 
 and mind, is too weak to support any argu- 
 ment. A piece of dead inactive matter, 
 and an active intelligent being, are things 
 very unlike; and, because the one would 
 remain at rest in a certain case, it does not 
 follow that the other would be inactive in a 
 ease somewhat similar. The argument is 
 no better than this — That, because a dead 
 animal moves only as it is pushed, and, if 
 pushed with equal force in contrary direc- 
 tions, must remain at rest ; therefore, the 
 same thing must happen to a living animal ; 
 for, surely, tlirc similitude between a dead 
 animal and a living, is as great as that 
 between a balance and a man. 
 
 The conclusion I would draw from all 
 that has been said on analogy, is, that, in 
 our inquiries concerning the mind and its 
 operations, we ought never to trust to rea- 
 sonings drawn from some supposed simili- 
 tude of body to mind ; and that we oug^it 
 to be very much upon our guard that we 
 be not imposed upon by those analogical 
 terms and phrases, by which the operations 
 of the mind are expressed in all languages. 
 [57] 
 
 • This illustration Is specially associated with 
 Joannes Buridanus, a celebrated Nominalist of the 
 14th century, and oiieK)t'the acutest reasoners on the 
 great question of moral liberty. The supposition 
 of the ass, \c., is not, however, as I have ascertained, 
 to be found in his writings. Perhaps it was orally 
 advanced ui disputation, or in lecturing, as an ex- 
 ample in illustration of his De'erminism ; perhaps it 
 was employed by his opponents as an instance to 
 reduce that doctrine to absurdity. With this latter 
 view, a similar refutation of the principles of our 
 mo li'rn Fatalists was, as we have seen, ingeniously 
 essayed by Reid's friend and kinsman, Ur James 
 Gregory. — H. 
 
 CHAPTER V. 
 
 OF THE PROPER MEANS OP KNOWING THE 
 OPERATIONS OF THE MIND. 
 
 Since we ought to pay no regard to hypo- 
 theses, and to be very suspicious of analo- 
 gical reasoning, it may be asked, From what 
 source must the knowledge of the mind 
 and its faculties be drawn ? 
 
 I answer, the chief and proper source of 
 this branch of knowledge is accurate reflec- 
 tion upon the operations of our own minds. 
 Of this source we shall speak more fully, 
 after maldng some remarks upon two others 
 that may be subservient to it. The first of 
 them is attention to the structure of lan- 
 guage. 
 
 The language of mankind is expressive of 
 their thoughts, and of the various opera- 
 tions of their minds. The various opera- 
 tions of the understanding, will, and pas- 
 sions, which are common to mankind, have 
 various forms of speech corresponding to 
 them in all languages, which are the signs 
 of them, and by which they are expressed : 
 And a due attention to the signs may, in 
 many cases, give considerable light to the 
 things signified by them. 
 
 There are in all languages modes of 
 speech, by which men signify their judg- 
 ment, or give their testimony ; by which 
 they accept or refuse ; by which they ask 
 information or advice ; by which they com- 
 mand, or threaten, or supplicate ; by which 
 they plight their faith in promises or con- 
 tracts. If such operations were not com- 
 mon to mankind, we should not find in all 
 languages forms of speech, by which they 
 are expressed. 
 
 All languages, indeed, have their imper- 
 fections — they can never be adequate to all 
 the varieties of human thought ; and there- 
 fore things may be really distinct in their 
 nature, and capable of being distinguished 
 by the human mind, which are not distin- 
 guished [58] in common language. We can 
 only expect, in the structure of languages, 
 those distinctions Avhich all mankind in the 
 common business of life have occasion to 
 make. 
 
 There may be peculiarities in a particular 
 language, of the causes of which we are 
 ignorant, and from which, therefore, we can 
 draw no conclusion. But whatever we find 
 common to all languages, must have a com- 
 mon cause ; must be owing to some com- 
 mon notion or sentiment of the human 
 mind. 
 
 We gave some examples of this before, 
 and shall here add another. All languages 
 have a plural number in many of their 
 nouns ; from which w» may infer that all 
 men have notions, not of individual things 
 
 [56-58J
 
 .AP. V.J 
 
 ot'ERATlONS OF THE MIND. 
 
 239 
 
 only, but of attributes, or things which are 
 common to many individuals ; tor no indi- 
 vidual can have a plural number. 
 
 Another source of information in this 
 subject, is a due attention to the course of 
 human actions and conduct. The actions 
 of men are effects ; their sentiments, their 
 passions, and their affections, are the causes 
 of those effects ; and we may, in many cases, 
 form a judgment of the cause from the 
 effect. 
 
 The beha%'iour of parents towards their 
 children gives sufficient evidence even to 
 those who never had children, that the 
 parental affection is common to mankind. 
 It is easy to see, from the general conduct 
 of men, what are the natural objects of their 
 esteem, their admiration, their love, their 
 approbation, their resentment, and of all 
 their other original dispositions. It is 
 obvious, from the conduct of men in all 
 ages, that man is by his nature a social 
 animal ; that he delights to associate with 
 his species ; to converse, and to exchange 
 good offices with them. 
 
 Not only the actions, but even the opi- 
 nions of men may sometimes give light 
 into the frame of the human mind. The 
 opinions of men may be considered as the 
 effects of their intellectual powers, [59] as 
 their actions are the effects of their active 
 principles. Even the prejudices and errors 
 of mankind, when they are general, must 
 have some cause no less general ; the dis- 
 covery of which will throw some light upon 
 the frame of the human understanding. 
 
 I conceive this to be the principal use of 
 the history of philosophy. When we trace 
 the history of the various philosophical opin- 
 ions that have sprung up among thinking 
 men, we are led into a labyrinth of fanciful 
 opinions, contradictions, and absurdities, 
 intermixed with some truths ; yet we may 
 sometimes find a clue to lead us through the 
 several windings of this labyrinth. We may 
 find that point of view which presented 
 things to the author of the system, in the 
 li^ht in which they appeared to him. This 
 will often give a consistency to things seem- 
 ingly contradictory, and some degree of 
 probability to those that appeared most 
 fanciful. • 
 
 The history of philosophy, considered as 
 a map of the intellectual operations of men 
 of genius, must always be entertaining, and 
 may sometimes give us views of the human 
 understanding, which could not easily be had 
 any other way. 
 
 I return to what I mentioned as the main 
 source of information on this subject — at- 
 tentive reflection upon the operations of our 
 own minds. 
 
 • '•' I- very error," »ay» Uos«uet, 
 uliiueH."— H. 
 
 '• is a trutli 
 
 All the notions we have of mind and of 
 its operations, are, by Mr Locke, called 
 ideas of reflectioii.* A man may have as 
 distinct notions of remembrance, of judg- 
 ment, of will, of desire, as he has of any 
 object whatever. Such notions, as Mr 
 Locke justly observes, are got by the power 
 of reflection. But what is this power of 
 reflection ? " It is," says the same author, 
 " that power by which the mind turns its 
 view inward, and observes its own actions 
 and operations." He observes elsewhere, 
 " That the understanding, like the eye, 
 whilst it makes us see and perceive all [60] 
 other things, takes no notice of itself; and 
 that it requires art and pains to set it at a 
 distance, and make it its own object." 
 Cicero hath expressed this sentiment most 
 beautifully. Tusc. I. 28. 
 
 This power of the understanding to make 
 its own operations its object, to attend to 
 them, and examine them on all sides, is the 
 power of reflection, by which alone we can 
 have any distinct notion of the powers of our 
 own or of other minds. 
 
 This reflection ought to be distinguished ^ 
 from consciousness, with which it is too 
 often confounded, even by Mr Locke. All 
 men are conscious of the operai ions of their 
 own minds, at all times, while they are 
 awake ; but there are few who reflect upon 
 them, or make them objects of thought. 
 
 From infancy, till we come to the years 
 of understanding, we are employed solely 
 about external objects. And, although the 
 mind is conscious of its operations, it does 
 not attend to them ; its attention is turned 
 solely to the external objects, about which 
 those operations are employed. Thus, when 
 a man is angry, he is conscious of his pas- 
 sion ; but his attention is turned to the 
 person who offended him, and the circum- 
 stances of the ofi'ence, while the passion of 
 anger is not in the least the object of his 
 attention. 
 
 I conceive this is sufficient to shew the 
 difference between consciousness of the 
 operations of our minds, and reflection upon 
 them ; and to shew that wc may have the 
 former without any degree of the latter. 
 The difference between consciousness and 
 reflection, is like to tlie difference between 
 a superficial view of an object which pre- 
 sents itself to the eye while we are engaged 
 about something else, and that attentive 
 examination which we give to an object 
 when we are wholly employed in surveying 
 it. Attention is a voluntary act ; it re- 
 quires an active cxerfion to Ijeijin ami to 
 continue it, and it may be continued as 
 long as we will; but consciousness [Gl] is 
 
 • Locke 18 not (as Ueiil nueiiis I" tliiiik, ami an M, 
 Stewart expressly says) the llrst who iiitroilmrd He. 
 flection eiliier as a imcholoKiral term, or aptycbota 
 gical |iriiici|)le. .See Note I.— II. 
 
 169-611
 
 240 
 
 ON THE INTELLECTUAL POWERS. 
 
 [essay 
 
 involuntary and of no continuance, changing 
 with every thought. 
 
 The power of reflection upon the oper- 
 ations of their own minds, does not appear 
 at all in children. Men must be come to 
 some ripeness of understanding before they 
 are capable of it. Of all the powers of the 
 human mind, it seems to be the last that 
 unfolds itself. Most men seem incapable of 
 acquiring it in any considerable degree. 
 . Like all our other powers, it is greatly im- 
 \ proved by exercise ; and until a man has 
 got the habit of attending to the operations 
 of his own mind, he can never have clear 
 and distinct notions of them, nor form any 
 steady judgment concerning them. His 
 opinions must be borrowed from others, his 
 notions confused and indistinct, and he may 
 easily be led to swallow very gross absurd- 
 ities. To acquire this habit, is a work of 
 time and labour, even in those who begin it 
 early, and whose natural talents are toler- 
 ably fitted for it ; but the difficulty will be 
 daily diminishing, and the advantage of it 
 is great. They will, thereby, be enabled to 
 think with precision and accuracy on every 
 subject, especially on those subjects that 
 are more abstract. They will be able to 
 judge for themselves in many important 
 points, wherein others must blindly follow a 
 > leader. 
 
 CHAPTER VI. 
 
 OF THE DIFFICULTY OF ATTENDING TO THE 
 OPERATIONS OF OUR OWN MINDS. 
 
 The difficulty of attending to our mental 
 operations, ought to be well understood, and 
 justly estimated, by those who would make 
 any progress in this science ; that they may 
 neither, on the one hand, expect success 
 without pains and application of thought ; 
 nor, on the other, be discouraged, by con- 
 ceiving that the obstacles that lie in the way 
 are insuperable, and that there is no cer- 
 tainty to be attained in it. I shall, there- 
 fore, endeavour to point [G2] out the causes 
 of this difficulty, and the effects that have 
 arisen from it, that we may be able to form 
 a true judgment of both. 
 
 1 . The number and quick succession of 
 the operations of the mind, make it difficult 
 to give due attention to them. It is well 
 known that, if a great number of objects be 
 presented in quick succession, even to the 
 eye, they are confounded in the memory 
 and imagination. We retain a confued 
 notion of the whole, and a more confused 
 one of the several parts, especially if they 
 are objects to which we have never before 
 given particular attention. No succession 
 can be more quick tlian that of thought. 
 The mind is busy while we are awake, con- 
 
 tinually passing from one thought and one 
 operation to another. The scene is con- 
 stantly shifting. Every man will be sen- 
 sible of this, who tries but for one minute 
 to keep the same thought in his imagination, 
 without addition or variation. He will find 
 it impossible to keep the scene of his imagin- 
 ation fixed. Other objects will intrude, 
 without being called, and all he can do is to 
 reject these intruders as quickly as possible, 
 and return to his principal object. 
 
 2. In this exercise, we go contrary to 
 liabits which have been early acquired, and 
 confirmed by long unvaried practice. From 
 infancy, we are accustomed to attend to 
 objects of sense, and to them only ; and, 
 when sensible objects have got such strong 
 hold of the attention by confirmed habit, it 
 is not easy to dispossess thern. When we 
 grow up, a variety of external objects 
 solicits our attention, excites our curiosity, 
 engages our affections, or touches our pas- 
 sions ; and the constant round of employ- 
 ment, about external objects, draws off the 
 mind from attending to itself; so that 
 nothing is more just than the observation 
 of Mr Locke, before mentioned, " That the 
 understanding, like the eye, wliile it sur- 
 veys all the objects around it, commonly 
 takes no notice of itself." 
 
 3. The operations of the mind, from their 
 very nature, lead the mind to give its atten- 
 tion to some other object. Our sensations, 
 [6.3] as will be shewn afterwards, are natu- 
 ral signs, and turn our attention to the things 
 signified by them ; so much thrit most of 
 them, and those the most frequent and 
 familiar, have no name in any language. In 
 perception, memory, judgment, imagination, 
 and reasoning, there is an object distinct 
 from the operation itself ; and, whi'eweare 
 led by a strong impulse to attend to the 
 object, the operation escapes our notice. 
 Our passions, affections, and all our active 
 powers, have, in like manner, their objects 
 which engross our attention, and divert it 
 from the passion itself. 
 
 4. To this we may add a just observation 
 made by Mr Hume, That, when the mind 
 is agitated by any passion, as soon as we 
 turn our attention from the object to the 
 paRsion itself, the passion subsides or van- 
 ishes, and, by that means, escapes our 
 inquiry. This, indeed, is common to almost 
 every operation of the mind. When it is 
 exerted, we are conscious of it ; but then 
 we do not attend to the operation, but to 
 its object. When the mind is drawn off 
 from the object to attend to its own opera- 
 tion, that operation ceases, and escapes our 
 notice. 
 
 5. As it is not sufficient to the discovery 
 of mathematical truths, that a man be able 
 to attend to mathematical figures, as it is 
 necessary that he should have the ability to 
 
 [69, 63]
 
 (HAP. VI.3 
 
 OPERATIONS OF THE MIND. 
 
 241 
 
 listinguish accurately things that differ, 
 and to discern clearly the various relations 
 of the quantities he compares — an ability 
 which, though much greater in those who 
 have the force of genius than in others, 
 yet, even in them, requires exercise and 
 habit to bring it to maturity — so, in order 
 to discover the truth in what relates to the 
 operations of the mind, it is not enough that 
 ( a man be able to give attention to them : 
 he must have the ability to distinguish ac- 
 curately their minute differences ; to resolve 
 and analyse complex operations into their 
 simple ingredients ; to unfold the ambiguity 
 of words, which in this science is greater 
 than in any other, and to give them the same 
 accuracy and precision that mathematical 
 terms have ; for, indeed, the same precision 
 in the use of words, the same cool attention 
 to [64] the minute differences of things, 
 the same talent for abstraction and analys- 
 ing, which fit a man for the study of math- 
 ematics, are no less necessary in this. But 
 there is thisgreat difference between the two 
 sciences — that the objects of mathematics 
 being things external to the mind, it is 
 much more easy to attend to them, and fix 
 them steadily in the imagination. 
 
 The difficulty attending our inquiries 
 into the powers of the mind, serves to 
 account for some events respecting this 
 branch of philosophy, which deserve to be 
 mentioned. 
 
 While most branches of science have, 
 either in ancient or in modern times, been 
 highly cultivated, and brought to a con- 
 siderable degree of perfection, this remains, 
 to this day, in a very low state, and, as it 
 were, in its infancy- 
 
 Every science invented by men must 
 have its beginning and its progress ; and, 
 from various causes, it may happen that 
 one science shall be brought to a great 
 degree of maturity, while another is yet in 
 ^ its infancy. The maturity of a science may 
 be judged of by this — When it contains a 
 system of principles, and conclusions drawn 
 from them, which are so firmly established 
 that, among thinking and intelligent men, 
 there remains no doubt or dispute about 
 them ; so that those who come after may 
 raise the superstructure higher, but shall 
 never be able to overturn what is already 
 built, in order to begin on a new founda- 
 tion. 
 
 Geometry seems to have been in its in- 
 fancy about the time of Thales and Pytha- 
 goras ; liecausc many of tlie elementary 
 propositions, on which the whole science is 
 built, are ascribed to them as the inventors. 
 Euclid's '' Elements," which were written 
 some ages after Pythagoras, exiiibit a sys- 
 tem of geometry which deserves the name 
 of a science; and, tliough great additions 
 have been made by ApoUoiiius, Archi- 
 
 rci-tiG] 
 
 modes. Pappus, and others among the an- 
 cients, and still greater by the moderns ; 
 yet what [65] was laid down in Euclid's 
 " Elements" was never set aside. It re- 
 mains as the firm foundation of all future 
 superstructures in that science. 
 
 Natural philosophy remained in its in- 
 fant state near two thousand years after 
 geometry had attained to its manly form : 
 for natural philosophy seems not to have 
 been built on a stable foundation, nor carried 
 to any degree of maturity, till the last cen- 
 turj'. The system of Des Cartes, which was 
 all hypothesis, prevailed in the most enlight- 
 eiied part of Europe till towards the end of 
 last century. Sir Isaac Newton has the 
 merit of giving the form of a science to this 
 branch of ]ihilosophy ; and it need not ap- 
 pear surprising, if the philosophy of the 
 human mind should be a century or two 
 later in being brought to maturity. 
 
 It has received great accessions from the 
 labours of several modern authors ; and 
 perhaps wants little more to entitle it to the 
 name of a science, but to be purged of cer- 
 tain hypotheses, which have imposed on 
 some of the most acute writers on this sub- 
 ject, and led them into downright scepticism. 
 What the ancients have delivered to us 
 concerning the mind and its operations, is { 
 almost entirely drawn, not from accurate 
 reflection, but from some conceived analogy 
 between body and mind. And, although 
 the modern authors I formerly named have 
 given more attention to the operations of 
 their own minds, and by that means have 
 made important discoveries, yet, by re- 
 taining some of the ancient analogical no- 
 tions, their discoveries have been less use- 
 ful than they might have been, and have 
 led to scepticism. 
 
 It may happen in science, as in building, 
 that an error in the foundation slwll weaken 
 the whole ; and the farther the building is 
 carried on, this weakness shall become the 
 more apparent and the more threatening. 
 Something of this kind seems to have hap- 
 pened in our systems concerning the mind. 
 The accession they [GG] have received by 
 modern discoveries, though very important in 
 itself, has thrown darkness and obscurity 
 upon the whole, and has led men rather to 
 scepticism than to knowledge. This must 
 be owing to some fundamental errors that 
 have not l)ccii observed ; and when these 
 are corrected, it is to be hoped that the im- 
 provements that have been made will have 
 their due effect. 
 
 The last effect I observe of the difficulty 
 of inquiries into tiie jjowers of the mind, is, 
 that there is no otlu.T jjart of liuman know- 
 ledge in which ingenious authors liave been 
 so apt to run into strange paradoxes, and 
 even into gross absurdities. 
 
 When we ('mil philosophers maintaining 
 
 It
 
 242 
 
 ON THE INTELLECTUAL POWERS. 
 
 ^ESSAV 
 
 that there is no heat in the fire, nor colour 
 in tlie rainbow ;* when we find the gravest 
 philosophers, from Des Cartes down to 
 Bishop Berkeley, mustering up arguments 
 to prove the existence of a material world, 
 and unable to find any that will bear ex- 
 amination ; when we find Bishop Berkeley 
 and Mr Hume, the acutest metaphysicians 
 of the age, maintaining that there is no such 
 thing as matter in the universe — that sun, 
 moon, and stars, the earth which we inhabit, 
 our own bodies, and those of our friends, are 
 only ideas in our minds, and have no exist- 
 ence but in thought ; when we find the 
 last maintaining that there is neither body 
 nor mind — nothing in nature but ideas and 
 impressions, without any substance on which 
 they are impressed — that there is no cer- 
 tainty, nor indeed probability, even in ma- 
 thematical axioms : I say, when we consider 
 such extravagancies of many of the most 
 acute writers on this subject, we may be apt 
 to think the whole to be only a dream of 
 fanciful men, who have entangled them- 
 selves in cobwebs spun out of their own 
 brain. But we ought to consider that the 
 more closely and ingeniously men reason 
 from false principles, the more absurdities 
 they will be led into ; aiid when such absur- 
 dities help to bring to light the false prin- 
 ciples from which ihey are drawn, they may 
 he the more easily forgiven. [67] 
 
 CHAPTER VIL 
 
 DIVISION OF THE POWERS OF THE MIND. 
 
 The powers of the mind are so many, so 
 various, and so connected and complicated 
 in most of its operations, that there never 
 has been any division of them proposed 
 which is not liable to considerable objec- 
 tions. We shall, therefore, take that gene- 
 ral division which is the most common, into 
 the powers of understanding and those of 
 wiU.-\ Under the will we comprehend our 
 active powers, and all that lead to action, 
 or influence the mind to act — such as appe- 
 tites, passions, affections. The understand- 
 ing comprehends our contemplative powers ; 
 by which we perceive objects ; by which 
 we conceive or remember them ; by which 
 we analyse or compound them ; and by which 
 we judge and reason concerning them. 
 
 • A merely verbal dispute. See before, p. 2i 5, b, 
 note.— H. 
 
 t It would be out of place to enter on the exten. 
 »i»e field of history and discussion relativp to the 
 distribution of our menial |iowers. It is sufficient 
 to say, that the vulgar division of the faculties, 
 adopted by Reid, into those of the Understanding 
 and those of the fVilL is to be traced to the classifi. 
 cation, taken in the Aristotelic school, of the powers 
 into e^wstic, or cognitive, and orectic, or appetent 
 On this the reader may consult the admirable<intro- 
 duction of Philoponus— or rather of Ammonius Her- 
 miie— to the books of Aristotle upon the Soul. — H. 
 
 Although this general division may be of 
 use in order to our proceeding more metho- 
 dically in our subject, we are not to under- 
 stand it as if, in those operations which are 
 ascribed to the understanding, there were 
 no exertion of will or activity, or as if the 
 understanding were not employed in the 
 operations ascribed to the will ; for I con- 
 ceive there is no operation of the under- 
 standing wherein the mind is not active in 
 some degree. We have some command 
 over our thoughts, and can attend to this 
 or to that, of many objects which present 
 themselves to our senses, to our memory, 
 or to our imagination. We can survey an 
 object on this side or that, superficially or 
 accurately, for a longer or a shorter time ; 
 so that our contemplative powers are under 
 the guidance and direction of the active ; 
 and the former never pursue their object 
 without being led and directed, urged or 
 restrained by the latter .- and because the 
 understanding is always more or less di- 
 rected by the will, mankind have ascribed 
 some degree of activity to [68] the mind in 
 its intellectual operations, as well as in those 
 which belong to the will, and have ex- 
 pressed them by active verb.s, such as see- 
 ing, hearing, judging, reasoning, and the 
 like. 
 
 And as the mind exerts some degree of 
 activity even in the operations of under- 
 standing, so it is certain that there can be 
 no act of will which is not accompanied 
 with some act of understanding- The wUl 
 must have an object, and that object must 
 be apprehended or conceived in the under- 
 standing. It is, therefore, to be remem- 
 bered, that, in most, if not all operations of 
 the mind, both faculties concur ; and we 
 range the operation under that faculty which 
 hath the largest share in it.* 
 
 The intellectual powers are commonly 
 divided into simple apprehension, judgment, 
 and reasoning. -f As this division has in 
 its favour the authority of antiquity, and of 
 a very general reception, it would be im- 
 proper to set it aside without giving any 
 reason : I shall, therefore, explain it briefly, 
 and give the reasons why I choose to follow 
 another. 
 
 • It should be always remembered that the various 
 mental energies are all only possible in and through 
 each other; and that our psychological analyses do not 
 suppose any leal distinction of the operations which 
 we discriminate by different name?. Thought and 
 volition can no more be exerted apart, than the sides 
 and angles of a square can exist separately from each 
 other.— H. 
 
 -f- This is a singular misapprehension. The divi. 
 sion in question, I make bold to sav, never was 
 proposed by any philosopher as a ptychological dis. 
 tribution of the cognitive faculties in general : on 
 the contrary, it is only a logical distribution of .that 
 section of the cognitive (acuities which we.denomi. 
 naXe discursive, &i those alone which are proximately 
 concerned in the process ot reasoning — or thought, in 
 ita strictest signification.- H. 
 
 [67, 68"]
 
 rilAP. 
 
 VII.] DIVISION OF THE I'UWERS OF THE MIND. 
 
 243 
 
 It may be observed that, without appre- 
 hension of the objects concerning which 
 we judge, there can be no judgment ; as 
 little can there be reasoning without buth 
 apprehension and judgment: these three 
 operations, therefore, are not independent 
 of each other. The second includes the 
 first, and the third includes both the first 
 and second ; but the first may be exer- 
 cised without either of the other two." It 
 is on that account called simple vppreh^n- 
 sion ; that is, apprehension unaccimpanicd 
 with any judgment about the object appre- 
 hended. This simple apprehension of an 
 object is, in common language, called having 
 a notiiii, or having a concepiiou of the ob- 
 ject, and by late authors is called having 
 an idea of it. In speaking, it is expressed 
 by a word, or by a part of a proposition, 
 without that composition and structure 
 which makes a complete sentence ; as a 
 man, a man of fortune. Such words, taken 
 by themselves, signify simple apprehen- 
 sions. They neither affirm nor [Oy] deny ; 
 they imply no judgment or opinion of the 
 thing signified by them ; and, therefore, 
 cannot be said to be either true or false. 
 
 The second operation in this division is 
 judgmeiil ; in which, say the philosophers, 
 there must be two objects of thought com- 
 pared, and some agreement or disagree- 
 ment, or, in general, some relation discerned 
 between them ; in consequence of which, 
 there is an opinion or belief of that relation 
 which we discern. This operation is ex- 
 pressed in speech by a proposition, in which 
 some relation between the things compared 
 is affirmed or denied : as when we say. All 
 men are fallible. 
 
 Truth and falsehood are qualities which 
 belong to judgment only ; (,r to proposi- 
 tions by which judgment is expressed. 
 Every judgment, every opinion, and every 
 proposition, is either true or false. But 
 words which neither affiini nor deny any- 
 thing, can have neither of those qualities ; 
 and the same may be said of simple a])prc- 
 hensions, which are signified by such words. 
 
 The third operation is reasoiiing ; in 
 wliieli, from two or more judgments, we 
 draw a conclusion. 
 
 This division of our intellectual powers 
 corresponds perfectly with the account com- 
 monly given by philosophers, of the suc- 
 cessive steps by which the mind proceeds 
 in the acquisition of its knowledge ; which 
 are these three : I'irst, By the senses, or 
 by other means, it is furnished with various 
 
 • 'nris is .not correct. Apprehension i« a- impn". 
 •ible witlioiit jiKl«iiicnt, ■■ s juilpincnl is mpd'HiMe 
 without apl)rihcnsio . The ;ip[iri lieii-ion of a thing 
 or notion, i» only realized in the iik titnl atliiinalloii 
 that llic conccfii ideally exists, and tlii? alliriiiation is 
 a judgtneiil. In (act, all eomiciou-^ncss HiJiiposes a 
 Juiigoient, as all consciotmncti tuppotcs a discriinina- 
 lion —11 
 
 [«y-7i 
 
 simple apprehensions, notions, or ideas. 
 These are the materials which nature gives 
 it to work upon ; and from the simple ideas 
 it is furnished with ly nature, it forms 
 various others n;ore complex. Secondly, 
 By comparing its ideas, and by perceivmg 
 their agreements and disagreements, it 
 ibims its judgments. And, Lastly, From 
 two or more judgii.ents, it deduces con- 
 clusions of reasoning. 
 
 iS'ow, if all our knowledge is got by a 
 procedure of this kind, [70] certainly the 
 threefold division of the powers of under- 
 standing, into simple apprehension, judg- 
 ment, and reasoning, is the most natural 
 and the most proper that can be devised. 
 This theory and tliat division are so closely 
 connected that it is difficult to judge which 
 of them has given rise to the other ; and 
 they must stand or fall together. But, if 
 ail our knowledge is not got by a process 
 of this kind — if there are other avenues 
 of knowledge besides the comparing our 
 ideas, and perceiving their agi cements and 
 disagreements — it is probable that there may 
 be operations of the understanding which 
 cannot be properly reduced under any of 
 the three that have been explained. 
 
 Let us consider some of the most familiar 
 operations of our minds, and see to which 
 of the three they belong. I begin with 
 consciousness. 1 know that I think, and 
 this of all knowledge us the most certain. 
 Is that operation of my mind which gives 
 me this certain knowledge, to be called 
 simple apprehension ? No, surely. Simple 
 apprehension neither affirms nor denies. 
 It will not be said that it is by reason- 
 ing that I know that I think. It re- 
 mains, therefore, that it must be by judg- 
 ment — that is, according to the account 
 given of judgment, by comparing two ideas, 
 and perceiving the agreement between 
 them. But what are the ideas compared ? 
 They must be the idea of myself, and the 
 ideji of thought, for they are the terms of 
 the proposition / think. According to this 
 account, then, first, I have the idea of my- 
 self and the idea of thought ; then, by com- 
 paring these two ideas, I perceive that I 
 think. 
 
 Let any man who is capable of reflection 
 judge for hhnself, whether it is by an opera- 
 tion of this kind that he conies to be con- 
 vinced that he thinks ? To me it appears 
 evident, that the conviction I have that I 
 think, is not got in this way ; and, therefore, 
 I conclude, either that consciousness is not 
 judgment, or that judgment is not rightly 
 defined to be the perception of some agree- 
 ment 0! disagreement between two id< as. 
 
 'J'ho percei)tion of an object by my 
 senses is another operation of 17' 1 the 
 understanding. 1 would know whetlier it 
 )je simple api)rehcn8ion, or judgment, or 
 
 It '2
 
 244 
 
 ON THE INTELLECTUAL POWERS. 
 
 reasoning. It is not simple apprehension, 
 because I am persuaded of the existence of 
 the object as much as I could be by demon- 
 stration. It is not judgment, if by judg- 
 ment be meant the comparing ideas, and 
 perceiving their agreements or disagree- 
 ments. It is not reasoning, because those 
 who cannot reason can perceive. 
 
 I find the same difficulty in classing me- 
 mory under any of the operations men- 
 tioned. 
 
 There is not a more fruitful source of 
 error in this branch of philosophy, than 
 divisions of things which are taken to be 
 complete when they are not really so. To 
 make a perfect division of any class of 
 things, a man ought to have the whole 
 under his view at once. But the greatest 
 capacity very often is not sufficient for 
 this. Something is left out which did not 
 come under the philosopher's view when 
 he made his division : and to suit this to 
 the division, it must be made what nature 
 never made it. This has been so common 
 a fault of philosophers, that one who would 
 avoid error ought to be suspicious of divi- 
 sions, though long received, and of great 
 authority, especially when they are grounded 
 on a theory that may be called in question. 
 In a subject imperfectly known, we ought 
 not to pretend to perfect divisions, but to 
 leave room for such additions or alterations 
 as a more perfect view of the subject may 
 afterwards suggest. 
 
 I shall not, therefore, attempt a com- 
 plete enumeration of the powers of the hu- 
 man understanding. I shall only mention 
 those which I propose to explain ; and they 
 are the following : — 
 
 Isf, The powers we have by means of 
 our external senses. 2dly, Memory. 3(%, 
 Conception. 4thli/, The powers of resolv- 
 ing and analysing complex objects, and 
 compounding those that are more simple. 
 blhly, Judging. Qthly, Reasoning, ^thly^ 
 Taste. Qthly, Moral Perception ;• and, last 
 of all, Consciousness.^ [72] 
 
 CHAPTER VIII. 
 
 OF SOCIAL OPERATIONS OF MIND. 
 
 There is another division of the powers 
 of the mind, which, though it has been, 
 ought not to be overlooked by writers on 
 this subject, because it has a real founda- 
 tion in nature. Some operations of our 
 minds, from their very nature, are social, 
 others are solitary. 
 
 * Moral Perception is treated under the Active 
 Powers, in Essay V.— H. 
 
 t Consciousness obtains only an incidental consi. 
 deration, under Judgment, in the Fifth Chapter of 
 the Sixth Essay.— H. 
 
 By the first, I understand such operations 
 as necessarily suppose an intercourse with 
 some other intelligent being. A man may 
 understand and will ; he may apprehend, 
 and judge, and reason, though he should 
 know of no intelligent being in the universe 
 besides himself. But, when he asks inform- 
 ation, or receives it ; when he bears tes- 
 timony, or receives the testimony of an- 
 other ; when he asks a favour, or accepts 
 one ; when he gives a command to his ser- 
 vant, or receives one from a superior ; when 
 he plights his faith in a promise or con- 
 tract — these are acts of social intercourse 
 between intelligent beings, and can have no 
 place in solitude. They suppose under- 
 standing and will ; but they suppose some- 
 thing more, which is neither understanding 
 nor will ; that is, society with other intelU» 
 gent beings. They may be called intellec- 
 tual, because they can only be in intellectual 
 beings; but they are neither simple appre- 
 hension, nor judgment, nor reasoning, nor are 
 they any combination of these operations. 
 
 To ask a question, is as simple an opera- 
 tion as to judge or to reason ; yet it is 
 neither judgment nor reasoning, nor simple 
 apprehension, nor is it any composition of 
 these. Testimony is neither simple appre- 
 hension, nor judgment, nor reasoning. The 
 same may be said of a promise, or of a con- 
 tract. These acts of mind are perfectly 
 imderstood by every man of common under- 
 standing ; but, when philosophers attempt 
 to bring them within the pale of their divi- 
 sions, by analysing them, they find inex- 
 plicable mysteries, [73] and even contradic- 
 tions, in them. One may see an instance 
 of this, of many that might be mentioned, 
 in Mr Hume's " Enquiry concerning the 
 Principles of Morals," § 3, part 2, note, 
 near the end. 
 
 Tlie attempts of philosophers to reduce 
 the social operations under the common 
 philosophical divisions, resemble very much 
 the attempts of some philosophers to re- 
 duce all our social affections to certain 
 modifications of self-love. The Author of 
 our being intended us to be social beings, 
 and has, for that end, given us social intel- 
 lectual powers, as well as social affections.* 
 Both are original parts of our constitution, 
 and the exertions of both no less natural 
 than the exertions of those powers that are 
 solitary and selfish. 
 
 Our social intellectual operations, as well 
 as our social affections, appear very early 
 in life, before we are capable of reasoning ; 
 yet both suppose a conviction of the exist- 
 ence of other intelligent beings. When a 
 child asks a question of his nurse, this act 
 
 • " Man," says Aristotle, " is, by nature, mere 
 political than any bee or ant." And, in another 
 work, " Man is the sweetest thing to man"— i»9{^. 
 
 WW vj^ts'611 olvS^uircf — H. 
 
 1 T2, 73]
 
 CHAP. VIII 
 
 ■] 
 
 OF SOCIAL OPERATIONS OF iMlXD. 
 
 245 
 
 of his mind supposes not only a desire to 
 know what he asks ; it supposes, likewise, 
 a conviction tliat the nurse is an intelligent 
 being, to wlioin he can communicate his 
 thoughts, and who can communicate her 
 thoughts to him. How he came by this 
 conviction so early, Ls a question of some 
 importance in the knowledge of the human 
 mind, and, therefore, worthy of the con- 
 sideration of philosophers. But they seem 
 to liave given no attention, either to this 
 early conviction, or to those operations of 
 mind which suppose it. Of this we shall 
 Lave occasion to treat afterwards. 
 
 All languages are fitted to express the 
 social as well as the solitary operations of 
 the mind. It may indeed be affirmed, that, 
 to express the former, is the prmiary and 
 direct intention of language. A man who 
 had no intercourse with any other intelli- 
 gent being, would never think of language. 
 He would be as mute as the beasts of the 
 field ; even more so, because they have 
 some degree of social intercourse with one 
 another, and some of them [74] with man. 
 AV'hen language is once learned, it may be 
 useful even in our solitary meditations ; and 
 by clothing our thoughts with words, we 
 may have a firmer hold of them. But 
 this was not its first intention ; and the 
 structure of every language shews that it is 
 not intended solely for this purpose. 
 
 In every language, a question, a com- 
 mand, a promise, which are social acts, can 
 be expressed as easily and as properly as 
 judgment, which is a solitary act. The ex- 
 pression of the last lias been honoured with 
 a particular name ; it is called a proposition ; 
 it has been an object of great attention to I 
 
 philosophers ; it has been analysed into its 
 very elements of subject predicate, and co- 
 pula. All the various modifications of these, 
 and of propositions which are compounded of 
 them, have been anxiously examined in 
 many voluminous tracts. The expression 
 of a question, of a command, or of a pro- 
 mise, is as capable of being analysed as a 
 proposition is ; but we do not find" that this 
 has been attempted ; we have not so much 
 as given them a name different from the 
 operations which they express. 
 
 Why have speculative men laboured so 
 anxiously to analyse our solitary operations, 
 and given so little attention to the social ? 
 I know no other reason but this, that, in 
 the divisions that have been made of the 
 mind's operations, the social have been 
 omitted, and thereby thrown behind the 
 curtain. 
 
 In all languages, the second person of 
 verbs, the pronoun of the second person, and 
 the vocative case in nouns, are appropriated 
 to the expression of social operations of mind, 
 and could never have had place in language 
 but for this purpose : nor is it a good 
 argument against this observation, that, by 
 a rhetorical figure, we sometimes address 
 persons that are absent, or even inanimated 
 beings, in the second person. For it ought 
 to be remembered, that all figurative ways 
 of using words or phrases suppose a natural 
 and literal meaning of them.* [75] 
 
 * What, throughout this chapter, is implied, ought 
 to have been explicitly stated — that language is natu. 
 ral to man ; and consequently the faculty of speech 
 ought to have been enumerated among the mental 
 powers. — H. 
 
 ESSAY II. 
 
 OF THE POWERS WE HAVE BY MEANS OF OUR 
 EXTERNAL SENSES. 
 
 CHAPTER I. 
 
 OF THE ORGANS OF SENSE. 
 
 Of all the operations of our minds, the 
 perception of external objects is the most 
 familiar. The senses come to maturity 
 even in infancy, when other powers have 
 not yet fii)rung u|i. They are common to 
 us with Ijrute animals, and furnish us with 
 tlie objects about wliich our other powers 
 are the most frequently employed. We 
 find it easy to attend to their operations; 
 and, because they are familiar, the nanies 
 which properly belong to them are ap[>licd 
 l_7i, 75] 
 
 to other powers which are thought to re- 
 semble them. For these reasons, they claim 
 to be first considered. 
 
 The perception of external objects is one 
 main link of that mysterious chain which 
 connects the material world with the intel- 
 lectual. We shall fiiul many things in this 
 operation unaccountaitle ; sufficient to con- 
 vince us that we know but little of our own 
 frame; and that a perfect c<iin])rchension 
 of our mental powers, ami of the manner of 
 their operation, is beyond the reach of our 
 understanding. 
 
 In perception, there are impressions upon 
 tlie organs of boiibc, the nerves, and braii>
 
 246 
 
 ON THE INTELLECTUAL POWERS. 
 
 [»^ 
 
 SSAY II, 
 
 which, by the laws of our nature, are fol- 
 lowed by certain operations of mind. These 
 two things are apt to be confounded ; but 
 ought most carefully to be distinguished. 
 Some philosophers, without good reason, 
 have concluded, that the [76] impressions 
 made on the body are the proper efficient 
 cause of perception. Others, with as little 
 reason, have concluded that impressions are 
 made on the mind similar to those made on 
 the body. From these mistakes many others 
 have arisen. The wrong notions men have 
 rashly taken up with regard to the senses, 
 have led to wrong notions with regard to 
 other powers which are conceived to resemble 
 them. Many important powers of mind 
 have, especially of late, been called internal 
 senses, from a supposed resemblance to the 
 external — such as, the sense of beauty, the 
 sense of harmony, the moral sense.* And 
 it is to be apprehended that errors, v^ith 
 regard to the external, have, from analogy, 
 led to similar errors with regard to the 
 internal ; it is, therefore, of some conse- 
 quence, even with regard to other branches 
 of our subject, to have just notions concern- 
 ing the external senses. 
 
 In order to this, we shall begin with some 
 observations on the organs of sense, and on 
 the impressions which in perception are 
 made upon them, and upon the nerves and 
 brain. 
 
 IVe perceive no external object but by 
 means of certain bodily organs which God 
 has given us for that purpose. The Su- 
 preme Being who made us, and placed us 
 in this world, hath given us such powers of 
 mind as he saw to be suited to our state 
 and rank in his creation. He has given us 
 the power of perceiving many objects around 
 us — the sun, moon, and stars, the earth and 
 sea, and a variety of animals, vegetables, 
 and inanimate bodies. But our power of 
 perceiving these objects is limited in various 
 ways, and particularly in this — that, with- 
 out the organs of the several senses, we 
 perceive no external object. We cannot 
 see without eyes, nor hear without ears ; it 
 is not only necessary that we should have 
 these organs, but that they should be in a 
 sound and natural state. There are many 
 disorders of the eye that cause total blind- 
 ness ; others that impair the powers of vi- 
 sion, without destroying it altogether : and 
 the same may be said of the organs of all 
 the other senses. [77] 
 
 AU this is so well known from experience, 
 that it needs no proof; but it ought to be 
 observed, that we know it from experience 
 only. We can give no reason for it, but 
 that such is the will of our Maker. No 
 man can shew it to be impossible to the 
 Supreme Being to have given us the power of 
 
 • He rffers to Hutcheson.— H 
 
 perceiving external objects without such or- 
 gans.* We have reason to believe that, when 
 we put off these bodies and all the organs 
 belonging to them, our perceptive powers 
 shall rather be improved than destroyed or 
 impaired. We have reason to believe that 
 the Supreme Being perceives everything in 
 a much more perfect manner than we do, 
 without bodily organs. We have reason to 
 believe that there are other created beings 
 endowed with powers of perception more 
 perfect and more extensive than ours, with- 
 out any such organs as we find necessary. 
 
 We ought not, therefore, to conclude, 
 that such bodily organs are, in their own 
 nature, necessary to perception ; but rather 
 that, by the will of God, our power of per- 
 ceiving external objects is limited and cir- 
 cumscribed by our organs of sense ; so that 
 we perceive objects in a certain manner, 
 and in certain circumstances, and in no 
 other. -j- 
 
 If a man was shut up in a dark room, so 
 that he could see nothing but through one 
 small hole in the shutter of a window, 
 would he conclude that the hole was the 
 cause of his seeing, and that it is impos- 
 sible to see any other way ? Perhaps, if he 
 had never in his life seen but in this way, 
 he might be apt to think so; but the con- 
 clusion is rash and groundless. He sees, 
 because God has given him the power of 
 seeing ; and he sees only through this small 
 hole, because his power of seeing is circum- 
 scribed by impediments on all other hands. 
 
 Another necessary caution in this matter 
 is, that we ought not to confound the or- 
 gans of perception with the being that per- 
 ceives. Perception must be the act of some 
 being that perceives. The eye [78] is not 
 that which sees ; it is only the organ by which 
 we see.^: The ear is not that which hears, 
 but the organ by which we hear ; and so of 
 the rest. § 
 
 A man cannot see the satellites of Jupiter 
 but by a telescope. Does he conclude from 
 tJiis, that it is the telescope that sees those 
 stars ? By no means — such a conclusion 
 would be absurd. It is no less absurd to 
 
 * However astonishing, it is now proved beyond 
 all rational doubt, that, in certain abnormal states 
 of the nervous organism, perceptions are possible, 
 through other than the ordinary channels of the 
 senses. — H 
 
 + The doctrine of Plato and of m.-iiiy other phi. 
 lojophers. Reid ought, however, to have saiil, 
 limited to, instead of " by our organs of sense :'• for, 
 if the body be viewed as the prison of the soul, the 
 senses must be viewed at least as partial outlets. — 
 H. 
 
 t ^1 e(p9aXfj.Sv, 'ii;t o(}6xXju.e7( , 8ay« Plato, followed 
 by a host ot philosophers, comparing the tienscs to 
 windows of the mind. — H. 
 
 5 ' I he mind fees," says Epicharmus — " the mind 
 hears, all else is deaf and blind" — a saying alluded to 
 a.^ proverbial by Aristotle, in a passage to the same 
 effect, which cannot adequately lie translated :— - 
 'X.u^icOitaa, uiffOv.a-ii iiecvctxi, xtx.6aiT(( avxitrfiriTOf 
 Tovov s^iff ua-ti^ Ei^trr^i to, Nv; o^oi^ x oti *i f 
 i. X oi 11- This has escipc'd the commentaiors. — H. 
 Seep. 87S,n. f7(;_78'|
 
 CHAP. II.] OF IMPRESSIOiNS ON THE ORGANS, &c. 
 
 247 
 
 conclude that it is the eye that sees, or 
 the ear tliat hears. The telescope is an 
 artificial organ of sight, but it sees not- 
 The eye is a natural organ of sight, by 
 which we see ; but the natural organ sees 
 as little as the artificial. 
 
 The eye is a machine nmet admirably 
 contrived for refracting the rays of light, 
 and forming a distinct picture of objects 
 upon the retina ; but it sees neither the 
 object nor the picture. It can form the 
 picture after it is taken out of the head ; 
 but no vision ensues. Even when it is in 
 its proper place, and perfectly sound, it is 
 well known that an obstruction in the optic 
 nerve takes away vision, though the eye 
 has performed all that bel'^ngs to ie. 
 
 If anything more were necessary to be 
 said on a point so evident, we might ob- 
 serve that, if the faculty of seeing were in 
 the eye, that of hearing in tlie ear, and so 
 of the other se ses, the necessary conse- 
 quence of this would be, that the thinking 
 principle, which I call myself, is not one, 
 but many. But this is contrary to the ir- 
 resistible conviction of every man. When 
 I say I see, I hear, I feel, I remember, 
 this implies that it is one and the same self 
 that performs all these operations ; and, as 
 it would be absurd to say that my memory, 
 another man's imagination, and a third 
 man's reason, may make one individual 
 intelligent being, it would be equally ab- 
 surd to say that one piece of matter see- 
 ing, another hearing, and a third feeling, 
 may make one and the same percipient 
 being. 
 
 These sentiments are not new ; they have 
 occurred to thinking men from early ages. 
 Cicero, in his " Tusculan Questions," Book 
 I., chap. 20, has expressed them very dis- 
 tinctly. Those who choose may consult the 
 passage," [79] 
 
 CHAPTER II. 
 
 OFTHE IMPRESSIONS ON THB ORGANS, NBRVKS, 
 AND BRAINS. 
 
 A SECOND law of our nature regarding 
 perception is, Ihat tee perceive no object, 
 vn'ess some impression is made upon the 
 orjjan of sense, ei'hrr }iy the immediate 
 application of the. oliject, or by some medium 
 which passes between the object anil the 
 orr/an. 
 
 In two of our senses — to wit, tovch and 
 t.iste — there must be an immediate applica- 
 tion of the object to the organ. In tlie 
 other three, the object is perceived at a dis- 
 tance, but still by means of a medium, by 
 
 • C'ircro «iiyB ni.thitiR on (hii lirad that had not 
 been taid bcTore him by ilie Gicck iihllr'tojilicrt — H. 
 
 [79, 80] 
 
 which some impression is made upon the 
 organ. * 
 
 The effluvia of bodies drawn into the 
 nostrils with the breath, are the medium of 
 smell ; the undulations of the air are the 
 medium of hearing ; and the rays of ligh 
 passing from visible objects to the eye, ar 
 the medium of sight. We see no object 
 unless rays of light come from it to the eye. 
 We hear not the sound of any body, unless 
 the vibrations of some elastic medium, oc- 
 casioned by the tremulous motion of the 
 sounding body, reach our ear. We per- 
 ceive no smell, unless the effluvia of the 
 smelling body enter into the nostrils. We 
 perceive no taste, unless the sapid body be 
 applied to the tongue, or some part of the 
 organ of taste. Nor do we perceive any 
 tangible quality of a body, unless it touch 
 the hands, or some part c« our bodies. 
 
 These are facts known from experience 
 to hold universally and invariably, both in 
 men and brutes. By this law of our na- 
 ture, our powers of perceiving external ob- 
 jects, are farther limited and circumscribed. 
 Nor can we give any other reason for this, 
 than [80] that it is the will of our INIaker, who 
 knows best what powers, and what degrees 
 of them, are suited to our state. We were 
 once in a state, I mean in the womb, wherein 
 our powers of perception were more limited 
 than in the present, and, in a future state, 
 they may be more enlarged. 
 
 It is likewise a law of our nature, that, 
 in order to our perceiving objects, the im- 
 pressions made upon the organs of sense 
 must be communicated to the nerves, and 
 by them to the brain. This is perfectly 
 known to those who know anything of ana- 
 tomy. 
 
 The nerves are fine cords, which pass 
 from the brain, or from the spinal marrow, 
 which is a production of the brain, to all 
 parts of the body, dividiiig into smaller 
 branches as they proceed, until at last they 
 escape our eyesight : and it is found by 
 experience, that all the voluntary and in- 
 voluntary motions of the body are performed 
 by their means. When the nerves that 
 serve any limb, are cut, or tied hard, we 
 have then no more power to move that limb 
 than if it was no part of the body. 
 
 As there are nerves that serve the mus- 
 cular motions, so there are others that serve 
 the several senses ; and as without the for- 
 mer we cannot move a limb, so without the 
 latter we can liave no perception. 
 
 • Thi« distinction of a mediate and ininicdialt olv 
 )ect, or of an object and u niediuni, in iiercciJtion, ii 
 inaccurate, and a source of sad confuson. \Ve per. 
 ceivc. and can perceive, nothing but what is in rela- 
 tioii to tlie or^-an, and notllln^: is in relation to tlio 
 orfc.in that is nut prCKcnl to it. All Ihefciises are, in 
 (act. modilicatii-m of touch, as Dcn^criiui of old 
 tauxhl. We rench the distant reality, not I'y »cn»e. 
 not by perception, but by inlerence. llciil, how. 
 ever, in thii only follows liii prrdecciiort — ii.
 
 248 
 
 ON THE INTELLECTUAL POWERS. 
 
 [essay II. 
 
 This train of macliiuery the wisdom of 
 God has made necessary to our perceiving 
 objects. Various parts of tlie body concur 
 to it, and each has its own function. First, 
 The object, either immediately, or by some 
 medium, must make an impression on the 
 organ. The organ serves only as a medium 
 by which an impression is made on the 
 nerve ; and the nerve serves as a medium 
 to make an impression upon the brain. 
 Here the material part ends ; at least we 
 can trace it no farther ; the rest is all in- 
 tellectual." 
 
 The proof of these impressions upon the 
 nerves and brain in [81] perception is this, 
 that, from many observations and experi- 
 ments, it is found that, when the organ of 
 any sense is perfectly sound, and has the 
 impression made upon it by the object ever 
 so strongly, yet, if the nerve which serves 
 that organ be cut or tied hard, there is no 
 perception ; and it is well known that dis- 
 orders in the brain deprive us of the power 
 of perception when both the organ and its 
 nerve are sound. 
 
 There is, therefore, sufficient reason to 
 conclude that, in perception, the object pro- 
 duces some change in the organ ; that the 
 organ produces some change upon the 
 nerve ; and that the nerve produces some 
 change in the brain. And we give the 
 name of an impression to those changes, 
 because we have not a name more proper to 
 express, in a general manner, any change 
 produced in a body, by an external cause, 
 without specifying the nature of that 
 change. Whether it be pressure, or at- 
 traction, or repulsion, or vibration, or some- 
 thing unknown, for which we have no 
 name, still it may be called an impression. 
 But, with regard to the particular kind of 
 this change or impression, philosophers 
 have never heen able to discover anything 
 at all. 
 
 But, whatever be the nature of those im- 
 pressions upon the organs, nerves, and 
 brain, we perceive nothing without them. 
 Experience informs that it is so ; but we 
 cannot give a reason why it is so. In the 
 constitution of man, perception, by fixed 
 laws of nature, is connected with those im- 
 pressions ; but we can discover no neces- 
 sary connection. The Supreme Being has 
 seen fit to limit our power of perception ; so 
 that we perceive not without such impres- 
 sions; and this is aU we know of the 
 matter. 
 
 This, however, we have reason to con- 
 
 • There can be no doubt that the whole organism 
 of the sense, from periphery to centre, must co-operate 
 simultaneously in perception ; but there is no rea. 
 son to place the mind at the central extremity alone, 
 and to hold that not only a certain series of organic 
 changes, but a sensation, must precede the mental 
 cognition. This is mere hypothesis, and oppoaed to 
 the testimony of cOiisciousness. — K. 
 
 elude in general — that, as the impressions on 
 the organs, nerves, and brain, correspond 
 exactly to the nature and conditions of the 
 objects by which they are made, so our 
 perceptions and sensations correspond to 
 those impressions, and vary in kind, and in 
 degree, as they vary. [82] Without this exact 
 correspondence, the information we receive 
 by our senses would not only be imperfect, 
 as it undoubtedly is, but would be fallacious, 
 which we have no reason to think it is. 
 
 CHAPTER in. 
 
 HYPOTHESES CONCERNING THE NERVES AND 
 BRAIN. 
 
 We are informed by anatomists, that, al- 
 though the two coats which inclose a nerve, 
 and which it derives from the coats of the 
 brain, are tough and elastic, yet the nerve 
 itself has a very small degree of consistence, 
 being almost like marrow. It has, how- 
 ever, a fibrous texture, and may be divided 
 and subdivided, till its fibres escape our 
 senses ; and, as we know so very little about 
 the texture of the nerves, there is great 
 room left for those who choose to indulge 
 themselves in conjecture. 
 
 The ancients conjectured that the ner- 
 vous fibres are fine tubes, filled with a very 
 subtile spirit, or vapour, which they called 
 animal spirits ; that the brain is a gland, 
 by which the animal spirits are secreted 
 from the finer part of tlie blood, and their 
 continual waste repaired ; and that it is by 
 these animal spirits that the nerves perform 
 their functions. Des Cartes has shewn 
 how, by these animal spirits, going and re- 
 turning in the nerves, muscular motion, 
 perception, memory, and imagination, are 
 efiected. All this he has described as dis- 
 tinctly as if he had been an eye-witness of 
 all those operations. But it happens that 
 the tubular structure of the nerves was 
 never perceived by the human eye, nor 
 shewn by the nicest injections ; and all that 
 has been said about animal spirits, through 
 more than fifteen centuries, is mere con- 
 jecture. 
 
 Dr Briggs, who was Sir Isaac Newton's 
 master in anatomy, was the first, as far as 
 I know, who advanced a new system 
 concerning [83] the nerves." He conceived 
 them to be solid filaments of prodigious 
 
 " Briggs was not the first. The Jesuit, Hon'-, 
 ratus Fabry, had before him denied the old hypothe- 
 cs of spirits ; and the new hypothesis of cerebral 
 fibres, and fibrils, by which he explains the phaeno. 
 meiia of senie, imagination and memory, is not on'y 
 the first, but perhaps the most ingenious of the class 
 tliat has been proposed. Yet the very name of Fabry 
 is wholly unnoticed by those historians of philosopliy 
 who do not deem it superflucus to dwell on the tire 
 some reveries of Briggs, Hartley, and Bonnet. — H. 
 
 [81_S3]
 
 CHAP. III.] HYPOTHESES CONCERNING THE NERVES, &c. 249 
 
 tenuity ; and this opinion, as it accords bet- 
 ter with observation, seems to have been 
 more generally received since his time. As 
 to the manner of performing their office, 
 Dr Briggs thought that, like musical cords, 
 they have vibrations differing according to 
 their length and tension. They seem, how- 
 ever, very unfit for this purpose, on account 
 of their want of tanacity, their moisture, 
 and being through their whole length in 
 contact with moist substances ; so that, al- 
 though Dr Briggs wrote a book upon this 
 system, called Nova Visionis Theoria, it 
 seems not to have been much followed. 
 
 Sir Isaac Newton, in all his philosophical 
 writings, took great care to distinguish his 
 doctrines, which he pretended to prove by 
 just induction, from his conjectures, which 
 were to stand or fall according as future 
 experiments and observations should esta- 
 blish or refute them. His conjectures he 
 has put in the form of queries, that they 
 might not be received as truths, but be 
 inquired into, and determined according to 
 the evidence to be found for or against 
 them. Those who mistake his queries for 
 a part of his doctrine, do him great injus- 
 tice, and degrade him to the rank of the 
 common herd of philosophers, who have in 
 all ages adulterated philosophy, by mixing 
 conjecture with truth, and their own fancies 
 with the oracles of Nature. Among other 
 queries, this truly great philosopher pro- 
 posed this, AVhether there may not be an 
 elastic medium, or aether, immensely more 
 rare than air, which pervades all bodies, 
 and which is the cause of gravitation ; of 
 the refraction and reflection of the rays of 
 light ; of the transmission of heat, through 
 spaces void of air ; and of many other phaa- 
 nomena ? In the 23d query subjoined to his 
 "Optics," he puts this question with regard 
 to the impressions made on the nerves and 
 brain in perception, Wliether vision is 
 effected chiefly by the vibrations of this 
 medium, excited in the bottom of the eye 
 by the rays of light, and propagated along 
 the solid, pellucid, and uniform capillaments 
 of the optic nerve ? And whether liearing 
 is effected [84] by the vibrations of this or 
 some other medium, excited by the tremor 
 of the air in the auditory nerves, and pro- 
 pagated along the solid, pellucid, and uni- 
 form capillaments of those nerves ? And 
 so with regard to the other senses. 
 
 What Newton only proposed as a matter 
 to be inquired into, Dr Hartley conceived 
 to have such evidence, that, in liis " Ob- 
 servations on IVIan," he has deduced, in a 
 mathematical form, a very ainjtle system 
 concerning the faculties of the mind, from 
 the doctrine of vibrations, joined with that 
 of association. 
 
 His notion of the vibrations excite<l in 
 the nerves, ia expressed in Propositions 4 
 [8i, 85] 
 
 and 5 of the first part of his " Observa- 
 tions on Man." "Prop. 4. External objects 
 impressed ou the senses occasion, first in 
 the nerves on which they are impressed, 
 and then in the brain, vibrations of the 
 small, and, as one may say, infinitesimal 
 medullary particles. Prop. 5. The vibra- 
 tions mentioned in the last proposition are 
 excited, propagated, and kept up, partly by 
 the aether — that is, by a very subliJe elastic 
 fluid ; partly by the uniformity, continuity, 
 softness, and active powers of the medullary 
 substance of the brain, spinal marrow, and 
 nerves." 
 
 The modesty and diffidence with which 
 Dr Hartley offers his system to the world — 
 by desiring his reader " to expect nothing 
 but hints and conjectures in difficult and 
 obscure matters, and a short detail of the 
 principal reasons and evidences in those 
 that are clear ; by acknowledging, that he 
 shall not be able to execute, with any ac- 
 curacy, the proper method of philosophising, 
 recommended and followed by Sir Isaac 
 Newton ; and that he will attempt a sketch 
 ouly for the benefit of future enquirers" — 
 seem to forbid any criticism upon it. One 
 cannot, without reluctance, criticise what is 
 proposed in such a manner, and with so 
 good intention ; yet, as the tendency of this 
 system of vibrations is to make all the oper- 
 ations of the mind mere mechanism, depend- 
 ent [85] on the laws of matter and motion, 
 and, as it has been held forth by its vota- 
 ries, as in a manner demonstrated, I shall 
 make some remarks on that part of the sys- 
 tem which relates to the impressions made 
 on the nerves and brain in perception. 
 
 It may be observed, in general, that Dr 
 Hartley's work consists of a chain of pro- 
 positions, with their proofs and corollaries, 
 digested in good order, and in a scientific 
 form. A great jjart of them, however, are, 
 as ho candidly acknowledges, conjectures 
 and hints only ; yet these are mixed with 
 the propositions legitimately proved, with- 
 out any distinction. Corollaries are drawn 
 from them, and other propositions grounded 
 upon them, which, all taken together, make 
 iq) a system. A system of this kind re- 
 sembles a chain, of which some links are 
 abundantly strong, others very weak. The 
 strength of the chain is determined by that 
 of the weakest links ; for, if they give way, 
 the whole falls to pieces, and the weight 
 supi)ortcd by it falls to the ground. 
 
 Philosojihy has been, in all ages, adul- 
 tenited by hypotheses; that is, by systems 
 built partly on facts, and miicii u])on con- 
 jecture. It is pity that a man of Dr Hart- 
 ley's knowledge anil candour should have 
 followed the multitude in this fallacious 
 tract, after expressing his approbation of 
 the pro|)er method of pliilosophising, pointed 
 out liv Bacon and Newton. The last cim-
 
 250 
 
 ON THE INTELLECTUAL POWERS. 
 
 [essa y 
 
 Bidered it as a reproach when liis system 
 was called his hypothesis ; and says, with 
 disdain of such imputation, Hypotheses nou 
 Jingo. And it is very strange that Dr 
 Hartley should not only follow such a me- 
 thod of philosophising himself, but that he 
 sliould direct others in their inquiries to 
 follow it. So he does in Proposition 87, 
 Part I., where he deduces rules for the 
 ascertainment of truth, from the rule of 
 false, in arithmetic, and from the art of 
 decyphering ; and in other places. 
 
 As to the vibrations and vibratiuncles, 
 whether of an elastic aether, or of the in- 
 finitesimal particles of the brain and nerves, 
 there [86] may be such things for wliat we 
 know ; and men m:iy rationally inquire 
 whether they can find any evidence of their 
 existence ; but, while we have no proof of 
 their existence, to apply them to the solu- 
 tion of phsenomena, and to build a system 
 upon them, is what I conceive we call build- 
 ing a castle in the air. 
 
 When men pretend to account for any 
 of the operations of Nature, the causes 
 assigned by them ought, as Sir Isaac New- 
 ton has taught us, to have two conditions, 
 otherwise they are good for nothing. First, 
 Tiiey ought to be true, to have a real exist- 
 ence, and not to be barely conjectured to 
 exist, without proof. Secondly, They ought 
 to be sufficient to produce the effect. 
 
 As to the existence of vibratory motions 
 in the medullary substance of the nerves 
 and brain, the evidence produced is this : 
 First, It is observed that the sensations of 
 seeing and hearing, and some sensations of 
 touch, have some short duration and con- 
 tinuance. Secondly, Though there be no 
 direct evidence that the sensations of taste 
 and smell, and the greater part of these of 
 touch, have the like continuance, yet, says 
 the author, analogy would incline one to 
 believe that they must resemble the sensa- 
 tions of sight and hearing in this particular. 
 Thirdly, The continuance of all our sensa- 
 tions being thus established, it follows, that 
 external objects impress vibratory motions 
 on the medullary substance of the nerves 
 and brain ; because no motion, besides a 
 vibratory one, can reside in any part for a 
 moment of time. 
 
 This is the chain of proof, in which the 
 first link is strong, being confirmed by ex- 
 perience ; the second is very weak ; and the 
 third still weaker. For other kinds of mo- 
 tion, besides that of vibration, may have 
 some continuance — such as rotation, bending 
 or unbending of a spring, and perhaps others 
 which we are unacquahited with ; nor do 
 we know whether it is motion that is pro- 
 duced in the nerves — it may be pressure, 
 attraction, repulsion, or something we do 
 not know. This, indeed, is the common 
 refuge of all hypotheses, [87] that we know 
 
 no other way in which the phsenomena may 
 be produced, and, therefore, they must be 
 produced in this «ay. There is, "therefore, 
 no proof of vibrations in the infinitesimal 
 particles of the brain and nerves. 
 
 It may be thought that the existence of 
 an elastic vibrating aether stands on a firmer 
 foundation, having the authority of Sir 
 Isaac Newton. But it ought to be observed 
 that, although this great man had formed 
 conjectures about this aether near fifty 
 years before he died, and had it in his eye 
 during that long space as a subject of in- 
 quiry, yet it does not appear that he ever 
 found any convincing proof of its existence, 
 but considered it to the last as a question 
 whether there be such an aether or not. 
 In the premonition to the reader, prefixed 
 to the s-econd edition of his " Optics," 
 anno 1717, he expresses himself thus with 
 regard to it :— " Lest any one should think 
 that I place gravity among the essential 
 properties of bodies, I have subjoined one 
 question concerning its cause ; a question, 
 I say, for I do not hold it as a thing estab- 
 lished." If, therefore, we regard the 
 authority of Sir Isaac Newton, we ought 
 to hold the existence of such an aether as a 
 matter not established by proof, but to be 
 examined into by experiments ; and I have 
 never heard that, since his time, any new 
 evidence has been found of its existence. 
 
 " But," says Dr Hartley, " supposing 
 the existence of the aether, and of its pro- 
 perties, to be destitute of all direct evidence, 
 still, if it serves to account for a great 
 variety of phaenomena, it will have an in- 
 direct evidence in its favour by this means." 
 There never was an hypothesis invented by 
 an ingenious man which has not this evi- 
 dence in its favour. The vortices of Des 
 Cartes, the sylphs and gnomes of Mr Pope, 
 serve to account for a great variety of 
 phaenomena. 
 
 When a man has, with labour and in- 
 genuity, wrought up an hypothesis into a 
 system, he contracts a fondness for it, 
 which is apt [88] to warp the best judgment. 
 This, I humbly think, appears remarkably 
 in Dr Hartley. In his preface, he declares 
 his approbation of the method of philoso- 
 phising recommended and followed by Sir 
 Isaac Newton ; but, having first deviated 
 from this method in his practice, he is 
 brought at last to justify this deviation in 
 theory, and to bring arguments in defence 
 of a method diametrically opposite to it. 
 " We admit," says he, " the key of a cypher 
 to be a true one when it explains the cypher 
 completely." I answer. To find the key 
 requires an understanding equal or supe- 
 rior to that which made the cypher. This 
 instance, therefore, will then be in point, 
 when he who attempts to decypher the 
 works of Nature by an hypothesis, has an 
 
 [86-881
 
 ciiAP. 111.] HYPOTHESES CONCERNING THE NERVES, &c. 251 
 
 understanding equal or superior to that 
 whicli made tliem. The votaries of hypo- 
 theses have often been challenged to shew 
 one useful discovery in the works of Nature 
 that was ever made in that way. If in- 
 stances of this kind could be produced, we 
 ought to concluae that Lord Bacon and 
 Sir Isaac Newton have done great disser- 
 vice to philosophy by what they have said 
 against hypotheses. But, if no such in- 
 stance can be produced, we must conclude, 
 with those great men, that every system 
 which pretends to account for the phseuo- 
 mena of Nature by hypotlieses or conjecture, 
 is spurious and illegitimate, and serves only 
 to llatter the pride of man with a vain con- 
 ceit of Icnowledge which he has not attained. 
 
 The author tells us, "that any hypo- 
 thesis that has so much plausibility as to 
 explain a considerable number of facts, helps 
 us to digest these f;\cts in proper order, to 
 bring new ones to light, and to make es- 
 perimenta crucis for the sake of future 
 inquirers." 
 
 Let hypotlieses be put to any of these 
 uses as far as they can serve. Let them 
 suggest experiments, ordirect our inquiries ; 
 but let just induction alone govern our 
 belief. 
 
 " The rule of false affords an obvious and 
 strong instance of the possibilityof being led, 
 with precision and certainty, to a [89] true 
 conclusion from a false position. And it is 
 of the very essence of algebra to proceed in 
 the way of supposition." 
 
 This is true ; but, when brought to jus- 
 tify the accounting for natural phajnomena 
 by hypotheses, is foreiirn to the purpose. 
 When an unknown number, or any un- 
 known quantity, is sought, which must have 
 certain conditions, it may be found in a 
 scientific manner by the rule of false, or 
 by an algebraical analysis ; and, when 
 found, may be synthetically demonstrated 
 to be the numbo* or the quantity sought, 
 by its answering all the conditions required. 
 But it is one thing to find a quantity which 
 shall have certain conditions ; it is a very 
 different thing to find out the laws by whicli 
 it jileases Cod to govern the world and 
 produce the pi scnoiiicna which fall under 
 our observation. And we can then only 
 allow some weight to thisargiinient in favdui- 
 of hypotheses, when it can be shewn that 
 the cause of any one pliienomenon in nature 
 lias been, or can be found, as an unknown 
 quantity is, by the rule of fals(!, or by alge- 
 braical analysis. This, I aj)preluii(l, will 
 never be, till the lera arrives, which Dr 
 Hartley seems to foretell, " When future 
 generations shall put all kinds of evidences 
 and enquiries into matlieniatical forms; 
 and, as it were, reduce Aristotle's ten Ca- 
 tegories, and Bishop Wilkin's forty Sumvia 
 Iji'tirrii to the bead (if q'.iaiitilv alone, so as 
 fSf), 90] 
 
 to make mathematics and logic, natural 
 history aud civil history, natural philoso- 
 phy and philosophy of all other kinds, 
 coincide oiinii ix par/c.^' 
 
 Since Sir Isaac Newton laid down the 
 rules of philosophising in our inquiries into 
 the works of Nature, many philosophers 
 have deviated from them in practice ; per- 
 haps few have paid that regard to them 
 which they deserve. But they have met 
 with very general approbation, as being 
 founded in reason, and pointing out the 
 only path to the knowledge of Nature's 
 works. Dr Hartley is the only author I 
 have met with vlio reasons against them, 
 and has taken p.ains to find out arguments 
 in defence of the exploded method of hy- 
 pothesis. [90] 
 
 Another condition which Sir Isaac New- 
 ton requires in the causes of natural things 
 assigned by philosophers, is, that they be 
 sufficient to account for the phajnoniena. 
 Vibrations, aud vibratiuncles of the me- 
 dullary substance of the nerves and brain, 
 are assigned by Dr Hartley to account for 
 all our sensations and ideas, and, in a word, 
 for all the operations of our minds. Let 
 us consider very briefly how far they are 
 sufficient for that purpose. 
 
 It would be injustice to this author to 
 conceive him a materialist. He proposes 
 his sentiments with great candour, and they 
 ought not to be carried beyond what his 
 words express. He thinks it a consequence 
 of his theory, that matter, if it can be 
 endued with the most simple kinds of sens- 
 ation, might arrive at all that intelligence 
 of ■which the human niind is possessed. 
 He thinks that his theory overturns all 
 the arguments that are usually brought for 
 the immateriality of the soul, from the 
 subtilty of the internal senses, and of the 
 rational faculty ; but he docs not take upon 
 liiiii to determine whether matter can be 
 endued with sensation or no. He even 
 acknowledges that matter and motion, 
 however subtilly divided and reasoned u]ion, 
 J ield nothing more than nmtter and motion 
 still ; and therefore he would not be any 
 way interpreted so as to oppose the imma- 
 teriality of the soul. 
 
 Jt would, therefore, be imreasonable to 
 require that his theory of vibrations should, 
 in the proper sense, account for our sensa- 
 tions. It would, indeed, be ridiculous in 
 any man to pretend that thought of any kind 
 must necessarily result from motion, or 
 that vibrations in the nerves must neces- 
 sarily produce thought, any nuirc than the 
 vibrations of a pendulum. l)r Hartley 
 disclaims this way of thinking, and tliere- 
 fore it ought not to be imputed to him. 
 All that he pretends is, tliat, in the huiiian 
 constitution, there is a certain connection 
 l)Cl\veen vilirati'Mis in the medullary sub-
 
 252 
 
 ON THE INTELLECTUAL POWERS. 
 
 [^ESSAY II. 
 
 stance of the nerves and brain, and tho 
 thoughts of the mind ; so that the last de- 
 pend entirely upon the first, and every kind 
 of thought [91] in the mind arises in conse- 
 quence of a corresponding vibration, or 
 vibratiuncle in the nerves and brain. Our 
 sensations arise from vibrations, and our 
 ideas from vibratiuncles, or miniature vibra- 
 tions ; and he comprehends, under these 
 two words of sensations and ideas, all the 
 operations of the mind. 
 
 But how can we expect any proof of the 
 connection between vibrations and thought, 
 when the existence of such vibrations was 
 never proved ? Tlie proof of their connec- 
 tion cannot be stronger than the proof of 
 their existence ; for, as the author acknow- 
 ledges that we cannot infer the existence 
 of the thoughts from the existence of the 
 vibrations, it is no less evident that we can- 
 not infer the existence of vibrations from 
 the existence of our thoughts. The exist- 
 ence of both must be known before we can 
 know their connection. As to the exist- 
 ence of our thoughts, we have the evidence 
 of consciousness, a kind of evidence that 
 never was called in question. But as to 
 the existence of vibrations in the medullary 
 substance of the nerves and brain, no proof 
 has yet been brought. 
 
 All, therefore, we have to expect from 
 this hypothesis, is, that in vibrations, con- 
 sidered abstractly, there should be a variety 
 in kind and degree, which tallies so exactly 
 with the varieties of the thoughts they are to 
 account for, as may lead us to suspect some 
 connection between the one and the other. 
 If the divisions and subdivisions of thought 
 be found to run parallel with the divisions 
 and subdivisions of vibrations, this would 
 give that kind of plausibility to the hj-po- 
 thesis of their connection, which we com- 
 monly expect even in a mere hypothesis ; 
 but we do not find even this. 
 
 For, to omit all those thoughts and oper- 
 ations which the author comprehends under 
 the name of ideas, and which he thinks are 
 connected with vibratiuncles ; to omit the 
 perception of external objects, which he 
 comprehends under the name oi sensations ; 
 to omit the sensations, properly so called, 
 which accompany our passions [92] and 
 affections, and to confine ourselves to the 
 sensations which we have by means of our 
 external senses, we can perceive no corre- 
 spondence between the variety we find in 
 their kinds and degrees, and that wliich may 
 be supposed in vibrations. 
 
 We have five senses, whose sensations 
 differ totally in kind. By each of these, 
 excepting perhaps that of hearing, we have 
 a variety of sensations, wliich differ specific- 
 ally, and not in degree only. How many 
 tastes and smells are there which are spe- 
 fically different, each of them capable of all 
 
 degrees of strength and weakness ? Heat 
 and cold, roughness and smoothness, hard- 
 ness and softness, pain and pleasure, are 
 sensations of touch that differ in kind, and 
 each has an endless variety of degrees. 
 Sounds have the qualities of acute and 
 grave, loud and low, with all different de- 
 grees of each. The varieties of colour are 
 many more than we have names to express. 
 How shall we find varieties in vibrations 
 corresponding to all this variety of sensa- 
 tions which we have by our five senses 
 only ? 
 
 I know two qualities of vibrations in an 
 uniform elastic medium, and I know no 
 more. They may be quick or slow in vari- 
 ous degrees, and they may be strong or 
 weak in various degrees ; but I cannot find 
 any division of our sensations that will make 
 them tally with those divisions of vibra- 
 tions. If we had no other sensations but 
 those of hearing, the theory would answer 
 well ; for sounds are either acute or grave, 
 which may answer to quick or slow vibra- 
 tions ; or they are loud or low, which an- 
 swer to strong or weak vibrations. But 
 then we have no variety of vibrations cor- 
 responding to the immense variety of sens- 
 ations which we have by sight, smell, taste, 
 and touch. 
 
 Dr Hartley has endeavoured to find out 
 other two qualities of vibrations ; to wit, 
 that they may primarily affect one part of 
 the brain or another, and that they may 
 vary in their direction according as they 
 enterby different external nerves ; but these 
 [93] seem to be added to make a number; 
 for, as far as we know, vibrations in an 
 uniform elastic substance spread over the 
 whole, and in all directions. However, 
 tliat we may be liberal, we shall grant him 
 four different kinds of vibrations, each of 
 them having as many degrees as he pleases. 
 Can he, or any man, reduce all our sensa- 
 tions to four kinds ? W« have five senses, 
 and by each of them a variety of sensations, 
 more than sufficient to exhaust all the 
 varieties we are able to conceive in vibra- 
 tions. 
 
 Dr Hartley, indeed, was sensible of the 
 difficulty of finding vibrations to suit all the 
 variety of our sensations. His extensive 
 knowledge of physiology and pathology 
 could yield him but a feeble aid ; and, there- 
 fore, he is often reduced to the necessity of 
 heaping supposition upon supposition, con- 
 jecture upon conjecture, to give some credi- 
 bility to his hypothesis ; and, in seeking out 
 vibrations which may correspond with the 
 sensations of one sense, he seems to forget 
 that those must be omitted which have been 
 appropriated to another. 
 
 Philosophers have accounted in some de- 
 gree for our various sensations of sound by 
 the vibrations of elastic air; but it is to be 
 
 [91-93
 
 CHAP. IV.3 
 
 FALSE CONCLUSIONS, &c. 
 
 253 
 
 observed, first. That we know that such vi- 
 brations do really exist ; and, secondly, That 
 they tally exactly with the most remarkable 
 phsenomena of sound. We cannot, indeed, 
 shew how any vibration should produce the 
 sensation of sound. This must be resolved 
 into the will of God, or into some cause 
 altogether unknown. But we know that, 
 as the vibration is strong or weak, the 
 sound is loud or low ; we know that, as the 
 vibration is quick or slow, the sound is 
 acute or grave. We can point out that 
 relation of synchronous vibrations which 
 produces harmony or discord, and that 
 relation of successive vibrations which pro- 
 duces melody ; and all this is not conjec- 
 tured, but proved by a sufficient induction. 
 This account of sounds, therefore, is philo- 
 sophical : although, perhaps, there may be 
 many things relating to sound that we can- 
 not account for, and of which the causes 
 remain latent. The connections described 
 [94] in this branch of philosophy are the 
 work of God, and not the fancy of men. 
 
 If anything similar to this could be shewn 
 in accounting for all our sensations by 
 vibrations in the medullary substance of the 
 nerves and brain, it would deserve a place 
 m sound philosophy ; but, when we are told 
 of vibrations in a substance which no man 
 could ever prove to have vibrations, or to 
 be capable of them ; when such imaginary 
 vibrations are brought to account for all our 
 sensations, though we can perceive no cor- 
 respondence in their variety of kind and 
 degree to the variety of sensations — the con- 
 nections described in such a system are the 
 creatures of human imagination, not the 
 work of God. 
 
 The rays of light make an impression 
 upon the optic nerves ; but they make none 
 upon the auditory or olfactory. The vibra- 
 tions of the air make an iuiprcssiou upon 
 the auditory nerves ; but none upon the 
 optic or the olfactory. The effluvia of 
 bodies make an impression upon the olfac- 
 tory nerves ; but make none upon the optic 
 or auditory. No man has been able to give 
 a shadow of reason for this. While this is 
 the ca.se, is it not better to confess our 
 ignorance of the nature of those impressions 
 made upon tl:e nerves and brain in percep- 
 tion, than to Hatter our pride with the con- 
 ceit of knowledge whicli we have not, and 
 to adulterate philosophy with the spurious 
 brood of hypotheses ?• 
 
 • Kcid appears to liave been iinacquainteil with 
 the wort s anil tlicory of Bonnet. — With our author's 
 atrictures on the physiolnpical liy()othcsc8, the reader 
 may com j .are those of 'letens, in hin " Vet«uche." 
 and of Siewart in his" Philosophical Kasaya." — H. 
 
 [04, 95-J 
 
 CHAPTER IV. 
 
 F.\LSE CONCLUSIONS DRAWN FROM THH 
 IMPRESSIONS BEFORE MENTIONED. 
 
 Some pliilosophers among the ancients, 
 as well as among the moderns, imagined 
 that man is nothing but a piece of matter, 
 so curiously organized that the impressions 
 of external objects produce in it sensation, 
 perception, remembrance, and all the other 
 operations [95] we are conscious of.* This 
 foolish opinion could only take its rise from 
 observing the constant connection which 
 the Author of Nature hath established be- 
 tween certain impressions made upon our 
 senses and our perception of the objects by 
 which the imiiression is made ; from which 
 they weakly inferred that those impressions 
 were the proper efficient causes of the cor- 
 responding perception. 
 
 Hut no reasoning is m^re fallacious than 
 this — that, because two things are always 
 conjoined, therefore one must be the cause 
 of the other. Day and night have been 
 joined in a constant succession since the 
 beginning of the world; but who is so foolish 
 as to conclude from this that day is the 
 cause of night, or night the cause of the 
 following day ? There is indeed nothing 
 more ridiculous than to imagine that anv 
 motion or modification of matter should pro- 
 duce thought. 
 
 If one should tell of a telescope so exactly 
 made as to have the power of seeing ; of a 
 whispering gallery that had the power of 
 hearing ; of a cabinet so nicely framed as to 
 have the power of memory ; or of a machine 
 so delicate as to feel pain when it was 
 touched — such absurdities are so shocking to 
 common sense that they would not find belief 
 even among savages ; yet it is the same 
 absurdity to think that the iui]>rossions of 
 external objects upon the machine of our 
 bodies can be the real efficient cause of 
 thought and perception. 
 
 Passing this, ther(!tore, as a notion too 
 absurd to admit of reasoning, another con- 
 clusion very generally made by philoso- 
 phers is, that, in i)ercei)tion, an impression 
 is made upon the mind as woll as u]ion the 
 organ, nerves, and brain. Aristotle, as 
 was before observed, thought that the form 
 or image of the object perceived, enters by 
 
 * 'i'lip stoics are icprthended for such n duclrino 
 hy liocthius: — 
 
 •' Quondam porticua attulit 
 
 Obscuros nmuuHi fients, 
 
 Qui sensus ct imagines 
 
 K corporihUH extunis 
 
 C'reiiant meniihus impriini, 
 
 Ut qui nclani eileri stylo 
 
 Mos fst aquorc p»;,'inir 
 
 Quae Miillas iMljeat iii>ta<, 
 
 I'iciisas (igiTe liliraa." Iftc 
 'f\\c tiiliula rasa reniounta, howevir, to Ari«lollt 
 — intleed to I'lalo— as an illu>liation — II.
 
 254 
 
 ON THE INTELLECTUAL POWERS. 
 
 [kSSaY II. 
 
 the organ of sense, and strikes upon the 
 mind." Mr IJume gives the name of im- 
 pressions to all our perceptions, to all our 
 sensations, and even to the objects which 
 we perceive. Mr Locke affirms very posi- 
 tively, that the ideas of external objects are 
 produced [96] in our minds by impulse, 
 " that being the only way we can conceive 
 bodies to operate in." It ought, however, to 
 be observed, in justice to Mr Locke, that he 
 retracted this notion in his first letter to the 
 Bishop of Worcester, and promised, in the 
 next edition of his Essay, to have that pas- 
 sage rectified ; but, either from forgetlul- 
 ness in the author, or negligence in the 
 printer, the passage remains in all the sub- 
 sequent editions 1 have seen. 
 
 There is no prejudice more natural to 
 man than to conceive of the mind as hav- 
 ing some similitude to body in its opera- 
 tions. Hence men have been prone to 
 imagine that, as bodies are put ui motion 
 by some impulse or impression made upon 
 them by contiguous bodies, so the mind is 
 made to think and to perceive by some im- 
 pression made upon it, or some impulse 
 given to it by contiguous objects. If we 
 have such a notion of the mind as Homer 
 had of his gods — who might be bruised or 
 wounded with swords and spears — we may 
 then understand what is meant by impres- 
 sions made upon it by a body ; but, if we 
 conceive the mind to be immaterial— of 
 which I think we have very strong proofs — 
 we shall find it difficult to affix a meaning 
 to impressions made upon it. 
 
 There is a figurative meaning of impres- 
 sions on the mind which is well authorized, 
 and of which we took notice in the observa- 
 tions made on that word ; but this meaning 
 applies only to objects that are interesting. 
 To say that an object which I see with per- 
 fect indifference makes an impression upon 
 my mind, is not, as I apprehend, good 
 Etiglish. If philosophers mean no more 
 but that I see the object, why should they 
 invent an improper phrase to express what 
 every man knows how to express in plain 
 English ? 
 
 But it is evident, from the maimer in 
 which this phrase is used by modern philo- 
 sophers, that they mean, not barely to ex- 
 press by it ray perceiving an object, but to 
 explain the manner of perception. They 
 think that the object perceived acts upon 
 the mind in some way similar to that in 
 which one body acts upon another, by 
 making [97] an impression upon it. The 
 impression upon the mind is conceived to 
 be something wherein the mind is alto- 
 gether passive, and has some effect pro- 
 
 • A mere metaphor in Aristotle. (See Notes K 
 and M.) At any rate, the impnssion was supposed 
 to be made on the animated eensorj, am; nut on the 
 intellect.— H. 
 
 duced in it by the object. But this is a 
 hypothesis which contradicts the common 
 sense of mankind, and which ought not to 
 be admitted without proof. 
 
 When I look upon the wall of my room, 
 the wall does not act at all, nor is capable 
 of acting ; the perceiving it is an act or 
 operation in me. That this is the common 
 apprehension of mankind with regard to 
 perception, is evident from the manner of 
 expressing it in all languages. 
 
 The vulgar give themselves no trouble 
 how they perceive objects — they express 
 what they are conscious of, and they express 
 it with propriety ; but philosophers have an 
 avidity to know how we perceive objects; 
 and, conceiving some similitude between a 
 body that is put in motion, and a mind that 
 is made to perceive, they are led to think 
 that, as the body must receive some impulse 
 to make it move, so the mind must receive 
 some impulse or impression to make it per- 
 ceive. This analogy seems to be confirmed, 
 by observing that we perceive objects only 
 when they make some impression upon the 
 organs of sense, and upon the nerves and 
 brain ; but it ought to be observed, that 
 such is the nature of body that it cannot 
 change its state, but by some force impressed 
 upon it. This is not the nature of mind. 
 All that we know about it shews it to be in 
 its nature living and active, and to have 
 the power of perception in its constitution, 
 but still within those limits to which it is 
 confined by the laws of Nature. 
 
 It appears, therefore, that this phrase of 
 the mind's having impressions made upon 
 it by corporeal objects in perception, ia 
 either a phrase without any distuict mean- 
 ing, and contrary to the propriety of the 
 English language, or it is grounded upon 
 an hypothesis which is destitute of proof. 
 On that account, though we grant that in 
 perception there is an impression made 
 upon the organ of [98] sense, and upon the 
 nerves and brain, we do not adn)it that 
 the object makes any impression upon the 
 mind. 
 
 There is another conclusion drawn from 
 the impressions made upon the brain in 
 perception, which 1 conceive to have no 
 solid foundation, though it has been adopted 
 very generally by philosophers. It is, that, 
 by the impressions made on the brain, 
 images are formed of the object ])erceived ; 
 and that the mind, being seated in the brain 
 as its chamber of presence, immediately 
 perceives those images only, and has no 
 perception of the external object but by 
 them. This notion of our perceiving ex- 
 ternal olijects, not immediately, but in cer- 
 tain images or species of them conveyed by 
 the senses, seems to be the most ancient 
 philosophical hypothesis we have on the 
 subject of perception, and to have with 
 
 1^96-98]
 
 CHAP. 
 
 IV.] 
 
 FALSE CONCLUSIONS, &c. 
 
 255 
 
 small variations retained its authority to 
 this day. 
 
 Aristotle, as was before observed, main- 
 tained, that the species, images, or forms 
 of external objects, coming from the object, 
 are impressed on the mind. The followers 
 of Democritus and Epicurns held the same 
 thing, with regard to slender films of sub- 
 tile matter coming from the object, tliat 
 Aristotle did with regard to his immaterial 
 species or forms. 
 
 Aristotle thought every object of human 
 understanding enters at first by the senses ;* 
 and that the notions got by them are by 
 the powers of the mind refined and spirit- 
 ualized, so as at last to become objects of 
 the most sublime and abstracted science?. 
 Plato, on the other hand, had a very mean 
 opinion of all the knowledge we get by the 
 senses. He thought it did not deserve tlie 
 name of knowledge, and could not be the 
 foundation of science ; because the objects 
 of sense are individuals only, and are in a 
 constant fluctuation. AH science, according 
 to him, must be employed about those 
 eternal and immutable ideas which existed 
 before the objects of sense, and are not liable 
 to any change. In this there was an essen- 
 tial difference between the systems of these 
 two philosophers. [99] The notion of eter- 
 nal and immutable ideas, which Plato bor- 
 rowed from the Pytliagorean school, was 
 totally rejected by Aristotle, who held it as 
 a maxim, that there is nothing in the intel- 
 lect, which was not at first in the senses. 
 
 But, notwithstanding this great difference 
 in those two ancient systems, they might 
 both agree as to 'the manner in which we 
 perceive objects by our senses : and that 
 they did so, I think, is probable ; because 
 Aristotle, as far as I know, neither takes 
 notice of any difference between himself 
 and his master upon this point, nor lays 
 claim to his theory of the manner of our 
 perceiving objects as his own invention. 
 It is still more probable, from the hints 
 which Plato gives in the seventh book of his 
 Republic, concerning the manner in w-hich 
 we perceive the objects of sense ; which he 
 compares to persons in a deep and dark cave, 
 who see not externnl objects themselves but 
 only their shadows, by a light let into the 
 cave through a small opening. -f 
 
 It seems, therefore, probable that tlic Py- 
 thagoreans and Platonists agreed with the 
 Peripatetics in this general theory of per- 
 ception — to wit, that tile oljjects of sense 
 
 * This is a very rtnubtful point, and has accord. 
 inRly divided his followers. Texts can be quoted to 
 prove, on the one side, that ArislotI ■ i'cri»ed all our 
 notions, a posteriori, from the experience of s<nse; 
 and, on the other, that he viewed sense only an aflbrd 
 JiiR to intellect the c ndition retjuibite lor it lobe, 
 come aclually cmpcious of the native and neces-ary 
 notions it, ti pmiri, virtually possesfcul. — II. 
 
 + Heid wholly mistakes the meaninii of Plato's 
 •imilc of the cave. See below, under p 1 10. — H. 
 
 [99, 100] 
 
 are perceived only by certain images, or 
 shadows of them, let into the mind, as into 
 a camrra o/iscuru.* 
 
 The notions of the ancients were very 
 various wit!) regard to the seat of the soul 
 Since it has been discovered, by the im- 
 provements in anatomy, that the nerves 
 are the instruments of perception, and of 
 the sensations accompanying it, and that 
 the nerves ultimately terminate in the 
 brain,-}- it has been the general opinion of 
 philosophers that the brain is the seat of 
 the soul ; and that slie perceives the images 
 that are brought there, and external thmgs, 
 only by means of them. 
 
 Des Cartes, observing that the pineal 
 gland is the only part of the brain that is 
 single, all the other parts being double,^ 
 and tliinking tliat the soul mu.st liave one 
 seat, was determined by this [100] to make 
 that gland the soul's habitation, to which, 
 by means of the animal spirits, inteUigence 
 is brought of all objects that affect the 
 senses. § 
 
 Others have not thought proper to con- 
 fine the habitation of the soul to the pineal 
 gland, but to the brain in general, or to 
 some part of it, which they call the seii- 
 soriiim. Even the great Newton favoured 
 this opinion, though he proposes it only as 
 a query, with that modesty which dis- 
 tinguished him no less than his great genius. 
 "Is not," says he, " the sensorium of animals 
 the place where the sentient substance is 
 present, and to which the sensible species of 
 things are brought through the nerves and 
 brain, that there they may be perceived by 
 the mind present in that j)lace ? And is 
 there not an incorporeal, living, intelligent, 
 and omnipresent Being, who, in infinite 
 space, as if it were in his sensorium, inti- 
 mately perceives thinus themselves, and 
 comprehends them perfectly, as being frv- 
 .sent to them ; of wliich things, tliat prin- 
 ciple in us, which perceives and thinks, 
 discerns only, in its little sensorium, the 
 images brought to it through the organs of 
 the senses ?"|1 
 
 His great friend Dr Samuel Clarke 
 adopted the same sentiment with morecon- 
 fidince. In his papers to Leibnitz, we 
 find the following passages: "Without 
 Ijeing present to the images of the things 
 perceived, it (the soul) could not possibly 
 perceive them. A living substance can 
 only there j)crceive where it is present, 
 either to the things themselves, (as the 
 omnipresent God is to the whole universe.) 
 
 • Anerror. Sec below, underp. 116. — H, 
 
 + That if, since the time of Krasistratiisand Galen. 
 — H. 
 
 t Which is not the case. The Myixil'hysii, the 
 Vermiform process, &c., . re not le».s single than the 
 Conariiim — H. 
 
 k See .ihove, p. 2it, h, note * — U. 
 
 II Belorc Heid, these crude conjeetnrcii of Newton 
 were justly censured liy (»enove»i, and oilier — 11.
 
 256 
 
 ON THE INTELLECTUAL TOWERS. 
 
 [essay II. 
 
 or to the images of things, (as the soul of 
 man is in its proper sensory.) Nothing 
 can any more act, or be acted upon, where 
 it is not present, than it can be where it is 
 not. We are sure the soul cannot perceive 
 what it is not present to, because nothing 
 can act, or be acted upon, where it is not." 
 
 Mr Locke expresses himself so upon 
 this point, that, for the [101] most part, 
 one would imagine that he thought that 
 the ideas, or images of things, which he be- 
 lieved to be the immediate objects of per- 
 ception, are impressions upon the mind it- 
 self; yet, in some passages, he rather 
 places them in the brain, and makes them 
 to be perceived by the mind there present. 
 " There are some ideas," says he, " which 
 have admittance only through one sense ; 
 and, if the organs or the nerves, which are 
 the conduits to convey them from without 
 to their audience in the brain, the mind's 
 presence room, if I may so call it, are so 
 disordered as not to perform their function, 
 they have no postern to be admitted by. 
 
 " There seems to be a constant decay of 
 all our ideas, even of those that are struck 
 deepest. The pictures drawn in our minds 
 are laid in fading colours. Whether the 
 temper of the brain makes this difference, 
 that in some it retains the characters drawn 
 on it like marble, in others like freestone, 
 and in others little better than sand, I shall 
 not enquire."* 
 
 From these passages of Mr Locke, and 
 others of a like nature, it is plain that he 
 thought that there are images of external 
 objects conveyed to the brain. But whether 
 he thought with Des Cartes-)- and Newton, 
 that the images in the brain are perceived 
 by the mind there present, or that they are 
 imprinted on the mind itself, is not so evi- 
 dent. 
 
 Now, with regard to this hypothesis, 
 there are three things that deserve to be 
 considered, because the hypothesis leans 
 upon them ; and, if any one of them fail, it 
 must fall to the ground. The Jirst is, That 
 the soul has its seat, or, as Mr Locke calls 
 it, its presence room in the brain. The 
 second, That there are images formed in 
 the brain of all the objects of sense. The 
 third, That the mind or soul perceives these 
 images in the brain ; and that it perceives 
 not external objects immediately, but only 
 perceives them by means of those images. 
 L102] 
 
 As to the^/-5/ point — that the soul has its 
 
 » No great stress should be laid on such figurative 
 passages as indications ot the real opinion of I^ocke, 
 which, on this point, it is not easy to discover. See 
 NnteO H. 
 
 t Des Cartes is perhaps an erratum for Dr Clarke. 
 If not, the opinion of Des Cartes is misrepresented ; 
 fnr he denied to the mind all consciousness or imme- 
 diate knowledge of matter and its modifications. 
 But of this again. See Note N H. 
 
 seat in the brain — this, surely, is not so well 
 established as that we can safely build 
 other principles upon it. There have been 
 various opinions and much disputation about 
 the place of spirits : whether they have a 
 place ? and, if they have, how they occupy 
 that place ? After men had fought in the 
 dark about those points for ages, the wiser 
 part seem to have left off disputmg about 
 them, as matters beyond the reach of the 
 human faculties. 
 
 As to the second point — that images of all 
 the objects of sense are formed in the brain — 
 we may venture to affirm that there is no 
 proof nor probability of this, with regard to 
 any of the objects of sense ; and that, with 
 regard to the greater part of them, it is 
 words without any meaning.* 
 
 We have not the least evidence that the 
 image of any external object is formed in 
 the brain. The brain has been dissected 
 times innumerable by the nicest ana- 
 tomists ; every part of it examined by the 
 naked eye, and with the help of microscopes ; 
 but no vestige of an image of any external 
 object was ever found. The brain seems 
 to be the most improper substance that can 
 be imagined for receiving or retaining; images, 
 bemg a soft, moist, medullary substance. 
 
 But how are these images formed ? or 
 whence do they come ? Says Mr Locke, the 
 organs of sense and nerves convey them from 
 without. This is just the Aristotelian 
 hypothesis of sensible species, whicli modern 
 philosophers have been at great pains to 
 refute, and which must be acknowledged to 
 be one of the most unintelligible parts of 
 the Peripatetic system. Those who con- 
 sider species of colour, figure, sound, and 
 smell, coming from the object, and entering 
 by the organs of sense, as a part of the 
 scholastic jargon long ago discarded from 
 sound philosophy, ought to have discarded 
 images in the brain along with them. 
 There never was a shadow of argument 
 brought by any author, to shew that an 
 [103] image of any external object ever 
 entered by any of the organs of sense. 
 
 That external objects make some impres- 
 sion on the organs of sense, and by them on 
 the nerves and brain, is granted ; but that 
 those impressions resemble the objects 
 they are made by, so as that they may be 
 called images of the objects, is most impro- 
 bable. Every hypothesis that has been 
 contrived, shews that there can be no such 
 resemblance ; for neither the motions of 
 animal spirits, nor the vibrations of elastic 
 chords, or of elastic tether, orof theinfinites- 
 
 « It would lie rash to assume that, because a phi. 
 losopher uses the term image, or impression, or idea, 
 and places what it denotes in the brain, that he 
 therefore means that the mind was cognizant of such 
 corporeal affection, as of its object, either in percep. 
 tion or imagination, hec .^ote K. — H. 
 
 [101-103]
 
 CHAP. IV.] 
 
 FALSE CONCLUSIONS, &c. 
 
 257 
 
 imal particles of the nerves, can be sup- 
 posed to resemble the objects by which 
 they are excited. 
 
 We know that, in vision, an image of the 
 visible object is formed in the bottom of the 
 eye by the rays of light. But we know, 
 also, that this image cannot be conveyed to 
 the brain, because the optic nerve, and all 
 the parts that surround it, are opaque and 
 impervious to the rays of light ; and there 
 is no other organ of sense in which any 
 image of the object is formed. 
 
 It is farther to be observed, that, with 
 regard to some objects of sense, we may 
 understand what is meant by an image of 
 them imprinted on the brain ; but, with 
 regard to most objects of sense, the phrase 
 is absolutely unintelligible, and conveys no 
 meaning at all. As to objects of sight, I 
 understand what is meant by an image of 
 their figure in the brain. But how shall we 
 conceive an image of their colour where there 
 is absolute darkness ? And as to all other 
 objects of sense, except figure and colour, 
 I am unable to conceive what is meant by an 
 image of them. Let any man say what he 
 means by an image of heat and cold, an image 
 of hardness or softness, an image of sound, 
 or smell, or taste. The word image, when 
 applied to these objects of sense, has abso- 
 lutely no meaning. Upon what a weak 
 foundation, then, does this hypothesis stand, 
 when it supposes that images of all the 
 objects of sense are imprinted on the brain, 
 being conveyed thither Ijy the conduits of the 
 organs and nerves !* [104] 
 
 The third point in this hypothesis is, 
 That the mind perceives the images in the 
 brain, and external objects only by means 
 of them. This is as improbable as that 
 there are such images to be perceived. If 
 our powers of perception be not altogether 
 fallacious, the objects we perceive are not 
 in our brain, but without us.-f We are so 
 far from perceiving images in the brain, 
 that we do not perceive our brain at all ; 
 nor would any man ever have known that 
 he had a brain, if anatomy had not dis- 
 covered, by dissection, that the brain is a 
 constituent part of the human body. 
 
 To sum up what has been said with re- 
 gard to the organs of perception, and the 
 impressions made upon our nerves and 
 brain. It is a law of our nature, estab- 
 lished by the will of the Supreme Being, 
 that we perceive no external object but by 
 
 t These olijections to the hypolheais in quc-stini), 
 have been frequently urged buth in ancient and in 
 modern time*. See Note K. — H. 
 
 t If this I'C taken litcr.illy and by ilself, then, ac 
 cording to Reid, perception \-> not an immanent 'or- 
 niti"!! ; extLiii-ion and fu'ure are, in tli.it ait, \\»\ 
 merely ►ug(;''''t' d coiiceptiuiiH ; and, an we are perci. 
 pientol the iirin-i'go, and,cori8ii()Ui<ij|ihei'crception, 
 we are therefore conscious of the nun. ego. but see 
 NoteC— H. 
 
 [lot, 10.5] 
 
 means of the organs given us for that pur- 
 pose. But these organs do not perceive. 
 The eye is the organ of sight, but it sees 
 not. A telescope is an artificial organ of 
 sight. The eye is a natural origan of sight, 
 but it sees as little as the telescope. * We 
 know how the eye forms a picture of the 
 visible object upon the retina ; but how this 
 picture makes us see the object we know 
 not ; and if experience had not informed us 
 that such a picture is necessary to vision, 
 we should never have known it. We can 
 give no reason why the jiicture on the re- 
 tina should be followed by vision, while a 
 like picture on any other part of the body 
 produces nothing like vision. . 
 
 It is likewise a law of our nature, that we 
 perceive not external objects, unless certain 
 impressions be made by the object upon the 
 organ, and by means of the organ upon the 
 nerves and brain. But of the nature of 
 those impressions we are perfectly ignorant ; 
 and though they are conjoined with percep- 
 tion by the will of our JNIaker, yet it does 
 not appear that they have any necessary con- 
 nection with it iu their own nature, far less 
 that they can be the proper efficient cause 
 of it. [ 105] We perceive, because God lirs 
 given us the power of perceiving, and not 
 because we have impressions from objects. 
 We perceive nothing without those impres- 
 sions, because our Maker has limited and 
 circumscribed our powers of perception, by 
 such laws of Nature as to his wisdom seemed 
 meet, and such as suited our rank in his 
 creation.* 
 
 * The doctrine of Reid and Stewart, in regard to 
 our perception of external things, bears a close ana- 
 logy to the Cartesian scheme of divine a^sts'ancc, or 
 ot occasional causes It seems, however, to coinc <ie 
 most completely with the opinion of Kuardus Andala, 
 a Dutch Cartesian, who .(ttemplcd to reconcile the 
 theory of assistance with that oi physical ivfltience. 
 ".Statuo," he says, "nosclarissimaniet distinct issimam 
 hujns upcratiimis e! nnioriis posse habere identn, si 
 modo, quod omnino factre oportet, ad Ileum, caiis- 
 sam ejus primam it liberam a.-condamus, et abejus 
 beneplacito admiraiuium huiic ettcctuni derivimus. 
 Nos posfumus hiiic vel illi motui e. gr. campana?, 
 SIC tt hcdera? suspense. Uteris scriptis, verbis ciuilnis- 
 cunque ptonunciatis, aliisqoe signis, vaiias ideas 
 alligare, ita, ut per visum, vel auilituni in meiite ex. 
 citentur varia; idea;, p^rceptiones it fcnsationis.- 
 annon hincclare et facile inli'llijinius, Deuni cre.-i- 
 lorem m ntis et corporis poliiisfC in>tituereet on i. 
 I are, ut per va.ios in corpoie motus varia; in n-ente 
 cxcitenlur idea; et perceptioncs ; et vicissini, ut per 
 varia< mentis volitione^, varii in corpore ixcilentur 
 et producantur im tus ? H nc et pro varia alt( r. 
 utrius partis di-positione alli'ra iiars variis moifis 
 affici pote.-t. Hoc autem a Deo ita ordinatumet 
 eHectum esfe, a posteriori, conlinua, cerlissim.i et 
 clarissima experientia docet Testes irrelr.igaliiles 
 omnique (xccptinne majirtg reciproci hujiis ccm. 
 imrcii, operalioiiis mentis in corpus, et cori oris in 
 meiitein, nee non cmiimunionis .status, sunt lensus 
 omnes turn exlerni, tuin iulerni \ ut et oinnes ct 
 singula; et conlinua; actiones mentis in corp «, dc 
 quibus iiioilo fiiit actum. M quis vcro a pnpriela- 
 ////u» mentis ad /)/«/)rii7(j/r» corporis prugniii velit, 
 aut I xnrt/«>rt<liviii.i8>ii«iariiin hariiiii .■.nlis'antiariim 
 dc.luitreinotum m corpoce, ti percept iniies in ii onle, 
 aut lios ell'ectus ut necessario lomiexoK spictaie ; 
 na' is frustraerit, nihil intelligct, perveisissime i hi.
 
 258 
 
 ON THE INTELLECTUAL POWERS. 
 
 LESSAy II. 
 
 CHAPTER V. 
 
 OF PERCEPTION. 
 
 In speaking of the impressions made on 
 our organs in perception, we build upon 
 facts borrowed from anatomy and physio- 
 logy, for which we have the testimony of 
 our senses. But, being now to speak of 
 perception itself, which is solely an act of 
 the mind, we must appeal to another 
 authority. The operations of our minds 
 are known, not by sense, but by conscious- 
 ness, the authority of which is as certain 
 and as irresistible as that of sense. 
 
 In order, however, to our having a distinct 
 notion of any of the operations of our own 
 minds, it is not enough that we be conscious 
 of them ; for all men have this consciousness. 
 It is farther necessary that we attend to them 
 while they are exerted, and reflect upon them 
 with care, while they are recent and fresh 
 in our memory. It is necessary that, by 
 employing ourselves frequently in this way, 
 we get the habit of this attention and reflec- 
 tion ; and, therefore, for the proof of facts 
 which I shall have occasion to mention upon 
 this subject, I can only appeal to the reader's 
 own thoughts, whether such facts are not 
 agreeable to what he is conscious of in his 
 own mind. [106] 
 
 If, therefore, we attend to that act of 
 our mind which we call the perception of an 
 external object of sense, we shall find in it 
 these three things : — First, Some con- 
 ception or notion of the object perceived ; 
 Secondly/, A strong and irresistible convic- 
 tion and belief of its present existence ; and. 
 Thirdly, That this conviction and belief are 
 immediate, and not the effect of reasoning. " 
 
 First, It is impossible to perceive an 
 object without having some notion or con- 
 ception of that which we perceive. We 
 may, indeed, conceive an object which we 
 do not perceive ; but, wlien we perceive the 
 object, we must have some conception of it 
 at the same time ; and we have commonly 
 a more clear and steady notion of the object 
 while we perceive it, than we have from 
 memory or imagination when it is not per- 
 ceived. Yet, even in perception, the notion 
 which our senses give of the object may be 
 more or less clear, more or less distinct, in 
 all possible degrees. 
 
 Thus we see more distinctly an object at 
 a small than at a great distance. An object 
 at a great distance is seen more distinctly in 
 
 losophabitur nullamque hujus rei ideam habere po. 
 terit. Si vero ad Deum t reatorem adscendamus, 
 eumque vere agnoscamus, nihil hie erit obscuri, 
 hunc effectum clari.'simeintelligemus, et quidem per 
 eaujsam ejus primam ; quas perfectissima demum 
 est scientia." — H. 
 
 * See above, p. 183, a, note • : p. 128, b, note « ; 
 and Note C H. 
 
 a clear than in a foggy day. An object 
 seen indistinctly with the naked eye, on 
 account of its smallness, may be seen dis- 
 tinctly with a microscope. The objects in 
 this room will be seen by a person in the 
 room less and less distinctly as the light of 
 the day fails ; they pass through all the 
 various degrees of distinctness according to 
 the degrees of the light, and, at last, in 
 total darkness they are not seen at all. 
 What has been said of the objects of sight 
 is so easily applied to the objects of the 
 other senses, that the application may bo 
 left to the reader. 
 
 In a matter so obvious to every person 
 capable of reflection, it is necessary only 
 farther to observe, that the notion which 
 we get of an object, merely by our external 
 sense, ought not to be confounded with that 
 more scientific notion which a man, come to 
 the years of understanding, may have of the 
 same object, by attending to its various 
 attributes, or to its various parts, and their 
 relation to each other, and to the whole. 
 [107] Thus, the notion which a child has of 
 a jack for roasting meat, will be acknowledged 
 to be very different from that of a man who 
 understands its construction, and perceives 
 the relation of the parts to one another, and 
 to the whole. The child sees the jack and 
 every part of it as well as the man. The 
 child, therefore, has all the notion of it 
 which sight gives ; whatever there is more 
 in the notion which the man forms of it, 
 must be derived from otlier powers of the 
 mind, which may afterwards be explained. 
 This observation is made here only that we 
 may not confound the operations of differ- 
 ent powers of the mind, which by being 
 always conjoined after we grow up to under- 
 standing, are apt to pass for one and the same. 
 
 Secondly, In perception we not only have 
 a notion more or less distinct of the object 
 perceived, but also an irresistible conviction 
 and belief of its existence. This is always 
 the case when we are certain that we per- 
 ceive it. There may be a perception so 
 faint and indistinct as to leave us in doubt 
 whether we perceive the object or not. 
 Thus, when a star begins to twinkle as the 
 light of the sun withdraws, one maj', for a 
 short time, think he sees it without being 
 certain, until the perception acquire some 
 strength and steadiness. When a ship just 
 begins to appear in the utmost verge of the 
 horizon, we may at first be dubious whether 
 we perceive it or not ; but when the percep- 
 tion is in any degree clear and steady, there 
 remains no doubt of its reality ; and when 
 the reality of the perception is ascertained, 
 the existence of the object perceived can no 
 longer be doubted.* 
 
 • In this paragraph there is a confusion of that 
 which is perceived and that which is inferred from 
 the perception.— H. 
 
 ri06, 1071
 
 CHAP, v.] 
 
 OF PERCEPTION. 
 
 259 
 
 By the laws of all nations, in the most 
 solemn judicial trials, wherein men's for- 
 tunes and lives are at stake, the sentence 
 passes according to the testimony of eye or 
 ear witnesses of good credit. An upright 
 judge will give a fair hearing to every objec- 
 tion that can be made to the integrity of a 
 witness, and allow it to be possible that he 
 may be corrupted ; but no judge will ever 
 suppose that witnesses maybe imposed upon 
 by trusting to their eyes and ears. And if 
 a sceptical counsel should plead against the 
 testimony of the witnesses, that they had 
 no other evidence for what they [108] de- 
 clared but the testimony of their eyes and 
 ears, and that we ought not to put so much 
 faith in our senses as to deprive men of life 
 or fortune upon their testimony, surely no 
 upright judge would admit a plea of this 
 kind. I believe no counsel, however scep- 
 tical, ever dared to offer such an argument ; 
 and, if it was offered, it would be rejected 
 with disdain. 
 
 Can any stronger proof be given that it 
 is the universal judgment of mankind that 
 the evidence of sense ijs a kind of evidence 
 which we may securely rest upon in the 
 most momentous concerns of mankind ; 
 that it is a kind of evidence against which 
 we ought not to admit any reasoning ; and, 
 therefore, that to reason either for or against 
 it is an insult to common sense ? 
 
 The whole conduct of mankind in the 
 daily occurrences of life, as well as the so- 
 lemn procedure of judicatories in the trial 
 of causes civil and criminal, demonstrates 
 this. I know only of two exceptions that 
 may be offered against this being the uni- 
 versal belief of mankind. 
 
 The first exception is that of some luna- 
 tics who have been persuaded of things that 
 seem to contradict the clear testimony of 
 their senses. It is said there have been 
 lunatics and hypochondriacal persons, who 
 seriously believed themselves to be made of 
 glass ; and, in consequence of this, lived in 
 continual terror of having their brittle frame 
 shivered into pieces. 
 
 All I have to say to this is, that our 
 minds, in our present state, are, as well as 
 our bodies, lialile to strange disorders ; and, 
 as we do not judge of the natural constitu- 
 tion of the Ijody from the disorders or dis- 
 eases to whicli it is subject from accidents, 
 80 neither ought we to judge of the natural 
 powers of the mind from its disorders, but 
 from its sound state. It is natural to man, 
 and conmion to the Kjiccies, to liave two 
 hands and two feet ; yet I have seen a man, 
 and a very ingenious one, wlio was born 
 without cither hands or feet. [lOI*) It is 
 natural to man to have faculties superior to 
 those of brutes ; yet wo see some indivi- 
 duals whose faculties are not equal to those 
 of many brutes ; and the wisest man may, 
 [108-110] 
 
 by various accidents, be reduced to this 
 state. General rules that regard those 
 whose intellects are sound are not over- 
 thrown by instances of men whose intellects 
 are hurt by any constitutional or accidental 
 disorder. 
 
 The other exception that may be made 
 to the principle we have laid down is that 
 of some philosophers who have maintained 
 that the testimony of sense is fallacious, 
 and therefore ought never to be trusted. 
 Perhaps it might be a sufficient answer to 
 this to say, that there is nothing so absurd 
 which some philosophers have not main- 
 tained.* It is one thing to profess a doc- 
 trine of this kind, another seriously to be- 
 lieve it, and to be governed by it in the 
 conduct of life. It is evident that a man 
 who did not believe his senses could not 
 keep out of harm's way an hour of his life ; 
 yet, in all the history of philosophy, we 
 never read of any sceptic that ever stepped 
 into fire or water because he did not believe 
 his senses, or that shewed in the conduct of 
 life less trust in his senses than other men 
 have.-f- This gives us just ground to appre- 
 hend that philosophy was never able to 
 conquer that natural belief which men have 
 m their senses ; and that all their subtile 
 reasonings against this belief were never 
 able to persuade themselves. 
 
 It appears, therefore, that the clear and 
 distinct testimony of our senses carrie? 
 irresistible conviction along with it to everj 
 man in his right judgment. 
 
 I observed. Thirdly, That this conviction 
 is not only irresistible, but it is immediate ; 
 that is, it is not by a train of reasoning 
 and argumentation that we come to be 
 convinced of the existence of what we 
 perceive ; we ask no argument for the 
 existence of the object, but that we per- 
 ceive it ; perception conmiands our belief 
 upon its own authority, and disdains to 
 rest its authority upon any reasoning what- 
 soever.:}: [110] 
 
 The conviction of a trutli may be irre- 
 sistible, and yet not immediate. Thus, my 
 conviction that the three angles of every 
 plain triangle are equal to two right angles, 
 is irresistible, but it is not innnediate ; I 
 am convinced of it by demonstrative rea- 
 soning. Thcro are other truths in mathe- 
 matics of wliich we have not only an irre- 
 sistible but an immediate conviction. Such 
 are the axioms. Our belief of tin; axioms 
 in mathematics is not grounded upon argii- 
 
 • A saying of Varro — H. 
 
 t All this we read, however, in Laijrtiiiii, of F'yrrhoj 
 and on the authority of Antigomn Carystlui, the 
 Ktcat sceptic's contemporary. Whether we arc to 
 believe the narrative is aimtlier qiiei<iioM. — H. 
 
 t If lliid holils that in perception we have only :< 
 conception of the A'o/i./Ao in the Ji^o, thi'* heliel ii 
 either not the reflex ol a ciiKniiion, liula hlin<l lailh, 
 or it is mediate, a» held by Stewart. — t'/ii o . /•-»». ii 
 c Vt. — II.
 
 260 
 
 ON THE INTELLECTUAL POWERS. 
 
 [essay II, 
 
 ment — arguments are grounded upon them ; 
 but their evidence is discerned immediately 
 by the human understanding. 
 
 It is, no doubt, one thing to have an 
 immediate conviction of a self-evident 
 axiom ; it is another thing to have an im- 
 mediate conviction of the existence of what 
 we see ; but the conviction is equally imme- 
 diate and equally irresistible in both cases. 
 No man thinks of seeking a reason to believe 
 what he sees ; and, before we are capable of 
 reasoning, we put no less confidence in our 
 senses than after. The rudest savage is as 
 fully convinced of what he sees, and hears, 
 and feels, as the most expert logician. The 
 constitution of our understanding deter- 
 mines us to hold the truth of a mathematical 
 axiom as a first principle, from which other 
 truths may be deduced, but it is deduced 
 from none ; and the constitution of our 
 power of perception determines us to hold 
 the existence of what we distinctly perceive 
 as a first principle, from which other truths 
 may be deduced ; but it is deduced from 
 none. What has been said of the irresis- 
 tible and immediate belief of the existence 
 of objects distinctly perceived, I mean only 
 to affirm with regard to persons so far ad- 
 vanced in understanding as to distinguish 
 objects of mere imagination from things 
 which have a real existence. Every man 
 knows that lie may have a notion of Don 
 Quixote, or of Garagantua, without any 
 belief that such persons ever existed ; and 
 that of Julius Caesar and Oliver Crom- 
 well, he has not only a notion, but a belief 
 that they did really exist. [Ill] But 
 whether children, from the time that they 
 begin to use their senses, make a distinction 
 between things which are only conceived or 
 imagined, and things which really exist, 
 may be doubted. Until we are able to 
 make this distinction, we cannot properly 
 be said to believe or to disbelieve the 
 existence of anything. The belief of the 
 existence of anything seems to suppose a 
 notion of existence — a notion too abstract, 
 perhaps, to enter into the mind of an in- 
 fant. I speak of the power of perception 
 in those that are adult and of a sound 
 mind, who believe that there are some 
 things which do really exist ; and that there 
 are many things conceived by themselves, 
 and by others, which have no existence. 
 That such persons do invariably ascribe 
 existence to everything which they distinctly 
 perceive, without seeking reasons or argu- 
 ments for doing so, is perfectly evident from 
 the whole tenor of human life. 
 
 The account I have given of our percep- 
 tion of external objects, is intended as a 
 faithful delineation of what every man, come 
 to years of understanding, and capable of 
 giving attention to what passes in his own 
 mind, may feel in himself. In what man- 
 
 ner the notion of external objects, and the 
 immediate belief of their existence, is pro- 
 duced by means of our senses, I am not 
 al)le to shew, and I do not pretend to shew. 
 If the power of perceiving external objects 
 in certain circumstances, be a part of the 
 original constitution of the human mind, 
 .all attempts to account for it will be vain. 
 No other account can be given of the con- 
 stitution of things, but the will of Him that 
 made them. As we can give no reason why 
 matter is extended and inert, why the mind 
 thinks and is conscious of its thoughts, but 
 the will of Him who made both ; so I sus- 
 pect we can give no other reason why, in 
 certain circumstances, we perceive ext'ernal 
 objects, and in others do not." 
 
 The Supreme Being intended that we 
 should have such knowledge of the material 
 objects that surround us, as is necessary in 
 order to our supplying the wants of nature, 
 and avoiding the dangers to which we are 
 constantly exposed ; and he has admirably 
 fitted our powers of perception to this 
 purpose. [112] If the intelligence we have 
 of external objects were to be got by 
 reasoning only, the greatest part of men 
 would be destitute of it ; for the greatest 
 part of men hardly ever learn to reason ; 
 and in infancy and childhood no man can 
 reason : Therefore, as this intelligence of 
 the objects that surround us, and from 
 which we may receive so much benefit or 
 harm, is equally necessary to children and 
 to men, to the ignorant and to the learned, 
 God in his wisdom conveys it to us in a 
 way that puts all upon a level. The inform- 
 ation of the senses is as perfect, and gives 
 as full conviction to the most ignorant as to 
 the most learned. 
 
 CHAPTER VI. 
 
 WHAT IT IS TO ACCOUNT FOR A PHENOMENON 
 IN NATURE. 
 
 An object placed at a proper distance, 
 and in a good light, while the eyes are shut, 
 is not perceived at all ; but no sooner do 
 we open our eyes upon it than we have, as 
 it were by inspiration, a certain knowledge 
 of its existence, of its colour, figure, and 
 distance. This is a fact which every one 
 knows. The vulgar are satisfied with know- 
 ing the fact, and give themselves no trouble 
 about the cause of it : but a philosopher is 
 impatient to know how this event is pro- 
 duced, to account for it, or assign its cause. 
 
 This avidity to know the causes of things 
 is the parent of all philosophy, true and 
 false. Men of speculation place a great 
 part of their happiness in such knowledge. 
 
 • See above, p. 128, b, note ♦, and p. 130, b, note • ; 
 a' *Jote A.— H. 
 
 [Hi, 112]
 
 CHAP. VI.] 
 
 ACCOUNT OF A PHENOMENON. 
 
 261 
 
 Felix qui potttit rerum cogno^cere causas, 
 has always been a sentiment of human 
 nature. But, as in the pursuit of otlier 
 kinds of happiness men often mistake the 
 road, so in none have they more frequently 
 done it than in the philosophical pursuit of 
 the causes of things. [113] 
 
 It is a dictate of common sense, that the 
 causes we assign of appearances ought to 
 be real, and not fictions of human imagina- 
 tion. It is likewise self-evident, that such 
 causes ought to be adequate to the eft'eets 
 that are conceived to be produced by them. 
 
 That those who are less accustomed to 
 inquiries into the causes of natural appear- 
 ances, may the better understand what it 
 is to shew the cause of such appearances, 
 or to account for them, I shall borrow a 
 plain instance of a pluienomenon or appear- 
 ance, of which a full and satisfactory ac- 
 count has been given. The phtenomenon 
 is this : That a stone, or any heavy body, 
 falling from a height, continually increases 
 its velocity as it descends ; so that, if it 
 acquire a certain velocity in one second of 
 time, it will have twice that velocity at the 
 end of two seconds, thrice at the end of 
 three seconds, and so on in proportion to 
 the time. This accelerated velocity in a 
 stone falling must have been observed from 
 the beginning of the world ; but the first 
 person, as far as we know, who accounted 
 for it in a proper and philosophical manner, 
 was the famous Galileo, after innumer- 
 able false and fictitious accounts had been 
 given of it. 
 
 He observed, that bodies once put in 
 motion continue that motion with the same 
 velocity, and in the same direction, until 
 they be stopped or retarded, or liave the 
 direction of their motion altered, by some 
 force impressed upon them. This property 
 of bodies is called their inertia, or inac- 
 tivity ; for it implies no more than that 
 bodies cannot of themselves change their 
 state from rest to motion, or from motion 
 to rest. lie observed also, that gravity acts 
 constantly and equally upon a body, and 
 therefore will give equal degrees of velocity 
 to a body in equal times. From these 
 principles, which are known from experi- 
 ence to be fixed laws of nature, Galileo 
 shewed that heavy bodies must descend 
 with a velocity uniformly accelerated, as 
 by experience they arc found to do. [114] 
 
 For if the body by its gravitation ac- 
 quire a certain velocity at the end of one 
 second, it would, thou^^h its gravit.ation 
 should cease that moment, continue to go on 
 with that velocity ; but its gravitation con- 
 tiniifs, and will in another sec^ond give it an 
 additional velocity, eqial totliat wliicli itgave 
 in tlio first ; so that tlic wliolo velocity at 
 tlie end of two secoiids, will be twice as great 
 as at the end of unc In like manner, thiH 
 ril.'i-11.5l 
 
 velocity being contiinied through the third 
 second, and having the same addition by 
 gravitation as in any of the preceding, the 
 whole velocity at the end of the third second 
 will be thrice as great as at the end of the 
 first, and so on continually. 
 
 We may here observe, that the causes 
 assigned of this phsenomenon are two : Firsf, 
 That bodies once put in motion retain their 
 velocity and their direction, until it is changed 
 by some force impressed upon them. Se- 
 coiidly, That the weight or gravitation of a 
 body is always the same. These are laws 
 of Nature, confirmed by universal experi- 
 enee, and therefore are not feigned but true 
 causes. Then, they are precisely adequate 
 to the effect ascribed to them ; they nmst 
 necessarily produce that very motion in 
 descending bodies which wc find to take 
 place ; and neither more nor less. The 
 account, therefore, given of this phisenom- 
 non, is just and philosophical ; no other 
 will ever be required or admitted by those 
 who understand this. 
 
 It ought Ukewise to be observed, that 
 the causes assigned of this phnenomenon, 
 are things of which we can assign no cause. 
 Why bodies once put in motion continue to 
 move — why bodies constantly gravitate to- 
 wards the earth with the same force — no 
 man has been able to shew : these are facts 
 confirmed by universal experience, and 
 they must no doubt have a cause ; but their 
 cause is unknown, and we call them laws 
 of Nature, because we know no cause of 
 them, but the will of the Supreme Being. 
 
 But may we not attempt to find the cause 
 of gravitation, and of other pliEenomena, 
 which we call law.s of Nature ? No doubt 
 we may. [115] We know not the limit which 
 has been set to human knowledge, and our 
 knowledge of the works of God can never 
 be carried too far. lUit, supposing t;ravita- 
 tion to be accounted for, by an lethereal 
 elastic medium, for instance, this can only be 
 done, first, by proving tlie existence and the 
 elasticity of this medium ; and, secimdly, 
 by shewing that this medium must neees- 
 .sarily produce tliiit gravitation which bodies 
 are known to have. Until this be done, 
 gravitation is not accounted for, nor is 
 its cause known ; and when this is done, 
 the elasticity of this medium will be consi- 
 dered as a law of nature wliose cause is 
 unknown. The chain of natural causes has, 
 not unfitly, l)ecn compureil to acli:iin liang- 
 ing down from heaven : a link that is dis- 
 covered supports the links below it, but it 
 nmst itself be supported ; and that which 
 supports it nmst be supported, until we 
 conie to the first link, which is sujjported 
 by the throne of tlie Almighty. F.vcry na- 
 tural cause must have a cause, until wo 
 ascend to tlie first cjume, wiiich is uneaused, 
 and operates nut by necossity but liy will
 
 262 
 
 ON THE INTELLECTUAL POWERS. 
 
 [essay II. 
 
 By what has been said in this chapter, 
 those who are but little acquainted with 
 philosophical inquiries, may see what is 
 meant by accounting for a phcenomenon, 
 or shewing its cause, which ought to be well 
 understood, in order to judge of the theories 
 by which philosophers have attempted to 
 account for our perception of external ob- 
 jects by the senses. 
 
 CHAPTER Vn. 
 
 SENTIMENTS* OF PHILOSOPHERS ABOUT THE 
 PERCEPTION OF EXTERNAL OBJECTS ; AND, 
 FIRST, OF THE THEORY OF FATHER MALE- 
 BRANCHE.-j- 
 
 How the correspondence is carried on 
 between the thinking principle within us, and 
 the material world without us, has always 
 been found a very difficult problem to those 
 philosophers who think themselves obliged 
 to account for every phisenoraenon in nature. 
 [116] Many philosophers, ancient and 
 modern, have employed their invention to 
 discover how we are made to perceive ex- 
 ternal objects by our senses ; and there 
 appears to be a very great uniformity in 
 their sentiments in the main, notwithstand- 
 ing their variations in particular points. 
 
 Plato illustrates our manner of perceiving 
 the objects of sense, in this manner. He 
 supposes a dark subterraneous cave, in 
 which men lie bound in such a manner 
 that they can direct their eyes only to one 
 part of the cave : far behind, there is a 
 light, some rays of which come over a wall 
 to that part of the cave which is before the 
 eyes of our prisoners. A number of per- 
 sons, variously employed, pass between 
 them and the light, whose shadows are seen 
 by the prisoners, but not the persons them- 
 selves. 
 
 In this manner, that philosopher con- 
 ceived that, by our senses, we perceive the 
 shadows of things only, and not things 
 themselves. He seems to have borrowed 
 his notions on this subject, from the Pytha- 
 goreans, and they very probably from Py- 
 thagoras himself. If we make allowance 
 for Plato's allegorical genius, his sentiments 
 on this subject, correspond very well with 
 
 • Sentiment, as here and elsewhere employed by 
 Rcid, in the meaning of opinion, [sententia,] is not 
 to be imitated. There are, undoubtedly, precedents 
 to he found for such usage in English writers ; and, in 
 the French and Italian languages, thi< is one of the 
 ordinary signfications of the word — H 
 
 + It is not easy to conceive hy what principle the 
 order of the Irstory of opinions touching Perception, 
 contained in the nine following chapters, is deter- 
 mined. It is not chronological, and it is not systematic. 
 Of these theories, there is a very able survey, liy M. 
 Royer ( oUard, among the fragments of his lectures, 
 in the third volume of JoufFroy's " Oeuvres de Reid." 
 That distinguished philosopher has, however, placed 
 too great a reliance upon the accuracy of Reid — H. 
 
 those of his scholar, Aristotle, and of the 
 Peripatetics. The shadows of Plato may 
 very well represent the species and phan- 
 tasms of the Peripatetic school, and the 
 ideas and impressions of modern philo- 
 sophers.* 
 
 » This interpretation of the meaning of Plato's 
 comparison of the cave exhibits a curious mistake, 
 in which Reid is followed by Mr Stewart and many 
 others, and which, it is remarkable, has never yet 
 been detected. In the similitude in question, (which 
 will be found in the seventh book of the Republic,) 
 Plato is supposed to intend an illustration of the 
 mode in which the shadows or vicarious images of 
 external things are admitted into the mind — to 
 typify, in short, an hypothesis of sensitive perceptien. 
 On this supposition, the identity of the Platonic, 
 Pythagorean, and Peripatetic theories of this pro- 
 cess is inferred. Nothing can, however, lie more 
 groundless than the supposition ; nothing more erro. 
 neous than the infereme. By his cave, images, and 
 shadows, Plato meant simply to illustrate the grand 
 principle of his philosophy — that the Sensible or Ec. 
 typal world, (phaenomenal, transitory, yiyuiifA.ivov, o» 
 Kot.) f/,vi h,) Stands to the Noetic or Archetypal, (sub. 
 stantial, permanent, oVtms ov,) in the same relation 
 of comparative unreality, in which the shadows of the 
 images of sensible existences themselves, stand to the 
 things of which they are the dim and distant adum- 
 brations. In the language of an illustrious poet — 
 " An nescis, quascunque heic sunt, quje hac nocte 
 
 teguntur. 
 Omnia res prorsus veras non esse, sed umbras, 
 Aut specula, unde ad nos aliena elucet imago ? 
 Terra quidem, et maria alta, atque his circumfluut 
 
 aer, 
 EtqUEe cnnsistunt ex lis, haac omnia tenueis 
 Sunt umbrae, humanos quje tanquam somnia quae. 
 
 dam 
 Pertingunt animos, fallaci et imagine ludunt, 
 Nunquam eadem, fluxu semper variata perenni, 
 Sol autem, Lunseque globus, fulgentiaque astra 
 ("aetera, sint quamvis nieliori prjedita vita, 
 Et donata asvo immortal i, hfec ipsa tamen sunt 
 iEterni specula, in qus animus, qui est inde profec- 
 
 tus, 
 Inspiciens, patriae quodam quasi tactus amore, 
 Ardescit. Verum quoniam heic non perstat et ultra 
 Nescio quid scquitur secum, tacitusque requirit, 
 Nosse licet circuin hsec ipsum consistere verum, 
 Non finem : sed enim esse aliud quid, cujus imago 
 Splendet in iis, quod per se ipsum est, et principium 
 
 esse 
 Omnibus asternum, ante omnem numerumque diem- 
 
 que; 
 In quo alium Solem atque aliam splendescere Lu- 
 
 nam 
 Adspicias, aliosque orbes, alia astra manere, 
 Terramque, fluviosque alios, atque aera, et ignem, 
 Et nemora, atque aliis errare animalia silvi.C 
 
 And as the comparison is misunderstood, so no. 
 thing can be conceived more adverse to the doctrine 
 of Plato than the theory it is supposed to elucidate. 
 Plotinus, indeed, formally refutes, as contrary to the 
 Platonic, the very hypothesis thus attributed to hi« 
 master. (Enn. IV., I. vi., cc, I., 3.) The doctrineof 
 the Platonists o i this point has been almost wholly 
 neglected; and the author among them whose work 
 contains its most articulate developement has been 
 so completely overlooked, both by scholars and phi. 
 losophers, that hi. work is of the rarest, while even 
 his name is mentioned in no history of philosophy. 
 It is here suflScicnt to state, that the eiSaXa, the 
 Xo'yo) yvair'xo), the forms representative of external 
 things, and corresponding to the species semiles ex. 
 pi-essee of the schoolmen, were not held by the Plato, 
 nists to be derived from without, i'rior to the act o( 
 perception, they have a latent but real existence in 
 the soul ; and, by the impassive energy of the mind 
 itself, are elicited into consciousness, on occasion of the 
 impression {!iiv/iiris,rrii.Bo;,ifj.(px<rii) made on theexter. 
 nal organ, and of iheviial form (ilaiTixiv ilim) , in con- 
 sequence thereof, sublimated in the animal life. The 
 verses of Boethius, which have been so frequently 
 mi'^unde^stood, contain an accurate statement of the 
 Platonic theory of perception. After refuting the 
 
 ills']
 
 CHAP. VII.3 
 
 SEN TliMENTS ABOUT PERCEPTION. 
 
 263 
 
 Two thousand years after Plato, Mr 
 Locke, who studied the operations of the 
 human mind so much, and with so great 
 success, representsourmaiiner of perceiving 
 external objects, by a similitude very much 
 resembUng that of the cave. " Methiuks," 
 says he, "the understanding is not much 
 imlike a closet wholly shut from light, with 
 only some little opening left, to let in exter- 
 nal visible resemblances or ideas of things 
 without. Would the pictures coming into 
 such a dark room but stay there, and lie so 
 wderly as to be found upon occasion, it 
 would very much resemble the under- 
 standing of a man, in reference to all objects 
 of sight, and the ideas of them." [117] 
 
 Plato's subterranean cave, and Mr Locke's 
 dark closet, may be applied with ease to all 
 the systems of perception that have been 
 invented : for they all suppose that we 
 perceive not external objects immediately, 
 and that the immediate objects of percep- 
 tion are only certain shadows of the ex- 
 ternal objects. Those shadows or images, 
 which we immediately perceive, were by 
 the ancients called species, forms, phan- 
 tasms. Since the time of Des Cartes, they 
 have commonly been called ideas, and by 
 Mr Hume, impressiuits. But all philoso- 
 phers, from Plato to ]Mr Hume, agree in 
 this. That we do not perceive external ob- 
 jects immediately, and that the immediate 
 object of perception must be some image 
 present to the mind.* So far there ap- 
 
 Stoical doctrine of the passivity of mind in this pro- 
 cess, he proceeds : — 
 
 •' Mens est efficiens magis 
 
 Longe causa potentior, 
 
 Quam quje mateiia; modo 
 
 linpressaB patilur notas. 
 
 Prcecedit tamen excitans 
 
 Ac vires animi movens 
 
 Vivo in corpore passio. 
 
 Cum vel lux oculos ferit, 
 
 Vel vox auribus instrepit: 
 
 Turn mentis vigor excittis 
 
 Quai intus species tenet. 
 
 Ad mollis similes vocans, 
 
 Notis applicat extcris, 
 
 Intronujnquc recondilis 
 
 Formis miscet imagines." 
 I cannot now do more than indicate the contrast 
 of this doctrine to the Peripatetic (I do not say Aris- 
 totelian) theory, and its approximation to the Carte, 
 eiaii and Lcibnitzian hypotheses; which, however, 
 both attempt to explain, what the Platonic did not — 
 how the mind, ex hypolhesi, above all p/iysical in- 
 fluence, is determined, on the presence of the un. 
 known reality within the sphere o( sense, to call into 
 consciousness the representation through which that 
 reality is made known to us. I may add, that not 
 merely the Platoiiisf, but soire of the older I'cripa- 
 tetics held that the soul virtually contained within it. 
 •elf representative forms, which were only excited 
 by the external reality; as 1 licofihrastus and 'l"hc. 
 mislius, to say nothing of the I'latoniziiig Porphyry, 
 Simplicius and Ainraonius llermia;; and the same 
 opinion, adopted probably from the latter, by his 
 pu['il, the Arabian Adelandus, sulxequcntly I'e. 
 came even the common doctrine of the Mooiisli 
 Aristotelians. 
 
 I shall afterwards have occuiim lo notice that 
 Bacon ha> a'so wre!itt'<l Plato's smiiliiude uf the cave 
 from its genuine signification. — H. 
 • J his is not correct. There were philoBophers 
 
 [117, IIB] 
 
 pears an unanimity, rarely to be found among 
 philosophers on such abstruse points.* 
 
 If it should be asked, Whetlier, accord- 
 ing to the opinion of i)hilosophers, we per- 
 ceive the images or ideas only, and infer the 
 existence and qualities of the external ob- 
 ject from what we perceive in the image ; 
 or, whether we really perceive the external 
 object as well as its image ? — the answer 
 to this question is not quite obvious. -f- 
 
 On the one hand, philosophers, if we ex- 
 cept Berkeley and Hume, believe the ex- 
 istence of external objects of sense, and call 
 them objects of perception, though not im- 
 mediate objects. But what they mean by 
 a mediate object of perception I do not find 
 clearly explained : whether they suit their 
 language to popular opinion, and mean that 
 we perceive external objects in that figura- 
 tive sense in which wo say that we perceive 
 an absent friend when we look on his pic- 
 ture ; or whether they mean that, really, 
 and without a figure, we perceive both the 
 external object and its idea in the mind. 
 If the last be their meaning, it would follow 
 that, in every instance of perception, there 
 is a double object perceived: [118] that 
 I perceive, for instance, one sun in the 
 heavens, and another in my own mind.J 
 But I do not find that they affirm this ; 
 and, as it contradicts the experience of all 
 mankind, I will not impute it to them. 
 
 It seems, therefore, that their opinion is. 
 That we do not really perceive the external 
 object, but the internal only ; and that, when 
 they speak of perceiving external objects, 
 they mean it only in a popular or in a figur- 
 ative sense, as above explained. Several 
 reasons lead me to think this to be the 
 opinion of philosophers, beside what is 
 mentioned above. First, If we do really 
 perceive the external object itself, there 
 seems to be no necessity, no use, for an 
 image of it. Seamdly, Since the time of 
 Des Cartes, philosophers have very gene- 
 rally thought that the existence of external 
 objects of sense requires proof, and can only 
 be proved from the existence of their ideas. 
 Thirdly, The way in which philosophers 
 speak of ideas, seems to imply that they 
 are the only objects of perception. 
 
 who held a purer and preciser doctrine of immediate 
 perception than P.cid himself contemplateil. — H. 
 
 * Keid himself, like the philosnphors in general, 
 really hold", that we do not perceive external things 
 immediately, if he does not allow us n consciousness 
 of the non-ei^o. It matters not whether the external 
 reality be represented in n lertium quid, or in a mo- 
 ditication of the mind itself; 111 eitlier case, it is not 
 known in itself, but in somclhing nunutically dif- 
 feteiit.— H. 
 
 t Notliingcan bo clearer than would be this answer. 
 
 In percepiion, tlicr extirnal rrality, (the medi.itc 
 
 object,) is only known lo iis in ami thinugh Iheiin. 
 mediate object, i. c, th( riprcsinlatiim of wbiili we 
 are conscious, .is ixilin^', and beyond thesphere of 
 tonfciousne.vs, the external reality i. unknown. --M. 
 
 t " Kt soliin Kcminuin it dupUcei »e oslendere 
 Thebas!"— II.
 
 204 
 
 ON THE INTELLECTUAL POWERS. 
 
 |_EssAv ir. 
 
 Having endeavoured to explain what is 
 common to philosophers in accounting for 
 our perception of external objects, we shall 
 give some detail of their differences. 
 
 The ideas by which we perceive external 
 objects, are said by some to be the ideas of 
 the Deity ; but it has been more generally 
 thought, that every man's ideas are proper 
 to himself, and are either in his mind, or 
 in his sensorium, where the mind is imme- 
 diately present. The first is the theory of 
 Malebranche ; the second we shall call the 
 common theory. 
 
 With regard to that of Malebranche, it 
 seems to have some affinity with the Pla- 
 tonic notion of ideas,* but is not the same. 
 Plato believed that there are three eternal 
 first principles, from which all things have 
 their origin — matter, ideas, and an efficient 
 cause. Matter is that of which all things 
 are made, which, by all the ancient philo- 
 sophers, was conceived to be eternal. [119] 
 Ideas are forms without matter of every 
 kind of things which can exist ; which forms 
 were also conceived by Plato to be eternal 
 and immutable, and to be the models or 
 patterns by which the efficient cause — that 
 is, the Deity — formed every part of this 
 universe. These ideas were conceived to 
 be the sole objects of science, and indeed 
 of all true knowledge. While we are iui- 
 prisoned in the body, we are prone to give 
 attention to the objects of sense only ; but 
 these being individual things, and in a con- 
 stant fluctuation, being indeed shadows 
 rather than realities, cannot be the object 
 of real knowledge. All science is employed 
 not about individual things, but about 
 things universal and abstract from matter. 
 Truth is eternal and immutable, and there- 
 fore must have for its object eternal and 
 immutable ideas ; these we are capable of 
 contemplating in some degree even in our 
 present state, but not without a certain 
 purification of mind, and abstraction from 
 the objects of sense. ' Such, as far as I am 
 able to comprehend, were the sublime 
 notions of Plato, and probably of Pytha- 
 goras. 
 
 The philosophers of the Alexandrian 
 school, commonly called the latter Plato- 
 nists, seem to have adopted the same sys- 
 tem ; but with this difference, that they 
 made the eternal ideas not to be a principle 
 distinct from the Deity, but to be in the 
 divine intellect, as the olijects of those con- 
 ceptions which the divine mind must, from 
 all eternity, have had, not only of every- 
 
 » The Platonic theory of Ideas has nothing to do 
 with a docfriiie of sensitive perception ; and its intro. 
 duction into the question is only pregnant with con. 
 fusion; while, in regard to sensitive perception, the 
 peculiar hyjjothesis of Malebranche, is in tact not only 
 not similar to, but much farther removed from, the 
 Platonic than the common I artesian theory, and 
 the I/Oibnitzian— H. 
 
 thing which he has made, but of every pos- 
 sible existence, and of all the relations of 
 things.* By a proper purification and 
 abstraction from the objects of sense, we 
 may be in some measure united to the 
 Deity, and, in the eternal light, be enabled 
 to discern the most sublime intellectual 
 truths. 
 
 These Platonic notions, grafted upon 
 Christianity, probably gave rise to the 
 sect called Mystics, which, though in its 
 spirit and principles extremely opposite to 
 the Peripatetic, yet was never extinguished, 
 but subsists to this day, [120] 
 
 Many of the Fathers of the Christian 
 church have a tincture of the tenets of the 
 Alexandrian school ; among others, St 
 Augustine. But it does not appear, as far 
 as I know, that either Plato, or the latter 
 Platonists, or St Augustine, or the Mystics, 
 thought that we perceive the objects of 
 sense in the divine ideas. They had too 
 mean a notion of our perception of sensible 
 objects to ascribe to it so high an origin. 
 This theory, therefore, of our perceiving 
 the objects of sense in the ideas of the 
 Deity, I take to be the invention of Father 
 Malebranche himself. He, indeed, brings 
 many passages of St Augustine to counte- 
 nance it, and seems very desirous to have 
 that Father of his party. But in those 
 passages, though the Father speaks in a 
 very high strain of God's being the light of 
 our minds, of our being illuminated imme- 
 diately by the eternal light, and uses other 
 similar expressions ; yet he seems to apply 
 those expressions only to our illumination 
 in moral and divine things, and not to the 
 perception of objects by the senses. Mr 
 Bayle imagines that some traces of this 
 opinion of Malebranche are to be found in 
 Amelius the Platonist, and even in Demo- 
 critus ; but his authorities seem to be 
 strained. -f- 
 
 INIalebranche, with a very penetrating 
 genius, entered into a more minute examin- 
 ation of the powers of the human mind, 
 than any one before him. He had the advan- 
 tage of the discoveries made by Des Cartes, 
 whom he followed without slavish attach- 
 ment. 
 
 He lays it down as a principle admitted 
 by all philosophers, and which could not 
 be called in question, that we do not per- 
 ceive external objects immediately, but by 
 means of images or ideas of them present 
 to the mind. " I suppose," says he, " that 
 
 » And this, though Aristotle asserts the contrary, 
 was perhaps also the doctrine of Plato. — H. 
 
 t ' he theory of Malebranche has bpen vainly 
 sought for in the Bil)le,the Platonists, and the Fathers. 
 It IS, in fact, more clearly enounced in Homer than 
 in any of these graver sources. 
 
 Tiro? yoiP vooi Ifiv iTix^iivictiv oc^&^aiTCiiVy 
 Oiov It rjicccp u.yy,a't Tocrrg «v3g^v t6 5ewv t£- 
 
 :.:._.= _.-_ -_ V,... 0,_^^ 
 
 But for anticipations, see Note P.- 
 
 [119, 120]
 
 ujAP. VII.] SENTIMENTS ABOUT EXTERNAL OBJECTS. 
 
 265 
 
 every one will grant that we perceive not 
 tlie objects that are without us immediately, 
 and of themselves." We see the sun, the 
 stars, and an infinity of objects without us ; 
 and it is not at all likely that the soul sal- 
 lies out of the body, and, as it were, takes a 
 walk through the heavens, to contemplate 
 all those objects. [121] She sees them not, 
 therefore, by themselves; and the imme- 
 diate object of the mind, when it sees the 
 sun, for example, is not the sun, but some- 
 thing which is intimately united to the 
 soul ; and it is that which I call an idea. 
 So that by the word idea, I understand 
 nothhig else here but that which is the im- 
 mediate object, or nearest co the mind, 
 when we perceive-f- any object.:|: It ought 
 to be carefully observed, that, in order to 
 tlie mind's perceiving any object, it is abso- 
 lutely necessary that the idea of that ob- 
 ject be actually present to it. Of this it 
 
 is not possible to doubt 
 
 Tlie things which the soul perceives are of 
 two kinds. They are either in the soul, or 
 they are without the soul. Those that are 
 in the soul are its own tlioughts — that is to 
 say, all its different modifications. [For 
 by these words — thought, maimer of think' 
 i)ig, or mor/iJicatij?i of the soul, I under- 
 etand in general whatever cannot be in the 
 mind without the mind perceiving it, as its 
 proper sensations, its imaginations, its pure 
 intellections, or simply its conceptions, its 
 passions even, and its natural inclina- 
 tions. ] § The soul has no need of ideas for 
 perceiving these things. || But with regard 
 to things without the soul, we cannot per- 
 ceive them but by means of ideas.''5[ 
 
 Having laid this foundation, as a prin- 
 ciple common to all philosophers, and which 
 admits of no doul)t, he proceeds to enume- 
 rate all the possible ways by which the ideas 
 of sensible objects may be presented to the 
 mind : Either, fiist, they come from tlie 
 bodies which we perceive ;• • or, secondly, the 
 80ul has the power of producing them in it- 
 self ;-f--|- or, th'rdli/, they are produced by the 
 
 • Rather in or by l/iemselvei {par eux memea.) 
 — H. 
 
 f That is, in the language of philosophers before 
 Reiti, " where we have the apprehensive cognition 
 or conscious'iess of any object."— H. 
 
 X In this ilefinitio'i, all philosophers concur. Dcs 
 Cartes, Locke, S:c., give it in almost the same terms. 
 -H. 
 
 ^ I have inserted this sentence, omitted by Reid, 
 from the original, in order to shew in how exten. 
 give a meaning the term Ihuughl wai used in the 
 Cartesian school SeeCartenii I'riiic , I'. I., \ 9. — H. 
 
 II Heme the distinction precisely tak( n by Male, 
 branclie of Idea {idie) and Feeling, (scntimnit,) cor. 
 responding in principle to our I'erception of the 
 primary, and our Sejisation of the secondary qualities 
 
 — H. 
 
 ^ licln licchcrche lie la Vcriti. I.iv. III., Partie 
 ii.,ch. I — H. 
 
 «• The common Peripatetic (lo( trine, &c — II. 
 
 ft MalebraTiche refers, I iiresumo, to the opiinoni 
 fit certain Cartesians. See Oasseiidi Opera, iii. p :ji^l. 
 
 — H. 
 
 Deity, either in our creation, or occasionally, 
 as there is use for them ;* or, fourthly, tlie 
 soul has in itself virtually and eminently, as 
 the schools speak, ail the perfections w"liich 
 it perceives in bodies ;t or, Jifthly, the soul 
 is united with a Being possessed of all per- 
 fection, who has in himself the ideas of all 
 created things. 
 
 This he takes to be a complete enumera- 
 tions of all the possible ways in which the 
 ideas of external objects may be presented 
 to our minds. He employs a whole chapter 
 upon each ; refuting the four first, and con- 
 firming the last by various arguments. 
 The Deity, being always present to our 
 minds in a more intimate manner than any 
 other being, may, upon occasion of the im- 
 pressions made on our bodies, discover to us, 
 as far as he thinks proper, and according 
 to fi.xed laws, his own ideas of the object ; 
 and thus we see all things in God, or in the 
 divine ideas.:}: [122] 
 
 However visionary this system may ap- 
 pear on a superficial view, yet, when we 
 consider that he agreed with the whole tribe 
 of philosophers in conceiving ideas to be the 
 immediate objects of perception, and that 
 he found insuperable difficulties, and even 
 absurdities, in every other hypothesis con- 
 cerning them, it will not appear so wonder- 
 ful that a man of very great genius should 
 fall into this ; and, probably, it pleased 
 so devout a man the more, that it sets, in 
 the most striking light, our dependence upon 
 God, and his continual presence with us. 
 
 He distinguished, more accurately than 
 any philosopher had done before, tlie objects 
 which we perceive from the sensations in 
 our .own minds, which, by the laws of 
 Nature, always accompany the perception 
 of the object. As in many things, so par- 
 ticularly in this, he has great merit. For 
 this, I apprehend, is a key that opens the 
 way to a right understanding, both of our 
 external senses and of other powers of the 
 mind. The vulgar confound sensation with 
 other powers of the mind, and with their 
 objects, because the purjioses of life do not 
 make a distinction necessary. The con- 
 founding of these in common language, has 
 led philo.sophors, in one period, to make 
 tho.se things external whicli really are sens- 
 ations ill our own minds ; and, in another 
 period, running, as is usual, into the cou- 
 
 • Opiniois analogous to the second or third, were 
 held by the I•l,^toni^ts, by some ot the (ireek, and 
 by many of the Arabian Arisiolelians. .See bove, p. 
 '^^^)•^, note • — H. 
 
 f .Something similar to this is hazarded by Oci 
 Carte* in his Third " .Meditation,' which it is likely 
 thai Malibranche had in his eye. — II 
 
 X It should have been noticed that i he Malebrnnch. 
 Ian philoN(i|ihy is fuiidami ntally i ailchian, and that. 
 after lie la Korge and (ieulinx, the doclriiie ol 
 Divine A^siiliiuii-, iniplieiily mainlained by l)c» 
 (arlen, w IS must ably develiipul by Malebrnnclie, to 
 whom it owes, indeed, a prnicii>al share of ili eel. 
 bntv.— II.
 
 266 
 
 ON THE INTELLECTUAL POWERS. 
 
 [essay II 
 
 trary extreme, to make everything almost 
 to be a sensation or feeling in our minds. 
 
 It is obvious that the system of Male- 
 branche leaves no evidence of the existence 
 of a material world, from what we perceive 
 by our senses ; for the divine ideas, which 
 are the objects immediately perceived, were 
 the same before the world was created. 
 Malebranche was too acute not to discern 
 this consequence of his system, and too can- 
 did not to acknowledge it. [123] He fairly 
 owns it, and endeavours to make advantage 
 of it, resting the complete evidence we have 
 of the existence of matter upon the author- 
 ity of revelation. He shews that the argu- 
 ments brought by Des Cartes to prove the 
 existence of a material world, though as 
 good as any that reason could furnish, are 
 not perfectly conclusive ; and, though he 
 acknowledges with Des Cartes that we feel 
 a strong propensity to believe the existence 
 of a material world, yet he thinks this is 
 not sufficient ; and that to yield to such 
 propensities without evidence, is to expose 
 ourselves to perpetual delusion. He thinks, 
 therefore, that the only convincing evidence 
 we have of the existence of a material world 
 is, that we are assured by revelation that 
 God created the heavens and the earth, 
 and that the Word was made flesh. He is 
 sensible of the ridicule to which so strange 
 an opinion may expose him among those 
 who are guided by prejudice ; but, for the 
 sake of truth, he is willing to bear it. But 
 no author, not even Bishop Berkeley, hath 
 shewn more clearly, that, either upon his 
 own system, or upon the common principles 
 of philosophers with regard to ideas, we 
 have no evidence left, either from reason 
 or from our senses, of the existence of a 
 material world. It is no more than justice 
 to Father Malebranche, to acknowledge that 
 Bishop Berkeley's arguments are to be 
 found in him in their whole force. 
 
 Mr Norris, an English divine, espoused 
 the system of Malebranche, in his " Essay 
 towards the Theory of the Ideal or Intel- 
 lectual World," published in two volumes 
 8°, anno I70I. This author has made a 
 feeble effort to supply a defect which is to 
 be found not in Malebranche only, but in 
 almost all the authors who have treated of 
 ideas — I mean, to prove their existence.* 
 He has employed a whole chapter to prove 
 that material things cannot be an immediate 
 object of perception. His arguments are 
 these : Is/, They are without the mind, and, 
 therefore there can be no union between the 
 object and the perception. 2dly, They are 
 disproportioned to the mind, and removed 
 
 * This is incorrect. In almost every system of 
 the Aristotelico-scholastic philosophy, the attempt is 
 made to prove the existence of Species ; nor is Reid's 
 ;isseition true even of ideas in the Cartesian philoso- 
 phy. In fact, Norris's arguments are all old and 
 commonplace. — H. 
 
 from it by the whole diameter of being. 
 3rf^//, Because, if material objects were 
 immediate objects of perception, there could 
 be no physical science; things necessary 
 and immutable being the only objects of 
 science. [124] 4/A/y, If material things were 
 perceived by themselves, they would be a 
 true light to our minds, as being the intel- 
 ligible form of our understandings, and con- 
 sequently perfective of them, and, indeed, 
 superior to them. 
 
 Malebranche's system was adopted by 
 many devout people in France of both 
 sexes ; but it seems to have had no great 
 currency in other countries, Mr Locke 
 wrote a small tract against it, which is 
 found among his posthumous works :* but, 
 whether it was written in haste, or after 
 the vigour of his understanding was im- 
 paired by age, there is less of strength and 
 solidity in it than in most of his writings. 
 The most formidable antagonist Male- 
 branche met with was in his own country — 
 Antony Arnauld, doctor of the Sorbonne, 
 and one of the acutest writers the Jansenists 
 have to boast of, though that sect has pro- 
 duced many. Malebranche was a Jesuit, 
 and the antipathy between the Jesuits and 
 Jansenists left him no room to expect 
 quarter from his learned antagonist.-)- Those 
 who choose to see this system attacked on 
 the one hand, and defended on the other, 
 with subtilty of argument and elegance of 
 expression,^! and on the part of Arnauld 
 with much wit and humour, may find satis- 
 faction by reading Malebranche's " Enquiry 
 after Truth ;" Arnauld's book " Of True and 
 False Ideas ;" Malebranche's " Defence ;" 
 and some subsequent replies and defences. 
 In controversies of this kind, the assailant 
 commonly has the advantage, if they are 
 not unequally matched ; for it is easier to 
 overturn all the theories of philosophers 
 upon this subject, than to defend any one 
 of them. Mr Bayle makes a very just re- 
 mark upon this controversy — that the argu- 
 ments of Mr Arnauld against the system of 
 Malebranche, were often unanswerable, but 
 
 • In answer to Locke's*' Examination of P. Male* 
 branche's Opinion," Leibnitz wrote " Remarks," 
 which are to be found among his posthumous works, 
 publislied by Raspc. — H. 
 
 + Malebranche was not a Jesuit, but a Priest of the 
 Oratory; and so little was he either a favourer or 
 favourite of the Jesuits, that, by the Pere de Valois, 
 he was accused ot heresy, by the Fere Hardouin, of 
 Atheism. The endeavours of the Jesuits in France to 
 prohibit the introduction of every form of the Carte- 
 sian dot-trine into the public seminaries of education, 
 are well known. Malebranche and Arnauld were 
 therefore not opposed as Jesuit and Jansenist, and it 
 should likewise be remembered that they were both 
 Cartesians. — H. 
 
 t Independently of his principal hypothesis alto- 
 gether, the works of Malebranche deserve the most 
 attentive study, both on account of the m.nny ad. 
 mirable thoughts and observations with which they 
 abound, and because they are among the few con- 
 summate models of philoscphical eloquence— H. 
 
 ri23, 124]
 
 CHAP, viii.] OF THE THEORY OF PERCEPTION, &c. 
 
 267 
 
 they were capable of being retorted against 
 his owTi system ; and his ingenious antag- 
 onist knew well how to use this defence. L 125] 
 
 CHAPTER VIII. 
 
 OP THE COMMON' THEORY OF PERCEPTION, 
 AND OF THE SENTIMENTS OF THE PERIPA- 
 TETICS, AND OF DES CARTES. 
 
 This theory, in general, is, that we per- 
 ceive external objects only by certain images 
 which are in our minds, or in the sensorium 
 to which the mind is immediately present. 
 Philosophers in different ages have differed 
 both in the names they have given to those 
 images, and in their notions concerning 
 them. It would be a laborious task to 
 enumerate all their variations, and per- 
 haps would not requite the lal^our. I shall 
 only give a sketch of the principal dif- 
 ferences with regard to their names and 
 their nature. 
 
 By Aristotle and the Peripatetics, the 
 images presented to our senses were called 
 sensible species or forms ; those presented 
 to the memory or imagination were called 
 phantasvis ; and those presented to the 
 intellect were called intelligible species ; 
 and tliey thought that there can be no 
 perception, no imagination, no intellection, 
 without species or phantasms,* What the 
 ancient philosophers called species, sensible 
 and intelligible, and phantasms, in later 
 times, and especially since the time of Des 
 Cartes, came to be called by the common 
 name of ideas.-\' The Cartesians divided 
 our ideas into three classes — those of sensa- 
 tion, oi imagination, and oi pure intellection. 
 Of the objects of sensation and imagination, 
 they thought the images are in the brain ; J 
 but of objects that are incorporeal the 
 images are in the understanding or pure 
 intellect. 
 
 JMr Locke, taking the word idea in the 
 same sense as Des Cartes had done before 
 him, to signify whatever is meant by phan- 
 tasm, notion, or species, divides ideas into 
 those of sensation, and those of reflection ; 
 meaning by the first, the ideas of all corpo- 
 real oljjects, whether perceived, remem- 
 bered, or imagined ; by the second, the 
 ideas of the powers and operations of our 
 minds. [12(>] What Mr Locke calls ideas, 
 Mr Hume divides into two distinct kinds, 
 impressions and ideas, 'i'ho diHcrcnce be- 
 twixt these, he says, consists in the degrees 
 of force and liveliness with which they strike 
 upon the mind. Under im/iressions he com- 
 preiicnds all our sensations, passions, and 
 
 • Ste Ni te M H. 
 
 1 N ot intrely rspeciiilly, but inly »lncc the time of 
 I)i» C^rtus, ice Nolp (i.— l\. 
 t Incorrect. Sec Note N.— H. 
 
 [ \'^r,, i?fi] 
 
 emotions, as they make their first appear- 
 ance in the soul. By ideas, he means the 
 faint images of these in thinking and rea- 
 soning. 
 
 Dr Hartley gives the same meaning to 
 ideas as Mr Hume does, and what Mr 
 Hume calls impressions he calls sensations ; 
 conceiving our sensations to be occasioned 
 by vibrations of the infinitesimal particles 
 of the brain, and ideas by miniature vibra- 
 tions or vibratiuncles. Such dift'erences 
 we find among philosophers, with regard to 
 the name of those internal images of objects 
 of sense which they hold to be the imme- 
 diate objects of perception." 
 
 We shall next give a short detail of the 
 sentiments of the Peripatetics and Carte- 
 sians, of Locke, Berkeley, and Hume, con- 
 cerning them. 
 
 Aristotle seems to have thought that the 
 soul consists of two parts, or rather that 
 we have two souls — the animal and the ra- 
 tional ; or, as he calls them, the soul and 
 the intellect. -|- To the first, belong the 
 senses, memory, and imagination ; to the 
 last, judgment, opinion, belief, and reason- 
 ing. The first we have in common with 
 brute animals ; the last is peculiar to man. 
 The animal soul he held to be a certain 
 form of the body, which is inseparable from 
 it, and perishes at death- To this soul the 
 senses belong ; and he defines a sense to be 
 that which is capable of receiving the sensi- 
 ble forms or species of objects, without any 
 of the matter of them ; as wax receives the 
 form of the seal without any of the matter 
 of it. The forms of sound, of colour, of 
 
 * Heid, 1 may ohserve in general, does not dis- 
 tinguish, as it especially lichoved him to do, between 
 wliat were held by philosophers to be the proximate 
 causes of our mental representations, and those 
 representations themselves as'the ubjfcts of cognition 
 — i. e , between what are known in the schools as 
 \hc spfcies itnpesste, ami the specitsexprt's>ir. 'i'he 
 former, to wliich the name of species, image, idea, 
 was otteti given, in common with the latter, was held 
 on all hands to be unknown lo consciousness, and 
 generally supposed to lie merely certain occult motions 
 in the organism. 'Jhe latter, the result deurmincd 
 by the former, is tlie meiit.';! repieseiilalion, and 
 the immediate or proper object in perception, (ireat 
 confusion, to those who do i.ut bear this distinction in 
 mind, is, hoivevir, the consequence of the verbal 
 ambiguity; and Keid's misrepresentations of the 
 dnctrine of the philosophers in, in a great measure, to 
 be traced to this source. — H. 
 
 f This not correct. Inste.id nl two, XhcanimnI and 
 raliunal, Aristotle gave to the soul three gt neric 
 lunctions, the vegetable, the animal or tensnat, anil 
 the rational; but whether he sii|.|'oes these to 
 constitute three coiicciilric potences, three se|.arate 
 iiarts, or three distinct kiuIs, has divided his disciples. 
 He also deliiies the soul in general, and not, (ih Heid 
 supposes, the mere' rtnim'il soul,' lo be the lorin or 
 (►T(Aix</(xof the body, — [IJe .nimai.ii c I.) In- 
 tellect (►»() he however thought W.18 ii, organic: but 
 there is some grouml lor believing thai he ilid not 
 \iew this as peisoiial, but iiarlx.ured an ripniioii 
 which, under v.irious nindilicalioiis, inaiiy of I. is fol 
 lowers also held, Iha' the active intellect was com- 
 mon to all men, immortal and divine. Km? ^a; tiv( 
 T««T« TO iv v,fjLtv th'ic** Xoycv h' onx*- '***' ^oytf ac>.\* rt 
 KfUTTtt ri mt if x{uTro» kk'i itrifii/itu i/TOii TA>,f 
 flief i — II.
 
 268 
 
 ON THE INTELLECTUAL POWERS. 
 
 £essay II. 
 
 taste, and of other sensible qualities, are, 
 in manner, received by the senses. • [ 127 ] 
 
 It seems to be a necessary consequence 
 of Aristotle's doctrine, that bodies are con- 
 stantly sending forth, in all directions, as 
 many different kinds of forms without 
 matter as they have different sensible qua- 
 lities ; for the forms of colour must enter 
 by the eye, the forms of sound by the ear, 
 and so of the other senses. This, accord- 
 ingly, was mamtained by the followers of 
 Aristotle, though not, as far as I know, 
 expressly mentioned by himself. + They 
 disputed concerning the nature of those 
 forms of species, whether they were real 
 beings or nonentities ;J and some held 
 them to be of an intermediate nature be- 
 tween the two. The whole doctrine of the 
 Peripatetics and schoolmen concerning 
 forms, substantial and accidental, and con- 
 cerning the transmission of sensible species 
 from objects of sense to the mind, if it be 
 at all intelligible, is so far above my com- 
 prehension that I should perhaps do it in- 
 justice, by entering into it more minutely. 
 Malebranche, in his " Recherche de la 
 Verite," has employed a chapter to shew 
 that material objects do not send forth 
 sensible species of their several sensible 
 qualities. 
 
 The great revolution which Des Cartes 
 produced in philosophy, was the effect of a 
 superiority of genius, aided by the circum- 
 stances of the times. Men had, for more 
 than a thousand years, looked up to Ari- 
 stotle as an oracle in philosophy. His 
 authority was the test of truth. The small 
 remains of the Platonic system were con- 
 fined to a few mystics, whose principles and 
 manner of life drew little attention. The 
 feeble attempts of Ramus, and of some 
 others, to make improvements in the sys- 
 tem, had little effect. The Peripatetic 
 doctrines were so interwoven with the whole 
 system of scholastic theology, that to dissent 
 from Aristotle was to alarm the Church. 
 The most useful and intelligible parts, 
 even of Aristotle's writings, were neglected, 
 and philosophy was become an art of speak- 
 ing learnedly, and disputing subtilely, with- 
 out producing any invention of use in human 
 life. It was fruitful of words, but barren 
 of works, and admirably contrived for 
 drawing a veil over human ignorance, and 
 
 « See Note M.— H. 
 
 t Nor is there valid ground for supposing that such 
 an opinion was even implicitly held by the Stagirite. 
 It was also explicitly npuiilated by many of his fol. 
 lowers. See Note M. — H. 
 
 X The question in the schools, between those who 
 admitted species, was not, whether species, in gene, 
 ral, were real beings or nonentilt>'s (which would 
 have been, did they exist or not,) but whether sen. 
 si le species were material, immaterial, or of a 
 nature between body and spirit — a problem, it must 
 b ' allowed, sufficiently futile, but not, like the other, 
 self.contradictovy, — n. 
 
 putting a stop to the progress of knowledge, 
 by filling men with a conceit that they 
 knew everything. [128] It was very fruitful 
 also in controversies ; but, for the most part, 
 they were controversies about words, or 
 about things of no moment, or things above 
 the reach of the human faculties. And the 
 issue of them was what might be expected — 
 that the contending parties fought, without 
 gaining or losing an inch of ground, till they 
 were weary of the dispute, or their atten- 
 tion was called off to some other subject.* 
 
 Such was the philosophy of the schools of 
 Europe, during many ages of darkness and 
 barbarism that succeeded the decline of the 
 Roman empire; so that there was great 
 need of a reformation in philosophy as well 
 as in religion. The light began to dawn at 
 last ; a spirit of inquiry sprang up, and 
 men got the courage to doubt of the dogmas 
 of Aristotle, as well as of the decrees of 
 Popes. The most important step in the 
 reformation of religion, was to destroy 
 the claim of infallibility, which hindered 
 men from using their judgment in matters 
 of religion ; and the most important step in 
 the reformation of philosophy, was to destroy 
 the authority of which Aristotle had so long 
 had peaceable possession. The last had 
 been attempted by Lord Bacon and others, 
 with no less zeal than the first by Luther 
 ai!d Calvin, 
 
 Des Cartes knew well the defects of the 
 prevailing system, which had begun to lose 
 its authority. His genius enabled him, and 
 his spirit prompted him, to attempt a new 
 one. He had applied much to the mathe- 
 matical sciences, and had made considerable 
 improvement in them. He wished to in- 
 troduce that perspicuity and evidence into 
 other branches of philosophy which he 
 found in them. 
 
 Being sensible how apt we are to be led 
 astray by prejudices of education, he thought 
 the only way to avoid error was to resolve 
 to doubt of everything, and hold everything 
 to be uncertain, even those things which 
 he had been taught to hold as most certain, 
 until he had such clear and cogent evidence 
 as compelled his assent. [129] 
 
 In this state of universal doubt, that 
 which first appeared to him to be clear and 
 certain, was his own existence. Of this he 
 was certain, because he was conscious that he 
 thought, that he reasoned, and that he 
 doubted. He used this argument, there- 
 fore, to prove his own existence, Cocjito, 
 ergo sum. This he conceived to be the first 
 of all truths, the foundation-stone upon 
 which the whole fabric of human knowledge 
 
 * This is the vulgar opinion in regard to the 
 scholastic pliilosophy. The few are, however, now 
 aware that the human mind, though partially, was 
 never more powerfully developed than during the 
 middle ages.— f I. 
 
 [127-129]
 
 CHAP. VIII.] OF THE THEORY OF PERCEPTION & 
 
 «c. 
 
 2<J9 
 
 is built, and on which it must rest." And, 
 as Archimedes thought that, if he had one 
 fixed poiut to rest his engines upon, he 
 could move the earth ; so Des Cartes, 
 charmed with the discovery of one certain 
 principle, by which he emerged from the 
 state of universal doubt, beUeved that this 
 principle alone would be a sufficient found- 
 ation on which he might build the whole 
 system of science. He seems, therefore, to 
 have taken no great trouble to examine 
 whether there might not be other first prin- 
 ciples, which, on account of their own liglit 
 and evidence, ought to be admitted by 
 every man of sound judgment. -f- The love 
 of simplicity so natural to the mind of man, 
 led him to apply the whole force of his mind 
 to raise the fabric of knowledge upon this 
 one principle, rather than seek a broader 
 foundation. 
 
 Accordingly, he does not admit the evi- 
 dence of sense to be a first principle, as he 
 does that of consciousness. The argu- 
 ments of the ancient sceptics here occurred 
 to him, that our senses often deceive us, 
 and therefore ought never to be trusted on 
 their own authority : that, in sleep, we often 
 seem to see and hear things which we are 
 convinced to have had no existence. But 
 that which chiefly led Des Cartes to think 
 that he ought not to trust to his senses, 
 without proof of their veracity, was, that he 
 took it for granted, as all philosophers had 
 done before him, that he did not perceive 
 external objects themselves, but certain 
 images of them in his own mind, called 
 ideas. He was certain, by consciousness, 
 that he had the ideas of sun and moon, 
 earth and sea ; but how could he be assured 
 that there really existed external objects 
 like to these ideas PJ [130] 
 
 Hitherto he was uncertain of everything 
 but of his own existence, and the existence 
 of the operations and ideas of his own mind. 
 Some of his disciple^ it is said, remained at 
 this stage of his system, and got the name 
 of Egoists. § They could not find evidence 
 in the subsequent stages of his progress. 
 But Des Cartes resolved not to stop here ; 
 he endeavoured to prove, by a new argu- 
 ment, drawn from his idea of a Deity, the 
 existence of an infinitely perfect Being, who 
 made him and all his faculties. From the 
 perfection of this Being, lie inferred that he 
 could be no deceiver ; and therefore con- 
 cluded that his senses, and the other facul- 
 ties he found in liimself, are not fallacious, 
 
 • On the Cartesian doubt, see Note R. — H. 
 
 t '11)18 cannot justly be aflirmed of l)e« Cartes. 
 — H 
 
 ; On thin point II is probable that Dos Cartes and 
 Rfid are at one. .S<e Notes C and N H. 
 
 ^ I am doubtful about the existence o( this sup. 
 poEed fccct of i;»(0«tii. 'J he Chevalier Kamsay, 
 at>ove a century ago, incidentally speaks of this doc. 
 trine as an offiihoot of Spinozisni, and under the 
 
 [i.io, i:n] 
 
 but may be trusted, when a proper use is 
 made of them. 
 
 The system of Des Cartes is, with great 
 perspicuity and acuteness, explained by 
 himself in his writings, which ought to be 
 consulted by those who would understand it. 
 
 The merit of Des Cartes cannot be easily 
 conceived by those who have not some 
 notion of the Peripatetic system, in which 
 he was educated. To throw oft" the preju- 
 dices of education, and to create a system of 
 nature, totally difterent from that which 
 had subdued the understanding of mankind, 
 and kept it in subjection for so many cen- 
 turies, required an uncommon force of mind. 
 
 The world which Des Cartes exhibits to 
 our view, is not only in its structure very 
 different from that of the Peripatetics, but 
 is, as we may say, composed of dilierent 
 materials. 
 
 In the old system, everything was, by a 
 kind of metaphysical sublimation, resolved 
 into principles so mysterious that it may be 
 a question whether they were words with- 
 out meaning, or were notions too refined for 
 liuman understanding. 
 
 All that we observe in nature is, accord- 
 ing to Aristotle, a constant succession of 
 the operations of generation and corruption. 
 [131 ] The principles of generation are mat- 
 ter and form. The principle of corruption is 
 privation. All natural things are produced 
 or generated by the union of matter and 
 form ; matter being, as it were, the mother, 
 and form the father. As to matter, or the 
 first matter, as it is called, it is neither 
 substance nor accident ; it has no quality 
 or property ; it is nothing actually, but 
 everything potentially. It has so strong 
 an appetite for form, that it is no sooner 
 divested of one form than it is clothed with 
 another, and is equally susceptibie of all 
 forms successively. It has no nature, but 
 only the capacity of having any one. 
 
 This is the account which the Peripate- 
 tics give of the first matter. The other 
 jirinciple of generation is, form, act, ptrfer- 
 liiin ; for these three words signify the same 
 thing. But we must not conceive form to 
 consist in the figure, size, arrangement, or 
 motion of the parts of matter. These, in- 
 deed, are accidental forms, by which things 
 
 Mime o( Ei;omisme. But Father Buflier, about the 
 same time, and, be it noted, in a work publishtnl sonic 
 ten years before Hume's " 1 riatise of Human Na- 
 tuie," talks of it, on hearsay, :is the speculation ol a 
 Scotch phdosopher:—" Unccrivain I cossoisapublii', 
 dit on. 111! ouvtageiKiur prouver (ju'il n'avolt nuiunc 
 Evidence de I'txistence d'aucun etre i|uedelui; ct 
 encoie de lui, en taiH iju' esprit; n'aiant aucune <le- 
 monstratioii veritable de iVxistence d'autun cor,i»." 
 
 t',lf7Hcns df Mitiiplii/siqiir, { (il. Now, we know 
 
 that there is no such work. I ain aware, liowevir, 
 that there is mine discussion lai (his point'in Ihu 
 " .Meiiioiis (le '1 revoux,"anno I7I.(, \>.\fii ; to which 
 however, I inntt reler the reader, as I have not thai 
 journal at baud. — Hut more of this below, niiuvf 
 p 1«7.— II.
 
 270 
 
 ON THE rNTELLECTUAL POWERS. 
 
 [essay 
 
 artificial are formed : but every production 
 of Nature has a substantial form," which, 
 joined to matter, makes it to be what it is. 
 The substantial form is a kind of informing 
 soul, which gives the thing its specific na- 
 ture, and all its qualities, powers, and 
 activity. Thus the substantial form of 
 heavy bodies, is that which makes them 
 descend ; of light bodies, that which makes 
 them ascend. The substantial form of 
 gold, is that which gives it its ductility, its 
 fusibility, its weight, its colour, and all its 
 qualities ; and the same is to be understood of 
 every natural production. A change in the 
 accidental form of any body, is alteration 
 only ; but a change in the substantial form 
 is generation and corruption : it is corrup- 
 tion with respect to the substantial form, of 
 which the body is deprived ; it is genera- 
 tion with respect to the substantial form 
 that succeeds. Thus, when a horse dies 
 and turns to dust, the philosophical account 
 of the phcenomenon is this : — A certain por- 
 tion of the materia prima, which was joined 
 to the substantial form of a horse, is de- 
 prived of it by privation, and in the same 
 instant is invested with the substantial form 
 of earth. [132] As every substance must 
 have a substantial form, there are some of 
 those forms inanimate, some vegetative, 
 some animal, and some rational. The three 
 former kinds can only subsist in matter ; 
 but the last, according to the schoolmen, is 
 immediately created by God, and infused 
 into the body, making one substance with 
 it, while they are united; yet capable of 
 being disjoined from the body, and of sub- 
 sisting by itself. 
 
 Such are the principles of natural things in 
 the Peripatetic system. It retains so much 
 of the ancient Pythagorean doctrine, that 
 we cannot ascribe the invention of it solely 
 to Aristotle, although he, no doubt, made 
 considerable alterations in it. The first 
 matter was probably the same in both sys- 
 tems, and was in both held to be eternal. 
 They differed more about form. The Py- 
 thagoreans and Platonists held forms or 
 ideas, as they called them, to be eternal, 
 immutable, and self-existent. Aristotle 
 maintained that they were not eternal, nor 
 self-existent. On the other hand, he did 
 not allow them to be produced, but educed 
 from matter ; yet he held them not to be 
 actually in the matter from which they are 
 educed, but potentially only. But these 
 two systems differed less from one another, 
 than that of Des Cartes did from both. 
 
 In the world of Des Cartes we meet with 
 two kinds of beings only — to wit, body and 
 mind ; the first the object of our senses, 
 
 • It is not, however, to be supposed that the 
 scholastic doctrine of Substantial Forms receives any 
 countenance from the authority of Aristotle, if we 
 lav aside his language touching the soul. — H. 
 
 the other of consciousness ; both of thera 
 things of which we have a distinct appre- 
 hension, if the human mind be capable of 
 distinct apprehension at all. To the first, 
 no qualities are ascribed but extension, 
 figure, and motion ; to the last, nothing but 
 thought, and its various modifications, of 
 which we are conscious." He could ob- 
 serve no common attribute, no resembling 
 feature, in the attributes of body and mind, 
 and therefore concluded them to be distinct 
 substances, and totally of a different nature ; 
 and that body, from its very nature, is in- 
 animate and inert, incapable of any kind of 
 thought or sensation, or of producing any 
 change or alteration in itself. [133] 
 
 Des Cartes must be allowed the honour 
 of being the first who drew a distinct line 
 between the material and intellectual world, 
 which, in all the old systems, were so 
 blended together that it was impossible to 
 say where the one ends and the other be- 
 gins. -j- How much this distinction hath 
 contributed to the improvements of modern 
 times, in the philosophy both of body and 
 of mind, is not easy to say. 
 
 One obvious consequence of this distinc- 
 tion was, that accurate reflection on the 
 operations of our own mind is the only way 
 to make any progress in the knowledge of 
 it. Malebranche, Locke, Berkeley, and 
 Hume, were taught this lesson by Des 
 Cartes ; and to it we owe their most va- 
 luable discoveries in this branch of philo- 
 sophy. The analogical way of reasoning 
 concerning the powers of the mind from the 
 properties of body, which is the source of 
 almost all the errors on this subject, and 
 which is so natural to the bulk of mankind, 
 was as contrary to the principles of Des 
 Cartes, as it was agreeable to the princi- 
 ples of the old philosophy. We may there- 
 fore truly say, that, in that part of philoso- 
 phy which relates to the mind, Des Cartes 
 laid the foundation, and put us into that 
 tract which all wise men now acknowledge 
 to be the only one in which we can expect 
 success. 
 
 Witli regard to physics, or the philosophy 
 of body, if Des Cartes had not the merit of 
 leading men into the right tract, we must 
 allow him that of bringing them out of a 
 wrong one. The Peripatetics, by assigning 
 to every species of body a particular sub- 
 stantial form, which produces, in an un- 
 kno\vn manner, all the effects we observe 
 in it, put a stop to all improvement in this 
 branch of philosophy. Gravity and levity, 
 fluidity and hardness, heat and cold, were 
 qualities arising from the substantial form 
 of the bodies to which they belonged. Gen- 
 
 • In the Cartesian language, the term thought in. 
 eluded all of which we are conscious — H. 
 
 f This assertion is true in general ; but some in. 
 dividual exceptions might betaken. — H. 
 
 ,ri32, 133]
 
 (HAP. Via.] OF THE THEORY OF PERCEPTION, & 
 
 :c. 
 
 271 
 
 eration and corruption, substantial forms 
 and occult qualities, were always at hand, 
 to resolve every phfenomeuon. This phi- 
 losophy, therefore, instead of accounting 
 for any of the phaenomena of Nature, con- 
 trived only to give learned names to their 
 unknown causes, and fed men with the husks 
 of barbarous terms, instead of the fruit of 
 real knowledge. [ 1 34 ] 
 
 By the spreading of the Cartesian system, 
 materia prima, substantial forms, and oc- 
 cult qualities, with all the jargon of the 
 Aristotelian pliysics, fell into utter disgrace, 
 and were never mentioned by the followers 
 of the new system, but as a subject of ridi- 
 cule. Men became sensible that their un- 
 derstanding had been hoodwinked by those 
 hard terms. They were now accustomed 
 to explain the phtenomena of nature, by 
 the figure, size, and motion of the particles 
 of matter, things perfectly level to human 
 understanding, and could relish nothing in 
 philosophy that was dark and unintelligible. 
 Aristotle, after a reign of more than a 
 thousand years, was now exposed as an 
 object of derision even to the vulgar, arrayed 
 in the mock majesty of his substantial forms 
 and occult qualities. The ladies became 
 fond of a philosophy which waseasilylearned, 
 and required no words too harsh for their 
 delicate organs. Queens and princesses, 
 the most distinguished personages of the 
 age, courted the conversation of Des Cartes, 
 and became adepts in his philosophy. Wit- 
 ness Christina, Queen of Sweden, and 
 Elizabeth, daughter of Frederick, King of 
 Bohemia, the mother of our Royal Family. 
 The last, though very young when Des 
 Cartes wrote his " Principia," he declares 
 to be the only person he knew, who per- 
 fectly understood not only all his philoso- 
 phical writings, but the most abstruse of 
 his mathematical works. 
 
 That men should rush with violence from 
 one extreme, without going more or less 
 into the contrary extreme, is not to be ex- 
 pected from the weakness of human nature. 
 Des Cartes and liis followers were not ex- 
 empted from this weakness ; they thought 
 that extension, figure, and motion, were 
 sufficient to resolve all the phtenomena of 
 the material system. To admit other qua- 
 lities, whose cause is unknown, was to 
 return to Egypt, from which they had been 
 fio happily delivered. Ll-*-'^! 
 
 WJieii Sir Isaac Newton's doctrine of 
 gravitation was published, the great objec- 
 tion to it, which hindered its general recep- 
 tion in Euro])e for half a century, was, that 
 gravitation seemed to be an occult quality, 
 as it could not be accounted for by exten- 
 sion, figure, and motion, the known attri- 
 butes of liody. 'J'liey who delendeil him 
 found it diffi(!ult to answer tliis objection to 
 the satisfaction of tliose who iiad Itccn 
 [1.34-l.'}(il 
 
 initLited in the principles of the Cartesian 
 system. But, by degrees, men came to 
 be sensible that, in revolting from Ari- 
 stotle, the Cartesians had gone into the oppo- 
 site extreme ; experience convinced theni 
 that there are qualities in the material 
 world, whose existence is certain though 
 their cause be occult. To acknowledge this, 
 is only a candid confession of human ignor- 
 ance, than which there is nothing more be- 
 coming a philosophei*. 
 
 As all that we can know of the mind must 
 be derived from a careful observation of its 
 operations in ourselves ; so all that we can 
 know of the material system must be derived 
 from what can be discovered by our senses. 
 Des Cartes was not ignorant of this ; nor 
 was his system so unfriendly to observation 
 and experiment as the old system was.* 
 He made many experiments, and called 
 earnestly upon all lovers of truth to aidliini 
 in this way ; but, believing that all the 
 pluBuomena of the material world are the 
 result of extension, figure, and motion, and 
 that the Deity always combines these, so as 
 to produce the phenomena in the sinipk'st 
 manner possible, he thought that, from .a 
 few experiments, he might be able to dis- 
 cover the simplest way in which the obvious 
 pha'uomcna of nature can be produced by 
 matter and motion only ; and that this must 
 be the way in which they are actually pro- 
 duced. His conjectures were ingenious, upon 
 the principles he had adopted ; but they are 
 found to be so far from the truth, that they 
 ought for ever to discourage philosophers 
 from trusting to conjecture in the operations 
 of nature. L^-^^J] 
 
 The vortices or whirlpools of subtile 
 matter by which Des Cartes endeavoured 
 to account for the phienomena of the ma- 
 terial world, are now found to be fictions, 
 no less than the sensible species of Ari- 
 stotle. -f- 
 
 It was reserved for Sir Isaac Newton to 
 point out clearly the road to the knowledge 
 of nature's works. Taught by Lord Bacon 
 to despise liypothoses as the fictions of hu- 
 man fancy, he laid it down as a rule of 
 philosophising, that no causes of natural 
 things ought to be assigned but such as can 
 be proved to have a real existence. Jle 
 saw that all the length men can go in ac- 
 counting for pluunomena, is to discover the 
 laws of nature according to which they arc 
 produced; and, therefore, that the true 
 method of philoso])liising is this : From 
 real facts, ascertaineil by observation and 
 experiment, to collect by just induction tho 
 
 • 'J'hat is, the Ariitotclic. But Ari>tn(!e liimsclf 
 waR as (lerliin-(l ati advocate of cxpiTiniont n» any 
 pliilo8ii|iht'r ; and it is not to lie iinpnicd lo liini that 
 his aiilhrinly had Milin(|ni'Mily tho rllict of imiu'ii. 
 ii)((, by liiiriK held to «ii|icriic-(lc', ol scrvalion — II 
 
 t Head " tlic n'n-iblc ►i>Cfii'» of the »choolnu'ii ." 
 Sec Nolo M — II.
 
 272 
 
 ON THE INTELLECTUAL POWERS. 
 
 [^ESSAY 
 
 II. 
 
 laws of Nature, and to apply the laws so 
 discovered, to account for the phseuomena 
 of Nature. 
 
 Thus, the natural philosopher has the 
 rules of his art fixed with no less precision 
 than the mathematician, and may be no less 
 certain when he keeps within them, and 
 when he deviates from them. And, though 
 the evidence of a law of nature from induc- 
 tion is not demonstrative, it is the only kind 
 of evidence on which all the most import- 
 ant affairs of human life must rest. 
 
 Pursuinij this road without deviation, 
 Newton discovered the laws of our planet- 
 ary system, and of the rays of light ; and 
 gave the first and the noblest examples of 
 that chaste induction which Lord Bacon 
 could only delineate in theory. 
 
 How strange is it that the human mind 
 should have wandered for so many ages, 
 without falling into this tract ! How much 
 more strange, that, after it has been clearly 
 discovered, and a happy progress made in it, 
 many choose rather to wander in the fairy 
 regions of hypothesis ! [137] 
 
 To return to Des Cartes's notions of the 
 manner of our perceiving external objects, 
 from which a concern to do justice to the 
 merit of that great reformer in philosophy 
 has led me to digress, he took it for granted, 
 as the old philosophers had done, that what 
 we immediately perceive must be either in 
 the mind itself, or in the brain, to which 
 the mind is immediately present. The im- 
 pressions made upon our organs, nerves, 
 and brain could be nothing, according to 
 his philosophy, but various modifications of 
 extension, figure, and motion. There could 
 be nothing in the brain like sound or colour, 
 taste or smell, heat or cold ; these are sens- 
 ations in the mind, which, by the laws of 
 the union of soul and body, are raised on 
 occasion of certain traces in the brain ; and 
 although he gives the name of ideas to those 
 traces in the brain, he does not think it 
 necessary that they should be perfectly 
 like to the things which they represent, 
 any more than that words or signs should 
 resemble the things they signify. But, 
 says he, that we may follow tne received 
 opinion as far as is possible, we may allow 
 a slight resemblance. Thus we know that 
 a print in a book may represent houses, 
 tem])les, and groves ; and so far is it from 
 being necessary that the print should be 
 perfectly like the thing it represents, that 
 its perfection often requires the contrary : 
 for a circle must often be represented by an 
 ellipse, a square by a rhombus, and so of 
 other things. • 
 
 • But be it observed that Des Cartes did not allow, 
 far less hold, that the mind had any cognizance of 
 these organic motions — of these material ideas They 
 were merely the antecedents, established by the law of 
 union, of the mental idea; which mental idea was no- 
 
 The perceptions of sense, he thought, are 
 to be referred solely to the union of soul 
 and body. They commonly exhibit to us 
 only what may hurt or jirofit our bodies ; 
 and rarely, atid by accident only, exhibit 
 things as they are in themselves. It is by 
 observing this, that we must learn to throw 
 off" the prejudices of sense, and to attend 
 with our intellect to the ideas which are hy 
 nature implanted in it. By this means we 
 shall understand that the nature of matter 
 does not consist in tliose things that affect 
 our senses, such as colour, or smell, or taste ; 
 but only in this, that it is something ex- 
 tended in length, breadth, and depth. [138] 
 
 The writings of Des Cartes have, in ge- 
 neral, a remarkable degree of perspicuity ; 
 and he undoubtedly intended that, in this 
 particular, his philosophy should be a per- 
 feet contrast to that of Aristotle ; yet, in 
 what he has said, in different parts of his 
 writings, of our perceptions of external 
 objects, there seems to be some obscurity, 
 and even inconsistency ; whether owing to 
 his having had different opinions on the sub- 
 ject at different times, or to the difficulty he 
 found in it, I will not pretend to say. 
 
 There are two points, in particular, 
 wherein I cannot reconcile him to himself ; 
 the first, regarding the place of the ideas 
 or images of external objects, which are the 
 immediate objects of perception ; the second. 
 with regard to the veracity of our externai 
 senses. 
 
 As to the first, he sometimes places the 
 ideas of material objects in the brain, not 
 only when they are perceived, but when 
 they are remembered or imagined ; and 
 this has always been held to be the Car- 
 tesian doctrine;* yet he sometimes says, 
 that we are not to conceive the images or 
 traces in the brain to be perceived, as if 
 there were eyes in the brain ; these traces 
 are only occasions on which, by the laws of 
 the union of soul and body, ideas are ex- 
 cited in the mind ; and, therefore, it is not 
 necessary that there should be an exact 
 resemblance between the traces and the 
 things represented by them, any more than 
 that words or signs should be exactly like 
 the things signified by them.-f- 
 
 These two opinions, I think, cannot be 
 reconciled. For, if the images or traces in 
 the brain are perceived,^: they must be the 
 
 thing more than a modification of the mind itself — 
 H. 
 
 * But not in Rcid's exclusive sense of the word 
 Idea.— H. 
 
 t The non. negation, in this instance, of all re- 
 semblance between the material Ideas, or orRauic 
 motions in (he brain, and the external reality, is OTie 
 of the occasional instances of Di's Cartes's reticence of 
 his subordinate doctrines, in order to avoid all useless 
 tilting against prevalent opinions. Another is his 
 sometimes giving to these motions the name of Spe. 
 cies. — H. 
 
 X Which, in Des Cartes' doctrine, they are not.— H. 
 
 [137, 138]
 
 CHAP, viii.] OF THE THEORY OF PERCEPTION, &c. 
 
 273 
 
 objects of perception, and not the occasions 
 of it only. On the other liand, if they are 
 only the occasions of our perceiving, they 
 are not perceived at all. Des Cartes seems 
 to have hesitated between the two opinions, 
 or to have passed from the one to the 
 other." Mr Locke seems, in like manner, 
 to have wavered between the two ; some- 
 times representing the ideas of material 
 things as being in the brain, but more fre- 
 quently as in the mind itself -f- [li5!*] 
 Neither Des Cartes nor Mr Locke could, 
 consistently with themselves, attribute any 
 other qualities to images in the brain but 
 extension, figure, <and motion ; for as to 
 those qualities which Mr Locke distin- 
 guished by the name of secondary qualities, 
 both pliilosophers believed them not to be- 
 long to body at all,:{: and, therefore, could 
 not ascribe them to images in the brain. § 
 
 Sir Isaac Newton and Dr Samuel Clarke 
 uniformly speak of the species or images of 
 material things as being in that part of the 
 brain called the sensorium, and perceived 
 by the miud there present ; but the former 
 speaks of this point only incidentally, and 
 with his usual modesty, in the form of a 
 query. || IMalebranche is perfectly clear and 
 unambiguous in this matter. According to 
 his system, the images or traces in the 
 brain are not perceived at all — they are 
 only occasions upon which, by the laws of 
 Nature, certain sensations are felt by us, 
 and certain of the divine ideas discovered to 
 our minds. 
 
 The second point on which Des Cartes 
 seems to waver, is with regard to the credit 
 that is due to the testimony of our senses. 
 
 Sometimes, from the perfection of the 
 Deity, and his being no deceiver, he infers 
 that our senses and our other faculties can- 
 not be fallacious; and since we seem clearly 
 to perceive that the idea of matter comes 
 to us from things external, which it per- 
 fectly resembles, therefore we must con- 
 clude that there really exists something 
 extended in length, breadtli, and depth, 
 having all the properties which we clearly 
 perceive to belong to an extended thing. 
 
 At other times, we find Des Cartes and 
 his followers making frequent comi)laints. 
 
 • Des CartPB had only one o|)inion on the point 
 T he difficulty which perplexes Keid arose from his 
 want of a systematic compreliension of the Catte-ian 
 philosophy, and his being unaware tliaf, by Ideas, 
 Des Cartes designated two very dilterent things — viz , 
 the proximate boddy anttcedeiit, and the mental 
 consequent.— H. 
 
 + Locke's opinion, if he had a precise one on the 
 matter, it is impossible to ascertain. See Note O. — 
 H. 
 
 t See above, p. 205, note • — H. 
 
 5 Yet I.ocke cxpref«ly denies them to be modificn- 
 tionsof mind. See Note O. — 11. 
 
 II Heid is correct in all he here says of Newton ntid 
 Clarke; It in indeed virtually admitted by Clarke 
 himnclf, in his controverRy wiih I.eibiiitz. Compare 
 t*ibnitii Opera, II., p. 101, and p. lb.;.— II. 
 
 [ isy, 1 lUj 
 
 as all the ancient philosophers did, of the 
 foUacies of sense. He warns us to throw 
 off its prejudices, and to attend only with 
 our intellect, to the ideas implanted there. 
 By this means we may perceive, that the 
 nature of matter docs not consist in hard- 
 ness, colour, weight, or any of those things 
 that affect our senses, but in this only, that 
 it is something extended in length, breadth, 
 and depth. [140] The senses, he says, 
 are only relative to our present state ; they 
 exhibit things only as they tend to profit 
 or to hurt us, and rarely, and by accident 
 only, as they are in themselves.* 
 
 It was probably owing to an aversion to 
 admit anything into philosophy, of which 
 we have not a clear and distinct concep- 
 tion, that Des Cartes was led to deny that 
 there is any substance of matter distmctfrom 
 those qualities of it which we perceive. -f- 
 We say that matter is something extended, 
 figured, moveable. Extension, figure, mo- 
 bility, therefore, are not matter, but quali- 
 ties, belonging to this something, which 
 we call matter. Des Cartes could not 
 relish this obscure something, which is sup- 
 posed to be the subject or sii/istrntiim of 
 those qualities ; and, therefore, maintained 
 that extension is the very essence of mat- 
 ter. But, as we must ascribe extension to 
 space as well as to matter, he found him- 
 self under a necessity of holding that space 
 and matter are the same thing, and differ 
 only in our way of conceivin": them ; so 
 that, wherever there is space there is mat- 
 ter, and no void left in the universe. The 
 necessary consequence of this is, that the 
 material world has no bounds nor limits. 
 He did not, however, choo.se to call it in- 
 finite, but indefinite. 
 
 It was probably owing to the same cause 
 that Des Cartes made the essence of the 
 soul to consist in thought. He would not 
 allow it to be an unknown something tluit 
 has the power of thinking ; it cannot, there- 
 fore, be without thought ; and, as he con- 
 ceived that there can lie no thotight witli- 
 out ideas, the soul nnist have had ideas in 
 its first formiition, which, of consequence, 
 are innate.J 
 
 The sentiments of those wlio came after 
 Des Cartes, with regard to tlie nature of 
 body and mind, have been various. Many 
 have maintained that body is only a collec- 
 tion of qualities to which we give one 
 
 • Hut see " Principia," ^ 6fi, Mjq — II. 
 
 t .See Stewart's "Elements," 1., Note A; lioyer 
 Collard's rragment. VIII.- H. 
 
 t ■] he doctrine of Des Cartes, in relation to lunate 
 Idfiis, lias been very generally mitunil(r»t(H)d ; and 
 by no one mori' Ihim liy I.ncke. What it really 
 iimount<'d to, is clearly stated In Ins strictures on 
 the rrogram (W Itc(;iii«. .Iiisliie lias latterly been 
 (lone him, among 01 llc■r^, by Mr .'-tewart, in his" Din- 
 sertation," and hv M l.ariimiKiiicre, in Ins " Coiirs." 
 See also the olil controversy ol Ue Vries with Hiiell 
 on iliij point — II.
 
 274 
 
 ON THE INTELLECTUAL POWERS. 
 
 [essay 
 
 II. 
 
 name ; and that the notion of a subject of 
 inhesion, to which those qiiaUties belong, 
 is only a fiction of the mind.* [141] 
 Some have even maintained that the soul 
 is only a succession of related ideas, with- 
 out any subject of inhesion.-t" It appears, 
 by what has been said, how far these no- 
 tions are aUied to the Cartesian system. 
 
 The triumph of the Cartesian system 
 over that of Aristotle, is one of the most 
 remarkable revolutions in the history of phi- 
 losophy, and has led me to dwell longer 
 upon it than the present subject perhaps 
 required. The authority of Aristotle was 
 now no more. That reverence for hard 
 words and dark notions, by which men's 
 understanding had been strangled in early 
 years, was turned into contempt, and every- 
 thing euspected which was not clearly and 
 distinctly understood. This is the spirit of 
 the Cartesian philosophy, and is a more 
 important acquisition to mankind than any 
 of its particular tenets; and for exerting 
 this spirit so zealously, and spreading it so 
 successfully, Des Cartes deserves immortal 
 honour. 
 
 It is to be observed, however, that Des 
 Cartes rejected a part only of the ancient 
 theory, concerning the perception of ex- 
 ternal objects by the senses, and that he 
 adopted the other part. That theory may 
 be divided into two parts : The first, that 
 images, species, or forms of external objects, 
 come from the object, and enter by the 
 avenues of the senses to the mind ; the 
 second part is, That the external object 
 itself is not perceived, but only the species 
 or image of it in the mind. The first part 
 Des Cartes and his followers rejected, and 
 refuted by solid arguments ; but the second 
 part, neither he nor his followers have 
 thought of calling in question ; being per- 
 suaded that it is only a representative 
 image in the mind of the external object 
 that we perceive, and not the object itself. 
 And this image, which the Peripatetics 
 called a species, he calls an idea, changing 
 the name only, while he admits the thing. J 
 [142] 
 
 It seems strange that the great pams 
 which this philosopher took to throw off" the 
 prejudices of education, to dismiss all his 
 former opinions, and to assent to nothing, 
 till he found evidence that compelled his 
 assent, should not have led him to doubt of 
 this opinion of the ancient philosophy. It 
 is evidently a philosophical opinion ; for the 
 vulgar undoubtedly believe that it is the 
 
 » As Locke, (but he is not consistent.) I.aw, 
 Green, Watts, and others. See Cousin, " Cours de 
 Vhilosophie," lotne II., Legon xviii.— H. 
 
 t Hume— H 
 
 X Des Cartes and Reid coincide in doctrine, it 
 Reid holds that we know the extended and exter. 
 nal object only, by a conception or subjective modifi- 
 tion of the percipient mind. See Notes N and C. — H. 
 
 external object which we immediately per- 
 ceive, and not a representative image of it 
 only. It is for this reason that they look 
 upon it as perfect lunacy to call in question 
 the existence of external objects." 
 
 It seems to be admitted as a first prin- 
 ciple, by the learned and the unlearned, that 
 what is really perceived must exist, and that 
 to perceive what does not exist is impossible. 
 So far the unlearned man and the philoso- 
 pher agree. The unlearned man says — I 
 perceive the external object, and I perceive 
 it to exist. Nothing can be more absurd 
 than to doubt of it. The Peripatetic says — 
 What I perceive is the very identical form 
 of the object, which came immediately from 
 the object, and makes an impression upon 
 my mind, as a seal does upon wax ; and, 
 therefore, I can have no doubt of the ex- 
 istence of an object whose form I perceive. -j- 
 But what says the Cartesian ? I perceive 
 not, says he, the external object itself. So 
 far he agrees with the Peripatetic, and differs 
 from the unlearned man. But I perceive 
 an image, or form, or idea, in my own 
 mind, or in my brain. I am certain of the 
 existence of the idea, because I imme- 
 diately perceive it.-]- But how this idea is 
 formed, or what it represents, is not self- 
 evident ; and therefore I must find argu- 
 ments by which, from the existence of the 
 idea which I perceive, I can infer the ex- 
 istence of an external object which it re- 
 presents. 
 
 As I take this to be a just view of the 
 principles of the unlearned man, of the Peri- 
 patetic, and of the Cartesian, so I thmk 
 they all reason consequentially from their 
 several principles : that the Cartesian has 
 strong grounds to doubt of the existence of 
 external objects ; the Peripatetic very little 
 ground of doubt ; and the unlearned [143] 
 man none at all : and that the difi'erence of 
 their situation arises from this — that the un- 
 learned man has no hypothesis ; the Peri- 
 patetic leans upon an hypothesis ; and the 
 Cartesian upon one half of that hypothesis. 
 Des Cartes, according to the spirit of his 
 own philosophy, ought to have doubted of 
 both parts of the Peripatetic hypothesis, or to 
 have given his reasons why he adopted one 
 part, as well as why he rejected the other 
 
 » This is one of the passages which favour the 
 opinion that Reid did suppose the non-ego to be 
 known in itself as existing, and not only in and 
 through the ego ; tor mankind in general believe 
 that the extended reality, as perceived, is something 
 more than a mere internal representation by the 
 mind, suggested in consequence of the impression 
 made by an unknown something on the sen^e. See 
 Note C— H. 
 
 + The Peripatetic and the Cartesian held that the 
 'pecics or idea was an object of consciousness. If 
 Reid understood the language houses, he mu^t hold 
 that the external and extended reality is an object of 
 consciousness. But this does not quadrate wiih his 
 doctrine, that we only know extension and figure by 
 a suggested conception in the mind. See Note C. — H. 
 
 [141-113]
 
 CHAP. IX.] OF THE SENTIMENTS OF MR LOCKE. 
 
 275 
 
 part ; especially, since the unlearned, who 
 have the faculty of perceiving objects by 
 their senses Ln no less perfection than 
 philosophers, and should, therefore, know, 
 !vs well as they, what it is they perceive, 
 have been unanimous in this, that the 
 objects they perceive are not ideas in their 
 own minds, but things external. It might 
 have been expected that a philosopher who 
 was so cautious as not to take his own ex- 
 istence for granted without proof, would not 
 have taken it for granted without proof, 
 that everything he perceived was only ideas 
 in his own mind. 
 
 But, if Des Cartes made a rash step in 
 this, as I apprehend he did, he ought not 
 to bear the blame alone. His successors 
 have still continued in the same track, and, 
 after his example, have adopted one part of 
 the ancient theory — to wit, that the objects 
 we immediately perceive are ideas only. All 
 their svstems are built on this foundation. 
 
 CHAPTER IX. 
 
 OF THE SENTIMENTS OF MR LOCKE. 
 
 The reputation which Locke's " Essay on 
 Human Understanding" had at home from 
 the beginning, and which it has gradually 
 acquired abroad, is a sufficient testimony of 
 its merit. [144] There is, perhaps, no 
 book of the metaphysical kind that has been 
 so generally read by those who understand 
 the language, or that is more adapted to 
 teach men to think with precision,* and to 
 inspire them with that candour and love of 
 truth which is the genuine spirit of philo- 
 sophy. He gave, I believe, the first ex- 
 ample in the English language of writing 
 on such abstract subjects, with a remarkable 
 degree of simplicity and perspicuity ; and 
 in this lie has been happily imitated by 
 others that came after him. No author 
 hath more successfully pointed out the 
 danger of ambiguous words, and the im- 
 portance of having distinct and determin- 
 ate notions in judging and reasoning. His 
 observations on the various powers of the 
 human understanding, on the use and abuse 
 of words, and on the extent and limits of 
 human knowledge, are drawn from atten- 
 tive reflection on the operations of his own 
 mind, the true source of all real knowledge 
 on these subjects ; and shew an uncommon 
 degree of penetration and judgment. IJut 
 he needs no panegyric of mine, and I men- 
 tion these things/only that, when I have 
 occa.sion to difiV-r from liim, I may not bo 
 thought insensible of the merit of an author 
 whom I highly respect, and to whom I owe 
 
 my first lights in those studies, as well as 
 my attachment to them. 
 
 He sets out in his essay with a full con- 
 viction, common to him with other philo- 
 sophers, that ideas in the mind are the 
 objects of all our thoughts in every opera- 
 tion of the understanding. This leads him 
 to use the word ided* so very frequently, 
 beyond what was usual in the English 
 language, that he thought it necessary, in 
 his introduction, to make this apology : — 
 " It being that term,'' says he, " which, I 
 I think, serves best to stand for whatsoever 
 is the object of understanding when a man 
 thinks, I have used it to express whatever 
 is meant by phantasm, notion, species, or 
 whatever it is which the mind can be em- 
 ployed about in thinking ; and I could not 
 avoid frequently using it. I presume it 
 will be granted me, that there are such 
 ideas in men's minds ; every man is con- 
 scious of them in himself, and men's words 
 and actions will satisfy him that they are in 
 others." [145] 
 
 Speaking of the reality of our knowledge, 
 he says, " It is evident the mind knows not 
 things immediately, but only by the inter- 
 vention of the ideas it has of them. Our 
 knowledge, therefore, is real, only so far as 
 there is a conformity between our ideas and 
 the reality of things. But what shall be ) 
 here the criterion ? How shall the mind, ''^ 
 when it perceives nothing but its own ideas, 
 Imow that they agree with things them- 
 selves ? This, though it seems not to want 
 difficulty, yet, I think, there be two sorts 
 of ideas that we may be assured agree with 
 things." 
 
 We see that INIr Locke was aware, no 
 less than Des Cartes, that the doctrine o- 
 ideas made it necessary, and at the sanv ^ 
 time difficult, to prove the existence of > 
 material world without us ; because tha 
 mind, according to that doctrine, perceives 
 nothing but a world of ideas in itself. Not 
 only Des Cartes, but Malebranche, Arnaukl, 
 and Norris, had perceived this diificulty, 
 and attempted to remove it with little suc- 
 cess. Mr Locke attempts the same thing ; 
 but his arguments are feeble. He even 
 seems to be conscious of this ; for he con- 
 cludes his reasoning with this observation 
 — " That we have evidence sufficient to 
 direct us in attaining the good and avoiding 
 the evil, caused by external objects, and 
 that this is the important concern we have 
 in being made acquainted with them." This, 
 indeed, is saying no more than will l)o 
 granted by those who deny the existence of 
 a mati'riai world. 
 As tiiere is no material difference between 
 
 ♦ To praiic l>ocke for precision, ii rather 
 miicli — ll. 
 [14t, ivr,'] 
 
 too 
 
 • r,o<-kc niny be s.iid to Imvp flmf nafiiraliziV. •'" 
 wyrd in IJixlisli pliilos<)|>liiriil laiiKUiKi', ill it« Caitc- 
 ■i»li cxlcinioii. — tl. 
 
 t2
 
 276 
 
 ON THE INTELLECTUAL POWERS. 
 
 [essay II. 
 
 l4. 
 
 Locke and Des Cartes with regard to the 
 perceptioil of objects by the senses, there 
 is the less occasion, in tliis place, to take 
 notice of all their differences in other points- 
 They differed about the origin of our ideas. 
 Des Cartes thought some of them were 
 innate ; the other maintained that there 
 are no innate ideas, and that they are all 
 derived from two sources — to wit, sensalion 
 and reflection ; meaning, by sensation, the 
 operations of our exterilal senses ; and, by 
 reflection, that attention which we are 
 capable of giving to the operations of our 
 own minds. [146] 
 
 They differed with regard to the essence 
 both of matter and of mind : the British 
 philosopher holding that the real essence of 
 both is beyond the reach of human know- 
 ledge ; the other conceiving that the very 
 essence of mind consists in thought, and 
 that of matter in extension, by which he 
 made matter and space not to differ in reality, 
 and no part of space to be void of matter. 
 
 Mr Locke explained, more distinctly than 
 had been done before, the operations of the 
 mind in classing the various objects of 
 thought, and reducing them to genera and 
 species. He was the first, I think, who 
 distinguished in substances what he calls 
 the nominal essence — which is only the 
 notion we form of a genus or species, and 
 which we express by a definition — from the 
 real essence or internal constitution of the 
 thing, which makes it to be what it is.* 
 Without this distinction, the subtile dis- 
 putes which tortured the schoolmen for so 
 many ages, in the controversy between the 
 nominalists and realists, could never be 
 brought to an issue. He shews distinctly 
 how we form abstract and general notions, 
 and the use and necessity of them in rea- 
 soning. And as (according to the received 
 principles of philosophers) every notion of 
 our mind must have for its object an idea 
 in the mind itself, -j- he thinks that we form 
 abstract ideas by leaving out of the idea of 
 n individual everything wherein it differs 
 from other individuals of the same species 
 or genus ; and that this power of forming 
 abstract ideas, is that which chiefly dis- 
 tinguishes us from brute animals, in whom 
 he could see no evidence of any abstract 
 ideas. 
 
 Since the time of Des Cartes, philoso- 
 phers have differed much with regard to the 
 share they ascribe to the mind itself, in the 
 fabrication of those representative bemgs 
 called ideas, and the manner in which this 
 work is carried on. 
 
 * Locke has no originality in this respect. — H. 
 
 •t Notion is here used for the apprehension of the 
 idea, or representative reality, which Reid supposed 
 that all philosophers viewed as snmething more than 
 the mere act of knowledge, considered in relation to 
 what was, through it, known or represented.— H. 
 
 Of the authors I have met with, Dr 
 Robert Hook is the most explicit. He was 
 one of the most ingenious and active mem- 
 bers of the Royal Society of London at its 
 first institution ; and frequently read lec- 
 tures to the Society, which were published 
 among his posthumous works. [147] In his 
 " Lectures upon Light," § 1, he makes 
 ideas to be material substances ; and thinks 
 that the brain is furnished with a proper 
 kind of matter for fabricating the ideas of 
 each sense. The ideas of sight, he thinks, 
 are formed of a kind of matter resembling 
 the Bononian stone, or some kind of phos- 
 phorus ; that the ideas of sound are formed 
 of some matter resembluig the chords or 
 glasses which take a sound from the vibra- 
 tions of the air ; and so of the rest. 
 
 The soul, he thinks, may fabricate some 
 hundreds of those ideas in a day ; and that, 
 as they are formed, they are pushed farther 
 off from the centre of the brain where the 
 soul resides. By this means they make a con- 
 tinued chain of ideas, coyled up in the brain ; 
 the first end of which is farthest removed 
 from the centre or seat of the soul, and the 
 other end is always at the centre, being the 
 last idea formed, which is always present 
 the moment when considered ; and, there- 
 fore, according as there is a greater number 
 of ideas between the present sensation or 
 thought in the centre and any other, the 
 soul is apprehensive of a larger portion of 
 time interposed. 
 
 Mr Locke has not entered into so minute 
 a detaQ of this manufacture of ideas ; but he 
 ascribes to the mind a very considerable 
 hand in forming its own ideas. With re- 
 gard to our sensations, the mind is passive, 
 " they being produced in us, only by dif- 
 ferent degrees and modes of motion in our 
 animal spirits, variously agitated by ex- 
 ternal objects." These, however, cease to 
 be as soon as they cease to be perceived ; 
 but, by the faculties of memory and imagin- 
 ation, " the mind has an ability, when it 
 wills, to revive them again, and, as it were, 
 to paint them anew upon itself, though 
 some with more, some with less difficulty." 
 
 As to the ideas of reflection, he ascribes 
 them to no other cause but to that attention 
 which the mind is capable of giving to its 
 own operations. These, therefore, are 
 formedby the mind itself. [148] He ascribes 
 likewise to the mind the power of com- 
 pounding its simple ideas into complex ones 
 of various forms ; of repeating them, and 
 adding the repetitions together ; of dividing 
 and classing them ; of comparing them, 
 and, from that comparison, of forming the 
 ideas of their relation ; nay, of forming a 
 general idea of a specie's or genus, by taking 
 from the idea of an individual everything 
 by which it is distinguished from other in- 
 dividuals of the kind, till at last it becomes 
 
 [146-148]
 
 CHAP. IX.J 
 
 OF THE SENTIMENTS OF MR LOCKE. 
 
 277 
 
 an abstract general idea, common to all the 
 individuals of the kind. 
 
 These, I think, are the powers which Mr 
 Locke ascribes to the mind itself in the 
 fabrication of its ideas. Bishop Berkeley, 
 as we shall see afterwards, abridged them 
 considerably, and Mr Hume much more. 
 
 The ideas we have of the various quali- 
 ties of bodies are not all, as Mr Locke 
 thinks, of the same kind. Some of them 
 are images or resemblances of what is really 
 in the body ; others are not. There are 
 certain qualities inseparable from matter ; 
 such as extension, solidity, figure, mobility. 
 Our ideas of these are real resemblances of 
 the qualities in the body ; and these he 
 calls primary qualities. But colour, sound, 
 taste, smell, heat, and cold, he calls second- 
 ary qualities, and thinks that they are 
 only powers in bodies of producing cer- 
 tain sensations in us ; which sensations 
 have nothing resembling them, though they 
 are commonlj' thought to be exact resem- 
 blances of something in the body. " Thus," 
 says he, " the idea of heat or light, which 
 we receive, by our eye or touch, from the 
 sun, are commonly thought real qualities 
 existing in the sun, and something more 
 than mere powers in it." 
 
 The names of primary and secondary 
 qualities were, I believe, first used by Mr 
 Locke ; but the distinction which they ex- 
 press, was well understood by Des Cartes, 
 and is explained by him in his " Principia," 
 Part I., § 69, 70, 71. [149] 
 
 Although no author has more merit than 
 Mr Locke, in pointing out the ambiguity of 
 words, and resolving, by that means, many 
 knotty questions, which had tortured the 
 wits of the schoolmen, yet, I apprehend, 
 he has been soinetimes misled by the ambi- 
 guity of the word idea, which he uses so 
 often almost in every page of his essay. 
 
 In the explication given of this word, we 
 took notice of two meanings given to it — a 
 popular and a philosophical. In the popu- 
 lar meaning, to have an idea of anything, 
 signifies nothing more than to think of it. 
 
 Althougli the operations of the mind are 
 most properly and naturally, and indeed 
 most commonly in all vulgar languages, ex- 
 pressed by active verbs, there is another 
 way of expressing them, less common, but 
 equally well understood. To think of a 
 thing, and to have a thought of it ; to be- 
 lieve a thing, and to have a belief of it ; to 
 see a thing, and iiave a sight of it ; to con- 
 ceive a thing, and to have a conception, 
 notion, or idea of it — are phrases perfectly 
 synonymous. In these phrases, the thought 
 means nothing but tfje act of thinking ; the 
 belief, the act of believing ; and tlie con- 
 ception, notion, or idea, tlie act of conceiv- 
 ing. 'JV> have a clear and distinct idea is, 
 in tliis Ken.se, nothing elae but to conceive 
 ■"Uy, 1501 
 
 the thing clearly and distinctly. .When the 
 word idea is taken in this popular sense, 
 there can be no doubt of our having ideas in 
 our minds. To think without ide;\s would 
 be to think without thought, which is a 
 manifest contradiction." 
 
 But there is another meaning of the word 
 idea peculiar to philosophers, and grounded 
 upon a philosophical theory, which the vul- 
 gar never think of. Philosophers, ancient 
 and modern, have maintained that the 
 operations of the mind, like the tools of an 
 artificer, can only be employed upon objects 
 that are present in the mind, or in the 
 brain, where the mind is supposed to reside. 
 [150] Therefore, objects that are distant in 
 time or place must have a representative in 
 the mind, or in the brain — some image or 
 picture of them, which is the object that the 
 mind contemplates. This representative 
 image was, in the old philosophy, called a 
 species or phantasm. Since the time of 
 Des Cartes, it has more commonly been 
 called an idea ; and every thought is con- 
 ceived to have an idea of its object. As 
 this has been a common opinion among 
 philosophers, as far back as we can trace phi- 
 losophy, it is the less to be wondered at that 
 they should be apt to confound the opera- 
 tion of the mind in thinking with the idea 
 or object of thought, whicli is supposed to 
 be its inseparable concomitant.' 
 
 If we pay any regard to the common 
 sense of mankind, thought and the object 
 of thought are different things, and ought 
 to be distinguished. It is true, thought 
 cannot be without an object — for every 
 man who thinks must think of something ; 
 but the object he thinks of is one thing, his 
 thought of that object is another thing. 
 They are distinguished in all languages, even 
 by the \'ulgar ; and many things may be 
 affirmed of thought — that is, of the opera- 
 tion of the mind in thinking — which cannot, 
 without error, and even absurdity, be af- 
 firmed of the object of that operation." 
 
 From this, I think, it is evident that, if 
 the word idea, in a work where it occurs in 
 every paragraph, is used without any inti- 
 mation of the ambiguity of the word, some- 
 times to signify thought, or the operation 
 of the mind in thinking, sometimes to sig- 
 nify those internal objects of thought which 
 philosophers suppose, this must occasion 
 confusion in the thoughts both of the au- 
 thor and of the readers. I take this to be 
 the greatest blemish in the " Es.say on Hu- 
 man Understanding." I api>reliond this is 
 tlie true source of several paradoxical opin- 
 ions in that excellent work, which I sliall 
 have occasion to take notice of. 
 
 Hero it is very natural to su^k, Whether 
 it was Mr Locke's opinion, that ideas are 
 
 V 
 
 • See Nolo C— II.
 
 278 
 
 ON THE INTELLECTUAL POWERS. 
 
 [essay ii. 
 
 the only objects of thought ? or, Whether 
 it is not possible for men to think of things 
 which are not ideas in the mind ?* [151] 
 
 To this question it is not easy to give a 
 direct answer. On the one hand, he says 
 often, in distinct and studied expressions, 
 that the term idea stands for whatever is 
 the object of the understanding when a man 
 thinks, or whatever it is which the mind 
 can be employed about in thinking : that 
 the mind perceives nothing but its own 
 ideas : that all knowledge consists in the 
 perception of the agreement or disagree- 
 1/ ment of our ideas : that we can have no 
 knowledge farther than we have ideas. 
 These, and many other expressions of the 
 like import, evidently imply that every 
 object of thought must be an idea, and can 
 be nothing else. 
 
 On the other hand, I am persuaded that 
 Mr Locke would have acknowledged that 
 we may think of Alexander the Great, or 
 of the planet Jupiter, and of numberless 
 things which he would have owned are not 
 ideas in the mind, but objects which exist 
 independent of the mind that thinks of 
 them.-f- 
 
 How shall we reconcile the two parts of 
 this apparent contradiction ? All I am able 
 to say, upon Mr Locke's principles, to recon- 
 cile them, is this, That we cannot think of 
 Alexander, or of the planet Jupiter, unless 
 we have in our minds an idea — that is, an 
 image or picture of those objects. The 
 idea of Alexander is an image, or picture, 
 or representation of that hero in my mind ; 
 
 * It is to be remembered that Keid means, by 
 Ideas, representative entities different from the cog. 
 nitive modifications of the mind itself —H. 
 
 t On the confusion of this and the fouisubseouent 
 paragraphs, see Note C— Whatever is the immediate 
 object of thought, of that we are necessarily conscious. 
 But of Alexander, for example, as existing, we are 
 necessa'ily not conscious. Alexander, as existing, 
 cannot, therefore, possibly be an immediate object of 
 thought; consequently, if we can be said to think of 
 Alexander at all, we can only be said to think of him 
 mediately, in and through a representation of which 
 we are coiiscious ; and that representation is the ira. 
 mediate object of thought. It nr.akes no difference 
 whether this immediate object be viewed as a lertium 
 quid, distinct from the existing reality and from the 
 conscious mind; or whether as a mere modality of 
 the conscious mind itself — as tne mere act of thought 
 considered in its relation to something beyond the 
 sphere of consciousness. In neither case, can we be 
 said (be it in the imagination of a possible or the 
 reciUcction of a past existence) to know a thing as 
 existing— that is, immediately ; and, therefore, if in 
 these operations we be said to know aught out the 
 mind at all, we can only be said to know it me. 
 diately — in other words, as a mediate object. The 
 whole perplexity arises from the ambiguity of the 
 term object, that term being used both fortheexter. 
 nal reality of which we are here not conscious, and 
 cannot therefore know in itself, and for the mental 
 representation which we know in itself, but which is 
 known only as relativeto the other. Reid chaoses to 
 abolish the former signification, on the supposition 
 that it only applies to a representative entity differ. 
 ent from the act of thought, in this suppos.tioii, 
 however, he is wrong ; nor does he obtain an imme- 
 diate knowledge, even In perception, by merely deny. 
 W\ecrude hyjOthesis of representaiion — H. 
 
 and this idea is the immediate object of my 
 thought when I think of Alexander. That 
 this was Locke's opinion, and that it has 
 been generally the opinion of philosophers, 
 there can be no doubt. 
 
 But, instead of giving light to the ques- 
 tion proposed, it seems to involve it in 
 greater darkness. 
 
 When I think of Alexander, I am told 
 there is an image or idea of Alexander in 
 my mind, which is the immediate object of 
 this thought. The necessary consequence 
 of this seems to be, that there are two ob- 
 jects of this thought — the idea, which is in 
 the mind, and the person represented by that 
 idea ; the first, the immediate object of the 
 thought, the last, the object of the same 
 thought, but not the immediate object. 
 [162] This is a hard saying; for it makes 
 every thought of things external to have a 
 double object. Every man is conscious of 
 his thoughts, and yet, upon attentive reflec- 
 tion, he perceives no such duplicity in the 
 object he thinks about. Sometimes men 
 see objects double, but they always know 
 when they do so : and I know of no philo- 
 sopher who has expressly owned this dupli- 
 city in the object of thought, though it fol- 
 lows necessarily from maintaining that, in 
 the same thought, there is one object that 
 is immediate and in the mind itself, and 
 another object which is not immediate, and 
 which is not in the mind.* 
 
 Besides this, it seems very hard, or rather 
 impossible, to understand what is meant by 
 an object of thought that is not an imme- 
 diate object of thought, A body in motion 
 may move another that was at rest, by the 
 medium of a third body that is interposed. 
 This is easily understood ; but we are unable 
 to conceive any medium interposed between 
 a mind and the thought of that mind ; and, 
 to think of any object by a medium, seems 
 to be words without any meaning. There 
 is a sense in which a thing may be said to 
 be perceived by a medium. Thus any kind 
 of sign may be said to be the medium by 
 which I perceive or understand the thing 
 signified. The sign by custom, or compact, 
 or perhaps by nature, introduces the thought 
 of the thing signified. But here the thing 
 signified, when it is introduced to the 
 thought, is an object of thought no less 
 immediate than the sign was before. And 
 there are here two objects of thought, one 
 succeeding another, which we have shewn 
 is not the case with respect to an idea, and 
 the object it represents. 
 
 • 'I'hat is, if by object was meant the same thing, 
 when the term is applied to the external reality, 
 and to its mental representation. Even under the 
 Scholastic theory of repeesentation, it was generally 
 maintained that Wm^pecit's itself is not an object of 
 perception, but the external r ality through it ; a 
 mode of speaking justly reprihended by the acuter 
 schoolmen. But in this lespect Reid is equally to 
 blame. See Note C — H. 
 
 ri51 "521
 
 cuAP. IX.] OF THE SENTIMENTS OF MR LOCKE. 
 
 279 
 
 I apprehend, therefore, that, if philoso- 
 phers will maintain that ideas in the mind 
 ^ are the only immediate objects of thought, 
 they will be forced to grant that they are the 
 Bole objects of thought, and that it is im- 
 possible for men to think of anything else. 
 [153] Yet, surely, Mr Locke believed that 
 we can think of many things that are not 
 ideas in the mind ; but he seems not to have 
 perceived, that the maintainmg that ideas 
 in the mind are the only immediate objects 
 of thought, must necessarily draw this con- 
 sequence along with it. 
 
 The consequence, however, was seen by 
 Bishop Berkeley and Mr Hume, who rather 
 chose to admit the consequence than to give 
 up the principle from which it follows. 
 
 Perhaps it was unfortunate for Mr Locke 
 that he used the word idea so very fre- 
 'jueutly as to make it very difficult to give 
 the attention necessary to put it always to 
 the same meanuig. And it appears evident 
 that, in many places, he means nothing 
 more by it but the notion or conception we 
 have of any object of thought ; that is, the 
 act of the mind in conceiving it, and not the 
 object conceived.* 
 
 In explaining this word, he says tliat he 
 uses it for whatever is meant by phantasm, 
 notion, species. Here are three synonyraes 
 to the word idea. The first and last are 
 very proper to express the philosophical 
 meaning of the word, being terms of art in 
 the Peripatetic philosophy, and signifying 
 images of external things in the mind, 
 which, according to that philosophy, are 
 objects of thought. But the word notion is 
 a word in common language, whose meaning 
 agrees exactly with the popular meaning of 
 
 * When wecontemplafea triangle, we may consider 
 it eiiher as a complement of three i-ides or of tlirec 
 angles ; not that the three sides and the tliree angles 
 are possible except through each otiier, but because 
 we may in thought view the figure— ^ua triangle, 
 in re.ility one and indivisible— in difTerent reUitions. 
 Ill like manner, we may coniider a representative act 
 of knowledge in tworelaliotis— l^.as an act riprcscn- 
 tative of somelhiiig, and, i" as an act cognitive of 
 that represeniation, although, 111 truth, these arc both 
 only one indivisible encrjiy — the representation only 
 existing as known, the cognition being only possible in 
 a representation. 'Ihus ^e- '" ""•' imagination of 
 a Centaur — the Centaur represented is the Centaur 
 known, the Centaur known is the Centaur repre- 
 ienicd. It is one act under two relations— a relation 
 to the sulijcct ki owing — a relation to the object re. 
 presented. Kut to a cognitive act considered in these 
 •evcral relations we may give either diderent names, 
 or we may confound thcin under one, or we may do 
 both; and this is actually done j some words express, 
 ing only one relation, others both or either, and 
 others properly the one but abusively also the other. 
 Thus Iriea properly deiiolesaii act of thought con. 
 •idered in relation tn an external something beyond 
 the sphere of consciousness— a representation; but 
 »ofne philoiophem, as i.ocke, abuse it to comprehend 
 the thought also, viewed a« cognitive of this reiiresen- 
 tatioii. Again, pfrcr/jtiun, riolion, cimcrpliun, &c. 
 {concept IS, unfortunately, obsolete) coniprehcnd 
 both, or may be u>ed to denote eiiher of tlie rela- 
 tions; and it is only by the context that we can ever 
 vaguely discover in which application they are in- 
 tended, 'ihis is unfoilunate ; but so it ii— H. 
 
 [L53-15,5] 
 
 the word idea, but not with the pliilosophi- 
 cal. 
 
 When tliese two different meanings o< 
 the word idea are confounded in a studiei' 
 explication of it, there is little reason to 
 expect that they should be carefully dis- 
 tinguished in the frequent use of it. There 
 are many passages in the Essay m whidh, 
 to make them intelligible, the word idea 
 must be taken in one of those senses, and 
 many others in which it must be taken in 
 the other. It seems probable that the 
 author, not attending to this ambiguity of 
 the word, used it in the one sense or the 
 other, as the subject-matter required ; and 
 the far greater part of his readers have done 
 the same. [154] 
 
 There is a third sense, in wliich he uses 
 the word not unfrcquently, to signify objects 
 of thought that are not in th'e mind, but 
 external. Of this he seems to be sensible, 
 and somewhere makes an apology for it. 
 When he affirms, as he does in innumerable 
 places, that all human Imowledge consists 
 in the perception of the agreement or dis- 
 agreement of our ideas, it is impossible to 
 put a meaning upon this, consistent with 
 his principles, unless he means by ideas 
 every object of human thought, whether 
 mediate or immediate ; everything, in a 
 word, that can be signified by the subject, 
 or predicate of a proposition. 
 
 Thus, we see that the word idea has three 
 different meanings in the essay; and the 
 author seems to have used it sometimes in one, 
 sometimes in another, without being aware 
 of any change in the meaning. The reader 
 slides easily into the same fallacy, that 
 meaning occurring most readily to his mind 
 wliich gives the best sense to what he reads. 
 I have met with persons professhig no slight 
 acquaintance with the " Essay on Human 
 Understanding," who maintained that the 
 word idea, wherever it occurs, means 
 nothing more than tliought ; and tliat, 
 where he speaks of ideas as images in the 
 mind, and as objects of thought, he is not 
 to be understood as speaking properly, but 
 figuratively or analogically. And, indeed, 
 I aiiprohend that it would be no small 
 •advantage to many passages in the book, 
 if they could admit of this interprt'tation. 
 
 It is not the fault of this philo.'^dpher 
 alone to have given too little attentioH to 
 the distinction between the operations of 
 the mind and the objects of thost: ojicra- 
 tions. Although this distinction be raniiliar 
 to the vulgar, andiuiiiid in the structiirc of 
 all languages, philoso|ihcrH, when they speak 
 of ideas, often confound [155] the two to- 
 gether ; and their tlieory concerning ideas 
 has led them to do so ; for ideas, being 
 siippo.sed to be a shailowy kind of beings, 
 internipdiate between the thought and tlio 
 object of thought, sometiiiies Beeni to cca-
 
 280 
 
 ON THE INTELLECTUAL POWERS. 
 
 1_ESSAY 
 
 II 
 
 lesce with the thought, sometmies witli tlie 
 object of thought, iiiul sometimes to have a 
 distinct existence of their own. 
 
 Tlie same philosophical theory of ideas 
 has led philosophers to confound tlie differ- 
 ent operations of the understanding, and 
 to call them all by the name of perception.* 
 Mr Locke, though not free from this fault, 
 is not so often chargeable with it as some 
 who came after him. The vulgar give the 
 name of perception to that immediate know- 
 ledge of external objects which we have by 
 our external senses. + This is its proper 
 meaning in our language, though sometimes 
 it may be applied to other things metaphori- 
 cally or analogically.^: When I think of 
 anything that does not exist, as of the 
 republic of Oceana, I do not perceive it — I 
 only conceive or imagine it.§ When I 
 think of what happened to me yesterday, I 
 do not perceive but remember it.|| When 
 I am pained with the gout, it is not proper 
 to say I perceive the pain ; I feel it, or am 
 conscious of it : it is not an object of per- 
 ception, but of sensation and of conscious- 
 ness.^ So far, the vulgar distinguish very 
 properly the different operations of the 
 mind, and never confound the names of 
 things so different in their nature. But 
 the theory of ideas leads philosophers to 
 conceive all those operations to be of one 
 nature, and to give them one name. They 
 are all, according to that theory, the per- 
 ception of ideas in the mind. Perceiving, 
 remembering, imagining, being conscious, 
 are all perceiving ideas in the mind, and 
 are called perceptiuiis. Hence it is that 
 philosophers speak of the perceptions of 
 memory, and the perceptions of imagina- 
 
 • No more than by calling^ them all by the name 
 of Cugniiioiis, or Acts of Consciouness. There was 
 no reason, either from etymology or usage, whyper- 
 ccption should not signify the energy of immediately 
 ai>|)rehendinp, in general ; and until Reid limited the 
 word to our apprehension of an external world, it 
 was, in fact, employed by philosophers, as tanta- 
 mount to an act ot consciousness. We were in need 
 of a word to express our sensitive cognitions as dis- 
 tinct from our sensitive feelings, (for the terra sens. 
 ation involved both,) and, therefore, Reid's restric- 
 tion, though contrary to all precedent, miy be ad- 
 mitted ; but his criticism of (ther philosophers for 
 their employment of the term, in a wider meaning, 
 is wholly groundless. — H. 
 
 t Bui not exclusively.— H. 
 
 X This is not correct — H. 
 
 § And why ? Simply bccau.oe we do not, by such 
 an act, know, or apprehend such an object to exist ; 
 we merely represent it. But perception was only 
 used lor such an apprehension. We could say, how- 
 ever, that we perceived (as we could say that we were 
 conscious of) the republic of Oceana, as imagined 
 by us, after Harrii:{;ton. — H. 
 
 II And this, for the same reason. What is remem- 
 bered is not and can not be immediately known ; 
 nought but the present mental representaiion is so 
 known ; and this we could properly say that we 
 perceived. — H. 
 
 II Beciu'e the feeling of pain, though only possible 
 through consciousness, is not an act of knowledge. 
 Bi t it could be properly said, / perceive a feeling of 
 pain. At any rate, theexpres.sinn 1 perceive a pain, 
 ii IS correct as 1 am conscious of a /ain.—H. 
 
 tion. They make sensation to be a percep- 
 tion ; and everything we perceive by our 
 senses to be an idea of sensation. Some- 
 times they say that they are conscious of 
 the ideas in their own minds, sometimes 
 that they perceive them.* [ISG] 
 
 However improbable it may appear that 
 ])hilosophers wlio have taken pains to study 
 the operations of their own minds, should 
 express them less properly and less dis- 
 tinctly than the vulgar, it seems really to be 
 the case ; and the only account that can be 
 given of this strange phtenomenou, I take 
 to be this : that the vulgar seek no theory 
 to account for the operations of their minds ; 
 they know that they see, and hear, and re- 
 member, and imagine; and those who think 
 distinctly will express these operations dis- 
 tinctly, as their consciousness represents 
 them to the mind ; but philosophers think 
 they ought to Icnow not only that there are 
 such operations, but how they are per- 
 formed ; how they see, and hear, and re- 
 member, and imagine; and, having invented 
 a theory to explain these operations, by 
 ideas or images in the mind, they suit their 
 expressions to their theory ; and, as a false 
 comment throws a cloud upon the text, so 
 a false theory darkens the phsenomeua 
 which it attempts to explain. 
 
 We shall examine this theory afterwards. 
 Here I would only observe that, if it is not 
 true, it may be expected that it should lead 
 ingenious men who adopt it to confound the 
 operations of the mind with their objects, 
 and with one another, even where the com- 
 mon language of the unlearned clearly dis- 
 tinguishes them. One that trusts to a false 
 guide is in greater danger of being led 
 astray, than he who trusts his own eyes, 
 though he should be but indifferently ac- 
 quainted with the road. 
 
 CHAPTER X. 
 
 OF THE SENTIMENTS OF BISHOP BERKELEY. 
 
 George Berkeley, afterwards Bishop 
 of Cloyne, published his " New Theory of 
 Vision," in 1709; his "Treatise concern- 
 ing the Principles of Human Knowledge," in 
 1710 ; and his "Dialogues between Hylas 
 and Philonous," in 1713 ; being then a Fel- 
 low of Trinity College, Dublin. [157] He is 
 acknowledged universally to have great 
 merit, as an excellent writer, and a very 
 acute and clear reasoner on the most ab- 
 stract subjects, not to speak of his virtues 
 as a man, which were very conspicuous : 
 yet the doctrine chiefly held forth in the 
 treatises above mentioned, especially in the 
 
 • The connection of the wider signification of the 
 term perception, with the more complex theory of 
 representation, has no foundauon — ti. 
 
 [156, 157"!
 
 cuAP. X.] OF THE SEJ^TIMENTS OF BISHOP BERKELEY. 281 
 
 two last, has generally been thought so very 
 absurd, that few can be brought to think 
 that he either believed it himself, or that 
 he seriously meant to persuade others of its 
 truth. 
 
 He maintains, and thinks he has demon- 
 strated, by a variety of arguments, ground- 
 ed on principles of philosophy universally 
 received, that there is no such thing as 
 matter in the universe ; that i<un and moon, 
 earth and sea, our own bodies, and those of 
 our friends, are nothing but ideas in the 
 uiiuds of those who think of them, and that 
 they have no existence when they are not 
 the objects of thought ; that all that is in 
 the universe may be reduced to two cate- 
 gories — to wit, minds, and ideas in the 
 mind. 
 
 But, however absurd this doctrine might 
 appear to the unlearned, who consider the 
 existence of the objects of sense as the 
 most evident of all truths, and what no man 
 in his senses can doubt, the philosophers 
 who had been accustomed to consider ideas 
 as the immediate objects of all thought, had 
 no title to view this doctrine of Berkeley in 
 so imfavourable a light. 
 
 They were taught by Des Cartes, and by 
 all that came after him, that the existence 
 of the objects of sense is not self-evident, 
 but requires to be proved by arguments ; 
 and, although Des Cartes, and many others, 
 had laboured to find arguments for this 
 purpose, there did not appear to be that 
 force and clearness in them which might 
 have been expected in a matter of such im- 
 portance. Mr Norris had declared that, 
 after all the arguments that had been 
 offered, the existence of an external world 
 is only probable, but by no means certain. 
 [158] Malebranche thought it rested upon the 
 authority of revelation, and that the argu- 
 ments drawn from reason were not perfectly 
 conclusive. Others thought that the argu- 
 ment from revelation was a mere sophism, 
 because revelation comes to us by our 
 senses, and must rest upon their authority. 
 
 Thus we see that the now philosophy 
 had been making gradual approaches towards 
 Berkeley's opinion ; and, whatever others 
 might do, the philosophers had no title to 
 look upon it as absurd, or unworthy of a 
 fair examination. Severalauthors attempt- 
 ed to answer his arguments, but with little 
 success, and others acknowledged that they 
 could neither answer them nor assent to 
 them. It is proV)able the Bishop made but 
 few converts to his doctrine ; Imt it is cer- 
 tain he made some ; and tliat he himself 
 continued, to the end of hie life, firmly per- 
 suaded, not only of its truth,* but of its 
 
 ■ Berkeley's cniifiilence in hi» idealinn was, how- 
 ever, ni.thiiiK to I'lrlite'i. J'liis ;ihU(MO|i|jer, in one 
 of 111* coiitroversial treutincx, imprecates ev( rlastiiiii 
 •lamnatioii on hirn?cl( not only nhuiild he retract, Imt 
 
 ri.iH, ir>9 ': 
 
 great importance for the improvement of 
 human knowledge, and especially for the 
 defence of religion. Dial. Pref. " If the 
 principles which I here endeavour to pro- 
 pagate, are admitted for true, the conse- 
 quences which I think evidently flow from 
 thence are, that atheism and scepticism 
 will be utterly destroyed, many intricate 
 points made plain, great difficulties solved, 
 several useless parts of science retrenched, 
 speculation referred to practice, and men 
 reduced from paradoxes to common sense." 
 In the " Theory of Vision," he goes no 
 farther than to assert that the objects of 
 sight are nothing but ideas in the mind, 
 granting, or at least not denying, that there 
 is a tangible world, which is really external, 
 and which exists whether we perceive it or 
 not. Whetherthereasonof thiswas,that his 
 system had not, at that time, wholly opened 
 to his own mind, or whether he thought it 
 prudent to let it enter into the minds of his 
 readers by degrees, I cannot say. I think 
 he insinuates the last as the reason, in the 
 " Principles of Human Knowledge." [159] 
 The " Theory of Vision," however, taken 
 by itself, and without relation to the main 
 branch of his system, contains very important 
 discoveries, and marks of great genius. He 
 distinguishes more accurately than any that 
 went before him, between the immediate 
 objects of sight, and those of the other 
 senses which are early associated with them. 
 He shews that distance, of itself and imme- 
 diately, is not seen ; but that we learn to 
 judge of it by certain sensations and per- 
 ceptions which are connected with it. This 
 is a very important observation ; and, I 
 believe, was first made by this author." 
 It gives much new light to the operations 
 of our senses, and serves to account for 
 many phsenomena in optics, of which the 
 greatest adepts in that science had always 
 either given a false account, or acknow- 
 ledged that they could j^ive none at all. 
 
 We may observe, by the way, that the 
 ingenious author seems not to have attended 
 to a distinction by which his general asser- 
 tion ought to have been limited. It is true 
 that the distance of an object from the eye is 
 not immediately seen ; but there is a certain 
 kind of distance of one object from another 
 which we see immediately. The author 
 acknowledges that there is a visible exten- 
 sion, and visible figures, which are proper 
 objects of sight ; there must therefore be a 
 visible distance. Astronomers call it an- 
 gular distance ; and, although they measure 
 
 sliould he even waver in repard (o any one priii'.iplc 
 of his doctrine ; a doctrine, the speculative result of 
 whicli lelt him, as he < onCesses, without even a ce^ 
 taiiity oC his own existence. (See ahove, p. li/!), 
 note ♦.) It is Varro who speaks ol the crcdula 
 p/ii!()scip/ii> um niiliii : hut this is to he crediiloui 
 even in increilulity. — II. 
 
 • This last statement !• Inaccurnle. — II
 
 282 
 
 ON THE INTELLECTUAL POWDERS. 
 
 [^ESSAY H. 
 
 V 
 
 it by the angle, which is made by two lines 
 drawn from the eye to the two distant ob- 
 jects, yet it is immediately perceived by 
 Bight, even by those who never thought of 
 that angle. 
 
 He led the way in shewing how we learn 
 to perceive the distance of an object from 
 the eye, though this speculation was carried 
 farther by others who came after him. He 
 made the distinction between that extension 
 and figure which we perceive by sight only, 
 land that which we perceive by touch ; call- 
 ing the first, visible, the last, tangible ex- 
 tension and figure. He shewed, likewise, 
 that tangible extension, and not visible, is 
 the object of geometry, although mathema- 
 ticians commonly use visible diagrams in 
 their demonstrations.* [160] 
 
 The notion of extension and figure which 
 we get from sight only, and that which we 
 get from touch, have been so constantly 
 conjoined from our infancy in all the judg- 
 ments we form of the objects of sense, 
 that it required great abilities to distin- 
 guish them accurately, and to assign to 
 each sense what truly belongs to it ; " so 
 diflBeult a thing it is," as Berkeley justly 
 observes, " to dissolve an union so early 
 begun, and confirmed by so long a habit." 
 This point he has laboured, through the 
 whole of the essay on vision, with that 
 uncommon penetration and judgment which 
 he possessed, and with as great success as 
 could be expected in a first attempt upon 
 80 abstruse a subject. 
 
 He concludes this essay, by shewing, in 
 no less than seven sections, the notions 
 which an intelligent being, endowed with 
 sight, without the sense of touch, might 
 form of the objects of sense. This specu- 
 lation, to shallow thinkers, may appear to 
 be egregious trifling, f To Bishop Ber- 
 keley it appeared in another light, and will 
 do so to those who are capable of entering 
 into it, and who know the importance of it, 
 in solvmg many of the phtenomena of vision. 
 He seems, indeed, to have exerted more 
 force of genius in this than in the main 
 branch of his system. 
 
 In the new philosophy, the pillars by 
 which the existence of a material world was 
 supported, were so feeble that it did not 
 re mire the force of a Samson to bring them 
 
 • Properly speak np, it is neither tangible nor 
 visible extension which is the obj. ct of geometry, 
 but intelligible, pure, or a pri'or/'oxtcnsion — H. 
 
 f This, I have no doubt, s in allusion lo Priestley. 
 That writer had, not very courteously, said, in his 
 " Examination of Reiil"s Inquiry" '' I do not re- 
 member to ha»e seen a more egrrgious piece of so. 
 Itmn trifling than the chapter which our author calls 
 the' Geometry of Visible^,' and his acc"Unt of the 
 ' Idomenians,'ss he terms thi se imaginary liciiigs who 
 Had no ide^s ol suhitance but from sight." — In a note 
 upon that L-hapter of " Tli' Inquiry,'' I stated that 
 the thought of a Geometry of Visibles was original to 
 Berkeley, and I h.->d then no recollection of Reid'a 
 ■cknowledgnent in tlic present paragraph.— H. 
 
 down ; and in this we have not so much 
 reason to admire the strength of Berkeley's 
 genius, as his boldness in publishing to the 
 world an opinion which the unlearned would 
 be apt to interpret as the sign of a crazy 
 intellect. A man who was firmly persuaded 
 of the doctrine universally received by phi- 
 losophers concerning ideas, if he could but 
 take courage to call in question the exist- 
 ence of a material world, would easily find 
 unanswerable arguments in that doctrine. 
 [IGl] " Some truths there are," says Berke- 
 ley, " so near and obvious to the mind, that 
 a man need only open his eyes to see them. 
 Such," he adds, " I take this important one 
 to be, that all the choir of heaven, and fur- 
 niture of the earth — in a word, all those 
 bodies which compose the mighty frame 
 of the world — have not any subsistence 
 without a mind." Princ. § 6. 
 
 The principle from which this important 
 conclusion is obviously deduced, is laid down 
 in the first sentence of his principles of 
 knowledge, as evident ; and, indeed, it has 
 always been acknowledged by philosophers. 
 " It is evident," says he, " to any one who 
 takes a survey of the objects of human 
 knowledge, that they are either ideas ac- 
 tually imprinted on the senses, or else such 
 as are perceived, by attending to the pas- 
 sions and operations of the mind ; or, lastly, 
 ideas formed by help of memory and imagin- 
 ation, either compounding, dividing, or 
 barely representing those originally per- 
 ceived in the foresaid ways." 
 
 This is the foundation on which the whole 
 system rests. If this be true, then, indeed, 
 the existence of a material world must be 
 a dream that has imposed upon all mankind 
 from the beginning of the world. 
 
 The foundation on which such a fabric 
 rests ought to be very solid and well esta- 
 blished ; yet Berkeley says nothing more for 
 it than that it is evident. If he means that 
 it is self-evident, this indeed might be a 
 good reason for not offering any direct argu- 
 ment in proof of it. But I apprehend this 
 cannot justly be said. Self-evident propo- 
 sitions are those which appear evident to 
 every man of sound understanding who ap- 
 prehends the meaning of them distinctly, 
 and attends to them without prejudice. Can 
 this be said of this proposition. That all the 
 objects of our knowledge are ideas in our 
 own minds ?" I believe that, to any man 
 
 • To the Idealist, it is of perfect indifference whether 
 this proposition, in Keid's sense of the expression 
 Ideas, be admitted, or whether it be held that we are 
 conscious of nothing but of the modifications of our 
 own minds. For, on the supi'osition that we can 
 know the non-ego only in and through the ego, it 
 follows, (since we can know nothing immediately of 
 which we are not conscious, and it being allowed 
 that we are conscious only of mind,) that it is con. 
 tradiciory to suppiss aught, as known, {i.e., any ob- 
 ject of knowledge,) to be known otherwise than as u 
 phxnomenon ol mind. — H. 
 
 160, 161] 
 
 [1
 
 ;uAP. X.J OF THE SENTIMENTS OF BISHOP BERKELEY. 
 
 283 
 
 uninstructed in philosophy, this proposition 
 will appear very improloable, if not absurd. 
 [1C2] However scanty his knowledge may 
 be, he considers the sun and moon, the earth 
 and sea, as objects of it; and it will be difficult 
 to persuade him that those objects of his 
 knowledge are ideas in his own mind, and 
 have no existence when he does not think 
 of them. If I may presume to speak my 
 own sentiments, I once believed this doc- 
 trine of ideas so firmly as to embrace the 
 whole of Berkeley's system in consequence 
 of it ; till, finding other consequences to 
 follow from it, which gave me more unea- 
 siness than the want of a material world, 
 it came into my mind, more than forty 
 years ago, to put the question, AVhat e\'i- 
 dence have I for this doctrine, that all the 
 objects of my knowledge are ideas in my 
 own mind ? From that time to the pre- 
 sent I have been candidly and impartially, 
 as I think, seeking for the evidence of this 
 principle, but can find none, excepting the 
 authority of philosophers. 
 
 We shall have occasion to examine its 
 evidence afterwards. I would at present 
 only observe, that all the arguments brought 
 by Berkeley against the existence of a ma- 
 terial world are grounded upon it ; and that 
 he has not attempted to give any evidence 
 for it, but takes it for granted, as other 
 philosophers had done before him. 
 
 But, supposing this principle to be true, 
 Berkeley's system is impregnable. No 
 demonstration can be more evident than 
 his reasoning from it. Whatever is per- 
 ceived is an idea, and an idea can only 
 exist in a mind. It has no existence when 
 it is not perceived ; nor can there be any- 
 thing like an idea, but an idea. 
 
 So sensible he was that it required no 
 laborious reasoning to deduce his system 
 from the principle laid down, that he was 
 afraid of being thought needlessly prolix in 
 handling the subject, and makes an apology 
 for it. Princ. § 22. " To what purjjosc 
 is it," says he, " to dilate upon that wliich 
 may be demonstrated, witli the utmost e^•i- 
 dence, in a line or two, to any one who is 
 capable of the least reflection ?" [1G3] But, 
 though his demonstration might have been 
 comprehended in a line or two, he very pru- 
 dently tliought that an opinion which the 
 world would be apt to look upon as a mon- 
 ster of absurdity, would not Ije able to make 
 its way at once, even by the force of a n:ikeil 
 demonstration. He observes, justly. Dial. 
 2, " That, thf)ugh a demonstration be never 
 BO well grounded and fairly ])ro])osed, yet 
 if there is, withal, a strain of prejudice, or 
 a wrong bias on the understanding, can it 
 be expected to perceive cleacly, and adliero 
 firmly to the truth ? No ; there is need of 
 time and jmiiLS ; the attention nm.4t bo 
 %wakened and detained, by a frequent re- 
 
 petition of the same thing, placed often in 
 the same, often in different lights." 
 
 It was, therefore, necessary to dwell 
 upon it, and turn it on all sides, till it became 
 familiar ; to consider all its consequences, 
 and to obviate every prejudice and pre- 
 possession that might hinder its admittance. 
 It was even a matter of some difficulty to 
 fit it to common language, so far as to 
 enable men to speak and reason about it 
 intelligibly. Those who have entered se- 
 riously into Berkeley's system, have found, 
 after all the assistance which his writings 
 give, that time and practice are necessary 
 to acquire the habit of speaking and think- 
 ing distinctly upon it. 
 
 Berkeley foresaw the opposition that 
 would be made to his system, from two 
 diff'erent quarters : first, from the philos- 
 ophers ; and, secuuilly, from the vulgar, 
 who are led by the plain dictates of nature. 
 The first he had the courage to oppose 
 openly and avowedly ; the second, he 
 dreaded much more, and, therefore, takes 
 a great deal of pains, and, I think, uses 
 some art, to court into his party. This 
 is particularly observable in his " Dia- 
 logues." He sets out with a declaration, 
 Dial. 1, " That, of late, he had quitted 
 several of the sublime notions he had got 
 in the schools of the philosophers, for vul- 
 gar opinions," and assures Hylas, his fel- 
 low-dialogist, " That, since this revolt from 
 metaphysical notions to the plain dictates 
 of nature and common sense, he found his 
 understanding strangely enlightened ; so 
 that he could now easily comprehend a great 
 many things, which before were all mvs- 
 tery and riddle." [1G4] Pref. to Dial. " If 
 his principles are admitted for true, men 
 will be reduced from paradoxes to common 
 sense." At the same time, he acknowledges, 
 " That they carry with them a great opposi- 
 tion to the prejudices of philosophers, which 
 have so far prevailed against the common 
 sense and natural notions of mankind." 
 
 When Hylas objects to him, Dial. 3, 
 " You can never persuade me, Philonous, 
 that the denying of matter or corporeal 
 substance is not repugnant to the universal 
 sense of mankind" — he answers, " I wish 
 both our opinions were fairly stated, and 
 submitted to the judgment of men who had 
 plain conmion sense, without the prejudices 
 of a learned education. Let mc be repre- 
 sented as one who trusts his senses, who 
 thinks he knows the things he sees and 
 feels, and entertains no doubt of their ex- 
 istence If by material substance is meant 
 
 only sensible body, that which is seen and 
 felt, (and the unphilosophical part of the 
 world, I dare say, moan no more,) then I 
 am more certain of matter's existence than 
 you or any other |ibil()so]>hcr pretend to be. 
 If there l>o aiiytliing which makes tho
 
 284 
 
 ON THE INTELLECTUAL POWERS. 
 
 [essay 
 
 II. 
 
 generality of mankind averse from the 
 notions I espouse, it is a misapprehension 
 that I deny the reahty of sensible things : 
 but, as it is you who are guilty of that, and 
 not I, it follows, that, in truth, their aversion 
 is against youv notions, and not mine. I 
 am content to appeal to the common sense 
 of the world for the truth of my notion. I 
 am of a vulgar cast, simple enough to 
 believe my senses, and to leave things as I 
 find them. I cannot, for my life, help 
 thinking that snow is white and fire hot." 
 
 When Hylas is at last entirely converted, 
 he observes to Philonous, " After all, the 
 controversy about matter, in the striot 
 acceptation of it, lies altogether between 
 you and the philosophers, whose principles, 
 I acknowledge, are not near so natural, or 
 so agreeable to the common sense of man- 
 kind, and Holy Scripture, as yours." [1C5] 
 Philonous observes, in the end, " That he 
 does not pretend to be a setter up of new 
 notions ; his endeavours tend only to unite, 
 and to place in a clearer light, that truth 
 which was before shared between the vul- 
 gar and the philosophers ; the former being 
 of opinion, that those things they im- 
 mediately perceive are the real things ; and 
 the latter, that the things immediately 
 perceived, are ideas which exist only in the 
 mind ; which two things put together do, 
 in effect, constitute the substance of what 
 lie advances." And he concludes by ob- 
 serving, " That those principles which at 
 first view lead to scepticism, pursued to a 
 certain point, bring men back to common 
 sense." 
 
 These passages shew sufficiently the 
 author's concern to reconcile his system to 
 the plain dictates of nature and common 
 sense, while he expresses no concern to 
 reconcile it to the received doctrines of 
 philosophers. He is fond to take part with 
 the vulgar against the philosophers, and to 
 vindicate common sense against their inno- 
 vations. What pity is it that he did not 
 carry this suspicion of the doctrine of philo- 
 sophers so far as to doubt of that philoso- 
 phical tenet on which his whole system is 
 built — to wit, that the things immediately 
 perceived by the senses are ideas which 
 exist only in the mind ! 
 
 After all, it seems no easy matter to make 
 the vulgar opinion and that of Berkeley to 
 meet. And, to accomplish this, he seen;s 
 to me to draw each out of its line towards 
 the other, not without some straining. 
 
 The vulgar opinion he reduces to this, 
 that the very things which we perceive by 
 our senses do really exist. This he grants ;* 
 for these things, says he, are ideas in our 
 minds, or complexions of ideas, to which 
 
 * This is one of the passages that may be broiifjht 
 prove ihat Ucid did allow to the ego an ;rara'.'diate 
 aiid real knowledge of the non-ego. — H. 
 
 we give one name, and consider as one 
 thing ; these are the immediate objects of 
 sense, and these do really exist. As to the 
 notion that those things have an absolute 
 external existence, independent of being 
 perceived by any mind, he thinks [ 1(J6] that 
 this is no notion of the vulgar, but a refine- 
 ment of philosophers ; and that the notion of 
 material substance, as Si substratum, or sup- 
 port of that collection of sensible qualities 
 to which we give the name of an apple or a 
 melon, is likewise an invention of philoso- 
 phers, and is not found with the vulgar till 
 they are instructed by philosophers. The 
 substance not being an object of sense, the 
 vulgar never think of it ; or, if they are 
 taught the use of the word, they mean no 
 more by it but that collection of sensible 
 qualities which they, from finding them con- 
 jomed in nature, have been accustomed to 
 call by one name, and to consider as one 
 thing. . 
 
 Thus he draws the vulgar opinion near 
 to his own ; and, that he may meet it half 
 way, he acknowledges that material things 
 have a real existence out of the mind of 
 this or that person ; but the question, says 
 he, between the materialist and me, is. 
 Whether they have an absolute existence 
 distinct from their being perceived by God, 
 and exterior to all minds ? This, indeed, 
 he f^ays, some heathens and philosophers 
 have affirmed ; but whoever entertains no- 
 tions of the Deity, suitable to the Holy 
 Scripture, will be of another opinion. 
 
 But here an objection occurs, which it 
 required all his ingenuity to answer. It is 
 this : The ideas in my mind cannot be the 
 same with the ideas of any other mind ; 
 therefore, if the objects I perceive be only 
 ideas, it is impossible that the objects I per- 
 ceive can exist anywhere, when I do not 
 perceive them ; and it is impossible that 
 two or more minds can perceive the same 
 object. 
 
 To this Berlceley answers, that this ob- 
 jection presses no less the opinion of the 
 materiaUst philosopher than his. But the 
 difficulty is to make his opinion coincide 
 with the notions of the vulgar, who are 
 firmly persuaded that the very identical 
 objects which they perceive, continue to 
 exist when they do not perceive them ; and 
 who are no less firmly persuaded that, when 
 ten men look at the sun or the moon, they 
 all see the same individual object.* [107] 
 
 To reconcile this repugnancy, he observes, 
 Dial. 3_" That, if the term same be taken 
 in the vulgar acceptation, it is certain (and 
 not at all repugnant to the principles he 
 maintains) that different persons may per- 
 ceive the same thing ; or the same thing or 
 idea exist in different minds. Words are 
 
 S,c the last note. — il. 
 
 [165-167]
 
 CHAP. X.] OF THE SENTIMENTS OF BISHOP BERKELEY. 
 
 285 
 
 of arbitrary imposition ; and, since men are 
 used to apply the word same, where no dis- 
 tinction or variety is perceived, and he does 
 not pretend to alter their perceptions, it 
 follows that, as men have said before, 
 several saw the same thirig, so they may, 
 upon like occasions, still continue to use the 
 same phrase, without any deviation, either 
 from pnipriety of language, or the truth of 
 things ; but, if the term same be used in the 
 acceptation of philosophers, who pretend to 
 an abstracted notion of identity, then, 
 according to their sundry definitions of this 
 term, (for it is not yet agreed wherein that 
 philosophic identity consists,) it may or 
 may not be possible for divers persons to 
 perceive the same thing ; but whether phi- 
 losophers shall think fit to call a thing the 
 same or no is, I conceive, of small import- 
 ance. Men may dispute about identity and 
 diversity, without any real difference in 
 their thoughts and opuiions, abstracted from 
 names." 
 
 Upon the whole, I apprehend that Berk- 
 eley has carried this attempt to reconcile 
 his system to the vulgar opinion farther 
 than reason supports him ; and he was no 
 doubt tempted to do so, from a just appre- 
 hension that, in a controversy of this kind, 
 the common sense of mankind is the most 
 formidable antagonist. 
 
 Berkeley has employed much pains and 
 ingenuity to shew that his system, if re- 
 ceived and believed, would not be attended 
 with those bad consequences in the conduct 
 of life, which superficial thinkers may be apt 
 to impute to it. His system does not take 
 away or make any alteration upon our plea- 
 sures or our pains : our sensations, whether 
 agreeable or disagreable, are the;same upon 
 his system as upon any other. These are real 
 things, and the only things that interest us. 
 [ IGii] They are produced in us according to 
 certain laws of nature, by which our con- 
 duct will be directed in attaining the one, 
 and avoiding the other ; and it is of no 
 moment to us, whether they are produced 
 immediately by the operation of some power- 
 ful intelligent being upon our minds ; or 
 by the mediation of some inanimate being 
 which we call matter. 
 
 The evidence of an all-governmg mind, 
 so far from being weakened, seems to appear 
 even in a more striking liglit upon his 
 hypothesis, than upon the common one. 
 The powers which inanimate matter is sup- 
 posed to possess, have always been the 
 stronghold of atheists, to which they had 
 recourse in defence of their system. This 
 fortress of atheism nuist be most efiectually 
 overturned, if there is no such thing as 
 matter in the universe. In all tlii.s the 
 Bishop reasons justly and acutely. But 
 there is one uncomfortable consequence of 
 his Kvatem, which beseems not to have at- 
 flG8, 169] 
 
 tended to, and from which it will be found 
 difficult, if at all possible, to guard it. 
 
 The consequence I mean is this — that, 
 although it leaves us sufficient evidence of a 
 supreme intelligent mind, it seems to take 
 away all the evidence we have of other 
 intelligent beings like ourselves. "Wliat I 
 call a father, a brother, or a frieud, is only 
 a parcel of ideas in my own mmd ; and, being 
 ideas in my mind, they cannot possibly have 
 that relation to another mind which they have 
 to mine, any more than the pain felt by me 
 can be the uidividual pain felt by another. I 
 can find no principle in Berkeley's system, 
 which affords me even probable ground to 
 conclude that there are other intelligent 
 beings, like myself, in the relations of father, 
 brother, friend, or fellow-citizen. I am left 
 alone, as the only creature of God in the 
 universe, in that forlorn state of efjoisrn 
 into which it is said some of the disciples of 
 Des Cartes were brought by his philo- 
 sophy.* [1C9] 
 
 Of all the opinions that have ever been 
 advanced by philosophers, this of Bishop 
 Berkeley, that there is no material worki, 
 seems the strangest, and the most apt to 
 bring philosophy into ridicule with plain 
 men whoare guided by the dictates of nature 
 and common sense. And, it will not, I ap- 
 prehend, be improper to trace this progeny 
 of the doctrine of ideas from its origin, and 
 to observe its gradual progress, till it acquired 
 such strength that a pious and learned 
 bishop had the boldness to usher it into the 
 world, as demonstrable from the principles 
 of philosophy universally received, and as 
 an admirable expedient for the advance- 
 ment of knowledge and for the defence of 
 religion. 
 
 During the reign of the Peripatetic phi- 
 losophy, men were little disposed to doubt, 
 and much to dogmatize. The existence of 
 the objects of sense was held as a first prin- 
 ciple ; and the received doctrine was, that 
 the sensible species or idea is the very form 
 of the external object, just separated from 
 the matter of it, and sent into tlie mind that 
 perceives it ; so that we find no appearance 
 of scepticism about the existence of mat- 
 ter under that philosophy. -f- 
 
 Dcs Cartes taught men to doubt even of 
 those things that had been taken for first 
 principles. He rejected:!: the doctrine of 
 
 » In which the soul, like the unhappy nido — 
 ^— " eompcrquc relinqin 
 Solasibi, temper longain itiiomilata vUlclur 
 Ire viiiin." — H. 
 + 'Ihi is not the rase. It roiild easily be shewn 
 that, in tlie schools of the niidd'eaKcs, the argumenfi 
 in favour of Ideali-sm were fully undirstood ; and 
 they would certainly have obtidned numerous jiHrti. 
 sans, had it not leeii seen that such » pliilii>o|ihicjil 
 opinion involved a theological heresy touchiiig the 
 euchatist. This was even lecuHUircd by St Auruii> 
 tii.e— H , ,. 
 
 J Altermany of the Peripatetics themsclvci — H.
 
 286 
 
 ON THE INTELLECIUAL POWERS. 
 
 Lessay II. 
 
 species or ideas coming from objects ; but 
 still maintained that what we immediately 
 perceive, is not the external object, but an 
 idea or image of it in our mind. This led 
 some of his disciples into Egoism, and to dis- 
 believe the existence of every creature in the 
 universe but themselves and their own ideas. * 
 
 But Des Cartes himself — either from 
 dread of the censure of the church, which 
 he took great care not to provoke ; or to shun 
 the ridicule of the world, which might have 
 crushed his system at once, as it did that of 
 the Egoists ;* or, perhaps, from inward 
 conviction — was resolved to support the ex- 
 istence of matter. To do this consistently 
 with his principles, he found himself obliged 
 to have recourse to arguments that are far- 
 fetched, and not very cogent. Sometimes 
 he argues that our senses ai-e given us by 
 God, who is no deceiver ; and, therefore, 
 we ought to believe their testimony. [170] 
 But this argument is weak ; because, accord- 
 ing to his principles, our senses testify no 
 more but that we have certain ideas : and, 
 if we draw conclusions from this testimony, 
 which the premises will not support, we 
 deceive ourselves. To give more force to 
 this weak argument, he sometimes adds, 
 that we have by nature a strong propensity 
 to believe that there is an external world 
 corresponding to our ideas. "f 
 
 JVIalebranche thought that this strong 
 propensity is not a sufficient reason for be- 
 lieving the existence of matter ; and that it 
 is to be received as an article of faith, not 
 certainly discoverable by reason. He is 
 aware that faith comes by hearing ; and that 
 it may be said that prophets, apostles, and 
 miracles are only ideas in our minds. But 
 to this he answers, that, though these things 
 are only ideas, yet faith turns them into 
 realities ; and this answer, he hopes, will 
 satisfy those who are not too morose. 
 
 It may perhaps seem strange that Locke, 
 who wrote .so nmch about ideas, should not 
 see those consequences which Berkeley 
 thought so obviously deducible from that 
 doctrine. Air Locke surely was not willing 
 that the doctrine of ideas should be thought 
 to be loaded with such consequences. He 
 acknowledges that the existence of a mate- 
 rial world is not to be received as a first 
 principle— nor is it demonstrable ; but he 
 otters the best arguments for it he can ; and 
 supplies the weakness of his arguments by 
 this observation — that we have such evi- 
 
 ♦ See above, p. 269, note h ; and below, under p. 
 1S7.— H ' 
 
 I We are only by nature led to believe in the exist- 
 ence ot'rn outif world, because we are by nature led 
 to Relieve that we have an immodiate knowledge of 
 1' as existing. Now, Des Cartes -ndthe philosophers 
 itigeniral (is Rcid an exception?) hold that we are 
 deluded in the latter belief; and yet they argue, on 
 the authority of the former, that an external world 
 exi>ts — H. 
 
 dence as is sufficient to direct us in pur- 
 suing the good and avoiding the ill we may 
 receive from external things, beyond which 
 we have no concern. 
 
 There is, indeed, a single passage in 
 Locke's essay, which may lead one to con- 
 jecture that he had a glimpse of that sys- 
 tem which Berkeley afterwards advanced, 
 but thought proper to suppress it within his 
 own breast. [171] The passage is in Book 
 4, c. 10, where, having proved the existence 
 of an eternal intelligent mind, he comes 
 to answer those who conceive that matter 
 also must be eternal, because we cannot 
 conceive how it could be made out of 
 nothing ; and having observed that the 
 creation of mind requires no less power than 
 the creation of matter, he adds what fol- 
 lows : — " Nay, possibly, if we could eman- 
 cipate ourselves from vulgar notions, and 
 raise our thoughts, as far as they would 
 reach, to a closer contemplation of things, 
 we might be able to aim at some dim and 
 seeming conception, how matter might at 
 first be made and begin to exist, by the 
 power of that eternal first Being ; but to 
 give beginning and being to a spirit, would 
 be found a more inconceivable effect of om- 
 nipotent power. But this being what would 
 perhaps lead us too far from the notions on 
 which the philosophy now in the world is 
 built, it would not be pardonable to deviate 
 so far from them, or to inquire, so far as 
 grammar itself would authorize, if the com- 
 mon settled opinion opposes it ; especially 
 in this place, where the received doctrine 
 serves well enough to our present purpose.* 
 It appears from this passage — First, That 
 Mr Locke had some system in his mind, 
 perhaps not fully digested, to which we 
 might be led, by raising our thoughts to a 
 closer contemplation of things, and emanci- 
 pating them from vulgar notions ; Secondly, 
 That this system would lead so far from the 
 notions on which the philosophy now in the 
 world is built, that he thought proper to 
 keep it within his own breast ; Thirdly, 
 That it might be doubted whether this sys- 
 tem differed so far from the common settled 
 opinion in reality, as it seemed to do in 
 words ; Fourthly, By this system, we might 
 possibly be enabled to aim at some dim and 
 seeming conception how matter might at 
 first be made and begin to exist ; but it 
 would give no aid in conceiving how a 
 spirit might be made. These are the cha- 
 racteristics of that system which Mr Locke 
 had in his mind, and thought it prudent to 
 suppress. May they not lead to a probable 
 conjecture, that it was the same, or some- 
 thing similar to that of Bishop Berkeley ? 
 
 * Mr Stewart plausibly supposes that thi.s passage 
 contains rather an anticipation of Boscovich's Theory 
 of- Matter, than of Berke'ey's Theory of Idealism. 
 Philosophical Essas/s, p. 61. But see note F. — H. 
 
 fliO, 171]
 
 CHAP. X.J OF THE SENTIMENTS OF BISHOP BERKELEY. 
 
 287 
 
 According to Berkeley's system, God'screat- 
 ing the material world at sucli a time, means 
 no more but that he decreed from that time, 
 to produce ideas in the minds of finite spirits, 
 in that order and according to those rules 
 which we call the laws of Nature. [172] 
 This, indeed, removes all difficulty, in con- 
 ceiving how matter was created ; and 
 Berkeley does not faU to take notice of the 
 advantage of his system on that account. 
 But his system gives no aid in conceiving 
 how a spirit may be made. It appears, 
 therefore, that every particular Mr Locke 
 has hinted, with regard to that system which 
 he had in his mind, but thought it prudent 
 to suppress, tallies exactly with the system 
 of Berkelev. If we add to this, that 
 Berkeley's system follows from Mr Locke's, 
 by very obvious consequence, it seems rea- 
 sonable to conjecture, from the passage now 
 quoted, that he was not unaware of that 
 consequence, but left it to those who should 
 come after him to carry his principles their 
 full length, when they should by time be 
 better established, and able to bear the shock 
 of their opposition to vulgar notions. Mr 
 Norris, in his " Essay towards the Theory 
 of the Ideal or Intelligible World," pub- 
 lished in 1701, observes, that the material 
 world is not an object of sense ; because 
 sensation is within us, and has no object. 
 Its existence, therefore, he says, is a collec- 
 tion of reason, and not a very evident one. 
 
 From this detail we may learn that the 
 doctrine of ideas, as it was new-modelled 
 by Des Cartes, looked with an unfriendly 
 aspect upon the material world ; and, al- 
 though philosophers were very unwilling to 
 give up either, they found it a very difficult 
 task to reconcile them to each other. In 
 this state of things, Berkeley, I think, is 
 reputed the first who had the daring reso- 
 lution to give up the material world alto- 
 gether, as a sacrifice to the received phi- 
 losophy of ideas. 
 
 But we ought not, in this historical sketch, 
 to omit an author of far inferior name, 
 Arthur Collier, Rector of Langford Magna, 
 near Sarum. lie published a book in 17L5, 
 which he calls " Clavis Universalis ; or, a 
 New Inquiry after Truth ; being a demon- 
 stration of the non-existence or impossibility 
 of an external world." His arguments arc the 
 same in substance with Berkeley's; and he 
 appears to understand the whole strength of 
 his cause. [IT.i] Though ho is not deficient 
 in metaphysical acuteness, his style is dis- 
 agreeable, being full of conceits, of new- 
 coined words, scholastic terms, and per- 
 plexed sentences. He appears to be well 
 acquainted with Des Cartes, Malebranclie, 
 and Norris, as well as with Aristotle and 
 the schoolmen. But, what is very strange, 
 it docs not ayipear that he had ever heard 
 of Locke's Essay, which hail been j)ub- 
 [172-174] 
 
 lished twenty-four years, or of Berkeley's 
 " Principles of Knowledge," which had 
 been published three years. 
 
 He says he had been ten years firmly 
 convinced of the non-existence of an ex- 
 ternal world, before he ventured to publish 
 his book. He is far from thinking, as Ber- 
 keley does, that the vulgar are of his opi- 
 nion. If his book should make any con- 
 verts to his system, (of which he expresses 
 little hope, though he has supported it by 
 nine demonstrations,) he takes pains to 
 shew that his disciples, notwithstanding 
 their opinion, may, with the unenlightened, 
 speak of material things in the common 
 style. He himself had scruples of con- 
 science about this for some time ; and, if 
 he had not got over them, he must have 
 shut his lips for ever ; but he considered 
 that God himself has used this style in 
 speaking to men in the Holy Scripture, and 
 has thereby sanctified it to all the faithful ; 
 and that to the pure all things are pure. 
 He thinks his opinion may be of great 
 use, especially in religion ; and applies it, 
 in particular, to put an end to the con- 
 troversy about Christ's presence in the 
 sacrament. 
 
 I have taken the liberty to give this 
 short account of Collier's book, because I 
 believe it is rare, and little known. I have 
 only seen one copy of it, which is in the 
 University library of Glasgow.* [174] 
 
 CHAPTER XI 
 BISHOP Berkeley's sentiments of the 
 
 NATURE OF IDEAS. 
 
 I PASS over the sentiments of Bishop 
 Berkeley, with respect to abstract ideas, 
 and with respect to space and time, as 
 things which may more properly be consi- 
 dered in another place. But I must take 
 notice of one part of his system, wherein he 
 
 • This work, thougli of extreme rarity, and long 
 absolutely unknown to (he philosophers ot Ihiscoun. 
 try, had excited, troin the first, the attention of the 
 rieriiiaii raeta|)liysicians. A long analysis ot it was 
 given III the " Aeta Eruditorum ; " it is found quitcd 
 hy Uilfingcr, and other Lcbnitzians; and was sub. 
 sequently translaleil into (icrman, with coiitrover. 
 sial notes by Professor Kschenbach of l.'ostoek, in his 
 " Colleetioii of the principal writers who deny tlie 
 Healityof theirown Hody and of the whole Corporeal 
 World," nSfi. 'I he late learned Or I'arr had long 
 the uiteiition of publishing the woik 01 (.(jlhcr along 
 with some other rare U'.etaphysical treat ses. He did 
 not, however, aeenniplish his purpose; Vvhich in. 
 volved, likewi-e, an introductorydis(]iiisiti'in by him. 
 self; but a coinjilete impression ot the" ('lavi^ Univer. 
 Kalis" and four other tracts, was found, alter his 
 death ; : ml this having been purchased hy iMi l.uiii- 
 ley, tiHS by him, been recently publisliKl, under the 
 fille— " Mitaphysieal 1 raits, bv English I'liilnso. 
 pliers of the Kighteenth (eiilury," \c. I.ondon : 
 I8:)7. A very small eilition of the " Clavis" had been 
 printed in Kdinbur b, by priviite subscription, in lh» 
 previous year. \ Life of Collier liai likewise i" 
 ceiitly ap|iearcd — II.
 
 288 
 
 ON THE INTELLECTUAL POWERS. 
 
 [kssay 
 
 II. 
 
 seema to have deviated from the eomnion 
 opinion about ideas. 
 
 Tlu>uf;h he sets out in his principles of 
 knowledge, by telling us that it is evident 
 the objects of human knowledge are ideas, 
 and builds his whole system upon this prin- 
 ciple ; yet, in the progress of it, he finds 
 that there arc certain objects of human 
 knowledge that are not ideas, but things 
 which have a permanent existence. The 
 objects of knowledge, of which we have no 
 ideas, are our own minds, and their various 
 operations, other finite minds, and the 
 Supreme Mind. The reason why there 
 can be no ideas of spirits and their opera- 
 tions, the author informs us is this, That 
 ideas are jiassive, inert, unthinking beings ;* 
 they cannot, therefore, be the image or 
 likeness of things that have thought, and 
 will, and active power ; we have notions of 
 minds, and of their operations, but not 
 ideas. We know what we mean by think- 
 ing, willing, and perceiving ; we can rea- 
 son about beings endowed with those 
 powers, but we have no ideas of them. A 
 spirit or mind is the only substance or 
 support wherein the unthinking beings or 
 ideas can exist ; but that this substance 
 which supports or perceives ideas, should 
 itself be an idea, or like an idea, is evidently 
 absurd. 
 
 He observes, farther, Princip. sect. 142, 
 that " all relations, including an act of the 
 mind, we cannot properly be said to have 
 an idea, but rather a notion of the relations 
 or habitudes between things. [175] But 
 if, in the modern way, the word idea is 
 extended to spirits, and relations, and acts, 
 this is, after all, an affair of verbal con- 
 cern ; yet it conduces to clearness and pro- 
 priety, that we distinguish things very dif- 
 ferent by different names." 
 
 This is an important part of Berkeley's 
 system, and deserves attention. We are 
 led by it to divide the objects of human 
 knowledge into two kinds. The first is ideas, 
 which we have by our five senses ; they 
 have no existence when they are not per- 
 ceived, and exist only in the minds of those 
 who perceive them. The second kind of 
 objects comprehends spirits, their acts, and 
 the relations and habitudes of things. Of 
 these we have notions, but no ideas. No 
 idea can represent them, or have any simi- 
 litude to them : yet we understand what 
 they mean, and we can speak with under- 
 standing, and reason about them, without 
 ideas. 
 
 This account of ideas is very different 
 from that which Locke has given. In his 
 system, we have no knowledge where we 
 have no ideas. Every thought must have 
 
 • Herkeley is one of tlie philosophers who rea'ly 
 htld the tloclrine of ideas, erroneously, by Reid, at- 
 tiibuteU to all.— H. 
 
 an idea for its immediate object. In Ber- 
 keley's, the most important objects are 
 known without ideas. In Locke's system, 
 there are two sources of our ideas, sen.sa- 
 tion and reflection. In Berkeley's, sensa- 
 tion is the only source, because of the objects 
 of reflection there can be no ideas. We 
 know them without ideas. Locke divides 
 our ideas into those of substances, modes, 
 and relations. In Berkeley's system, there 
 are no ideas of substances, or of relations ; 
 but notions only. And even in the class of 
 modes, the operations of our own minds 
 are things of which we have distinct notions ; 
 but no ideas. 
 
 We ought to do the justice to Malebranche 
 to acknowledge that, in this point, as well 
 as in many others, his system comes nearer 
 to Berkeley's than the latter seems willing 
 to own. That author tells us that there 
 are four different ways in which we come 
 to the knowledge of things. To know things 
 by their ideas, is only one of the four. [176] 
 He affirms that we have no idea of our 
 own mind, or any of its modifications : that 
 we know these things by consciousness, 
 without ideas. Whether these two acute 
 philosophers foresaw the consequences that 
 may be drawn from the system of ideas, 
 taken in its full extent, and w^hich were after- 
 wards drawn by Mr Hume, I cannot pre- 
 tend to say. If they did, their regard to 
 religion was too great to permit them to ad- 
 mit those consequences, or the principles 
 with which they were necessarily connected. 
 
 However tliis may be, if there be so many 
 things that may be apprehended and known 
 without ideas, this very naturally suggests 
 a scruple with regard to those that are left : 
 for it may be said. If we can apprehend 
 and reason about the world of spirits, with- 
 out ideas. Is it not possible that we may 
 apprehend and reason about a material 
 world, without ideas ? If consciousness 
 and reflection furnish us with notions of 
 spirits and of their attributes, without idea-s, 
 may not our senses furnish us with notions 
 of bodies and their attributes, without ideas ? 
 
 Berkeley foresaw this objection to his 
 system, and puts it in the mouth of Hylas, 
 in the following words : — Dial. 3, Hylas. 
 " If you can conceive the mind of God, 
 without having an idea of it, why may not 
 I be allowed to conceive the existence of 
 matter, notwithstanding that I have no idea 
 of it ?" The answer of Philonous is — 
 " You neither perceive matter objectively, 
 as you do an inactive being or idea, nor 
 know it, as you do yourself, by a reflex act, 
 neither do you immediately apprehend it by 
 similitude of the one or the other, nor yet 
 collect it by reasoning from that which you 
 know immediately ; all which makes the 
 case of matter widely different from that of 
 the Deity." 
 
 ri75. 176"!
 
 cuAP. XI.] BISHOP BEUKELEYS SENTIMENTS OF IDEAS. 
 
 280 
 
 Though Hylas declares himself satisfied 
 with this answer, I confess I am not : be- 
 cause, if I may trust the faculties that God 
 has given me, I do perceive matter objec- 
 tively — that is, something which is extended 
 and solid, which may be measured an<l 
 weighed, is the immediate object of my touch 
 audsight.' [177] And this object I take to 
 be matter, and not an idea. And, though I 
 have been taught by philosophers, that what 
 I immediately touch is an idea, and not 
 matter ; yet I have never been able to dis- 
 cover this by the most accurate attention 
 to my own perceptions. 
 
 It were to be wished that this ingenious 
 author had explained what he means by 
 ideas, as distinguished from notions. The 
 word notion, being a word in common lan- 
 guage, is well understood. All men mean 
 by it, the conception, the apprehension, or 
 thought which we have of any object of 
 thought. A notion, therefore, is an act 
 of the mind conceiving or thinking of some 
 object. The object of thought may be 
 either something that is in the mind, or 
 something that is not in the mind. It may 
 be something that has no existence, or 
 something that did, or does, or shall exist. 
 But the notion which I have of that ob- 
 ject, is an act of my mind which really 
 exists while I think of the object ; but has 
 no existence when I do not think of it. 
 The word idea, in popular language, has 
 precisely the same meaning as the word 
 notion. Bat philosophers haA'e another 
 meaning to the word idea ; and what that 
 meaning is, I think, is very difficult to say. 
 
 The whole of Bishop Berkeley's system 
 depends upon the distinction between no- 
 tions and ideas ; and, therefore, it is worth 
 while to find, if we are able, what those 
 things are which he calls ideas, as distin- 
 guished from notions. 
 
 For this purpose, we may observe, that 
 he takes notice of two kinds of ideas — the 
 ideas of sense, and the ideas of imagina- 
 tion. " The ideas imprinted on the senses 
 by the Author of Nature," he says, " are 
 called real things; and those excited in the 
 imagination, being less regular, vivid, and 
 constant, arc more properly termed ideas, 
 or images of things, which they copy and 
 represent. [178] But tjien our sensations, 
 be they never so vivid and distinct, are 
 nevertheless ideas ; that is, they exist in 
 the mind, or are perceived by it as truly 
 a.s the ideas of its own framing. The ideas 
 of sense are allowed to have more reality 
 in them — that is, to be more strong, or- 
 derly, and coherent — than tiie creatures of 
 
 • Doe* Iltid mean losurrenHor his ddctrinc, h^it 
 percc|)tioti in a conception— that exKiision anil figure 
 arc not known by ocnsc, liut are notions siiK«eKtt'(loii 
 theofci^ion of pcnuation 'i II he docit not, liis Ian- 
 guagu in the text isiiiacruralc. — H. 
 
 I 177-17<)] 
 
 the nund. They are also less dependent 
 on the spirit, or thinking substance which 
 perceives them, in that tliey are excited by 
 the will of another and more powerful 
 si)irit ; yet still they are ideas ; and cer- 
 tainly no idea, whether faint or strong, can 
 exist, otherwise than in a mind perceiving 
 it." Principles, § 33. 
 
 From this passage we see that, liy tho 
 ideas of sense, the author means sensa- 
 tions;* and this, indeed, is evident from 
 many other passages, of which I shall men- 
 tion a few Principles, § 5. " Light and 
 
 colours, heat andcold, extension and figure — 
 in a word, the things we see and feel — what 
 are they but so many sensations, notions, 
 ideas, or impressions on the sense ? — and is 
 it possible to separate, even in thought, 
 any of these from perception ? For my 
 part, I might as easily divide a thing from 
 itself." § 18. "As for our senses, by 
 them we have the knowledge only of our 
 sensations, ideas, or those things that are 
 immediately perceived by sense, call them 
 what you will ; — but tlicy do not inform us 
 that things exist without the mind, or un- 
 perceived, like to those which are per- 
 ceived." § 25. " All our ideas, sensa- 
 tions, or the things which we perceive, by 
 whatever names they may be distinguished, 
 are visibly inactive ; there is nothing of 
 power or agency included in them." 
 
 This, tlierefore, appears certain — that, 
 by the ideas of sense, the author meant the 
 sensations we have by means of our senses. 
 I have endeavoured to explain the meaning 
 of tho word sensation, Essay I., chap. 1, 
 [p. 229,] and refer to the explicatit n there 
 given of it, w hich appears to me to be per- 
 fectly agreeable to the sense in which Bishop 
 Berkeley uses it.* 
 
 As there can be no notion or thought 
 but in a thinking being ; so there can be 
 no sensation but in a sentient being. [179] 
 It is the act or feeling of a sentient being ; 
 its very essence consists in its being felt. 
 Nothing can resemble a sensation, but a 
 similar sensation in the same or in some 
 other min<l. To think that any quality in 
 a thing that is inanimate can resemble a 
 sensation, is a great absurdity. In all this, 
 I cannot but agree perfectly with ]3isliop 
 Berkeley ; and 1 think his notions of seusa- 
 
 • How it can lie. asserted that by iikn.t of sense 
 Berkeley meant only what lieid did by sciisciiiiiti.i, 
 I cannot (:oni|irehend. lluit the former used iilMJi 
 of uiuc am) si-nsiillmis as converlilile exiiressions, is 
 true. Hut then iierkeley'-s ft/iA-i/^c/i was equivalent 
 to Rcid's si'tisalion plus Insjin-triitioii. 'I'his is mam. 
 fesl even by the passages adihiced in the text. In 
 that from !j v. of the " l'rinci|>les," Herkcley ex- 
 pressly calls extcnsiim and Jhjiiir sensations. Hut 
 it is a fundamental principle of HeidV philosophy, 
 not onlv thai neither exlensi n nur linure, l)ut that 
 none of the prini.iry qualities, aic sensations. I" 
 make a finnlc quotation— "M'heyic/jiian/ qualities," 
 he says, " are. mitlier sensiUiims, nor are they the 
 retcmblanccs of sensations."— /'l/id, p y:is. — II.
 
 290 
 
 ON THE INTELLECTUAL POWERS. 
 
 [_ESSAY II. 
 
 tion much more distinct and accurate than 
 Locke's, who thought that the primary 
 quahties of body are resemblances of our 
 sensations,* but that the secondary are not, 
 Tliat we have many sensations by means 
 of our external senses, there can be no 
 doubt ; and, if he is pleased to call those 
 ideas, there ought to be no dispute about 
 the meaning of a word. But, says Bishop 
 Berkeley, by our senses, we have the know- 
 ledge .only of our sensations or ideas, call 
 them which you will. I allow him to call 
 them which he will ; but I would have the 
 wordoratyin this sentence to be well weighed, 
 because a great deal depends upon it. 
 
 For, if it be true that, by our senses, we 
 have the knowledge of our sensations only, 
 then his system must be admitted, and the 
 existence of a material world must be given 
 up as a dream. No demonstration can be 
 more invincible than this. If we have any 
 knowledge of a material world, it must be 
 by the senses : but, by the senses, we have 
 no knowledge but of our sensations only ; 
 and our sensations have no resemblance of 
 anything that can be in a material world, f 
 The only proposition in this demonstration 
 which admits of doubt is, that, by our senses, 
 we have the knowledge of our sensations 
 only, and of nothing else. If there are ob- 
 jects of the senses which are not sensations, 
 his arguments do not touch them : they may 
 be things which do not exist in the mind, as 
 all sensations do ; they may be things of which, 
 by our senses, we have notions, though no 
 ideas ; just as, i)y consciousness and reflection, 
 we have notions of spirits and of their oper- 
 ations, without ideas or sensations. + [180] 
 
 Shall we say, then, that, by our senses, 
 we have the knowledge of our sensations 
 only ; and that they give us no notion of 
 anything but of our sensations ? Perhaps 
 this has been the doctrine of philosophers, 
 and not of Bishop Berkeley alone, otherwise 
 he would have supported it by arguments. 
 Mr Locke calls all the notions we have by 
 our senses, ideas of sensation ; and in this 
 has been very generally followed. Hence 
 it seems a very natural inference, that ideas 
 
 * Here again we have a criticism which proceeds 
 on the erroneous implication, that Locke meant by 
 sensation what Ueid himself did. If for sensation 
 we substitute perception, (and by sensation Locke 
 denoted both sensation proper and perception proper,) 
 there rem.-iins nothing to censure ; for Keid main- 
 tains that " our senses give us a direct and a distinct 
 notion of the j>r/war(/ qualities, and inform us uhal 
 they are in themselves " (infra, p. -i'^ ;) which is only 
 Locke's m -aning in other words, 'i he same observa- 
 tion applies to many of the following passages — H. 
 'l See the last note. — H. 
 
 t But, unless that be admitted, which the ratural 
 conviction of mankind certifies, that we have an 
 immediate perception— a consciousne.-.s — ot ''Xternal 
 and extended existences, it makes no differtnce, in 
 regard to the conclusion of the Idealist, whether 
 ■n'hat we are conscious of in perception be supposed 
 an entity in the mind, (an idea in Reid s meaning,) 
 or a modification of the mind, (a notion or concep- 
 tion.) See above, p. 128, noies ».— H. 
 
 of sensation are sensations. But philoso- 
 phers may err : let us hear the dictates of 
 common sense upon this point. 
 
 Suppose I am pricked with a pin, I ask, 
 Is the pain 1 feel, a sensation ? Undoubtedly 
 it is. There can be nothing that resembles 
 pain in any inanimate being. But I ask 
 again. Is the pin a sensation ? To this 
 question I find myself under a necessity of 
 answering, that the pin is not a sensation, 
 nor can have the least resemblance to any 
 sensation. The pin has length and thick- 
 ness, and figure and weight. A sensation 
 can have none of those qualities. I am not 
 more certain that the pain I feel is a sensa- 
 tion, than that the pin is not a sensation ; 
 yet the pin is an object of sense ; and I am 
 as certain that I perceive its figure and 
 hardness by my senses, as that I feel pain 
 when pricked by it.* 
 
 Having said so much of the ideas of sense 
 in Berkeley's system, we are next to con- 
 sider the account he gives of the ideas of 
 imagination. Of these he says. Principles, 
 § 28 — " I find I can excite ideas in my 
 mind at pleasure, and vary and shift the 
 scene as oft as I think fit. It is no more 
 than willing ; and straightway this or that idea 
 arises in my fancy ; and by the same power 
 it is obliterated, and makes way for another. 
 This making and unmaking of ideas, doth 
 very properly denominate the mind active. 
 Thus much is certain, and grounded on 
 experience. Our sensations," he says, " are 
 called real things ; the ideas of imagination 
 are more properly termed ideas, or images 
 of things ;"t that is, as I apprehend, they 
 are the images of our sensations. [181] 
 It might surely be expected that we should 
 be well acquainted with the ideas of imagin- 
 ation, as they are of our making ; yet, after 
 all the Bishop has said about them, I am 
 at a loss to know what they are. 
 
 I would observe, in the first place, with 
 regard to these ideas of imagination — that 
 they are not sensations ; for surely sensation 
 is the work of the senses, and not of imagin- 
 ation ; and, though pain be a sensation, the 
 thought of pain, when I am not pained, is 
 no sensation. 
 
 I observe, in the second place — that I can 
 find no distinction between ideas of imagin- 
 ation and notions, which the author says 
 are not ideas. I can easily distinguish be- 
 
 » This illustration is taken from Des Cartes. In 
 this paragraph, the term sensation is again not used 
 in the .extension given to it by the philosophers in 
 question — H. 
 
 f Berkeley's real words are — " 'I he ideas imprint, 
 ed.on the Senses by the Author of Nature are called 
 real things, and those excited in the Imagination 
 being less regular, vivid and constant, are iriore pro- 
 perly termed ji/oa* -or images of things, which they 
 copy and represent. But then our Sensations, be they 
 never so vivid and, dist net, are nevertheless ideas— 
 that is, they exist in the mind, or are perceived by 
 it, as truly as the ideas of its own framing."' Sect, 
 xxxiii. — H. 
 
 ri8o, i8i:i
 
 CHAP. XI. 1 BISHOP RSRKELEY'S SENTIMENTS OF IDEAS. 
 
 291 
 
 tween a notion and a sensation. It is one 
 thing to say, I liave the sensation of pain. 
 It is another thing to say, I have a notion of 
 pain. The last expression signifies no more 
 tliau that I understand what is meant by the 
 word pai/t. The first signifies that I really 
 feel pain. But I can find no distinction 
 between the notion of pain and the imagin- 
 ation of it, or indeed between the notion 
 of anything else, and the imagination of it. 
 I can, therefore, give no account of the 
 distinction which Berkeley makes between 
 ideas of imagination and notions, which, he 
 says, are not ideas. They seem to me per- 
 fectly to coincide.* 
 
 He seems, indeed, to say, that the ideas 
 of imagination differ not in kind from those 
 of the senses, but only in the degree of their 
 regularity, vivacity, and constancy, " They 
 are," says he, " less regular, vivid, and con- 
 stant." This doctrine was afterwards greed- 
 ily embraced by Mr Hume, and makes a 
 main pillar of his system ; but it cannot be 
 reconciled to common sense, to which Bishop 
 Berkeley professes a great regard. For, 
 according to this doctrine, if we compare the 
 state of a man racked with the gout, with 
 his state when, being at perfect ease, he 
 relates what he has suffered, the difference 
 of these two states is only this — that, in the 
 last, the pain is less regular, vivid, and con- 
 stant, than in the first. [182] We cannot 
 possibly assent to this. Every man knows 
 that he can relate the pain he suffered, not 
 only without pain, but with pleasure ; and 
 that to suffer pain, and to think of it, are 
 things wliich totally differ in kind, and not 
 in degree only.-f- 
 
 We see, therefore, upon the whole, that, 
 according to this system, of the most im- 
 portant objects of knowledge — that is, of 
 
 * Yet the distinction of iilca.i, strictly so called, and 
 notions, is one of the most common and important in 
 Ihephilosophy of Uiind. Nor do we owe it, as has been 
 asserted, to Berkeley. It was virtually taken by Ues 
 Cartes and the Cartesians, in their discrimination of 
 ideas of imapination and ide s.of intelligence; it was 
 in terms vindicated apainst I.ocke, by .--erjeaiit, Stil. 
 lingfleet,,Norris, Z. Mayiie, bishop Brown, and 
 others; lionnet signalized it; and, under the con- 
 trast i)f Ainchmnitiiii-n 'and Jiiyrijfi; it has long been 
 ari» established and classical discrimination with the 
 philosophers of Germany. Nay, Reid himself sug. 
 gests it in the distinction he requires between ima- 
 ginntum and conccjitkin, a'dislinction which he uiifor. 
 tunately did not. carry out, and which Mr Stewart 
 still more unhappily again perverted. See below, p. 
 371 The terms iiotion-nnA conci'pt.ion. (or more cor- 
 rectly (vz/kv/// in this) sense, I sliould- be reserved 
 tf»expres8 wh it we comprehend but cannot picture 
 in imagination, such as a relation, a general term, 
 ttc. 'Ihe word' /(/(■«, as one prostituted lo all mean, 
 iiigs, it were perhaps better altogether to discard. 
 A»for t!ic represi Illations of. imagination or phan- 
 tasy, I would employ the Urmt imdijf or pkanln.sin , it 
 being distinctly understood* that ttiese terms are ap- 
 plied to denote the ri:]ircxi-)ttatiim.i, not ol our visible 
 perceptions merely, a8 the terms taken literally would 
 indicate, but o( our lensible perceptions in general. — 
 
 1 There is here a confusion between pain ^-onsidcred 
 as a /edhitj, and as the idi/nitioti of a fii<iin(), to 
 wliii'ji thcphiloBopluTii would object —II. 
 
 [182, 18.S] 
 
 spirits, of their operations, and of the rela- 
 tions of things — we have no ideas at all ;" 
 we have notions of them, but not ideas ; the 
 ideas we have are those of sense, and those 
 of imagination. The first are the sensa- 
 tions we have by means of our senses, whose 
 existence no man can deny, because he is 
 conscious of them ; and whose nature hath 
 been explained by this author with great 
 accuracy. As to the ideas of imagination, 
 he hath left us much in the dark. He makes 
 them images of our sensations ; though, 
 according to his own doctrine, nothing can 
 resemble a sensation but a sensation. -j- He 
 seems to think that they differ from sensa- 
 tions only in the degree of their regularity, 
 vivacity, and constancy. But this cainiot 
 be reconciled to the experience of mankind; 
 and, besides this mark, which cannot be 
 admitted, he hath given us no other mark 
 by which they may be distinguished from 
 notions. Nay, it may be observed, that the 
 very reason he gives why we can have no 
 ideas of the acts of the mind about its ideas, 
 nor of the relations of things, is applicable 
 to what he calls ideas of imagination. 
 Principles, § 142. " We may not, I think, 
 strictly be said to have an idea of an active 
 being, or of an action, although we may be 
 said to have a notion of them. I have some 
 knowledge or notion of my mind, and its 
 acts about ideas, in as much as I know or 
 understand what is meant by these words. 
 [I will not say that the terms Idea and 
 Notion may not be used convertibly, if the 
 world will have it so. But yet it conduces to 
 clearness and propriety that we distinguish 
 things very different by different names.] 
 It is also to be remarked, that all relations 
 including an act of the mind, we cannot so 
 properly be said to have an idea, but rather 
 a notion of the relations and habitudes be- 
 tween things." From this it follows, that our 
 imaginations are not properly ideas, but no- 
 tions, because they include an act of the mind. 
 [ 1 83 ] For he tells us, in a passage already 
 quoted, that they are creatures of the mind, 
 of its own framing, and that it makes and 
 unmakes them as it thinks fit, and from this 
 is properly denominated active. If it be a 
 good reason why we have not ideas, but 
 notions oidy of relations, because they in- 
 clude an act of the mind, the same reason 
 nuist lead us to conclude, that our imagina- 
 tions are notions and not ideas, since tluey 
 are made and unmade by the mind as it 
 thinks fit : and, from this^ it is properly de- 
 nominated active. J 
 
 • 'J'hat is, no images of tnem in the phantasy. Reid 
 Inm.self would not say that such could be hinuiiiied,— 
 
 n. 
 
 t Berkeley does not say so in the meaning sup- 
 posed. — H. 
 
 t Imagination is an ambiguous word ; it memu 
 either the oct. of imagining, or the priuinct — / c , the 
 image imagined. Ol the foim r, Heiki'ley held, wp 
 can Ibrin a notion, but not an ulco, iii the 8en;e lit 
 
 u 2
 
 202 
 
 ON THE INTELLECTUAL POWERS. 
 
 fKSSAY ir. 
 
 When 80 much lias been written, and so 
 many disputes raised about ideas, it were 
 desirable that we knew what they are, and 
 to what catei^ory or class of beings they be- 
 long. In this we might expect satisfaction 
 in the writings of Bisliop Berkeley, if any- 
 where, considering his known accuracy and 
 precision in the use of words ; and it is for 
 this reason that I have taken so much pains 
 to find out what he took them to be. 
 
 After all, if I understand what he calls the 
 ideas of sense, they are the sensations which 
 we have by means of our five senses ; but 
 they are, he says, less properly termed ideas. 
 
 I understand, likewise, what he calls 
 notions ; but they, says he, are very differ- 
 ent from ideas, though, in the moderii way, 
 often called by that name. 
 
 The ideas of imagination remain, which 
 are most properly termed ideas, as he says ; 
 and, with regard to these, I am still very 
 nmch in the dark. When I imagine a lion 
 or an elephant, the lion or elephant is the 
 object imagined. The act of the mind, in 
 conceiving that object, is the notion, the 
 conception, or imagination of the object. If 
 besides the object, and the act of the mind 
 about it, there be something called the idea 
 of the object, I know not what it is.* 
 
 If we consult other authors who have 
 treated of ideas, we shall find as little satis- 
 faction with regard to the meaning of this 
 philosophical term. [184] The vulgar 
 have adopted it ; but they only mean by 
 it the notion or conception we have of any 
 object, especially our more abstract or gen- 
 eral notions. When it is thus put to sig- 
 nify the operation of the mind about objects, 
 whether in conceiving, remembering, or 
 perceiving, it is well understood. But phi- 
 losophers will have ideas to be the objects 
 of the mind's operations, and not the oper- 
 ations themselves. There is, indeed, great 
 variety of objects of thought. We can 
 think of minds, and of their operations ; of 
 bodies, and of their qualities and relations. 
 If ideas are not comprehended under any of 
 these classes, I am at a loss to comprehend 
 what they are. 
 
 In ancient philosophy, ideas were said to 
 be immaterial forms, which, according to 
 one system, existed from all eternity ; and, 
 according to another, are sent forth from 
 the objects whose form they are.+ In mo- 
 dern philosophy, they are things in the 
 mind, which are the immediate objects of 
 all our thoughts, and which have no exist- 
 ence when we do not think of them. They 
 are called the images, the resemblances, the 
 
 uses thp term ; whereas, of the latter, we can form 
 an idea by merely repeating the imaginatory act. — 
 
 • On lleid's misconception onthis point, see Note 
 B. — H. 
 
 f Nothing by the name of idea was sent off from 
 objects in the ancient philosophy. — H. 
 
 representatives of external objects of sense ; 
 yet they have neither colour, nor smell, nor 
 figure, nor motion, nor any sensible quality. 
 I reveretheauthority of philosophers, espe- 
 cially where they are so unanimous ; but 
 until I can comprehend what they mean by 
 ideas, I nmst thinkandspeak with the vulgar. 
 
 In sensation, properly so called, I can 
 distinguish two thing.s — the mind, or sen- 
 tient being, and the sensation. Whether 
 the last is to be called a feeling or an oper- 
 ation, I dispute not ; but it has no object 
 distinct from the sensation itself. If in 
 sensation there be a third thing, called an 
 idea, I know not what it is. 
 
 In perception, in remembrance, and in 
 conception, or imagination, I distinguish 
 three things — the mind that operates, the 
 operation of the mind, and the object of that 
 operation.* [185] That the object per- 
 ceived is one thing, and the perception of 
 that object another, I am as certain as I 
 can be of anything. The same may be 
 said of conception, of remembrance, of love 
 and hatred, of desire and aversion. In all 
 these, the act of the mind about its object is 
 one thing, the object is another thing. 
 There must be an object, real or imaginary, 
 distinct from the operation of the mind 
 about it. -J- Now, if in these operations the 
 idea be a fourth thing different from the 
 three I have mentioned, I know not what it 
 is, nor have been able to learn from all that 
 has been written about ideas. And if the 
 doctrine of philosophers about ideas con- 
 founds any two of these things which I have 
 mentioned as distinct — if, for example, it 
 confounds the object perceived with the 
 perception of that object, and represents 
 them as one and the same thing— such doc- 
 trine is altogether repugnant to all that I am 
 able to discover of the operations of my owii 
 mind ; and it is repugnant to the common 
 sense of mankind, expressed in the struc- 
 ture of all languages. 
 
 CHAPTER XII. 
 
 OP THE SKNTIMENTS OF MR HUME. 
 
 Two volumes of the " Treatise of Human 
 Nature" were published in 17^9, and the 
 third in 1740. The doctrine contained in 
 this Treatise was published anew in a more 
 popular form in Mr Hume's " Philosophical 
 Essays," of which there have been various 
 editions. What other authors, from the 
 
 • See Note B.— H. 
 
 + If there be an imaginary object distinct from the 
 act of imagination, where does it exist? It cannot 
 be external to the mind — for, ex hypothesi, it is ima- 
 ginary ; and, if in the mind iiself, distinct from the act 
 of imagination— why. what is this but the very crudest 
 doctrine of species ? For Reid's puzzle, see Note B. 
 
 [184, 185]
 
 CHAP. XII.] OF THE SENTIMENTS OF MR HUME. 
 
 293 
 
 time of Des Cartes, had called idea:), tin's 
 author distiuguislies into two kinds — to wit, 
 imprefsionsvLnA ideas ; comprehending under 
 the first, all our sensations, passions, and 
 emotions ; and under the last, the faint 
 images of these, when we remember or 
 imagine them. [186] 
 
 He sets out with this, as a principle that 
 needed no proof, and of which therefore he 
 offers none — that all the perceptions of the 
 human mind resolve themselves into these 
 two kinds, impressions and ileas. 
 
 As this proposition is the foundation upon 
 which the M'hole of INIr Hume's system 
 rests, and from which it is raised with great 
 acuteness indeed, and ingenuity, it were to 
 be wished that he had told us upon what 
 authority this fundamental proposition rests. 
 But we are left to guess, whether it is held 
 forth as a first principle, which has its 
 evidence in itself; or whether it is to be 
 received upon the authority of philosophers. 
 
 JMr Locke had tauglit us, that all the 
 mimediate objects of liuman knowledge are 
 ideas in the mind. Bishop lierkeley, pro- 
 ceeding upon this foundation, demonstrated, 
 very easily, that there is no material world. 
 And he thought that, for the purposes 
 both of philosophy and religion, we should 
 find no loss, but great benefit, in the want 
 of it. But the Bishop, as became his order, 
 was unwilling to give up the world of spirits. 
 He saw very well, that ideas are as unfit to 
 represent spirits as they are to represent 
 bodies. Perhaps he saw that, if we per- 
 ceive only the ideas of spirits, we shall find 
 the same difficulty in uiferring tlieir real 
 existence from the existenceof their ideas, as 
 we find in inferring the existence of matter 
 from the idea of it ; and, therefore, while he 
 gives up the material world in favour of the 
 system of ideas, he gives up one-half of that 
 system in favour of the world of spirits ; and 
 maintains tliat we can, without ideas, think, 
 and speak, and reason, intelligibly about 
 spirits, and what belongs to them. 
 
 Mr Hume shews no such partiality in 
 favour of the world of spirits. He adopts 
 the tlieory of ideas in its full extent ; and, 
 in consequence, shews that there is neither 
 matter nor mind in the universe ; nothing 
 but impressions and ideas. What we call 
 a 6w///, is only a bundle of sensations ; and 
 what we call the mind is only a bundle of 
 thoughts, passions, and emotions, without 
 any subject. [187] 
 
 Some ages hence, it will perhaps be 
 looked upon un a curious anecdote, that 
 two philosophers of the eighteenth ec'iitury, 
 of V(;ry distinguislied rank, were led, l)y a 
 j)liiloHoj)hical hypothesis, one, to di^believe 
 the existence of matter, and the otlu-r, to 
 disbelieve the existence both of matter and 
 of mind. Such an anecdote may not be 
 iiiiinHtructive, if it prove a warning to 
 [ 1H';--]8H) 
 
 philosophers to beware of hypotheses, espe- 
 cially when they lead to conclusions which 
 contradict the principles upon which all men 
 of common sense must act in common life. 
 
 The Egoists,* whom we mentioned be- 
 fore, were left far behind by Mr Hume ; 
 for they believed their own existence, and 
 perhaps also the existence of a Deity. But 
 Mr Hume's system does not even leave him 
 a self to claim the property of his impres- 
 sions and ideas. 
 
 A system of consequences, however ab- 
 surd, acutely and justly drawn from a few 
 principles, in very abstract matters, is of 
 real utility in science, and may be made 
 subservient to real knowledge. This merit 
 Mr Hume's metaphysical writings have in 
 a great degree. 
 
 We had occasion before to observe, that, 
 since the time of Des Cartes, philosophers, 
 in ti eating of the powers of the mind, have, 
 in many instances, confounded things which 
 the common sense of mankind has always 
 led them to distinguish, and which have 
 different names in all languages. Thus, in 
 the perception of an external object, all 
 languages distinguish three things— the 
 mi/id that perceives, the operation of that 
 mind, which is called perception, and the 
 ofijrcl perceived. -f- Nothing appears more 
 evident to a mind untutored by philosophy, 
 than that these three are distinct things, 
 which, though related, ought never to be 
 confounded. [188] The structure of all 
 languages supposes this distinction, and is 
 built upon it. Philosophers have intro- 
 duced a fourth thing in this process, which 
 they call the idea of the object, which is 
 supposed to be an image, or representative 
 of the object, and is said to be the imme- 
 diate object. The vulgar know nothing 
 about this idea ; it is a creature of j)hilo- 
 sophy,introduced to account for and explain 
 the manner of our perceiving external objects. 
 
 * In supplcmpiit to no'e § at p "269, supra, in re- 
 gard to the preteiuled sect of Kgoists, there is to be 
 added the following notices, which I did not recol- 
 lect till after that note was set:— 
 
 Wolf, (['stirlitilniiid lliiliiDiiilix, fj tiS,) after dividing 
 Idealists into K/nisIx and l'liir(i/i,''-ix,saysi,i)iti'riiliii, of 
 the former : — " I'uit pancis ahhinc annis assecla 
 qiiidani Mah'hr<nir}iii, I'arisiis. qui I'.goi-nniin pro. 
 fcssns est ((|Uod iiirmn niihi videlur) asscclas el ipse 
 nactiis est." in Ins Vi'riiiit'»fti(it' (ifilaiikn) van (uitt, 
 &c., c. I, ^ y, he also mentions tins iillir.ifltsdmste 
 Scctr. There is also an oration by t liristopher 
 Matthacns Pfaff', the Charcilkir of 'I'liebingen — 
 " l)e Ju/oisniOjiKird jiliilnsiip/iirii liiwrmi," in 172".;— 
 which I have not seen — I luis, what I formerly ha. 
 zarded, is still farther coiifirmid. All is vaf;ue and 
 contradictory hearsay in rcnard to the lld^itn. 'the 
 I'reiKh place them in Scotland ; the scotch in Hol- 
 land ; the (Germans in Fiance ; and they aie variously 
 stated as the immcdia e disciples of I)is Carles, 
 Malebranche, .Spimza. 'i here is certninly no reason 
 why an K^joistical Iileali>m should ni^t have been 
 exiilicitly )itoniiilt;a'cd liclore liclite, (whose iloctriiie, 
 however, i» not the same;) hut 1 have, as \ef, seen 
 no satisfactory Kroumis on which it can be slivun 
 that this had actua Iv been done — 11. 
 + Sec Notes H and ( . — fl.
 
 294 
 
 ON THE INTELLECTUAL POWERS. 
 
 [essay II. 
 
 It is pleasant to observe that, while philo- 
 sophers, for more than a century, have been 
 hiliouring, by means of ideas, to explain 
 perception and the other operations of the 
 mind, those ideas have by degrees usurped 
 the place of perception, object, and even of 
 the mind itself, and have supplanted those 
 very things they were brought to explain. 
 Des Cartes reduced all the operations of the 
 understanding to perception ; and what can 
 be more natural to those who believe that 
 they are only different modes of perceiving 
 ideas in our own minds ? Locke confounds 
 ideas sometimes with the perception of an 
 external object, sometimes with the external 
 object itself. In Berkeley's system, the idea 
 is the only object, and yet is often con- 
 founded with the perception of it. But, in 
 Hume's, the idea or the impression, which 
 is only a more lively idea, is mind, percep- 
 tion, and object, all in one : so that, by the 
 term perception, in Mr Hume's system, we 
 must understand the mind itself, all its 
 operations, both of understanding and will, 
 and all the objects of these operations. Per- 
 ception taken in this sense he divides into 
 our more lively perceptions, which he calls 
 impressions,* and the less lively, which he 
 calls ideas. To prevent repetition, I must 
 here refer the reader to some remarks made 
 upon this division, Essay I. chap. 1, in the 
 explication there given of the words, prr- 
 ceive, object, impression, [pp. 222, 223, 220.] 
 
 Philosophers have differed very much 
 with regard to the origin of our ideas, or 
 the sources whence they are derived. The 
 Peripatetics held that all knowledge is de- 
 rived originally from the senses ;-\- and this 
 ancient doctrine seems to be revived by 
 some late French philosophers, and by Dr 
 Hartley and Dr Priestley among the Brit- 
 ish. [189] Des Cartes maintained, that 
 many of our ideas are innate. Locke op- 
 posed the doctrine of innate ideas with 
 much zeal, and employs the whole first 
 book of his Essay against it. But he ad- 
 mits two different sources of ideas . the 
 operations of our external senses, which he 
 calls sensation, by which we get all our 
 ideas of body, and its attributes ; and re- 
 Jlection upon the operations of our minds, by 
 which we get the ideas of everything be- 
 
 • Mr Stewart {Ehin. III. Addenda to vol I. p. 
 43) seems to think that thp word impression was 
 first introduced as a technical ierm, into (he philo. 
 Bophy of mind, by Hume. This is not altogether 
 correct. For, besides the instances which Mr Stewart 
 himself adduces, of the illustration attempted, of the 
 phenomena of Ticmory from the analogy of an im. 
 press and a booc, words corresponding to impression 
 wcreamoijg the ancients familiarly applied to thepro- 
 cessescf external perception, imagination, &c.,in the 
 Atomistic, the Platonic, the Aristotelian, and the 
 Stoical philosophies ; while, amongmodern psycholo. 
 gists, (as Df s Cartes and Gassendi,; the term was like- 
 wise in common use — H. 
 
 t This is an incorrect, at K-ast a too unqualified, 
 itatcment. — H. 
 
 longing to the mind. The main design of 
 the second book of Locke's " Essay," is to 
 shew, that all our simple ideas, without 
 exception, are derived from the one or the 
 other, or both of these sources. In doing 
 this, the author i^ led into some paradoxes, 
 although, in general, he is not fond of para- 
 doxes : And had he foreseen all the con- 
 sequences that may be drawn from his ac- 
 count of the origin of our ideas, he would 
 probably have examined it more carefully." 
 
 Mr Hume adopts Locke's account of the 
 origin of our ideas ; and from that principle 
 infers, that we have no idea of substance, 
 corporeal or spiritual, no idea of power, no 
 other idea of a cause, but that it is something 
 antecedent, and ctmstantly conjoined to that 
 which we call its effect ; and, in a word, 
 that we can have no idea of anything but 
 our sensations, and the operations of mind 
 we are conscious of. 
 
 This author leaves no power to the mind 
 in framing its ideas and impressions ; and, 
 no wonder, since he holds that we have no 
 idea of power ; and the mind is nothing but 
 that succession of impressions and ideas of 
 which we are intimately conscious. 
 
 He thinks, therefore, that our impressions 
 arise from unknown causes, and that the 
 impressions are the causes of their corre- 
 sponding ideas. By this he means no more 
 but that they always go before the ideas ; 
 for this is all that is necessary to constitute 
 the relation of cause and effect. [190] 
 
 As to the order and succession of our 
 ideas, he holds it to be determined by three 
 laws of attraction or association, which he 
 takes to be original properties of the ideas, 
 by which they attract, as it were, or asso- 
 ciate themselves with other ideas which 
 either resemble them, or which have been 
 contiguous to them in time and place, or to 
 which they have the relations of cause and 
 effect. 
 
 We may here observe, by the way, that 
 the last of these three laws seems to be in- 
 cluded in the second, since causation, ac- 
 cording to him, implies no more than con- 
 tiguity in time and place. -j- 
 
 • At any rate, according to I.ocke, all our know- 
 ledge is a derivation from experience. — H . 
 
 + Mr Hume says—" I do not find that any philo. 
 sopher has attempted to enumerate or class all the 
 principles of Association ; a subject, however, that 
 seems to me very woithy of curiosity. To me there 
 appears to be only three principles of connection 
 among ideas: Resemblance — Contiguity in time or 
 place — Cause and Effect." — E.isai/s, yo\. ii., p. 24. — 
 Aristotle, and, after him, many other philosophers, 
 had, however, done this, and with even greater success 
 th.iii Hume himself. Aristotle's reduction is to the 
 four following heads : — I'roximity in time — Conti. 
 guity in place — Resemblance — Contrast. This is 
 more correct than Hume's; for Hume's second head 
 ought to be divided into two; while our connecting 
 any particular events in the relation of cause and 
 eft'tct, is itself the result of their otiserved proximity 
 in liine and contiguity in place; nay, to custom and 
 this en pirical coniiectio.i (as observed by Keid) iocs 
 
 riS9, 190]
 
 CHAP. XIII.] OF THE SENTIMENTS OF ANTHONY ARNAULD. 295 
 
 It is not my design at present to shew 
 how Mr Hume, upon the principles he has 
 borrowed from Locke and Berlieley, has, 
 with great acuteness, reared a system of 
 absolute sceptii-ism, wliich leaves no rational 
 ground to believe any one proposition, 
 rather than its contrary : my intention in 
 this pl;ice being only to give a detail of the 
 sentiments of philosophers concerning ideas 
 since they became an object of speculation, 
 and concerning the manner of our perceiv- 
 ing external objects by their means. 
 
 CHAPTER XIII. 
 
 OF THE SENTIMENTS OF ANTHONY ARNAULD. 
 
 In this sketch of the opinions of philoso- 
 phers concerning ideas, we must not omit 
 Anthony Arnauld, doctor of the Sorbonne, 
 who, in the year 1683, published his book 
 " Of True and False Ideas," in opposition 
 to the system of Malebranche before men- 
 tioned. It is only about ten years since I 
 could find this book, and I believe it is 
 rare.' [191] 
 
 Though Arnauld wrote before Locke, 
 Berkeley, and Hume, I liave reserved to 
 the last place some account of his senti- 
 ments, because it seems difficult to deter- 
 mine whether he adopted the common theory 
 of ideas, or whether he is singular in reject- 
 ing it altogether as a fiction of philoso- 
 phers. 
 
 The controversy between Malebranche 
 and Arnauld necessarily led them to con- 
 sider what kind of things ideas are — a point 
 upon which other philosophers had very 
 generally been silent. Both of them pro- 
 fessed the doctrine universally received : 
 that we perceive not material things imme- 
 diately — that it is their ideas that are the 
 immediate objects of our thought — and that 
 it is in the idea of everything that we per- 
 ceive its properties. 
 
 It is necessary to premise that both 
 these autliors use the word perception, as 
 Des Cartes had done before them, to sig- 
 nify every operation of the understand- 
 ing. -f " To think, to know, to perceive, are 
 the same thing," says Mr Arnauld, chap. 
 V. def. 2. It is likewise to be observed, 
 that the various operations of the mind are 
 l)y both called moilijicatinns of the mind. 
 Perhaps they were led into this plirase by 
 the Cartesian doctrine, that the essence of 
 tlic mind consists in thinking, as that of 
 body consists in extension. I apjjrehend, 
 
 Hume him«clf endeavour to reduce the principle of 
 Causality altogfthcr.—H. See Notes !)• ' andl)***. 
 
 • J he treatises of Arnauld in liia coritrover>y with 
 Malebraijche, are to he found in the lliirti/.cidlith 
 Vfilume of his collected works in Ito, 11. 
 
 t Kvery ajijtrehi-miie, or strictly axjnitive opera- 
 tw.n of the understanding. — H. 
 
 [l!)l,192] 
 
 therefore, that, when they make sensation, 
 perception, memory, and imagination, to 
 be various modifications of the mind, they 
 mean no more but that these are things 
 which can only exist in the mind as their 
 subject. We express the same thing, by 
 calling them various modes of thinking, or 
 various operations of the mind." 
 
 The things which the mind perceives, 
 says Malebranche, are of two kinds. They 
 are either in the mind itself, or they are 
 external to it. The things in the mind, 
 are all its diff'erent modifications, its sensa- 
 tions, its imaginations, its pure intellec- 
 tions, its passions and affections. These 
 are immediately perceived ; we are con- 
 scious of them, and have no need of ideas 
 to represent them to us. [192] 
 
 Tilings external to the mind, are either 
 corporeal or spiritual. With regard to the 
 last, he thinks it possible that, in another 
 state, spirits may be an immediate object 
 of our understandings, and so be perceived 
 without ideas ; that there may be such an 
 union of spirits as that they may imme- 
 diately perceive each other, and communi- 
 cate their thoughts mutually, without signs 
 and without ideas. 
 
 But, leaving this as a problematical point, 
 he holds it to be undeniable, that material 
 things cannot be perceived immediately, 
 but only by the mediation of ideas. He 
 thought it likewise undeniable, that the idea 
 must be immediately present to the mind, 
 that it must touch the soul as it were, and 
 modify its perception of the object. 
 
 From these principles we must neces- 
 sarily conclude, either that the idea is 
 some modification of the human mind, or 
 that it must be an idea in the Divine 
 Mind, which is always intimately present 
 with our minds. The matter being brought 
 to this alternative, Malebranche considers 
 first all the possible ways such a modifica- 
 tion may be produced in our mind as that 
 we call an idea of a material object, taking 
 it for granted always, that it nmst be an 
 object perceived, and something different 
 from the act of the mind in perceiving it. 
 He finds insuperable objections against 
 every hypothesis of such ideas being pro- 
 duced in our minds ; and therefore con- 
 cludes, that the inmicdiate objects of per- 
 ception are the ideas of the Divine Mind. 
 
 Against this system Arnauld wrote his 
 book " Of True and False Ideas." He 
 does not object to the alternative men- 
 tioned by Malebranche ; but lio maintains, 
 that ideas are modifications of our minds. 
 And, finding no other modification of tho 
 
 * Modes, or iiiotli/h-nliiiiis of mind, in the Cartetian 
 lichoiil, mean nicrelv what some recent pliilnsopherj 
 express liy stales of mind and iik lucle .liotli thu 
 (ieHveani\ ;y('.v.v/(ipha'nonicna iif the ciiiimioui snli- 
 jeot. I lie terms were ukcd by I)c» Cartes as well »ii 
 by hisdiiciplei.— H.
 
 290 
 
 ON THE INTELLECTUAL POU'EKS. 
 
 [kSSAV II 
 
 human iniiul which can be called the idea 
 of an external ol)jcct, he says it is only 
 another word for pcrcoiilion. Chap, v., def. 
 '.i. I iy;{] " 1 take the idea of an object, 
 and the perception of an object, to be the 
 same thing. I do not say whether there 
 may be otlier things to which the name of 
 idea may be given. But it is certain that 
 there are ideas taken in this sense, and th:it 
 these ideas are either attributes or modifi- 
 cations of (lur minds."" 
 
 This, I think, indeed, was to attack the 
 system of 3Ialcbranche upon its weak side, 
 and where, at the same time, an attack was 
 least expected. I'hilosophers had been so 
 unanimous in maintaining that we do not 
 perceive external objects immediately,-f- 
 but by certain representative images of 
 them called uleas^^ that Malebranche 
 might well think his system secure upon 
 that quarter, and that the-only question to 
 be determined was, in wliat subject those 
 ideas are placed, whether in the human or 
 in I he divine mind ? 
 
 But, says Mr Arnauld, those ideas are 
 mere chimeras — fictions of philosophers ; 
 there are no such beings in nature ; and, 
 therefore, it is to no purpose to inquire 
 whether they are in the divine or in the hu- 
 man mind. The only true and real ideas 
 are our perceptions, which§ are acknow- 
 ledged by all philosophers, and by INIale- 
 branche himself, to be acts or modifications 
 of our own minds. He does not say that 
 tl;e fictitious ideas were a fiction of Male- 
 branche. He acknowledges that they had 
 been very generally maintained by the 
 scholastic philosophers, II and points out, 
 very judiciously, the prejudices that had 
 led them into the belief of such ideas. 
 
 Of all the powers of our mind, the 
 
 • Arnauld did not allow that perceptions and 
 ideas are rcaUij or numerrcallijA\i\.\n%u\ihe<!i — i e., as 
 one thinj; from another thing; not even that tiicy 
 .ire )»orfa?/// distinguished — i. e , as a thing troni its 
 mode. He maintained that they ate JTrtrtviileiitical, 
 and only rationiilbt di.scriniin ited as vieivtd in dif- 
 ferent relations ; the iridivihibe mental moiliflcatiiju 
 being calkd a pi-fCfptiiin, by rtterciice to tlic inindor 
 thinkingsubji et— an iilra, by reference to the mediate 
 ohjiit or thing tlunight. Arnauld everywhere avows 
 tiiat he denies ideas only as existences distinct Irom 
 the art itself of percipiion — bee Oeuvrcs, t. xxxvui. 
 p|i. 187, l;w, l!J9, 3«).— H. 
 
 + Arnauld does not assert acainst Malebranch", 
 *' thal'ifc perceive external ohjecls immcdhilrln" — that 
 is, in themselves, and as existing. He was too accu. 
 rate for this. By an imwciiinte cognition, Keid 
 means merely the negation of the intermediation of 
 any third thing l>ttween the reality perceived and 
 the percipient mind. — H. 
 
 X Idea was not the word by which representative 
 images, distinct from the percipient act, had been 
 commonly called ; nor werephilo-ophcrs at a 1 unani- 
 mous in the adniissinn of such vicarious objects..— 
 See Notes G, L, M, N, O, &c.— H. 
 
 ^ '1 hat is, Perccptiuns, (thecognitive acts,) but not 
 ^7t•a.f,^the immediate objects ot those acts.) 'I'he latter 
 weie not acknowledged tiy .Malebranche and all phi. 
 loophers to be mere acts or modificati. ns oi our own 
 tniiiils. — H. 
 
 li lint by a d'.ttereiit n.im? H 
 
 external seiises are thought to be the 
 best understood, and their objects are the 
 most familiar. Hence we measure otlier 
 powers by them, and transfer to other 
 powers the language which properly be- 
 longs to them. The objects of sense must 
 be present to the sense, or within its 
 sphere, in order to their being perceived. 
 Hence, by analogy, we are led to say of 
 everything when we think of it, that it is 
 present to the mind, or in the mind. [194] 
 But this presence is metaphorical, or ana- 
 logical only ; and Arnauld calls it objec- 
 tive presence, to distinguish it from that 
 local presence which is required in objects 
 that are perceived by sense. But both 
 being called by the same name, they are 
 confounded together, and those things that 
 belong only to real or local presence, are 
 attributed to the metaphorical. 
 
 We are likewise accustomed to see objects 
 by their images in a mirror, or in water ; 
 and hence are led, by analogy, to think that 
 objects may be presented to the memory or 
 imagination in some similar manner, by 
 images, which^philosopher have called ideas. 
 
 By such prejudices and analogies, Arnauld 
 conceives, men have been led to believe that 
 the objects of memory and imagination 
 must be presented to the mind by images 
 or ideas ; and the philosophers have been 
 more carried away by these prejudices than 
 even the vulgar, because the use made of 
 this theory was to explain and account for 
 the various operations of the mind — a matter 
 in which the vulgar take no concern. 
 
 He thinks, however, that Des Cartes had 
 got the better of these prejudices, and that 
 he uses the word idea as signifying the same 
 thing with perception,* and is, therefore, 
 surprised that a disciple of Des Cartes, and 
 one who was so great an admirer of him as 
 Malebranche was, should be carric d away 
 by them. It is strange, indeed, that the 
 two most eminent disciples of Des Cartes 
 and his contemporaries should difJ'er so 
 essentially with regard to his doctrine con- 
 cerning ideas.-]- 
 
 I shall not attempt to give the reader an 
 account of the continuation of this contro- 
 versy between those two acute philosopliers, 
 in the subsequent defences and replies; be- 
 cause I have not access to see them. After 
 much reasoning, and some animosity, each 
 
 • 1 am convinced that in this interpretation of Des 
 Cartes' doctrine, Arnauld is right; for Des Carres 
 defines mental ideas — those, to wit, of which %cc arc. 
 conscious — to be " Cotjilaliones prout sunt tanquam 
 imagines — that is, tnoiights considered in their repre- 
 sent ative capacity ; iioristhereany passage to be found 
 in the writings or this philosopher, which, if properly 
 uiulerstO' d, warrants I he conclusion, that, by ideas ?« 
 tliemind, he meant auglit distinct fr.>m th*- cognitive 
 act. '1 he double use of the term idea by Des Cartes 
 has, however, ltd Ueid and others into a miscuii- 
 cept'.oii on thi- point. See Note N. — H. 
 
 t Keiri'sown dictr ne is far more ambigums. — H. 
 
 [19.'^, 1911
 
 tiiAP. XIII.] OF THE SENTIMENTS OF ANTHONY ARNAULD. 297 
 
 continued in his own opinion, and left his 
 antagonist where l;e found him. [195] 
 !Malebranche's opinion of our seeing all 
 things in God, soon died away of itself ; and 
 Arnauld's notion of ideas seems to have 
 been less regarded than it deserved, by the 
 philosophers that came after him ;• per- 
 haps for this reason, among others, that it 
 seemed to be, in some sort, given up by 
 himself, in his attempting to reconcile it to 
 the common doctrine concerning ideas. 
 
 From the account I have given, one 
 would be apt to conclude that Arnauld 
 totally denied the existence of ideas, in the 
 philosophical sense of that word, and that 
 he adopted the notion of the vulgar, who 
 acknowledge no object of perception but the 
 external object. But he seems very un- 
 willing to deviate so far from the common 
 track, and, what he had given up with one 
 hand, he takes back with the other. 
 
 For, firstf Having defined ideas to be the 
 same thing with perceptions, he adds this 
 qualification to his definition : — " I do not 
 here consider whether there are other things 
 that may be called ideas ; but it is certain 
 there are ideas taken in this sense. -f- I 
 believe, indeed, there is no philosopher who 
 does not, on some occasions, use the word 
 idea in this popular sense. 
 
 » The opinion of Arnauld in regard to the nature 
 of ideas was by no means overiociked by subsequent 
 philoso])hers. It is found fully detailed in almost 
 every systematic course or compend ol philoso|hy, 
 which appeared for a long time alter \U first promul. 
 gation, and in many of tliese it is the dcctrine re. 
 lommenileri as the true. Arnauld's was indeed the 
 opinion which latterly prevailed in the Cartesian 
 tchool. I'rom this It passed into other schools. Leib- 
 nitz, like Arnauld, repaided lileas. Notions, Kepre- 
 »entalions, as mere raodilications of the mind, (what 
 by his disciples, were called matovo/ ideas, like the 
 cerebral ideas of l)es ( artes, are out oftheques'ion,) 
 and no cruder opinion than this has ever subse- 
 quently found a looting in any of the German 
 hy.stems. 
 
 " 1 dnn't know," says .Mr Stewart, " of any author 
 wlio, prior to I)r Heid, has txpressid himself on this 
 fuliject with somiuli j stness aiid precision as I'ather 
 liuther, in the following passage of his treatise on 
 • First Truths :' — 
 
 " • If we confine ourselves to what is intelligible in 
 cur observations on /'(/raj, we "i'l say, they are no- 
 thing, l)ut mere modifications of the mind as a thiiik- 
 \nii beiiiK. The\ are called itkii.i with regard to the 
 object represented ; and perrejiliotis with regard lo 
 the faculty representing. It is manifest that our 
 Ideas, considered in this sense, are not more distin- 
 guished than motion is from a body moved.' — (F. 
 'Ml , Ett'iUsh Translation.y — i l.m. lii. Add. lo vol. i. 
 p. 10. 
 
 In this passapc, HuffiT only repeats the drctriiic of 
 Arnauld, in Arnauld's own words. 
 
 Ur Thomas lirown, on the other hand, has en- 
 deavoured to shew that th s doctiine, (which he 
 identifies with Iteid's,) had been long the catholic 
 opinion ; and thai Keid, in his atlack on the Ide.il 
 gy^lein, only reluted what had been already almost 
 universally exploiieil. In this alt inpt he is, how- 
 ever, gingulaily unfortunate; for, wiih the excep- 
 tion of I'rou.saz, all the examples he ad'luccs to 
 cv iice the prevalence of /■. rnauld's docirii eare only 
 ku many mistakes, 6» many instances in lact, which 
 might be alleged in coiilirmation of the very opposite 
 rriiiclusioii. t^cv JMiiilnityli Hiviiw, viA. hi., p. ISl- 
 I'Jfi-II. 
 
 + Sec following note.— II. 
 
 [ \<)r,, lOflJ 
 
 Secondly, He supports this popular sense 
 of the word by the authority of Des Cartes, 
 who, in liis demotistratiou of the existence 
 of God, from the idea of liim in our minds, 
 dei'ines an idea thus : — " By the word idea, 
 I understand that form of any thought, by 
 the immediate perception of which I am 
 conscious of that thought ; so that I can ex- 
 press nothing by words, with understanding, 
 without being certain that there is in mymind 
 the idea of that which is ex]iressed by the 
 words." This definition seems, indeed, to 
 be of the same import with tliat which is 
 given by Arnauld. But Des Cartes adds 
 a qualification to it, which Arnauld, in 
 quoting it, omits ; and which shews that 
 Des Cartes meant to limit his definition to 
 the idea then treated of — that is, to the idea 
 of the Deity ; and that there are other ideas 
 to which this definiJion does not apply. [!!)(>] 
 For he adds: — " And thus I give the name 
 of idea, not solely to the images painted in 
 the phantasy ; nay, in this place, I do not 
 at all give the name of ideas to those 
 images, in so far as they are painted in the 
 corporeal phantasy that is in some part of 
 the brain, but only in so far as they inform 
 the mind, turning its attention to that part 
 of the brain."* 
 
 Thirdly, Arnauld has employed the whole 
 of his sixth chapter, to shew that these ways 
 of speaking, common among philosophers — 
 to wit, that ice perceive not things imme- 
 diately ; that it is their ideas that ore the 
 immediale ohjccts of our thovghts; that it is 
 in the idea of everything that'we perceive i!s 
 pioperties — are not to be rejected, but are 
 true when rightly understood. He labours 
 to reconcile these expressions to his own 
 definition of ideas, by observing, that every 
 perception and every thought is necessarily 
 conscious of itself, and reilects upon itself ; 
 and that, by this consciousness and reflec- 
 tion, it is its own immediate object. Whence 
 he uifers, that the idea — that is, the percep- 
 tion — is the immediate object of perception. 
 
 This looks like a weak attempt to recon- 
 cile two inconsistent doctrines by one who 
 wishes to hold both.-f- It is true, thatcou- 
 .•iciousness always goes along with ]ieree]i- 
 tion ; but they are ditlVrent operations of 
 the mind, and they have their ditferent 
 objects. Consciousness is not perception, 
 nor is tlie object of consciousness the object 
 of pereet'tion.J The same may be sa d of 
 
 » Des Cartes here refers to the other meaning which 
 he gives to the term idea — that in, to denote the 
 materi.il motion, the organic .id'ection of the biain, 
 ot whiih the mind is not conscious. On Ileid's mis. 
 apprehension ot the ("aitesian doctrine touching thin 
 matter, sec Note N — M 
 
 ■(■ Arnauld's altemiit is nether weak nor inconsist. 
 cut. He had, in lact, a clc.irer view of the coiidi. 
 tuns ot the pro''leni llian Held himstlf, who has. In 
 fact.conlbundi d two upponitcdoctiineii. Sec Note C, 
 — H. 
 
 X On Reid's error in rcdiicins ronFclousiicss to n 
 special liiculiy.see Note H. — H.
 
 298 
 
 ON THE INTELLECTUAL POWERS. 
 
 [essay II. 
 
 every operation of mind that has an object. 
 Thus, injury is the object of resentment. 
 When I resent an injury, I am conscious 
 of my resentment — that is, my resentment 
 is the immediate and the only object of my 
 consciousness ; but it would be absurd to 
 infer from this, that my resentment is the 
 immediate object of my resentment. [197] 
 Upon the whole, if Arnauld — in conse- 
 quence of his doctrine, that ideas, taken 
 for representative images of external ob- 
 jects, are a mere fiction of the philosophers 
 — had rejected boldly the doctrine of Des 
 Cartes, as well as of the other philosophers, 
 concerning those fictitious beings, and all 
 the ways of speaking that imply their ex- 
 istence, I should have thought him more 
 consistent with himself, and his doctrine 
 concerning ideas more rational and more 
 intelligible than that of any other author of 
 my acquaintance who has treated of the 
 subject.* 
 
 CHAPTER XIV. 
 
 REFLECTIONS ON THE COMMON THEORY OP 
 IDEAS. 
 
 After so long a detail of the sentiments 
 of philosophers, ancient and modern, con- 
 cerning ideas, it may seem presumptuous 
 to call in question their existence. But no 
 philosophical opinion, however ancient, 
 however generally received, ought to rest 
 upon authority. There is no presumption 
 in requiring evidence for it, or in regulat- 
 ing our belief by the evidence we can find. 
 
 To prevent mistakes, the reader must 
 again be reminded, that if by ideas are 
 meant only the acts or operations of our 
 minds in perceiving, remembering, or ima- 
 gining objects, I am far from calling in 
 question the existence of those acts ; we 
 are conscious of them every day and every 
 hour of life ; and I believe no man of a 
 sound mind ever doubted of the real exist- 
 ence of the operations of mind, of which he 
 is conscious. Nor is it to be doubted that, 
 by the faculties which God has given us, 
 we can conceive things that are absent, as 
 well as perceive those that are within the 
 reach of our senses ; and that such concep- 
 tions may be more or less distinct, and 
 
 • Reids discontent with Arnauld i opinion — an 
 opinio 1 which is stated with great perej) cuity hy its 
 author— may be used as an argum nt to shew that his 
 own doctrine is, however ambiguous, that of intui. 
 live or immediate perce|)tion. (See XoteC ) Arnauld'e 
 thfory is identical with the finer form-nf rcprtseiita- 
 tive or mediate perception, and the difficulties of yiat 
 doctrme were not overlooked by his great antagonist. 
 Arnauld well objected that, when we see a horse, ac- 
 cording to Malebranehe, what we see is in reality 
 Godt himself; hut Malebranehe well rejoined, that, 
 when we see a horse, according to Arnauld, what we 
 Mte IS, in reality, only a modification of ourselves. — H. 
 
 more or less lively and strong. We have 
 reason to ascribe to the all-knowing and 
 all-perfect Being distinct conceptions of all 
 things existent and possible, and of all their 
 relations ; and if these conceptions are called 
 his eternal ideas, there ought to be no dis- 
 pute among philosophers about a word. 
 [198] The ideas, of whose existence I 
 require the proof, are not the operations of 
 any mind, but supposed objects of those 
 operations. They are not perception, re- 
 membrance, or conception, but things that 
 are said to be perceived, or remembered, or 
 imagined. 
 
 Nor do I dispute the existence of what 
 the vulgar call the objects of perception. 
 These, by all who acknowledge their exist- 
 ence, are called real things, not ideas. But 
 philosophers maintain that, besides these, 
 there are immediate objects of perception 
 in the mind itself : that, for instance, we 
 do not see the sun immediately, but an 
 idea ; or, as Mr Hume calls it, an impres- 
 sion in our own minds. This idea is said 
 to be the image, the resemblance, the re- 
 presentative of the -sun, if there be a sun. 
 It is from the existence of the idea that we 
 must infer the existence of the sun. But 
 the idea, being immediately perceived, there 
 can be no doubt, as philosophers think, of 
 its existence. 
 
 In like manner, when I remember, or 
 when I imagine anything, all men acknow- 
 ledge that there must be something that is 
 remembered, or that is imagined ; that is, 
 some object of those operations. The 
 object remembered must be something that 
 did exist in time past : the object imagined 
 may be something that never existed.* 
 But, say the philosophers, besides these 
 objects which all men acknowledge, there 
 is a more immediate object which really 
 exists in the mind at the same time we 
 remember or imagine. This object is an 
 idea or image of the thing remembered or 
 imagined. 
 
 The first reflection I would make on this 
 philosophical opinion is, that it is directly 
 contrary to the universal sense of men who 
 have not been instructed in philosophy. 
 When we see the sun or moon, we have no 
 doubt that the very objects which we im- 
 mediately see are very far distant from us, 
 and from one another. We have not the 
 least doubt that this is the sun and moon 
 which God created some thousands of years 
 ago, and which have continued to perform 
 their revolutions in the heavens ever since. 
 [199] But how are we astonished when 
 the philosopher informs us that we are mis- 
 taken in all this ; that the sun and moon 
 which we see are not, as we imagine, many 
 miles distant from us, and from each other, 
 
 • See Note B.— H 
 
 [197-199]
 
 CHAP, XIV.] REFLECTIONS ON THE THEORY OF IDEAS. 
 
 299 
 
 but that they are in our own mind ; that 
 they liad no existence before we saw them, 
 and will have none when we cease to per- 
 ceive and to think of them ; because the 
 objects we perceive are only ideas in our 
 own minds, which can have no existence a 
 moment longer than we think of them ! * 
 
 If a plain man, uninstructed in philoso- 
 phy, has faith to receive these mysteries, 
 how great must be his astonishment ! He 
 is brought into a new world, where every- 
 thing he sees, tastes, or touches, is an idea 
 — a fleeting kind of being which he can con- 
 jure into existence, or can anniliilate in the 
 twinkling of an eye. 
 
 After his mind is somewhat composed, it 
 will be natural for him to ask his philoso- 
 phical instructor, Pray, sir, are there then 
 no substantial and permanent beings called 
 the sun and moon, which continue to exist 
 whether we think of them or not ? 
 
 Here the philosophers differ. ]\Ir Locke, 
 and those that were before him, will answer 
 to this question, that it is very true there 
 are substantial and permanent beings called 
 the sun and moon ; but they never appear 
 to us in their own person, but by their re- 
 presentatives, the ideas in our own minds, 
 and we know nothing of them but what we 
 can gather from those ideas. 
 
 Bishop Berkeley and Mr Hume would 
 give a different answer to the question pro- 
 posed. They would assure the querist that 
 it is a vulgar error, a mere prejudice of the 
 ignorant and unlearned, to think that there 
 are any permanent and substantial beings 
 called the sun and moon ; that the heavenly 
 bodies, our own bodies, and all bodies what- 
 soever, are nothing but ideas in our minds ; 
 and that there can be nothing like the ideas 
 of one mind, but the ideas of another mind. 
 [200] There is nothing in nature but 
 minds and ideas, says the Bishop; — nay, 
 says Mr Hume, there is nothing in nature 
 but ideas only ; for what we call a mind is 
 nothing but a train of ideas connected by 
 certain relations between themselves. 
 
 In this representation of the theory of 
 ideas, there is nothing exaggerated or mis- 
 represented,»as far as I am able to judge ; 
 and surely nothing farther is necessary to 
 shew that, to the uninstructed in philoso- 
 phy, it must appear extravagant and vision- 
 ary, and most contrary to the dictates of 
 common understanding. 
 
 There is tiie less need of any farther 
 proof of thLs, tliat it is very amply acknow- 
 
 • Whether Rcid himself do not virtually liold tlii'* 
 latt o|)iiiion, see Note C. At any rate, it is very in- 
 correi t to say i hat the .v»n, moon, Stc , arc, or can he. 
 perceivcd.tiy ud as existent, and m their real dis. 
 tance in the heavens; all that we can he coRnisant 
 of (»upno«inK that wc are immnUntcli/ |ier(i|>iint of 
 the iiun-efio) \» i lie rayn of .light einanatiiiK trcpin Iheni, 
 aliid itkcoutact and relation wiili our oreaii of siuhi. 
 -M. ^ 
 
 lodged by Mr Hume in his Essay on the 
 Academical or Sceptical Philosophy. " It 
 seems evident," says he, " that men are car- 
 ried, by a natural instinct or prepossession, 
 to repose faith in their senses ; and that, 
 without any reasoning, or even almost be- 
 fore the use of reason, we always suppose an 
 external universe, which depends not on 
 our perception, but would exist though we 
 and every sensible creature were absent or 
 annihilated. Even the animal creation are 
 governed by a like opinion, and preserve this 
 belief of external objects in all their thoughts, 
 designs, and actions.'' 
 
 " It seems also evident that, whenimen 
 follow this blind and powerful instinct of 
 nature, they always suppose the very im- 
 ages presented by the senses to be the ex- 
 ternal objects, and never entertain any 
 suspicion that the one are nothing but re- 
 presentations of the other. This very table 
 which we see white, and feel hard, is be- 
 lieved to exist independent of our percep- 
 tion, and to be something external to the 
 mind which perceives it ; our presence be- 
 stows not being upon it ; our absence anni- 
 hilates it not : it preserves its existence 
 uniform and entire, independent of the situ- 
 ation of intelligent beings who perceive or 
 contemplate it. [201] 
 
 " But this universal and primary notion 
 of all men is soon destroyed by the slightest 
 philosophy, which teaches us that nothing 
 can ever be present to the mind, but an 
 image or perception ; and that the senses 
 are only the inlets through which these 
 images are received, without being ever 
 able to produce any immediate intercourse 
 between the mind and the object." 
 
 It is therefore acknowledged by this phi- 
 losopher, to be a natural instinct or pre- 
 possession, an universal and primary opinion 
 of all men, a primary instinct of nature, that 
 the objects which we immediately perceive 
 by our senses, are not images in our minds, 
 but external objects, and that their exist- 
 ence is independent of us and our percep- 
 tion. 
 
 In this acknowledgment, Mr Hume in- 
 deed seems to me more generous, and even 
 more ingenuous than Bishop Berkeley, who 
 would persuade us that his opinion does 
 not opj)ose the vulgar opinion, but only that 
 of the philosophers ; and that the external 
 existence of a material world is a philoso- 
 phical hypothesis, and not the natural dic- 
 tate of our perceptive powers. The Bisliop 
 shews a timidity of engaging such an adver- 
 sary, as a primary and universal ojiinion of 
 all men. He is rather fond to court its pa- 
 tronage. But the iiliilo.sopluT intrepidly gives 
 a defiance to thisiaiitagoiiist, and hocims to 
 glory inaconHii-t that was worthyof hisarni. 
 Ojitat (ijiiiitn nut fulvitin dcsci ndrir inoiife 
 I ■:i/ic7ii. After ali, I Husjiect that a jiliilo- 
 
 [200,201]
 
 300 
 
 ON THE INTELLECTUAL POVV^ERS. 
 
 [essay II. 
 
 sopher who wages war with tin's adversary, 
 will find himself in the same condition as a 
 nuithematician who should undertake to 
 demonstrate that there is no truth in the 
 axioms of mathematics. 
 
 A second reflection upon this subject is — 
 that the authors who have treated of ideas, 
 have generally taken their existence for 
 granted, as a thing that could not be called 
 in question ; and such arguments as they 
 have mentioned incidentally, in order to 
 prove it, seem too weak to support the con- 
 clusion. [202] 
 
 ]Mr LocUe, in the introduction to his 
 Essay, tells us, that he uses the word idea 
 to signify whatever is the immediate object 
 of thought ; and then adds, " I presume it 
 will be easily -granted me that there are 
 such ideas in men's minds ; every one is 
 conscious of them in himself; and men's 
 words and actions will satisfy him that they 
 are in others." I am indeed conscious of 
 perceiving, remembering, imagining; but 
 that the objects of these operations are 
 images in my mind, I am not conscious. 
 I am satisfied, by men's words and actions, 
 that they often perceive the same objects 
 which I perceive, which could not be, if 
 those objects were ideas in their ownniinds. 
 
 Mr Norris is the only author I have met 
 with, who professedly puts the question. 
 Whether material things can be perceived 
 by us immediately ? He has offered four 
 arguments to shew that they cannot. First, 
 " Material objects are without the mind, 
 and therefore there can be no union between 
 the object and the percipient." Answer, 
 This argument is lame, until it is shewn to 
 be necessary that in perception there should 
 be a union between the object and the per- 
 cipient. Second, " Material objects are 
 disproportioned to the mind, and removed 
 from it by the whole diameter of Being." 
 This argument I cannot answer, because I 
 do not understand it.* Third, "Because, 
 
 • This ronfession wouM, of itself, prove how super, 
 ficially Reid was versed in the literature of philo. 
 sopliy. Noiris's second argument is only the state- 
 meiit of a principle generally assumed by philosophers 
 — that the relation ot know-edge inftrs a correspond- 
 ence ot nature between the subject knowing, axtA the 
 object knnwn. I his principle has, perhaps, exerted 
 a move extensive influ'iice on s|)cculation than any 
 other ; and yet it has not been pi oved, and is incapatile 
 of jirfiof— nay, is contradicted by the evidence of 
 consciousness itself. To trace the influence of this 
 assumption would be, in (act, in a certain sort,- to 
 write the history of philosophy ; for, though this in- 
 fluence has never yet been historically dcvel ped, it 
 would be easy to shew that the belief, explicit 
 or implicit, that what knows and what is imme- 
 diately known must be of an analogous nature, lies 
 at the root of almost everv theory of cognii inn, from 
 the very earliest to the very latest speculatums. In 
 the more ancient pl.ilosophy of Greece, three philo- 
 sophers (A naxagorai^, Heraclitus, and .Akuia?(in) are 
 found, who prol^LSsed the opposite doctrine — that the 
 condition of knowledge lies in the contrariety, in the 
 natural antithesis, ot subject and object. Aristotle, 
 likcwie, in his treatise On the Soul, expressly con- 
 demns the prevalent opinion, that the similar is only 
 
 if material objects were immediate objects 
 of perception, there could be no physical 
 science — things necessary and immuable 
 being the only object of science." Anaiver, 
 Although things necessary and immutable 
 be not the immediate objects of perception, 
 they may be immediate objects of other 
 powers of the mind. Fourth, " If material 
 things were perceived by themselves, they 
 would be a true light to our minds, as being 
 the intelligilile form of our understandings, 
 and consequently perfective of them, and 
 mdeed superior to them." If I comprehend 
 anything of this mysterious argument, it 
 follows from it, that the Deity perceives 
 nothing at all, because nothing can be supe- 
 rior to his understanding, or perfective of 
 it. [203] 
 
 There is an argument which is hinted 
 at by Malebranche, and by several other 
 authors, which deserves to be more seriously 
 considered. As I find it most clearly ex- 
 pressed and most fully urged by Dr Samuel 
 Clarke, I shall give it in his words, in his 
 second reply to Leibnitz, § 4. " The soul, 
 without being present to the images of the 
 things perceived, could not possibly perceive 
 them. A living substance can only there 
 perceive, where it is present, either to the 
 
 cognisable by the similar ; but, in his Aicownchian 
 Iithics, he reverts to the doctrine which, in the for. 
 mer work, he had rejected. With these exceptions, 
 no principle, since the time of Empedocies, by whom 
 it seems first to have been explicitly announced, has 
 been more universally received, than this— that the 
 rrlatidu of knotiiedpe infers an aiialoaii of cxisUnce. 
 '1 his aiia'ogy may be of two degrees. ]\')iat knows, 
 and vluit is known, may be either similar or the 
 same; and, iT the principle itself be admitted, the 
 latter alternative is the more philosoi)hical. W ithout 
 entering on details, I may here notice some of the 
 more remarkable results of this principle, in both its 
 degrees. The general principle, not, indeed, exclu. 
 sively, but mainly, determined the admission of a 
 representative perception, by disallowing the possibil. 
 ity of any consciousness, or immediate knowledge of 
 matter, by a nature so diflferent from it as mind j 
 and, in its two degrees, it determined the various hy- 
 potheses, by which it was attempted to explain the 
 possibility of a representative or mediate perception 
 of the external world, 'i'o this principle, in its 
 lower potence — that what knows must be similar in 
 nature to what is immediately known— we owe the 
 intentional speeies of the Aristotelians, and the idens 
 of Malebranche and Berkeley. From this principle, 
 in its higher potence — that what knows must be 
 identical in nature with what is immediately known 
 — ihcre flow the (/nostic reasons of the Platonists, the 
 pre-existing forms or species of Theophrastus and The. 
 misiius, of Adelandus and Avicenna, the (mental) 
 ideas of lies Cartes and ArnnuU, the rep7-esentatio)is, 
 sensual ideas, 4c of Leibnitz and V\ olf, the phano. 
 mctia of Kant, the states of Brown, and (shall we 
 say?; the vacillating doctrine of perception held by 
 Keid himself. Meoiately, this principle was the 
 origin of many other famous theories : — of the hier- 
 archical gradation ot souls or faculties ot the Aristo. 
 telians ; of the vehicular media ot tLe Platonists; 
 of ihe hypotheses of a common intellect of .Alex, 
 ander, Themistius, .Averroes, Cajeianus, and Zabar. 
 clla ; ofthe vision in the deity of Malebranche; and of 
 the ( artesian and Leibnitzian lioctrines of assistance 
 and pre-estalilished harmony. Finally, to this pnn. 
 cipleis to be ascribed the refusal ol the evidence ot con. 
 sciousness to the primary fact, the duality of its per- 
 ception ; and theunitarian schemes ot Atisolutelden. 
 • ity, .Materialism, and Idealism, are the 'esults.— H. 
 
 [202, yo.s]
 
 CHAP. XIV.] REFLECTIONS ON THE THEORY OF IDEAS. 
 
 301 
 
 things tliemselves, (as the omnipresent God 
 is to the whole universe,) or to the images 
 of things, as the soul is in its proper srnso- 
 riurii.''' 
 
 Sir Isaac Xewton expresses the same 
 sentiment, but with his usual reserve, hi a 
 query only. 
 
 The ingenious Dr Porterfield, in liis Essay 
 concerning the motions of our eyes, adopts 
 this opinion with more coni'dence. His 
 \\ords are : " How body acts upon mind, 
 or mind upon body, I know not ; but this I 
 am very certain of, that nothing can act, or 
 be acted upon, where it is not ; and there- 
 fore our mind can never perceive anything 
 but its own proper modifications, and tlie 
 various states of the sensorium, to which it 
 is present : so that it is not the external 
 sun and moon which are in the heavens, 
 which our mind perceives, but only their 
 image or representation impressed upon the 
 sensorium. How the soul of a seeing man 
 sees the.-;e images, or how it receives those 
 ideas, from such agitations in the sensorium, 
 I knoNv not ; but I am sure it can never 
 perceive the external bodies themselves, to 
 Wiiicli it is not present." 
 
 These, indeed, are great authorities : but, 
 in matters of philosophy, we must not be 
 guided by authority, but by reason. Dr 
 Clarke, in the place cited, mentions slightly, 
 as the reason of his opinion, that " nothing 
 c:in any more act, or be acted upon when 
 it is not present, than it can be where it is 
 not." [204] And again, in his third 
 rejily to Leibnitz, § 11 — " We are sure the 
 somI cannot perceive what it is not present 
 to, because nothing can act, or be acted 
 upon, where it is not." The same reason 
 we see is urged by Dr P(n-terfield, 
 
 That nothing can act immediately where 
 it is not, I think must be admitted : for I 
 a:;rec with Sir Isaac Newton, that power 
 without substance is inconceivable. It is a 
 consequence of this, that nothing can be 
 acted upon immediately where the agent is 
 not present : let this, therefore be granted. 
 To make the reasoning conclusive, it is 
 farther necessary, that, when we perceive 
 objects, either they act upon us, or we act 
 upon them. This does nut appear self-evi- 
 dent, nor liave I ever met with any proof 
 of it. I sliall bi'iefly offer the reasons why I 
 think it ought not to bo admi'tted. 
 
 When we say that one being acts upon 
 another, we mean that some powei- or force 
 is exerted by the agent, which ])rodnces, or 
 lias a tendency to prioluce, a change in the 
 thing acted upon. If this be tlie meaning 
 of tlie phrase, as I conceive it is, there 
 appears no reason for asserting that, in 
 perception, either tlic object acts upon the 
 mind, or the mind upon tlie object. 
 
 An object, in being perceived, does not 
 act at all. I perceive the walla of the room 
 
 where I sit ; but they are perfectly inactive, 
 and therefore act not upon the mind. To 
 be perceived, is what logicians call an ex- 
 ternal denomination, which implies neither 
 action nor quality in the object perceived.* 
 Nor could men ever have gone into this 
 notion, that perception is owing to some 
 action of the object upon the mind, were 
 it not that we are so prone to form our 
 notions of the mind from some similitude 
 we conceive between it and body. Thought 
 in the mind is conceived to have some 
 analogy to motion in a body : and, as a body 
 is put in motion, by being acted upon by 
 some other body ; so we are apt to think the 
 mind is made to perceive, by some impulse 
 it receives from the object. But reasonings, 
 drawn from such analogies, ought never to 
 be trusted. [205] They are, indeed, the 
 cause.of most of our errors with regard to 
 the mind. And we might as well conclude, 
 that minds may be measured by feet and 
 inches, or weighed by ounces and drachms, 
 because bodies have those properties- i* 
 
 I see as little reason, in the second ))lace, 
 to believe that in perception the mind acts 
 upon the object. To perceive an object is 
 one thing, to act upon it is another ; nor is 
 the last at all included in the first. To say 
 that I act upon the wall by looking at it, is 
 an abuse of language, and has no meaning. 
 Logicians distinguish two kinds of opera- 
 tions of mind : the first' kind produces no 
 effect without the mind ; the last does. 
 The first they call hnrnancnt acts, the se- 
 cond Iraiisilive. All intellectual operations 
 belong to the first class ; they produce no 
 effect upon any external object. But, with- 
 out having recourse to logical distinctions, 
 every man ol common sense knows, that to 
 
 * This passage, among others that follow, afford 
 the f()un<iat:on ()(' an argument, to prove that lieid 
 is not orifjinal in his doctrine of Perception; but 
 that it was horrowed from the speciilationsof cert in 
 older ph losciphers, of which lie was aware. See 
 Note S —II. 
 
 f I'liis reasoning, which is not original to Reld, 
 (see No'.e S,) is not clearly or precisely expressed. 
 In asserting that " an ohject, in being perceived, docs 
 not act at all," our author cannot mean that, it does 
 not act ui>on the organ of sen^e; for this would not 
 only be absurd in iiselt, but in contradiction to his 
 own doctrine — " it being," he says, " a law of our 
 nature that we perceive not ixiernal objects un. 
 le.-s certain impressions he imuh: on Die. nercvs anil 
 brain." The assertion—" I perceive th<' walls ol the 
 room whe:e 1 sit, but they are perfectly inactive, 
 and. 111' re ore, act not on the iiiind," is c<|ually m- 
 correct in slateincnt. Tlir wiil/s of Ihr-riuini, strictly 
 60 called, assiirtdly do not act on ihe mind or on the 
 eye; but ihe walls of Ihe room, in tliis sens , are, in 
 fact, no object of (visuai) perception at all. VVIiat 
 we set in this lubtance, and what we loii»..'ly call the 
 walls of the room, is only the light rMlrciid from 
 their surface m lis relation to the oigan of sight— i i.'., 
 colour; but it cannot be allirnied that Ihe r,.ys of 
 IikIu do not act on and all' ct the retina, optic nerve, 
 and brain. What Arisioile (li!,tingui-.hed as the 
 coiiemiiniitants of sen.'atioi; — m f.tlrnsiiiii, niotiun, 
 piisilKin, \c. — are, indeed, perceived w-.tlinul any 
 lelat ve )iasic.n ol tl^e seii>e. Jiir, whatever may 
 be lieui's iiieaniiig, it is, at best, vague aiitl jnexpli. 
 c.t-11
 
 302 
 
 ON THE INTELLECTUAL POWERS. 
 
 [essay II. 
 
 tljiiik of an object, and to act upon it, are 
 very different things. 
 
 As we have, therefore, no evidence that, 
 in perception, the mind acts upon the object, 
 or the object upon the mind, but strong rea- 
 sons to the contrary, Dr Clarke's argument 
 against our perceiving external objects im- 
 mediately falls to the ground. 
 
 This notion, that, in perception, the object 
 must be contiguous to the percipient, seems, 
 with many other prejudices, to be borrowed 
 from analogy. In all the external senses, 
 there must, as has been before observed, be 
 some impression made upon the organ of 
 sense by the object, or by something coming 
 from the object. An impression supposes 
 contiguity. Hence we are led by analogy 
 to conceive something similar in the opera- 
 tions of the mind. Many philosophers re- 
 solve almost every operation of mind into 
 impressions and feelings, words manifestly 
 borrowed from the sense of touch. And it 
 is very natural to conceive contiguity neces- 
 sary between that which makes the impres- 
 sion, and that which receives it ; between 
 that which feels, and that which is felt. [206] 
 And though no philosopher will now pre- 
 tend to justify such analogical reasoning as 
 this, yet it has a powerful influence upon 
 the judgment, while we contemplate the 
 operations of our minds, only as they ap- 
 pear through the deceitful medium of such 
 analogical notions and expressions. * 
 
 When we lay aside those analogies, and 
 reflect attentively upon our perception of 
 the objects of sense, we must acknowledge 
 that, though we are conscious of perceiving 
 objects, we are altogether ignorant how it 
 is brought about ; and know as little how 
 we perceive objects as how we were made. 
 And, if we should admit an image in the 
 mind, or contiguous to it, we know as 
 little how perception may be produced by 
 this image as by the most distant object. 
 Why, therefore, should we be led, by a 
 theory which is neither grounded on evi- 
 dence, nor, if admitted, can explain any one 
 phenomenon of perception, to reject the 
 natural and immediate dictates of those 
 perceptive powers, to which, in the conduct 
 of life, we find a necessity of yielding im- 
 plicit submission ? 
 
 There remains only one other argument 
 that I have been able to find m-ged against 
 our perceiving external objects immediately. 
 It is proposed by Mr Hume, who, in the 
 essay already quoted, after acknowledging 
 that it is an universal and primary opi- 
 nion of all men, that we perceive external 
 
 » It is self-evident that, if a thing is to be an ob- 
 ject immediately known, it must be known as it 
 exists. Now, a bcdy must exist in some definite 
 part of space — in a certain place; it cannot, there, 
 tiore, be immediately known as existing, except it be 
 known in its place. But this supposes the mind to 
 be immediately present to it in si)ace.— H. 
 
 objects immediately, subjoins what fol- 
 lows : — 
 
 " But this universal and primary opinion 
 of all men is soon destroyed by the slightest 
 philosophy, which teaches us that nothing 
 can ever be present to the mind but an 
 image or perception ; and that the senses 
 are only the inlets through which these 
 images are received, without being ever 
 able to produce any immediate intercourse 
 between the mind and the object. The 
 table, which we see, seems to diminish as 
 we remove farther from it : but the real 
 table, which exists independent of us, suf- 
 fers no alteration. [207] It was, therefore, 
 nothing but its image which was present to 
 the mind. These are the obvious dictates of 
 reason ; and no man who reflects ever doubted 
 that the existences which we consider, when 
 we say this hovse,a.nd l/iat tree, are nothing 
 but perceptions in the mind, and fleeting 
 copies and representations of other exist- 
 ences, which remain uniform and independ- 
 ent. So far, then, we are necessitated, by 
 reasoning, to depart from the primary in- 
 stincts of nature, and to embrace a new 
 system with regard to the evidence of our 
 senses." 
 
 We have here a remarkable conflict be- 
 tween two contradictory opinions, wherein 
 all mankind are engaged. On the one side 
 stand all the vulgar, who are unpractised in 
 phi'osophical reseaches, and guided by the 
 uncorrupted primary instincts of nature. 
 On the other side stand all the philoso- 
 phers, ancient and modern ; every man, 
 without exception, who reflects. In this 
 division, to my great humiliation, I find 
 myself classed with the vulgar. 
 
 The passage now quoted is all I have 
 found in Mr Hume's writings upon this 
 point : and, indeed, there is more reason- 
 ing in it than I have found in any other 
 author ; I shall, therefore, examine it min- 
 utely. 
 
 First, He tells us, that " this universal 
 and primary opinion of all men is soon 
 destroyed by the slightest philosophy, which 
 teaches us that nothing can ever be pre- 
 sent to the mind but an image or percep- 
 tion." 
 
 The phrase of being present to the mind 
 has some obscurity ; but I conceive he 
 means being an immediate object of thought ; 
 an immediate object, for instance, of per- 
 ception, of memory, or of imagination. If 
 this be the meaning, (and it is the only 
 pertinent one I can think of,) there is no 
 more in this passage but an assertion of the 
 proposition to be proved, and an assertion 
 that philosophy teaches it. If this be so, 
 I beg leave to dissent from philosophy tiU 
 she gives me reason for what she teaches. 
 [1^08] For, though common sense and my 
 external senses demand my assent to their 
 
 ['^06-208]
 
 CHAP. XIV.] REFLECTIONS ON THE THEORY OF IDEAS. 
 
 303 
 
 dictates upon their own authority, yet phi- 
 losophy is not entitled to this privilege. 
 But, that I may not dissent from so grave 
 a personage without giving a reason, I give 
 this as the reason of my dissent : — I see 
 the sun when he shines ; I remember the 
 battle of Culloden ;* and neither of these 
 objects is an image or perception. 
 
 He tells us, in the next place, " That the 
 senses are only the inlets through which 
 these images are received." 
 
 I know that Aristotle and the schoolmen 
 taught that images or species flow from ob- 
 jects, and are let in by the senses, and strike 
 upon the mind ; but this has been so efiectu- 
 ally refuted by Des Cartes, by Malebranche, 
 and many others, that nobody now pretends 
 to defend it. Reasonable men consider it 
 as one of the most unintelligible and un- 
 meaning parts of the ancient system. To 
 what cause is it owing that modern philo- 
 sophers are so prone to fall back into this 
 hypothesis, as if they really believed it ? 
 For, of this proneness I could give many 
 instances besides this of Mr Hume ; and I 
 take the cause to be, that images in the 
 mind, and images let in by the senses, are 
 so nearly aUied, and so strictly connected, 
 that they must stand or fall together. The 
 old system consistently maintained both : 
 but the new system has rejected the doc- 
 trine of images let in by the senses, hold- 
 ing, nevertheless, that there are images in 
 the mind ; and, having made this unnatural 
 divorce of two doctrines which ought not 
 to be put asunder, that which they have 
 retained often leads them back involun- 
 tarily to that which they have rejected. 
 
 Mr Hume surely did not seriously be- 
 lieve that an image of sound is let in by the 
 ear, an image of smell by the nose, an 
 iniage of hardness and softness, of solidity 
 and resistance, by the touch. For, besides 
 the absurdity of the thing, which has often 
 been shewn, Mr Hume, and all modern 
 philosophers, mauitain that the images which 
 are the immediate objects of perception 
 have no existence when they are not per- 
 ceived ; whereas, if they were let in by the 
 senses, they must be, before they are per- 
 ceived, and have aseparateexistcnce. ['20!<] 
 
 He tell us, farther, that philosophy teaches 
 that the senses are unable to produce any 
 immediate intercourse between the mind 
 and the object. Here, I still require the 
 reasons that philosophy gives for this ; for, 
 to my apprehension, I immediately per- 
 ceive external objects, and this, I conceive 
 is the immediate intercourse iiere meant. 
 
 Hitherto I see nothing that can be called 
 
 • The«uncan be no immediate object of coiiscinus- 
 lc»s in perception, l)Ul only certain rays in connec- 
 tion witti the eye. 'J'lie t)attle of C'ulloileii can lie no 
 immediate otiject of'con«ciousne<H in rcmlleciion, l)ut 
 oidy a certain reprebcntalion by the iniiiU itgill — II. 
 [209, '21 Oj 
 
 an argument. Perhaps it was intended 
 only for illustration. The argument, the 
 only argument, follows ; — 
 
 The table which we see, seems to dimin- 
 ish as we remove farther from it ; but the 
 real table, which exists independent of us 
 sutlers no alteration. It was, therefore, 
 nothing but its image which was presented 
 to the mind. These are the obvious dic- 
 tates of reason. 
 
 To judge of the strength of this argu- 
 ment, it is necessary to attend to a distinc- 
 tion which is familiar to those who are con- 
 versant in the mathematical sciences — I 
 mean the distinction between real and ap- 
 parent magnitude. The real magnitude of 
 a line is measured by some known measure 
 of length — as inches, feet, or miles : the 
 real magnitude of a surface or solid, by 
 known measures of surface or of capacity. 
 This magnitude is an object of touch only, 
 and not of sight ; nor could we even have 
 had any conception of it, without the sense 
 of touch ; and Bishop Berkeley, on that 
 account, calls it tangible magnitude.* 
 
 Apparent magnitude is measured by the 
 angle which an object subtends at the eye. 
 Supposing two right lines drawn from the 
 eye to the extremities of the object making 
 an angle, of which the object is the sub- 
 tense, the apparent magnitude is measured 
 by this angle. [210] Th is apparent mag- 
 nitude is an object of sight, and not of 
 touch. Bishop Berkeley calls it visible 
 magnitude. 
 
 If it is asked what is the apparent mag- 
 nitude of the sun's diameter, the answer 
 is, that it is about thirty-one minutes of a 
 degree. But, if it is a!<ked what is the 
 real magnitude of the sun's diameter, the 
 answer must be, so many thousand miles, 
 or so many diameters of the earth. From 
 which it is evident that real magnitude, and 
 apparent magnitude, are things of a different 
 nature, though the name of magnitude is 
 given to both. The first has three dimen- 
 sions, the last only two ; the first is mea- 
 sured by a line, the last by an angle. 
 
 From what has been said, it is evident 
 that the real magnitude of a body must 
 continue unchanged, while the body is 
 unchanged. This we grant. But is it 
 likewise evident, that the apparent mag- 
 
 * The doctrine of lieid— that real mapnitude or 
 extension. is tlie objrct of touch,. uul of touch alone — 
 is altogether untenahle. I'or, in ihc first place, ma}?, 
 nitude appears greater or less in proportion to the 
 diHerent siae of the tactile organ in dillerent subjects ; 
 thus, an apple is larger to the hand of a child than to 
 the hand of an adult. I ouch, therefore, can, at best, 
 allbrd a knowledge of the relation of magnitudes, ui 
 proportion to the organ of this or that individual. 
 Hut, in l\\e mrdiiil place, even in the samciiuliviiliial, 
 the same object appears trcaler iir less, according as 
 it is ii.ncluHl by one part of the boily or by another. 
 On this subject, see Weber's " Annoiatinnes fie 
 I'ulsu, Ite-orptioiie, Auditu ct 'I'actu ;" J.cipsic, 
 l«:il.-Il
 
 304 
 
 ON THE INTELLKCTUAL POWERS. 
 
 [essay II 
 
 nitudc must continue tlie same while the 
 body is unclianged ? So far otherwise, 
 that every man who knows anything of 
 mathematics can easily demonstrate, that 
 tie same individual object, remaining in 
 the same place, and unchanged, must neces- 
 sarily vary in its apparent niatcnitude, ac- 
 cording as the point from which it is seen 
 is more or less distant ; and that its appa- 
 rent length or breadth will be nearly in a 
 reciprocal proportion to the distance of the 
 spectator. Tiiis is as certain as the princi- 
 ples of geometry.* 
 
 We must likewise attend to this — that, 
 though the real magnitude of a body is not 
 originally an object of sight, but of touch, 
 yet we learn by experience to judge of the 
 real magnitude in many cases by sight. 
 We learn by experience to judge of the 
 distance of a body from the eye within cer- 
 tain limits ; and, from its distance and ap- 
 parent magnitude taken together, we learn 
 to judge of its real magnitude. [211] 
 
 And this kind of judgment, by being 
 repeated every hour and almost every 
 minute of our lives, becomes, when we are 
 grown up, so ready and so habitual, that it 
 very much resembles the original perceptions 
 of our senses, and may not improperly be 
 called acquired. perception. 
 
 Whether we call it judgment or acquired 
 perception is a verbal difference. But it is 
 evident that, by means of it, we often dis- 
 cover by one sense things which are pro- 
 Iierly and naturally the objects of another. 
 Thus I can say, without impropriety, I hear 
 a drum, I hear a great bell, or I hear a 
 small bell ; though it is certain that the 
 figure or size of the sounding body is not 
 originally an object of hearing. In like 
 manner, we learn by experience how a 
 body of such a real magnitude and at such 
 a distance appears to the eye. But neither 
 its real magnitude, nor its distance fiora 
 the eye, are properly objects of sight, any 
 more than the form of a drum or the size 
 of a bell, are properly objects of hearing- 
 
 If these things be considered, it will ap- 
 pear that Mr Hume's argument hath no 
 force to support liis conclusion — nay, that it 
 leads to a contrary conclusion. The argu- 
 ment is this : the table we see seems to di- 
 minish as we remove farther from it ; that 
 is, its apparent magnitude is diminished ; 
 but the real table suffers no alteration — to 
 wit, in its real magnitude ; therefore, it is 
 
 • The whole confusion and difficulty in this ma'- 
 ter arises Irnm not determining Vv-hat is the true object 
 ill visual. pLTcepi ion. This is not any distant thing, 
 but merely the rays of light in immediate relation to 
 the organ. We therefore, see a different ohject at 
 every movement, liy which a different comiilement 
 of rays is rt-flecteil to theeye. The things (rom which 
 these rays are reflected are not, in truth, perceived at 
 all ; dnd to conceive tjiwn as objects (I perce|)tioii is 
 therefore erroneous, and produciiv;- of error. — H. 
 
 not the real table we see. I admit both the 
 premises in this syllogism, but I deny the 
 conclusion. The syllogism has what the 
 logicians call two middle terms: apparent 
 magnitude is the middle term in the fir.st 
 liremise ; real magnitude in the second. 
 Therefore, according to the rules of logic, 
 the conclusion is not justly drawn from the 
 premises ; but, laying aside the rules of 
 logic, let us examine it by the light of com- 
 mon sense. 
 
 Let us suppose, for a moment, that it is 
 the real table we. see : Must not this real 
 table seem to diminish as we remove farther 
 from it ? It is demonstrable that it must. 
 How then can this apparent diminution be an 
 argument that it is not the real table? [212] 
 When that which mu.st happen to the real 
 table, as we remove farther from it, does 
 actually happen to the table we see, it is ab- 
 surd to conclude from this, that it is not the 
 real table we see.* It is evident, therefore, 
 that this ingenious author has imposed upon 
 himself by confounding real magnitude with 
 apparent magnitude, and that his argument 
 is a mere sophism. 
 
 I observed that Mr Hume's argument 
 not only has no strength to support his con- 
 clusion, but that it leads to the contrary con- 
 clusion—to wit, that it is the real table we 
 see ;* for this plain reason, that the table 
 we see h.as precisely that apparent magni- 
 tude which it is demonstrable the real table 
 must have when placed at that distance. 
 
 This argument is made much stronger by 
 considering that the real table may be placed 
 successively at a thousand different dis- 
 tances, and, in every distance, in a thousand 
 different positions ; and it can be deter- 
 mined demonstratively, by the rules of 
 geometry and perspective, what must be its 
 apparent magnitude and apparent figure, in 
 each of those distances and positions. Let 
 the table be placed successively in as many 
 of those different distances and different po- 
 sitions as you will, or in them all ; open 
 your eyes and you shall see a table pre- 
 cisely of that apparent magnitude, and that 
 apparent figure, which the real table must 
 have in that distance and in that position. 
 Is not this a strong argument that it is the 
 real table you see ?* 
 
 In a word, the appearance of a visible 
 object is infinitely diversified, according to 
 its distance and position. The visible ap- 
 pearances are itmumerable, when we con- 
 fine ourselves to one object, and they are 
 multiplied according to the variety of ob- 
 jects. Those appearances have been mat- 
 ter of speculation to ingenious men, at least 
 since the time of Euclid. They have ac- 
 counted for all this variety, on the suppo- 
 sition that the objects we see are external. 
 
 » See last note.— H. 
 
 [211, 212]
 
 CHAP. XIV.] REFLECTIONS ON THE THEORY OF IDEAS. 
 
 305 
 
 and not in the mind itself. [213] The rales 
 they have demonstrated about the various 
 projections of the sphere, about the appear- 
 ances of the planets in their progressions, 
 stations, and retrogradations, and all the 
 rules of perspective, are built on the suppo- 
 sition that tlie objects of sight are external. 
 They can each of them be tried in thousands 
 of instances. In many arts and professions, 
 innumerable trials are daily made ; nor 
 were they ever found to fail in a single in- 
 stance. Shall we say that a false supposi- 
 tion, invented by the rude vulgar, has been 
 so luckv in solving an infinite number of 
 phienoniena of nature ? This, surely, would 
 be a greater prodigy than philosophy ever 
 exhibited : add to this, that, upon the con- 
 trary hypothesis — to wit, that the objects of 
 sight are internal — nr> account can be given 
 of any one of those appearances, nor any 
 physical cause assigned why a visible object 
 should, in any one case, have one apparent 
 figure and magnitude rather than another. 
 
 Thus, I have considered every argument 
 I have found advanced to prove the exist- 
 ence of ideas, or images of external things, 
 in the mind ; and, if no better arguments can 
 be found, I cannot help thinking that the 
 whole history of philosophy has never fur- 
 nished an instance of an opinion so unani- 
 /nously entertained by philosophers upon so 
 slight grounds. 
 
 A tlirl reflection I would make upon 
 this subject is, that philosophers, notwith- 
 standing their unanimity as to the existence 
 of ideas," hardly agree in any one thing 
 else concerning them. If ideas be not a 
 mere fiction, they must be, of all objects of 
 human knowledge, the things we have best 
 access to know, and to be acquainted with ; 
 yet there is nothing about which men differ 
 so mucli. 
 
 Some have held them to be self-existent, 
 otiiers to be in the Divine mind, others in 
 our own minds, and others in the brain or 
 scnsorium. I considered the hypothesis of 
 images in the brain, in the fourth chapter 
 of this essay. As to images in the mind, if 
 anything more is meant by the image of an 
 o!)jcct in the mind t'.ian the thought of that 
 object, I know not what it means. [214] 
 The distinct conception of an object may, 
 in a metaphorical or analogical sense, be 
 called an ima/e of it in the mind. But this 
 image is only the conception of the object, 
 and not tlieoliject conceived. It is an act 
 of tlie niin<l, and not the object of that act.-j- 
 
 Some ]iliilosopbers will have our ideas, or 
 a part of thorn, to bo innate ; otliers will 
 have thcni all to be adventitious : somo de- 
 rive them from tlie senses alone ; others 
 from sensation and reflection : some think 
 
 • This unanimity did, not exist. —M. 
 t Sec Notc« B .ind C II. 
 
 [213-215] 
 
 they are fabricated by the mind itself; 
 others that they are produced by externa 
 objects ; others that they are the immediate 
 operation of the Deity ; others say, that 
 impressions are the causes of ideas, and 
 that the causes of impressions are unknown : 
 some think that we have ideas only of ma- 
 terial objects, but none of minds, of their 
 operations, or of the relations of things ; 
 others will have the immediate object of 
 every thought to be an idea : some think 
 we have al)stract ideas, and that by this 
 chiefly we are distinguished from the brutes ; 
 others maintain an abstract idea to be an 
 absurdity, and that there can be no such 
 thing : with some they are<the immediate ob- 
 jects of thought, with others the only objects. 
 
 A fourth reflection is, that ideas do not 
 make any of the operations of the mind to 
 be better understood, although it was pro- 
 bably with that view that they have been 
 first invented, and afterwards so generally 
 received. 
 
 We are at a loss to know how we per- 
 ceive distant objects ; how we remember 
 things past ; how we imagine things that 
 have no existence. Ideas in the mind seem 
 to account for all these operations : they are 
 all by the means of ideas reduced to one 
 operation — to a kind of feeling, or imme- 
 diate perception of things present and in 
 contact witii the percipient ; and feeling is 
 an operation so familiar that we think it 
 needs no explication, but may serve to ex- 
 plain other operations. [215] 
 
 But this feeling, or immediate percep- 
 tion, is as difficult to be comprehended as 
 the things which we pretend to explain by 
 it. Two things may be in contact without 
 any feelmg or perception ; there must 
 therefore be in the perci[)ient a power to 
 feel or to j)erceive. How this power is pro- 
 duced, and how it operates, is quite beyond 
 the reach of our knowledge. As little can 
 we know whether tliis power must be limited 
 to things present, and in contact with us. 
 Xor can any man pretend to prove that the 
 Being who gave us the power to. perceiv« 
 tilings present, may no^ 'ive us tlie powes 
 to perceive things that a j distant,* to re- 
 member things past, and to conceive things 
 tliat never existed. 
 
 Some pliilosophers have endeavoiu'ed to 
 make ail our .senses to be only dili'erent 
 modifications of touch ;•!- a theory which 
 serves only to confound things that are dif- 
 ferent, and to perplex and daiken things 
 that are clear. The theory of ideas resembles 
 this, by reducing all the operations of the 
 
 * An immediatn percoption of things distant, is a 
 contradiction in terms. — tl. 
 
 t If an intirifiliiilc |)crce|/tion ho supposed, it can 
 only 1)0 rationally ftuiipcLscd of olijccts ;n in contact 
 with the organs of .sense lint, mi thi.s ease, .tII tho 
 sinse.s would, as Dcniorntns lield, lie, in a ccrtAia 
 Kort, only inodi(ication> of touch. — I!.
 
 306 
 
 ON THE INTELLECTUAL POWERS. 
 
 [essay it. 
 
 human understanding to the perception of 
 ideas in our own minds. This power of 
 perceiving ideas is as inexplicable as any of 
 the powers explained by it ; and the con- 
 tiguity of the object contributes nothing at 
 all to make it better understood ; because 
 there appears no connection between con- 
 tiguity and perception, but what is grounded 
 on prejudices drawn from some imagined 
 similitude between mind and body, and 
 from the supposition that, in perception, 
 the object acts upon the mind, or the mind 
 upon the object. We have seen how this 
 theory has led philosophers to confound 
 those operations of mind, which experience 
 teaches all men to be different, and teaches 
 them to distinguish in common language ; 
 and that it has led them to invent a lan- 
 guage inconsistent with the principles upon 
 which all language is grounded. 
 
 The last reflection I shall make upon this 
 theory, is — that the natural and necessary 
 consequences of it furnish a just prejudice 
 against it to every man who pays a due re- 
 gard to the common sense of mankind. [216] 
 
 Not to mention that it led the Pytha- 
 goreans and Plato to imagine that we see 
 only the shadows of external things, and 
 not the things themselves,* and that it gave 
 rise to the Peripatetic doctrine of sensible 
 specie!:, one of the greatest absurdities of 
 that ancient system, let us only consider the 
 fruits it has produced since it was new- 
 modelled by Des Cartes. That great re- 
 former in philosophy saw the absurdity of 
 the doctrine of ideas coming from external 
 objects, and refuted it effectually, after it 
 had been received by philosophers for'thou- 
 sands of years ; but he still retained ideas 
 in the brain and in the mind.-|- Upon this 
 foundation all our modern systems of the 
 powers of the mind are built. And the tot- 
 tering state of those fabrics, though built 
 by skilful hands, may give a strong suspicion 
 of the unsoundness of the foundation. 
 
 It was this theory of ideas that led Des 
 Cartes, and those that followed him, to think 
 it necessary to prove, by philosophical argu- 
 ments, the existence of material objects. 
 And who does not see that philosophy must 
 make a very ridiculous figure in the eyes of 
 sensible men, while it is employed in muster- 
 ing up metaphysical arguments, to prove 
 that there is a sun and a moon, an earth and 
 a sea ? Yet we find these truly great men, 
 Des Cartes, Malebranche, Arnauld, and 
 Locke, seriously employing themselves in 
 this argument.^ 
 
 Surely their principles led them to think 
 
 » See above, p. 262 col. b, note *— .H 
 
 t See Note N.— H. 
 
 t If Rcid do not allow that we are immediately 
 cognitive or conscious of the iion-efjo, his own doc 
 trine of perception differs not from that of other 
 philosophers in the necessity for this proof.— H. 
 
 that all men, from the beginning of the 
 world, believed the existence of these thmgs 
 upon insufficient grounds, and to think that 
 they would be able to place upon a more 
 rational foundation this universal belief of 
 mankind. But the misfortune is, that all 
 the laboured arguments they have advanced, 
 to prove the existence of those things we 
 see and feel, are mere sophisms : Not one 
 of them will bear examination. 
 
 I might mention several paradoxes, which 
 Mr Locke, though by no means fond of para- 
 doxes, was led into by this theory of ideas. 
 [217] Such as, that the secondary qualities 
 of body arc no qualities of body at all, but 
 sensations of the mind : That the primary 
 qualities of body are resemblances of our 
 sensations : That we have no notion of dur- 
 ation, but from the succession of ideas in 
 our minds : That personal identity consists 
 in consciousness ; so that the same indivi- 
 dual thinking being may make two or three 
 different persons, and several different think- 
 ing beings make one person : That judg- 
 ment is nothing but a perception oi the 
 agreement or disagreement of our ideas. 
 Most of these paradoxes I shall have oc- 
 casion to examine. 
 
 However, all these consequences of the 
 doctrine of ideas were tolerable, compared 
 with those which came afterwards to be dis- 
 covered by Berkeley and Hume : — That 
 there is no material world : No abstract 
 ideas or notions : That the mind is only a 
 train of related impressions and ideas, with- 
 out any subject on which they may be im- 
 pressed : That there is neither space nor 
 time, body nor mind, but impressions and 
 ideas only : And, to sum up all. That there 
 is no probability, even in demonstration it- 
 self, nor any one proposition more probable 
 than its contrary. 
 
 These are the noble fruits which have 
 grown upon this theory of ideas, since it 
 began to be cultivated by skilful hands. It 
 is no wonder that sensible men should be 
 disgusted at philosophy, when such wild 
 and shocking paradoxes pass under its name. 
 However, as these paradoxes have, with 
 great acuteness and ingenuity, been deduced 
 by just reasoning from the theory of ideas, 
 they must at last bring this advantage, that 
 positions so shocking to the common sense 
 of mankind, and so contrary to the decisions 
 of all our intellectual powers, will open men's 
 eyes, and break the force of the prejudice 
 which hath held them entangled in that 
 theory. [218] 
 
 CHAPTER XV. 
 
 ACCOUNT OF THE SYSTEM OF LEIBNITZ. 
 
 There is yet another system concerning 
 perception, of which I shall give some ac- 
 
 [216-218]
 
 CHAP. XV.] ACCOUNT OF THE SYSTEM OF LEIBNITZ. 
 
 307 
 
 count, because of the fame of its author. It 
 is the mvention of the famous German phi- 
 losopher Leibnitz, who, while he hvcd, held 
 the first rank among the Germans in all 
 parts of philosophy, as well as in mathe- 
 matics, in jurisprudence, in the knowledge 
 of antiquities, and in every branch both of 
 science and of literature. He was highly 
 respected by emperors, and by many kings 
 and princes, who bestowed upon him singu- 
 lar marks of their esteem. He was a par- 
 ticular favourite of our Queen Caroline, 
 consort of George II., with whom he con- 
 tinued his correspondence by letters, after 
 she came to the crown of Britain, till his 
 death. 
 
 The famous controversy between him and 
 the British mathematicians, whether he or 
 Sir Isaac Newton was the inventor of that 
 noble improvement in mathematics, called 
 by Newton, the method of fluxions, and by 
 Leibnitz the differential method, engaged 
 the attention of the mathematicians in 
 Europe for several years. He had likewise 
 a controversy with the learned and judicious 
 Dr Samuel Clarke, about several points of 
 the Newtonian philosophy which he dis- 
 approved. The papers which gave occasion 
 to this controversy, with all the replies and 
 rejoinders, had the honour to be transmitted 
 from the one party to the other, through 
 the hands of Queen Caroline, and were 
 afterwards published. 
 
 His authority, in all matters of philoso- 
 phy, is still so great in most parts of Ger- 
 many, that they are considered as bold 
 spirits, and a kind of heretics, who dissent 
 from him in anything. [211)] Carolus* 
 AVolfius, the must vohmiinous writer in 
 philosophy of this age, is considered as the 
 great interpreter and advocate of the Leib- 
 nitzian system, and reveres as an oracle 
 whatever has dropped from the pen of 
 Leibnitz. This author proposed two great 
 works upon the mind. The first, which I 
 have seen, he published with the title of 
 " P.sychologia Empiriea, seu Experiment- 
 alis."-|- The other was to have the title of 
 " Psychologia Rationalis ;" and to it ho. 
 refers for his explication of the theory of 
 Leibnitz with regard to the mind. But 
 whether it was published I have not learn- 
 ed-t 
 
 I must, therefore, take the short account 
 I am to give of this system from the writ- 
 ings of Leibnitz himself, without the light 
 which his interpreter Wolfius may have 
 thrown upon it. . 
 
 Leibnitz conceived the whole universe, 
 
 * Hi» name was Christian.— H. 
 
 + 'Ibis title is incorrcrf. It is " Ppyrhologia Km. 
 pirica metliodo scientifica ptriractala," *[C. 'J'lie 
 work ?|ip(;arcil in l':ti. — H. 
 
 t It wisp l)liiilu(l-in IT.'Jt. Sue li careless ignorance 
 of the uioiit (listiriguisheil works oil ttio subject of an 
 author's s|ieculation8, is peculiarly Jiritish. — H. 
 
 [,21 9, SyO] 
 
 bodies as well as minds, to be made up 
 of monads — that is, simple substances, each 
 of which is, by the Creator, in the begin- 
 ning of its existence, endowed with certaiir 
 active and perceptive powers. A monat^ 
 therefore, is an active substance, simple, 
 without parts or figure, which has within 
 itself the power to produce all the changes 
 it undergoes from the beginning of its ex- 
 istence to eternity. The changes which 
 the monad undergoes, of what kind soever, 
 though they may seem to us the effect of 
 causes operating from without, yet they 
 are only the gradual and successive evolu- 
 tions of its own internal powers, which 
 would have produced all the same changes 
 and motions, although there had been no 
 other being in the universe. 
 
 Every human soul is a monad joined to 
 an organized body, which organized body 
 consists of an infinite number of monads, 
 each having some degree of active and of 
 perceptive power in itself. But the whole 
 machine of the body has a relation to that 
 monad which we call the soul, which is, as 
 it were, the centre of the whole. [220] 
 
 As the universe is completely filled with 
 monads, without any chasm or void, and 
 thereby every body acts upon every other 
 body, according to its vicinity or distance, 
 and is mutually reacted upon by every other 
 body, it follows, says Leibnitz, that every 
 monad is a kind of living mirror, which re- 
 flects the whole universe, according to its 
 point of view, and represents the whole 
 more or less distinctly. 
 
 I cannot undertake to reconcile this part 
 of the system with what was before men- 
 tioned — to wit, that every change in a 
 monad is the evolution of its own original 
 powers, and would have happened thtmgh 
 no other substance had been created. But, 
 to proceed. 
 
 There are different orders of monads, 
 some higher and others lower. The higher 
 orders he calls dominant ; such is the hu- 
 man soul. The monads that compose the 
 organized bodies of men, animals, and plants, 
 are of a lowef order, and subservient to the 
 dominant monads. But every monad, of 
 whatever order, is a complete substance in 
 itself — indivisible, having no parts ; inde- 
 structible, because, having no parts, it can- 
 not perish by any kind of decomposition ; 
 it can only perish by annihilation, and we 
 have no reason to believe that God will ever 
 annihilate any of the beings which he has 
 made. 
 
 The monads of a lower order may, by a 
 regular evolution of their powers, rise to a 
 higher order. They '"ay successively bo 
 joined to organized bodies, of various forms 
 and different <lcgrces of perception ; but 
 they never die, nor cease to be m some de- 
 gree active and percipient. 
 
 x'iJ
 
 308 
 
 ON THE INTELLECTUAL POWERS. 
 
 [essay 
 
 if. 
 
 This philosopher makes a distinction be- 
 tween perception and what he calls upper- 
 ception. The first is common to all monads, 
 the last proper to the higher orders, among 
 which are human souls. [221] 
 
 By apperception he underst:inds that de- 
 gree of perception which retiects, as it were, 
 upon itself; by which we are conscious of 
 our own existence, and conscious of our 
 perceptions ; by which we can rellect upon 
 the operations of our own minds, and can 
 comprehend abstract truths. The mind, in 
 many operations, he thinks, particularly in 
 sleep, and in many actions common to us 
 with the brutes, has not this apperception, 
 although it is still filled with a multitude of 
 obscure and indistinct perceptions, of wliich 
 we are not conscious. 
 
 He conceives that our bodies and minds 
 are united in such a manner that neither 
 has any physical influence upon the otiier. 
 Each performs all its operations by its own 
 internal springs and powers ; yet the oper- 
 ations of one correspond exactly with those 
 of the other, by a pre-established harmony ; 
 just as one clock may be so adjusted as to 
 keep time with another, although each has 
 its own moving power, and neither receives 
 any part of its motion from the other. 
 
 So that, according to this system, all our 
 perceptions of external objects would be the 
 same, though external things had never 
 existed ; our perception of them would con- 
 tinue, although, by the power of God, they 
 should this moment be annihilated. We 
 do not perceive external things because they 
 exist, but because the soul was originally so 
 constituted as to produce in itself all its 
 successive clianges, and all its successive 
 perceptions, independently of the external 
 objects. 
 
 Every perception or apperception, every 
 operation, in a word, of the soul, is a neces- 
 sary consequence of the state of it imme- 
 diately preceding that operation ; and this 
 state is the necessary consequence of the 
 state preceding it ; and so backwards, until 
 you come to its first formation and consti- 
 tution, which produces, successively and 
 by necessary consequence, all its succes- 
 sive states to the end of its existence ; 
 [222] so tliat, in this respect, the soul, and 
 every monad, may be compared to a watch 
 wound up, which, having the spring of its 
 motion in itself, by the gradual evolution of 
 its own spring, produces all the successive 
 motions we observe in it. 
 
 In this account of Leibnitz's system con- 
 cerning monads and the pre-established 
 harmony, I have kept, as nearly as I could, 
 to his own expressions, i:i his " New System 
 of the Nature and Communication of Sub- 
 stances, and of the Union of Soul and 
 Body ;" and in the several illustrations of 
 that new system which he afterwards pub- 
 
 lished ; and in his " Principles of Nature 
 and Grace founded in Reason." I shall 
 now make a few remarks upon this system. 
 
 1. To pass over the irresistible necessity 
 of all human actions, which makes a part of 
 this system, that will be considered in an- 
 other place, I observe, first, that the dis- 
 tinction made between perception and ap- 
 perception is obscure and unphilosophical. 
 As far as we can discover, every operation 
 of our mind is attended with consciousness, 
 and particularly that which we call the per- 
 ception of external objects ; and to speak of 
 a perception of which we are not conscious, 
 is to speak without any meaning. 
 
 As consciousness is the only power by 
 which we discern the operations of our own 
 minds, or can form any notion of them, an 
 operation of mind of which we are not con- 
 scious, is, we know not what ; and to call 
 such an operation by the name of perception, 
 is an abuse of language. No man can per- 
 ceive an object without being conscious that 
 he perceives it. No man can think without 
 being conscious that he thinks. What men 
 are not conscious of, cannot therefore, with- 
 out impropriety, be called either perception 
 or thought of any kind. And, if we will 
 suppose operations of mind of which we are 
 not conscious, and give a name to such 
 creatures of our imagination, that name 
 must signify what we know nothing about." 
 [223] 
 
 2. To suppo.se bodies organized or un- 
 organized, to be made up of indivisible 
 monads which have no parts, is contrary to 
 all that we know of body. It is essential 
 to a body to have parts ; and every part of 
 a body is a body, and has parts also. No 
 number of parts, without extension or figure, 
 not even an infinite number, if we may use 
 that expression, can, by being put together, 
 make a whole that has extension and figure, 
 which all bodirs have. 
 
 3. It is contrary to all that we know of 
 bodies, to ascribe to the monad-s, of which 
 they are supposed to be compounded, per- 
 ception and active force. If a philosopher 
 thinks proper to say, that a clod of earth 
 both perceives and has active force, let him 
 bring his proofs. But he ought not to 
 expect that men who have understanding 
 will so far give it up as to receive without 
 proof whatever his imagination may sug- 
 gest. 
 
 4. This system overturns all authority of 
 our senses, and leaves not the least ground 
 to believe the existence of the objects of 
 
 • The .language in which Leibnitz expresses his 
 doclririe of latent moriificatiuns of mind, which, 
 thou{,'h out r.t consciousness, manife.-t their existen-^e 
 in their eHbcts, is objectionable; t- e dnctrint- itself is 
 not only true but of the very highest importance in 
 psychology, although it has never yet been appreci. 
 atedor even,undtrstood by any writer on philosophy 
 in this island. — H. 
 
 [221-2-23]
 
 CHAP. XV.] ACCOUNT OF THE SYSTEM OF LEIBNITZ. 
 
 309 
 
 sense, or the existence of anj-thing which 
 depends upon the authority of our senses ; 
 for our perception of objects, according to 
 this system, has no dependence upon any- 
 thing external, and would be the same as it 
 is, supposing external objects had never 
 existed, or that they were from this moment 
 annihilated. 
 
 It is remarkable that Leibnitz's system, 
 that of 3Ia'iebranche, and the common sys- 
 tem of ideas or images of external objects 
 in the mind, do :ill agree in overturning all 
 the authority of our senses ; and this one 
 thing, as long as men retain their senses, 
 will always make all these systems truly 
 ridiculous. 
 
 5. The last observation I shall make 
 upon this system, which, indeed, is equally 
 applicable to all the systems of Perception 
 1 have mentioned, is, that it is all hypo- 
 thesis, made up of conjectures and suppo- 
 sitions, without proof. The Peripatetics 
 supposed sensible species to be sent forth 
 by the objects of sense. The moderns sup- 
 pose ideas in the brain or in the mind. [224] 
 JMalebranche supposed that we jierceive 
 the ideas of the Divine mind. Leibnitz 
 supposed monads and a pre-established har- 
 mony ; and these monads being creatures 
 of his own making, he is at liberty to give 
 them what properties and powers his fancy 
 may suggest. In like manner, the Indian 
 philosopher supposed that the earth is sup- 
 ported by a huge elephant, and that the 
 elephant stands on the back of a huge tor- 
 toise. • 
 
 Such suppositions, while there is no proof 
 of them offered, are nothing but the fictions 
 of human fancy ; and we ought no more 
 to believe them, than we believe Homer's 
 fictions of Apollo's silver bow, or Minerva's 
 shield, or Venus's girdle. Such fictions in 
 poetry are agreetole to the rules of art : 
 they are intended to please, not to convince. 
 But the philoscy)hers would hav'e us to 
 believe their fictions, though t^ie ? :count 
 they give of the ])]ienomena of imt ire has 
 conmionly no more probability ^nan the 
 account that Homer gives of the plague in 
 the Grecian camp, from Apollo taking his 
 station on a neighbouring mountain, and 
 from his silver bow letting fly liis swift 
 arrows into the camp. 
 
 Men then only begin to have a true taste 
 h) pliilosophy, when they liave learned to 
 hold hypotheses in just contempt; and to 
 consider them iis the reveries of speculative 
 men, which will never have any similitude 
 to the works of God. 
 
 » It ia a di'puted point wlu-ther Ix?ibnitz wore 
 xrioiiH ill his niona'lology an<l jire ostalilislicd har. 
 mony. — H. 
 
 The Supreme Being has given us some 
 intelligence of his works, by what our senses 
 inform us of external things, and by what 
 our consciousness and retlection inform us 
 concerning the operations of our own minds. 
 Whatever can be inferred from these com- 
 mon informations, by just and sound reason- 
 ing, is true and legitimate philosophy : but 
 wl/at we add to this from conjecture is all 
 s/ urious and illegitimate. [225] 
 
 After this long account of the theories 
 idvanced by philosophers, to account for 
 our perception of external objects, I hope 
 it will appear, that neither Aristotle's theory 
 of sensible species, nor Malebranche's of 
 our seeing things in God, nor the common 
 theory of our perceiving ideas in our own 
 minds, nor Leibnitz's theory of monads 
 and a pre-established harmony, give any 
 satisfying account of this power of the mind, 
 or make it more intelligible than it is 
 without their aid. They are conjectures, 
 and, if they were true, would solve no diffi- 
 culty, but raise many new ones. It is, 
 therefore, more agreeable to good sense 
 and to sound philosophy, to rest satisfied 
 with what our consciousness and attentive 
 reflection discover to us of the nature oi 
 perception, than, by inventing hypotheses, 
 to attempt to explain things which are 
 above the reach of human understanding. 
 I believe no man is able to explain how we 
 perceive external objects, any more than 
 how we are conscious of those that are 
 internal. Perception, consciousness, me- 
 mory, and imagination, are all original and 
 simple powers of the mind, and parts of its 
 constitution. For this reason, though I 
 have endeavoured to shew that the theories 
 of philosophers on this subject are ill 
 grounded and insufficient, I do not attempt 
 to substitute any other theory in their 
 place. 
 
 Every man feels that perception gives 
 him an invincible belief of the existence of 
 that which lie perceives ; and that this 
 belief is not the effect of reasoning, but 
 the immediate consequence of perception.* 
 When philosophers have wearied them- 
 selves and their readers with their specula- 
 tions upon this suljject, they can neither 
 strengthen this belief, nor weaken it ; nor 
 can they shew how it is jiroduced. It jiuts 
 the philosojiher and the jieasant upon a 
 level ; and neither of them can give any 
 otlier reason for believing his senses, than 
 that he finds it impossible iur him to do 
 otherwise. [22G] 
 
 « In an immediate jierccrition of external thinpt, 
 the belief of their existence would not be a canfe. 
 iji/i'iicc (if tlie porce(iti()ii, but be invoHctI in tlie I>cr- 
 (•e|itioii itself.— 11.
 
 310 
 
 ON THE INTELLECTUAL POWERS. 
 
 [essay II. 
 
 CHAPTER XVI. 
 
 OF SENSATION. 
 
 Having finished what I intend, with 
 regard to that act of mind which we call 
 the perception of an external object, I 
 proceed to consider another, which, by our 
 constitution, is conjoined with perception, 
 and not witli perception only, but with 
 many other acts of our minds ; and that is 
 sensation- To prevent repetition, I must 
 refer the reader to the explication of this 
 word given in Essay I,, chap. i. 
 
 Almost all our perceptions have corre- 
 sponding sensations which constantly ac- 
 company them, and, on that account, are 
 very apt to be confounded with them. 
 Neither ought we to expect that the sens- 
 ation, and its corresponding perception, 
 should be distinguished in common lan- 
 guage, because the purposes of common 
 life do not require it Language is made 
 to serve the purposes of ordinary conversa- 
 tion ; and we have no reason to expect that 
 it should make distinctions that are not of 
 common use. Hence it happens, that a 
 quality perceived, and the sensation cor- 
 responding to that perception, often go under 
 the same name. 
 
 This makes the names of most of our 
 sensations ambiguous, and this ambiguity 
 hath very much perplexed philosophers. It 
 wiU be necessary to give some instances, to 
 illustrate the distinction between our sens- 
 ations and the objects of perception. 
 
 When I smell a rose, there is in this 
 operation both sensation and perception. 
 The agreeable odour I feel, considered by 
 itself, without relation to any external ob- 
 ject, is merely a sensation. [227] It affects 
 the mind in a certain way ; and this afl'ection 
 of the mind may be conceived, without a 
 thought of the rose, or any other object. 
 This sensation can be nothing else than it 
 is felt to be. Its very essence consists in 
 being felt ; and, when it is not felt, it is not. 
 There is no difference between the sensa- 
 tion and the feeling of it — they are one and 
 the same thing. It is for this reason that 
 we before observed that, in sensation, there 
 is no object distinct from that act of the 
 mind by which it is felt — and this holds 
 true with regard to all sensations. 
 
 Let us next attend to the perception 
 which we have in smelling a rose. Percep- 
 tion has always an external object ; and the 
 object of my perception, in this case, is that 
 quality in the rose which I discern by the 
 sense of smell. Observing that the agree- 
 able sensation is raised when the rose is 
 near, and ceases when it is removed, I am 
 led, by my nature, to conclude some quality 
 to be in the rose, which is the cause of this 
 
 sensation. This quality in the rose is the 
 object perceived ; and that act of my mind 
 by which I have the conviction and belief 
 of this quality, is what in this case I call 
 perception." 
 
 But it is here to be observed, that the 
 sensation I feel, and the quality in the rose 
 which I perceive, are both called by the 
 same name. The smell of a rose is the 
 name given to both : so that this name hath 
 two meanings ; and the distitiguishing its 
 different meanings removes all perplexity, 
 and enables us to give clear and distinct 
 answers to questions about which philoso- 
 phers have held much dispute. -j- 
 
 Thus, if it is asked, whether the smell 
 be in the rose, or in the mind that feels it, 
 the answer is obvious : That there are two 
 different things signified by the smell of a 
 rose ; one of which is in the mind, and can 
 be in nothing but in a sentient being ; the 
 other is truly and properly in the rose. The 
 sensation which I feel is in my mind. The 
 mind is the sentient being ; and, as the rose 
 is insentient, there can be no sensation, nor 
 anything resembling sensation in it. [228] 
 But this sensation in my mind is occasioned 
 by a certain quality in the rose, which is 
 called by the same name with the sensation, 
 not on account of any similitude, but be- 
 cause of their constant concomitancy. 
 
 All the names we have for smells, tastes, 
 sounds, and for the various degrees of heat 
 and cold, have a like ambiguity; and what 
 has been said of the smell of a rose may be 
 applied to them. They signify both a sens- 
 ation, and a quality perceived by means of 
 that sensation. The first is the sign, the 
 last the thing signified. As both are con- 
 joined by nature, and -as the purposes of 
 common life do not require them to be dis- 
 joined in our thoughts, they are both ex- 
 pressed by the same name : and this am- 
 biguity is to be found in all languages, be- 
 cause the reason of it extends to all. 
 
 The same ambiguity is found in the 
 names of such diseases as are indicated by 
 a particular painful sensation : such as the 
 toothache, the iicadache. The toothache 
 
 * This paragraph appears to be an explicit disa- 
 vowal of the doctrine ol an intuitive or immediate 
 perception. If, from a certain sensible feeling, or 
 sensation, (which is itself cognitive of no object,) lam 
 only determined by my nature to conclude (hat there 
 is some external quality which is the cause of this 
 sensation, and if this quality, thus only known as an 
 inference from its effect, be ihe ohject pcrcch-ed ; then 
 is perception not an act immediafely cognitive of 
 any existing object, and the object perceived is, in 
 fact, except as an imaqinary svinetltinq, unknown, 
 — H. 
 
 t In reference to this and the following paragraphs, 
 I may observe that the distinction ot subjective and 
 objective qualities here vaguely attempied, had been 
 already precisely accomplished by Aristotle, in his 
 discrimination of rxByinxai rmiTy.TH (qiialilatespati. 
 f/Urs,) and -tkOyi (pas.tionesj. In regard to the Car. 
 tesian distinction, which is equally precise, but of 
 which likewise Held is unaware, see above, p. 205, 
 col b, note*.— H 
 
 [227, 2281
 
 CHAP. XVI. J 
 
 OF SENSATION. 
 
 3U 
 
 signifies a painful sensation, which can only 
 be in a sentient being ; but it signifies also 
 a disorder in the body, which has no simili- 
 tude to a sensation, but is naturally con- 
 nected with it. 
 
 Pressing my hand with force against the 
 table, I feel pain, and I feel the table to be 
 hard. The pain is a sensation of the mind, 
 and there is nothing that resembles it in 
 the table. The hardness is in the table, 
 nor is there anything resembliug it in the 
 mind. Feeling is applied to both ; but in 
 a different sense ; being a word common'to 
 tlie act of sensation, and to that of perceiv- 
 ing by the sense of touch. 
 
 I touch the table gently with my hand, 
 and I feel it to be smooth, hard, and cold. 
 These are qualities of the table perceived by 
 touch ; but I perceive them by means of a 
 sensation which indicates them. This sens- 
 ation not being painful, I commonly give no 
 attention to it. [229] It carries my thought 
 immediately to the thing signified by it, and 
 is itself forgot, as if it had never been. But, 
 by repeating it, and turning my attention 
 to it, and abstracting my thought from the 
 thing signified by it, I find it to be merely 
 a sensation, and that it has no similitude to 
 the hardness, smoothness, or coldness of 
 the table, which are signified by it. 
 
 It is indeed difficult, at first, to disjoin 
 things in our attention which have always 
 been conjoined, and to make that an object 
 of reflection which never was so before ; 
 but some pains and practice will overcome 
 this difticulty in those who Jiave got the 
 habit of reflecting on the operations of their 
 own minds. 
 
 Although the present subject leads us 
 only to consider the sensations which we 
 have by means of our external senses, yet 
 it will serve to illustrate what has been said, 
 and, I apprehend, is of importance in itself, 
 to observe, that many operations of mind, 
 to which we give one name, and which we 
 always consider as one thing, are complex 
 in their nature, and made up of several 
 more simple ingredients; and of these ingre- 
 dients sensation very often makes one. Of 
 tliis we shall give some instances. 
 
 The appetite of hunger includes an un- 
 easy sensation, and a desire of food. Sens- 
 ation and desire are different .acts of mind. 
 The last, from its nature, must have an 
 object ; the first has no object. These two 
 ingredients may always bo separated in 
 thought — perliaj)S they sometimes are, in 
 reality ; but hunger includes both. 
 
 Benevolence towards our fellow-creatures 
 includes an agreeable feeling; but it includes 
 also a desire of the hapjiiness of others. 
 The ancients conniionly cillcd it desire. 
 Many moderns chuse rather to call it a feel- 
 ing. Both arc right : and they only err wlio 
 exclude eitlier of the ingredients. [2.'{(>] 
 r229- 2.T 1 1 
 
 Whether these two ingredients are neces- 
 sarily connected, is, perhaps, difficult for us 
 to determine, there being many necessary 
 connections which we do not perceive to be 
 necessary ; but we can disjoin them in 
 thought. They are different acts of the 
 mind. 
 
 An uneasy feeling, and a desire, are, in 
 Hke manner, the ingredients of malevolent 
 affections ; such as malice, envy, revenge. 
 The passion of fear includes an uneasy 
 sensation or feeling, and an opinion of 
 danger ; and hope is made up of the con- 
 trary ingredients. When we hear of a 
 heroic action, the sentiment which it raises 
 in our mind, is made up of various ingre- 
 dients. There is in it an agreeable feeling, 
 a benevolent affection to the person, and a 
 judgment or opinion of his merit. 
 
 If we thus analyse the various operations 
 of our minds, we shall find that many of 
 them which we consider as perfectly simple, 
 because we have been accustomed to call 
 them by one name, are compounded of more 
 simple ingredients ; and that sensation, or 
 feeling, which is only a more refined kind 
 0^ sensation, makes one ingredient, not 
 only in the perception of external objects, 
 but in most operations of the mind. 
 
 A small degree of reflection may satisfy 
 us that the number and variety of our sens- 
 ations and feelings is prodigious; for, to 
 omit all those which accompany our appe- 
 tites, passions, and affections, our moral 
 sentiments and sentiments of taste, even 
 our external senses, furnish a great variety 
 of sensations, differing in kind, and almost 
 in every kind an endless variety of degrees. 
 Every variety we discern, with regard to 
 taste, smell, sound, colour, heat, and cold, 
 and in the tangible qualities of bodies, is 
 indicated by a sensation corresponding to 
 it. 
 
 The most general and the most import- 
 ant division of our sensations and feelings, 
 is into the agreeable, the disagreeable, and 
 the indifterent. Everything we call plea- 
 sure, happiness, or enjoyment, on the one 
 hand ; and, on the other, everything we 
 call misery, pain, or uneasiness, is sensa- 
 tion or feeling ; for no man can for the pre- 
 sent be more happy or more miserable than 
 he feels himself to be. [2'M] He cannot 
 be deceived with regard to the enjoyment 
 or suffering of the jyresent moment. 
 
 But I ajiprehond that, besides the sens- 
 ations that are either agreeable or disagree- 
 able, th<!re is still a greater numlier that 
 are indiiferent.* To these we give so little 
 attention, that they have no name, and are 
 immediately forgot, as if tney had never 
 been ; und it requires attention to tlic ope- 
 
 Tlils li< n point in dispiitp among plillo'iipticrt 
 
 -H.
 
 312 
 
 ON THE INTELLECTUAL POWERS. 
 
 [essay II. 
 
 rations of our minds to be convinced of their 
 existence. 
 
 For this end we may observe, that, to a 
 good ear, every human voice is distinguish- 
 able from all others. Some voices are plea- 
 sant, some disagreeable ; but the far greater 
 part can neither be said to be one nor the 
 other. The same thing may be said of 
 other sounds, and no less of tastes, smells, 
 and colours ; and, if we consider that our 
 senses are in continual exercise while we are 
 awake, that some sensation attends every 
 object they present to us, and that familiar 
 objects seldom raise any emotion, pleasant 
 or painful, we shall see reason, besides the 
 agrecHble and disagreeable, to admit a third 
 class of sensations that may be called in- 
 different. 
 
 The sensations that are indifferent, are 
 far from being useless. They serve as 
 signs to distinguish things that differ ; and 
 the information we have concerning things 
 external, comes by their means. Thus, if 
 a man had no ear to receive pleasure from 
 the harmony or melody of sounds, he would 
 still find the sense of hearing of great 
 utility. Though sounds give him neithei 
 pleasure nor pain of themselves, they would 
 give him much useful information ; and the 
 like may be said of the sensations we have 
 by all the other senses. [232] 
 
 As to the sensations and feelings that are 
 agreeable or disagreeable, they differ much 
 not only in degree, but in kind and in dig- 
 nity. Some belong to the animal part of 
 our nature, and are common to us with the 
 brutes ; others belong to the rational and 
 moral part. The first are more properly 
 called sensations ; the last, feelings. The 
 French word sentiment is common to both.* 
 
 The intention of nature in them is for the 
 most part obvious, and well deserving our 
 notice. It has been beautifully illustrated 
 by a very elegant French writer,* in his 
 " Theorie des Sentiments Ayreahles." 
 
 The Author of Nature, in the distribution 
 of agreeable and painful feelings, hath 
 wisely and benevolently consulted the good 
 of the human species, and hath even shewn 
 us, by the same means, what tenor of con- 
 duct we ought to hold. For, first. The 
 painful sensations of the anunal kind are 
 admonitions to avoid what would hurt us ; 
 and the agreeable sensations of this kind 
 invite us to those actions that are necessary 
 to the preservation of the individual or of 
 the kind. Secondly., By the same means, 
 nature invites us to moderate bodily exer- 
 cise, and admonishes us to avoid idleness 
 and inactivity on the one hand, and exces- 
 sive labour and fatigue on the other. 
 
 • Some French philosophers, since Kcid, have 
 attempted the distinction of sentiment and sensation. 
 • — H 
 
 + l-evesqiie de Pouilly H. 
 
 Thirdly, The moderate exercise of all qui 
 rational powers gives pleasure. Fourthly, 
 Every species of beauty is beheld with 
 pleasure, and every species of deformity 
 with disgust ; and we shall find all that we 
 call beautiful, to be something estimable or 
 useful in itself, or a sign of something that 
 is estimable or useful. Fifthly, The bene- 
 volent affections are all accompanied with 
 an agreeable feeling, the malevolent with 
 the contrary. And, sixthly, The highest, 
 the noblest, and most durable pleasure is 
 that of doing well, and acting the part that 
 becomes us ; and the most bitter and pain- 
 ful sentiment, the anguish and remorse of 
 a guilty conscience. These observations, 
 with regard to the economy of nature in 
 the distribution of our painful and agree- 
 able sensations and feelings, are illustrated 
 by the author last mentioned, so elegantly 
 and judiciously, that I shall not attempt to 
 say anything upon them after him. [233] 
 
 I shall conclude this chapter by observ- 
 ing that, as the confounding our sensations 
 with that perception of external objects 
 which is constantly conjoined with them, 
 has been the occasion of most of the errors 
 and false theories of philosophers with re- 
 gard to the senses ; so the distinguishing 
 these operations seems to me to be the key 
 that leads to a right understanding of both. 
 
 Sensation, taken by itself, implies neither 
 the conception nor belief of any external 
 object. It supposes a sentient being, and 
 a certain manner in which that being is 
 affected ; but it supposes no more. Per- 
 ception implies an immediate conviction 
 and belief of something external — some- 
 thing different both from the mind that 
 perceives, and from the act of perception. 
 Things so different in their nature ought 
 to be distinguished ; but, by our constitu- 
 tion, they are always united. Every dif- 
 ferent perception is conjoined with a sensa- 
 tion that is proper to it. The one is the 
 sign, the other the thing signified. They 
 coalesce in our imagination. They are sig- 
 nified by one name, and are considered as 
 one simple operation. The purposes of life 
 do not require them to be distinguished. 
 
 It is the philosopher alone who has occa- 
 sion to distinguish them, when he would 
 analyse the operation compounded of them. 
 But he has no suspicion that there is any 
 composition in it ; and to discover this re- 
 quires a degree of reflection which has been 
 too little practised even by philosophers. 
 
 In the old philosophy, sensation and per- 
 ception were perfectly confounded. The 
 sensible species coming from the object, and 
 impressed upon the mind, was the whole; 
 and you might call it sensation or percep- 
 tion as you pleased- * 
 
 * This is not correct ; fir, in the riistiiictior of (he 
 
 [232, 23,-?]
 
 CHAP. XVII.] OF THE OBJECTS OF PERCEPTION. 
 
 313 
 
 Des Cartes and Locke, attending more 
 to the operations of their own minds, say, 
 that the sensations by whieli we have notice 
 of secondary qualities have no resemblance 
 to anything that pertains to body ; but they 
 did not see that this might, with equal justice, 
 be applied to the primary quaUties. [234] 
 Mr Locke maintains, that the sensations we 
 have from primary quahties are resem- 
 blances of those qualities. This shews how 
 grossly the most ingenious men may err 
 with regard to the operations of their minds. 
 It must, indeed, be acknowledged, that it is 
 much easier to liave a distinct notion of the 
 sensations that belong to secondary than 
 of those that belong to the primary quali- 
 ties.* The reason of this will appear in 
 the next chapter. 
 
 But, had Mr Locke attended with sufR. 
 cient accuracy to the sensationsf which he 
 was every day and every hour receiving 
 from primary qualities, he would have seen 
 that they can as little resemble any quality 
 of an inanimated being as pain can resemble 
 a cube or a circle. 
 
 What had escaped this ingenious philo- 
 sopher, was clearly discerned by Bishop 
 Berkeley. He had a just notion of sensa- 
 tions, and saw that it was impossible that 
 anything in an insentient being could re- 
 semble them ; a thing so evident in itself, 
 that it seems wonderful tluit it should have 
 been so long unknown. 
 
 But let us attend to the consequence of 
 this discovery. Philosophers, as well as the 
 vulgar, had been accustomed to comprehend 
 both sensation and perception under one 
 name, and to consider them as one uncom- 
 pounded operation. Philosophers, even 
 more than the vulgar, gave the name of 
 sensation to the whole operation of the 
 senses ; and all the notions we have of ma- 
 terial things were called ideas of sensation. 
 This led Bi^ho]) Berkeley to take one in- 
 gredient of a complex operation for the 
 whole ; and, having clearly discovered the 
 nature of sensation, taking it for granted 
 that all that the senses present to the mind 
 is sensation, which can have no resemblance 
 to anything material, he concluded that 
 there is no material world. [23')] 
 
 If tlie senses furnished us with no mate- 
 rials of thought but sensations, his conclu- 
 sion must be just ; for no sensation can give 
 us the conception of material things, far less 
 
 ipeciei imprfsm and spfcies cxprcsm, the distinc. 
 tion of icUKcttion and pi-rerptiuii could he percoivod ; 
 but, in point of (act, many even of the Aristoteli.iiis, 
 wlio admitted sppciej at all, allowed tliCMii only in one 
 «.r two ol the sensei. See Noies 1) * and M— II. 
 
 • 'I he reader will observe that Keid says, *• dis- 
 tinct uoticn <)/ the xfiuuthjns that heUnif; to the sr. 
 condary qualities," and not distinct notion ol the 
 secondary ()ualities thcmselve-t — II. 
 
 t Here ajjain the readi r wdl observe Ih d the term 
 i» tciitnlionx, afid not ;i(i/,'./;)it, o( the primary tjuali- 
 ties.- H. 
 
 any argument to prove their existence. But, 
 if it is true that by our senses we have not 
 only a variety of sensations, but likewise a 
 conception and an innnediate natural con- 
 viction of external objects, he reasons from 
 a false supposition, and his arguments fall 
 to the ground." 
 
 CHAPTER XVIL 
 
 OF THE OBJECTS OF PERCEPTION ; .IND, FIRST, 
 OF PRIMARY AND SECO.VDARV QUALITIES. 
 
 The objects of perception are the various 
 qualities of bodies. Intending to treat of 
 these only in general, and chiefly with a view 
 to e.xplain the notions which our senses 
 give us of them, I begin with the distinction 
 between primary and secondary qualities. 
 These were distinguished very early. The 
 Peripatetic system confounded them, and 
 left no difference. The distinction was again 
 revived by Des Cartes and Locke, and a 
 second time abolished by Berkeley and 
 Hume. If the real foundation of this dis- 
 tinction can be pointed out, it will enable us 
 to account for the various revolutions in the 
 sentiments of philosophers concerning it. 
 
 Every one knows that extension, divisi- 
 bility, figure, motion, solidity, hardness, 
 softness, and fluidity, were by i\Ir Locke 
 called primal y qualilits of bod// ; and that 
 sound, colour, taste, smell, and heat or cold, 
 were called aecondary qualities. Is there a 
 just foundation for this distinction ? Is 
 there anything common to the primary 
 which belongs not to the secondary ? And 
 what is it ? 
 
 I answer. That there appears to me to be 
 a real foundation for the distinction ; and it 
 is this — that our sen.ses give us a direct and 
 a distinct notion of the primary qualities, 
 and inform us what they are in themselves.+ 
 But of the secondary qualities, our senses 
 give us only a relative and obscure notion. 
 [23G] They inform us only, that they are 
 qualities that affect us in a certain manner 
 — that is, ])roduce in us a certain sensation ; 
 but as to what they are in themselves, our 
 senses leave us in the dark.:}: 
 
 * On this whole dislinrtioii, see Note D. f . — H. 
 
 t By the expression, " trliai tlicii are in thetnseh-es," 
 In reference to the primary qualities, and of " nln- 
 tin totion," in reference to the seccndary, Hoid 
 cannot mean that the lornier are known to us aliso- 
 liilcli/ and ill llii'msclrcs — that is, out n/ relation loour 
 cognitive faculties; for he elsewhere admits that all 
 our knowledjje is relative. I'arther, if " our senses 
 pive us a direet ami distinet mition of (he primary 
 (liialities, iind in/iirm \ s lelial lluij are in tlieniselres," 
 these (jualiiies, as known, iiiusf reseinhle, or be iden- 
 tical Willi, these (jualities as existillK. — ij. 
 
 t I'he (listiiictions of percept ion and sensation, and 
 of primary and secondary quahties, may be redureil 
 to one higher prine pie. Knowledge is partly c'vi c7- 
 (i'(', partly ,?»/yVi7/iv ,. liolli llie,5e eleliieiits are es.srii. 
 tial to every cognition, but in every coxniiion Ihey 
 are always in the inverse ratio of each other. Now
 
 314 
 
 ON THE INTELLECTUAL POV^^ERS. 
 
 [|essay II. 
 
 Every man capable of reflection may 
 easily satisfy himself that he has a perfectly 
 clear and distinct notion of extension, divisi- 
 bility, figure, and motion. The solidity of 
 a body means no more but that it excludes 
 other bodies from occupying the same place 
 at the same time. Hardness, softness, and 
 fluidity are different degrees of cohesion in 
 the parts of a body. It is fluid when it has 
 no sensible cohesion ; soft, when the cohe- 
 sion is weak ; and hard, when it is strong. 
 Of the cause of this cohesion we are ignor- 
 ant, but the thing itself we understand per- 
 fectly, being immediately informed of it by 
 the sense of touch. It is evident, therefore, 
 that of the primary qualities we have a clear 
 and distinct notion ; we know what they 
 are, though we may be ignorant of their 
 causes. 
 
 I observed, farther, that the notion we 
 have of primary qualities is direct, and not 
 relative only. A relative notion of a thing, 
 is, strictly speaking, no notion of the thing 
 at all, but only of some relation which it 
 bears to something else. 
 
 Thus, gravity sometimes signifies the tend- 
 ency of bodies towards the earth ; some- 
 times it signifies the cause of that tendency. 
 When it means the first, I have a direct 
 and distinct notion of gravity ; I see it, and 
 feel it, and know perfectly what it is ; but 
 this tendency must have a cause. We give 
 the same name to the cause ; and that cause 
 has been an object of thought and of specu- 
 lation. Now, what notion have we of this 
 cause when we think and reason about it ? 
 It is evident we think of it as an unknown 
 cause, of a known effect. This is a relative 
 notion ; and it must be obscure, because it 
 gives us no conception of what the thing is, 
 but of what relation it bears to something 
 else. Every relation which a thing un- 
 known bears to something that is known, 
 may give a relative notion of it ; and there 
 are many objects of thought and of dis- 
 course of which our faculties can give no 
 better than a relative notion. [237] 
 
 Having premised these things to explain 
 what is meant by a relative notion, it is evi- 
 dent that our notion of primary qualities is 
 not of this kind ; we know what they are, 
 and not barely what relation they bear to 
 something else. 
 
 It is otherwise with secondary qualities. 
 If you ask me, what is that quality or mo- 
 dification in a rose which I call its smell, I 
 am at a loss to answer directly. Upon re- 
 flection, I find, that I have a distinct notion 
 of the sensation which it produces in ray 
 mind. But there can be nothing like to 
 this sensation in the rose, because it is in- 
 
 in perception and Iheprimary qualities, the objective 
 element preponderates, whereas the subjective ele- 
 ment preponderates in sensation and the secondary 
 qualities. See Notes 1) and D * .— H. 
 
 sentient. The quality in the rose is some- 
 thing which occasions the sensation in me ; 
 but what that something is, I know not. 
 My senses give me no information upon 
 this point. The only notion, therefore, my 
 senses give is this — that smell in the rose is 
 an unknown quality or modification, which 
 is the cause or occasion of a sensation which 
 I know well. The relation which this un- 
 known quality bears to the sensation with 
 which nature hath connected it, isall I learn 
 from the sense of smelling ; but this is 
 evidently a relative notion. The same rea- 
 soning will apply to every .secondary quality. 
 
 Thus, I think it appears that there is a 
 reai foundation for the distinction of pri- 
 mary from secondary qualities ; and that 
 they are distinguished by this — that of the 
 primary we have by our senses a direct and 
 distinct notion ; but of the secondary only 
 a relative notion, which must, because it is 
 only relative, be obscure ; they are con- 
 ceived only as the unknown causes or occa- 
 sions of certain sensations with which we 
 are well acquainted. 
 
 The account I have given of this distinc- 
 tion is founded upon no hypothesis. [238] 
 Whether our notions of primary qualities 
 are direct and distinct, those of the se- 
 condary relative and obscure, is a matter 
 of fact, of which every man may have cer- 
 tain knowledge by attentive reflection upon 
 them. To this reflection I appeal, as the 
 proper test of what has been advanced, and 
 proceed to make some reflections on this 
 subject. 
 
 1- The primary qualities are neither sens- 
 ations, nor are they resemblances of sens- 
 ations. This appears to me self-evident. 
 I have a clear and distinct notion of each of 
 the primary qualities. I have a clear and 
 distinct notion of sensation. I can com- 
 pare the one with the other ; and, when I 
 do so, I am not able to discern a resembling 
 feature. Sensation is the act or the feeling 
 (I dispute not which) of a sentient being. 
 Figure, divisibility, solidity, are neither 
 acts nor feelings. Sensation supposes a 
 sentient being as its subject ; for a sensa- 
 tion that is not felt by some sentient being, 
 is an absurdity. Figure and divisibility 
 supposes a subject that is figured and divi- 
 sible, but not a subject that is sentient. 
 
 2. We have no reason to think that any 
 of the secondary qualities resemble any sens- 
 ation. The absurdity of this notion has 
 been clearly shewn by Des Cartes, Locke, 
 and many modern philosophers. It was a 
 tenet of the ancient philosophy, and is still 
 by m.any imputed to the vulgar, but only as 
 a vulgar error. It is too evident to need 
 proof, that the vibrations of a sounding 
 body do not resemble the sensation of sound, 
 nor the efiluvia of an odorous body the sens- 
 ation of smell. 
 
 I 237, 2381
 
 CHAP. 
 
 XVII.]] 
 
 OF THE OBJECTS OF PERCEPTION. 
 
 315 
 
 3. The distinctness of our notions of pri- 
 mary qualities prevents all questions and 
 disputes about their nature. There are no 
 different opinions about the nature of ex- 
 tension, figure, cr motion, or the nature of 
 any primary quality. Their nature is man- 
 ifest to our senses, and cannot be unknown 
 to any man, or mistaken by him, though 
 their causes may admit of dispute. [239] 
 
 The primary qualities are the object of 
 the mathematical sciences ; and the dis- 
 tinctness of our notions of them enables 
 as to reason demonstratively about them to 
 a great extent. Their various modifications 
 are precisely defined in the imagination, and 
 thereby capable of being compared, and their 
 relations determined with precision and cer- 
 tainty. 
 
 It is not so with secondary qualities. 
 Their nature not being manifest to the sense, 
 may be a subject of dispute. Our feeling 
 informs us that the fire is hot ; but it does 
 not inform us what that heat of the fire is. 
 But does it not appear a contradiction, to 
 say we know that tlie fire is hot, but we 
 know not what that heat is 'i I answer, 
 there is the same appearance of contradic- 
 tion in many things that must be granted. 
 We know that wine has an inebriating qua- 
 lity ; but we know not what that quality is. 
 It is true, indeed, that, if we had not some 
 notion of what is meant by the heat of fire, 
 and by an inebriating quality, we could 
 affirm nothing of either with understand- 
 ing. We have a notion of both ; but it -is 
 only a relative notion. We know that they 
 are the causes of certain known effects. 
 
 4. Tlie nature of secondary qualities is a 
 proper subject of philosophical disquisition ; 
 and in this philosophy has made some pro- 
 gress. It has been discovered, that the 
 sensation of smell is occasioned by the 
 effluvia of bodies ; that of sound by their 
 vibration. The disposition of bodies to re- 
 flect a particular kind of light, occasions the 
 sensation of colour. Very curious dis- 
 coveries have been made of the nature of 
 heat, and an amjile field of discovery in 
 these subjects remains. 
 
 5. We may see why the sensations be- 
 longing to secondary qualities are an object 
 of our attention, wiiilo tliosc which belons? 
 to tne primary are not. 
 
 The first are not only signs of the ob- 
 ject perceived, but they bear a capital part 
 in the notion we form of it. [240] We 
 conceive it only as that which occasions such 
 a sensation, and therefore cannot reflect 
 upon it witliout tliinkiiig-of the sensation 
 which it occasions: we have no other mark 
 whereby to distinguish it. 'J'ho thought of 
 a secondary quality, therefore, always car- 
 ries us back to the sensation which it pro- 
 duces. We give the same name to botli, 
 and are apt to confound them togetlicr. 
 r239-2tll 
 
 But, having a clear and distinct conception 
 of primary qualities, we have no need, when 
 we think of them, to recall their sensations. 
 When a primary quality is perceived, the 
 sensation immediately leads our thought to 
 the quality signified by it, and is itself for- 
 got. We have no occasion afterwards to 
 reflect upon it ; and so we come to be as 
 little acquainted with it as if we had never 
 felt it. This is the case with the sensations 
 of all primary qualities, when they are not 
 so painful or pleasant as to draw our atten- 
 tion. 
 
 When a man moves his hand rudely 
 against a pointed hard body, he feels pain, 
 and may easily be persuaded that this pain 
 is a sensation, and that there is nothing 
 resembling it in the hard body ; at the same 
 time, he perceives the body to be hard and 
 pointed, and he knows that these qualities 
 belong to the body only. In this case, it is 
 easy to distinguish what he feels from what 
 he perceives. 
 
 Let him again touch the pointed body 
 gently, so as to give him no pain ; and now 
 you can hardly persuade him that he feels 
 anything but the figure and hardness of the 
 body : so difficult it is to attend to the sens- 
 ations belonging to primary qualities, when 
 they are neither pleasant nor painful. They 
 carry the thought to the external object, 
 and immediately disappear and are forgot. 
 Nature intended them only as signs ; and 
 when they have served that purpose they 
 vanish. 
 
 We are now to consider the opinions 
 both of the vulgar and of philosophers upon 
 this subject. [241] As to the former, it 
 is not to be expected that they should make 
 distinctions which have no connection with 
 the common affairs of life ; they do not, 
 therefore, distinguish the primary from the 
 secondary qualities, but speak of both as 
 being equally qualities of the external ob- 
 ject. Of the primary qualities they have a 
 distinct notion, as they are immediately and 
 distinctly, perceived by the senses ; of the 
 secondary, their notions, as I apprehend, 
 are confused and indistinct, rather than 
 erroneous. A secondary quality is the 
 unknown cause or occasion of a well-known 
 effect ; and the same name is conmion to 
 the cause and the cfl'ect. Now, to dis- 
 tinguish clearly the difi'erent ingredients of a 
 complex notion, and, at the same time, the 
 different meanings of an ambiguous word, 
 is the work of a pliilosoiihcr ; and is not 
 to be expected of the vulgar, wlien tluir 
 occasions»do not re((uirc it. 
 
 I grant, fhcrefon', that the notion wliich 
 the vulgar have of secondary (|uiilitiis, is 
 indistinct and inaccurate. But then? seems 
 to be a contradiction between the vulgar 
 and the j)hi]osoiiher \\\>m\ this subject, and 
 (■;ic'h cliargcH the iitiier with a gross al)-
 
 316 
 
 ON THE INTELLECTUAL POWERS. 
 
 LKSSAY II. 
 
 surdity. The vulgar say, that fire is hot, 
 and snow cold, and sugar sweet ; and that 
 to deny this is a gross absurdity, and con- 
 tradicts tlie testimony of our senses. The 
 philosopher says, that heat, and cold, and 
 sweetntss, are nothing but sensations in 
 our minds ; and it is absurd to conceive 
 that these sensations are in the fire, or in 
 the snow, or in the sugar. 
 
 I believe this contradiction, between the 
 vulgar and the philosopher, is more apparent 
 than real ; and that it is owing to an abuse 
 of language on the part of the philosopher, 
 and to indistinct notions on the part of the 
 vulgar. The iihilosojiher says, there is no 
 heat in the fire, meaning that the fire has 
 not the sensation of heat. His meaning is 
 just; and the vulgar will agree with him, 
 as soon as they understand his meaning : 
 But his language is improper ; for there is 
 really a quality in the fire, of which the 
 proper name is heat ; and the name of heat 
 is given to this quality, both by philosophers 
 and by the vulgar, much more frequently than 
 to the sensation of heat. [242] This speech 
 of the philosopher, therefore, is meant by 
 liim in one sense ; it is taken by the vulgar 
 in another sense. In the sense in which 
 they take it, it is indeed absurd, and so 
 they hold it to be. In the sense in which 
 he means it, it is true ; and the vulgar, as 
 soon as they are made to understand that 
 sense, will acknowledge it to be true. They 
 know, as well as the philosopher, that the 
 fire does not feel heat : and this is all that 
 he means by saying there is no heat in the 
 fire.* 
 
 In the opinions of philosophers about 
 primary and secondary qualities, there have 
 been, as was before observed, several revo- 
 lutions.-!- They were distinguished, long be- 
 fore the days of Aristotle, by the sect called 
 Atomists : among whom Democritus made 
 a capital figure. In those times, the name 
 of qualily was applied only to those we call 
 secondary qualities ; the primary, being con- 
 sidered as essential to matter, were n^it 
 called qualities. J That the atoms, which 
 they held to be the first principles of things, 
 were extended, solid, figured, and movable, 
 there was no doubt ; but the question was, 
 whether they had smell, taste, and colour ? 
 or, as it was commonly expressed, whether 
 they had qualities ? The Atomists main- 
 tained, that they had not ; that the quali- 
 ties were not in bodies, but were something 
 resulting from the operation of bodies upon 
 our senses. § 
 
 * All this nrahiguity was understood and articu. 
 lately explai cd by former philns iphers. See above, 
 no'esat pp 20.i and 310, and Noe D.— H. 
 
 + See Note D — H. 
 
 X The Atomists derived the qualitative attributes 
 of.thiiigs from ihe quantitative — H. 
 
 ^ Slill Democritus suppose I certain real or ob- 
 jective tauscs t>r tlie subject ve differences of our 
 
 It would seem that, when men began to 
 speculate upon this subject, the primary 
 qualities appeared so clear and manifest 
 that they could entertain no doubt of their 
 existence wherever matter existed ; but the 
 secondary so obscure that they were at a 
 loss where to place them. They used this 
 comparison : as fire, which is neither in the 
 flint nor in the steel, is produced by their 
 collision, so those qualities, though not in 
 bodies, are produced by their impulse upon 
 our senses. [24.3] 
 
 This doctrine was opposed by- Aristotle.* 
 He believed taste and colour to be substan- 
 tial forms of bodies, and that their species, 
 as well as those of figure and motion, are 
 received by the senses. "I- 
 
 In believing that what we commonly 
 call taste and colour, is something really 
 inherent in body, and does not depend upon 
 its being tasted and seen, he followed nature. 
 But, in believing that our sensations of 
 taste and colour are the forms or species of 
 those qualities received by the senses, he 
 followed his own theory, which was an ab- 
 surd fiction. -f- Des Cartes not only shewed 
 the absurdity of sensible species received by 
 the senses, but gave a more just and more 
 intelligible account of secondary qualities 
 than had been given before. Mr Locke 
 followed him, and bestowed much pains 
 upon this subject. He was the first, I 
 think, that gave them the name of secondary 
 qualities,^ which has been very generally 
 adopted. He distinguished the sensation 
 from the quality in the body, which is the 
 cause or occasion of that sensation, and 
 shewed that there neither is nor can be any 
 similitude between them.§ 
 
 By this account, the senses are acquitted 
 of putting any fallacy upon us ; the sensation 
 is real, and no fallacy ; the quality in the 
 body, which is the cause or occasion of this 
 sensation, is likewise real, though the nature 
 of it is not manifest to our senses. If we 
 impose upon ourselves, by confounding the 
 sensation with the quality that occasions 
 it, this is owing to rash judgment or weak 
 understanding, but not to any false testi- 
 mony of our senses. 
 
 This account of secondary qualities I take 
 
 sensations Thus, in the different forms, positions, 
 and relations of atoms, he sought the ground or 
 difference of tastes, colours, heat and cold, &c. See 
 Theophrastus De Sensu, ^ 6S — Aristotle De Anima, 
 iii 2. — Galen De Ekmcntis — Simplicius in Phys. 
 Auscult.lihros.f. 119, b.— H. 
 
 * Aristotle admitted that the doctrine in question 
 was true, of colour, taste, &c , as aar' ivieynccv, but 
 not true of them as xark SiitKu.iv. See be Anima 
 iii. 2.— H. 
 
 t This is not really Aristotle's doctrine. — H. 
 
 t Locke only gave a new meaning to old terms. 
 The first and second or the primary anA secondary 
 qualities of Aristotle, denoted a distinction similar 
 to, but not identical with, that in question — H. 
 
 5 He distinguished nothing which had not been 
 more precisely discriminated by Aristotle and the 
 Cartesians. — H. 
 
 [942, 243]
 
 CHAP. XVII 
 
 •] 
 
 OF THE OBJECTS OF PERCEPTION. 
 
 317 
 
 to be very just ; and if Mr Locke liad 
 stopped here, he would have left the matter 
 very clear. But he thought it necessary to 
 introduce the theory of ideas, to explain the 
 distinction between primary and secondary 
 qualities, and by that means, as I think, 
 perplexed and darkened it. 
 
 When philosophers speak about ideas, we 
 are often at a loss to know what they mean 
 by them, and may be apt to suspect that 
 they are mere fictions, that have no exist- 
 ence. [244] They have told us, that, by the 
 ideas which we have immediately from our 
 senses, they mean our sensations.* These, 
 indeed, are real things, and not fictions. 
 We may, by accurate attention to them, 
 know perfectly their nature ; and, if philo- 
 sophers would keep by this meaning of the 
 word idea, when applied to the objects of 
 sense, they would at least be more intelli- 
 gible. Let us hear how Mr Locke explains 
 the nature of those ideas, when applied to 
 primary and secondary qualities. Book 2, 
 chap 8, § 7, tenth edition. " To discover 
 the nature of our ideas the better, and to 
 discourse of them intelligibly, it will be con- 
 venient to distinguish them, as they are 
 ideas, or perceptions in our minds, and as 
 they are modifications of matter in the bodies 
 that cause such perceptions in us, that so 
 we may not think (as perhaps usually is 
 done) that they are exactly the images and 
 resemblances of something inherent in the 
 subject ; most of those of sensation being, 
 in the mind, no more the likeness of some- 
 thing existing without us, than the names 
 that stand for them are the likeness of our 
 ideas, which yet, upon hearing, they are apt 
 to excite in us." 
 
 This way of distinguishing a thing, 77'/ s', 
 as wliat it is ; and, aecondl//, as what it is 
 not, is, I apprehend, a very extraordinary 
 way of discovering its nature.-f And if ideas 
 are ideas or perceptions in our inl;uls, and, 
 at the same time, the modifications of mut- 
 ter in the bodies that cause such ]iercep- 
 tions in us, it will be no easy matter to 
 discourse of them intelligibly. 
 
 Tlie discovery of the nature of ideas is 
 carried on in the next section, in a manner 
 no less extraordinary. '' Whatsoever the 
 mind perceives in itself, or is the inniiediate 
 object of perception, thought, or under- 
 standing, that I call idea ; and the power 
 to produce any idea in our mind, I call 
 quuiily of the subject wherein that power 
 is. Thus, a snowball having the power to 
 produce in us tlie ideas of white, cold, and 
 round — the powers to produce those ideas 
 
 • The Carfc«iaii!>, particularly Malibrnnchp, dis. 
 tinguiali' cl ilie Idea and the Fudiixj (si'iitiinfiil. siiisa. 
 lio.) Of I lie pWrnar// qualities in their doctririe we 
 have lili'as ; nl'thc srcoiulary , only l''c(lin;;s. — H. 
 
 t 'I his and soime of the follnwing Btricturen on 
 L,ockc arr>rather hyix'rcritical. — II. 
 
 [244-210] 
 
 in us, as they are in the snowball, I call 
 qualities ; and, as they are sensations, or 
 perceptions in our undei&taiulings, I call 
 them ideas ; which ideas, if 1 speak of 
 them sometimes as in the things themselves, 
 I would be understood to mean those quali- 
 ties in the objects which produce them in 
 us." [245] 
 
 These are the distinctions which Mr 
 Locke thought convenient, in order to dis- 
 cover the nature of our ideas of the quali- 
 ties of matter the better, and to discourse 
 of them intelligibly. I believe it will be 
 difficult to find two other paragraphs in the 
 essay so unintelligible. Whether this is to be 
 imputed to the intractable nature of ideas, 
 or to an oscitancy of the author, with which 
 he is very rarely chargeable, I leave the 
 reader to judge. There are, indeed, seve- 
 ral other passages in the same chapter, in 
 which a like obscurity appears ; but I do 
 not chuse to dwell upon them. The con- 
 clusion drawn by liim from the whole is, 
 that primary and secondary qualities are 
 distinguished by this, that the ideas of the 
 former are resemblances or copies of them, 
 but the ideas of the other are not resem- 
 blances of them. Upon this doctrine, I beg 
 leave to make two observations. 
 
 First, Taking it for granted that, by the 
 ideas of primary and secondary qualities, 
 he means the sensations" they excite in us, 
 I observe that it appears strange, that a 
 sensation should be the idea of a quality in 
 body, to which it is acknowledged to bear 
 no resemblance If the sensation of sound 
 be the idea of that vibration of the sound- 
 ing body which occasions it, a surfeit may, 
 for the same reason, be the idea of a feast. 
 
 A second observation is, that, when Mr 
 Locke affirms, that the ideas of primary 
 qualities — that is, the sensations* they raise 
 in us — are resemblances of those qualities, 
 he seems neither to have given due atten- 
 tion to those sensations, nor to the nature 
 of sensation in general. [24G] 
 
 Let a man press his hand against a hard 
 body, and let him attend to the sensation 
 he feels, excluding from his thought every 
 thing external, even the body that is the 
 cause of his feeling. This abstraction, in- 
 deed, is ditficult, and seems to have lieen 
 little, if at all practised. But it is not im- 
 possible, and it is evidently the only way to 
 understand tlie nature of the sensation. A 
 due attention to this sensation will satisfy 
 
 » Here, as formerly, {ride siii'ra, notes at pp 2nH, 
 Sim, Sec.,) lieid will in!.ii.t on Kivinn a more Iniiitid 
 meaning to the term Siiisation than I.oike dnl, and 
 on criticisihg him by that impnscd miaiiiiiK J he 
 Sensation of l.ockewai equivalent to \Ih' Sensation 
 iiiKl I'ereejition of Iteid. It is to he <)b-erved that 
 l.oeke ilid tint, like the rartesians, dll>tin^)Ul^h the 
 i.lea (coirispondinj; to lieid's l'ercr|.tioiO I'oni the 
 feeling (aeniiinent.sciu tin) corrciipoiidinB to Keld'» 
 SenBation.^Il,
 
 318 
 
 ON THE INTELLECTUAL POWERS. 
 
 [[essay u 
 
 him that it is no more like Iiardness in a 
 body tlian the sensation of sound is hke 
 vibration in the sounding body. 
 
 I know of no ideas but my conceptions ; 
 and my idea of hardness in a body, is the 
 conception of such a cohesion of its parts 
 as requires great force to disphice them. I 
 have both the conception and behef of this 
 quahty in the body, at the same time that 
 I have the sensation of pain, by pressing 
 my hand against it. The sensation and 
 perception are closely conjoined by my 
 constitution ; but I am sure they have no 
 similitude ; I know no reason why the one 
 should be called the idea of the other, which 
 does not lead us to call every natural effect 
 the idea of its cause. 
 
 Neither did Mr Locke give due attention 
 to the nature of sensation in general, when 
 he affirmed that the ideas of primary qua- 
 lities — that is, the sensations* excited 
 by them — are resemblances of those quali- 
 ties. 
 
 That there can be nothing like sensation 
 in an insentient being, or like thought in 
 an unthinking being, is self-evident, and 
 has been shewn, to the conviction of all 
 men that think, by Bishop Berkeley; yet 
 this was unknown to Mr Locke. It is an 
 humbling consideration, that, in subjects of 
 this kind, self-evident truths may be hid 
 from the eyes of the most ingenious men. 
 But we have, withal, this consolation, that, 
 when once discovered, they shine by their 
 own light : and that light can no more be 
 put out. [247] 
 
 Upon the whole, Mr Locke, in making 
 secondary qualities to be powers in bodies 
 to excite certain sensations in us, has given 
 a just and distinct analysis of what our 
 senses discover concerning them ; but, in 
 applying the theory of ideas to them and 
 to tlie primary qualities, he has been led to 
 saj' things that darken the subject, and that 
 will not bear examination, -f 
 
 Bishop Berkeley having adopted the sen- 
 timents common to philosophers, concern- 
 ing the ideas we have by our senses — to wit, 
 that they are all sensations — saw more clearly 
 tlie necessary consequence of this doctrine; 
 which is, that there is no material world — 
 no qualities primary or secondary — and, 
 consequently, no foundation for any dis- 
 tinction between them.:|: He exposed the 
 absurdity of a resemblance between our 
 
 • No ; not S^ensations in Reid's meaning ; but Per- 
 cepts — the immcdiiite objects we are conscious of in 
 the cognitions of sense.— H. 
 
 1 The Cartesians did no' apply the term ideas to 
 our sensations of tlie secondary qualities. — H. 
 
 X See above, p. l-t'^, note *. I'tie mere distinction 
 of primary and secmdary qualities, of perception Miid 
 sensation, is of no importance against Idealism, if the 
 primary qualities as immediately perce'ved. {i e. as 
 known t" coiiscinusness,) be only conceptions, no- 
 tions, or modit:cations o( miijd itselt. See following 
 Note.— a 
 
 sensations and any quality, primary or 
 secondary, of a substance that is supposed 
 to be insentient. Indeed, if it is granted 
 that the senses have no other office but to 
 furnish us with sensations, it will be found 
 impossible to make any distinction between 
 priinary and secondary qualities, or even to 
 maintain the existence of a material world. 
 From the account I have given of the 
 various revolutions in the opinioris of philo- 
 sophers about primary and secondary qua- 
 lities, I think it appears that all the dark- 
 ness and intricacy that thinking men have 
 found in this subject, and the errors they 
 have fallen into, have been owing to the 
 difficulty of distinguishing clearly sensa- 
 tion from perception — what we feel from 
 what we perceive. 
 
 The external senses have a double pro- 
 vince — to make us feel, and to make us 
 perceive. They furnish us with a variety 
 of sensations, some pleasant, others painful, 
 and others indifferent ; at the same tinie, 
 they give us a conception and an invincible 
 belief of the existence of external objects. 
 This conception of external objects is the 
 work of nature. The belief of their exist- 
 ence, which our senses give, is the work of 
 nature ; so likewise is the sen-sation that 
 accompanies it. This conception and be- 
 lief which nature produces by means of the 
 senses, we call perception.' [248] The 
 feeling which goes along with the percep- 
 tion, we call sensation. The perception and 
 its corresponding sensation are produced at 
 the same time. In our experience we never 
 find them disjoined. Hence, we are led to 
 consider them as one thing, to give them 
 one name, and to confound their different 
 attributes. It becomes very difficult to 
 separate them in thought, to attend to each 
 by itself, and to attribute nothing to it 
 which belongs to the other. 
 
 To do this, requires a degree of attention 
 to what passes in our own minds, and a 
 talent of distinguishing things that differ, 
 which is not to be expected in the vulgar, 
 and is even rarely found in philosophers ; 
 so that the progress made in a just analysis 
 of the operations of our senses has been 
 very slew. The hypothesis of ideas, so 
 generally adopted, hath, as I apprehend, 
 greatly retarded this progress, and we might 
 hope for a quicker advance, if philosophers 
 could so far humble themselves as to be- 
 lieve that, in every branch of the philosophy 
 of nature, the productions of human fancy 
 and conjecture will be found to be dross ; 
 and that the only pure metal that will en. 
 dure the test, is what is discovered by 
 patient observation and chaste induction. 
 
 * If the conception, like the belief, be subjectUe 
 in perception, we have no refuge. from Idealism in 
 this ddctrine. See above, tlie notes at )'p. liS-ISO, 
 I8:{, tic, and Note C. — H. 
 
 [247, 248]
 
 CHAP. XVIII.] OF OTHER OBJECTS OF PERCEPTION. 
 
 319 
 
 CHAPTER XVIII. 
 
 OF OTHER OBJECTS OF PERCEPTION. 
 
 Besides primary and secondary qualities 
 of bodies, there are many other immediate 
 objects of perception. Without pretending 
 to a complete enumeration, I think they 
 mostly fall under one or other of the follow- 
 ing, classes. 1st, Certain states or condi- 
 tions of our own bodies. 2d, Mechanical 
 powers or forces. 3c/, Chemical powers. 
 4lh, Medical powers of virtues, dtli. Vege- 
 table and animal powers. [249] 
 
 That we perceive certain disorders in our 
 own bodies by means of uneasy sensations, 
 which nature hath conjoined with them, will 
 not be disputed. Of this kind are toothache, 
 headache, gout, and every distemper and 
 hurt which we feel. The notions which 
 our sense gives of these, have a strong 
 analogy to our notions of secondary qualities. 
 Both are similarly compounded, and may 
 be similarly resolved, and they give light to 
 each other. 
 
 In the toothache, for instance, there is, 
 first,, a painful feeling ; and, secondly, a 
 conception and belief of some disorder in 
 the tooth, which is believed to be the cause 
 of the uneasy feeling.* The first of these 
 is a sensation, the second is perception ; 
 for it includes a conception and belief of an 
 external object. But these two things, 
 though of different natures, are so con- 
 stantly conjoined in our experience and in 
 our imagination, that we consider them as 
 one. We give the same name to both ; for 
 the toothache is the proper name of the 
 pain we feel ; and it is the proper name of 
 the disorder in the tooth which causes that 
 pain. If it should be made a question 
 T.hether the toothache be in the mind that 
 'eels it, or in the tooth that is aft'i cted, 
 much might fee said on both sides, while it 
 is not observed that the word has two mean- 
 ings. -j- But a little reflection satisfies us, 
 that the pain is in the mind, and the dis- 
 order in the tooth. If some pliilosophcr 
 should pretend to have made the discovery 
 tliat the toothache, the gout, the headaclie, 
 are only sensations in the mind, and that 
 it is a vulgar error to conceive that they 
 are di.stempers of the body, he might defend 
 his system in the same manner as tho.se 
 wlio affirm that there is no sound, nor 
 colour, nor taste in bodies, defend that para- 
 dox. But both these systems, like most 
 
 * There is no such perception, properly so called. 
 The cogriitiriri is merely an inference Uim the 
 feelinK; and its>ohjcct, at least, only some hjpothc- 
 tical rtprr sentation o( a really i'ltiutum quid. Here 
 the «ul)je<;tive element pre|i(jnderatc» i>o greatly as 
 almoht to extinKuiih tlie objective — 1 1. 
 
 t Thin id not correct. .See rtljo»e, p. 2' 5, cnl. b 
 note *,aiid Sote ().— H. 
 
 [2i9, 2.00]] 
 
 paradoxes, will be found to be only an abuse 
 of words. 
 
 We say that we feci the toothache, not 
 that we perceive it. On the other hand, w«3 
 say that we perceive the colour of a body, 
 not that we feel it. Can any reason be given 
 for this difference of phraseology ? [250] 
 In answer to this question, I apprehend 
 that, both when we feel the toothache and 
 when we see a coloured body, there is sensa- 
 tion and perception conjoined. But, in the 
 toothache, the sensation being very painful, 
 engrosses the attention ; and therefore we 
 speak of it as if it were felt only, and not 
 perceived : whereas, in seeing a coloured 
 body, the sensation is indifferent, and draws 
 no attention. The quality in the body, 
 which we call its colour, is the only object 
 of attention ; and therefore we speak of it 
 as if it were perceived and not felt. Though 
 all philosophers agree that, in seeing colour 
 there is sensation, it is not easy to persuade 
 the vulgar that, in seeing a coloured body, 
 when the light is not too strong nor the 
 eye inflamed, they have any sensation or 
 feeling at all. 
 
 There are some sensations, which, though 
 they are very often felt, are never attended 
 to, nor reflected upon. We have no con- 
 ception of them ; and, therefore, in language 
 there is neither any name for them, nor 
 any form of speech that supposes their 
 existence. Such are the sensations of colour, 
 and of all primary qualities ; and, therefore, 
 those qualities are said to be perceived, but 
 not to be felt. Taste and smell, and heat 
 and cold, have sensations that are often 
 agreeable or disagreeable, in such a degree 
 as to draw our attention ; and they are 
 .sometimes said to be felt, and sometimes to 
 be perceived. When disorders of the body 
 occasion very acute pain, the unea-sy sensa- 
 ation engrosses the attention, and they are 
 said to be felt, not to be perceived." 
 
 There is amithor question relating to 
 phraseology, which this subject suggests. 
 A man says, he feels ])ain in such a parti- 
 cular part of his body ; in his toe for in- 
 stance. Now, reason assures us that pain 
 being a sensation, can only be in the sen- 
 tient being, as its subject — that is, in the 
 mind. And, thdugli philosophers have dis- 
 puted much al)out the place of the mind ; 
 yet none of them ever placed it in the toe.-j- 
 
 • As already repeatedly oliscrved, the objective 
 element (perception) and the eubjiciive element 
 (IceliiiK, sensation) are always in tne inver>e ratio 
 of each other. 'I'his is a law of which Keid and the 
 philosophers were not aware — U. 
 
 t Not In the loe r.n7».v/r.V// lint, both in ancient 
 and modern times, the ri|iiiiion has bi'in lielil that 
 the mind h.is .is nuich a lix-d prisenie in I he toe ns in 
 the head, 1 he doctrine, indi'cil.JonK (,'i'"''r''"y "'•'i'l- 
 laiiird was, that in relation to [he lindy, Ilii-Sdiiris nil 
 
 ill llii'vlidlr, mill III! ill i-irrii purl. On llu' ipicsli f 
 
 the seat of the soul, which h;ik hern m.irvdiousljr 
 perplexed, 1 cmntit iTiter. 1 shall only say, in (lene- 
 ral, Iha' thr »ir»t condition of the possibility ol an
 
 320 
 
 ON THE INTELLECTUAL POWERS. 
 
 [essay n. 
 
 What shall we say then in this case ? Do 
 our senses really deceive us, and make us 
 believe a thing which our reason determines 
 to be impos.sihle ? [251] I answer, ^'rs^, 
 That, when a man says he has pain in his toe, 
 he is perfectly understood, both by himself 
 and those who hear him. This is all that 
 lie intends. lie really feels what he and 
 all men call a pain in the toe ; and there is 
 no deception in the matter. Whether, 
 therefore, there be any impropriety in the 
 phrase or not, is of no consequence in com- 
 mon life. It answers all the ends of speech, 
 both to the speaker and the hearers. 
 
 In all languages there are phrases which 
 have a distinct meaning ; while, at the 
 same time, there may be something in the 
 structure of them that disagrees with the 
 analogy of grammar or with the principles 
 of philosophy. And the reason is, because 
 language is not made either by gramma- 
 rians or philosophers. Thus, we speak of 
 feeling pain, as if pain was something dis- 
 tinct from the feeling of it. We speak of 
 pain coming and goin^g, and removing from 
 one place to another. Such phrases are 
 meant by those who use them in a sense 
 that is neither obscure nor false. But the 
 philosopher puts them into his alembic, 
 reduces them to their first principles, draws 
 out of them a sense that was never meant, 
 and so imagines that he has discovered an 
 erx'or of the vulgar. 
 
 I observe, secondly, That, when we con- 
 sider the sensation of pain by itself, with- 
 out any respect to its cause, we cannot say. 
 with propriety, that the toe is either the 
 place or the subject of it. But it ought to 
 be remembered, that, when we speak of pain 
 in the toe, the sensation is combined in our 
 thought, with the cause of it, which really is 
 in the toe. The cause and the effect are 
 combined in one complex notion, and the 
 same name serves for both. It is the busi- 
 ness of the philosopher to analyse this com- 
 ])!ex notion, and to give different names to 
 its different ingredients. He gives the 
 name oi' p'lin to the sensation only, and the 
 name of disorder to the unknown cause of 
 it. Then it is evident that the disorder 
 only is in the toe, and that it would be an 
 error to think that the pain is in it." But 
 we ought not to ascribe this error to the 
 vulgar, who never made the distinction, and 
 who, under the name of pain, comprehend 
 both the sensation and its cause. -j- [252] 
 
 immeiiiate, iniuitivo, or real perception of external 
 thiiig<, wh fh iiur consciousne.-s a'isures that we pos- 
 Si s-i, is the immediate conrieciion ot the cognitive 
 principle with every part of the corporeal orgaiiisin. — 
 
 * Only if the toe he consiflered as a mere material 
 mass, anil apart Irom an animating principle. — H. 
 
 t I'hat the pain is where it is felt is, however, the 
 doctrine ol common sense. We only feel in as much 
 as we have a horty ami a soul ; we only feel pain in 
 the toe in as much as we have such a member, and in 
 
 Cases sometimes happen, which giva 
 occasion even to the vulgar to distinguish 
 the painful sensation from the disorder 
 which is the cause of it. A man who has had 
 his leg cut off, many years after feels pain 
 in a toe of that leg. The toe has now no 
 existence ; and he perceives easily, that the 
 toe can neither be the place nor the subject 
 of the pain which he feels ; yet it is the 
 same feeling he used to have from a hurt 
 in the toe ; and, if he did not know that his 
 leg was cut off, it would give him the same 
 immediate conviction of some hurt or dis- 
 order in the toe.* 
 
 The same phenomenon may lead tho 
 philosopher, in all cases, to distinguish sens- 
 ation from perception. We say, that the 
 man had a deceitful feeling, when he felt a 
 pain in his toe after the leg was cut off; 
 and we have a true meaning in saying so. 
 But, if we will speak accurately, our sensa- 
 tions cannot be deceitful ; they must be 
 what we feel them to be, and can be no- 
 thing else. Where, then, lies the deceit ? I 
 answer, it lies not in the sensation, which 
 is real, but in the seeming perception he 
 had of a disorder in his toe. This percep- 
 tion, which Nature had conjoined with the 
 sensation, was, in this instance, fallacious. 
 
 The same reasoning may be applied to 
 every phenomenon that can, with propriety, 
 be called a deception of sense. As when 
 one who has the jaundice sees a body 
 yellow, which is really white ;-|- or when a 
 man sees an object double, because his 
 eyes are not both directed to it : in these, 
 and other like cases, the sensations we have 
 are real, and the deception is only in the 
 perception which nature has annexed to 
 them. 
 
 Nature has connected our perception of 
 external objects with certain sensations. 
 If the sensation is produced, the corre- 
 sponding perception follows even when there 
 is no object, and in that case is apt to 
 deceive us. [253] In like manner, nature 
 has connected our sensations with certain 
 impressions that are made upon the nerves 
 and brain ; and, when the imjiression is 
 made, from whatever cause, the corre- 
 sponding sensation and perception imme- 
 diately follow. Thus, in the man who feels 
 pain in his toe after the leg is cut off, the 
 nerve that went to the toe, part of which was 
 cut off with the leg, had the same impres- 
 sion made upon the remaining part, which, 
 in the natural state of his body, was caused 
 
 a< much as the mind, or sentient principle, pervade3 
 it. We just as much feel in the toe as we think in 
 in the head. If (but only if) the latter be a vitium 
 subreplionis, as Kant thinks, so is the former. — H. 
 
 * J his illustration is Des Cartes'. It correct, it 
 only shews that the connection of mind with organ, 
 ization extends from the centre to the circumference 
 of the nervous system, and is not limited to any 
 px-t.— H. 
 
 I 1 he man docs not S"e the white hod)/ at all.— H. 
 
 [251-253]
 
 CHAP, xvni.] or OTHKIl OBJPXTS OF PERCEPTION. 
 
 B21 
 
 by a liurt in tlie toe : and immediately this 
 iuipressiou is followed by the sensation and 
 percejttion which nature connected with it. • 
 
 In like manner, if the same impressions 
 which are made at present upon my optic 
 nerves by the objects before me, could be 
 made in the dark, I apprehend that I 
 should have the same sensations and see 
 the same objects which I now see. The im- 
 pressions and sens.itions would in such a case 
 be real, and the perception only iallacious.* 
 
 Let us next consider the notions which 
 our senses give us of those attributes of 
 bodies called powers. This is the more 
 necessary, because power seems to imjily 
 some activity ; yet we consider body as a 
 dead inactive thing, which does not act, but 
 may be acted upon. 
 
 Of the mechanical powers ascribed to 
 bodies, that which is called their rv's insila 
 or inertia, may first be considered. By 
 this is meant, no more than that bodies 
 never change their state of themselves, 
 either from rest to motion, or from motion 
 to rest, or from one degree of velocity or 
 one direction to another. In order to 
 produce any such change, there must be 
 some force impressed upon them ; and the 
 change produced is precisely proportioned 
 to the force impressed, and in the direction 
 of that force. 
 
 That all bodies have this property, is a 
 matter of fact, which we learn from daily 
 observation, as well as from the most accu- 
 rate experiments.. [254] Now, it seems 
 plain, that this does not imply any activity 
 in body, but rather the contrary. A power 
 in body to change its state, would much 
 rather imply activity than its continuing in 
 the same state : so that, although this 
 property of bodies is called their vis insita, 
 or vis irifrtia; it implies no proper activity. 
 
 If we consider, next, the power of gravity, 
 it is a fact that all the bodies of our pla- 
 netary system gravitate towards each other. 
 This has been fully proved by the great 
 Newton. But this gravitation is not con- 
 ceived by that philosoplier to be a power 
 inherent in bodies, which they exert of 
 themselves, but a force impressed upon 
 them, to which they must necessarily yield. 
 Whether this force be impressed by some 
 subtile tether, or whether it be impressed by 
 the ])OW(.-r of the Supreme Being, or of some 
 subordinate sjilrituul being, we do not know; 
 but all sound natural philosophy, particu- 
 larly tliHt of Newton, sii]ii)oses it to be an 
 impresseil force, and not inherent in bodies. -f- 
 
 Ho that, when bodies gravitate, they do 
 
 • 'Ihis i« a I'octrine which cannot bo lecnncilcd 
 with tliat (.f an intuitive or oljji'ctivo pcrcciitioti. 
 All hpre is Ruljji.ctive H. 
 
 t 'I'hat .ill firlivili/ mpposps an iiiiiii/tfrrinl or spi. 
 riliuil ancnt, is an aiiricnt doctiini-. It is, however, 
 only an hvpoihesis.— H. 
 
 not properly act, but are acted upon : they 
 only yield to an impression that is made 
 upon them. It is common in language to 
 express, by active verbs, many changes in 
 things wherein they are meroly passive : 
 and this way of speaking is used chiefly 
 when the cause of the change is not obvious 
 to sense. Thus we say tliat a ship s.'wls 
 when every man of common sense knows 
 that she has no inherent power of motion 
 and is only driven by wind and tide. In 
 like manner, when we say that the planets 
 gravitate to^^•ards the siui, we mean no more 
 but that, by some unknown power, they are 
 drawn or impelled in that direction. 
 
 What has been said of the power of gra- 
 vitation may be applied to other mechanical 
 powers, such as cohesion, magnetism, elec- 
 tuicity ; and no less to chemical and medical 
 powers. By all these, certain effects are 
 produced, upon the application of one body 
 to another. [255] Our senses discover the 
 effect; but the power is latent. We know 
 there must be a cause of the effect, and we 
 form a relative notion of it from its effect ; and 
 very often the same name is used to signify 
 the unknown cause, and the known effect. 
 
 We ascribe to vegetables the powers of 
 drawing nourishment, growing and nmlti- 
 plying their kind. Here likewise the effect 
 is manifest, but the cause is latent to sense. 
 These powers, therefore, as well as all the 
 other powers we ascribe to bodies, are un- 
 known causes of certain known effects. It 
 is the business of philosophy to in\csti<Tate 
 the nature of those powers as far as we are 
 able ; but our senses leave us in the dark. 
 
 We may observe a great similarity in the 
 notions which our senses give us of second- 
 ary qualities, of the disorders we feel in our 
 own bodies, and of the various powers of 
 bodies which we have enumerated. They 
 are all obscure and relative notions, being 
 a conception of some unknown cause of a 
 known effect. Their names are, for the 
 most part, common to the effect and to 
 its cause ; and they are a jiroper subject 
 of philosophical disquisition. They might, 
 therefore, I think, not iinpioperly be called 
 vcciill qualities. 
 
 This name, indeed, is fallen into disgrace 
 since the time of Des Cartes. It is saiil to 
 have been used by the Peripatetics to cloak 
 their ignorance, and to stop all inquiry into 
 the nature of those qualities called orrull. 
 Be it so. Let those answer f )r this abuse 
 of the word who were guilty of it. To call a 
 thing occult, if we attend to the meaning 
 of the word, is rather modestly to confess 
 ignorance, than to cloak it. It is to point 
 it out as a ])ropor subject fur the investiga- 
 tion of jdiiloHophi'rs, whose | roper liusiness 
 it is to licttcr the condition of humanity, liy 
 discovering what w;is IjiTure liiil from human 
 knowli'dge. [25(i] 
 
 V
 
 322 
 
 ON THE INTELLECTUAL POWERS. 
 
 [essay ir. 
 
 Were I therefore to make a division of 
 the qualities of bodies as they appear to our 
 senses, I would divide them first into those 
 that are manifest and those that are occulf. 
 The manifest qualities are those which Mr 
 Locke calls primary ; such as Extension, 
 Fijjure, Divisibility, Motion, Hardness, 
 Softness, Fluidity. The nature of these is 
 manifest even to sense ; and the business of 
 the philosopher with regard to them, is not 
 to find out their nature, which is well known, 
 but to discover the effects produced by their 
 various combinations ; and, with regard to 
 those of them which are not essential to 
 matter, to discover their causes as far as 
 he is able. 
 
 The second class consists of occult quali- 
 ties, which may be subdivided into various 
 kinds : as, first, the secondary qualities ; 
 secondlu, the disorders we feel in our own 
 bodies; and, thirdly, all the qualities which 
 we call powers of bodies, whether mechani- 
 cal, chemical, medical, animal, or vegetable ; 
 or if there be any other powers not compre- 
 hended under these heads. Of all these the 
 existence is manifest to sense, but the nature 
 is occult ; and here the philosopher has an 
 ample field. 
 
 What is necessary for the conduct of our 
 animal life, the bountiful Author of Nature 
 hath made manifest to all men. But there 
 are many other choice secrets of Nature, 
 the discovery of which enlarges the power 
 and exalts the state of man- These are left 
 to be discovered by the proper use of our 
 rational powers. They are hid, not that 
 they may be always concealed from human 
 knowledge, but that we may be excited to 
 search for them. This is the proper busi- 
 ness of a philosopher, and it is the glory of 
 a man, and the best reward of his labour, 
 to discover what Nature has thus con- 
 cealed. [257 J 
 
 CHAPTER XIX. 
 
 OF MATTER AND OF SPACE. 
 
 The objects of sense we have hitherto 
 considered are qualities. But qualities must 
 have a subject. We give the names of 
 matter, material substance, and hodij, to the 
 subject of sensible qualities ; and it may be 
 asked what this matler is. 
 
 I perceive in a billiard ball, figure, colour, 
 and motion ; but the ball is not figure, nor 
 is it colour, nor motion, nor all these taken 
 together -, it is something that has figure, 
 and colour, and motion. This is a dictate 
 of nature, and the belief of all mankind. 
 
 As to the nature of this something, I am 
 afraid we can give little account of it, but 
 that it has the qualities which our senses 
 discover. 
 
 But how do we know that they are qua- 
 lities, and cannot exist without a subject ? 
 I confess I cannot explain how we know 
 that they cannot exist without a subject, 
 any more than I can explain how we know 
 that they exist. We have the information 
 of nature for their existence ; and I think 
 we have the information of nature that they 
 are qualities. 
 
 The belief that figure, motion, and colour 
 are qualities, and require a subject, must 
 either be a judgment of nature, or it must 
 be discovered by reason, or it must be a 
 prejudice that has no just foundation. There 
 are philosophers who maintain that it is a 
 mere prejudice ; that a body is nothing but 
 a collection of what we call sensible quali- 
 ties ; and that they neither have nor need 
 any subject. This is the opinion of Bishop 
 Berkeley and Mr Hume; and they were 
 led to it by finding that they had not in 
 their minds any idea of substance. [258] 
 It could neither be an idea of sensation nor 
 of reflection. 
 
 But to me nothing seems more absurd 
 than that there should be extension without 
 anything extended, or motion without any- 
 thing moved ; yet I cannot give reasons for 
 my opinion, because it seems to me self- 
 evident, and an immediate dictate of my 
 nature. 
 
 And that it is the belief of all mankind, 
 appears in the structure of all languages ; 
 in which we find adjective nouns used to 
 express sensible qualities. It is well known 
 that everyadjective in language must belong 
 to some substantive expressed or under- 
 stood — that is, every quality nmst belong 
 to some subject. 
 
 Sensible qualities make so great apart of 
 the furniture of our minds, their kinds are 
 so many, and their number so great, that, 
 if prejudice, and not nature, teach us to 
 ascribe them all to a subject, it must have 
 a great work to perform, which cannot be 
 accomplished in a short time, nor carried 
 on to the same pitch in every individual. 
 We should find not individuals only, but 
 nations and ages, differing from each other 
 in the progress which this prejudice had 
 made in their sentiments ; but we find no 
 such difference among men. What one man 
 accounts a quality, all men do, and ever did. 
 
 It seems, therefore, to be a judgment of 
 nature, that the things immediately per- 
 ceived are qualities, which must belong to 
 a subject ; and all the information that our 
 senses give us about this subject, is, that 
 it is that to which such qualities belong. 
 From this it is evident, that our notion of 
 body or matter, as distinguished from its 
 qualities, is a relative notion;" and I am 
 
 * 'Jhat is— our notion of absolute body is relative. 
 This is incorrectly expressed. \Vc tan know, we can 
 
 [257. y58]
 
 CHAP. XIX. 
 
 OF MATTER AND OF SPACE. 
 
 323 
 
 afraid it nmst always 1 e oliscure until int'ii 
 have other faculties. [259] 
 
 Ti.e [ihilosopher, in this, seems to have 
 n > advantage above the vulgar ; for, as 
 they pcvrceive colour, and figure, and motion 
 b.. tlieir senses as well he does, and both 
 are equally certain that there is a subject 
 of those qualities, so the notions which 
 both have of this subject are equally ob- 
 scure. When the philosopher calls it a 
 substratum, and a subject of inhesion, those 
 learned words convey no meaning but what 
 every man understands and expresses, by 
 saying, in conmion language, that it is a 
 thing extended, and solid, and movable. 
 
 The relation which sensible qualities bear 
 to their subject — that is, to body — is not, 
 liowever, so dark but that it is easily dis- 
 tinguished from all other relations. Every 
 man can distinguisli it from the relation 
 of an effect to its cause ; of a mean to its 
 end ; or of a c-ign to the thing signified by 
 it. 
 
 I think it requires some ripeness of un- 
 derstanding to distinguish the qualities of a 
 body from the body. Perhaps this dis- 
 tinction is not made by brutes, nor by in- 
 fants ; and if any one thinks that this dis- 
 tinction is not made by our senses, but by 
 some other power of the mind, I will not 
 dispute this point, provided it be granted 
 that men, when their faculties are ripe, 
 have a natural conviction that sensible qua- 
 lities cannot exist by themselves without 
 some subject to which they belong. 
 
 I think, indeed, that some of the determ- 
 inations we form concerning matter can- 
 not be deduced solely from the testimony 
 of sense, but must be referred to some other 
 source. 
 
 There seems to be nothing more evident 
 than that all bodies must consist of parts ; 
 and that every part of a body is a body, and 
 a distinct being, which may exist without the 
 other parts ; and yet I apprehend tliis con- 
 clusion is not deduced solely from the testi- 
 mony of sense : for, besides that it is a 
 necessary truth, and, therefore, no object 
 of sense,* there is a limit beyond which we 
 
 conceive, only what is rflativc. Our knowledge of 
 qualities OT }iJice)io!>icna is necessarily relative; for 
 these exist only as tliey exist iniTlation to our/aciil- 
 ties. 'I'lie knowledge, or even the conception, of a 
 subhtauce in iiselt', anil a|iart from any qualities in 
 relatinii to, and thirelore cognisal>lc or conceivable 
 by, our minds, involves a contradiction. Of such we 
 can form only a nrr/ative notion ; that is, we cm 
 merely eonccive it us iiicoticeivahte. Hut to call this ne- 
 gative notion a reluliri: itoliim, is wrong ; 1", because 
 ail cur (positive) notions are relative; and 2", because 
 this is itselfa negative notion — i. c, no notion at all — 
 sill. ply because there is no relation. 'Ihe same im- 
 propi r application of the term relative was also made 
 by Held uhen siicaking ol the secondary qualities. — II. 
 * It is creditiibic to He.d that ho iicrceived th.it 
 the qu.<lity of in'cessil;/ iy the criterion which distm. 
 gui-het native Iroin oiliailitiotis notiims <.r judg. 
 men's. Heuid noi, however, alwaysmakethe proper 
 use of It. Leibnitz h;is the honour of first ixplicitly 
 enouncing this criterion, and Kant of first fiilU np- 
 
 L^.w-yfjij 
 
 cannot perct-ive any division of a body. 
 The parts become too small to be perceived 
 by our senses; but we cannot believe that 
 it becomes then incapable of being farther 
 divided, or that such division would make 
 it not to be a body. [200] 
 
 We carry on the division and subdivision 
 in our thought far beyond the reach of our 
 senses, and we can find no end to it : nay, 
 I think we plainly discern that there can 
 be no limit beyond which the division can- 
 not be carried. 
 
 For, if there be any limit to this division, 
 one of two things must necessarily happen : 
 either we have come by division to a body 
 which is extended, but has no parts, and is 
 absolutely indivisible ; or this body is divi- 
 sible, but, as soon as it is divided, it becomes 
 no body. Both these positions seem to me 
 absurd, and one or the other is the neces- 
 sary consequence of supposing a limit to the 
 divisibility of matter. 
 
 On the other hand, if it is admitted that 
 the divisibility of matter has no limit, it 
 will follow that no body can be called one 
 individual substance. You may as well 
 call it two, or twenty, or two hundred. For, 
 when it is divided into parts, every part is 
 a being or substance distinct from all the 
 other parts, and was so even before the di- 
 vision. Any one part may continue to 
 exist, though all the other parts were an- 
 nihilated. 
 
 There is, indeed, a principle long re- 
 ceived as an axiom in metaphysics, which 
 I cannot reconcile to the divisibility of mat- 
 ter ; it is, that every being is one, omne etis 
 est nnitm. By which, I suppose, is meant, 
 that everything that exists must either be 
 one indivisible being, or composed of a de- 
 terminate number of indivisible beings. 
 Thus, an army may be divided into regi- 
 ments, a regiment into companies, and a 
 company into men. But here the division 
 has its limit ; for you cannot divide a man 
 without destroying him, because he is an 
 individual ; and everything, according to 
 this axiom, must be an individual, or made 
 up of individuals. [201 ] 
 
 That this axiom will hold with regard to 
 an army, .•iiid with regard to many other 
 things, must be granted ; but I rc(juire the 
 evidence of its being applicable to all beings 
 whatsoever. 
 
 Leibnitz, conceiving that all beings must 
 have this metaphysical unity, was liy this 
 led to maintain that matter, and, indeed, 
 the whole uni/ersc, is made up of monads — 
 that is, simple and indivisible substances. 
 
 Pcrhap.s, the same apprehension miglit 
 lead Bofjcovich into his hypothesis, which 
 seems nnieh more ingenious — to wit, that 
 
 plying it to the phienoineriR. In none haii Kunt licen 
 
 more suiTcs-fiil than in this uiuier consideration. — 
 II
 
 324 
 
 ON THE INTELLECTUAL POWERS. 
 
 [kSSAY II. 
 
 matter is composed of a definite number of 
 mathematical points, endowed with certain 
 powers of attraction and repulsion. 
 
 The divisibility of matter without any 
 limit, seems to me more tenable than either 
 of these hypotheses ; nor do I lay much 
 stress upon the metaphysical axiom, con- 
 sidering its origin. IMetaphysicians thought 
 proper to make the attributes common to 
 all beings the subject of a science. It 
 must be a matter of some difficulty to find 
 out such attributes ; and, after r.acking 
 their invention, they have specified three — 
 to wit. Unity, Verity, and Goodness ; and 
 these, I suppose, have been invented to 
 make a number, rather than from any clear 
 evidence of their being universal. 
 
 There are other determinations concern- 
 ing matter, wliich, I think, are not solely 
 founded upon the testimony of sense : such 
 as, that it is impossible that two bodies 
 should occupy the same place at the same 
 time ; or that the same body should be in 
 different places at the same time ; or that 
 a body can be moved from one place to 
 another, without passing through the inter- 
 mediate places, either in a straight course, 
 or by some circuit. These appear to be 
 necessary truths, and therefore cannot be 
 conclusions of our senses ; for our senses 
 testify only what is, and not what must ne- 
 cessarily he.' [262] 
 
 We are next to consider our notion of 
 Space. It may be observed that, although 
 space be not perceived by any of our senses 
 when all matter is removed, yet, when we 
 perceive any of the primary qualities, space 
 presents itself as a necessary concomitant ;-f 
 for there can neither be extension nor mo- 
 tion, nor figure nor division, nor cohesion 
 of parts, without space. 
 
 There are only two of our senses by which 
 the notion of space enters into the mind — 
 to wit, touch and sight. If we suppose a 
 man to have neither of these senses, I do 
 not see how he could ever have any concep- 
 tion of space.* Supposing him to have 
 both, until he sees or feels other olijects, 
 he can have no notion of space. It has 
 neither colour nor figure to make it an 
 object of sight : it has no tangible quality 
 to make it an object of touch. But other 
 objects of sight and touch carry the notion 
 of space along with them ; and not the 
 notion only, but the belief of it ; for a body 
 could not exist if there was no space to con- 
 tain it. It could not move if there was 
 no space. Its situation, its distance, and 
 every relation it has to other bodies, suppose 
 space. 
 
 But, though the notion of space seems 
 
 * See last note.~H. 
 t See above, p. 12+, note f. — H. 
 i Vide supra, p. 123, col. b, notes *, t ; and p. 
 \26, col b, note*.— H. 
 
 not to enter, at first, into tlie mind, until it 
 is introduced by the proper objects of sense, 
 yet, being once introduced, it remains in 
 our conception and belief, though the objects 
 which introduced it be removed. We see 
 no absurdity in supposing a body to be an- 
 nihilated ; but the space that contained it 
 remains ; and, to suppose that annihilated, 
 seems to be absurd. It is so much allied 
 to nothing or emptiness, that it seems in- 
 capable of annihilation or of creation.* 
 
 Space not only retains a firm hold of our 
 belief, even when we suppose all the objects 
 that introduced it to be annihilated, but it 
 swells to immensity. We can set no limits 
 to it, either of extent or of duration. Hence 
 we call it immense, eternal, immovable, 
 and indestructible. But it is only an im- 
 mense, eternal, immovable, and indestruc- 
 tible void or emptiness. Perhaps we may 
 apply to it what the Peripatetics said of 
 their first matter, that, whatever it is, it is 
 potentially only, not actu.ally. [26.3] 
 
 When we consider parts of space that 
 have measure and figure, there is nothing 
 we understand better, nothing about which 
 we can reason so clearly, and to so great 
 extent. Extension and figure are circum- 
 scribed parts of space, and are the object of 
 geometry, a science in which human reason 
 has the most ample field, and can go deeper, 
 and with more certainty, than in any other. 
 But, when we attempt to comprehend the 
 whole of space, and to trace it to its origin, 
 we lose ourselves in the search. The pro- 
 found speculations of ingenious men upon 
 this subject differ so widely as may lead 
 us to suspect that the line of human under- 
 standing is too short to reach the bottom 
 of it. 
 
 Bishop Berkeley, I think, was the first 
 who observed that the extension, figure, and 
 space, of which we speak in common lan- 
 guage, and of which geometry treats, are 
 originally perceived by the sense of touch 
 only ; but that there is a notion of exten- 
 sion, figure, and space, which may be got 
 by sight, without any aid from touch. To 
 distinguish these, he calls the first tangible 
 extension, tangible figure, and tangible 
 space. Tlie last he calls visible. 
 
 As I think this distinction very import- 
 ant in the philosophy of our senses, I shall 
 adopt the names used by the inventor to 
 express it ; remembering what has been 
 already observed — that space, whether tan- 
 gible or visible, is not so properly an object 
 of sense, as a necessary concomitant of the 
 objects both of sight and touch. -f- 
 
 * His doctrine of space is an example of Reid'3 
 imperfect application of the criterion of ncces^ity. 
 Seep. 123, note t It seeminply required but littltto 
 rise to Kant's view of the conception of space, ae an 
 a priori or native form of thought, — H. 
 
 t See above, p. 12i, note f. — H. 
 
 [26y, 263]
 
 CHAP. XIX 
 
 1 
 
 OF MATTER AND OF SPACE. 
 
 3-25 
 
 The reader may likewise be pleased to 
 attend to this, that, when I use the names of 
 tangible and visible space, I do not mean to 
 adopt Bishop Bei-keley's opinion, so far as 
 to think that they are really ditt'erent things, 
 and altogether unlike. I take them to be 
 different conceptions of the same thing ; 
 the one very partial, and the other more 
 complete ; but both distinct and just, as far 
 as they reach. [iG4] 
 
 Thus, when I see a spire at a very great 
 distance, it seems like the point of a bodkin ; 
 there appears no vane at the top, no angles. 
 But, when I view the same object at a small 
 distance, I see a huge pyramid of several 
 angles, with a vane on the top. Neither 
 of these appearances is fallacious. Each of 
 them is what it ought to be, and what it 
 must be, from such an object seen at such 
 different distances. These different appear- 
 ances of the same object may serve to illus- 
 trate the different conee[)tions of space, 
 according as they are drawn from the in- 
 formation of sight alone, or as they are 
 drawn from the additional information of 
 touch. 
 
 Our sight alone, unaided by touch, gives 
 a very partial notion of space, but yet a 
 distinct one. When it is considered accord- 
 ing to this partial notion, I call it visible 
 space. The sense of touch gives a nuieh 
 more complete notion of space ; and, when 
 it is considered according to this notion, I 
 call it tangible space. Perhaps there may 
 be intelligent beings of a higher order, whose 
 conceptions of space are nnich more com- 
 plete than those we have from both senses. 
 Another sense added to those of sight and 
 touch, might, for what I know, give us con- 
 ceptions of space as different from those we 
 can now attain as tangible sj)aee is from 
 visible, and might resolve many knotty 
 points concerning it, which, from the imper- 
 fection of our faculties, we cannot, by any 
 labour, untie. 
 
 Berkeley acknowledges that tliere is an 
 exact correspondence between the visible 
 figure and niagnitude of objects, and the 
 tangible ; and that every modification of 
 the one has a modification of the other cor- 
 responding, lie ackijowlc'dges, likewise, 
 that Nature has established such a con- 
 nection between the visible figure and mag- 
 nitude of an object, and the tangible, that 
 we learn by experience to know the tan- 
 gilile figure and magnitude from the visible. 
 And, having been accustomed to do so from 
 infancy, we get the habit of doing it with 
 such facility and quickness that we think 
 we see the tangiljle figure, magnitude, and 
 distance of bodies, when, in reality, we only 
 collect those tangible qualities from the 
 corresponding visible (|ualiticH, which are 
 natural signs of them. [2fj.'j] 
 
 The correspondence and connection which 
 l'2(i i-'2(ir,'] 
 
 Berkeley shews to be between the visible 
 
 figure and mngiiitude of objects, and their 
 tangible figure and magnitude, is in some 
 respects very similar to that which we have 
 observed between our sensations and the 
 primary qualities with which they are con- 
 nected. No sooner is the sensation felt, 
 than immediately we have the conception 
 and belief of the corresponding quality. 
 We give no attention to the sensation ; it 
 has not a name ; and it is difficult to per- 
 suade us that there was any such thing. 
 
 In like manner, no sooner is the visible 
 figure and magnitude of an object seen, than 
 immediately we have the conception and 
 belief of the corresponding tangible figure 
 and magnitude. We give no attention to 
 the visible figure and magnitude. It is 
 immediately forgot, as if it had never been 
 perceived ; and it has no name in common 
 language ; and, indeed, until Berkeley 
 pointed it out as a subject of speculation, 
 and gave it a name, it had none among 
 philosophers, excepting in one instance, 
 relating to the heavenly bodies, which are 
 beyond the reach of touch. With regard 
 to them, what Berkeley calls visible magni- 
 tude was, by astronomers, caHed apparent 
 magnitude. 
 
 There is surely an apparent magnitude, 
 and an apparent figure of terrestrial objects, 
 as well as of celestial ; and this is what 
 Berkeley calls their visible figure and mag- 
 nitude. But this was never made an object 
 of thought among philosophers, until that 
 author gave it a name, and observed the 
 correspondence and connection between it 
 and tangible magnitude and figure, and how 
 the mind gets the habit of passing so in- 
 stantaneously from the visible figure as a 
 sign to the tangible figure as the thing 
 signified by it, that the first is perfectly 
 forgot as if it had never been perceived. 
 
 [2m] 
 
 Visible figure, extension, and space, may 
 be made a subject of mathematical specula- 
 tion as well as the tangible. In the visible, 
 we find two dimensions only ; in the tan- 
 gible, three. In the one, magnitude is mea- 
 sured by angles ; in the otJier, by lines. 
 Every part of visible sjiace bears some pro- 
 portion to the whole ; but tangible space 
 being immense, any part of it bears no pro- 
 portion to the whole. 
 
 Such differences in their properties led 
 Bishop Berkeley to think that visible and 
 tangible magnitude and figure are things 
 totally different and dissimilar, and cannot 
 Ijoth belong to tiie same object. 
 
 And upon this dissimilitude is grounded 
 one of the strongest arguments l)y which his 
 sy.stein is supported. For il may be said, 
 if there be external objects which have a 
 real extension and figure, it must be either 
 tangible extension and (icun-, or visible, or
 
 326 
 
 ON THE INTELLECTUAL POWERS. 
 
 [^ESSAY II. 
 
 both.* The last appears absurd ; nor was 
 it ever maintained by any man, that the 
 same object lias two kinds of extension and 
 figure totally dissimilar. There is then only 
 one of the two really in the object ; and the 
 other must be ideal. But no i e.ison can be 
 assijjned why the perceptions of one sense 
 should be real, while those of another are 
 only ideal ; and he who is persuaded that 
 the objects of sijifht are ideas only, has 
 equal reason to believe so of the objects of 
 touch. 
 
 This argument, however, loses all its 
 force, if it be true, as was formerly hinted, 
 that visible figure and extension are only a 
 partial conception, and the tangible figure 
 and extension a more complete conception 
 of that f gure and extension which is really 
 iu the object-t [267] 
 
 It has been proved very fully by Bishop 
 Berkeley, that sight alone, without any aid 
 from the informations of touch, gives us no 
 perception, nor even conception of the dis- 
 tance of any object from the eye. But he 
 was not aware that this very principle over- 
 turns the argument for his system, taken 
 from the difference between visible and 
 tangible extension and figure. For, sup- 
 posing external objects to exist, and to have 
 that tangible extension and figure which we 
 perceive, it follows demonstrably, from the 
 principle now mentioned, that their visible 
 extension and figure must be just what we 
 see it to be. 
 
 The rules of perspective, and of the pro- 
 jection of the sphere, which is a branch of 
 perspective, are demonstrable. They sup- 
 pose the existence of external objects, which 
 have a tangible extension and figure ; and, 
 upon that supposition, they demonstrate 
 what must be the visibleextension and figure 
 of such objects, when placed in such a posi- 
 tion and at such a distance. 
 
 Hence, it is evident that tlie visible figure 
 and extension of objects is so far from being 
 incompatible with the tangible, that the first 
 is a necessary consequence from the last in 
 beings that see as we do. The correspond- 
 ence between them is not arbitrary, like that 
 between words and the thing they signify, as 
 Berkeley thought ; but it results necessarily 
 from the nature of the two senses ; and this 
 correspondence being always found in ex- 
 perience to be exactly what the rules ot per- 
 spective shew that it ought to be if the senses 
 give true information, is an argument of the 
 truth of both. 
 
 * Or neither. And this omilted supposition is the 
 true. For neither sight nor touch give us /»?; and 
 af('Hraf« information ui regard to the real extension 
 and figure of objects. See above p. liB, notes *; 
 and p. 303, col. li, note *.— H. 
 
 t if tangible figure and extension be only " a mwe 
 complete conception," &c., it cannot be a cognition 
 of real figure and extension. — H. 
 
 CHAPTER XX. 
 
 OF THE EVIDENCE OF SENSE, AND OF BELIEF 
 IN GENERAL. 
 
 The intention of nature in the powers 
 which we call the external senses, is evident. 
 They are intended to give us that informa- 
 tion of external objects which the Supreme 
 Being saw to be proper for us in our pre- 
 sent state ; and they give to all mankind 
 tlie information necessary for life, without 
 reasoning, without any art or investigation 
 on our part. [268] 
 
 The most uninstructed peasant has as 
 distinct a conception and as firm a belief 
 of the immediate objects of his senses, as 
 the greatest philosopher ; and with this he 
 rests satisfied, giving himself no concern 
 how he came by this conception and belief. 
 But the philosopher is impatient to know 
 how his conception of external objects, and 
 his belief of their existence, is produced. 
 This, I am afraid, is hid in impenetrable 
 darkness. But where there is no know- 
 ledge, there is the more room for conjecture, 
 and of this, philosophers have always been 
 very liberal. 
 
 The dark cave and shadows of Plato," the 
 species of Aristotle,-f- the films of Epicurus, 
 and the ideas and impressions of modern 
 philosophers,+ are the productions of human 
 fancy, successively invented to satisfy the 
 eager desire of knowing how we perceive 
 external objects ; but they are all deficient 
 in the two essential characters of a true and 
 philosophical account of the pbsenomenon : 
 for we neither have any evide.ice of their 
 existence, nor, if they did exist, can it be 
 shewn how they would produce perception. 
 
 It was before observed, that there are 
 two ingredients in this operation of percep- 
 tion : first, the conception or notion of the 
 object; and, seconrf/j/, the belief of its pre- 
 sent existence. Both are unaccountable. 
 
 That we can assign no adequate cause of 
 our first conceptions of things, I think, is 
 now acknowledged by the most enlightened 
 philosophers. We know that such is our 
 constitution, that in certain circumstances 
 we have certain conceptions ; but how they 
 are produced we know no more than how 
 we ourselves were produced. [269] 
 
 When we have got the conception of ex- 
 ternal objects by our senses, we can ana- 
 lyse them iu our thought into their sim- 
 ple ingredients ; and we can compound 
 those ingredients into various new forms, 
 which the senses never presented. But it is 
 
 * Pee p. 262, col. b, note *.— H. 
 
 \ See Note M— H. 
 
 ± Hy ideas, as repeatedly noticed, Reid under 
 stands always certain reprcrcntativc entities distinct 
 from the knowing mind. 
 
 [267-2091
 
 CHAP, XX.] 
 
 OF THE EVIDENCE OF SENSE, &c. 
 
 327 
 
 beyond the power of human imagination to 
 form any conception, whose simple ingre- 
 dients have not been furnislied by nature in a 
 manner unaccountable to our understanding. 
 
 We have an immediate conception of the 
 operations of our own minds, joined with a 
 a belief of their existence ; and this we call 
 consciousness.* But this is only giving a 
 name to this source of our knowledge. It 
 is not a discovery of its cause. In like man- 
 ner, we have, by our external senses, a 
 conception of external objects, joined with a 
 beUef of their existence ; and this we call 
 perception. But this is only giving a name 
 to another source of our knowledge, without 
 discovering its cause. 
 
 We know that, when certain impressions 
 are made upon our organs, nerves, and 
 brain, certain corresponding sensations are 
 felt, and certain objects are both conceived 
 and believed to exist. But in this train 
 of operations nature works in the dark. 
 We can neither discover the cause of any 
 one of them, nor any necessary connection 
 of one with another ; and, whether they 
 are connected by any necessary tie, or only 
 conjoined in our constitution by the will of 
 heaven, we know not.-j- 
 
 That any kind of impression upon a body 
 should be the efficient cause of sensation, ap- 
 pears very absurd. Nor can we perceive 
 any necessary connection between sensation 
 and the conception and belief of an external 
 object. For anything we can discover, we 
 might have been so framed as to have all 
 the sensations we now have by our senses, 
 without any impressions upon our organs, 
 and without any conception of any external 
 object. For anything we know, we miglit 
 have been so made as to perceive external 
 objects, without any impressions on bodily 
 organs, and without any of those sensa- 
 tions which invariably accompany percep- 
 tion in our present frame. [2/0] 
 
 If our conception of external objects be 
 unaccountable, the conviction and belief of 
 their existence, which we get by our senses, 
 is no less so.+ 
 
 * Here consciousness is made to consist in concep- 
 tion. I'ut, as Reid could hardly mean that con- 
 ecioiisness conceives (i. f., re|)re8t'nt6) the operations 
 about which it is conversant, and is not intuiiively 
 connisantot them, it woLild seem that he <)cca^i"nally 
 employs conception lor knowleilge. This is of im- 
 portance in ex|jlaiiiiiig favourably Keid's use of the 
 word Conception in relation to perception. Hut then, 
 how vanuc and vacillating is his language!— H. 
 
 t See p. Vo7, col. b, note *. — H. 
 
 X If an immediate kiiowlcdKe of external things — 
 that is, a consciousness of the qualities of the iion. 
 er/o — be admitted, the iciicf of their existence follows 
 of course. On this supposition, therelorc, such a 
 belief would not be unaccountable; for it would he 
 accounted for by the fact of the knowledge in which 
 It would necessarily he contained. Our belief, in this 
 case, of the existence of external (bjccis, would not 
 be mure inexplicable than our beliel that "<J + '.i = 1. 
 Ill both caei s it would be sutlicient to say, vc hclicrc 
 hrcautc iir knniv; for I.elicf i> only una'counlabic 
 when it i< not the consequent or concomitant of 
 I -^70 o; 1 -| 
 
 Belief, assent, conviction, are words 
 which I do I. ot think admit of logical defin- 
 ition, because the operation of mind sig- 
 nified by them is perfectly simple, and of 
 its own kind. Nor do they need to be de- 
 fined, because they are common words, and 
 well understood. 
 
 Belief must have an object. For he 
 that believes must believe something ; and 
 that which he believes, is called the object 
 of his belief. Of this object of his belief, 
 he must have some conception, clear or ob- 
 scure ; for, although there may be the most 
 clear and distinct conception of an object 
 without any belief of its existence, there 
 can be no belief without conception. * 
 
 Belief is always expressed in language by 
 a proposition, wherein something is affirmed 
 or denied. This is the form of speech 
 which in all languages is appropriated to 
 that purpose, and without belief there could 
 be neither affirmation nor denial, nor should 
 we have any form of words to express 
 either. Belief admits of all degrees, from 
 the slightest suspicion to the fullest assur- 
 ance. These things are so evident to 
 every man that reflects, that it would be 
 abusing the reader's patience to dwell upon 
 them. 
 
 I proceed to observe that there are many 
 operations of mind m which, when we 
 analyse them as far as we are able, we find 
 belief to be an essential ingredient. A man 
 cannot be conscious of his own thoughts, 
 without believing that he thinks. He can- 
 not perceive an object of sense, without be- 
 lieving that it exists. -j- He cannot distinctly 
 remember a past event, without believing 
 that it did exist. Belief therefore is an 
 ingredient in consciousness, in perception, 
 and in remembrance. L271] 
 
 Not only in most of our intellectual oper- 
 ations, but in many of the active princi- 
 ples of the human mind, belief enters as an 
 ingredient. Joy and sorrow, hope and 
 fear, imply a belief of good or ill, either pre- 
 sent or in expectation- Esteem, gratitude, 
 pity, and resentment, imply a belief of cer- 
 tain qualities in their objects. In every 
 action that is done for an end, there must 
 be a belief of its tendency to that end. So 
 large a share has belief in our intellectual 
 
 knowledge. By this, however, I do not, of course, 
 mean to say that knowledge is not in itself marvel- 
 lous and unaccountable. I'his statement ol Keid 
 agiiin favours the opinion that his doctrine of percep- 
 tion is not really inimediale. — H. 
 
 * Is aincnitioH here equivalent to knowlolijc or to 
 Oiowiiif.'—IL 
 
 t Mr .Stewart {Elem. 1., ch. iii., p. 116, and Essat/s, 
 11., ch. ii., p. "S). .«y.) proposes a supplement to this 
 doctrine of Held, in order to explain why we believe 
 in the existence ot the qualities of external objects 
 when thev are not the olijicts of our perception. 
 'Ibis beliei he holds to be the result of c.i/n c/c/iiv, in 
 combination with an original |iiiiiciple ol (lur consti. 
 tuiioii, wlnTcliv we arc ilrtiriniind In hulitve in Uic 
 pcrmannicr tif llif Inirs <if luilun.— W
 
 328 
 
 ON THE INTELLECTUAL POV/EIIS. 
 
 [essav Ii. 
 
 operations, in our active principles, and in 
 our actions themselves, that, as faith in 
 things divine is represented as the main 
 spring in the life of a Christian, so belief in 
 general is the main spring in the life of a man. 
 
 That men often believe what there is no 
 just ground to believe, and thereby are led 
 into hurtful errors, is too evident to be 
 denied. And, on the other hand, that there 
 are just grounds of belief can as little be 
 doubted by any man who is not a perfect 
 sceptic. 
 
 We give the name of evidence to what- 
 ever is a ground of belief. To believe with- 
 out evidence is a weakness which every 
 man is concerned to avoid, and which every 
 man wishes to avoid. Nor is it in a man's 
 power to believe anytliing longer than he 
 thinks he has evidence. 
 
 What this evidence is, is more easily felt 
 than described. Those who never reflected 
 upon its nature, feel its influence in govern- 
 ing their belief. It is the business of the 
 logician to explain its nature, and to dis- 
 tinguish its various kinds and degrees ; but 
 every man of understanding can judge of it, 
 and commonly judges right, when the evi- 
 dence is fairly laid before him, and his 
 mind is free from prejudice. A man who 
 knows nothing of the theory of vision may 
 have a good eye; and a man who never 
 speculated about evidence in the abstract 
 may have a good judgment. [272] 
 
 The common occasions of life lead us to 
 distinguish evidence into different kinds, to 
 which we give names that are well under- 
 stood ; such as the evidence of sense, the 
 evidence of memory, the evidence of con- 
 sciousness, the evidence of testimony, the 
 evidence of axioms, the evidence of reason- 
 ing. All men of common understanding: 
 agree that each of these kinds of evidence 
 may afford just ground of belief, and they 
 agree very generally in tlie circumstances 
 that strengthen or weaken them. 
 
 Philosophers have endeavoured, by ana- 
 lysing the different sorts of evidence, to 
 iind out some common natui-e wherein they 
 all agree, and thereby to reduce them all 
 to one. This was the aim of tlie school- 
 naen in their intricate disputes about the 
 criterion of truth. Des Cartes placed this 
 criterion of truth in clear and distinct per- 
 ception, and laid it down as a maxim, that 
 whatever we clearly and distinctly perceive 
 to be true, is true ; but it is difficult to 
 know what he understands by clear and 
 distinct perception in this maxim. Mr 
 Locke placed it in a perception of the agree- 
 ment or disagreement of our ideas, which 
 perception is immediate in intuitive know- 
 ledge, and by thi- intervention of other ideas 
 in reasoning. 
 
 I confess that, although I have, as I 
 t'unk. a distinct notion of the different 
 
 kinds of evidence above-mentioned, and, 
 perhaps, of some others, which it is unne- 
 cessary here to enumerate, yet I am not 
 able to find any common nature to which 
 they may al! be reduced. They seem to 
 me to agree only in this, that they are all 
 fitted by Nature to produce belief in tlie 
 human mind, some of them in tlie h ghest 
 degree, wliich we call certainty, others in 
 various degrees according to circumstances. 
 
 I shall take it for granted tliat the evi- 
 dence of sense, when the proper circum- 
 stances concur, is good evidence, and a just 
 ground of belief. JNIy intention in this 
 jilace is only to compare it with the other 
 kinds that have been mentioned, that we 
 may judge whether it be reducible to any of 
 them, or of a nature peculiar to itself. [273] 
 
 First, It seems to be quite different from 
 the evidence of reasoning. All good evi- 
 dence is commonly called reasonable evi- 
 dence, and very justly, because it ought to 
 govern our belief as reasonable creatures. 
 And, according to this meaning, I think the 
 evidence of sense no less reasonable than 
 that of demonstration.* If Nature give 
 us information of things that concern us, 
 by other means than by reasoning, reason 
 itself will direct us to receive that inform- 
 ation with thankfulness, and to make the 
 best use of it. 
 
 But, when we speak of the evidence of 
 reasoning as a particular kind of evidence, 
 it means the evidence of propositions that 
 are inferred by reasoning, from propositions 
 already known and believed. Thus, the 
 evidence of the fifth proposition of the 
 first book of Euclid's Elements consists in 
 this. That it is shewn to be the necessary 
 consequence of the axioms, and of the pre- 
 ceding propositions. In all reasoning, there 
 must be one or more premises, and a con- 
 clusion drawn from them. And the pre- 
 mises are called the reason why we must 
 believe the conclusion which we see to fol- 
 low from them. 
 
 That the evidence of sense is of a differ- 
 ent kind, needs little proof. No man seeks 
 a reason for believing what he sees or feels ; 
 and, if he did, it would be difficult to find 
 one. But, thougli he can give no reason 
 for believing his senses, his belief remains 
 as firm as if it were grounded on demon- 
 stration. 
 
 Many eminent philosophers, thinking it 
 unreasonable to believe when they could not 
 shew a reason, have laboured to furnish us 
 with reasons for believins our senses ; but 
 their reasons are very insufficient, and 
 will not bear examination, Otlier philoso- 
 
 ZiGtvoicc;. — A?' loth'. TloQ(rix,iiv ov hu Tavroe. roi? hioe, 
 
 ffl. 'I'v; ccier8Y,/rii ^ccAAov *3 tm }^oyoo Tt^ii/riov' Tice.) roi; 
 Xoyotg. Vccv QfAoXoyo'JfAivcc iuxvCojin Tot?* (^ixivouivois-^ 
 
 L272, 273J
 
 CHAP. KX 
 
 •] 
 
 OF THE EVIDENCE OF SENSE, &c. 
 
 329 
 
 pliers have shewn very clearly the fallacy 
 of these reasons, and have, as they imagine, 
 discovered invincible reasons against this be- 
 lief ; but they have never been able either 
 to shake it in themselves, or to convince 
 others. [274] The statesman continues to 
 plod, the soldier to fight, and the merchant 
 to export and import, without being in the 
 least moved by the demonstrations that 
 have been offered of the non-existence of 
 those things about which they are so seri- 
 ously employed. And a man may as soon, 
 by reasoning, pull the moon out of her orbit, 
 as destroy the belief of the objects of sense. 
 
 Shall we say, then, that the evidence 
 of sense is the same with that of axioms, 
 or self-evident truths ? I answer, First, 
 That, all modern philosophers seem to agree 
 that the existence of the objects of sense 
 is not self-evident, because some of them 
 have endeavoured to prove it by subtle rea- 
 soning, others to refute it. Neither of 
 these can consider it as self-evident. 
 
 Seeondly, I would observe that the word 
 axiom is taken by philosophers in such a 
 sense as that the existence of the objects 
 of sense cannot, with propriety, be called 
 an axiom. They give the name of axiom 
 only to self-evident truths, that are neces- 
 sary, and are not limited to time and place, 
 but must be true at all times and in all 
 places. The truths attested by our senses 
 are not of this kind ; they are contingent, 
 and limited to time and place. 
 
 Thus, that one is the half of two, is an 
 axiom. It is equally true at all times and 
 in all places. We perceive, by attending 
 to the proposition itself, that it cannot but 
 be true ; and, therefore, it is called an eter- 
 nal, necessary, and immutable truth. Tliat 
 there is at present a chair on my right hand, 
 and another on my left, is a truth attested 
 by my senses ; but it is not necessary, nor 
 eternal, nor immutable. It may not be 
 true next minute ; and, therefore, to call it 
 an axiom would, I api)rehend, be to deviate 
 from the connnon use of the word. 1-75] 
 
 Thirdly, If the word axiom be \>\xt to 
 signify every truth which is known innne- 
 diately, without being deduced from any 
 antecedent truth, then the existence of the 
 objects of sense may be called an axiom ; 
 for my senses give me :is immediate con- 
 viction of what they testify, as my under- 
 standing gives of what is commonly called 
 an axiom. 
 
 There is, no doubt, an analogy between 
 tlie evidence of sense and the evidence of 
 testimony. lieneo, we find, in all lan- 
 guages, the analogical expressions of the 
 tenUmoin/ of sense, of giving rn'ilil to our 
 senses, and the like. ]5ut there is a real 
 difference between the two, as well as a 
 similitude. In lielii.ving ui)on testimony, 
 we rely upon tbf aiilli'irity of a iw'rson who 
 
 testifies ; but we have no such authority for 
 believing our senses. 
 
 Shall we say, then, that this belief is the 
 inspiration of the Almighty ? I think this 
 may be said in a good sense ; for I take it 
 to be the immediate effect of our constitu- 
 tion, which is the work of the Almighty. 
 But, if inspiration be understood to imply 
 a persuasion of its coming from God, our 
 belief of the objects of sense is not inspira- 
 tion ; for a man would believe his senses 
 though he had no notion of a Deity. He 
 who is persuaded that he is the workman- 
 ship of God, and that it is a part of his 
 constitution to believe his senses, may 
 think that a good reason to confirm his 
 belief. But he had the belief before he could 
 give this or any other reason for it. 
 
 If we compare the evidence of sense with 
 that of memory, we find a great resem- 
 blance, but still some difference. I remem- 
 ber distinctly to have dined yesterday with 
 such a company. What is the meaning of 
 this ? It is, that I have a distinct con- 
 ception and firm belief of this past event ; 
 not by reasoning, not by testimony, but 
 immediately from my constitution. And I 
 give the name of memory to that part of 
 my constitution by which I have this kind 
 of conviction of past events. [276] 
 
 I see a chair on my right hand. What 
 is the meaning of this ? It is, that I have, 
 by my constitution, a distinct conception 
 and firm belief of the present existence of 
 the chair in such a place and in such a 
 position ; and I give the name of seeing to 
 that part of my constitution by which I 
 have this immediate conviction. The two 
 operations agree in the immediate convic- 
 tion which they give. They agree in this 
 also, that the things believed are not 
 necessary, but contingent, and limited to 
 time and place. But they differ in two 
 respects : —First, That memory has some- 
 thing for its object that did exist in time 
 past ; but the object of sight, and of all the 
 senses, must be something which exists at 
 present ; — and, Seconil/i/, That I see by my 
 eyes, and only when they are directed to 
 the object, and when it is illuminated. But 
 my memory is not limited by any bodily 
 organ that I know, nor by light and dark- 
 ness, though it has its limitations of another 
 kind.* 
 
 These diflerences are obvious to all men, 
 and very reasonably lead them to consider 
 seeing and remembering as operations spe- 
 cifically diflerent. But the nature of the 
 evidence they give, has a great resemblance. 
 
 * There is a more important difference Jliaii these 
 oinittiil. Ill memory, we cannot pii >il)ly lie con- 
 si iiius or iiiinuili lely connis.mf of any oliji ct luyonil 
 the niodKii-atioiis oC ilic ,vi' ilsclC. In |ier<eptioii, (if 
 an iiiiiiicdiiit,- iii'i-crjiliiin he aMowed,) >ie nuist lie 
 conscious, or innncdiately ciiyniitanl, ol sc me pha'no- 
 nieiion of the Hvii-iyo. — H.
 
 330 
 
 ON THE INTELLECTUAL POWERS. 
 
 [[essay n. 
 
 A like difference and a like resemblance 
 there is between the evidence of sense and 
 that of consciousness, which I leave the 
 reader to trace. 
 
 As to the opinion that evidence consists 
 in a perception of the agreement or dis- 
 agreement of ideas, we may have occasion 
 to consider it more particularly in another 
 place. Here I only observe, that, when 
 taken in the most favourable sense, it may 
 be applied with propriety to the evidence of 
 reasoning, and to the evidence of some 
 axioms. But I cannot see how, in any 
 sense, it can be applied to the evidence of 
 consciousness, to the evidence of memory, 
 or to that of the senses. 
 
 When I compare the different kinds of 
 evidence above-mentioned, I confess, after 
 all, that the evidence of reasoning, and that 
 of some necessary and self-evident truths, 
 seems to be the least mysterious and the 
 most perfectly comprehended ; and there- 
 fore I do not think it strange that philoso- 
 phers should have endeavoured to reduce all 
 kinds of evidence to these. [277] 
 
 When I see a proposition to be self-evi- 
 dent and necessary, and that the subject is 
 plainly included in the predicate, there seems 
 to be nothing more that I can desire in order 
 to understand why I believe it. And when 
 I see a consequence that necessarily follows 
 from one or more self-evident propositions, I 
 want nothing more with regard to my belief 
 of that consequence. The light of truth so 
 fills my mind in these cases, that I can 
 neither conceive nor desire anything more 
 satisfying. 
 
 On the other hand, when I remember dis- 
 tinctly a past event, or see an object before 
 my eyes, this commands my belief no less 
 than an axiom. But when, as a philosopher, 
 I reflect upon this belief, and want to trace it 
 to its origin, I am not able to resolve it into 
 necessary and self-evident axioms, or con- 
 clusions that are necessarily consequent 
 upon them. I seem to want that evidence 
 which I can best comprehend, and which 
 gives perfect satisfaction to an inquisitive 
 mind ; yet it is ridiculous to doubt ; and I 
 find it is not in my power. An attempt to 
 throw off this belief is like an attempt to fly, 
 equally ridiculous and impracticable. 
 
 To a philosopher, who has been accus- 
 tomed to think that the treasure of his know- 
 ledge is the acquisition of that reasoning 
 power of which he boasts, it is no doubt 
 humiliating to find that his reason can lay no 
 claim to the greater part of it. 
 
 By his reason, he can discover certain 
 abstract and necessary relations of things ; 
 but his knowledge of what really exists, or 
 did exist, comes by another channel, which 
 is open to those who cannot reason. He is 
 led to it in the dark, and knows not how he 
 came by it. [278] 
 
 It is no wonder that the pride of philo- 
 sophy should lead some to invent vain 
 theories in order to account for this know- 
 ledge ; and others, who see this to be im- 
 practicable, to spurn at a knowledge they 
 cannot account for, and vainly attempt to 
 throw it off as a reproach to their under- 
 standing. But the wise and the humble 
 will receive it as the gift of Heaven, and 
 endeavour to make the best use of it. 
 
 CHAPTER XXI. 
 
 OF THE IMPROVEMENT OF THE SENSES. 
 
 Our senses may be considered in two 
 views : first, As they afford us agreeaVjle 
 sensations, or subject us to such as are dis- 
 agreeable; and, secondly. As they give us 
 information of things that concern us. 
 
 In i\\Q first view, they neither require nor 
 admit of improvement. Both the painful 
 and the agreeable sensations of our external 
 senses are given by nature for certain ends ; 
 and they are given in that degree which is 
 the most proper for their end. By dimin- 
 ishing or increasing them, we should not 
 mend, but mar the work of Nature. 
 
 Bodily pams are indications of some dis- 
 order or hurt of the body, and admonitions 
 to use the best means in our power to pre- 
 vent or remove their causes. As far as this 
 can be done by temperance, exercise, regi- 
 men, or the skill of the physician, every man 
 hath sufficient inducement to do it. 
 
 When pain cannot be prevented or re- 
 moved, it is greatly alleviated by patience 
 and fortitude of mind. While the mind is 
 superior to pain, the man is not unhappy, 
 though he may be exercised. It leaves no 
 sting behind it, but rather matter of triumph 
 and agreeable reflection, when borne pro- 
 perly, and in a good cause. [279] The 
 Canadians have taught us that even savages 
 may acquire a superiority to the most ex- 
 cruciating pains ; and, in every region of 
 the earth, instances will be found, where a 
 sense of duty, of honour, or even of worldly 
 interest, have triumphed over it. 
 
 It is evident that nature intended for man, 
 in his present state, a life of labour and 
 toil, wherein he may be occasionally exposed 
 to pain and danger ; and the happiest man 
 is not he who has felt least of those evils, 
 but he whose mind is fitted to bear them by 
 real magnanimity. 
 
 Our active and perceptive powers are 
 improved and perfected by use and exercise. 
 This is the constitution of nature. But, 
 with regard to the agreeable and disagree- 
 able sensations we have by our senses, the 
 very contrary is an established constitution 
 of nature — the frequent repetition of them 
 weakens their force. Sensations at first very 
 
 [277-279"l
 
 CHAP. XXI.] OF THE IMPROVEMENT OF THE SENSES. 
 
 331 
 
 disagreeable, by use become tolerable, and 
 at last perfectly indifferent. And those that 
 are at first very agreeable, by frequent re- 
 petition become insipid, and at last, per- 
 haps, give disgust. Nature has set limits 
 to the pleasures of sense, which we cannot 
 pass ; and all studied gratifications of them, 
 as it is mean and unworthy of a man, so it 
 is foohsh and fruitless. 
 
 The man who, in eating and drinking, 
 and in other gratifications of sense, obeys 
 the calls of Nature, without affecting deli- 
 cacies and refinements, has all the enjoy- 
 ment that the senses can afford. If one 
 could, by a soft and luxurious life, acquire 
 a more delicate sensibility to pleasure, it 
 must be at the expense of a Uke sensibility 
 to pain, from which he can never promise 
 exemption, and at the expense of cherishing 
 many diseases which produce pain. 
 
 The improvement of our external senses, 
 as they are the means of giving us informa- 
 tion, is a subject more worthy of our atten- 
 tion ; for, although they are not the noblest 
 and most exalted powers of our nature, yet 
 they are not the least useful. [280] All 
 that we know, or can know, of the material 
 world, must be grounded upon their inform- 
 ation ; and the philosopher, as well as the 
 day-labourer, must be indebted to them for 
 the largest part of his knowledge. 
 
 Some of our perceptions by the senses 
 may be called original, because they require 
 no previous experience or learning ; but 
 the far greatest part is acquired, and the 
 fruit of experience. 
 
 Three of our senses — to wit, smell, taste, 
 and hearing — originally give us only certain 
 sensations, and a tonviction that these sensa- 
 tions are occasioned by some external object. 
 We give a name to that quality of the ob- 
 ject by which it is fitted to produce such a 
 sensation, and connect that quality with the 
 object, and with its other qualities. 
 
 Thus we learn, that a certain sensation 
 of smell is produced by a rose ; and that 
 quality in the rose, by which it is fitted to 
 produce this sensation, we call the smell of 
 the rose. Here it is evident that the sensa- 
 tion is original. The perception that the 
 rose has that quality which we call its 
 smell, is acquired. In like manner, we 
 learn ail tliose (jualities in b(jdies which we 
 call their smell, their taste, their sound. 
 These are all secondary qualities, and we 
 give the same name to them which we give 
 to the sensations they produce; not from 
 any similitude l)etween the sensation and 
 the quality of the same name, but because 
 the quality is signified to us by the sensation 
 as its sign, and jjecause our senses give us 
 no other knowledge of the quality but that 
 it is fit to produce such a sensation. 
 
 By the other two senses, we have much 
 more ample information. By sight, we 
 
 learn to distinguish objects by their colour, 
 in the same manner as by their sound, 
 taste, and smell. By this sense, we perceive 
 visible objects to have extension in two 
 dimensions, to have visible figure and 
 magnitude, and a certain angular distance 
 from one another. These, 1 conceive, are 
 the original perceptions of sight.* [281] 
 
 By touch, we not only perceive the tem- 
 perature of bodies as to heat and cold,-|- 
 which are secondary qualities, but we per- 
 ceive originally their three dimensions, tlieir 
 tangible figure and magnitude, their linear 
 distance from one another, their hardness, 
 softness, or fluidity. These qualities we 
 originally perceive by touch only ; but, by 
 experience, we learn to perceive all or most 
 of them by sight. 
 
 We learn to perceive, by one sense, what 
 originally could have been perceived only 
 by another, by finding a connection between 
 the objects of the ditt'erent senses. Hence 
 the original perceptions, or the sensations 
 of one sense become signs of whatever has 
 always been found connected with them ; 
 and from the sign, the mind passes imme- 
 diately to the conception and belief of the 
 thing signified. And, although the connec- 
 tion in the mind between the sign and the 
 thing signified by it, be the effect of custom, 
 this custom becomes a second nature, and 
 it is difficult to distinguish it from the ori- 
 ginal power of perception. 
 
 Thus, if a sphere of one uniform colour 
 be set before me, I perceive evidently by my 
 eye its spherical figure and its three dimen- 
 sions. All the world will acknowledge 
 that, by sight only, without touching it, I 
 may be certain that it is a sphere ; j'et it 
 is no less certain that, by the original power 
 of sigiit, I could not perceive it to be a 
 sphere, and to have three dimensions. The 
 eye originally could only perceive two di- 
 mensions, and a gradual variation of colour 
 on the ditt'erent sides of the object. 
 
 It is experience that teaches me that the 
 variation of colour is an ett'ect of spherical 
 convexity, and of the distribution of Iglit 
 and shade. But so rapid is the progress of 
 the thought, from the effect to the cause, 
 that we attend only to the last, and can 
 harilly be persuaded that we do not imme- 
 diately see the three dimensions of the 
 sphere. [282] 
 
 Nay, it may be observed, that, in this 
 case, the acquired perception in a ra;inner 
 effaces the original one; for the sjilicre is 
 seen to be of one uniform colour, tlio\igh 
 originally there woukl have ajipeaied a 
 gradual variation of colour. But that .^p- 
 
 * See above, p. 123, col. li, note (, and p. 1S5, col. i, 
 note *. 
 
 1 Whcthf-r lie.if, coliI, &o., be (ibjncls of touch 
 of a (lilHreiit wiixe, it i> nol here the I'liii'o loimiuli 
 - II.
 
 332 
 
 ON THE INTELLECTUAL POWERS. 
 
 [essay h. 
 
 parent variation we learn to interpret as 
 the effect of light and shade falling upon a 
 sphere of one uniform colour, 
 
 A spliere may be painted upon a plane, 
 so exactly, as to be tiiken for a real sphere 
 when the eye is at a proper distance find 
 in the proper point of view. We say in 
 this case, that the eye is deceived, that the 
 appearance is fallacious. But there is no 
 fallacy in the original perception, but only 
 in that which is acquired by custom. The 
 variation of colour, exhibited to the ej'e by 
 the painter's art, is the same which nature 
 exhibits by the different degrees of light 
 falling u]>on the convex surface of a sphere. 
 
 In perception, whether original or ac- 
 quired, there is something which may be 
 called tlie sign, and something which is 
 signified to us, or brought to our knowledge 
 by that sign. 
 
 In original perception, the signs ai'e the 
 various sensations which are produced by 
 the impressions made upon our organs. The 
 things signified, are the objects perceived 
 in consequence of those sensations, by the 
 original constitution of our nature. 
 
 Thus, when I grasp an ivory ball in my 
 hand, I have a certain sensation of touch. 
 Although this sensation be in the mind and 
 have no similitude to anything material, 
 yet, by the laws of my constitution, it is 
 immediately followed by the conception 
 and belief, that there is in my hand a hard 
 smooth body of a spherical figure, and about 
 an inch and a half in diameter. This belief 
 is grounded neither upon reasoning, nor 
 upon experience ; it is the immediate effect 
 of my constitution, and this I call original 
 perception.* [283] 
 
 In acquired perception, the sign may be 
 either a sensation, or something originally 
 perceived. The thing signified, is something 
 which, by experience, has been found con- 
 nected with that sign. 
 
 Thus, when the ivory ball is placed be- 
 fore my eye, I perceive by sight what I 
 before perceived by touch, that the ball is 
 smooth, spherical, of such a diameter, and 
 at such a distance from the eye ; and to 
 this is added the percej)tion of its colour. 
 All these things I perceive by sight, dis- 
 tinctly and with certainty. Yet it is cer- 
 tain from principles of pliilosophy, that, if I 
 had not been accustomed to compare the 
 informations of sight with those of touch, 
 I should not have perceived tliese things 
 by sight. I should have perceived a circu- 
 lar object, having its colour gradually more 
 faint towards the shaded side. But I should 
 not have perceived it to have three dimen- 
 sions, to be spherical, to be of such a linear 
 magnitude, and at such a distance from the 
 eye. That these last mentioned are not 
 
 * Seeabovp, y. Ill, n^Ubi.— H. 
 
 original perceptions of sight, but acquired 
 by experience, is suflSciently evident from 
 the principles of optics, and from the art of 
 painters, in painting objects of three dimen- 
 sions, upon a plane which has only two. 
 And it has been put beyond all doubt, by 
 observations recorded of several persons, 
 who having, by cataracts in their eyes, 
 been deprived of sight from their infancy, 
 have been couched and made to see, after 
 they came to years of understanding," 
 
 Those who have had their eyesight from 
 infancy, acquire such perceptions so early 
 that they cannot recollect the time when 
 they had them not, and therefore make no 
 distinction between them and their original 
 perceptions ; nor can they be easily per- 
 suaded that there is any just foundation 
 for such a distinction, [284] In all lan- 
 guages men speak with equal assurance of 
 their seeing objects to be spherical or cubi- 
 cal, as of their feeling them to be so ; nor 
 do they ever dream that these perceptions 
 of sight were not as early and original as 
 the perceptions they have of the same ob- 
 jects by touch. 
 
 This power which we acquire of perceiv- 
 ing things by our senses, which originally 
 we should not have perceived, is not the 
 effect of any reasoning on our part : it is 
 the result of our constitution, and of the 
 situations in which we happen to be placed. 
 
 "We are so made that, when two things 
 are found to be conjoined in certain circum- 
 stances, we are prone to believe that they 
 are connected by nature, and will always be 
 found together in like circumstances. The 
 belief which we are led into in such cases is 
 not the effect of reasoning, nor does it arise 
 from intuitive evidence in the thing believed ; 
 it is, as I apprehend, the innnediate effect of 
 our constitution. Accordingly, it is strongest 
 in infancy, before our reasoning power 
 appears — before we are capable of draw- 
 ing a conclusion from premises, A child 
 who has once burnt his finger in a candle, 
 from that single instance connects the pain 
 of burning with putting his finger in the 
 candle, and believes that these two things 
 must go together. It is obvious that this 
 part of our constitution is of very great use 
 before we come to the use of re:ison, and 
 guards'us from a thousand mischiefs, which, 
 without it, we would rusli into ; it may 
 sometimes lead us into error, but the good 
 effects of it far overbalance the ill. 
 
 It is, no doubt, the perfection of a rational 
 being to have no belief but what is grounded 
 on intuitive evidence, or on just reasoning : 
 but man, I apprehend, is not such a being ; 
 nor is it the intention of nature that he 
 should be such a being, m every period of 
 his existence. We come into the world 
 
 * See above, p. 136, note t, and p. 182, note *. — H. 
 
 [283, 28 t]
 
 CHAP. XXI.] OF THE IMPROVEMENT OF THE SENSES. 
 
 333 
 
 without the exercise of reason ; we are 
 merely animal before we are rational crea- 
 tures ; and it is neeessary for our preserva- 
 tion, that we should believe many tilings be- 
 fore we can reason. How then is our belief 
 to be regulated before we have reason to 
 regulate it ? [-85] Has nature left it to be 
 regulated by chance ? By no means. It is 
 regulated by certain principles, which are 
 parts of our constitution ; whether they 
 ought to be called animal principles, or m- 
 stinctive principles, or what name we give 
 to them, is of small moment ; but they are 
 certainly different from the faculty of rea- 
 son : they do the office of reason while it is 
 in its infancy, and must, as it M'ere, be car- 
 ried in a nurse's arms, and thev are leadiun;- 
 strings to it in its gradual progress. 
 
 From what has been sai<l, I think it ap- 
 pears that our original powers of perceiving 
 objects by our senses receive great improve- 
 ment by i.se and habit ; and without this 
 improvement, would be altogether insuf- 
 ficient for the purposes of life. The daily 
 occurrences of life not only add to our stock 
 of knowledge, but give additional percep- 
 tive powers to our senses ; and time gives 
 us the use of our eyes and ea;s, as \vell as 
 of our hands and legs. 
 
 This is the greatest and most important 
 improvement of our external senses. It is 
 to be found in all men come to years of un- 
 derstanding, but it is various in difi'erent 
 persons according to their different occupa- 
 tions, and the different circumstances in 
 whicli they are placed. Every aitist re- 
 quires an eye as well as a hand in his own 
 profession ; his eye becomes skilled m per- 
 ceiving, no less than his hand in executing, 
 what belongs to his employment. 
 
 Besides this improvement of our senses, 
 which nature produces without our inten- 
 tion, there are various ways in v,liic!i they 
 may be improved, or their defects re- 
 medied by art. As, first, by a due care of 
 the organs of sense, that they be in a sound 
 and natural state. This belongs to the de- 
 partment of the medical faculty. 
 
 Secnndli/, By accurate attention to the 
 objects of sense. The effects of such atten- 
 tion in improving our senses, appear in every 
 art. The aitist, by giving more attention 
 to certain objects than others do, by that 
 means perceives many things in those ob- 
 jects which others do not- [280] Those 
 who happen to be deprived of one sense, 
 frequently supjily that defect in a great de- 
 gree, by giving more accurate attention to 
 llie objects of the senses they liave. The 
 blind l];ive often been known to acquii-e uii- 
 comrniin acuteness in distinguishing things 
 by feeling and hearing ; and the deaf are 
 uncommonly quick in reading men's thoughts 
 in their c(juntenance 
 
 A third way in which our senses admit of 
 
 improvement, is, by additional organs, or in- 
 struments contrived by art. By the inven- 
 tion of optical glasses, and the gradual im- 
 provement of them, the natural power of 
 vision is wonderfully improved, and a vast 
 addition made to the stock of knowledge 
 which we acquire by the eye. By speaking- 
 trumpets and ear-trunipcts some improve- 
 ment has been made in the sense of hearing. 
 Whether by similar inventions the other 
 senses may be improved, seems uncertain. 
 
 A fourth method by which the informa- 
 tion got by our senses may be improved, is, 
 by discovering the connection which nature 
 hath established between the sensible quali- 
 ties of objects, and their more latent qualities. 
 
 By the sensible qualities of bodies, I un- 
 derstand those that are perceived immedi- 
 ately by the senses, such as their colour, 
 figure, feeling, sound, taste, smell. The 
 various modifications and various combin- 
 ations of these, are innumerable ; so that 
 there are hardly two individual bodies in 
 Nature that may not be distinguished by 
 their sensible qualities. 
 
 The latent qualities are such as are not 
 immediately discovered by our senses ; but 
 discovered sometimes by accident, some- 
 times by experiment or observation. The 
 most important part of our knowledge of 
 bodies is the knowledge of the latent qua- 
 lities of the several species, by which they 
 are adapted to certain purposes, either for 
 food, or medicine, or agriculture, or for the 
 materials or utensils of some art or manu- 
 fiicture. [287] 
 
 I am taught that certain species of bodies 
 have certain latent qualities; but how shall 
 I know that this individual is of such a 
 species ? This must be known by the sen- 
 sible qualities which characterise the species. 
 I must know that this is bread, and that 
 wine,- before I eat the one or drink the 
 other. 1 must know that this is rhubarb, 
 and that opium, before I use the one or the 
 other for medicine. 
 
 It is one branch of human knowledge to 
 know the names of the various sj)ecies of 
 natural and artificial bodies, and to know 
 the iiensible qualities by which they are 
 ascertained to be of such a species, and by 
 which they are distingui^^lu'd ironi one an- 
 other. It is another branch of knowledge 
 to know the latent qualities of the several 
 species, and the uses to which they are 
 subservient. 
 
 The nian who possesses both these 
 branches is inforuiod, by his sei ses, (if in- 
 numerable tilings of real moincnt which are 
 hid from those who possess only one, or 
 neither. This is an hnprovement in tlio 
 mformation got by our senses, which must 
 keep jiace with the improvements made in 
 natural history, in natural philosophy, aud 
 '11 the arts.
 
 334 
 
 ON THE INTELLECTUAL POWERS. 
 
 j_ESSAY n. 
 
 It would be an improvement still higher 
 if we were able to discover any connection 
 between the sensible qualities of bodies and 
 their latent qualities, without knowing the 
 species, or what may have been discovered 
 with regard to it. 
 
 Some philosophers, of the first rate, have 
 made attempts towards this noble improve- 
 ment, not without promising hopes of suc- 
 cess. Thus, the celebrated Linnteus has 
 attempted to point out certain sensible qua- 
 lities by which a plant may very probably 
 be concluded to be poisonous witiiout know- 
 ing its name or species. He has given se- 
 veral other instances, wherein certain medi- 
 cal and economical virtues of plants are 
 indicated by their external appearances. 
 Sir Isaac Newton hath attempted to shew 
 that, from the colours of bodies, we may 
 form a probable conjecture of the size of 
 their constituent parts, by which the rays 
 of light are reflected. [288] 
 
 No man can pretend to set limits to the 
 discoveries that may be made by human 
 genius and industry, of such connections 
 between the latent and the sensible quali- 
 ties of bodies. A wide field here opens to 
 our view, whose boundaries no man can 
 ascertain, of improvements that may here- 
 after be made in the information conveyed 
 to us by our senses. 
 
 CHAPTER XXIL 
 
 OF THE FALLACY OF THE SENSES. 
 
 Complaints of the fallacy of the senses 
 have been very common in ancient and in 
 modern times, especially among the philo- 
 sophers. And, if we should take for granted 
 all that they have said on this subject, the 
 naturai conclusion from it might seem to 
 be, that the senses are given to us by some 
 malignant demon on purpose to delude us, 
 rather than that they are formed by the 
 wise and beneficent Author of Nature, to 
 give us true information of things necessary 
 to our preservation and happiness. 
 
 The whole sect of atomists among the 
 ancients, led by Democritus, and afterwards 
 by Epicurus, maintained that all the quali- 
 ties of bodies which the moderns call se- 
 condary qualities— to wit, smell, taste, sound, 
 colour, heat, and cold— are mere illusions of 
 sense, and have no reA existence.* Plato 
 maintained tliat we can attain no real know- 
 ledge of material things ; and that eternal 
 and immutable ideas are the only objects of 
 real knowledge. The academics and scep- 
 tics anxiously sought for arguments to 
 prove the fallaciousness of our senses, in 
 order to support their favourite doctrine, 
 
 * Not correctly stated. See above, p. SIB, note S. 
 J he Epicureans denied the fallacy of .Sense.—H. 
 
 that even in things that seem most evident, 
 we ought to withhold assent. [289J 
 
 Among the Peripatetics we find frequent 
 complaints that the senses often deceive us, 
 and that their testimony is to be suspected, 
 when it is not confirmed by reason, by which 
 the errors of sense may be corrected. This 
 complaint they supported by many com- 
 monplace instances : such as, the crooked 
 appearance of an oar in water; objects being 
 magnified, and their distance mistaken, in 
 a fog ; the sun and moon appearing about 
 a foot or two in diameter, while they are 
 really thousands of miles ; a square tower 
 being taken at a distance to be round. These, 
 and many similar appearances, they thought 
 to be sufficiently accounted for from the 
 fallacy of the senses : and thus the fallacy 
 of the senses was used as a decent cover to 
 conceal their ignorance of the real causes of 
 such phsenomeua, and served the same pur- 
 pose as their occult qualities and substantial 
 forms. • 
 
 Des Cartes and his followers joined in 
 the same complaint. Antony le Grand, a 
 philosopher of that sect, in the first chapter 
 of his Logic, expresses the sentiments of 
 the sect as follows : " Since all our senses are 
 fallacious, and we are frequently deceived 
 by them, common reason advises that we 
 should not put too much trust-in them, nay, 
 that we should suspect falsehood in every- 
 thing they represent ; for it is imprudence 
 and temerity to trust to those who have but 
 once deceived us; and, if they err at anytime, 
 they may be believed always to err. They 
 are given by nature for this purpose only 
 to warn us of what is useful and what is 
 hurtful to us. The order of Nature is per- 
 verted when we put them to any other 
 use, and apply them for the knowledge of 
 truth." 
 
 When we consider that the active part 
 of mankind, in all ages from the beginning 
 of the world, have rested their most import- 
 ant concerns upon the testimony of sense, 
 it will be very difficult to reconcile their 
 conduct with the speculative opinion so 
 generally entertained of the fallaciousness 
 of the senses. [290] And it seems to be 
 a very unfavourable account of the work- 
 manship of the Supreme Being, to think 
 that he has given us one faculty to deceive 
 us — to wit, our senses ; and another faculty 
 — to wit, our reason — to detect the fallacy. 
 
 It deserves, therefore, to be considered, 
 whether the fallaciousness of our senses be 
 not a common error, which men have been 
 led into, from a desire to conceal their igno- 
 rance, or to apologize for their mistakes. 
 
 There are two powers which we owe to 
 
 * A very inaccurate representation of the Peripa. 
 tetic doctrine touching this matter. In fact, the Ari. 
 stotelian doctrine, and that ot Reid himself, are 
 almost the same.— H. 
 
 [288-290]
 
 OHAP. XXII.] OF thp: fallacy of the senses. 
 
 335 
 
 our external senses— sensation, and the per- 
 ception of external objects. 
 
 It is impossible that there can be any 
 fallacy in sensation : for we are conscious of 
 all our sensations, and tliey can neither be 
 any other in their nature, nor greater or 
 less in their degree than we feel them. It 
 is impossible that a man should be in pain, 
 when he does not feel pain ; and when he 
 ftels pain, it is impossible that his pain 
 should not be real, and in its degree what 
 it is felt to be ; and the same thing may be 
 said of every sensation whatsoever. An 
 agreeable or an uneasy sensation may be 
 forgot when it is past, but when it is pre- 
 sent, it can be nothing but what we feel. 
 
 If, therefore, there be any fallacy in our 
 senses, it must be in tlie perception of ex- 
 ternal objects, which we shall next con- 
 sider. 
 
 And here I grant that we can conceive 
 powers of perceiving external objects more 
 perfect than ours, which, possibly, beings of a 
 higher order may enjoy. We can perceive 
 external objects only by moans of bodily or- 
 gans ; and these are liable to various dis- 
 orders, which sometimes affect our powers 
 of perception. The nerves and brain, which 
 are interior organs of perception, are like- 
 wise liable to disorders, as every part of the 
 human frame is. [291] 
 
 The imagination, the memory, the judging 
 and reasoning powers, are all liable to be 
 hurt, or even destroyed, by disorders of the 
 tiody, as well as our powers of percepti'ii ; 
 bu: we do not on this account call them 
 fallacious. 
 
 Our senses, our memory, and our reason, 
 are all limited and imperfect — this is the 
 lot of humanity : but they are such as the 
 Author of our being saw to be best fitted 
 fur us in our present state. Superior natures 
 may have intellectual powers which we have 
 not, or such as we have, in ii more perfect 
 degree, and less liable to accidental disor- 
 ders ; but we have no reason to think that 
 God has given fallacious powers to any of 
 nis creatures : this would be to think dis- 
 honourably of our Maker, and would lay a 
 foundation for universal scepticism. 
 
 The appearances commonly imputed to 
 the fallacy of the senses are many and of 
 different kinds; but I think they may be 
 reduced to the four following classes. 
 
 First, Many things called deceptions of 
 the senses are-only conclusions rashly drawn 
 from the testimony of the senses. In these 
 c; ses the testimony of the senses is true, 
 but we rashly draw a conclusion from it, 
 whicii dues not necessarily follow. Wcjiro 
 dis[)os((l to inijiutc our trmrs ratiier to false 
 information than to inconclusive reasoning, 
 and to bianie our senses for the wrong con- 
 clusions we draw from their testimony. 
 
 Thus, when a man has taken a counter - 
 [291-^93] 
 
 feit guinea for a true one, he says his senses 
 deceived him ; but he lays the blame where 
 it ought not to be laid : for we may ask him, 
 Did your senses give a false testimony of 
 the colour, or of the figure, or of the im- 
 pression ? No. But this is all that they 
 testified, and this they testified truly : From 
 these premises you concluded that it was a 
 true guinea, but this conclusion does not 
 follow ; you erred, therefore, not by relying 
 upon the testimony of sense, but by judging 
 rashly from its testimony. [292] Not only 
 are your senses innocent of this error, but 
 it is only by their information that it can be 
 discovered- If you consult thcni properly, 
 they will inform you that what you took for 
 a guinea is base metal, or is deficient in 
 weight, and this can only be known by the 
 testimony of sense. 
 
 I remember to have met with a man who 
 thought the argument used by Protestants 
 against the Popish doctrine of transubstan- 
 tiation, from the testimony of our senses, 
 inconclusive ; because, said he, instances 
 may begivenwhere severalof our senses may 
 deceive us": How do we know then that 
 there may not be cases wherein they all 
 deceive us, and no sense is left to detect the 
 fallacy ? I begged of him to know an in- 
 stance wherein several of our senses deceive 
 us. I take, said he, a piece of soft turf ; I 
 cut it into the shape of an ajiple ; with the 
 essence of apples, I give it the smell of an 
 apple ; and with paint, I can give it the skin 
 and colour of an apple. Here then is a body, 
 which, if you judge by your eye, by your 
 touch, or by your smell, is an apple. 
 
 To this I would answer, that no one of 
 our senses deceives us in this case. 'My 
 sight and touch testify that it has the shape 
 ar.d colour of an apple : this is tn e. The 
 sense of smelling testifies that it has the 
 smell of an apple : this is likewise true, and 
 is no deception. Where then lies the de- 
 ception ? It is evident it lies in this — that 
 because this body has some qualities belong- 
 ing tc'.an ajiple I conclude that it is an apple. 
 Tins is a fallacy, not of the senses, but of 
 inconclusive -reasoning. 
 
 Many false judgments that are accounted 
 deceptions of sense, arise from our mistaking 
 relative motion for real or absolute motion. 
 These can be no deceptions of sense, because 
 by our senses we perceive only the relative 
 motions of bodies ; and it is by reasoning 
 that we infer the real from the relative which 
 we perceive- A littlcTctlection may satisfy 
 URoftiiis. [29;j) 
 
 It was liefore observed, that we ]>erceive 
 extension to be one sensilile (|uality of 
 bodies, and thence are necessarily led to 
 conceive space, though space be of itself 
 no oliject of sense. When a body is re- 
 moved out of its place, the si)ace which it 
 filled remains empty till it is filled by somo
 
 336 
 
 ON THE INTELLECTUAL POWERS. 
 
 [essay II. 
 
 other body, and would remain if it should 
 never Ic filled. Before any body existed, the 
 space which bodies now occupy was emjity 
 space, capable of receiving bodies ; for no 
 body can exist where there is no space to 
 contain it. Tliere is space therefore where- 
 ever bodies exist, or can exist. 
 
 Hence it is evident that space can have 
 no limits. It is no less evident that it is 
 immovable. Bodies placed in it are mov- 
 able, but the place where they were cannot 
 be moved ; and we cau as easily conceive a 
 thing to be moved from itself, as one part 
 of space brought nearer to or removed 
 farther from another. 
 
 The space, therefore, which is imlimited 
 and immovable, is called by jjhilosophers 
 absolu'e space. Absolute or real motion is 
 a change of place in absolute space. 
 
 Our senses do not testify the absolute 
 motion or absolute rest of any body. When 
 one body removes from another, this may 
 be discerned by the senses ; but whether 
 any body keeps the same part of absolute 
 space, we do not perceive by our senses. 
 When one body seems to remove from an- 
 other, we can infer with certainty that there 
 is absolute motion, but whether in the one 
 or the other, or partly in both, is not dis- 
 cerned by sense. 
 
 Of all the prejudices which philosophy 
 contradicts, I believe there is none so general 
 as that the earth keeps its place uinnoved. 
 This opinion seems to be universal, till it 
 is corrected by instruction or by philoso- 
 phical speculation. Those who have any 
 tincture of education are not now in danger 
 of being held by it, but they find at first a 
 reluctance to believe that there are anti- 
 podes ; that the earth is spherical, and turns 
 round its axis every day, and round the sun 
 every year : they can recollect the time 
 when reason struggled with prejudice upon 
 these points, and prevailed at length, but 
 not without some effort. [294] 
 
 The cause of a prejudice so very general 
 is not unworthy of investigation. But that 
 is not our present business. It is sufficient 
 to observe, that it cannot justly be called a 
 fallacy of sense ; because our senses testify 
 only the change of situation of one body in 
 relation to other bodies, and not its change 
 of situation in absolute space. It is only 
 the relative motion of bodies that we per- 
 ceive, and that we perceive truly. It is 
 the province of reason and philosophy, from 
 the relative motions which we perceive, to 
 collect the real and absolute motions which 
 produce them. 
 
 All motion must be estimated from some 
 point or place which is supposed to be at 
 rest. We perceive not the points of abso- 
 lute space, from which real and absolute 
 motion must be reckoned ; And there are 
 obvious reasons that lead mankind in the 
 
 state of ignorance, to make the earth the 
 fixL-d place from which they may estimate 
 the various motions they perceive. The 
 custom of doing this from infancy, and of 
 using constantly a language which supposes 
 the earth to be at rest, may perhaps be the 
 cause of the general prejudice in favour of 
 this opinion. 
 
 Tims it appears that, if we distinguish 
 accurately between what our senses really 
 and naturally testify, and the conclusions 
 which we draw from their testimony by 
 reasoning, we shall find many of the errors, 
 called fallacies of the senses, to be no fal- 
 lacy of the senses, but rash judgments, 
 which are not to be imputed to our senses. 
 
 Secondly, Another class of errors imputed 
 to the fallacy of the senses, are those which 
 we are liable to in our acquired perceptions. 
 Acquired perception is not properly the 
 testimony of those senses which God hath 
 given us, but a conclusion drawn from what 
 the senses testify. [205] In our past ex- 
 perience, we have found certain things con- 
 joined with what our senses testify. We 
 are led by our constitution to expect this 
 conjunction^w^ime to come ; and when 
 we have of^n found it in our experience to 
 happen, we acquire a firm belief that the 
 things which we have found thus conjoined, 
 are connected in nature, and that one is a 
 sign of the other. The appearance of the 
 sign immediately produces the belief of its 
 usual attendant, and we think we perceive 
 the one as well as the other. 
 
 That such conclusions are formed even 
 in infancy, no man can doubt : nor is it less 
 certain that they are confounded with the 
 natural and immediate perceptions of sense, 
 and in all languages are called by the same 
 name. We are therefore authorized by 
 language to call them perception, and must 
 often do so, or speak unintelligibly. But 
 philosophy teaches us, in this, as in many 
 other instances, to distinguish things which 
 the vulgar confound. I have therefore 
 given the name of acquired perception to 
 such conclusions, to distinguish them from 
 what is naturally, originally, and inmie- 
 diately testified by our senses. Whether 
 this acquired perception is to be resolved 
 into some process of reasoning, of which 
 we have lost the remembrance, as some 
 philosophers think, or whether it results 
 from some part of our constitution distinct 
 from reason, as I rather believe, does not 
 concern the present subject. If the first 
 of these opinions be true, the errors of ac- 
 quired perception ■will fall under the first 
 class before mentioned. If not, it makes 
 a distinct class by itself But whether the 
 one or the other be true, it must be 
 observed that the errors of acquired per- 
 ception are not properly fallacies of our 
 senses. 
 
 [294. 2951
 
 CHAP. XXII.] OF THE FALL.ACY OF THE SENSES. 
 
 337 
 
 Thus, wheu a globe is set before me, I 
 perceive by my eyes that it has three di- 
 mensions and a spherical figure. To say 
 that this is not perception, would be to 
 reject the authority of custom in the use of 
 words, which uo wise man will do : but 
 that it is not the testimony of my sense of 
 seeing, every philosopher knows. I see 
 only a circular form, having the light and 
 colour distributed in a certain way over it. 
 [296] But, being accustomed to observe 
 tliis distribution of light and colour only in 
 a spherical body, I immediately, from what 
 1 see, believe the object to be spherical, and 
 say that I see or perceive it to be spherical. 
 When a painter, by an exact imitation of 
 that distribution of light and colour which 
 I have been accustomed to see only in a 
 real sphere, deceives me, so as to make me 
 take that to be a real sphere which is only a 
 painted one, the testimony of my ej e is true 
 — the colour and visible figure of the object 
 is truly what I see it to be : the error lies 
 in the conclusion drawn from what I see — 
 to wit, that the object has three dimensions 
 and a spherical figure. The conclusion is 
 false in this case ; but, whatever be the 
 origin of this conclusion, it is not properly 
 the testimony of sense. 
 
 To this class we must refer the judg- 
 ments we are apt to form of the distance 
 and magnitude of the heavenly bodies, and 
 of terrestrial objects seen on high. The 
 mistakes we make of the magnitude and 
 distance of objects seen through optical 
 glasses, or through an atmosphere uncom- 
 monly clear or uncommonly foggy, belong 
 likewise to this class. 
 
 The errors we are led into in acquired 
 perception are very rarely hurtful to us in 
 the conduct of life ; they are gradually cor- 
 rected by a more enlarged experience, and 
 a more perfect knowledge of the laws of 
 Nature : and the general laws of our con- 
 stitution, by which we are sometimes led 
 into them, are of the greatest utility. 
 
 We come into the world ignorant of 
 everything, and by our ignorance exposed 
 to many dangers and to many mistakes. The 
 regular train of causes and effects, which 
 divine wisdom has established, and which 
 directs every step of our conduct in advanced 
 life, is unknown, until it is gradually dis- 
 covered by experience. [207] 
 
 We must learn much from experience 
 before we can reason, ami therefore must be 
 \iable to many errors. Indeed, I apprehend, 
 tiiat, in the first part of life, reason would do 
 us much mure hurt than good- Were we 
 sensible of our condition in that period, anil 
 capable of reflecting upon it, wo snould be 
 like a man in the dark, surrounded with 
 dangers, where every step he takes may be 
 into a pit. Reason would direct him to sit 
 down, and wait till he could see about him. 
 '296-^98 J 
 
 In like manner, if we suppose an infant 
 endowed with reason, it would direct him 
 to do nothing, till he knew what could be 
 done with safety. This he can only know 
 by experiment, and experiments are danger- 
 ous. Reason directs, that experiments that 
 are full of danger should not be made with- 
 out a very urgent cause. It would there- 
 fore make the infant unhappy, and hinder 
 his improvement by experience. 
 
 Nature has followed another plan. The 
 child, unapprehensive of danger, is led by 
 instinct to exert all his active powers, to 
 try everything without the cautious admo- 
 nitions of reason, and to believe everything 
 that is told him. Sometimes he suffers by 
 his rashness what reason would have pre- 
 vented : but his suffering proves a salutary 
 discipline, and makes him for the future 
 avoid the cause of it. Sometimes he is 
 imposed upon by his credulity ; but it is of 
 infinite benefit to him upon the whole. His 
 activity and credulity are more useful qua- 
 lities and better instructors than reason 
 would be ; they teach him more in a day 
 than reason would do in a year ; they furnish 
 a stock of materials for reason to work upon ; 
 they make him easy and happy in a period 
 of his existence when reason could only 
 serve to suggest a thousand tormenting 
 anxieties and fears : and he acts agreeably 
 to the constitution and intention of nature 
 even when he does and believes what reason 
 would not justify. So that the wisdom and 
 goodness of the Author of nature is no less 
 conspicuous in withholding the exercise of 
 our reason in this period, than in bestowing 
 it when we are ripe for it. [298] 
 
 A third class of errors, ascribed to the 
 fallacy of the senses, proceeds from igno- 
 rance of the laws of nature. 
 
 The laws of nature (I mean not moral 
 but physical laws) are learned, either from 
 our own experience, or the experience of 
 others, who have had occasion to observe 
 the course of nature. 
 
 Ignorance of those laws, or inattention 
 to them, is apt to occasion false judgments 
 with regard to the objects of seiise, especial- 
 ly those of hearing and of sight ; which 
 false judgments are often, without good 
 reason, called fallacies of sense. 
 
 Sounds affect the ear ditlVrontly, accord- 
 ing as the sounding body is before or behind 
 us, on the right hand or on the left, near or 
 at a great distance. We learn, by the 
 manner in which the sound affects the ear, 
 on what hand we are to look for the sound- 
 ing body ; and in most cases we judge right. 
 Hut we are sometimes deceived by echoes, 
 or by whispering galleries, or si>eaking 
 trumpets, wliicli return the sound, or alter 
 its direction, or convi'V It to a distance with- 
 out diniinutioM. 
 
 The deception ia still greater, becau»«
 
 338 
 
 ON THE INTELLECTUAL POWERS. 
 
 LeSSAY II. 
 
 more uncommon, which is said to be pro- 
 duced by Gastriloquists — that is, persons 
 who have acquired the art of modifying 
 their voice, so that it shall affect the ear of the 
 Vearers, as if it came from another person, 
 or from the clouds, or from under the earth 
 
 1 never had the fortune to be acquainted 
 with any of these artists, and therefore can- 
 not say to what degree of perfection the art 
 may have bt en carried. 
 
 I apprehend it to be only such an im- 
 perfect imitation as may deceive those who 
 are inattentive, or under a panic. For, if 
 it could be carried to perfection, a Gastrilo- 
 quist would be as dangerous a man in so- 
 ciety as was the shepherd Gyges,* who, by 
 turning a ring upon his finger, could make 
 himself invisible, and, by that means, from 
 being the king's shepherd, became King of 
 Lydia. [299] 
 
 If the Gastriloquists have all been too 
 good men to use their talent to the detri- 
 ment of others, it might at least be expected 
 that some of them should apply it to their 
 own advantage. If it could be brought to 
 any considerable degree of perfection, it 
 seems to be as proper an engine for draw- 
 ing money by the exhibition of it, as leger- 
 demain or rope-dancing. But I have never 
 heard of any exhibition of this kind, and 
 therefore am apt to think that it is too 
 coarse an imitation to bear exhibition, even 
 to the vulgar. 
 
 Some are said to have the art of imitat- 
 ing the voice of another so exactly that in 
 the dark they might be taken for the person 
 whose voice they imitate. I am apt to 
 think that this art also, in the relations 
 made of it, is magnified beyond the truth, as 
 wonderful relations are apt to be, and that 
 an attentive ear would be able to distinguish 
 the copy from the original. 
 
 It is indeed a wonderful instance of the 
 accuracy as well as of the truth of our senses, 
 in things that are of real use in life, that we 
 are able to distinguish all our acquaintance 
 by their countenance, by their voice, and 
 fcy their handwriting, when, at the same 
 time, we are often unable to say by what 
 minute difference the distinction is made ; 
 and that we are so very rarely deceived in 
 matters of this Jcind, when we give proper 
 attention to the informations of sense. 
 
 However, if any case should happen, in 
 which sounds produced by different causes 
 are not distinguishable by the ear, this may 
 prove that our senses are imperfect, but not 
 that they are fallacious. The ear may not 
 be able to draw the just conclusion, but it 
 is only our ignorance of the laws of sound 
 that leads us to a wrong conclusion. [300] 
 
 Deceptions of sight, arising from igno- 
 
 » See Cicero, De Officiis. The story told by Hero, 
 dotu* is different. — H. 
 
 ranee of the laws of nature, are more numer- 
 ous and more remarkable than those of 
 hearing. 
 
 The rays of light, which are the means 
 of seeing, pass in right lines from the object 
 to the eye, when they meet with no obstruc- 
 tion ; and we are by nature led to conceive 
 the visible object to be in the direction of 
 the rays that come to the eye. But the 
 rays may be reflected, refracted, or inflected 
 in their passage from the object to the eye, 
 according to certain fixed laws of nature, 
 by which means their direction may be 
 changed, and consequently the apparent 
 place, figure, or magnitude of the object. 
 
 Thus, a child seeing himself in a mirror, 
 thmks he sees another child behind the 
 mirror, that imitates all his motions. But 
 even a child soon gets the better of this de- 
 ception, and knows that he sees himself only. 
 
 All the deceptions made by telescopes, 
 microscopes, camera obscuras, magic lau- 
 thorns, are of the same kind, though not so 
 familiar to the vulgar. The ignorant may 
 be deceived by them ; but to those who are 
 acquainted with the principles of optics, 
 they give just and true information ; and the 
 laws of nature by which they are produced, 
 are of infinite benefit to mankind. 
 
 There remains another class of errors, 
 commonly called deceptions of sense, and 
 the only one, as I apprehend, to which that 
 name can be given with propriety : I mean 
 such as proceed from some disorder or pre- 
 ternatural state, either of the external organ 
 or of the nerves and brain, which are in- 
 ternal organs of perception. 
 
 In a delirium or in madness, perception, 
 memory, imagination, and our reasoning 
 powers, are strangely disordered and con- 
 founded. There are liliewise disorders which 
 affect some of our senses, while others are 
 sound. Thus, a man may feel pain in his 
 toes after the leg is cut off. He may feel a 
 little ball double by crossing his fingers. [30 1 ] 
 He may see an object double, by not du-ect- 
 both eyes properly to it. By pressing the 
 ball of his eye, he may see colours that ar« 
 not real. By the jaundice in his eyes, he 
 may mistake colours. These are more 
 properly deceptions of sense than any of the 
 classes before mentioned. 
 
 We must acknowledge it to be the lot of 
 human nature, that all the human faculties 
 are liable, by accidental causes, to be hurt 
 and unfitted for their natural functions, 
 either wholly or in part : but as this imper- 
 fection is common to them all, it gives no 
 just ground for accounting any of them 
 fallacious. 
 
 Upon the whole, it seems to have been a 
 common error of philosophei-s to account 
 the senses fallacious. And to this error 
 they have added another — that one use of 
 reason is to detect the fallacies of sense. 
 
 [299-301]
 
 CHAP. XXII.] OF THE FALLACY OF THE SENSES. 
 
 339 
 
 It appears, I think, from what has been 
 said, that there is no more reason to account 
 our senses fallacious, than our reason, our 
 memory, or any other faculty of judging 
 which nature hath given us. They are all 
 limited and imperfect ; but wisely suited to 
 the present condition of man. We are 
 liable to error and wrong judgment in the 
 use of them all ; but as little in the inform- 
 ations of sense as in the deductions of 
 reasoning. And the errors we fall into with 
 regard to objects of sense are not corrected 
 by reason, but by more accurate attention 
 to the informations we may receive by our 
 senses themselves. 
 
 Perhaps the pride of philosophers may 
 have given occasion to this error. Reason 
 is the faculty wherein they assume a supe- 
 riority to the unlearned. The informations 
 of sense are common to the philosopher and 
 to the most illiterate : they put all men 
 upon a level ; and therefore are apt to be 
 undervalued. We must, however, be be- 
 holden to the informations of sense for the 
 greatest and most interesting part of our 
 
 knowledge. [302 J The wisdom of nature 
 has made the most useful things most com- 
 mon, and they ought not to be despised on 
 that account. Nature likewise forces our 
 belief in those informations, and all the 
 attempts of philosophy to weaken it are 
 fruitless and vain. 
 
 I add only one observation to what has 
 been said upon this subject. It is, that there 
 seems to be a contradiction between what 
 philosophers teach concerning ideas, and 
 their doctrine of the fallaciousness of the 
 senses. We are taught that the office of 
 the senses is only to give us the ideas of 
 external objects. If this be so, there can 
 be no fallacy in the senses. Ideas can 
 neither be true nor false. If the senses 
 testify nothing, they cannot give false testi- 
 mony. If they are not judging faculties, no 
 judgment can be imputed to them, whether 
 false or true. There is, therefore, a contra- 
 diction between the common doctrine con- 
 cerning ideas and that of the fallaciousness 
 of the senses. Both may be false, as I believe 
 they are, but both cannot be true, [303] 
 
 ESSAY III. 
 
 OF MEMORY. 
 
 CHAPTER I. 
 
 THINGS OBVIOUS AND CERTAIN WITH REGARD 
 TO MEMORY. 
 
 In the gradual progress of man, from 
 infancy to maturity, tliere is a certain order 
 in which his faculties are unfolded, and this 
 eeems to be the best order we can follow in 
 treating of them. 
 
 The external senses appear first ; me- 
 mory soon follows — which we are now to 
 consider. 
 
 It is by memory that we have an imme- 
 diate knowledge of things past." The 
 senses give us information of things only as 
 they exist in the present moment ; and this 
 information, if it were not preserved by 
 memory, would vanish instantly, and leave 
 us as ignorant as if it liad never been. 
 
 ^Memory must have an ol)ject. Every 
 man who remembers must remember sonie- 
 
 • An immrrf/a^e knowlcdKeof'a;)flf<UiinR is »con- 
 trailictioii. I(ir wo can (■nlv kuow a thiiiK iniim'. 
 diatcly, if kv knf>w it in itttit, or as cxihlintf ; hut 
 what ih |ia«t catinot he known in ittcll, ti<r Jt ih n(in. 
 I'Xistent. — II. 
 
 [.'{(jy :{()1-] 
 
 thing, and that which he remembers is 
 called the object of his remembrance. In 
 this, memory agrees with perception, but 
 differs from sensation, which has no object 
 but the feeling itself.* [304] 
 
 Every man can distinguish the thing re- 
 membered from the remembrance of it. 
 We may remember anything which we have 
 seen, or heard, or known, or done, or suf- 
 fered ; but the remembrance of it is a par- 
 ticular act of the mind which now exists, 
 and of which we are conscious. To con- 
 found these two is an absurdity, wliich a 
 thinking man could not be led into, but by 
 some false hypothesis which hinders hira 
 from reflecting upon the thing which he 
 would explain by it. 
 
 In memory we do not find such a train 
 of operations connected by our constitution 
 as in perception. When wo perceive an 
 object by our senses, there is, first, some 
 impression made by the oliject ujion tlie 
 organ of sense, eitlicr ininiediatily, or by 
 means of some medium. IJy this, an ini- 
 
 » Hut have we <inly such n tnrili(il>' knowledge of 
 the u-.t\ <ilij(( t in pciccptii'ii, as we liiivi' nl ilir real 
 ohjictin ininiory? On Itiid'B error, li.ijchmg iho 
 ohjfct oiniemory, «re, In general, Noic li.— II.
 
 H40 
 
 ON THE INTELLECTUAL I'OVFERS. 
 
 [essay iu* 
 
 pression is made upon the nerves and brain, 
 in consequence of which we feel some sensa- 
 tion ; and that sensation is attended by tliat 
 conception and beUef of the external object 
 which we call perception. These opera- 
 tions are so connected in our constitution, 
 that it is difficult to disjoin them in our con- 
 ceptions, and to attend to each without con- 
 founding it with the others. But, in the 
 operations of memory, we are free from this 
 embarrassment ; they are easily distin- 
 guished from all other acts of the mind, and 
 the names which denote them are free from 
 all ambiguity. 
 
 The object of memory, or thing remem- 
 bered, must be something that is past ; as 
 the object of perception and of conscious- 
 ness nmst be something which is present. 
 What now is, cannot be an object of 
 memory ; neither can that which is past 
 and gone be an object of perception or of 
 consciousness. 
 
 Memory is always accompanied with the 
 belief of that which we remember, as per- 
 ception is accompanied with the belief of 
 that which we perceive, and consciousness 
 with the belief of that whereof we are con- 
 scious. Perhaps in infancy, or in a disorder 
 of mind, things remembered may be con- 
 founded with those which are merely ima- 
 gined ; but in mature years, and in a sound 
 state of mind, every man feels that he must 
 believe what he distinctly remembers, 
 though he can give no other reason of his 
 belief, but that he remembers the thing dis- 
 tinctly ; whereas, when he merely imagines 
 a thing ever so distinctly, he has no belief 
 of it upon that account. [305] 
 
 This belief, which wo have from distinct 
 memory, we account real knowledge, no 
 less certain than if it was grounded on de- 
 monstration ; no man in his wits calls it in 
 question, or will hear any argument against 
 it.* Tlie testimony of witnesses in causes 
 of life and death depends upon it, and all 
 the knowledge of mankind of past events is 
 built on this foundation. 
 
 There are cases in whicli a man's me- 
 mory is less distinct and determinate, and 
 where he is ready to allow that it may liave 
 failed him ; but this does not in the least 
 weaken its credit, when it is perfectly dis- 
 tinct. 
 
 Memory implies a conception and belief 
 of past duration ; for it is impossible that a 
 man should remember a thing distinctly, 
 without believing some interval of duration, 
 more or less, to have passed between the 
 time it happened, and the presentmoment ; 
 and I think it is impossible to shew how 
 we could acquire a notion of duration if we 
 had no memory. Things remembered 
 must be things formerly perceived or 
 
 * But see lieL.w, p. 362.— H. 
 
 known. I remember the transit of Venus 
 over the sun in the year 1769. I. must 
 therefore have perceived it at the time it 
 happened, otherwise I could not now re- 
 member it. Our first acquaintance with 
 any object of thought cannot be by remem- 
 brance. Memory can only produce a con- 
 tinuance or renewal of a former acquaint- 
 ance with the thing remembered. 
 
 The remembrance of a past event is ne- 
 cessarily accompanied with the conviction 
 of our own existence at the tune the event 
 happened. I cannot remember a thing 
 that happened a year ago, without a con- 
 viction as strong as memory can give, that 
 I, the same identical person who now re- 
 member that event, did then exist. [306] 
 
 What I have hitherto said concerning 
 memory, I consider as principles which ap- 
 pear obvious and certain to every man who 
 will take the pains to reflect upon the oper- 
 ations of his own mind. They are facts of 
 which every man must judge by what he 
 feels ; and they admit of no other proof 
 but an appeal to every man's own reflec- 
 tion. I shall therefore take them for 
 granted in what follows, and shall, first, 
 draw some conclusions from them, and 
 then examine the theories of philoso- 
 phers concerning memory, and concerning 
 duration, and our personal identity, of 
 which we acquire the knowledge by me- 
 mory. 
 
 CHAPTER IL 
 
 MEMORY AN ORIGINAL FACULTY. 
 
 First, I think it appears, that memory 
 is an original faculty, given us by the 
 Author of our being, of which we can give 
 no account, but that we are so made. 
 
 The knowledge which I have of things 
 past, by my memory, seems to me as unac- 
 countable as an immediate knowledge 
 would be of things to come ; * and I can 
 give no reason why I should have the one 
 and not the other, but that such is the will 
 of my Maker. I find in my mind a distinct 
 conception, and a firm belief of a series of 
 past events ; but how this is produced I 
 know not. I call it memory, but this is 
 only giving a name to it — it is not an ac- 
 count of its cause. I believe most firmly, 
 what I distinctly remember ; but I can 
 
 * An immiyliate knowledge of things to come, is 
 equally a contradiction as an ?/?! wed/ate knowledge of 
 things past. See the first note of last page. iJut if, 
 as Keid himself allows, memory depend upon cer- 
 tain enduring affections of the brain, determined by 
 past cognition, it seems a strange assertion, on this 
 as on other accounts, that the possibility of a know- 
 ledge of the future is not more inconceivable than 
 of a knowledge of the past. Maupertuis, howtver, 
 has advanced a similar doctrine; and some, also, of 
 the .idvocatcs of animal magnetism. — H. 
 
 [30.5, .S06l
 
 CHAP. II.] 
 
 MEMORY AN ORIGINAL FACULTY. 
 
 341 
 
 give no reason of this belief. It is the in- 
 spiration of the Almi<;hty that gives me 
 this understanding.* [307] 
 
 Wlien I believe the truth of a mathema- 
 tical axiom, or of a mathematical proposi- 
 tion, I see that it must be so : every man 
 who has the same conception of it sees the 
 same. There is a necessary and an evident 
 connection between the subject and the pre- 
 dicate of the proposition ; and I have all 
 the evidence to support my belief which I 
 can possibly conceive. 
 
 When I believe that I washed my hands 
 and" face this morning, there appears no ne- 
 cessity in the truth of this proposition. It 
 might be, or it might not be. A man may 
 distinctly conceive it without believing it at 
 all. How then do I come to believe it ? I 
 remember it distinctly. This is all I can 
 say. This remembrance is an act of my 
 mind. Is it impossible that this act should 
 be, if the event had not happened ? I con- 
 fess I do not see any necessary connection 
 between the one and the other. If any man 
 can shew such a necessary connection, then 
 I think that belief which we have of what 
 we remember will be fairly accounted for ; 
 but, if this cannot be done, that belief is un- 
 accountable, and we can say no more but 
 that it is the result of our constitution. 
 
 Perhaps it may be said, that the ex- 
 perience we have had of the fidelity of me- 
 mory is a good reason for relying upon its 
 testimony. I deny not that this maybe a 
 reason to those who have had this expe- 
 rience, and who reflect upon it. But I be- 
 lieve there are few who ever thought of this 
 reason, or who found any need of it. It 
 must be some very rare occasion that leads 
 a man to have recourse to it ; and in those 
 who have done so, "the testimony of memory 
 was believed before the experience of its 
 fidelity, and that belief could not be caused 
 by tlie experience which came after it. 
 
 We know some abstract truths, by com- 
 paring the terms of the proposition which 
 expresses them, and perceiving some ne- 
 cessary relation or agreement between them. 
 It is tlms I know that two and three make 
 five ; that the diameters of a circle are all 
 equal. [308] Mr Locke having discovered 
 this source of knowledge, too rashly con- 
 cluded that all human knowledge might be 
 derived from it ; and in this he has been 
 followed very generally — by Mr Hume in 
 particular. 
 
 But I apprehend that our knowledge of 
 the existence of things contingent can never 
 be traced to this source. I know that such 
 a thing exists, or did exist. This know- 
 ledge cannot be derived from the i)ercci)ti()n 
 of a necessary agreement between existence 
 
 * " The irispiration of ihc Almifjiity givclh thcin 
 M ndcrntandiiiK." — Jon. — II. 
 
 [307-.'J{»f)] 
 
 and the thing that exists, because there is 
 no such necessary agreement ; and there- 
 fore no such agreement can be perceived 
 either immediately or by a chain of reason- 
 ing. The thing does not exist necessarily, 
 but by the will and power of him that made 
 it ; and there is no contradiction follows from 
 supposing it not to exist. 
 
 Whence I think it follows, that our know- 
 ledge of the existence of our own thoughts, 
 of the existence of all the material objects 
 about us, and of all past contingencies, 
 must be derived, not from a perception of 
 necessary relations or agreements, but from 
 some other source. 
 
 Our Maker has provided other means for 
 
 giving us the knowledge of these things 
 
 mean's which perfectly answer their end, 
 and produce the effect intended by them. 
 But in what manner they do this, is, I fear, 
 beyond our skill to explain. We know our 
 own thoughts, and the operations of our 
 minds, by a power which we call conscious- 
 ness : but this is only giving a name to this 
 part of our frame. It does not explain its 
 fabric, nor how it produces in us an irre- 
 sistible conviction of its informations. We 
 perceive material objects and their sensible 
 qualities by our senses ; but how thej' give 
 us this information, and how they produce 
 our belief in it, we know not. We know 
 many past events by memory ; but how it 
 gives this information, I believe, is inex- 
 plicable. 
 
 It is well known what subtile disputes 
 were held through all the scholastic ages, 
 and are still carried on about the prescience 
 of the Deity. [309] Aristotle had taught 
 that there can be no certain foreknowledge 
 of things contingent ; and in this he has 
 been very generally followed, upon no other 
 grounds, as I apprehend, but that we can- 
 not conceive how such things should be 
 foreknown, and therefore conclude it to be 
 impossible. Ilcnce has arisen an opposi- 
 tion and supposed inconsistency between 
 divine prescience and human liberty. Some 
 have given up the first in favour of the last, 
 and others have given up the last in order 
 to support the fir.st. 
 
 It is remarkable that these disputants 
 have never ai>preliended that there is any 
 difficulty in reconciling with liljcrty the 
 knowledge of what is past, but only (if what 
 is future. It is prescience only, and not 
 memory, that is supposed to be hostile to 
 liberty, and hardly reconciU-able to it. 
 
 Yet I believe the difficulty is perfectly 
 equal in the one case and in the other. I 
 admit, that we cannot account for jiro.science 
 of tlic actions of a free agent. Ibit I main- 
 tain that we can as littler aecouiit for me 
 mory of the past aclioiis of a froi' ageiif, 
 If any man Ihiidis he can prove that the 
 acti(jns of a free agent c.innot he foreknown.
 
 342 
 
 ON THE INTELLECTUAL POWERS. 
 
 [essay 
 
 III. 
 
 he will find the same arguments of equal 
 force to prove that the past actions of a free 
 agent cannot be remembered.* It is true, 
 that what is past did certainly exist. It is 
 no less true that what is future will cer- 
 tainly exist. I know no reasoning from the 
 constitution of the agent, or from his cir- 
 cumstances, that has not equal strength, 
 whether it be applied to his past or to his 
 future actions. The past was, but now is 
 not. The future will be, but now is not. 
 The present is equally connected or un- 
 connected with both. 
 
 The only reason why men have appre- 
 hended so great disparity in cases so per- 
 fectly like, I take to be this. That the faculty 
 of memory in ourselves convinces us from 
 fact, that it is not impossible that an in- 
 telligent being, even a finite being, should 
 have certain knowledge of past actions of 
 free agents, without tracing them from any- 
 thing necessarily connected with them. 
 [310] But having no prescience in our- 
 selves corresponding to our memory of what 
 is past, we find great difficulty in admitting 
 it to be possible even in the Supreme 
 Being. 
 
 A faculty which we possess in some de- 
 gree, we easily admit that the Supreme 
 Being may possess in a more perfect degree ; 
 but a faculty which has nothing corre- 
 sponding to it in our constitution, we will 
 hardly allow to be possible. We are so 
 constituted as to have an intuitive know- 
 leiige of many things past ; but we have no 
 intuitive knowledge of the future. -f- We 
 might perhaps have been so constituted as 
 to have an intuitive knowledge of the future ; 
 but not of the past ; nor would this consti- 
 tution have been more unaccountable than 
 the present, though it might be much more 
 inconvenient. Had this been our consti- 
 tution, we should have found no difficulty 
 in admitting that the Deity may know all 
 things future, but very much in admitting 
 his knowledge of things that are past. 
 
 Our original faculties are all unaccount- 
 able. Of these memory is one. He only 
 •who madethem, comprehends fully how they 
 are made, and how they produce in us not 
 only a conception, but a firm belief and 
 assurance of things which it concerns us to 
 know. 
 
 * This is a marvellous doctrine The difficulty in 
 the two cases is not the same. The past, as past, 
 whether it has been Iheaction of a free agent or not, 
 is noiv necessary ; and, though we may be unable to 
 understand how it can be remembered, the supposi. 
 tion of-its remembrance involves no contradiction. 
 On the contrary, the future action of a free agent is 
 ex hypothesi not a necessary event. Kut an event 
 cannot be now certainly foreseen, except it is now 
 certainly to be; and to say that what is certainli/ to be 
 is not necessarily to be, stems a contradiction. — H. 
 
 t If by intuitive be meant immediate, such a know, 
 ledge n impossiblein either case ; for we can know 
 neither the pa.** nor the futiire'm themselves, but 
 only in ihe present — that i<, mediately.— H. 
 
 CHAPTER in. 
 
 OF DURATION. 
 
 From the principles laid down in the 
 first chapter of this Essay, I think it appears 
 that our notion of duration, as well as our 
 belief of it, is got by the faculty of memory. * 
 It is essential to everything remembered 
 that it be something which is past ; and we 
 cannot conceive a thing to be past, without 
 conceiving some duration, more or less, be- 
 tween it and the present. [311] As soon 
 therefore as we remember anything, we 
 must have both a notion and a "belief of 
 duration. It is necessarily suggested by 
 every operation of our memory ; and to that 
 faculty it ought to 'be ascribed. This is, 
 therefore, a proper place to consider what 
 is known concerning it. 
 
 Duration, Extension, and Number, are 
 the measures of all things subject to men- 
 suration. When we apply them to finite 
 things which are measured by them, they 
 seem of all things to be the most distinctly 
 conceived, and most within the reach of 
 human understanding. 
 
 Extension having three dimensions, has 
 an endless variety of modifications, capable 
 of being accurately defined ; and their 
 various relations furnish the human mind 
 with its most ample field of demonstrative 
 reasoning. Duration having only one di- 
 mension, has fewer modifications ; but these 
 are clearly understood — and their relations 
 admit of measure, proportion, and demon- 
 strative reasoning. 
 
 Number is called discrete quantity, be- 
 cause it is compounded of units, which are 
 all equal and similar, and it can only be 
 divided into units. This is true, in some 
 sense, even of fractions of unity, to which 
 we now commonly give the name of num- 
 ber. For, in every fractional number, the 
 unit is supposed to be subdivided into a 
 certain number of equal parts, which are 
 the units of that denomination, and the 
 fractions of that denomination are only di- 
 visible into units of the same denomination. 
 Duration and extension are not discrete, 
 but continued quantity. They consist of 
 parts perfectly similar, but divisible without 
 end. 
 
 In order to aid our conception of the mag- 
 nitude and proportions of the various inter- 
 vals of duration, we find it necessary to give 
 a name to some known portion of it, such 
 as an hour, a day, a year. These we con- 
 sider as units, and, by the number of them 
 contained in a larger interval, we form a 
 distinct conception of its magnitude. [312] 
 A similar expedient we find necessary to give 
 
 * Reid thus apparently'makes 27me an empirical 
 or generalized notion H. 
 
 [;310-312]
 
 CHAP, 
 
 III.] 
 
 OF DURATION. 
 
 343 
 
 us a distinct conception of the magnitudes 
 and proportions of things extended. Thus, 
 number is found necessary, as a common 
 measure of extension and duration. But 
 this perhaps is owing to tlic weakness of our 
 understanding. It has even been disco- 
 vered, by the sagacity of mathematicians, 
 that this expedient does not in all cases 
 answer its intention. For there are pro- 
 portions of continued quantity, which can- 
 not be perfectly expressed by numbers ; 
 such as that between the diagonal and side 
 of a square, and many others. 
 
 The parts of duration have to other parts 
 of it the relations of prior and posterior, 
 and to the present they have the relations 
 of past and future. The notion of past is 
 immediately suggested by memory, as has 
 been before observed. And when we have 
 got the notions of present and past, and of 
 prior and posterior, we can from these 
 frame a notion of the future ; for the future 
 is that which is posterior to the present. 
 Nearness and distance are relations equally 
 applicable to time and to place. Distance in 
 time, and distance in place, are things t-o 
 different in their nature and so like in their 
 relation, that it is difficult to determine 
 whether the name of distance is applied to 
 both in the same, or an anological sense. 
 
 The extension of bodies which we per- 
 ceive by our senses, leads us necessarily to 
 the conception and belief of a space which 
 remains immoveable when the body is re- 
 moved. And the duration of events which 
 we remerftber leads us necessarily to the 
 conception and belief of a duration which 
 would have gone on uniformly though the 
 event had never happened. * 
 
 Without space there can be nothing that 
 IS extended. And without time there 
 can be nothing that hath duration. This I 
 thiijk undeniable ; and yet we find that ex- 
 tension and duration are not more clear and 
 intelligible than space and time are dark and 
 difficult objects of contemplation, ['il-i] 
 
 As there must be space wherever any- 
 thing extended does or can exist, and time 
 
 ♦ If Space and Time be necessary ^encralizationi 
 from experience, lliis is contrary to Keid's own doc- 
 trine, that experience can give us no nccessaty know. 
 ledge. If, again, they be iifccssaryntid oritjinal 
 notions, the account of their origin here {jiven, is in. 
 correct. It^should have been said that experience is 
 not the iource of their txliitence, but only the occrt- 
 tion of their manifestalion. On this subject, see, 
 inslar nmnimn, Couein on Locke, i i his " ('"urs 
 de Philosophie," (t. ii., I.cfjnns 17 and. IH.) liiis 
 admirable work has been well transla'ed into lOng- 
 lish, by an American, philosopher, Mr Henry; but 
 the eloquence and precision of tlie author Cin only 
 be properly apprecia'ed by those who study the work 
 in the oriftinal language. '1 he reader may, however, 
 consult likewise Slewart's " l'hilo>opliical Kssavs." 
 (Kssay ii.,'chap. 'J,) ^nd Itoyer Collard's " Krag. 
 meii'f ," (IX. and x.) 'these authors, from their mo'e 
 limitc<l acquaintance witli the sueculations of the f)er. 
 man philosopher", are, however, lesson a level with 
 the problem. — H. 
 
 l?.\3, .31 ij 
 
 when there is or can be anything that has 
 duration, we can set no bounds to either, 
 even in our imagination. They defy all 
 limitation. The one swells in our concep- 
 tion to immensity, the other to eternity. 
 
 An eternity piist is an object which we 
 cannot comprehend ; but a beginning of 
 time, unless we take it in a figurative sense, 
 is a contradiction. By a common figure of 
 speech, we give the name of time to those 
 motions and revolutions by which we mea- 
 sure it, such as days and years. We can 
 conceive a beginning of these sensible mea- 
 sures of time, and say that there was a time 
 when they were not, a time undistinguished 
 by any motion or change ; but to say that 
 there was a time before all time, is a con- 
 tradiction. 
 
 All limited duration is comprehended in 
 time, and all limited extension in space. 
 The^e, in their capacious womb, contain all 
 finite existences, but are contained by none. 
 Created things have their particular place 
 in space, and their particular place in time; 
 buttime is everywhere, and spaceatalltiraes. 
 They embrace each the other, and have that 
 mysterious union which the schoolmen con- 
 ceived between soul and body. The whole 
 of each is in every part of the other. 
 
 We are at a loss to what category or class 
 of things we ought to refer them. They 
 are not beings, but rather the receptacles 
 of every created being, without which it 
 could not have had the possibility of exist- 
 ence. Philosophers have endeavoured to 
 reduce all the objects of human thought to 
 these three classes, of substances, modes, 
 and relations. To which of them shall we 
 refer time, space, and number, the most 
 common objects of thought ? [314] 
 
 Sir Isaac Newton thought that the Deity, 
 by existing everywhere and at all times, 
 constitutes time and space, immensity and 
 eternity. Tliis probably suggested to his 
 great friend, Dr Clarke, what ho calls the 
 argument a priori for the existence of an 
 inniien.se and eternal Being. Space and 
 time, he thought, are only abstract or par- 
 tial conceptions of an immensity and eter- 
 nity which forces itself upon our belief. 
 And as immensity and eternity are not 
 substances, they must be the attributes of a 
 Being who is necessarily inmiense and 
 eternal. These are the speculations of men 
 of superior geniu.s. Btit whether they be 
 as solid as they are sublime, or whether 
 they be the wanderings of iiiiagiii.-ition in a 
 region beyond the limits of human under- 
 standing, I am unable to determine. 
 
 The schoolmen made eternity to be a 
 iiinic stalls — that is, a moment of tiiiio that 
 stands .still. 'I'liis was to put a spoUo into 
 the wheel of time, and might give satisfac- 
 tion (o tli'iHc who are to be .satisfied by 
 words without meaning. But I can as
 
 344 
 
 ON THE INTELLECTUAL POWERS. 
 
 [essay III 
 
 easily believe a circle to be a square as 
 time to stand still. 
 
 Such paradoxes and riddles, if I may so 
 call them, men are involuntarily led into 
 when tliey reason about time and space, 
 and attempt to comprehend their nature. 
 They are probably things of which the hu- 
 man faculties give an imperfect and inade- 
 quate conception. Hence difficulties arise 
 which we in vain attempt to overcome, and 
 doubts which we are unable to resolve. 
 Perhaps some faculty which we possess not, 
 is necessary to remove the darkness which 
 hangs over them, and makes us so apt to 
 bewilder ourselves when we reason about 
 them. [315] 
 
 CHAPTER IV. 
 
 OF IDENTITY. 
 
 The conviction which every man has of 
 his Identity, as far back as his memory 
 reaches, needs no aid of philosophy to 
 strengthen it ; and no philosophy can weaken 
 it, without first producing some degree of 
 insanity. 
 
 The philosopher, liowever, may very 
 properly consider this conviction as a phse- 
 nomenon of human nature worthy of his 
 attention. If he can discover its cause, an 
 addition is made to his stock of knowledge. 
 If not, it must be held as a part of our ori- 
 ginal constitution, or an effect of that con- 
 stitution produced in a manner unknown 
 to us. 
 
 We may observe, first of all, that this con- 
 viction is indispensably necessary to all ex- 
 ercise of reason. The operations of reason, 
 whether in action or in speculation, are 
 made up of successive parts. The antece- 
 dent are the foundation of the consequent, 
 and, without the conviction that the ante- 
 cedent have been seen or done by me, I 
 could have no reason to proceed to the con- 
 sequent, in any speculation, or in any 
 active project whatever. 
 
 There can be no memory of what is past 
 without the conviction that we existed at 
 the time remembered. There may be good 
 arguments to convince me that I existed 
 before the earliest thing I can remember ; 
 but to suppose that my memory reaches a 
 moment farther back than my belief and 
 conviction of my existence, is a contradic- 
 tion. 
 
 The moment a man loses this conviction, 
 as if he had drunk the water of Lethe, past 
 things are done away ; and, in his own 
 belief, he then begins to exist. [316] 
 Whatever was thought, or said, or clone, 
 or suffered before that period, may belong 
 to some other person ; but he can never 
 impute it to himself, or take any subse- 
 
 quent step that supposes it to be his do- 
 ing. 
 
 From this it is evident that we must 
 have the conviction of our own continued 
 existence and identity, as soon as we are 
 capable of thinking or doing anything, on 
 account of what we have thdught, or done, 
 or suffered before ; that is, as soon as we 
 are reasonable creatures. 
 
 That we may form as distinct a notion as 
 weareableof this phenomenon of the human 
 mind, it is proper to consider what is meant 
 by identity in general, what by our own 
 personal identity, and how we are led into 
 that invincible belief and conviction which 
 every man has of his own personal identity, 
 as far as his memory reaches. 
 
 Identity in general, I take to be a rela- 
 tion between a thing which is known to 
 exist at one time, and a thing whicli is 
 known to have existed at another time.* 
 If you ask whether they are one and the 
 same, or two different things, every man of 
 common sense understands the meaning of 
 your question perfectly. Whence we may 
 infer with certainty, that every man of 
 common sense has a clear and distinct no- 
 tion of identity. 
 
 If you ask a definition of identity, I con- 
 fess I can give none ; it is too simple a no- 
 tion to admit of logical definition. I can 
 say it is a relation ; but I cannot find words 
 to express the specific difference between 
 this and other relations, though I am in no 
 danger of confounding it with any other. 
 I can say that diversity is a contrary rela- 
 tion, and that similitude and dissimilitude 
 are another couple of contrary relations, 
 which every man easily distinguishes in his 
 conception from identity and diversity. 
 [317] 
 
 I see evidently that identity supposes 
 an uninterrupted continuance of existence. 
 That which hath ceased to exist, cannot be 
 the same with that which afterwards begins 
 to exist ; for this would be to suppose a 
 being to exist after it ceased to exist, and 
 to have had existence before it was produced, 
 which are manifest contradictions. Con- 
 tinued uninterrupted existence is therefore 
 necessarily implied in identity. 
 
 Hence we may infer that identity cannot, 
 in its proper sense, be applied to our pains, 
 our pleasures, our thoughts, or any opera- 
 tion of our minds. The pain felt this day 
 is not the same individual pain which I felt 
 yesterday, though they may be similar in 
 kind and degree, and have the same cause. 
 The same may be said of every feeling and 
 of every operation of mind : they are all 
 
 * Identity it a relation between our cognitions of 
 a thing, and not between^.things thennelves. It 
 would, therefore, have been better in this sentence to 
 have said, " a relationsoetween a thing as known to 
 exist at one time, and a thing as known to exist at 
 another time." — H. 
 
 [315-317]
 
 CHAP. IV.3 
 
 OF IDENTITY. 
 
 345 
 
 successive in their nature, like time itself, 
 no two moments of which can be the same 
 moment. 
 
 It is otherwise with the parts of absolute 
 space. They always are, and were, and 
 will be the same. So far, I think, we pro- 
 ceed upon clear ground in fixing the notion 
 of identity in general. 
 
 It is, perhaps, more difficult to ascertain 
 with precision the meaning of Personality; 
 but it is not necessary in the present sub- 
 ject : it is sufficient for our purpose to 
 observe, that all mankind place their per- 
 sonality in something that cannot be divided, 
 or consist of parts. A part of a person is 
 a manifest absurdity. 
 
 When a man loses his estate, his health, 
 his strength, he is still the same person, 
 and has lost nothing of his personality. If 
 he has a leg or an arm cut off, he is the 
 same person he was before. The amputated 
 member is no part of his person, otherwise 
 it would have a right to a part of his 
 estate, and be liable for a part of his en- 
 gagements ; it would be entitled to a share of 
 his merit and demerit — which is manifestly 
 absurd. A person is something indivisible, 
 and is what Leibnitz calls a monad. [318] 
 
 My personal identity, therefore, implies 
 the continued existence of that indivisible 
 thing which I call myself. Whatever this 
 self may be, it is something which thinks, 
 and deliberates, and resolves, and acts, and 
 suffers. I am not thought, I am not action, 
 I am not feeling; I am something that 
 thinks, and acts, and suffers. My thoughts, 
 and actions, and feelings, change every 
 moment — they have no continued, but a 
 successive existence ; but that self or /, to 
 which they belong, is permanent, and has the 
 same relation to all the succeeding thoughts, 
 actions, and feelings, which I call mine. 
 
 Such are the notions that I have of my 
 personal identity. But perhaps it may be 
 said, this may all be fancy without reality. 
 How do you know ? — what evidence have 
 you, that there is such a permanent self 
 which has a claim to all the thoughts, 
 actions, and feelings, which you call yours ? 
 
 To this I answer, that the proper evi- 
 dence I have of all this is remembrance. I 
 remember that, twenty years ago, I conversed 
 with such a person ; I remember several 
 things that passed in that conversation; 
 my memory testifies not only that tliis was 
 done, but that it was done by me who now 
 remember it. If it was done by me, I must 
 have existed at that time, an<l continued to 
 exist from that time to the present : if the 
 identical j)erson whrjni I call myself, had 
 n»t a part in that conversation, my memory 
 is fallacious — it gives a distinct and positive 
 testimony of what is not true. Every man 
 in his senses believes what he distinctly 
 remembers, and everything he remembers 
 r31S-320j 
 
 convinces him that he existed at the time 
 remembered. 
 
 Although memory gives the most irre- 
 sistible evidence of my being the identical 
 person that did such a thing, at such a time, 
 I may have other good evidence of things 
 which befel me, and which I do not remem- 
 ber : I know who bare me and suckled me, 
 but I do not remember these events. [319] 
 It may here be observed, (though the 
 observation would have been unueces^sary if 
 some great philosophers had not contra- 
 dicted it,) that it is not my remembering 
 any action of mine that makes me to be 
 the person who did it. This remembrance 
 makes me to know assuredly that I did it ; 
 but I might have done it though I did not 
 remember it. That relation to me, which 
 is expressed by saying that I did it, would 
 be the same though I had not tlie least re- 
 membrance of it. To say that my remem- 
 bering that I did such a thing, or, as some 
 choose to express it, my being conscious 
 that I did it, makes me to have done it, 
 appears to me as great an absurdity as it 
 would be to say, tiiat my belief that the 
 world was created made it to be created. 
 
 When we pass judgment on the identity 
 of other persons besides ourselves, we pro- 
 ceed upon other grounds, and determine 
 from a variety of circumstances, which 
 sometimes produce the firmest assurance, 
 and sometimes leave room for doubt. The 
 identity of persons has often furnished mat- 
 ter of serious litigation before tribunals of 
 justice. But no man of a sound mind ever 
 doubted of his own identity, as far as he 
 distinctly remembered. 
 
 The identity of a person is a perfect 
 identity ; wherever it is real, it admits of no 
 degrees ; and it is impossible that a person 
 should be in part the same, and in part 
 different ; because a person is a monad, and 
 is not divisilile into parts. The evidence of 
 identity in other persons besides ourselves 
 does indeed admit of all degrees, from what 
 we account certainty to the least degree of 
 probability. But still it is true that the 
 same person is perfectly the same, and can- 
 not be so in part, or in some degree only. 
 
 For this cause, I have first considered 
 personal identity, as that which is perfect 
 in its kind, and tiie natural measure of that 
 which is imperfect. [320] 
 
 We probably at first derive our notion of 
 identity from that natund conviction which 
 every man has frotn the dawn of reason of 
 his own identity and contiiuied existenif. 
 The operations of our minds arc all succes- 
 sive, and have no contiiuied existence. But 
 the thinking being has a continued exist- 
 ence ; and \\e liavean invincilile liclicf tiiat 
 it remains tlie same wlieii all its thouglils 
 and operations change. 
 
 r)ur judgments of the identify of oljccts
 
 d4f) 
 
 ON THE INTELLECTUAL PO\FERS. 
 
 [^ESSAY in. 
 
 of sense seem to be formed much upon tlie 
 same grounds as our judgments of the 
 identity of other persons besides ourselves. 
 
 Wherever we observe great similarity, 
 we are apt to presume identity, if no reason 
 appears to the contrary. Two objects ever 
 so like, when they are perceived at the same 
 time, cannot be the same ; but, if they are 
 presented to our senses at different times, 
 we are apt to think them the same, merely 
 from their similarity. 
 
 Whether this be a natural prejudice, or 
 from whatever cause it proceeds, it cer- 
 tainly appears in children from infancy ; 
 and, when we grow up, it is confirmed in 
 most instances by experience ; for we rarely 
 find two individuals of the same species that 
 are not distinguishable by obvious differ- 
 ences. 
 
 A man challenges a thief whom he finds 
 in possession of his horse or his watch, only 
 on similarity. When the watchmaker 
 swears that he sold this watch to such a 
 person, his testimony is grounded on simi- 
 larity. The testimony of witnesses to the 
 identity of a person is commonly grounded 
 on no other evidence. 
 
 Thus it appears that the evidence we 
 have of our own identity, as far back as we 
 remember, is totally of a different kind from 
 the evidence we have of the identity of other 
 persons, or of objects of sense. The first 
 is grounded on memory, and gives un- 
 doubted certainty. The last is grounded on 
 similarity, and on other circumstances, 
 which in many cases are not so decisive as 
 to leave no room for doubt. [321] 
 
 It may likewise be observed, that the 
 identity of objects of sense is never perfect. 
 All bodies, as they consist of innumerable 
 parts that may be disjoined from them by 
 a great variety of causes, are subject to 
 continual changes of their substance, in- 
 creasing, diminishing, changing insensibly. 
 When such alterations are gradual, because 
 language could not afford a different name 
 for every different state of such a change- 
 able being, it retains the same name, and 
 is considered as the same thing. Thus 
 we say of an old regiment that it did such a 
 thing a century ago, though there now is not 
 a man alive who then belonged to it. We say 
 a tree is the same in the seed-bed and in the 
 forest. A ship of war, which has successively 
 changed her anchors, her tackle, her sails, 
 her masts, her planks, and her timbers, while 
 she keeps the same name, is the same. 
 
 The identity, therefore, which we ascribe 
 to bodies, whether natural or artificial, is 
 not perfect identity ; it is rather some- 
 thing which, for the conveniency of speech, 
 we call identity. It admits of a great 
 change of the subject, providing the change 
 be gradual, sometimes even of a total 
 change. And the changes which in com- 
 
 mon language are made consistent with 
 identity, differ from those that are thought 
 to destroy it, not in kind, but in number 
 and degree. It has no fixed nature wheu 
 applied to bodies ; and questions about the 
 identity of a body are very often questions 
 about words. But identity, when applied 
 to persons, has no ambiguity, and admits 
 not of degrees, or of more and less. It is 
 the foundation of all rights and obligations, 
 and of all accountableness ; and the notion 
 of it is fixed and precise. [322] 
 
 CHAPTER V. 
 
 MR Locke's account of the origin of our 
 
 IDEAS, AND PARTICULARLY OF THE IDEA 
 OF DURATION. 
 
 It was a very laudable attempt of Mr 
 Locke " to inquire into the original of those 
 ideas, notions, or whatever you please to 
 call them, which a man observes, and is 
 conscious to himself he has in his mind, 
 and the ways whereby the understanding 
 comes to be furnished with them.'' No 
 man was better qualified for this investi- 
 gation ; and I believe no man ever en- 
 gaged in it with a more sincere love of 
 truth. 
 
 His success, though great, would, I ap- 
 prehend, have been greater, if he had not 
 too early formed a system or hypothesis 
 upon this subject, without all the caution 
 and patient induction, which is necessary 
 in drawing general conclusions from facts. 
 
 The sum of his doctrine I take to be 
 this — " That all our ideas or notions may 
 be reduced to two classes, the simple and 
 the complex : That the simple are purely 
 the work of Nature, the understanding 
 being merely passive in receiving them : 
 That they are all suggested by two powers 
 of the mind — to wit. Sensation and Reflec- 
 tion ;* and that they are the materials of 
 all our knowledge. That the other class of 
 complex ideas are formed by the under- 
 standing itself, which, being once stored 
 with simple ideas of sensation and reflec- 
 tion, has the power to repeat, to compare, 
 and to combine them, even to an almost 
 infinite variety, and so can make at pleasure 
 new complex ideas : but that is not in the 
 power of the most exalted wit, or enlarged 
 
 * That Locke did not (as even Mr Stewart sup. 
 poses) introduce Reflection, either name or thing, 
 into the philosophy of mind, see Note I. Not 
 was he even the first explicitly to enunciate <Stvw« 
 and Refection as the two sources of our ki.owledge; 
 for I can shew that this had been done in a far more 
 philosophical manner by some of the schoohiien ; 
 Iteflection witli them not being merely, as with 
 Locke, a source of adventitious, empirical, or a pos- 
 teriori knowledge, but the mean by which we di~ 
 close also the native, pure, or a priori cognitiona 
 which the intellect itself contains.— H. 
 
 ^321, 3221
 
 CHAP, v.] LOCKE'S ACCOUNT OF THE IDEA OF DURATION. 347 
 
 understanding, by any quickness or variety 
 of thought, to invent or frame one new 
 simple idea in the mind, not taken in by 
 the two ways before-mentioned. [323] That, 
 as our power over the material world reaches 
 only to the compounding, dividing, and 
 putting together, in various forms, the 
 matter which God has made, but reaches 
 not to the production or annihilation of a 
 single atom ; so we may compound, com- 
 pare, and abstract the original and simple 
 ideas which Nature has given us ; but are 
 unable to fashion in our understanding any 
 simple idea, not received in by our senses 
 from external objects, or by retlection from 
 the operations of our own mind about them." 
 
 This account of the origin of all our ideas 
 is adopted by Bishop Berkeley and Mr 
 Hume; but some very ingenious philoso- 
 phers, who have a high esteem of Locke's 
 Essay, are dissatisfied with it. 
 
 Dr Hutcheson of Glasgow, m his " In- 
 quiry into the Ideas of Beauty and Virtue," 
 lias endeavoured to shew that these are 
 original and simple ideas, furnished by 
 original powers, which he calls the sense of 
 beauty and the moral sense. 
 
 Dr Price, in his " Review of the Principal 
 Questions and Difficulties in Morals," has 
 observed, very justly, that, if we take the 
 words sensation and rrjlectio/i, as Mr Locke 
 has defined them in the beginning of his 
 excellent Essay, it will be impossible to 
 derive some of the most important of our 
 ideas from them ; and that, by the under- 
 standing — that, is by our judging and reason- 
 ing power — we are furnished with many 
 simple and original notions. 
 
 Mr Locke says that, by reflection, he 
 would be understood to mean " the notice 
 which the mind takes of its own operations, 
 and the manner of them." This, I think, we 
 fe commonly call consciousness; from which, 
 indeed, we derive all the notions we have 
 of the operations of our own minds ; and he 
 often speaks of the operations of our own 
 minds, as the only objects of reflection. 
 
 When reflection is taken in this confined 
 sense, to say that all our ideas are ideas 
 » either of sensation or reflection, is to say 
 that everything we can conceive is either 
 some object of sense or some operation of 
 our own minds, which is far from being 
 true. [324] 
 
 But the word reflection is commonly used 
 in a much m<jre extensive sense ; it is ap- 
 plied to many operations of the mind, with 
 more propriety than to that of conscious- 
 ness. We reflect, when we rememlier, or 
 call to mind wiiat is past, and survey it 
 with attention. We reflect, when we define, 
 when we distinguish, when w(f judge, wlicn 
 we reason, wliether about tilings material 
 or intellectual. 
 
 When reflection is taken in tliLn sense, 
 1 .323-325] 
 
 which is more common, and therefore more 
 proper" than the sense which Mr Locke 
 has put upon it, it may be justly said to be 
 the only source of all our distinct and ac- 
 curate notions of things. For, although our 
 first notions of material things are got by 
 the external senses, .and our first notions of 
 the operations of our own minds by con- 
 sciousness, these first notions are neither 
 simple nor clear. Our senses and our con- 
 sciousness are continually shifting from one 
 object to another ; their operations are tran- 
 sient and momentary, and leave no distinct 
 notion of their objects, until they are re- 
 called by memory, examined with attention, 
 and compared with other things. 
 
 This reflection is not one power of the 
 mind ; it comprehends many ; such as re- 
 collection, attention, distinguishing, cora- 
 paring, judging. By these powers our minds 
 are furnished not only with many simple 
 and original notions, but with all our notions, 
 which are accurate and well defined, and 
 which alone are the proper materials of 
 reasoning. Many of these are neither no- 
 tions of the objects of sense, nor of the 
 operations of our own nnnds,.and therefore 
 neither ideas of sensation, nor of reflection, 
 in the sense that Mr Locke gives to reflec- 
 tion. But, if any one chooses to call them 
 ideas of reflection, taking the word in the 
 more common and proper sense, I have no 
 objection. [325] 
 
 Mr Locke seems to me to have used the 
 word reflection sometimes in that limited 
 sense which he has given to it in the defi- 
 nition before mentioned, and sometimes to 
 have fallen unawares into the common sense 
 of the word ; and by this ambiguity his ac- 
 count of the origin of our ideas is dai'kened 
 and perplexed. 
 
 Having premised these things in general 
 of Mr Locke's theory of the origin of our 
 ideas or notions, I proceed to some observ- 
 ations on his account of the idea of dura- 
 tion. 
 
 " Reflection," he says, " upon the train of 
 ideas, which appear one after another in our 
 minds, is that which furnishes us with the 
 idea of succession ; and the distance between 
 any two parts of that succession, is that we 
 call duration." 
 
 If it be meant tliat the idea of succession 
 is prior to that of duration, cither in time 
 or in tlie order of nature, this, I think, is 
 impossible, because succession, as Dr Price 
 justly observes, presujiposes duration, and 
 can in no sense bo prior to it ; and tliero- 
 
 * 'I'his is not correct; and the employment of 
 Reflccti n in anoflier iiieaiiim; than iliat (il inrpoii 
 wfic ('atUTii— tlie retiix kiiowledKe or loineiousiiess 
 which llic iiiiTiil lias of its own Mflections— n whcilly a 
 •eeondatv and li ss iiropei niKinticalioii. .See Ni.te I. 
 I may aRaiii notice, that Iteul vaeilhiles iti Ihiiiiean- 
 in^; he gives to theteini Urlli-i-lum. ('( nipnreahove, 
 p. 'i\ii, note *, and below, \iniler p. !il(i.— II.
 
 348 
 
 ON THE INTELLECTUAL POWERS. 
 
 [esSAV III 
 
 fore it would be more proper to derive the 
 idea of succession from that of duration. 
 
 But how do wc get tlie idea of succession ? 
 It is, says he, by reflecting uponthe train 
 of ideas which appear one after another in 
 our minds. 
 
 Reflecting upon the train of ideas can be 
 nothing but rememberingit, and giving atten- 
 tion to what our memory testifies concern- 
 ing it ; for, if we did not remember it, we 
 could not have a thought about it. So that 
 it is evident that this reflection includes 
 remembrance, without which there could be 
 no reflection on what is past, and conse- 
 quently no idea of succession. [326] 
 
 It may here be observed, that, if we speak 
 strictly and philosophically, no kind of suc- 
 cession can bean object either of the senses 
 or of consciousness ; because the operations 
 of both are confined to the present point of 
 time, and there can be no succession in a 
 point of time ; and on that account the mo- 
 tion of a body, which is a successive change 
 of place, could not be observed by the senses 
 alone without the aid of memory. 
 
 As this observation seemS' to contradict 
 the common sense and common language of 
 mankind, when they aflSrm that they see a 
 body move, and hold motion to be an. object 
 of the senses, it is proper to take notice, that 
 this contradiction between the philosopher 
 and the vulgar is apparent only, and not 
 real. It arises from this, that philosophers 
 and the vulgar differ in the meaning they 
 put upon what is called the present time, 
 and are thereby led to make a diff"erent limit 
 between sense and memory. 
 
 Philosophers give the name of the pre- 
 sent to that indivisible point of time, which 
 divides the future from the past : but the 
 vulgar find it more convenient in the affairs 
 of life, to give the name of present to a por- 
 tion of time, which extends more or less, 
 according to circumstances, into the past or 
 the future. Hence we say, the present 
 hour, the present year, the present century, 
 tliough one point only of these periods can 
 be present in the philosophical sense. 
 
 It has been observed by grammarians, 
 that the present tense in verbs is not con- 
 fined to an indivisible point of time, but is 
 80 far extended as to have a beginning, a 
 middle, and an end ; and that, in the most 
 copious and accurate languages, these dif- 
 ferent parts of the present are distinguished 
 by different forms of the verb. 
 
 As the purposes of conversation make it 
 convenient to extend what is called the pre- 
 sent, the same reason leads men to extend 
 the province of sense, and to carry its limit 
 as far back as they carry the present. Thus 
 a man may say, I saw such a person just 
 now : it would be ridiculous to find fault 
 with this way of speaking, because it is 
 authorized by custom, and has a distinct 
 
 meaning. [327] But, if we speak philoso- 
 phically, the senses do not testify what we 
 saw, but only what we see ; what I saw 
 last moment I consider as the testimony of 
 sense, though it is now only the testimony 
 of memory. 
 
 There is no necessity in common life of 
 dividing accurately the provinces of sense 
 and of memory ; and, therefore ,we assign to 
 sense, not an indivisible point of time, but 
 that small portion of time which we call the 
 present, which has a beginnuig, a middle, 
 and an end. 
 
 Hence, it is easy to see that, though, in 
 common language, we speak with perfect 
 propriety and truth, when we say that we 
 see a body move, and that motion is an ob- 
 ject of sense, yet when, as philosophers, we 
 distinguish accurately the province of sense 
 from that of memory, we can no more see 
 what is past, though but a moment ago, 
 tlian we can remember what is present ; so 
 that, speaking philosophically, it is only by 
 the aid of memory that we discern motion, 
 or any succession whatsoever. We see the 
 present place of the body ; we remember 
 the successive advance it made to that 
 place : the first can then only give us a 
 conception of motion when joined to the last. 
 
 Having considered the account given by 
 Mr Locke, of the idea of succession, we 
 shall next consider how, from the idea of 
 succession, he derives the idea of duration. 
 
 " The distance," he says, " between any 
 parts of that succession, or between. the 
 appearance of any two ideas in our minds, 
 is that we call duration." 
 
 To conceive this the more distinctly, let 
 us call the distance between an idea and 
 that which immediately succeeds it, one ele- 
 ment of duration ; the distance between an 
 idea, and the second that succeeds it, two 
 elements, and so on : if ten such elements 
 make duration, then one must make dura- 
 tion, otherwise duration must be made up of 
 parts that have no duration, which is im- 
 possible. [328] 
 
 For, suppose a succession of as many 
 ideas as you please, if none of these ideas 
 have duration, nor any interval of duration 
 be between one and another, then it is 
 perfectly evident there can be no interval 
 of duration between the first and the last, 
 how great soever their number be. I con- 
 clude, therefore, that there must be dura- 
 tion in every single interval or element of 
 which the whole duration is made up. 
 Nothing indeed, is more certain, than that 
 every elementary part of duration must 
 have duration, as every elementary part of 
 extension must have extension. 
 
 Now, it must be observed that, in these 
 elements of duration, or single intervals of 
 successive ideas, there is no succession of 
 ideas ; yet we must conceive them to have 
 
 [326 -328 j
 
 cuAP. v.] LOCKE'S ACCOUNT OF THE IDEA OF DURATION. 349 
 
 duration ; whence we may conclude with 
 certainty, that there is a conception of du- 
 ration, where there is no succession of ideas 
 in the mind. 
 
 We may measure duration by the suc- 
 cession of thoughts in the mind, as we mea- 
 sure length by inches or feet ; but the notion 
 or idea of duration must be antecedent to 
 the mensuration of it, as the notion of 
 length is antecedent to its being measured. 
 
 Mr Locke draws some conclusions from 
 his account of the idea of duration, which 
 may serve as a touchstone to discover how 
 far it is genuine. One is, that, if it were 
 possible for a waking man to keep only one 
 idea in his mind without variation, or the 
 succession of others, he would have no per- 
 ception of duration at all ; and the moment 
 lie began to have this idea, would seem to 
 have no distance from the moment he 
 ceased to have it. 
 
 Now, that one idea should seem to have 
 no dui'ation, and that amultiplication of that 
 no duration should seem to have duration, 
 appears to me as impossible as that the 
 multiplication of nothing should produce 
 something. [329] 
 
 Another conclusion whicli the author 
 draws from this theory is, that the same 
 period of duration appears long to us when 
 the succession of ideas in our mind is quick, 
 and short when the succession is slow. 
 
 There can be no doubt but the same 
 length of duration appears in some circum- 
 stances much longer than in others ; the 
 time appears long; when a man is impatient 
 under any pain or distress, or when he is 
 eager in the expectation of some happiness. 
 On the other hand, when he is pleased and 
 happy in agreeable conversation, or delighted 
 witli a variety of agreeable objects that 
 strike his senses or his imagination, time 
 flies away, and appears short. 
 
 According to Mr Locke's theory, in the 
 first of these cases, the succession of ideas 
 is very quick, and in the last very slow. I 
 am rather inclined to think that the very 
 contrary is the truth. When a man is racked 
 with pain, or with expectation, he can 
 hardly think of anything but his distress ; 
 and the more his mind is occupied by that 
 sole oljject, the longer the time appears. 
 On the other hand, when he is entertained 
 with cheerful music, with lively conversa- 
 tion, and brisk sallies of wit, there seems 
 to be the quickest succession of ideas, but 
 the time apjiears shortest. 
 
 I have heard a military officer, a man of 
 candour and observation, say, that the time 
 he was engiiged in hot action always. a]i- 
 peared to liim mtjch shorler than it really 
 was. Yet I think it cannot be supposed 
 that the succesHion of ideas was then slower 
 than usual.' 
 
 * In tiavelling, the limp^cemK very iihorl. while 
 [329, 330 ] 
 
 If the idea of duration were got merely 
 by the succession of ideas in our minds, 
 that succession must, to ourselves, appear 
 equally quick at all times, because the only 
 measm-e of duration is the number of suc- 
 ceeding ideas ; but I believe every man 
 capable of reflection will be sensible, that 
 at one time his thoughts come slowly and 
 heavily, and at another time have a much 
 quicker and livelier motion. [330] 
 
 I know of no ideas or notions that have 
 a better claim to be accounted simple and 
 original than those of Space and Time. It 
 is essential both to space and time to be 
 made up of parts ; but every part is similar 
 to the whole, and of the same nature. Dif- 
 ferent parts of space, as it has three dimen- 
 sions, may differ both in figure and in mag- 
 nitude ; but time having only one dimen- 
 sion, its parts can difier only in magnitude ; 
 and, as it is one of the simplest objects of 
 thought, the conception of it must be purely 
 the effect of our constitution, and given us 
 by some original power of the mind. 
 
 The sense of seeing, by itself, gives us 
 the conception and belief of only two dimen- 
 sions of extension, but the sense of touch 
 discovers three ; and reason, from the con- 
 templation of finite extendi d things, leads 
 us necessarily to the belief of an immensity 
 that contains them.* In like manner, me- 
 mory gives us the conception and belief of 
 finite intervals of duration. From the con- 
 templation of these, reason leads us neces- 
 sarily to the belief of an eternity, which 
 comprehends all things that have a begin- 
 ning and end.* Our conceptions, both of 
 space and time, are probably partial and 
 inadequate, ■}• and, therefore, we are apt to 
 lose ourselves, and to be embarrassed in 
 our reasonings about them. 
 
 Our understanding is no less puzzled 
 wlien we consider the minutest parts of 
 time and space than when we consider the 
 whole. We are forced to acknowledge 
 that in their nature they are divisilile with- 
 out end or limit ; but there are limits be- 
 yond which our faculties can divide neither 
 the one nor the other. 
 
 It may be determined by experiment, 
 what is the least angle under which an 
 object may be discerned by the eye, and 
 wliat is the least interval of duration that 
 may be discerned by the ear. I believe 
 these may be difl'erent in different persons : 
 But surely there is a limit which no 
 man can exceed: and wliat our faculties 
 can no longer divide is still divisible in it- 
 
 p.is^iiiK ; viry long iii rctrojpect. 'J ho caune is ob 
 VloU^. — 1 1. 
 
 * See above, \>. 3ir!, note *.— H. 
 
 t Tlicy arc not I'tolinlily but neresiarily pnttlal 
 and in;i(lo(junU'. I'or we are urmlile ixisilivily n 
 conceive I nne or Space, eillur an Infinite, (i. <•.. 
 without liiiiila,) or a; not inlinitc (i. <■., an liniiieU.) 
 — II.
 
 350 
 
 ON THE INTELF.ECTUAL POWERS. 
 
 [essay III. 
 
 self, and, by beings of superior perfection, 
 may be divided into thousands of parts. 
 [3311 
 
 I have reason to believe, that a good eye 
 in the prime of life may see an object under 
 an angle not exceeding half a minute of a 
 degree, and I believe there are some human 
 eyes still more perfect. But even this de- 
 gree of perfection will appear great, if we 
 consider how small a part of the retina of 
 the eye it must be which subtends an angle 
 of half a minute. 
 
 Supposing the distance between the centre 
 of the eye and the retina to be six or seven 
 tenths of an inch, the subtense of an angle 
 of half a minute to that radius, or the 
 breadth of the image of an object seen under 
 that angle, will not be above the ten thou- 
 sandth part of an inch. This shews sucli 
 a wonderful degree of accuracy in the re- 
 fracting power of a good eye, that a pencil 
 of rays coming from one point of the object 
 shall meet in one point of the retina, so as 
 not to deviate from that point the ten 
 thousandth part of an inch. It shews, 
 likewise, that such a motion of an object as 
 makes its image on the retina to move the 
 ten thousandth part of.an inch, is discern- 
 ible by the mind. 
 
 In order to judge to what degree of ac- 
 curacy we can measure short intervals of 
 time, it may be observed that one who has 
 given attention to the motion of a Second 
 pendulum, will be able to beat seconds for 
 a minute with a very small error. When 
 he continues this exercise long, as for five 
 or ten minutes, he is apt to err, more even 
 than in proportion to the time— for this 
 reason, as I apprehend, that it is difficult to 
 attend long to the moments as they pass, 
 without wandering after some other object 
 of thought. 
 
 I have found, by some experiments, that 
 a man may beat seconds for one minute, 
 without erring above one second in the 
 whole sixty ; and I doubt not but by long 
 practice he might do it still more accurately. 
 From this I think it follows, that the six- 
 tieth part of a second of time is discernible 
 bv the human mind. [332] 
 
 CHAPTER VI. 
 
 OF MR LOCKE*S ACCOUNT OF OUR PERSONAL 
 IDENTITY. 
 
 In a long chapter upon Identity and 
 Diversity, Mr Locke has made many in- 
 genious and just observations, and some 
 which I think cannot be defended. I shall 
 only take notice of the account he gives of 
 our own Personal Identity. His doctrine 
 upon this subject has been censured by 
 Bishop Butler, in a short essay subjoined to 
 
 his " Analogy," with whose sentiments I 
 perfectly agree. 
 
 Identity, as was observed. Chap. IV. of 
 
 this Essay, supposes the continued existence 
 of the being of which it is affirmed, and 
 therefore can be applied only to things which 
 have a continued existence. Wliile any 
 being continues to exist, it is the same being : 
 but two beings which have a different be- 
 ginning or a different ending of their exist- 
 ence, cannot possibly be the same. To this 
 I think Mr Locke agrees. 
 
 He observes, very justly, that to know 
 what is meant by the same person, we must 
 consider what the word peison stands for ; 
 and he defines a person to be an intelligent 
 being, endowed with reason and with con- 
 sciousness, which last he thinks inseparable 
 from thought. 
 
 From this definition of a person, it must 
 necessarily follow, that, while the intelligent 
 being continues to exist and to be intelli- 
 gent, it must be the same person. To say 
 that the intelligent being is the person, and 
 yet that the person ceases to exist, while 
 the intelligent being continues, or that the 
 person continues while the intelligent being 
 ceases to exist, is to my apprehension a 
 manifest contradiction. [333 J 
 
 One would think that the definition of a 
 person should perfectly ascertain the nature 
 of personal identity, or wherein it consists, 
 though it might still be a question how we 
 come to know and be assured of our per- 
 sonal identity. 
 
 Mr Locke tells us, however, " that per- 
 sonal identity — that is, the sameness of a 
 rational being — consists in consciousness 
 alone, and, as far as this consciousness can 
 be extended backwards to any past action 
 or thought, so far reaches the identity of 
 that person. So that, whatever hath the 
 consciousness of present and past actions, 
 is the same person to whom they belong."* 
 
 * See Essay, (Book ii. cb. 27, ?. 9.) The passage 
 given as a quotation in the .text, is the sum of 
 Locke's doctrine, but not exactly in his words. Long 
 before Butler, to whom the merit is usually ascribed, 
 Li cke's doctrine of Personal Identity had been 
 attai keo and refuted. This was done even by his 
 earliest critic, John Sergeant, whose words, as he 
 is.an author wholly unknown to all historians of phi. 
 losophy, and his works of the rarest, I shall quote. 
 He thus argues : — ■' The former distinction forelaid, 
 he ( Locke) proceeds to makepersonal identUy in man 
 to Consist in the consciousness that we are the same 
 thinkinfl thinfj in differeyit times and^places. He 
 proves it, because consciousness is inseparable from 
 thinking, and, as it seems to him, essential to it. 
 Perhaps he may have had second thoughts, since he 
 writ his 19th Chapter, where, ^ 4, he thought it 
 jirobable that Thinking is but the action, and not the 
 essence of the soul. His reason here is — ' Because 
 'tis impossible for any to perceive, without perceiving 
 that he does perceive,' which I have shewn above to 
 be so far from impossible, that the contrary is such. 
 B'Jt, to speak to the point : Consciousness of any 
 action or other accident we have now, or have had, 
 is nothing but our knowledj;e that it belonged to us ; 
 and, since we both -agree that we have no .innate 
 knowledges, it follows, that all, both actual and habi. 
 i lual knowledges, which we have, are acquired orac- 
 
 [331 3.331
 
 CHAP. VI.] LOCKE'S ACCOUNT OF OUR. PERSONAL IDENTITY. 351 
 
 This doctrine hath some strange conse- 
 quences, which the author was aware of, 
 Such as, that, if the same consciousness can 
 be transferred from one intelligent being to 
 another, which he tliinks we cannot shew 
 to be impossible, then two or twenty intel- 
 ligent beings may be the same person. And 
 if the intelligent being may lose the con- 
 sciousness of the actions done by him, which 
 surely is possible, then he is not the person 
 that did those actions ; so that one intelli- 
 gent being may be two or twenty different 
 persons, if he shall so often lose the con- 
 sciousness of his former' actions. 
 
 There is another consequence of this 
 doctrine, which follows no less necessarily, 
 though Mr Locke probably did not see it. 
 It is, that a man may be, and at the same 
 time not be, the person that did a particular 
 action. 
 
 Suppose a brave officer to have been 
 flogged when a boy at school, for robbing 
 an orchard, to have taken a standard from 
 the enemy in his first campaign, and to have 
 been made a general in advanced life : Sup- 
 pose also, which must be admitted to be 
 possible, that, when he took the standard, 
 
 cidental to the subject or knower. Wherefores the 
 man, or that thi»ij which: is to be the knoirer, must 
 have had indtviduality or pcrsonaliti/, from other 
 principles, antecedaitly to this knoivledpc, called 
 consciousness : and, consequently, he ivill retain his 
 identity, or continue the sayne man, or (which- is 
 equivalent) the same person, as lonp as he has those 
 itidividuatintj principles, \\'hat tliose principles are 
 which constitute this mari; or this knowing -indici- 
 duum, I have shewn above, ^ ^ 6, 7. It being then 
 most evident, t}tat a man must he the same, ere he can 
 knoie or be conscious that he is the same, all his 
 laborious dcscsnts and extravagant consequences 
 which are built upon this supposition, that conscious- 
 ness individuates the person, can need no farther 
 refutation." 
 
 '1 he fame objection was also made by Leibnitz in 
 his strictures on Locke's Essay. Inter alia, he says — 
 " Pour ce qui est du soi i! sera ben de le (iislinguer 
 de I'appiirence du soi et de laconsciosite Le soi fait 
 ridentit^ rcelle ct physique, et lajiparcnce du soi, 
 accompagnee de la verite, yjnint I'identitepersonelle. 
 Ainsi ne voulant point dire, que Tidentite personellc 
 nes'etei d pas plus loin que le si puvenirjedirois encore 
 Dioins que le soi ou I'identite i hysque en depend. 
 L'identite reelect personeilescprouvelepluscertain- 
 inenl qu'il se.peut en matiOrc de (ait, par la reflexion 
 presenteet immediate; die sepronve.vuffisament pour 
 i'ordinairc par notre souvenir d'lntcrvalle ou par le 
 temeignage cotispirant des autres. Mais si Dicu 
 changeoit extraordinairment I'idontite reele, lapcr- 
 sonelle demeuroit, pourvu qne I'homme conservat 
 les apparenccs d'idenlite, tant les internes, {c'esfti 
 dire de la conscience,) que lesextcrnes, commecclles 
 qui consistent dans ce qui paroit aux autres. Ainsi 
 la conscience n'est pas le seul moyen'ile constitucr 
 l'identite pii«onclle, et le rapport d'autrui ou mime 
 d'autresmarqClesy peuvent supplier. Mais ilyadcla 
 difficult(-, s'il BC trnuvc contradiclion entrecesdivei. 
 «e« apparc' cc'v. La conscience m- peut tairc coinme 
 dans i'oubll ; maissi elle disoit hiin clairment des 
 rhoscs, qui tuspent contraircsaiix autres apparcnres, 
 on seroit emharasst dans la decision et conime sus. 
 pendO qiielqucs fois entre deux uossibilites, cellede 
 I'trrcur du noire souvenir ( t relic de quelque decep. 
 tion dans les apparcnces extcrnef." 
 
 For the Ik'H criticism of Ix)ck<''s doctrine of I'ersn. 
 nal Identity, I may, however, reler the reader to IM. 
 Cousin's "Court de Fhiloiophic," t. ii., Lei;on xviii., 
 p. I!<0-H(H.— H. 
 
 [.S31-, 3;}.5] 
 
 he was conscious of his having been flogged 
 at school, and that when'made a general he 
 was conscious of his taking the standard, 
 but had absolutely lost the consciousness of 
 his flogging. [334] 
 
 These things being supposed, it follows, 
 from Mr Locke's doctrine, that he who was 
 flogged at school is the same jierson who 
 took the standard, and that he whotoi-kthe 
 standard is the same person who was made 
 a general. Whence it follows, if there be 
 any truth in logic, that the general is the 
 same person with him who was flogged 
 at school. But the general's consciousness 
 does not reach so far back as his flogging — 
 therefore, according to Mr Locke's doctrine, 
 he is not the person who was flogged. 
 Therefore, the general is, and at the same 
 time is not the same person with him who 
 was flogged at school.* 
 
 Leaving the consequences of this doctrine 
 to those who have leisure to trace them, we 
 may observe, with regard to the doctrine 
 itself— 
 
 First, That Mr Locke attributes to con- 
 sciousness the conviction we have of our 
 past actions, as if a man may now be con- 
 scious of what he did twenty years ago. 
 It is impossible to understand the meaning 
 of this, unless by consciousness be meant 
 memory, theonly faculty by which wehavean 
 immediate knowledge of our past actions.-f- 
 
 Sometimes, in popular discourse, a man 
 says he is conscious that he did such a 
 thing, meaning that he distinctly remembers 
 that he did it. It is unnecessary, in com- 
 mon discourse, to fix accurately the limits 
 between consciousness and memory. This 
 was formerly shewn to be the case with re- 
 gard to sense and memory : and, therefore, 
 distinct remembrance is sometimes called 
 sense, sometimes consciousness, without 
 any inconvenience. 
 
 But this ought to be avoided in philoso- 
 phy, otherwise we confound the difleront 
 l)owers of the mind, and ascribe to one what 
 really belongs to another. If a man can be 
 conscious of what he did twenty years or 
 twenty minutes ago, there is no use for 
 memory, nor ought we to allow tliat there 
 is any such faculty. [335] The faculties of 
 consciousness and memory are chiefly dis- 
 tinguished by this, that the first is an im- 
 mediate knowledge of tliejirosent, the second 
 an immediate knowledge of the past. J 
 
 Wlicn, therefore, Mr Locke's notion of 
 
 * Compare Huffier's " Traitddes prt'micres Vi'rilez," 
 ( Ihinnrques sur Locke, J 5(6,; who niakesw similar 
 criticism. — H. 
 
 t Locke, ii.will he remembered, does not, like 
 Iteid, view con.-ciousiicss ns aco-ordinate faculty with 
 memory; but under coiifciousniss he proprrlv com- 
 prehends the various Incullies as so •many «\ieci;J 
 modifications, — M. 
 
 f As already Iriquently stated, an imvicdiott 
 knowledge ol the yictMskcontradirtory. I Iih ob. 
 servatioii I cannot again repeat. See Note I). — II.
 
 352 
 
 ON THE INTELLECTUAL POWERS. 
 
 [essay hi. 
 
 personal identity is properly expressed, it is 
 that personal identity consists in distinct 
 remembrance ; for, even in the popular 
 sense, to say that I am conscious of a past 
 action, means nothing else than that I dis- 
 tinctly remember that I did it. 
 
 Secondli/, It may be observed, that, in 
 this doctrine, not only is consciousness con- 
 founded with memory, but, which is still 
 more strange, personal identity is confounded 
 with the evidence which we have of our 
 personal identity. 
 
 It is very true that my remembrance 
 that I did such a thing is the evidence I 
 have that I am the identical person who did 
 it. And this, I am apt to think, Mr Locke 
 meant. But, to say that my remembrance 
 that I did such a thing, or my conscious- 
 ness, makes me the person who did it, is, in 
 my apprehension, an absurdity too gross to 
 be entertained by any man who attends to 
 the meaning of it ; for it is to attribute to 
 memory or consciousness, a strange magi- 
 cal power of producing its object, though 
 that object must have existed before the 
 memory or consciousness which produced it. 
 
 Consciousness is the testimony of one 
 faculty ; memory is the testimony of another 
 faculty. And, to say that the testimony is 
 the cause of the thing testified, this surely 
 is absurd, if anything be, and could not 
 have been said by Mr Locke, if he had not 
 confounded the testimony with the thing 
 testified. 
 
 When a horse that was stolen is found 
 and claimed by the owner, the only evidence 
 he can have, or that a judge or witnesses 
 can have that this is the very identical horse 
 which was his property, is similitude, [336] 
 But would it not be ridiculous from this to 
 infer that the identity of a horse consists in 
 similitude only ? The only evidence I have 
 that I am the identical person who did such 
 actions is, that I remember distinctly I did 
 them ; or, as Mr Locke expresses it, I am 
 conscious I did them. To infer from this, 
 that personal identity consists in conscious- 
 ness, is an argument which, if it had any 
 force, would prove the identity of a stolen 
 horse to consist solely in similitude. 
 
 Thinlhj, Is it not strange that the same- 
 ness or identity of a person should consist 
 in a thing which is continually changing, 
 and is not any two minutes the same ? 
 
 Our consciousness, our memory, and 
 every operation of the mind, are still flow- 
 ing, like the water of a river, or like time 
 itself. The consciousness I have this 
 moment can no more be the same conscious- 
 ness I had last moment, than this moment 
 can be the last moment. Identity can only 
 be affirmed of things which have a continued 
 existence. Consciousness, and every kind 
 of thought, is transient and momentary, and 
 iias no continued existence ; and, there- 
 
 fore, if personal identity consisted in con- 
 sciousness, it would certainly follow that no 
 man is the tame person any two moments 
 of his life ; and, as the right and justice of 
 reward and punishment is founded on per- 
 sonal identity, no man could be responsible 
 for his actions. 
 
 But, though I take this to be the una- 
 voidable consequence of Mr Locke's doc- 
 trine concerning personal identity, and 
 though some persons may have liked the 
 doctrine the better on this account, I am 
 far from imputing anything of this kind to 
 Mr Locke. He was too good a man not to 
 have rejected with abhorrence a doctrine 
 which he believed to draw this consequence 
 after it. [337] 
 
 Fourthly, There are many expressions 
 used by Mr Locke, in speaking of personal 
 identity, which, to me, are altogether unin- 
 telligible, unless we suppose that he con- 
 founded that sameness or identity which we 
 ascribe to an individual, with the identity 
 which, in common discourse, is often ascribed 
 to many individuals of the same species. 
 
 When we say that pain and pleasure, 
 consciousness and memory, are the same in 
 all men, this sameness can only mean simi- 
 larity, or sameness of kind ; but, that the 
 pain of one man can be the same individual 
 pain with that of another man, is no les3 
 impossible than that one man should be 
 another man ; the pain felt by me yester- 
 day can no more be the pain I feel to-day, 
 than yesterday can be this day; and the 
 same thing may be said of every passion 
 and of every operation of the mind. The 
 same kind or species of operation may be 
 in diff'erent men, or in the same man at 
 different times ; but it is impossible that the 
 same individual operation-should be in dif- 
 ferent men, or in the same mam at different 
 times. 
 
 When Mr Locke, therefore, speaks of " the 
 same consciousness being continued through 
 a succession of different substances ;" when 
 he speaks of " repeating the idea of a past 
 action, witli the same consciousness we had 
 of it at the first," and of " the same con- 
 sciousness extending to actions past and to 
 come" — these expressions are to me unin- 
 telligible, unless he means not the same in- 
 dividual consciousness, but a consciousness 
 that is similar, or of the same kind. 
 
 If our personal identity consists in con- 
 sciousness, as this consciousness cannot be 
 the same individually any two moments, 
 but only of the same kind, it would follow 
 that we are *,not for any two moments the 
 same individual persons, but the same kind 
 of persons. 
 
 As our consciousness sometimes ceases 
 to exist, as in sound sleep, our personal 
 identity must cease with it. Mr Locke 
 allows, that the same thing cannot have 
 
 [336, 337]
 
 CHAP. VII ] 
 
 THEORIES CONCERNING MEMORY. 
 
 353 
 
 two begiunin<;s of existence ; so that our 
 identity would be irrecoverably gone every 
 time we cease to think, if it was but lor a 
 a moment.* [338] 
 
 CHAPTER VII. 
 
 THEORIES CONCERNING MEMORY. 
 
 The common tlieory of ideas — that is, 
 of images in the brain or in the mind, of 
 all the objects of thought— has been very 
 generally applied to account for the facul- 
 ties of memory and imagination, as well as 
 that of perception by the senses. 
 
 The sentiments of the Peripatetics are 
 expressed by Alexander Aphrodisiensis, 
 one of the earliest Greek commentators on 
 Aristotle, in these words, as they are trans- 
 lated by Mr Harris in his " Hermes :" — 
 " Now, what Phancy or Imagination is, we 
 may explain as follows : — We may conceive 
 to be formed within us, from the operations of 
 our senses about sensible objects, some Im- 
 pression, as it were, or Picture, in our origi- 
 nal Seusorium, being a relict of that motion 
 caused within us by the external object ; a 
 relict which, when the external object is 
 no longer present, remains, and is still 
 preserved, being, as it were, its Image, 
 
 * It is here proper to insert Reid's remarks on 
 Personal Identity, as published by Lord Karnes, in 
 his " Essays on the Principlesof Morality and Natural 
 Religion," (third edition, p. 2(4.) 'Jhcse, perhaps, 
 might have more appropriately lound their place in 
 the ("orrespondeiice ot our Author. 
 
 " To return to our subject," says his Lordship, 
 " Mr Locke, writing on personal identity, has fallen 
 short of his usual accuracy. Heinadvertentlyjumbles 
 together the irieniily that is na'ure's work, with 
 our knowledtieol it. Nay, hecxpres^es himsell some, 
 times as if identity had no other foundation than 
 that knowled(;e. I am favoured by IJr Kcid with the 
 following thoughts on personal identity : — 
 
 '" All men agiee that personality i< indivisiblo ; a 
 part of a peisoii IS an absurdity. A man who loses 
 his estate, his health, an arm, or a leg, continues sti 1 
 to bethe same person. My personal identity, then fore, 
 is the continued existence of that indivisible thing 
 which 1 call myself. 1 am not ilnughl ; 1 am not 
 action ; I ?m not feeling; but I think, and act, and 
 feel. Thoughts, actions, feeling's, change every 
 moment; but ,«■</■, to which i hey belong, is perman. 
 ent. If it be asked bow I know that it is permanent, 
 the answer is, that I know it from memory. Every, 
 thing I remember to have seen, or hc.ird, or done, or 
 suftereii, convinces me that I existed at the time 
 reinemberid. Hut, though it is from iiHinor> that I 
 have the knowledge ot my pergonal identity, yet jier- 
 KOnal identity must exist in nature, iiwiepnident of 
 memory ; otherwise, I should only be the same per. 
 unn as far as my memory servos me , and what would 
 beco I e of my existence during the intervals wherein 
 my tneiiiory has failed me ? My rememberaiiieot any 
 I t my nc'.ion» does noi make me to be the person wlio 
 did the action, but only makes inc know that I was 
 the per^on who did it. And yet it wss Mr I/icke's 
 opiiiion, that my remembranc of an action is what 
 makes mi to be the person wliodid it; a pregnant 
 insta' ce that even mm of the greatest genius may 
 ioineiiinea 'all into an atisunlity. Is it not an obvious 
 corollary, Irom Mr Locke's opinion, fliat he never 
 was Ixitii ? He could not remeinbir his birth ; and, 
 thcrclore, was not the pereon born at such a place 
 and at such a time.'"— H. 
 
 and which, by being thus preserved, be- 
 comes the cause of our having Memory. 
 Now, such a sort of relict, and, as it were, 
 impression, they call Phancy or Imagina- 
 tion."* 
 
 Another passage from Alcinous Of the 
 Doctrines of Plato, chap. 4, shews the agree- 
 ment of the ancient Platonists and Peripa- 
 tetics in this theory : — " When the form or 
 type of things is imprinted on the mind by 
 the organs of the senses, and so imprinted 
 as not to be deleted by time, but preserved 
 firm and lasting, its preservation is called 
 Memory."* [339] 
 
 Upon this principle, Aristotle imputes the 
 shortness of memory in children to this 
 cause — that their brain is too moist and soft 
 to retain impressions made upon it : and 
 the defect of memory in old men he imputes, 
 on the contrary, to the hardness and rigidity 
 of the brain, which hinders its receiving 
 any durable impression. -f- 
 
 This ancient theory of the cause of 
 memory is defective in two respects : First, 
 If the cause assigned did really exist, it by 
 no means accounts for the phoenomenon ; 
 and, secondly. There is no evidence, nor 
 even probability, that that cause exists. 
 
 It is probable that in perception some 
 impression is made upon the brain as well 
 as upon the organ and nerves, because all 
 the nerves terminate in the brain, and be- 
 cause disorders and hurts of the brain are 
 found to affect our powers of perception 
 when the external organ and nerve are 
 found ; but we are totally ignorant of the 
 nature of this impression upon the brain : 
 it can have no resemblance to the object 
 perceived, nor does it in any degree ac- 
 count for that sensation and perception 
 which are consequent upon it. These things 
 have been argued in the second Essay, and 
 shall now be taken for granted, to prevent 
 repetition. 
 
 If the impression upon the brain be insuf- 
 ficient to account for the perception of ob- 
 jects that are present, it can as little account 
 for the memory of those that are past. 
 
 So that, if it were certain that the im- 
 pressions made on the brain in perception 
 remain as long as there is any memory of 
 the object, all that could be inferred from 
 this, is, that, by the laws of Natin-e, there 
 is a connection established between that im- 
 pression, and the retnemberance of that 
 object. But how the impression contributes 
 
 * The inference founded on these passages, i««lto. 
 gelher erroneous. See Note K. — H. 
 
 t In ihis whole statement Held i« wrong. In the 
 
 [338,3391
 
 354 
 
 ON THE INTELLECTUAL POWERS. 
 
 [essav in. 
 
 to this remembrance, we should be quite 
 ignorant ; it being impossible to discover 
 how thought of any kind should be pro- 
 duced, by an impression on the brain, or 
 upon any part of the body. [340] 
 
 To say that this impression is memory, ia 
 absurd, if understood literally. If it is only 
 meant that it is the cause of memory, it 
 ought to be shewn how it produces this 
 effect, otherwise memory remains as unac- 
 countable as before. 
 
 If a philosopher should undertake to ac- 
 count for the force of gunpowder in the 
 discharge of a musket, and then tell us 
 gravely that the cause of this phsenomenon 
 is the drawing of the trigger, we should not 
 be much wiser by this account. As little 
 are we instructed in the cause of memory, 
 by being told that it is caused by a certain 
 impression on the brain. For, supposing 
 that impression on the brain were as neces- 
 sary to memory as the drawing of the trigger 
 is to the discharge of the musket, we are 
 still as ignorant as we were how memory is 
 produced ; so that, if the cause of memory, 
 assigned by this theory, did really exist, it 
 does not in any degree account for memory. 
 
 Another defect in this theory is, that 
 there is no evidence nor probability that 
 the cause assigned does exist ; that is, that 
 the impression made upon the brain in per- 
 ception remains after the object is removed. 
 
 That impression, whatever be its nature, 
 is caused by the impression made by the 
 object upon the organ of sense, and upon 
 the nerve. Philosophers suppose, without 
 any evidence, that, when the object is re- 
 moved, and the impression upon the organ 
 and nerve ceases, the impression upon the 
 brain continues, and is permanent ; that is, 
 that, when the cause is removed, the effect 
 continues. The brain surely does not ap- 
 pear more fitted to retain an impression 
 than the organ and nerve. 
 
 But, granting that the impression upon 
 the brain continues after its cause is re- 
 moved, its effects ought to continue while 
 it continues ; that is, the sensation and 
 perception should be as permanent as the 
 impression upon the brain, which is sup- 
 posed to be their cause. But here again 
 the philosopher makes a second supposition, 
 with as little evidence, but of a contrary 
 nature — to wit, that, while the cause re- 
 mains, the effect ceases. [34 1 ] 
 
 If this should be granted also, a third 
 must be made — That the same cause which 
 at first produced sensation and perception, 
 does afterwards produce memory — an opera- 
 tion essentially different, both from sensa- 
 tion and perception. 
 
 A fourth supposition must be made — 
 That this cause, though it be permanent, 
 does not produce its effect at all times ; it 
 must be like an inscription which is some- 
 
 times covered with rubbish, and on other 
 occasions made legible ; for the memory of 
 things is often interrupted for a long time, 
 and circumstances bring to our recollection 
 what had been long forgot. After all, many 
 things are remembered which were never 
 perceived by the senses, being no objects of 
 sense, and therefore which could make no 
 impression upon the brain by means of the 
 senses. 
 
 Thus, when philosophers have piled one 
 supposition upon another, as the giants piled 
 the mountains in order to scale the heavens, 
 all is to no purpose — memory remains unac- 
 countable ; and we know as little how we 
 remember things past, as how we are con- 
 scious of the present. 
 
 But here it is proper to observe, that, 
 although impressions upon the brain give 
 no aid in accounting for memory, yet it is 
 very probable that, in the human frame, 
 memory is dependent on some proper state 
 or temperament of the brain.* 
 
 Although the furniture of our memory 
 bears no resemblance to any temperament 
 of brain whatsoever, as indeed it is impos- 
 sible it should, yet nature may have sub- 
 jected us to this law, that a certain consti- 
 tution or state of the brain is necessary to 
 memory. That this is really the case, 
 many well-known facts lead us to con- 
 clude. [342] 
 
 It is possible that, by accurate observa- 
 tion, the proper means may be discovered 
 of preserving that temperament of the brain 
 which is favourable to memory, and of 
 remedying the disorders of that tempera- 
 ment. This would be a very noble im- 
 provement of the medical art. But, if it 
 should ever be attained, it would give no 
 aid to understand how one state of the brain 
 assists memory, and another hurts it. 
 
 I know certainly, that the impression 
 made upon my hand by the prick of a pin 
 occasions acute pain. But can any philo- 
 sopher shew how this cause produces the 
 effect ? The nature of the impression is 
 here perfectly known ; but it gives no help 
 to understand how that impression affects 
 the mind ; and, if we knew as distinctly that 
 state of the brain which causes memory, 
 we should still be as ignorant as before how 
 that state contributes to memory. We 
 might have been so constituted, for anything 
 that I know, that the prick of a pin in the 
 hand, instead of causing pain, should cause 
 remembrance ; nor would that constitution 
 be more unaccountable than the present. 
 
 The body and mind operate on each other, 
 
 * Nothing more was meant by the philosopher in 
 question, than that memory is, as Reid himself ad. 
 mits, dependent on a certain state ot the brain, and 
 on some unknown effect determined in it, to w'lich 
 they gave the metaphorical name — impression, trace, 
 type, &c.— H. 
 
 [340-31-21
 
 CHAP. Vll.] 
 
 THEORIES CONCERNING iMEMORY. 
 
 355 
 
 according to fixed I'aws of nature ; and it is 
 the business of a philosopher to discover 
 those laws by observation and experiment : 
 but, when lie has discovered them, he must 
 rest in them as facts whose cause is in- 
 scrutable to the human understanding. 
 
 Mr Locke, and those who have followed 
 him, speak with more reserve than the 
 ancients,* and only incidentally, of impres- 
 sions on the brain as the cause of memory, 
 and impute it rather to our retaining in our 
 minds the ideas got either by sensation or 
 retlection. 
 
 This, Mr Locke says, may be done two 
 ways-^" First, By keeping tlie idea for some 
 time actually in view, which is called C07i- 
 temp/atiuu ; Secondly, By the power to re- 
 vive again in our minds those ideas which, 
 after imprinting, have disappeared, or have 
 been, as it were, laid out ot sight ; and this 
 is memory, which is, as it were, the store- 
 house of our ideas." [343] 
 
 To explain this' more distinctly, he imme- 
 diately adds the following observation : 
 
 " But our ideas being nothing but actual 
 perceptions in the mind, which cease to be 
 anything when there is no perception of 
 them, this laying up of our ideas in the 
 repository of the memory signifies no more 
 but this, that the mind has a power, in 
 many cases, to revive perceptions which it 
 once had, with this additional perception 
 annexed to them, that it has had them 
 before; and in this sense it is, that our ideas 
 are said to be in our memories, when indeed 
 they are actually nowhere; but only there 
 is an ability in the mind, when it will, to 
 revive them again, and, as it were, paint 
 them anew upon itself, though some with 
 more, some with less difficulty, some more 
 lively, and others more obscurely." 
 
 In this account of memory, the repeated 
 use of the phrase, as it were, leads one to 
 judge that it is partly figurative; we must 
 therefore endeavour to distinguish the fitru- 
 ralive part from the philosophical. The 
 first, being addressed to the imagination, 
 exhibits a picture of memory, which, to 
 have its efiect, must be viewed at a proper 
 distance and from a particular point of 
 view. The second, being addressed to the 
 understanding, ought to bear a near inspec- 
 tion and a critical examination. 
 
 The analogy between memory and a re- 
 pository, and between remembering and 
 retaining, is obvious, and is to be found in 
 all languages, it being very natural to ex- 
 press the operations of the mind by images 
 taken from things material. But, in phi- 
 losophy we ought to draw aside the veil of 
 imagery, and to view them naked. 
 
 When, therefore, memory is said to be a 
 repository or storehouse of ideas, where they 
 
 I* 'Ihvt iaiiardljr correct. 
 [34.3-. 3i5 J 
 
 Set" Notf K.— II. 
 
 are laid up when not perceived, and again 
 brought forth as there is occasion, I take 
 this to be popular and rhetorical. [344] 
 For the author tells us, that when they ure 
 not perceived, they are nothing, and no- 
 where, and therefore can neither be laid up 
 in a repository, nor drawn out of it. 
 
 But we are told, " That this laying up of 
 our ideas in the repository of the memory 
 signifies no more than this, that the mind 
 has a power to revive perceptions, which it 
 once had, with this additional perception 
 annexed to them, that it has had them 
 before." This, I think, must be understood 
 literally and philosophically. 
 
 But it seems to me as difficult to revive 
 things that have ceased to be anything, as 
 to lay them up in a repository, or to bring 
 them out of it. When a thing is once 
 annihilated, the same thing cannot be again 
 produced, though another thing similar to 
 it may. Mr Locke, in another place, 
 acknowledges that the same thing cannot 
 have two beginnings of existence ; and that 
 things that have different beginnings are 
 not the same, but diverse. From this it 
 follows, that an ability to revive our ideas 
 or perceptions, after they have ceased to be, 
 can signify no more but an ability to create 
 new ideas or perceptions similar to those we 
 had before. 
 
 They are said " to be revived, with this 
 additional perception, that we have had thera 
 before." 'I'his surely would be a fallacious 
 perception, since they could not have two 
 beginnings of existence : nor could we be- 
 lieve them to have two beginnings of exist- 
 ence. We can only believe that we had 
 formerly ideas or perceptions very like to 
 them, though not identically the same. But 
 w hether we perceive them to be the same, 
 or only like to those we had before, this 
 perception, one would think, sujtposes a 
 remembrance of those we had before, other- 
 wise the similitude or identity coidd not be 
 perceived. 
 
 Another phrase is used to explain this 
 reviving of our perceptions — " The mind, 
 as it were, ]>aints them anew upon itself.'' 
 [345] There may be someihing figurative 
 in this ; but, niaicing due allowance for that, 
 it must imply that the -mind, which paints 
 the things that have ceased to exist, must 
 have the memory of what they were, since 
 every painter nmst have a copy either before 
 his eye, or in his imagination and memory. 
 
 These remarks upon Mr Locke's account 
 of memory are intended to shew that his 
 system of ideas gives no light to this facidty, 
 but rather tends to darken it ; as little does 
 it make us understand how we remember, 
 and liy that means have tiie certain know- 
 le<Jge of things past. 
 
 Every man knows what memory is, and 
 has a distinct iiolioii d il. Itut when Mr
 
 356 
 
 ON THK INTELLECTUAL POWERS. 
 
 [essay ju. 
 
 Locke speaks of a power to revive in the 
 mind those ideas which, after imprinting, 
 have disappeared, or have been, as it were, 
 laid out of sight, one would hardly know 
 this to be memory, if he had not told us. 
 There are other things which it seems to 
 resemble at least as much. I see before 
 me the picture of a friend. I shut my eyes, 
 or turn them another way, and the picture 
 disappears, or is, as it were, laid out of sight. 
 I have a power to turn my eyes again to- 
 wards the picture, and immediately the per- 
 ception is revived. But is this memory ? 
 No surely ; yet it answers the definition as 
 well as memory itself can do. ' 
 
 We may observe, that the word percep- 
 tion is used by Mr Locke in too indefinite 
 a way, as well as the word idea. 
 
 Perception, in the chapter upon that sub- 
 ject, is said to be the first faculty of the 
 mind exercised about our ideas. Here we 
 are told that ideas are nothing but percep- 
 tions. Yet, I apprehend, it would sound 
 oddly to say, that perception is the first 
 faculty of the mind exercised about percep- 
 tion ; and still more strangely to say, that 
 ideas are the firet faculty of the mind ex- 
 ercised about our ideas. But why should 
 not ideas be a faculty as well as perception, 
 if both are the same ?-)- [346] 
 
 Memory is said to be a power to revive 
 our perceptions. Will it not follow from 
 this, that everything that can be remem- 
 bered is a perception ? If this be so, it will 
 be difficult to find anything in nature but 
 perceptions. ^: 
 
 Our ideas, we are told, are nothing but 
 actual perceptions ; but, in many places of 
 the Essay, ideas are said to be the objects 
 of perception, and that the mind, in all its 
 thoughts and reasonings, has no other im- 
 mediate object which it does or can con- 
 template but its own ideas. Does it not 
 appear from.this, either that Mr Locke neld 
 the operations of the mind to be the same 
 thing with the objects of those operations, § 
 or that he used the word idea sometimes in 
 one sense and sometimes in another, with- 
 out any intimation, and probably without 
 any apj)rehension of its ambiguity ? It is 
 an article of Mr Hume's philosophy, that 
 there is no distinction between the opera- 
 tions of the mind and their objects. § But 
 I see no reason to impute this opinion to 
 Mr Locke. I rather think that, notwith- 
 
 * To tome of the preceding" strictures on Locke's 
 account of memory, excuses might competently be 
 pleaded. — H. 
 
 t 1 his critirutn only shews the propriety of the 
 distinction of perception ar.d percept. Locke and 
 other.-|)liilosophers use the word perception, 1^, for 
 the act or faculty of perceiving ; '4°, lor that which is 
 perceived— the idea in their doctrine; and 3°, for 
 either orlioth indifferently. — H. 
 
 i. See above p. 222, b, note * ; p. 280, a. note*.— H. 
 
 ^ The term object being then . used lor the imme- 
 diate object— yiz., that of which we are conscious. 
 —H 
 
 standing his "great judgment and candour, 
 his understanding was entangled by the 
 ambiguity of the word idea, and that most 
 of the imperfections of his Essay are owing 
 to that cause. 
 
 Mr Hume saw farther into the conse- 
 quences of the common system concerning 
 ideas than any author had done before him. 
 He saw the absurdity of making every object 
 of thought double, and splitting it into a 
 remote object, which has a separate and 
 permanent existence, and an immediate 
 object, called an idea or impression, which 
 is an image of the former, and has no ex- 
 istence, but when we are conscious of it. 
 According to this system, we have no in- 
 tercourse with the external world, but by 
 means of the mternal world of ideas, which 
 represents the other to the mind. 
 
 He saw it was necessary to reject one 
 of these worlds as a fiction, and the question 
 was. Which should be rejected ? — whether 
 all mankind, learned and unlearned, had 
 feigned the existence of the external world 
 without good reason ; or whether philoso- 
 phers had feigned the internal world of ideas, 
 in order to account for the intercourse of 
 the mind with the external ? [347] Mr 
 Hume adopted the first of these opinions, 
 and employed his reason and eloquence in 
 support of it. 
 
 Bishop Berkeley had gone so far in the 
 same track as to reject the material world 
 as fictitious ; but it was left to Mr Hume 
 to complete the system. 
 
 According to his system, therefore, im- 
 pressions and ideas in his own mind are 
 the only things a man can know or can 
 conceive. Nor are these ideas representa- 
 tives, as they were in the old system. 
 There is nothing else in nature, or, at least, 
 within the reach of our faculties, to be re- 
 presented. What the vulgar call the per- 
 ception of an external object, is nothing but 
 a strong impression upon the mind. What 
 we call the remembrance of a past event, 
 is nothing but a present impression or idea, 
 weaker than the former. And what we call 
 imagination, is stUl a present idea, but 
 weaker than that of memory. 
 
 That I may not do him injustice, these 
 are his words in his " Treatise of Human 
 Nature," [vol. I.] page 193. 
 
 " We find by experience that, when any 
 impression has been present with the mind, 
 it again makes its appearance there as an 
 idea ; and this it may do after two different 
 ways, either when in its new appearance it 
 retains a considerable degree of its first 
 vivacity and is somewhat intermediate be- 
 twixt an impression and an.idea, or when it 
 entirely loses that vivacity, and is a perfect 
 idea. The faculty by which we repeat our 
 impressions in the first manner, is called 
 the memory, and the otherthe imagination." 
 
 [346, 347]
 
 CHAP. VII. 
 
 THEORIES CONCERNING MEMORY. 
 
 357 
 
 Upon this account of memory and imagi- 
 nation, I shall make some remarks. [348] 
 
 First, I wish to know what we are here 
 to understand by experience '^ It is said, 
 we find all this by experience ; and I con- 
 ceive nothing can be meant by this expe- 
 rience but memory — not that memory 
 which our author defines, but memory in 
 the common acceptation of the word. Ac- 
 cording to vulgar apprehension, memory is 
 an immediate knowledge of something past. 
 Our author does not admit that there is 
 any such knowledge in the human mind. 
 He maintains that memory is nothing but 
 a present idea or impression. But, in de- 
 fining what he takes memory to be, he takes 
 for granted that kind of memory whicli he 
 rejects. For, can we find by experience, 
 that an impression, after its first appearance 
 to the mind, makes a second and a third, with 
 different degrees of strength and vivacity, 
 if we have not so distnict a remembrance of 
 its first appearance as enables us to know 
 it upon its second and third, notwithstand- 
 ing that, in the interval, it has undergone 
 a very considerable change ?* 
 
 All experience supposes memory ; and 
 there can be no such thing as experience, 
 without trusting to our own memory, or 
 that of others. So that it appears, from 
 Mr Hume's account of this matter, that he 
 found himself to have that kind of memory 
 which he acknowledges and defines, by ex- 
 ercising that kind which he rejects. 
 
 Sciondl /, Wliat is it we find by expe- 
 rience or memory ? It is, " That, when an 
 impression has been present with the mind, 
 it again makes its appearance there as an 
 idea, and that after two different ways." 
 
 If experience informs us of this, it cer- 
 tainly deceives us ; for the thing is impos- 
 sible, and the author shews it to be so. 
 Impressions and ideas are fieeting, perish- 
 able things, which have no existence but 
 when we are conscious of them. If an im- 
 l)ression could make a sccoiid and a third 
 appearance t(j the mind, it must have a 
 continued existence during the interval of 
 these appearances, which Mr Hume ac- 
 knowledges to hit a gross absurdity. |34!>J 
 It seems, then, that we find, by experience, 
 a thing which is impossiljle- We are im- 
 posed upon by our experience, and made to 
 believe contradictions. 
 
 Perhaps it may be said, that these dif- 
 ferent appearances of the impression are not 
 to be understood literally, br.t figuratively; 
 that the impression is personified, and made 
 to appear at different times and in dittcrent 
 haljits, when no more is meant b.it that an 
 imjire.ssion apjiearsjit one time ; afterwards 
 a thing of a middle nature, between an im- 
 pression and an idea, which we call memory ; 
 
 f.3tH-3.y)] 
 
 ♦ .Sire Note D.—H. 
 
 and, last of all, a perfect idea, which we call 
 imagination : that this figurative meaning 
 agrees best with tlie last sentence of the 
 period, where we are told that memory and 
 imagination are faculties, whereby we repeat 
 our impresions in a more or less lively 
 manner. To repeat an impression is a figur- 
 ative way of speaking, which signifies maldng 
 a new impression similar to the former. 
 
 If, to avoid the absurdity implied in the 
 literal meaning, we understand the philo- 
 sopher in this figurative one, then his defini- 
 tions of memory and imagination, when 
 stripped of the figurative dress, will amount 
 to this. That memory is the faculty of 
 making a weak impression, and imagination 
 the fiiculty of making an impression still 
 weaker, after a corresponding strong one. 
 These definitions of memory and imagina- 
 tion labour under two defects : First, That 
 they convey no notion of the thing defined ; 
 and, Secondli/, That they may be applied to 
 things of a quite different nature from those 
 that are defined. 
 
 When we are said to have a faculty of 
 making a weak impression after a corre- 
 sponding strong one, it would not be easy 
 to conjecture that this faculty is memory. 
 Suppose a man strikes his head smartly 
 against the wall, this is an impression ; 
 now, he has a faculty by which he can 
 repeat this impression with less force, so 
 as not to hurt him : this, by Mr Hume's 
 account, must be memory. [350] He 
 has a faculty by which he can just touch 
 the wall with his head, so that the impres- 
 sion entirely loses its vivacity. This surely 
 must be imagination ; at least, it comes as 
 near to the definition given of it by Mr 
 Hume as anything I can conceive. 
 
 Thirdly, We may observe, that, when we 
 are told that we have a faculty of repeating 
 our impressions in a more or less lively 
 manner, this im])lics that we are the effi- 
 cient causes of our ideas of memory and 
 imagination ; but this contradicts what the 
 autiior says a little before, where he proves, 
 liy what he calls a convincing argument, 
 tliat impressions are the cause of their cor- 
 responding ideas. The argument that proves 
 tills had need, indeed, to be very con- 
 vincing ; whether we make the idea to be 
 a second appearance of the im]>ression, or a 
 new impression similar to the former. 
 
 Ifthe first bo true, then the impression 
 is the cause of itself. If the second then 
 the impression, after it is gone and has no 
 existence, ])roduccs the idea. Such arc the 
 mysteries of Mr Hume's i>hi!o.s()](hy. 
 
 It may be observed, that the connnon 
 system, I hat ideas are the only immediate 
 objects of thought, leads to Hcejiticism witJi 
 regard to memory, as well as with roganl to 
 tlie obj(!CtH of sense, wholhcr timMo ideas 
 are placed Lu the minil or in tlio brain.
 
 358 
 
 ON THE INTELLECTUAL POWERS, 
 
 []kSSAY 111. 
 
 Ideas are said to be things internal and 
 present, which have no existence but during 
 the moment they are in the mind. The 
 objects of sense are things external, which 
 hai^e a continued existence. When it is 
 maintained that all that we immediately 
 perceive is only ideas or phantasms, how 
 can we, from the existence of those phan- 
 tasms, conclude the existence of an external 
 world corresponding to them ? 
 
 This difficult question seems not to have 
 occurred to the Peripatetics. * Des Cartes 
 saw the difficulty, and endeavoured to find 
 out arguments by which, from the existence 
 of our phantasms or ideas, we might infer 
 the existence of external objects. [361] The 
 same course was followed by Malebranche, 
 Arnauld, and Locke ; but Berkeley and 
 Hume easily refuted all their arguments, 
 and demonstrated that there is no strength 
 in them. 
 
 The same difficulty with regard to mem- 
 ory naturally arises from the system of 
 ideas ; and the only reason why it was not 
 observed by philosophers, is, because they 
 give less attention to the memory than to 
 the senses ; for, since ideas are things pre- 
 sent, how can we, from our having a certain 
 idea presently in our mind, conclude that an 
 event really happened ten or twenty years 
 ago, corresponding to it ? 
 
 There is the same need of arguments to 
 prove, that the ideas of memory are pictures 
 of things that really did happen, as that the 
 ideas of sense are pictures of external objects 
 which now exist. In both cases, it will be 
 impossible to find any argument that has 
 real weight. So that this hypothesis leads 
 us to absolute scepticism, with regard to 
 those things which we most distinctly re- 
 member, no less than with regard to the 
 external objects of sense. 
 
 It does not appear to have occurred either 
 to Locke or to Berkeley, that their system 
 has the same tendency to overturn the tes- 
 timony of memory as the testimony of the 
 senses. 
 
 Mr Hume saw farther than both, and 
 found this consequence of the system of 
 ideas perfectly corresponding to his aim of 
 establishing universal scepticism. His sys- 
 stem is therefore more consistent than 
 theirs, and the conclusions agree better with 
 the premises. 
 
 But, if we should grant to Mr Hume that 
 our ideas of memory afford no just ground 
 to believe the past existence of things which 
 we remember, it may still be asked. How it 
 
 * This is not correct. See above, p. 285, note t- 
 To that note I may add, that no orthodox Catholic 
 could be an Idealist. It was only the doctrine of 
 transsubstantiation that prevented Malebranche from 
 pre-occupying the theory of Berkeley and Collier, 
 which was in fact his own, with the transcendent 
 reality of a material world left out, as a Protestant 
 hors d'lTHvre. This, it is curious, has never been 
 observed. See Note P. — H. 
 
 comes to pass that perception and memory 
 are accompanied with belief, while bare ima- 
 gination is not ? Though this belief can- 
 not be justified upon his system, it ought to 
 be accounted for as a phaeuomenon of hu- 
 man nature. [352] 
 
 This he has done, by giving us a new 
 theory of belief in general ; a theory which 
 suits very well with that of ideas, and seems 
 to be a natural consequence of it, and which, 
 at the same time, reconciles all the belief 
 that we find in human nature to perfect 
 scepticism. 
 
 What, then, is this belief? It must 
 either be an idea, or some modification of 
 an idea ; we conceive many things which we 
 do not believe. The idea of an object is 
 the same whether we believe it to exist, or 
 barely conceive it. The belief adds no new 
 idea to the conception ; it is, therefore, no- 
 thing but a modification of the idea of the 
 thing believed, or a different manner of 
 conceiving it. Hear himself : — 
 
 " All the perceptions of the mind are of 
 two kinds, impressions and ideas, which 
 differ from each other only in their different 
 degrees of force and vivacity. Our ideas 
 are copied from our impressions, and repre- 
 sent them in all their parts. When you 
 would vary the idea of a particular object, 
 you can only increase or diminish its force 
 and vivacity. If you make anyother change 
 upon it, it represents a different object or 
 impression. The case is the same as in 
 colours. A particular shade of any colour 
 may acquire a new degree of liveliness or 
 brightness, without any other variation ; 
 but, when you produce any other variation, 
 it is no longer the same shade or colour. So 
 that, as belief does nothing but vary the 
 manner in which we conceive any object, it 
 can only bestow on our ideas an additional 
 force and vivacity. An opinion, therefore, 
 or belief, may be most accurately defined a 
 lively idea, related to or associated with a 
 present impression.'' 
 
 This theory of belief is very fruitful of 
 consequences, which Mr Hume traces with 
 his usual acuteness, and brings into the 
 service of his system. [353] A great part 
 of his system, indeed, is built upon it ; and 
 it is of itself sufficient to prove what he 
 calls his hypothesis, " that belief is more 
 properly an act of the sensitive than of 
 the cogitative part of our natures." 
 
 It is very difficult to examine this ac- 
 count of belief with the same gravity with 
 which it is proposed. It puts one in 
 mind of the ingenious account given by 
 Martinus Scriblerus of the power of syllo- 
 gism, by making the major the male, and 
 the minor the female, which, being couplea 
 by the middle term, generate the conclusion. 
 There is surely no science in which men oi 
 great parts and ingenuity have fal?en into
 
 CHAP. Vll.] 
 
 THEORIES CONCERNING MEMORY. 
 
 359 
 
 such gross absurdities as in treating of the 
 powers of the mind. I caujiot help think- 
 ing that never anything more absurd was 
 gravely maintained by any philosopher, 
 than this account of the nature of belief, 
 and of the distinction of perception, memory, 
 and imagination. 
 
 The belief of a proposition is an opera- 
 tion of mind of which every man is con- 
 scious, and what it is he understands per- 
 fectly, though, on account of its simplicity, 
 he cannot give a logical definition of it. If 
 he compares it with strength or vivacity of 
 his ideas, or with any modification of ideas, 
 they are so far from appearing to be one 
 and the same, that they have not the least 
 similitude. 
 
 That a strong belief and a weak belief 
 differ only in degree, I can easily compre- 
 hend ; but that belief and no belief should 
 differ only in degree, no man can believe 
 who understands what he speaks. For this 
 is, in reality, to say that something and 
 nothing differ only in degree ; or, that 
 nothing is a degree of something. 
 
 Every proposition that may be the ob- 
 ject of belief, has a contrary proposition 
 that may be the object of a contrary belief. 
 The ideas of both, according to Mr Hume, 
 are the same, and differ only in degrees of 
 vivacity — that is, contraries differ only in 
 degree ; and so pleasure may be a degree 
 of pain, and hatred a degree of love. [354] 
 But it is to no purpose to trace the absurd- 
 ities that follow from this doctrine, for none 
 of them can be more absurd than the doc- 
 trine itself. 
 
 Every man knows perfectly what it is to 
 see an object with his eyes, what it is to 
 remember a past event, and what it is to 
 conceive a thing which has no existence. 
 That these are quite different operations of 
 liis mind, he is as certain as that sound 
 differs from colour, and both from taste ; 
 ijnd I can as easily believe that sound, and 
 colour, and taste differ only in degree, as 
 that seeing, and remembering, and imagin- 
 ing, differ only in degree. 
 
 Mr Hume, in the third volume of his 
 " Treatise of Human Nature," is sensible 
 that his theory of belief is liable to strong 
 objections, and seems, in some measure, to 
 retract it ; but in what measure, it is not 
 easy to say. He seems still to think that 
 belief is only a modification of the idea ; 
 but that vivacity is not a proper term to 
 express that modification. Instead of it, 
 he uses some analogical ]>hrasos, to ex|>l:iin 
 that modification, such as " apprehending 
 the idea more strongly, or taking faster 
 hold of it." 
 
 'I'liere is nothing more meritorious in a 
 philosopher tliau to r<'tract an error upon 
 conviction ; but, in this instance, J hum- 
 bly ajipreliend Mr Hume claims that nierit 
 
 |:{.ii-;{.i(n 
 
 upon too shght a ground. For I cannot 
 perceive that the apprehending an idea 
 more strongly, or taking faster hold of it, 
 expresses any other modification of the idea 
 than what was before expressed by its 
 strength and vivacity, or even that it ex- 
 presses the same modification more pro- 
 perly. Whatever modification of the idea 
 he makes belief to be, whether its vivacity, 
 or some other without a name, to make 
 perception, memory, and imagination to be 
 the different degrees of that modification, 
 is chargeable with the absurdities we have 
 mentioned. 
 
 Before we leave this subject of memory, 
 it is proper to take notice of a distinction 
 which Aristotle makes between memory 
 and reminiscence, because the distinction 
 lias a real foundation in nature, though in 
 our language, I think, we do not distinguish 
 them by different names. [355] 
 
 Memory is a kind of habit which is not 
 always in exercise with regard to things we 
 remember, but is ready to suggest them 
 when there is occasion. The most perfect 
 degree of this habit is, when the thing pre- 
 sents itself to our remembrance spontane- 
 ously, and without labour, as often as there 
 is occasion. A second degree is, when the 
 thing is forgot for a longer or shorter time, 
 even when there is occasion to remember 
 it ; yet, at last, some incident brings it to 
 mhid without any search. A third degree 
 is, when we cast about and search for what 
 we would remember, and so at last find it 
 out. It is this last, I think, which Ari- 
 stotle calls reminiscence, as distinguished 
 from memory. 
 
 Reminiscence, therefore, includes a will 
 to recollect something past, and a search for 
 it. But here a difficulty occurs. It may 
 be said, that what we will to remember we 
 must conceive, as there can be no will with- 
 out a ccnceptica of the thing willed. A 
 will to remember a thing, therefore, seems 
 to imply that we rememlur it already, and 
 have no occasion to search for it. But this 
 difficulty is easily removed. When we will 
 to remember a thing, we nnist remember 
 something relating to it, which gives us a 
 relative conception of it ; but we may, at 
 the same time, have no conception what the 
 thing is, but only what relation it bears to 
 something else. Thus, I remember that a 
 friend charged me with a commission to be 
 executed at such a pl:u-c ; but 1 have forgot 
 what the commission was. By ai>piying 
 my thought to what 1 remember conci-rning 
 it, that it was given by sni-li a i)erson, upon 
 such an occasion, in consiMiumcf <if surb a 
 conversation, I nm led, in a train of thought, 
 to the very thing 1 had forgot, and recol- 
 lect distinctly what the coininihsion was. 
 
 [:i5(il 
 
 Aristotle says, that brutes linve not rt-
 
 360 
 
 ON THE INTELLECTUAL POWERS. 
 
 [essay IV 
 
 miniscence ;* and this I think is probable ; 
 but, says he, they have memory. It cannot, 
 indeed, be doubted but they have something 
 very like to it, and, in some instances, in a 
 very great degree. A dog knows his master 
 after long absence. A horse will trace back 
 a road he has once gone, as accurately as a 
 man ; and this is the more strange, that the 
 train of thought which he had in going must 
 be reversed in his return. It is very like 
 to some prodigious memories we read of, 
 where a person, upon hearing an hundred 
 names or unconnected words pronounced, 
 can begin at the last, and go backwards to 
 
 the first, without losing or misplacing one. 
 Brutes certainly may learn much from ex- 
 perience, which seems to imply memory. 
 
 Yet, I see no reason to think that brutes 
 measure time as men do, by days, months, 
 or years ; or that they have any distinct 
 knowledge of the interval between things 
 which they remember, or of their distance 
 from the present moment If we could not 
 record transactions according to their dates, 
 human memory would be something very 
 different from what it is, and, perhaps, re- 
 semble more the memory of brutes. [357] 
 
 ESSAY IV. 
 
 OF CONCEPTION. 
 
 CHAPTER L 
 
 OF CONCEPTION, OR SIMPLE APPREHENSION IN 
 GENERAL. 
 
 Conce'iv'mg, imagining,-^- apprehending, un- 
 derstanding, having a notion of a thing, are 
 common words, used to express that opera- 
 tion of the understanding which the logi- 
 cians call simple apprehension. The having 
 an idea of a thing, is, in common language, 
 used in the same sense, chiefly, I think, 
 since Mr Locke's tinie.+ 
 
 Logicians define Simple Apprehension to 
 be the bare conception of a thing without 
 any judgment or belief about it. If this 
 were intended for a strictly logical definition, 
 it might be a just objection to it, that con- 
 ception and apprehension are only synony- 
 mous words ; and that we may as well 
 define conception by apprehension, as appre- 
 hension by conception ; but it ought to be 
 
 * This is a question which may be differently an. 
 iwered, according as we attribute a different meaning 
 to the terms employed. — H. 
 
 t Jmapi)U7t</ tl:ou\d not be confounded with Con. 
 ceiving, *&c. ; "(hough some philosophers, as Ga>scndi, 
 have not attended to the distinction. The word* 
 Conception, Concept, Notion, should be limited to the 
 thought of what cannot be represented in the imagin. 
 ation, as. the thou^jht .suggested by a general term. 
 The Lcibnitzians call this symbolical in contras-tto 
 intuitive knowledge. This is the sense 'in which 
 conceptio-awi conceptus have been usu;illy and cor- 
 rectly employed. Wr Stewart, on the other hand, 
 arbitratily limits Conception to the reproduction, in 
 imagination, of an object rf jense as actually per. 
 ceived. See Elements, vol. 1., ch. iii. I cannot 
 enter on a genetal criticism of Reid's nomenclature, 
 thrugh I may say something more of this in the 
 sequel. See below, under pp. 371, 48^. — H. 
 
 t In this countrij should be added, l.ocke only 
 introduced into En<jlish philosophy the teim idea in 
 its Cartesian universality. Prior to him, the «ord 
 waa only used with us in its Platonic signification. 
 Before Des Cartes, David Buchanan, a Scotch philo. 
 sopher, who sojourned in France, had, however, em. 
 ployed Idea in an equal latitude. See Note 0.- H. 
 
 remembered that the most simple operations 
 of the mind cannot be logically defined. To 
 have a distinct notion of them, we must 
 attend to them as we feel them in our own 
 minds. He that would have a distinct 
 notion of a scarlet colour, will never attain 
 it by a definition ; he must set it before his 
 eye, attend to it, compare it with the colours 
 that come nearest to it, and observe the 
 sjiecific diffeience, which he will in vain 
 attempt to define.* [358] 
 
 Every man is conscious that he can con- 
 ceive a thousand things, of which he believes 
 nothing at all — as a horse with wings, a 
 mountain of gold ; but, although concep- 
 tion may be without any degree of belief, 
 even the smallest belief cannot be without 
 conception. He that believes must have 
 some conception of what he believes. 
 
 Without attempting a definition of this 
 operation of the mind, I shall endeavour to 
 explain some of its properties ; consider the 
 theories about it ; and take notice of some 
 mistakes of philosophers concerning it. 
 
 1. It may be observed that conception 
 enters as an ingredient in every operation 
 of the mind. Our senses cannot give us the 
 belief of any object, without giving some 
 conception of it at the same time. No man 
 can either rememberer reason about things 
 of which he hatli no conception. When 
 we will to exert any of our active powers, 
 there must be some conception of what we 
 will to do. There can be no desire nor 
 aversion, love nor hatred, without some con- 
 ception of the object. We cannot feel pain 
 without conceiving it, though we can con- 
 ceive it without feeling it. These things 
 are self-evident. 
 
 In every operation of the mind, there- 
 
 * We do not define the specific difference, but we 
 define by it. — H. 
 
 [.S57, 3f;S]
 
 CHAP. I.] OF SIMPLE APPREHENSIOxN IN GENERAL. 
 
 3(jl 
 
 fore, iu everything we call thought, there 
 must be conception. When we analyse the 
 various operations either of the understand- 
 ing or of the will, we shall always find this 
 at the bottom, like the caput nwrtnian of 
 the cheuiists, or the materia prima of the 
 Peripatetics ; but, though there is no opera- 
 tion of mind without conception, yet it may 
 be found naked, detached from all others, 
 and then it is called simple apprehension, or 
 the bare conception of a thing. 
 
 As all the operations of our mind are ex- 
 pressed by language, every one knows that 
 it is one thing to understand what is said, 
 to conceive or apprehend its meaning, 
 whether it be a word, a sentence, or a dis- 
 course ; it is another tliLug to judge of it, 
 to assent or dissent, to be persuaded or 
 moved. The first is 'simple apprehension, 
 and may be without the last ; but the last 
 cannot be without the first. ^ [359] 
 
 2. In bare conception there can neither 
 be truth nor falsehood, because it neither 
 affirms nor denies. Every judgment, and 
 every proposition by which judgment is 
 expressed, must be true or false ; and the 
 qualities of true and false, in their proper 
 sense, can belong to nothing but to judg- 
 ments, or to propositions which express 
 judgment. In the bare conception of a 
 thing there is no judgment, opinion, or be- 
 lief included, and therefore it cannot be 
 either true or false. 
 
 But it may be said. Is there anything 
 more certain than that men may have true 
 or false conceptions, true or false appre- 
 hensions, of things ? I answer, that such 
 ways of speaking are indeed so common, 
 and so well authorized by custom, the arbiter 
 of language, that it would be presumption 
 to censure them. It is hardly possible to 
 avoid using them. But we ought to be 
 upon our guard that we be not misled by 
 them, to confound things which, though 
 often expressed by the same words, are 
 really different. We must therefore re- 
 member what was before observed, Essay I. 
 chap. I — that all the words by which we 
 signify the bare conception of a thing, are 
 likewise used to signify our opinions, when 
 we wish to express them witii modesty and 
 diffidence. And we shall always find, that, 
 when we speak of true or false concejitions, 
 we mean true or false opinions. An opinion, 
 though ever so wavering, or ever so mo- 
 destly expressed, must be either true or 
 false ; but a bare conception, wliicli ex- 
 presses no opinion or judgment, can be 
 iieitiier. 
 
 If we analyse those speeches in which 
 men attribute truth or falsehood to our 
 conceptions of things, we shall find in every 
 case, that there is some ojiinion or judgincMit 
 implied in what they will conccptioii. |.'U;((| 
 A child conceives the moon to be flat, and n 
 [.1.^<)-.'}«1] 
 
 foot or two broad — that is, this is his opinion : 
 and, when we say it is a false notion or a 
 false conception, we mean that it is a false 
 opinion. He conceives the city of London 
 to be like his country village — that is, he 
 believes it to be so, till he is better instructed. 
 He conceives a lion to have horns ; that is, 
 he believes that the animal which men call 
 a lion, has horns. Such opinions language 
 authorizes us to call conceptions ; and they 
 may be true or false. But bare conception, 
 or what the logicians call simple apprehen- 
 sion, implies no opinion, however slight, 
 and therefore can neither be true nor false. 
 
 What Mr Locke says of ideas (by which 
 word he very often means nothing but con- 
 ceptions) is very just, when the word idea 
 is so understood. Book II., chap, xxxii., § 1, 
 " Though truth and falsehood belong in 
 propriety of speech only to propositions, yet 
 ideas are often termed true or false (as 
 what words are there that are not used with 
 great latitude, and with some deviation 
 from their strict and proper signification ?) 
 though I think that when ideas themselves 
 are termed true or false, there is still some 
 secret or tacit proposition, which is the 
 foundation of that deuomination : as we shall 
 see, if we examine the particular occasions 
 wherein they come to be called true or false ; 
 in all which we shall find some kind of 
 affirmation or negation, which is the reason 
 of that denomination ; for our ideas, being 
 nothing but bare appearances, or perceptions 
 in our minds, cannot properly and simply 
 in themselves be said to be true or false, no 
 more than a simple name of anything can 
 be .said to be true or false." 
 
 It may be here observed, by the way, that, 
 in this passage, as in many others, Mr 
 Locke uses the word percrptinii, as well ;is 
 the word idea, to signify what I call con- 
 ception, or simple apprehension. And in 
 his chapter upon perception. Book 1 1., chap, 
 ix., he uses it in the same sense. Pereip- 
 tion, he says, " as it is the first faculty of 
 the mind, exercised about our ideas, so it 
 is the first and simplest idea we have Irom 
 reflection, and is by some called thinking 
 in general. ['Ml] It seems to be that 
 which puts the distinction betwixt the ani- 
 mal kingdom and the inferior parts of nat re. 
 It is the first operation of all our faculties, 
 and the inlet of all knowlediio into our 
 minds." 
 
 Mr Locke has followed the example given 
 by Des Cartes, Gassendi, and other Carte- 
 sians,' in giving the name of peicrptinn to 
 the bare conception of tilings : and he has 
 been followed in this by Bishop Berkeley, 
 
 * GaMi-nditvai not n Carictian, l)iit an Aiiti-Cur 
 tcsian ihouRh he aduplcil Revcrul pointii in liii iilii- 
 losoi.liv fiom ;)i-i t nrtcd— tor fxaiiuili', tlic fiiiploy- 
 lurni 1)1 ilu- iiTRi I'tea 111)1 in \U riaionic liiintalmn. 
 — II.
 
 362 
 
 ON THE INTELLECTUAL POWERS. 
 
 QessAY IV. 
 
 Mr Hume, and many late philosophers, 
 when they treat of ideas. They have pro- 
 bably been led into this impropriety, by the 
 common doctrine concerning- ideas, which 
 teaches us, that conception, perception by 
 the senses, and memory, are only different 
 ways of perceiving ideas in our own minds. • 
 If that theory be well founded, it will in- 
 deed be very difficult to find any specific 
 distinction between conception;and percep- 
 tion. -f* But there is reason to distrust any 
 philosophical theory when it leads men to 
 corrupt language, and to confound, under 
 one name, operations of the mind which 
 common sense and common language teach 
 them to distinguish. 
 
 I grant that there are some states of the 
 mind, wherein a man may confound his 
 conceptions with what he perceives or re- 
 members, and mistake the onefor the other; 
 as in the delirium of a fever, in some cases 
 of lunacy and of madness, in dreaming, and 
 perhaps in some momentary transports of 
 devotion, or of other strong emotions, which 
 cloud his intellectual faculties, and, for a 
 time, carry a man out of himself, as we 
 usually express it. 
 
 Even in a sober and sound state of mind, 
 the memory of a thing may be so very weak 
 that we may be in doubt whether we only 
 dreamed or imagined it. 
 
 It may be doubted whether children, 
 when their imagination first begins to work, 
 can distinguish what they barely conceive 
 from what they remember. [362] I have 
 been told, by a man of knowledge and ob- 
 servation, that one of his sons, when he 
 began to speak, very often told lies with 
 great assurance, without any intention, as 
 far as appeared, or any consciousness of 
 guilt. From which the father concluded, 
 that it is natural to some children to lie. 
 I am rather inclined to think that the child 
 had no intention to deceive, but mistook the 
 rovings of his own fancyfor things which 
 he remembered.:}: This, however, I take 
 to be very uncommon, after children can 
 communicate their sentiments by language, 
 though perhaps not so in a more early 
 period. 
 
 Granting all this, if any man will affirm 
 that they whose intellectual faculties are 
 sound, and sober, and ripe, cannot with 
 certainty distinguish what they perceive or 
 remember, from what they barely conceive, 
 when those operations have any degree of 
 strength and distinctness, he may enjoy his 
 
 * But see above, p. 280, a, note * et<iim.— Vi. 
 
 \ Yet Rfid himgelf defines Perreptioii, a Concep- 
 lion (tmagination) accompanied with a belief in the 
 existence of its object ; and Mr Stewart reduces the 
 specific difference, at best only a concomitant, to an 
 accidental circumstance, in holding tlint our im. 
 aginations are themselves conjoined with a tempo, 
 rary belief in their objective reality. H. 
 
 : But conipaie above, p. 3*0, col. a.— IJ. 
 
 opinion ; I know not how to reason with 
 him. Why should philosophers confound 
 those operations in treating of ideas, when 
 they would be ashamed to do it on other 
 occasions? To distinguish the various 
 powers of our minds, a certain degree of 
 understanding is necessary. And if some, 
 through a defect of understanding, natural 
 or accidental, or from unripeness of under- 
 standing, may be apt to confound different 
 powers, will it follow that others cannot 
 clearly distinguish them ? 
 
 To return from this digression — into which 
 the abuse of* the word perception, by philo- 
 sophers, has led me — it appears evident that 
 the bare conception of an object, which 
 includes no opinion or judgment, can neither 
 be true nor false. Those qualities, in their 
 proper sense, are altogether inapplicable to 
 this operation of the mind. 
 
 3. Of all the analogies between the opera- 
 tions of body and those of the mind, there 
 is none so strong and so obvious to all man- 
 kind as that which there is between paint- 
 ing, or other plastic arts, and the power of 
 conceiving objects in the mind. Hence, in 
 all languages, the words by which this power 
 of the mind and its various modifications 
 are expressed, are analogical, and borrowed 
 from those arts. [363] We consider this 
 power of the mind as a plastic power, by 
 which we form to ourselves images of the 
 objects of thought. 
 
 In vain should we attempt to avoid this 
 analogical language, for we have no other 
 language upon the subject ; yet it is danger- 
 ous, and apt to mislead. All analogical and 
 figurative words have a double meaning ; 
 and, if we are not very much upon our 
 guard, we slide insensibly from the bor- 
 rowed and figurative meaning into the pri- 
 mitive. We are prone to carry the parallel 
 between the things compared farther than it 
 will hold, and thus very naturally to fall 
 into error. 
 
 To avoid this as far as possible in the pre- 
 sent subject, it is proper to attend to the 
 dissimilitude between conceiving a thing in 
 the mind, and painting it to the eye, as weD 
 as to their similitude. The similitude strikes 
 and gives pleasure. The dissimilitude we 
 are less disposed to observe ; but the philo- 
 sopher ought to attend to it, and to carry it 
 always in mind, in his reasonings on this 
 subject, as a monitor, to warn him against 
 the errors into which the analogical lan- 
 guage is apt to draw him. 
 
 When a man paints, there is some work 
 done, which remains when his hand is taken 
 off, and continues to exist though he should 
 think no more of it. Every stroke of his 
 pencil produces an effect, and this effect is 
 different from his action in making it ; for 
 it remains and continues to exist when the 
 action ceases. The action of painting is 
 
 1 ;i62, 6331
 
 CHAP. 1.1 OF SIMPLE APPREHENSION IN GENERAL. 
 
 363 
 
 one thing ; the picture produced is another 
 thing. The first is the cause, the second is 
 the effect. 
 
 Let us next consider what is done when 
 he only conceives this picture. He must 
 have conceived it before he painted it ; for 
 this is a maxim universally admitted, that 
 every work of art must first be conceived in 
 the mind of the operator. What is this 
 conception ? It is an act of the mind, a kind 
 of thought. This cannot be denied. [36'4] 
 But does it produce any effect besides the 
 act itself ? Surely conmion sense answers 
 this question in the negative ; for every 
 one knows that it is one thing to conceive, 
 another thing to .bring forth into eflect- It 
 is one thing to project, another to execute. 
 A man may think for a long time what he 
 is to do, and after all do nothing. Con- 
 ceiving, as well as projecting or resolving, 
 are what the schoolmen called immonent acts 
 of the mind, which produce nothing beyond 
 themselves. But painting is a transitive 
 act, which produces an effect distinct from 
 the operation, and this effect is the picture. 
 Let this, therefore, be always remembered, 
 that what is commonly called the image of 
 a thing in the mind, is no more than the 
 act or operation of the mind in conceiving 
 it. 
 
 That this is the common sense of men 
 who are untutored by philosophy, appears 
 from their language. If one ignorant of the 
 language should ask, What is meant by 
 conceiving a thing ? we should very natur- 
 ally answer, that it is having an image of 
 it in the mind — and perhaps we could not 
 explain the word better. This shews that 
 conception, and the image of a thing in the 
 mind, are synonymous expressions. The 
 image in the mind, therefore, is not the 
 object of conception, nor is it any effect 
 produced by conception as a cause. It is 
 conception itself. That very mode of think- 
 ing winch we call conception, is by another 
 name called an image in the mind.* 
 
 Nothing more readily gives the concep- 
 tion of a thing than the seeing an image of 
 it. Hence, by a figure common in language, 
 conception is called an image of the thing 
 conceived. But to shew tliat it is not a 
 real but a metai)horical image, it is called 
 an image in the mind. We know nothing 
 that is properly in the mind but thought ; 
 and, when anything else is said to be in the 
 mind, the expression must be figurative, 
 and signify some kind of thought. [lUiiJ] 
 I know that philosophers very unani- 
 mously maintain, that in conception there 
 
 * We ou)!ht, how( ver, to distinguifih Imfutination 
 and Imajie, Cuncijition and C(Hio)il. Imagination 
 and Conception ought to beemploytfl in spraking of 
 the mental modification, one and indivibihlc, con. 
 •idtred ai. an act; Image and tonitpt, in HH-aking 
 of It, conkidcred as a product or immciiiatc object. — 
 
 a 
 
 I,.36i-36«J 
 
 is a real image in the mind, which is the 
 immediate object of conception, and distinct 
 from the act of conceiving it. I beg the 
 reader's indulgence to defer what may be 
 said for or against this philosophical opinion 
 to the next chapter ; intending in this only 
 to explain what appears to me to belong to 
 this operation of mind, without considering 
 the theories about it. I think it appears, 
 from what has been said, that the common 
 language of those who have not imbibed any 
 philosophical opinion upon this subject, 
 authorizes us to understand the conception 
 of a thine/, and an image of it in the minri, 
 not as two different things, but as two dif- 
 ferent expressions, to signify one and the 
 same thing ; and I wish to use common 
 words in their common acceptation. 
 
 4, Taldng along with us what is said in 
 the last article, to guard us against the se- 
 duction of the analogical language used on 
 this subject, we may observe a very strong 
 analogy, not only between conceiving and 
 painting in general, but between the dif- 
 ferent kinds of our conceptions, and the 
 different works of the painter. He either 
 makes fancy pictures, or he copies from the 
 painting of others, or he paints from the 
 life ; that is, from real objects of art or 
 nature which he has seen. I think our 
 conceptions admit of a division very similar. 
 
 First, There are conceptions which may 
 be called fancy pictures. They are com- 
 monly called creatures of fancy, or of im- 
 agination. They are not the copies of any 
 original that exists, but are originals them- 
 selves. Such was the conception which 
 Swift formed of the island of Laputa, and 
 of the country of the Lilliputians ; Cer- 
 vantes of Don Quixote and his Squire ; 
 Harrington of the Government of Oceana ; 
 and Sir Thomas 3Iore of that of Utopia. 
 We can give names to such creatures of 
 imagination, conceive them distinctly, and 
 reason consequentially concerning them, 
 though they never had an existence. They 
 were conceived by tbeir creators, and may 
 be conceived by others, but they never 
 existed. We do not ascribe the qualities 
 of true or false to them, because tliey are 
 not accompanied with any belief, nor do tlioy 
 imply any affirmation or negation. [\MU'>] 
 
 Setting aside those creatures of imagina- 
 tion, there are other concejjtions, wliicli 
 may be called copies, because they have an 
 original or archetype to which they refer, 
 and with which tliey are believed to agree ; 
 ai.d we call tlicni true or fal^e cunceplions, 
 according as tlicy agree or disagree with 
 the standard to wliicli tliey are referred. 
 These are of two kinds, which have dillereut 
 standards or originals. 
 
 'I'lie fir.\t kiiiil is analogous to pictures 
 taken from the life. We have conceptionB 
 (if individual things tliat nally exist, snch
 
 364 
 
 ON THE INTELLECTUAL POWERS. 
 
 Les«ay )V. 
 
 5S the city of London, or the government 
 of Venice. Here the things conceived are 
 the originals ; and our conceptions are called 
 true when they agree with the thing con- 
 ceived. Thus, my conception of the city of 
 London is true, when I conceive it to be 
 what it really is. 
 
 Individual things which really exist, 
 being the creatures of God, (though some 
 of them may receive their outward form 
 from man,) he only who made them knows 
 their whole nature ; we know them but in 
 part, and therefore our conceptions of them 
 must in all cases be imperfect and inade- 
 quate ; yet they may be true and just, as 
 far as they reach. 
 
 The second kind is analogous to the copies 
 which the painter makes from pictures done 
 before. Such I think are the conceptions 
 we have of what the ancients called univer- 
 eals ; that is, of things which belong or may 
 belong to many individuals. These are 
 kinds and species of things ; such as man 
 or elephant, which are species of substances; 
 wisdom or courage, which are species of 
 qualities ; equality or similitude, which are 
 species of relations.* It may be asked — 
 J'rom what original are these conceptions 
 formed ? And when are they said to be 
 true or false? [367] 
 
 It appears to me, that the original from 
 which they are copied — that is, the thing 
 conceived — is the conception or meaning 
 which other men, who understand the 
 langua;^e, affix to the same words. 
 
 Things are parcelled into kinds and sorts, 
 not by nature, but by men. The individual 
 things we are connected with, are so many, 
 that to give a proper name to every indi- 
 vidual would be impossible. We could 
 never attain the knowledge of them that is 
 necessary, nor converse and reason about 
 them, without sorting them according to 
 the> different attributes. Those that agree 
 in certain attributes are thrown into one 
 parcel, and have a general name given 
 them, which belongs equally to every indi- 
 vidual in that parcel. This common name 
 must therefore signify those attributes 
 which have been observed to be common 
 to every individual in that parcel, and no- 
 thing else. 
 
 That such general words may answer 
 their intention, all that is necessary is, that 
 those who use them should affix the same 
 meaning or notion — that is, the same con- 
 ception to them. The common meaning is 
 the standard by which such conceptions are 
 formed, and they are said to be trye or 
 
 * Of all such we can have no adequate imagination. 
 A universal, when represented in imagination, is no 
 longer adequate, no longer a universal. We. cannot 
 have an imafje of Horse, b'ltonly of some individual 
 of that species We may, however, have a notion or 
 conception of it. See below, p. 48^. — H. 
 
 false according as they agree or disagree 
 with it. Thus, my conception of felony is 
 true and just, when it agrees with the 
 meaning of that word in the laws relating 
 to it, and in authors who understand the 
 law. The meaning of the word is the 
 thing conceived ; and that meaning is the 
 conception affixed to it by those who best 
 understand the language. 
 
 An individual is expressed in languaga 
 either by a proper name, or by a general 
 word joined to such circumstances as dis- 
 tinguish that individual from all others ; if 
 it is unknown, it may, when an object of 
 sense, and within reach, be pointed out to 
 the senses ; when beyond the reach of the 
 senses, it may be ascertained by a descrip- 
 tion, which, though very imperfect, may be 
 true, and sufficient to distinguish it from 
 every other individual. Hence it is, that, 
 in speaking of individuals, we are very little 
 in danger of mistaking the object, or tak- 
 ing one individual for another. [368] 
 
 Yet, as was before observed, our concep- 
 tion of them is always inadequate and lame. 
 They are the creatures of God, and there 
 are many things belonging to them which 
 we know not, and which cannot be deduced 
 by reasoning from what we know. They 
 have a real essence, or constitution of 
 nature, from which all their qualities flow ; 
 but this essence our faculties do not com- 
 j)rehend. They are therefore incapable of 
 definition ; for a definition ought to com- 
 prehend the whole nature or essence of the 
 thing defined. 
 
 Thus, Westminster Bridge is an indi- 
 vidual object ; though I had never seen 
 or heard of it before, if I am only made 
 to conceive that it is a bridge from West- 
 minster over the Thames, this concep- 
 tion, however imperfect, is true, and is 
 sufficient to make me distinguish it, when 
 it is mentioned, from every other object 
 that exists. The architect may have an 
 adequate conception of its structure, which 
 is the work of man ; but of the materials, 
 which are the work of God, no man has an 
 adequate conception ; and, therefore, though 
 the object may be described, it cannot be 
 defined. 
 
 Universals are always expressed by gene- 
 ral words ; and all the words of language, 
 excepting proper names, are general words ; 
 they are the signs of general concep- 
 tions, or of some circumstance relating 
 to them. These general conceptions are 
 formed for the purpose of language and 
 reasoning ; and the object from which they 
 are taken, and to which they are intended 
 to agree, is the conception which other men 
 join to the same words; they may, there- 
 fore, be adequate, and perfectly agree with 
 the thing conceived. This implies ,no more 
 than that men who speak the same language 
 
 IS67, 368]
 
 CHAP. I.] OF SIMPLE APPREHENSION IN GENERAL. 
 
 365 
 
 may perfectly agree in the meaning of 
 many general words. 
 
 Thus mathematicians have conceived 
 what they call a plane triangle. They 
 have defined it accurately ; and, when I 
 conceive it to be a plane surface, bounded 
 by three right lines, I have both a true and 
 an adequate conception of it. [369] There 
 is nothing belonging to a plane triangle 
 which is not comprehended in this conception 
 of it, or deducible from it by just reasoning. 
 This definition expresses the whole essence 
 of the thing defined, as every just definition 
 ought to do ; but this essence is only what 
 Mr Locke very properly calls a nominal 
 essence ; it is a general conception formed 
 by the mind, and joined to a general word 
 as its sign. 
 
 If all the general words of a language had 
 a precise meaning, and were perfectly un- 
 derstood, as mathematical terms are, all 
 verbal disputes would be at an end, and 
 men would never seem to differ in opinion, 
 but when they differ in reality; but this is 
 far from being the case. The meaning of 
 most general words is not learned, like that 
 of mathematical terms, by an accurate 
 definition, but by the experience we happen 
 to have, by hearing them used in conversa- 
 tion. From such experience, we collect 
 their meaning by a kind of induction ; and, 
 as this induction is, for the most part, lame 
 and imperfect, it happens that different per- 
 sons join different conceptions to the same 
 general word ; and, though we intend to 
 give them the meaning which use, the 
 arbiter of language, has put upon them, 
 this is difficult to find, and apt to be mis- 
 taken, even by the candid and attentive. 
 Hence, in innumerable disputes, men do not 
 really difJ'er in their judgments, but in the 
 way of expressing them. 
 
 Our conceptions, therefore, appear to be 
 of ihiee kinds. They arc either the concep- 
 tions of individual things, the creatures of 
 God ; or they are conceptions of tlio mean- 
 ing of general words ; or they are the crea- 
 tures of our own imagination : and these 
 different kinds have different properties, 
 which we have endeavoured to describe, 
 
 3. Our conception of things may b(! strong 
 and lively, or it may be faint and languid in 
 all degrees. These are qualities which pro- 
 perly belong to our conceptions, thoUf;li we 
 have no names for them but such as arc; 
 analogical. Every man is conscious of such 
 a difference in his conceptions, and finds his 
 lively conceptions most agreeable, when the 
 ohtject is not of such a nature as to give 
 pain. VMO] 
 
 Tliosf; who have lively conceptions, com- 
 monly express them in a lively manner — 
 that is, in such a manner as to raise lively 
 conceptions and emotions in others- Sucii 
 persons are the most agreeable companions 
 [369-371 J 
 
 in conversation, and the most acceptable in 
 their writings. 
 
 The liveliness of our conceptions proceeds 
 from difierent causes- Some objects, from 
 their own nature, or from accidental aseo- 
 ciations, are apt to raise strong emotions in 
 the mind, Joy and hope, ambition, zeal, 
 and resentment, tend to enliven our con- 
 ceptions ; disappointment, disgrace, grief, 
 and envy, tend rather to flatten them. Men 
 of keen passions are commonly lively and 
 agreeable in conversation ; and dispassion- 
 ate men often make dull companions. There 
 is in some men a natural strengtluand vigour 
 of mind which gives strength to their con- 
 ceptions on all subjects, and in all the occa- 
 sional variations of temper. 
 
 It seems easier to form a lively concep- 
 tion of objects that are fiimiliar, than of 
 those that are not ; our conceptions of visible 
 objects are commonly the most lively, when 
 other circumstances are equal. Hence. 
 poets not only delight in the description of 
 visible objects, but find means, by meta- 
 phor, analogy, and allusion, to clothe every 
 object they describe with visible qualities. 
 The lively conception of these makes the 
 object appear, as it were, before our eyes. 
 Lord Kames, in his Elements of Criticism, 
 has shewn of what importance it is in 
 works of taste, to give to objects described, 
 what he calls ideal presence* To produce 
 this in the mind, is, indeed, the capital aim 
 of poetical and rhetorical description. It 
 carries the man, as it were, out of himself, 
 and makes him a spectator of the scene 
 described. This ideal presence seems to me, 
 to be nothing else but a lively conception of 
 the appearance which the object would make 
 if really present to the eye. [371 ] 
 
 Abstract and general conceptions are 
 never lively, though they may be distinct ; 
 and, therefore, however necessary in jiliilo- 
 sophy, seldom enter into poetical descrip- 
 tion without being particularised or clothed 
 in some visible dress. -f- 
 
 It may be observed, however, that our 
 conceptions of visible objects becume more 
 lively by giving them motion, ami more 
 still by giving them life and intellectual 
 qualities. Hence, in poetry, the whole crea- 
 tion is animated, and endowed with sense 
 and reflection. 
 
 Imagination, when it is distinguished 
 from conception, seems to me to signify 
 one species of conception —to wit, tiie con- 
 
 * The 'Eva{yi/«, "TTOrCTvnt, '1'xtrarr!«, O^ic, 
 EliuXoreilx, VisioiKS, of the aiiLiCIlt lthrUiiici:iiis. — 
 H. 
 
 t They thus cpa«e to bo aiiRhtd/wOvir/ nuA (ii-tu-riit , 
 and become merely Imlivulual riiirchciiiiiiinTis. In 
 precine lanKiiiiKii 'hey are no loiiK<'r ,or.u.fri, hut 
 <f(t.i,i(x.irfjuii.T» ; no longer Utvrill''', hm An.iiiiuiiiiniicn ; 
 no longer mitiiinx or i-iitirr/itx, liiit immji-s. I hcwor 1 
 " jiitrltciititritcd" ought to have beeai iiuliviiiiuiliiid 
 — II.
 
 3G6 
 
 ON THE INTELLECTUAL POWERS. 
 
 [essay IV. 
 
 ception of visible objects.* Thus, in a 
 mathematical proposition, I imagine the 
 figure, and I conceive the demonstration ; 
 it would not, I think, be improper to say, 
 I conceive both ; but it would not be so 
 proper to say, I imagine the demonstration. 
 6. Our conceptions of things may be clear, 
 distinct, and steady ; or they may be ob- 
 scure, indistinct, and wavering. The live- 
 liness of our conceptions gives pleasure, 
 but it is their distinctness and steadiness 
 that enables us to judge right, and to 
 express our sentiments with perspicuity. 
 
 If we inquire into the cause, why, among 
 persons speaking or writing on the same 
 subject, we find in one so much darkness, 
 in another so much perspicuity, I believe 
 the chief cause will be found to be, that 
 one had a distinct and steady concep- 
 tion of what he said and wrote, and the 
 other had not. Men generally find means 
 to express distinctly what they have con- 
 ceived distinctly. Horace observes, that 
 proper words spontaneously follow distinct 
 conceptions — " Verbaque provisam rem non 
 invita sequuntur." But it is impossible 
 that a man should distinctly express what 
 he has not distinctly conceived. [372] 
 
 We are commonly taught that perspicuity 
 depends upon a proper choice of words, a 
 proper structure of sentences, and a proper 
 order in the whole composition. All this 
 is very true ; but it supposes distinctness in 
 our conceptions, without which there can 
 be neither propriety in our words, nor in 
 the structure of our sentences, nor in our 
 method. 
 
 Nay, 1 apprehend that indistinct con- 
 ceptions of things are, for the most part, 
 the cause, not only of obscurity in writing 
 and speaking, but of error in judging. 
 
 Must not they who conceive things in the 
 same manner form the same judgment of 
 their agreements and disagreements ? Is 
 it possible for two persons to differ with 
 regard to the conclusion of a syllogism who 
 have the same conception of the premises ? 
 Some persons find it difficult to enter 
 into a mathematical demonstration. I be- 
 lieve we shall always find the reason to be, 
 that they do not distinctly apprehend it. 
 A man cannot be convinced by what he 
 does not understand. On the other hand, 
 I think a man cannot understand a de- 
 monstration without seeing the force of it. 
 I speak of such demonstrations as those 
 of Euclid, where every step is set down, and 
 nothing left to be supplied by the reader. 
 
 * It is to be regretted that Reid did not more fully 
 develope ihe dislinction of Imagination and Concep- 
 lion, on which he here and elsewhere inadequately 
 touches. Imagination is not, though in cinfnrmity 
 to the etvmolngy of the term, to be limited to the 
 representation of visible objects. See below, under 
 p. 4S2. Neither ought the term conceive to be u-ied 
 in Ihe extensive sense of understand H. 
 
 Sometimes one who has got through the 
 first four books of Euchd's " Elements " 
 and sees the force of the demonstrations, 
 finds difficulty in the fifth. What is the 
 reason of this ? You may find, by a httle 
 conversation with him, that he has not a 
 clear and steady conception of ratios, and 
 of the terms relating to them. When the 
 terms used in the fifth book have become 
 familiar, and readily excite in his mind a 
 clear and steady conception of their mean- 
 ing, you may venture to affirm that he will 
 be able to understand the demonstrations 
 of that book, and to see the force of them. 
 [373] 
 
 If this be really the case, as it seems to 
 be, it leads us to think that men are very 
 much upon a level with regard to mere 
 judgment, when we take that faculty apart 
 from the apprehension or conception of the 
 things about which we judge; so that a 
 sound judgment seems to be the inseparable 
 companion of a clear and steady apprehen- 
 sion. And we ought not to consider these 
 two as talents, of which the one may fall to 
 the lot of one man, and the other to the lot 
 of another, but as talents which always go 
 together. 
 
 It may, however, be observed, that some 
 of our conceptions may be more subservient 
 to reasoning than others which are equally 
 clear and distinct. It was before observed, 
 that some of our conceptions are of indi- 
 vidual things, others of things general and 
 abstract. It may happen that a man who 
 has very clear conceptions of things in- 
 dividually, is not so happy in those of 
 things general and abstract. And this I 
 take to be the reason why we find men 
 who have good judgment in matters of 
 common life, and perhaps good talents for 
 poetical or rhetorical composition, who find 
 it very difficult to enter into abstract reas- 
 oning. 
 
 That I may not appear singular in put- 
 ting men so much upon a level in point of 
 mere judgment, I beg leave to support this 
 opinion by the authority of two very think 
 ing men, Des Cartes and Cicero. The 
 former, in his dissertation on Method, ex- 
 presses himself to this purpose: — " Nothing 
 is so equally distributed among men as 
 judgment. " Wherefore, it seems reasonable 
 to believe, that the power of distinguishing 
 what is true from what is false, (which we 
 properly call judgment or right reason,) is 
 by nature equal in all men ; and therefore 
 that the diversity of our opinions does not 
 arise from one person being endowed with 
 a greater power of reason than another, but 
 only from this, that we do not lead our 
 
 * " Judgment," bona mens, in the authentic 
 Latin translation. I cannot, at the moment, lay 
 hands on my copy of the French original j but, if I 
 recollect aright, it is there le bon sens H. 
 
 r372,373]
 
 CHAP. 1.] OF SIMPLE APPREHENSION IN GENERAL. 
 
 3G7 
 
 thought in the same track, nor attend to 
 the same things." 
 
 Cicero, in his third book'" De Oratore," 
 makes this observation — " It is wonderful 
 when the learned and unlearned differ so 
 much in art, how little they differ in judg- 
 ment. For art being derived from Nature, 
 is good for nothing, unless it move and 
 delight Nature." [374] 
 
 From what has been said in this article, 
 it follows, that it is so far in our power to 
 write and speak perspicuously, and to reason 
 justly, as it is in our power to form clear 
 and distinct conceptions of the subject on 
 which we speak or reason. And, though 
 Nature hath put a wide difference between 
 cue man and another in this respect, yet 
 that it is in a very considerable degree in 
 our power to have clear and distuict appre- 
 hensions of things about which we think 
 and reason, cannot be doubted. 
 
 7. It has been observed by many authors, 
 that, when we barely conceive any object, 
 the ingredients of that conception must 
 either be things with which we were before 
 acquainted by some other original power of 
 the mind, or they must be parts or attri- 
 butes of such things. Thus, a man cannot 
 conceive colours if he never saw, nor sounds 
 if he never heard. If a man had not a con- 
 science, he could not conceive what is meant 
 by moral obligation, or by right and wrong 
 in conduct. 
 
 Fancy may combine things that never 
 were combined in reality. It may enlarge 
 or diminish, multiply or divide, compound 
 arid fashion the objects which nature pre- 
 sents ; but it cannot, by the utmost effort 
 of that creative power which we ascribe to 
 it, bring any one simple ingredient into its 
 productions which Nature has not framed 
 and brought to our knowledge by some 
 other faculty. 
 
 This Mr Locke has expressed as beauti- 
 fully as justly. The dominion of man, in 
 this little world of his own understanding, 
 is much the same as in the great world of 
 visible things ; wherein his power, however 
 managed by art and skill, reaches no farther 
 than to compound and divide the materials 
 that are made to his hand, but can do no- 
 thing towards making the least particle of 
 matter, or destroying one atom that is 
 already in being. [375] The same inability 
 will every one find in himself, to fashion in his 
 understanding any simj)le idea not received 
 by the powers which (Jod has given him. 
 
 I think ail jiliilosophers agree in this senti- 
 ment. Mr Ilimie, indeed, after acknow- 
 ledging the truth of the principle in general, 
 mentions what he thinks a single exception 
 to it — That a man, who had seen all the 
 shades of a particniar colour except one, 
 might frame in his mind a concc[)tion of 
 that shade which he never saw. I think 
 [374-37fij 
 
 this is not an exception ; because a parti- 
 cular shade of a colour differs not specifically, 
 but only in degree, from other shades of the 
 same colour. 
 
 It is proper to observe, that our most 
 simple conceptions are not those which 
 nature immediately presents to us. When 
 we come to years of understanding, we have 
 the power of analysing the objects of nature, 
 of distinguishing their several attributes 
 and relations, of conceiving them one by 
 one, and of giving a name to each, whose 
 meaning extends only to that single attri- 
 bute or relation : and thus our most simple 
 conceptions are not those of any object in 
 nature, but of some single attribute or rela- 
 tion of such objects. 
 
 Thus, nature presents to our senses 
 bodies that are extended in three dimensions, 
 and solid. By analysing tlie notion we have 
 of body from our senses, we form to our- 
 selves the conceptions of extension, solidity, 
 space, a point, a line, a surface — all which 
 are more simple conceptions than that of a 
 body. But they are the elements, as it 
 were, of which our conception of a body is 
 made up, and into which it may be analysed. 
 This power of analysing objects we propose 
 to consider particularly in another place. 
 It is only mentioned here, that what is said 
 in this article may not be understood so as 
 to be inconsistent with it. [376] 
 
 8. Though our conceptions must be con- 
 fined to the ingredients mentioned in the 
 last article, we are unconfined with regard 
 to the arrangement of those ingredients. 
 Here we may pick and choose, and form 
 an endless variety of combinations and com- 
 positions, which we call creatures of the 
 imagination. These may be clearly con- 
 ceived, though they never existed : and, 
 indeed, everything that is made, must have 
 been conceived before it was made. Every 
 work of human art, and every plan of con- 
 duct, whether in public or in private life, 
 must have been conceived before it was 
 brought to execution. And we cannot avoid 
 thinking, that the Almighty, before he 
 created the universe by his power, had a 
 distinct conception of the whole and of every 
 part, and saw it to be good, and agreeable 
 to his intention. 
 
 It is the business of man, as a rational 
 creature, to employ this unlimited jiower of 
 conception, for ])lanning his conduct and 
 enlarging his knowledge. It seems to be 
 j)eculiar to beings endowed with reason to 
 act by a preconceived plan. Brute animals 
 seem either to want this power, or to liavo 
 it in a very low degree. They are moved 
 by instinct, habit, a])])«tite, or natural affec- 
 tion, according a.s these principles are stirred 
 by the present occasion. JSut I see no 
 reason to think that they can projiosu lo 
 tiiemselves a connected plan of life, or form
 
 36n 
 
 ON THE INTELLECTUAL POWERS. 
 
 [essay IV. 
 
 general rules of conduct Indeed, we see 
 that many of the human species, to whom 
 God has given this power, make little use 
 of it. They act without a plan, as the pas- 
 sion or appetite which is strongest at the 
 time leads them. 
 
 9. The last property I shall mention of 
 thie faculty, is that which essentially dis- 
 tinguishes it from every other power of the 
 mind ; and it is, that it is not employed 
 solely about things which have existence. 
 I can conceive a winged horse or a centaur, 
 as easily and as distinctly as I can conceive 
 a man whom I have seen- Nor does this 
 distinct conception incline my judgment in 
 the least to the belief that a winged horse 
 or a centaur ever existed. [377] 
 
 It is not so with the other operations of 
 our minds. They are employed about real 
 existences, and carry with them the belief 
 of their objects. When I feel pain, I am 
 compelled to believe that the pain that I 
 feel has a real existence. When I perceive 
 any external object, my belief of the real 
 existence of the object is irresistible. When 
 I distinctly remember any event, though 
 that event may not now exist, I can have 
 no doubt but it did exist. That conscious- 
 ness which we have of the operations of 
 our own minds, implies a belief of the real 
 existence of those operations. 
 
 Thus we see, that the powers of sensa- 
 tion, of perception, of memory, and of con- 
 sciousness, are all employed solely about 
 objects that do exist, or have existed. But 
 conception is often employed about objects 
 that neither do, nor did, nor will exist. This 
 is the very nature of this faculty, that its 
 object, though distinctly conceived, may 
 have no existence. Such an object we call 
 a creature of imagination ; but this creature 
 never was created. 
 
 That we may not impose upon ourselves 
 in this matter, we must distinguish between 
 that act or operation of the mind, which we 
 call conceiving an object, and the object 
 which we conceive. When we conceive 
 anything, there is a real act or operation of 
 the mind. Of this we are conscious, and 
 can have no doubt of its existence. But 
 every such act must have an object ;* for he 
 that conceives must conceive sonietliing. 
 Suppose he conceives a centaur, he may 
 have a distinct conception of this object, 
 though no centaur ever existed. 
 
 I am afraid that, to those who are unac- 
 quainted with the doctrine of philosophers 
 upon this subject, I shall appear in a very 
 ridiculous light, for insisting upon a point 
 so very evident as that men may barely 
 conceive things that never existed. They 
 will hardly believe that any man in his wits 
 «ver doubted of it. Indeed, I know no 
 
 * See belciw, j). 390, and Note B.— H. 
 
 truth more evident to the common sense and 
 to the experience of mankind. But, if the 
 authority of philosophy, ancient and modern, 
 opposes it, as I think it does, I wish not" 
 to treat that authority so fastidiously as not 
 to attend patiently to what may be said in 
 support of it. [378] 
 
 CHAPTER IL 
 
 THEORIES CONCERNING CONCEPTION. 
 
 The theory of ideas has been applied to 
 the conception of objects, as well as to per- 
 ception and memory. Perhaps it will be 
 irksome to the reader, as it is to the writer, 
 to rettirn to that subject, after so much has 
 been said upon it ; but its application to the 
 conception of objects, which could not pro- 
 perly have been introduced before, gives a 
 more comprehensive view of it, and of the 
 prejudices which have led philosophers so 
 unanimously into it. 
 
 There are two prejudices which seem to 
 me to have given rise to the theory of ideas 
 in all the various forms in which it has ap- 
 peared in the course of above two thousand 
 years ; and, thounh they have no support 
 from the natural dictates of our faculties, 
 or from attentive reflection upon their oper- 
 ations, they are prejudices which those who 
 speculate upon this subject are very apt to 
 be led into by analogy. 
 
 The first is — That, in all the operations of 
 the understanding, there nmst be some im- 
 mediate intercourse between the mind and 
 its object, so that the one may act upon the 
 other. The second. That, in all the opera- 
 tions of understanding, there must be an 
 object of thought, which really exists while 
 we think of it ; or, as some philosophers 
 have expressed it, that which is not cannot 
 be intelligible. 
 
 Had philosophers perceived that these are 
 prejudices grounded only upon analogical 
 reasoning, we had never heard of ideas in 
 the philosophical sense of that word. [379] 
 
 The^r*^ of these principles has led philo- 
 sophers to think that, as the external 
 objects of sense are too remote to act upon 
 the mind immediately, there must be some 
 image or shadow of them that is present to 
 the mind, and is the immediate object of 
 perception. That there is such an imme- 
 diate object of perception, distinct from 
 the external object, has been very unani- 
 mously held by philosophers, though they 
 have differed much about the name, the 
 
 * The reader will bear in mind what has been 
 already said of the limited meaning attached by 
 Reid to the term Idea, viz., somelhinp in, or present 
 to the mind, but not a mere modification of the 
 mind — and his error in supposing ihai all philosophers 
 admitKd this crude hypothesis. See Notes B, C, L, 
 M, N, O, P, iic— H. 
 
 [377-3791
 
 CtlAP, 
 
 .1.] 
 
 THEORIES CONCERNING CONCEPTION. 
 
 :i()<) 
 
 nature, and the origin of those immediate 
 objects. 
 
 We have cousidered wliat has been said in 
 the suppt)rt of this principle, Essay II. chap- 
 14, to which the reader is referred, to 
 prevent repetition. 
 
 I shall only add to what is there said, 
 That there appears no shadow of reason 
 why the mind must liave an object imme- 
 diately present to it in its intellectual oper- 
 ations, any more than in its aflections and 
 passions. Philosophers have not said that 
 ideas are the immediate objects of love or 
 resentment, of esteem or disapprobation. 
 It is, I think, acknowledged, that persons 
 and not ideas, are the immediate objects of 
 those affections ; persons, who are as far 
 from being immediately present to the mind 
 a.s other external objects, and, sometimes, 
 persons who have now no existence, in this 
 world at least, and wlio can neither act 
 upon the mind, nor be acted upon by it. 
 
 The second principle, which I conceive 
 to be likewise a prejudice of philosophers, 
 grounded upon analogy, is now to be 
 considered. 
 
 It contradicts directly what was laid down 
 in the last article of the preceding chapter 
 — to wit, that we may have a distinct con- 
 ception of things which never existed. This 
 is undoubtedly the common belief of those 
 who have not been instructed in philosoi)hy ; 
 and they will think it as ridiculous to defend 
 it by reasoning, as to oppose it. [380] 
 
 The philosopher says, Though there 
 may be a remote object which does not ex- 
 ist, there must be an immediate object 
 which really exists ; for that which is not, 
 Cannot be an object of thought. The idea 
 must be perceived by the mind, and, if it 
 does not exist there, there can be no per- 
 ception of it, no operation of the mind 
 about it.* 
 
 This principle deserves the more to be 
 examined, because the other before men- 
 tioned depends upon it ; for, althougli the 
 last may be true, even if the first was false, 
 yet, if the last be not true, neither can the 
 first. If we can conceive objects which 
 have no existence, it follows that there may 
 be objects of thought which neither act upon 
 the mind, nor are acted upon by it ; because 
 that which has no existence can neither act 
 nor be acted upon. 
 
 It is by these principles that philosoi)hers 
 have been led to think that, in every act of 
 memory and of conception, as well as of 
 perception, there are two objects — the 
 one, tlic immediate olijcct, the idea, the 
 species, the form ; tlie other, the mediate 
 or external object- The vulgar know on!} 
 
 * In rt'laiion to this and wha' follows, nee ahove, 
 p. 2iK, b, note t ; p. "^18, a, noti' \ ; anil Note H. 
 
 [380,3811 
 
 of one object, which, in perception, is some- 
 thing external that exists ; in memory, 
 something that did exist ; and, in concep- 
 tion, may be something that never existed.* 
 But the innnediate object of the philo- 
 sophers, the idea, is said to exist, and to be 
 perceived in all these operations. 
 
 These principles have not only led philo- 
 sophers to split olijects into two, where 
 others can find but one, but likewise have 
 led them to reduce the three operations now 
 mentioned to one, making memory and con- 
 ception, as well as perception, to be the per- 
 ception of ideas. But nothing appears more 
 evident to the vulgar, than that what is 
 only remembered, or only conceived, is not 
 perceived ; and, to speak of the perceptions 
 of memory, appears to them as absurd as 
 to speak of the hearing of sight. [381 ] 
 
 In a word, these two principles carry us 
 into the whole philosophical theory of ideas, 
 and furnish every argument that ever was 
 used for their existence. If they are true, 
 that system must be admitted with all its 
 consequences. If they are only prejudices, 
 grounded upon analogical reasoning, the 
 whole system must fall to the ground with 
 them. 
 
 It Ls, therefore, of importance to trace 
 those principles, as far as we are able, to 
 their origin, and to see, if possible, whether 
 they have any just foundation in reason, or 
 whether they are rash conclusions, drawn 
 from a supposed analogy between matter 
 and mind. 
 
 The unlearned, who are guided by the 
 dictates of nature, and express what they 
 are conscious of concerning the operations 
 of their own mind, believe that the object 
 which they distinctly perceive certainly 
 exists ; that the object which they distinctly 
 remember certainly did exist, but now may 
 not ; but as to things that are barely con- 
 ceived, they know that they can conceive a 
 thousand things that never existed, and that 
 the bare conception of a thing does not so 
 much as attbrd a presumption of its exist- 
 ence. They give themselves no trouble to 
 know how these operations are performed, or 
 to account for them from general principles. 
 
 But philosophers, who wish to discover 
 the causes of things, and to accoimt for 
 these operations of mind, ob.serving that in 
 other operations there must be not only an 
 agent, but somctiiing to act upon, have 
 been led by analogy to conclude that it 
 must be so in the operations of the mind. 
 
 'J'lie relation between the mind and its 
 conceptions bears a very strong and obvious 
 analogy to the relation between a man ami 
 iiis work. Every scheme he forms, every 
 discovery he makes Ijy ids reasoning power.-, 
 is very properly called the work of hi.s mind. 
 Tiie.se works of tlie mind are soinetiutoti 
 * Sei' rcfi'icim-i in jTrrtillrii- iioir. — II. 
 
 U U
 
 370 
 
 ON THE INTELLECTUAL POWERS. 
 
 [essay jv. 
 
 great and important works, and draw the 
 attention and admiration of men. [382] 
 
 It is the provuice of the philosopher to 
 consider how such works of the mind are 
 produced, and of what materials they are 
 composed. He calls the materials ideas. 
 There must therefore be ideas, which the 
 mind can arrange and form, into a regular 
 structure. Everything that is produced, 
 must be produced of something ; and from 
 nothing, nothing can be produced. 
 
 Some such reasoning as this seems to me 
 to have given the first rise to the philoso- 
 phical notions of ideas. Those notions were 
 formed into a system by the Pythagoreans, 
 two thousand years ago ; and this system 
 was adopted by Plato, and embellished with 
 all the powers of a fine and lofty imagina- 
 tion. I shall, in compliance with custom, 
 call it the Platonic system of ideas, though 
 in reality it was the invention of the Pytha- 
 gorean school.' 
 
 The most arduous question which em- 
 ployed the wits of men in the infancy of 
 the Grecian philosophy was — What was the 
 origin of the world ? — from what principles 
 and causes did it proceed ? To this ques- 
 tion very different answers were given in 
 the different schools. Most of them appear 
 to us very ridiculous. The Pythagoreans, 
 however, judged, very rationally, from the 
 order and beauty of the universe, that it 
 must be the workmanship of an eternal, in- 
 telligent, and good being : and therefore 
 they concluded the Deity to be one first 
 principle or cause of the universe. 
 
 But they conceived there must be more. 
 The universe must be made of something. 
 Every workman must have materials to 
 work upon. That the world should be made 
 out of nothing seemed to them absurd, be- 
 cause everything that is made must be made 
 of something. 
 
 Nullam rem e nihilo gigni divinitus unquam. — LucR. 
 De tiibilo nihil, in nihilum nil posse reverti. — Peks. 
 
 This maxim never was brought into doubt : 
 even in Cicero's time it continued to be 
 held by all philosophers. [383] What 
 natural philosopher (says that author in his 
 second book of Divination) ever asserted 
 that anything could take its rise from 
 nothing, or be reduced to nothing ? Be- 
 cause men must have materials to work 
 upon, they concluded it must be so with 
 the Deity. This was reasoning from analogy. 
 From this it followed, that an eternal 
 uncreated matter was another first prin- 
 ciple of the universe. But this matter they 
 believed had no form nor quality. It was 
 
 * Ideas in the Platonic, and Ideas in the modern 
 signification, hold, as I hare already shewn, little 
 or no analogy to each other. See al>ovc, p. 204, a, 
 notes + t ; P- 225, b, note * j p. 26'^, b note *,— H. 
 
 the same with the materia prima or first 
 matter of Aristotle, who borrowed this part 
 of his philosophy from his predecessors. 
 
 To us it seems more rational to think 
 that the Deity created matter with its qua- 
 lities, than that the matter of the universe 
 should be eternal and self-existent. But 
 so strong was the prejudice of the ancient 
 philosophers against what we call creation, 
 that they rather chose to have recourse to 
 this eternal and unintelligible matter, that 
 the Deity might have materials to work 
 upon. 
 
 The same analogy which led them to 
 think that there must be an eternal matter of 
 which the world was made, led them also 
 to conclude that there must be an eternal 
 pattern or model according to which it was 
 made. Works of design and art must be 
 distinctly conceived before they are made. 
 The Deity, as an intelligent Being, about 
 to execute a work of perfect beauty and 
 regularity, must have had a distinct con- 
 ception of his work before it was made. 
 This appears very rational. 
 
 But this conception, being the work of 
 the Divine intellect, something must have 
 existed as its object. This could only be 
 ideas, which are the proper and immediate 
 object of intellect. [384] 
 
 From this investigation of the principles 
 or causes of the universe, those philoso- 
 phers concluded them to be three in number 
 — to wit, an eternal matter as the material 
 cause, eternal ideas as the model or exem- 
 plary cause, and an eternal intelligent mind 
 as the efficient cause. 
 
 As to the nature of those eternal ideas, 
 the philosophers of that sect ascribed to 
 them the most magnificent attributes. 
 They were immutable and uncreated ;* the 
 object of the Divine intellect before the 
 world was made ; and the only object of 
 intellect and of science to all intelligent 
 beings. As far as intellect is superior to 
 sense, so far are ideas superior to all the 
 objects of sense. The objects of sense 
 being in a constant flux, cannot properly 
 be said to exist. Ideas are the things 
 which have a real and permanent exist- 
 ence. They are as various as the species of 
 things, there being one idea of every spe- 
 cies, but none of individuals. The idea is 
 the essence of the species, and existed be- 
 fore any of the species was made. It is 
 entire in every individual of the species, 
 without being either divided or multiplied. 
 
 In our present state, we have but an 
 imperfect conception of the eternal ideas ; 
 but it is the highest felicity and perfection 
 of men to be able to contemplate them. 
 
 * Whether, in the Platonic system. Ideas are, or 
 are not, independent of the Deity, I have already 
 stated, is, and always has been, a vexata qiurstw.— 
 H. 
 
 [382-384.]
 
 CHAP. ii.J THEORIES CONCERNING CONCEPTION. 
 
 371 
 
 While we are in this prison of the body, 
 sense, as a dead weight, bears us down 
 from the contemplation of the intellectual 
 objects ; and it is only by a due purifica- 
 tion of the soul, and abstraction from sense, 
 that the intellectual eye is opened, and that 
 we are enabled to mount upon the wings of 
 uitellect to the celestial world of ideas. 
 
 Such was the most ancient system con- 
 cerning ideas, of which we have any account. 
 And, however different from the modern, 
 it appears to be built upon the prejudices 
 we have mentioned — to wit, that in every 
 operation there must be something to work 
 upon ; and that even in conception there 
 must be an object which really exists. 
 [385] 
 
 For, if those ancient philosophers had 
 thought it possible that the Deity could 
 operate without materials in the formation 
 of the world, and that he could conceive 
 the plan of it without a model, they could 
 have seen no reason to make matter and 
 ideas eternal and necessarily existent prin- 
 ciples, as well as the Deity himself. 
 
 whether they believed that the ideas 
 were not only eternal, but eternally, and 
 without a cause, arranged in that beautiful 
 and perfect order which they ascribe to this 
 intelligible world of ideas, I cannot say ; 
 but this seems to be a necessary conse- 
 quence of the system : for, if the Deity 
 could not conceive the plan of the world 
 which he made, without a model which 
 really existed, that model could not be his 
 work, nor contrived by his wisdom ; for, if 
 he made it, he must have conceived it 
 before it was made ; it must therefore have 
 existed in all its beauty and order inde- 
 pendent of the Deity ; and this I think 
 they acknowledged, by making the model 
 and the matter of this world, first princi- 
 ples, no loss than the Deity. 
 
 If the Platonic .system be thus understood, 
 (and I do not see how it can hang together 
 otherwise,) it leads to two consequences 
 that are unfavourable to it. 
 
 First, Nothing is left to the Maker of 
 this world but the skill to work after a 
 model. The model had all the perfection 
 and beauty that appears in the cojjy, and 
 the Deity had only to copy after a jiattern 
 that existed independent of him. Indeed, 
 the copy, if we believe those philosophers, 
 falls very far short of the original ; but this 
 they seem to have ascribed to the refracto- 
 riness of matter of which it was made. 
 
 Secondh/, If the world of ideas, without 
 being the work of a perfectly wise and good 
 iiit(;lligent being, could have so much beauty 
 and perfection, iiow can we infer from the 
 beauty and order of this world, wliich is 
 but an imperfect copy of the other, that it 
 must liave been n)ade by a perfectly wise 
 and good being ? (lUKj] Tiu! force of this 
 J 38.5-.'i87 ] 
 
 reasoning, from the beauty and order of the 
 universe, to its being the work of a wise 
 being, which ap|;ears invincible to every 
 candid mind, and appeared so to those 
 ancient philosophers, is entirely destroyed 
 by the supposition of the existence of a 
 world of ideas, of greater perfection and 
 beauty, \\hich never was made. Or, if the 
 reasoning be good, it will apjily to the world 
 of ideas, which must, of consequence, have 
 been made by a wise and good intelligent 
 being, and must have been conceived before 
 it was made. 
 
 It may farther be observed, that all that 
 is mysterious and unintelligible in the Pla- 
 tonic ideas, arises from attributing existence 
 to them. Take away this one attribute, all 
 the rest, however pompously expressed, 
 are easily admitted and understood. 
 
 What is a Platonic idea ? It is the 
 essence of a species. It is the exemplar, the 
 model, according to which all the individuals 
 of that species are made. It is entire in 
 every individual of the species, without be- 
 ing multiplied or divided. It was an object 
 of the divine intellect from eternity, and is an 
 object of contemplation and of science to 
 every intelligent being. It is etei-nal, im- 
 mutable, and uncreated ; and, to crown all, 
 it not only exists, but has a more real and 
 permanent existence than anything that 
 ever God made. 
 
 Take this description altogether, and it 
 would require an QSdipus to unriddle it. 
 But take away the last part of it, and no- 
 thing is more easy. It is easy to find five 
 hundred things which answer to every 
 article in the description except the last. 
 
 Take, for an instance, the nature of a 
 circle, as it is defined by Euclid— an object 
 which every intelligent being may conceive 
 distinctly, though no circle had ever existed; 
 it is the exemplar, tlie model, according to 
 which all the individual figures of that 
 species that ever existed were made ; for 
 they are all made according to the nature of a 
 circle. [387] It is entire in every individual 
 of the species, without being multiplied or 
 divided. For every circle is an entire 
 circle ; and all circles, in as far as they are 
 circles, have one and the same nature. It 
 was an oljject of the divine intellect from 
 all eternity, and nuiy be an object of con- 
 templation and of science to every intelli- 
 gent being. It is the essence of a species, 
 and, like all other essences, it is eternal, 
 imnmtable, and uncreated. This means 
 no more but that a circle always was a 
 circle, and can never be anything but a 
 circle. It is the necessity of the thing, 
 and not any act of creating power, that 
 makes a circle to be a circle. 
 
 'J'he nature of every species, whether of 
 substance, of (luality, or of relation, and in 
 genenil everything wliich tlio ancients railed 
 
 U 11 '^
 
 S72 
 
 ON THE INTELLECTUAL POWERS. 
 
 [kSSAY IV. 
 
 an universal, answers to the description of 
 a Platonic idea, if in that description you 
 leave out the attribute of existence. 
 
 If we believe that no species of things 
 could be conceived by the Almighty with- 
 out a model that really existed, we must go 
 back to the Platonic system, however mys- 
 terious. But, if it be true that the Deity 
 could have a distinct conception of things 
 which did not exist, and that other intelligent 
 beings may conceive objects which do not 
 e^List, the system has no better foundation 
 than this prejudice, that the operations of 
 mind must be like those of the body. 
 
 Aristotle rejected the ideas of liis mnster 
 Plato as visionary; but he retained the 
 prejudices that gave rise to them, and there- 
 fore substituted something in their place, 
 but under a different name,* and of a dif- 
 ferent origin. 
 
 He called the objects of intellect, intelli- 
 gible species ; those of the memory and 
 imagination, phantasms ; and those of the 
 senses, sensible species. This change of the 
 name* was indeed very small ; for the Greek 
 word of Aristotle [sfSof ] which we translate 
 species or form, is so near to the Greek 
 word idea, both in its sound and significa- 
 tion, that, from their etymology, it would 
 not be easy to give them diffei'ent meanings. 
 [388] Both are derived from the Greek word 
 which signifies to see, and both may signify a 
 vision or appearance to the eye. Cicero, who 
 understood Greek well, often translates the 
 Greek word ilea by the Latin word visio. 
 But both words being used as terms of art — 
 one in the Platonic system, the other in the 
 Peripatetic — the Latin writers generally 
 borrowed the Greek word idea to express the 
 Platonic notion, and translated Aristotle's 
 word, by the words species or forma ; and in 
 this they have been followed in the modern 
 languages. * 
 
 Those forms or species were called intelli- 
 gible, to distinguish them from sensible 
 species, which Aristotle held to be the imme- 
 diate objects of sense. 
 
 He thought that the sensible species come 
 from the external object, and defined a sense 
 to be that which has the capacity to receive 
 the form of sensible things without the mat- 
 ter ; as wax receives the form of a seal with- 
 out any of the matter of it. In like manner, 
 he thought that the intellect receives the 
 forms of things intelligible ; and he callsit 
 the place of forms. 
 
 * Reid seems not aware that Plato, and Aristotle 
 in relation to Plato, employed ttie terms iloo; and 
 iSia. almost as convertible. In fact, the latter usually 
 combats the ideal theory of the former by the name 
 of sfJoj — e. S-« Toi tiSv) x"^'?'-^") Tl^iriirf/.xra ya.^ £?■'■ 
 M. Cousin, in a learned and ingenious paper of his 
 " Noiiveaux Fragments," has endeavoured to shew 
 that I'lato did not apply the two terms indifferently; 
 and the- same has been attempted by Richter. But 
 so many exceptions must be admitted, that, api a- 
 rontly, no determinate rule can be established. — H. 
 
 I take it to have been the opinion of Aris- 
 totle, that the intelligible forms in the hu- 
 man intellect are derived from the sensible 
 by abstraction, and other operations of the 
 mind itself. As to the intelligible forms in 
 the divine intellect, they must have had 
 another origin ; but I do not rememljer that 
 he gives any opinion about them. He cer- 
 taiidy maintained, however, that there is no 
 intellection without intelligible species ;* 
 no memory or inuvgination without phan- 
 tasms ; no perception without sensible 
 species. Treating of memory, he proposes 
 a difficulty, and endeavours to resolve it — 
 how a phantasm, that is a present object in 
 the mind, should represent a thing that is 
 past. [389] 
 
 Thus, I think, it appears that the Per- 
 ipatetic system of species and phantasms, 
 as well as the Platonic system of ideas, is 
 grounded upon this principle, that in every 
 kind of thought there must be some object 
 that really exists ; in every operation of the 
 mind, something to work upon. Whether 
 this immediate object be called an idea with 
 Plato,-|- or a phantasm or species with Aris- 
 totle — whether it be eternal and uncreated, 
 or produced by the impressions of external 
 objects — is of no consequence in the pre- 
 sent argument. In both systems, it was 
 thought impossible that the Deity could 
 make the world without matter to work 
 upon ; in both, it was thought impossible 
 that an intelligent Being could conceive 
 anything that did not exist, but by means 
 of a model that really existed. 
 
 The philosophers of the Alexandrian 
 school, commonly called the latter Plato- 
 nists, conceived the eternal ideas of things 
 to be in the Divine intellect, and thereby 
 avoided the absurdity of making them a 
 principle distinct from and independent of 
 the Deity ; but still they held them to exist 
 really in the Divine mind as the objects of 
 conception, and as the patterns and arche- 
 types of things that are made. 
 
 Modern philosophers, still persuaded that 
 of every thought there must be an imme- 
 diate object that really exists, have not 
 deemed it necessary to distinguish by dif- 
 ferent names the immediate objects of in- 
 tellect, of imagination, and of the senses, 
 but have given the common name of idta 
 to them all. 
 
 Whether these ideas be in the sensorium, 
 or in the mind, or partly in the one and 
 partly in the other; whether they exist 
 when they are not perceived, or only when 
 
 * There is ,even less reason to attribute such a 
 theory to Aristotle in relation to the intellect than 
 in relation to sense and imagination. See even his 
 oldest commentator, the Aphrodi-ian, ni^}'^tjxr,s , 
 f. I:i9, a. In fact, the greater number of those Peri, 
 patetics who admitted species in thi? irude form for 
 the latter, rejected I hem for the former. — H. 
 
 \ See ahove, p. 26!, b, note *. — M. 
 
 f388, 3S9l
 
 CH 
 
 AF. II.] 
 
 THEORIES CONCERNING CONCEPTION. 
 
 373 
 
 they are perceived ; wlietlier they are the 
 workmanship of the Deity or of the mind 
 itself, or of external natural causes — with 
 regard to these points, different authors 
 seem to have different opinions, and the 
 same author sometimes to waver or l)e 
 diflSdent ; but as to their existence, there 
 seems to be great unanimity.* [390] 
 
 So much is this opinion fixed in the 
 minds of philosophers, that I doubt not but 
 it will appear to most a very strange para- 
 dox, or rather a contradiction, that men 
 should think without ideas- 
 
 That it has the appearance of a contra- 
 diction, I confess. But tliis appearance 
 arises from the ambiguity of the word idea. 
 If the idea of a thingraeans only the thought 
 of it, or the operation of the mind in think- 
 ing about it, which is the most common 
 meaning of the word, to think without ideas, 
 is to think without thought, which is un- 
 doubtedly a contradiction. 
 
 But an idea, according to the definition 
 given of it by philosophers, is not thought, 
 but an object of thought, which really exists 
 and is perceived. Now, whether is it a 
 contradiction to say, that a man may think 
 of an object that does not exist ? 
 
 I acknowledge that a man cannot per- 
 ceive an object that does not exist ; nor can 
 he remember an object that did not exist ; 
 but there appears to me no contradiction in 
 his conceiving an object that neither does 
 nor ever did exist. 
 
 Let us take an example. I conceive a 
 centaur. This conception is an operation 
 of the mind, of which I am conscious, and 
 to which I can attend. The sole object of it 
 is a centaur, an animal which, I believe, 
 never existed. I can see no contradiction 
 in this.-f 
 
 The philosopher says, I cannot conceive 
 a centaur without having an idea of it in 
 my mind. I am at a loss to understand 
 what he means. lie surely does not mean 
 that I cannot conceive it without conceiving 
 it. This would make me no wiser. What 
 then is this idea ? Is it an animal, half 
 horse and half man ? No. Then I am 
 certain it is not the thing I conceive. Per- 
 haps he will say, that the ideals an image 
 of the animal, and is the immediate object 
 of my conception, and that tlie iuiimal is 
 the mediate or remote object. J ['M\ ] 
 
 To this I answer — First, I am certain 
 there are not two objects of this conception, 
 but one only ; and that one is as immediate 
 an object of my conception as any can be. 
 
 SfcomUy, This one object which I c(jn- 
 ceive, is not the image of an animal — it is 
 
 * Thi«, as already once and again staled, i» not 
 correct. — II. 
 
 t See al)Ovc, p. W>, b, note t, and Note B.— II. 
 
 t On this, and the iiub«ef|iieMt reasoning in the 
 present eha|>ter, t.ee Note B. — II. 
 
 an animal. I know what it is to conceive 
 an image of an animal, and what it is to 
 conceive an animal ; and I can distinguish 
 the one of these from the other without 
 any danger of mistake. The thing I con- 
 ceive is a body of a certain figure and 
 colour, having life and spontaneous motion. 
 The philosopher says, that the idea is an 
 image of the animal ; but that it has neither 
 body, nor colour, nor life, nor spontaneous 
 motion. This I am not able to comprehend. 
 
 Thirdly, I wish to know how this idea 
 comes to be an object of my thought, when 
 I cannot even conceive what it means ; 
 and, if I did conceive it, this would be no 
 evidence of its existence, any more than 
 my conception of a centaur is of its exist- 
 ence. Philosophers sometimes say tliat we 
 perceive ideas, sometimes that we are con- 
 scious of them. I can have no doubt of 
 tlie existence of anything which I either 
 perceive or of which I am conscious ;• but 
 I cannot find that I either perceive ideas 
 or am conscious of them. 
 
 Perception and consciousness are very 
 different operations, and it is strange that 
 philosophers have never determined by 
 which of them ideas are discerned- -f- This 
 is as if a man should positively affirm that 
 he perceived an object ; but whether by his 
 eyes, or his ears, or his touch, he could not 
 say. 
 
 But may not a man who conceives a 
 centaur say, that he has a distinct image of 
 it in his mind ? I think he may. And if he 
 means by this way of speaking what the 
 vulgar mean, who never heard of the phi- 
 losophical theory of ideas, I find no fault 
 with it. [392] By a distinct image in the 
 mind, the vulgar mean a distinct concep- 
 tion ; and it is natural to call it so, on 
 account of the analogy between an image of 
 a thing and the conception of it. On ac- 
 count of this analogy, obvious to all man- 
 kind, this operation is called imagination, 
 and an image in the mind is only a peri- 
 phrasis for imagination. But to infer from 
 this that there is really an image in the 
 mind, distinct from the operation of con- 
 ceiving the object, is to be misled by an 
 analogical expression ; as if, from the 
 phrases of deliberating and balancing things 
 in the mind, we should infer that there is 
 really a balance existing in the mind for 
 weighing motives and arguments. 
 
 The analogical words and phrases used 
 in all languages to exjiress conci'i)tion, do, 
 no doubt, facilitate their being taken in a 
 literal sense. lUit, if we only attend carc- 
 
 * This is not the case, unless it be admitted that 
 we are conscious ol what wcpereeive— in other words, 
 iniinediiitely eon'iit'^'' "I'the ixm.Kjn.—W. 
 
 t lint the philosophers did not, \\V.v Hdd, make 
 Conscioustiess one speciul lacnlty, and reicipllon 
 anoiher ; nor ihd thry anil Iteid mean hy rnieption 
 the same thing. — II.
 
 374 
 
 ON THE INTELLECTUAL POWERS. 
 
 LeSSAY IV. 
 
 fully to what we are conscious of in this 
 operation, we shall find no more reason to 
 tliink that im.ages do really exist in our 
 minds, than that balances and other me- 
 chanical engines do. 
 
 We know of nothing that is in the mind 
 but by consciousness, and we are conscious 
 of nothing but various modes of thinking ; 
 such as understanding, willing, affection, 
 passion, doing, suffering. If philosophers 
 choose to give the name of an idea to any 
 mode of thinking of which we are conscious, 
 I have no objection to the name, but that 
 it introduces a foreign word into our lan- 
 guage without necessity, and a word that is 
 very ambiguous, and apt to mislead. But, 
 if they give that name to images in the 
 mind, which are not thought, but only 
 objects of thought, I can see no reason to 
 think that there are such things in nature. 
 If they be, their existence and their nature 
 must be more evident than anything else, 
 because we know nothing but by their 
 means. I may add, that, if they be, we 
 can know nothing besides them. For, from 
 the existence of images, we can never, by 
 any just reasoning, infer the existence of 
 anything else, unless perhaps the existence 
 of an intelligent Author of them. In this, 
 Bishop Berkeley reasoned right. [393] 
 
 In every work of design, the work must 
 be conceived before it is executed — that is, 
 before it exists. If a model, consisting of 
 ideas, must exist in the mind, as the ob- 
 ject of this conception, that model is a work 
 of design no less than the other, of which 
 it is the model ; and tlierefore, as a work of 
 design, it must have been conceived before 
 it existed. In every work of design, there- 
 fore, the conception must go before the 
 existence. This argument we applied be- 
 fore to the Platonic system of eternal and 
 immutable ideas, and it may be applied with 
 equal force to all the systems of ideas. 
 
 If now it should be asked, What is the 
 idea of a circle ? I answer, It is the con- 
 ception of a circle. What is the immediate 
 object of this conception ? The immediate 
 and the only object of it is a circle. But 
 where is this circle ? It is nowhere. If 
 it was an individual, and had a real ex- 
 istence, it must have a place ; but, being an 
 universal, it has no existence, and therefore 
 no place. Is it not in the mind of him that 
 conceives it ? The conception of it is in 
 the mind, being an act of the mind ; and in 
 common language, a thing being in the 
 mind, is a figuratiTe expression, signify- 
 ing that the thing is conceived or remem- 
 bered. 
 
 It may be asked. Whether this concep- 
 tion is an image or resemblance of a circle ? 
 I answer, I have already accounted for its 
 being, in a figurative sense, called the image 
 of a circle in the mind. If the question is 
 
 meant in the literal sense, we must observe, 
 that the word conception has two meanings. 
 Properly it signifies that operation of the 
 mind which we have been endeavouring to 
 explain ; but sometimes it is put for the 
 object of conception, or thing conceived. 
 
 Now, if the question be understood in tho 
 last of these senses, the object of this con- 
 ception is not an image or resemblance of 
 a circle ; for it is a circle, and nothing can 
 be an image of itself. [394] 
 
 If the question be — Whether the opera- 
 tion of mind in conceiving a circle be an 
 image or resemblance of a circle ? I think 
 it is not ; and that no two things can be 
 more perfectly unlike, than a species of 
 thought and a species of figure. Nor is it 
 more strange that conception should have 
 no resemblance to the object conceived, 
 than that desire should have no resem- 
 blance to the object desired, or resentment 
 to the object of resentment. 
 
 I can likewise conceive an individual 
 object that really exists, such as St Paul's 
 Church in London. I have an idea of it ; 
 that is, I conceive it. The immediate 
 object of this conception is four hundred 
 miles distant ; and I have no reason to think 
 that it acts upon me, or that I act upon it ; 
 but I can think of it notwithstanding. I 
 can think of the first year or the last year 
 of the Julian period. 
 
 If, atter all, it should te thought that 
 images in the mind serve to account for this 
 facultv of conceiving things most distant in 
 time and place, and even things which do 
 not exist, which otherwise would be alto- 
 gether inconceivable ; to this I answer, 
 that accounts of things, grounded upon 
 conjecture, have been the bane of true 
 philosophy in all ages. Experience may 
 satisfy us that it is an hundred times more 
 probable that they are false than that they 
 are true. 
 
 This account of the faculty of conception, 
 by images in the mind or in the brain, 
 will deserve the regard of those who have 
 a true taste in philosophy, when it is proved 
 by solid arguments —/"ir.y/. That there are 
 images in the. mind, or in the brain, of the 
 things we conceive. Secondly, That there 
 is a faculty in the mind of perceiving such 
 images. Thirdly, That the perception of 
 such images produces the conception of 
 things most distant, and even of things that 
 have no existence. And, fourthly, That 
 the perception of individual images in the 
 mind, or in the brain, gives us the concep- 
 tion of universals, which are the attributes 
 of many individuals. [395] Until this is 
 done, the theory of images existing in the 
 mind or in the brain, ought to be placed in 
 the same category with the sensible species, 
 materia prima of Aristotle, and the vortices 
 of Des Cartes.
 
 cuAP. III.] MISTAKES CONCERNING CONCEPTION. 
 
 375 
 
 CHAPTER III. 
 
 MISTAKES CONCEKNING CONCEPTION. 
 
 1. Writers on logic, after the example 
 of Aristotle, divide the operations of the 
 uuderstandmg into three : Simple Appre- 
 hension, (which is another word for Con- 
 ception,) Judgment, and Reasoning. They 
 teach us, that reasouing is expressed by a 
 syllogism, judgment by a proposition, and 
 simple apprehension by a term only — that 
 is, by one or more words which do not 
 make a full proposition, but only the sub- 
 ject or predicate of a proposition. If, by 
 this they mean, as I tliink they do, that a 
 proposition, or even a syllogism, may not 
 be simply apprehended,* I believe this is a 
 mistake. 
 
 In all judgment and in all reasoning, 
 conception is included. We can neither 
 judge of a proposition, nor reason about it, 
 unless we conceive or apprehend it. We 
 may distinctly conceive a proposition, with- 
 out judging of it at all. We may have no 
 evidence on one side or the other ; we may 
 have no concern whether it be true or false. 
 In these cases we commonly form no judg- 
 ment about it, though we perfectly under- 
 stand its meaning. -f- 
 
 A man may discourse, or plead, or write, 
 for other ends than to find the truth. His 
 learning, and wit, and invention may be 
 employed, while his judgment is not at all, 
 or very little. AVhen it is not truth, but 
 some other end he pursues, judgment would 
 be an impediment, unless for discovering 
 the means of attaining his end ; and, there- 
 fore, it is laid aside, or employed solely for 
 that purpose. [39(>1 
 
 The business of an orator is said to be, 
 to find out what is fit to persuade. This a 
 man may do with much ingenuity, who 
 never took the trouble to examine whether 
 it ought to persuade or not. Let it not be 
 thought, therefore, that a man judges of 
 the truth of every proposition he utters, or 
 hears uttered. In our commerce with the 
 world, judgment is not the talent that bears 
 the greatest price ; and, therefore, those who 
 are not sincere lovers of truth, lay up this 
 talent where it rusts and corru])ts, wjiile 
 they carry others to market, for vvhich 
 there is greater demand. 
 
 2. The division commonly made by logi- 
 
 * Does Reid here mean, by apprchendinR Wm;i^/, 
 apprchcudiiig in one ^implL• and indivisible act ? — 11. 
 
 \ There is no concepti'in po^s blc withnut a judg- 
 ment aHinning its (ideal) exisleiiee. 'I'here is no 
 t/injicioiii/icss, in fact, possible without judj!inent. 
 See above, p. 243, a, note *. It is to l)C observed, 
 that Iteid uses conci']iti(in in the course of this chap, 
 ler as convertible with uiiilrrxfiiiuliiir/ or caiiipriiifii. 
 Sinn ; ;ind, therefore, as we sliall see, in a vaguer or 
 m' re extensive rneaiiinK than the philosophers whose 
 opinion he controvert". — II. 
 
 cians, of simple apprehension, into Sensation, 
 Imagination, and Pure Intellection, seems 
 to me very improper in several respects. 
 
 First, Under the word sensation, they 
 include not only what is properly so called, 
 but the perception of external objects by 
 the senses. These are very difierent opera- 
 tions of the mind ; and, although they are 
 commonly conjoined by nature, ought to be 
 carefully distinguished by philosophers. 
 
 Secondly, Neither sensation nor the percep- 
 tion of external objects, is simple apprehen- 
 sion. Both includejudgment and belief, which 
 are excluded from simple apprehension." 
 
 Thirdly, They distinguish imagination 
 from pure intellection by this, that, in 
 imagination, the image is in the brain if in 
 pure intellection, it is in the intellect. This 
 is to ground a distinction upon an hypo- 
 thesis. AV^e have no evidence that there 
 are images either in the brain or in the in- 
 tellect, [397] 
 
 I take imagination, in its most proper 
 sense, to signify a lively conception of 
 objects of sight. + This is a talent of im- 
 portance to poets and orators, and deserves 
 a proper name, on account of its connection 
 with those arts. According to this strict 
 meaning of the word, imagination is dis- 
 tinguished from conception as a part from 
 the whole. AVe conceive the objects of the 
 other senses, but it is not so proper to say 
 that we imagine them. We conceive judg- 
 ment, reasoning, propositions, and argu- 
 ments ; but it is rather improper to say 
 that we imagine these things. 
 
 This distinction between imagination and 
 conception, may be illustrated by an ex- 
 ample, which Des Cartes uses to illus- 
 trate the distinction between imagination 
 and pure intellection. We can imagine a 
 triangle or a square so clearly as to 
 distinguish them from every other figure. 
 But we cannot imagine a figure of a thou- 
 sand equal sides and angles so clearly. The 
 best eye, by looking at it, could not distin- 
 guish it from every figure of more or fewer 
 sides. And that conception of its appear- 
 ance to the eye, which we ])roperly call im- 
 agination, cannot be more disthict than the 
 aiipearance it.self ; yet we can conceive a 
 figure oi a thousand sides, and even can 
 demonstrate the properties which distinguish 
 it from all figures of more en- frwor sides. 
 It is not by the eye, but by a superior fa- 
 culty, that we form the notion of a great 
 
 * See the last note.— II.' 
 
 \ Hut not Ihe image, of whicli the mind is con- 
 scious. Uy image or idea iii the brain, fiiicifS iiii- 
 jircssa, SfC, was ineaiit only the iiiikiKiwn corporeal 
 aiitecideiit of- the known imiilal (on»e(H.cnl, -the 
 iinai;e or idea In the mind, tlie ,v;«(/<'.« iJiinssii . fiC. 
 Ueid litre refers pi iiui)iHlly to the t'.irteslan doclrine. 
 — II. 
 
 X .See above, p. 'M'l, a, note ♦ ; and, lielnw. iiiide. 
 p. W .- II.
 
 37t) 
 
 ON THE INTELLECTUAL POWERS. 
 
 [^ESS^i 
 
 AY IV 
 
 number, such as a thousand. And a distinct 
 uotion of this number of sides not being to 
 be got by the eye, it is not imagined, but 
 it is distinctly conceived, and easily distin- 
 guished from every other number." 
 
 3. Simple apprehension is commonly re- 
 presented as the first operation of the 
 understanding ; and judgment, as being a 
 composition or combination of simple appre- 
 hensions. 
 
 This mistake has probably arisen from the 
 taking sensation, and the perception of 
 objects by the senses, to be nothing but 
 simple apprehension. They are, very pro- 
 bably, the first operations of the mind ; but 
 they are not simple apprehensions. -f" [398] 
 
 It is generally allowed, that we cannot 
 conceive sounds if we have never heard, 
 nor colours if we have never seen ; and the 
 same thing may be said of the objects of 
 the other senses. In like manner, we must 
 have judged or reasoned before we have 
 the conception or simple apprehension of 
 judgment and of reasoning. 
 
 Simple apprehension, therefore, though 
 it be the simplest, is not the first operation 
 of the understanding ; and, instead of say- 
 ing that the more complex operations of 
 the mind are formed by compounding sim- 
 ple apprehensions, we ought rather to say, 
 that simple apprehensions are got by ana- 
 lysing more complex operations, 
 
 A similar mistake, which is carried 
 through the whole of Mr Locke's Essay, 
 may be here mentioned. It is, that our 
 simplest ideas or conceptions are got im- 
 mediately by the senses, or by conscious- 
 ness, and the complex afterwards formed 
 by compounding them. I apprehend it is 
 far otherwise. 
 
 Nature presents no object to the senses, 
 or to consciousness, that is not complex. 
 Thus, by our senses we perceive bodies of 
 various kinds ; but every body" is a com- 
 plex object ; it has length, breadth, and 
 thickness ; it has figure, and colour, and 
 various other sensible qualities, which are 
 blended together in the same subject ; and 
 I apprehend that brute animals, who have 
 the same senses that we have, cannot sepa- 
 rate the different qualities belonging to the 
 same subject, and have only a complex 
 and confused notion of the whole. Such 
 also would be our notions of the objects of 
 sense, if we had not superior powers of 
 understanding, by which we can analyse 
 the complex object, abstract every parti- 
 cular attribute from the rest, and form a 
 distinct conception of it. 
 
 So that it is not by the senses imme- 
 
 * See above, p. 3fi6,a, note *.— H. 
 
 t They are not sintple npjrrehftuions, in one sense 
 — that is, the objects are not iiicoriBpositc. But this 
 was not the meaning in which the expression was used 
 by the Logicians. — H. 
 
 diately, but rather by the powers of ana> 
 lysing and abstraction, that we get the most 
 simple and the most distinct notions eveji 
 of the objects of sense. This will be more 
 fully explained in another place. [399] 
 
 4. There remains another mistake con- 
 cerning conception, which deserves to be 
 noticed. It is — That our conception of 
 things is a test of their possibility, so that, 
 what we can distinctly conceive, we may 
 conclude to be possible ; and of what is im- 
 possible, we can have no conception. 
 
 This opinion has been held by philoso- 
 phers for more than an hundred years, 
 without contradiction or dissent, as far as I 
 know ; and, if it be an error, it may be of 
 some use to inquire into its origin, and the 
 causes that it has been so generally re- 
 ceived as a maxim whose truth could not 
 be brought into doubt. 
 
 One of the fruitless questions agitated 
 among the scholastic philosophers in the 
 dark ages' was — What is the criterion of 
 truth ? as if men could have any other way 
 to distinguish truth from error, but by the 
 right use of that power of judging which 
 God has given them. 
 
 Des Cartes endeavoured to put an end to 
 this controversy, by making it a fundamen- 
 tal principle in his system, that whatever 
 we clearly and distinctly perceive, is true.-f 
 
 To understand this principle of Des 
 Cartes, it must be observed, that he gave 
 the name of perception to every power of 
 the human understanding : and in explain- 
 ing this very maxim, he tells us that sense, 
 imagination, and pure intellection, are only 
 different modes of jjerceiving, and, so the 
 maxim was understood by all his followers. J 
 
 The learned Dr Cudworth seems also to 
 have adopted this principle: — "The cri- 
 terion of true knowledge, says he, is only 
 to be looked for in our knowledge and con- 
 ceptions themselves : for the entity of all 
 theoretical truth is nothing else but clear 
 intelligibility, and whatever is clearly con- 
 ceived is an entity and a truth ; but that 
 which is false, divine power itself cannot 
 make it to be clearly and distinctly under- 
 stood. [400] A falsehood can never be 
 clearly conceived or apprehended to be 
 true." — " Eternal and Immutable Mora- 
 lity," p. 172, &c. 
 
 This Cartesian maxim seems to me to 
 have led the way to that now under con- 
 sideration, which seems to havebeen adopted 
 as the proper correction of the former. 
 When the authority of Des Cartes declined, 
 men began to seeithat we may clearly and 
 distinctly conceive what is not true, but 
 
 * This was more a question with the Greek philo- 
 sophers than with the schoolmen. — H. 
 
 t In this, he proposed nothing new. -H. 
 
 ij: i'hat is, in Oes Cartes' sigjiificalion of the word, 
 different modes of bein" conscious. See above.— il. 
 
 [.398-100]
 
 CUAl'. 
 
 in.J 
 
 MISTAKES CONCERNING CONCEPTION. 
 
 377 
 
 thought, that our conception, though not in 
 all cases a test of truth, might be a test of 
 possibility.* 
 
 This indeed seems to be a necessary con- 
 sequence of the received doctrine of ideas ; 
 it being evident that there can bo no dis- 
 tinct image, either in tlie mind or anywhere 
 else, of that which is impossible. -f The 
 ambiguity of the word coticeivr, which we 
 observed, Essay I. chap. 1, and the com- 
 mon phraseology of saying loe cannot con- 
 ceive such a tliinij, when we would signify 
 that we think it impossible, might likewise 
 contribute to the reception of this doctrine. 
 
 But, whatever was the origin of this 
 opinion, it seems to prevail universally, 
 and to be received as a maxim. 
 
 " The bare having an idea of the propo- 
 sition proves the thing not to be impossible ; 
 for of an impossible proposition there can 
 be no idea." — Dr Samuel Clarke. 
 
 " Of that which neither does nor can 
 exist we can have no idea." — Lord Bolinu- 
 
 BROKE. 
 
 " The measure of impossibility to us is 
 inconceivableness, that of which we can 
 have no idea, but that reflecting upon it, it 
 appears to be nothing, we ])ronounce to be 
 impossible." — Abkrnethv. [401] 
 
 " In every idea is implied the possibility 
 of the existence of its object, nothing being 
 clearer than that there can be no idea of 
 an impossibility, or conception of what can- 
 not exist." — Dr Price- 
 
 " Impossibile est cujus nuUam notionem 
 formare possumus ; possibile e contra, cui 
 aliqua respondet notio." — Wolfii Ontolo- 
 GiA.:}: 
 
 " It is an established maxim in metaphy- 
 sics, that whatever the mind conceives, in- 
 cludes the idea of possible existence, or, in 
 other words, that nothing we imagine is 
 absolutely impossible." — D. Hume. 
 
 It were easy to muster up many otlior 
 respectable authorities for this maxim, and 
 I have never found one that called it in 
 question. 
 
 If the maxim be true in the extent wliicli 
 
 * That is, of logical possibility— the absence of con. 
 tradictioi). — H. 
 
 ^ riiis is rather a strained inference. — H. 
 
 :; 'I'hcse are not exactly Wolf's expressions. See 
 '* Ontuldiiu," Ij ^ KhJ, 103; •' Philiisoiiliin /{iiti<inali.i," 
 ^5 ^■^■i, b'c8. Ihe same doctrine is lield by Tschir?!. 
 haiiseii and others. In so far, however, as it is said 
 that inc(inci:ivnljitily is the criterion of im|)OS'iibility, 
 it is manilestly erroneous. Of many contradictories, 
 we are able to conceive neither; l)iit, by the law of 
 thouRht, called that of Excluded Muldle, one ol two 
 roiitradirtorics must be admitte<l— must be true. 
 For example, we can neither c(in('eive, on tlie one 
 hand, an ultimate minimum of spaceorof time ; nor 
 can we, on the other, conceive their infinite divikil)i- 
 liiy. In like manner, wecanno; coiK-eive the al)»"- 
 lutecommenceuieiit of time, or the utinuht liniii of 
 upare, und are yet equally unable to conceive Iheni 
 without any cominenieineni or limit. 'I lie absnrdiiy 
 that would refull from the asM-rlioii, lli.it all that is 
 inconceivable is imposiiible. is thus obvious ; and so 
 far Iteid's criticism is ju»i, though not new. — II. 
 
 [101, 102] 
 
 the famous Wolfius has given it in the pas- 
 sage above quoted, we shall have a short 
 road to the determination of every question 
 about the possibility or impossibility of 
 things. We need only look into our own 
 breast, and that, like the Urim and 
 Thummim, will give an infallible answer. 
 If we can conceive the thing, it is possible ; 
 if not, it is impossible. And, surely, every 
 man may know whether he can conceive 
 what is affirmed or not. 
 
 Other philosophers have been, satisfied 
 with one half of the maxim of Wolfius. 
 They say, that whatever we can conceive is 
 possible ; but they do not say that whatever 
 we cannot conceive is impossible. 
 
 I cannot help thinking even this to be a 
 mistake, which philosophers have been un- 
 warily led into, from the causes before men- 
 tioned. My reasons are these : — [402] 
 
 1. Whatever is said to be possible or im- 
 possilile, is expressed by a proposition. 
 Now, what is it to conceive a proposition ? 
 I think it is no more than to understand 
 distinctly its meaning.* I know no more 
 
 * In this sense of the word Conception, I make 
 bold to say that there is no philosopher who evtr 
 held an opinion different from t!iat of our author. 
 'I'he whole dispute arises from Iteid giving a wider 
 signification to this term thin that which it h.is 
 generally received. In his view, it has two mean, 
 ings; in that of tlie pliilosopliers whom he attacks, 
 it has only one. To illustrate this, t.ikc the proposi. 
 tioii — a circlf is aqiian: Here we easily understand 
 the meaning of the affirmation, because what is neces. 
 sary to an act of judgment is merely that the subject 
 and predicate should be brought into a unity of rela- 
 tion. A judgment is therefore possible, even where 
 the two terms are contradictory. Hut the philosophers 
 never expressed, by the term conception, this under, 
 standing of the purport of a proposition. What they 
 meant by conception was not the unity of relation, 
 but. the unity iif reprisentalion ; and this unity of 
 representation tiicy made the criterion of logical pos. 
 sibility. 1 o take the example already given : they 
 did not say a circle may possibly be square, because 
 we can understand the meaiiiiii.^ of the proposition, 
 a circle is square ; but, on the conirary, they said it 
 is impossible that a circle can be square, and the pro. 
 piisition affirming tins is necessarily false, bec.iuse we 
 cannot, in consciousness, bring to a unity o/reprc- 
 sentalion the repugnant notions, circle and square- 
 that IS, coneeire the notion ol sipuire cirele. Heid's 
 mistake in this matter is so palpable that it is not 
 more surprising that he should have committed it, 
 than that so many should not only have followed him 
 in the opinion, but even have laudiHl it as the lefiita. 
 tion of an important error. To shew how cum- 
 ))|elely Held mistonk the philosophers, it will be suf- 
 ficient to ipiote a passage from Wolfs vernacular 
 Logic, which 1 take from the English translation, 
 (one, by the bv, of Ihe liw tolerable versions we have 
 of (ierman ph'iloscii.hical works,) pulilished in n7U:— 
 
 " It is carcfcilly to be oliserved, that we have not 
 always the notion of theihing present to us, or in 
 view, when we speak or think of it ; liiit are satisfied 
 when we imaKin;' w • sufficwntlv llnlle^^talld what we 
 speak, if we think we neollcct that we li ive li.-id, at 
 another lime, the nolinii which is tobe joiiii'd tothis 
 or the other woid ;• .mil thus we represent lo our. 
 selves, as at a dimaiice oi.ly, or obscurely, the iliing 
 denoted by thc> term. 
 
 " Hence, it uually happensthat, when wecombine 
 words logithcr, lo each of which, apart, a meanuiK 
 or notion aii»wer«, we imagine we undirstan I wliiit 
 we.ulier, lliough that which isdenoled by such com. 
 billed words he impossihle. and coiiscipiinllv ran 
 have no me.iniiiB. Kor tlinl which u impossible u
 
 378 
 
 ON THE INTELLECTUAL POWERS, 
 
 [essay IV. 
 
 that can be meant by simple apprehension 
 or conception, when apphed to a proposi- 
 tion. The axiom, therefore, amounts to 
 this : — Every proposition, of which you un- 
 derstand the meaning distinctly, is possible. 
 I am persuaded that I understand as dis- 
 tinctly the meaning of this proposition, //«v 
 two sides of a trianijle are together equal 
 to the third, as of this — Any tivo sides nf a 
 triangle are totjether greater than, the third ; 
 yet the first of these is impossible. 
 
 Perhaps it will be said, that, though you 
 understand the meaning of the impossible 
 proposition, you cannot suppose or conceive 
 it to be true. 
 
 Here we are to examine the meaning of 
 the phrases of supposing and conceiving a 
 proposition to be true. I can certainly sup- 
 pose it to be true, because I can draw con- 
 sequences fnjrn it which I find to be impos- 
 sible, as well as the proposition itself. 
 
 If, by conceiving it to be true, be meant 
 giving some degree of assent to it, how- 
 ever small, this, I confess, I cannot do. 
 But will it be said that every proposition to 
 which I can give any degree of assent, is 
 possible ? This contradicts experience, and, 
 therefore, the maxim cannot be true in 
 this sense. 
 
 Sometimes, when we say that we cannot 
 conceive a thing to be true, we mean by that 
 expression, ihaX we judge it to be impossible. 
 In this sense I cannot, indeed, conceive 
 it to be true, that two sides of a triangle 
 are equal to the third. I judge it to be 
 impossible. If, then, we understand, in 
 this sense, that maxim, that nothing we can 
 conceive is impossible, the meaning will 
 be, that nothing is impossible which we 
 judge to be possible. But does it not often 
 happen, that what one man judges to be 
 possible, another man judges to be impos- 
 sible ? The maxim, therefore, is not true 
 in this sense. [403] 
 
 I am not able to find any other meaning 
 of conceiving a proposition, or of conceiving 
 it to be true, besides these I have men- 
 tioned. I know nothing that can be meant 
 by having the idea of a proposition, but 
 
 nothing at all, and of nothing there can be no idea. 
 For instance, we have a notion of gold, as also of 
 iron. But it is impossible that iron can at the same 
 time 1 egold, consequently, neither can we have any 
 notion of iron-goKl ; and yet we understand what 
 people mean when they mention iron-gold. 
 
 " In the instance alleged, it certainly strikes every 
 one, at first, that the expre-sion iron. gold is an empty 
 sound ; but yet there aiv a thousand instances in which 
 it does not so easily strike. For example, when I 
 say a rectilineal two-lined figure, a figure contained 
 under two right lines, I am equallv well understood 
 as when I say. a riglit-lined triangle, a figure c n- 
 tained uni'er three right lines. .Audit should seem 
 we had a distinct notion of both figures. However, 
 as we shew in Geometry that two right lines can 
 never contain space, it is also impossible to form a 
 notion of a rectilineal two.lined figure; and conse- 
 quently that expression is an empty sound."— F. .%. 
 
 either the understanding its meaning, or 
 the judging of its truth. I can understand 
 a proposition that is false or impossible, as 
 well as one that is true or possible ; and I 
 find that men have contradictory judgments 
 about what is possible or impossible, as well 
 as about other things. In what sense then 
 can it be said, that the having an idea of a 
 proposition gives certain evidence that it is 
 possible ? 
 
 If it be said, that the idea of a proposition 
 is an image of it in the mind, I think indeed 
 there cannot be a distinct image, either in 
 the mind or elsewhere, of that which is 
 impossible ; but what is meant by the image 
 of a proposition I am not able to compre- 
 hend, and I shall be glad to be informed. 
 
 2. Every proposition that is necessarily 
 true stands opposed to a contradictory pro- 
 position that is impossible ; and he that 
 conceives one conceives both. Thus a man 
 who believes that two and three necessarily 
 make five, must believe it to be impossible 
 that two and three should not make five. 
 He conceives both propositions when he 
 believes one. Every proposition carries its 
 contradictory in its bosom, and both ai'e 
 conceived at the same time. " It is con- 
 fessed," says Mr Hume, " that, in all cases 
 where we dissent from any person, we con- 
 ceive both sides of the question ; but we 
 can believe only one." From this, it cer- 
 tainly follows, that, when we dissent from 
 any person about a necessary proposition, 
 we conceive one that is imposible ; yet I 
 know no philosopher who has made so 
 much use of the maxim, that whatever we 
 conceive is possible, as Mr Hume. A great 
 part of his peculiar tenets is built upon it ; 
 and, if it is true, they must be true. But 
 he did not perceive that, in the passage 
 now quoted, the truth of which is evident, 
 he contradicts it himself. [404] 
 
 3. Mathematicians have, in many cases, 
 proved some things to be possible, and 
 others to be impossible, which, without 
 demonstration, would not have been be- 
 lieved. Yet I have never found that any 
 mathematician has attempted to prove a 
 thing to be possible, because it can be con- 
 ceived ; or impossible, because it cannot be 
 conceived.* Why is not this maxim applied 
 to determine whether it is possible to square 
 the circle ? a point about which very emi- 
 nent mathematicians have differed. It is 
 easy to conceive that, in the infinite series 
 of numbers, and intermediate fractions, 
 some one number, integral or fractional, 
 may bear the same ratio to another, as the 
 side of a square bears to its diagonal ;-|- yet, 
 
 * All geometry is, in fact, founded on our intui. 
 tions of space— tliat is, in commi.n language, on our 
 conceptions of space and its relations. — H. 
 
 t We are able to conceive nothing infinite; .nndwe 
 inav supjKise, hut we cannot conceive, represent, or 
 imaainr, the possibility in question. — H. 
 
 [403, 404]
 
 CHAP. IV.] OF THE TRAIN OF THOUGHT IN THE MIND. 379 
 
 liowever conceivable this may be, it may be 
 demonstrated to be impossible. 
 
 4. Mathematicians often require us to 
 conceive things that are impossible, in order 
 to prove them to be so. This is the case in 
 all their demonstrations ad ahsurdum. 
 Conceive, says Euclid, a right line drawn 
 from one point of the circumference of a 
 circle to another, to fall without the circle :* 
 I conceive this — I reason from it, until I 
 come to a consequence that is manifestly 
 absurd ; and from thence conclude that the 
 thing which I conceived is impossible. 
 
 Having said so much to shew that our 
 power of conceiving a proposition is no 
 criterion of its possibility or impossibility, I 
 shall add a few observations on the extent 
 of our knowledge of this kind. 
 
 1. There are many propositions which, 
 by the faculties God has given us, we judge 
 to be necessary, as well as true. All 
 mathematical propositions are of this kind, 
 and many others. The contradictories of 
 Buch propositions must be impossible. Our 
 knowledge, therefore, of what is impossible, 
 must, at least, be as extensive as our know- 
 ledge of necessary truth. 
 
 2. By our senses, by memory, by testi- 
 mony, and by other means, we know many 
 things to be true which do not apjiear to be 
 necessary. But whatever is true is pos- 
 sible. Our knowledge, therefore, of what is 
 possible must, at least, extend as far as our 
 knowledge of truth. [405] 
 
 3. If a man pretends to determine the 
 possibility or impossibility of things beyond 
 these limits, let him bring proof. I do not 
 say that no such proof can be brought. It 
 has been brought in many cases, particu- 
 larly in mathematics. But I say that his 
 being able to conceive a thing, is no proof 
 that it is possible. i" Mathematics afford 
 many instanceB of impossibilities in the 
 nature of things, which no man would have 
 believed if they had not been strictly de- 
 monstrated. Perhaps, if we were able to 
 reason demonstratively in other subjects, to 
 as great extent as in mathematics, we might 
 find many things to be impossible, which 
 we conclude without hesitation, to be pos- 
 sible. 
 
 It is possible, you say, that God might 
 have made an universe of sensible and ra- 
 tional creatures, into which neither natural 
 nor moral evil should ever enter. It may 
 be so, for what I know. But how do you 
 know that it is possible ? That you can 
 conceive it, I grant ; but this is no proof. 
 
 * Euclid doos not require us to conceive or imaRine 
 any such iinpossitjility. Tlie propiwiliori to which 
 Rciri iinisi rcfc-r, is the second of the third Book ot 
 the KIcint-iits. — II. 
 
 t Not, ccrl.-iirily, that it is renlh/ ji/ixxilile, but that 
 It is proljltmiiliidlh/ imnili/i'—i. e., involves no i iiii- 
 tradictiun — violates no law if thought. i'hiii lallcr 
 is that nosbibilitv nlonc in riiiifclion. — II. 
 
 [40.V 40(i 
 
 I cannot admit, as an argument, or even as 
 a pressing difficulty, what is grounded on 
 the supposition that such a thing is possible, 
 when there is no good evidence tliat it is 
 possible, and, for anything we know, it may, 
 in the nature of things, be impossible. 
 
 CHAPTER IV. 
 
 OF THE TRAIN OF THOUGHT IN THE MIND. 
 
 Every man is conscious of a succession 
 of thoughts which pass in his mind while he 
 is awake, even when they are not excited 
 by external objects. [406] 
 
 The mind, on this account, may be com- 
 pared to hquor in the state of fermentation. 
 When it is not in this state, being once at 
 rest, it remains at rest, until it is moved by 
 some external impulse. But, in the state 
 of fermentation, it has some cause of motion 
 in itself, which, even when there is no im- 
 pulse from without, suffers it not to be at 
 rest a moment, but produces a constant 
 motion and ebullition, while it continues to 
 ferment. 
 
 There is surely no similitude between 
 motion and thought ; but there is an analogy, 
 so obvious to all men, that the same words 
 are often applied to both ; and many modi- 
 fications of thought have no name but such 
 as is borrowed from the modifications of 
 motion. Many thoughts are excited by the 
 senses. The causes or occasions of these 
 may be considered as external. But, when 
 such external causes do not operate upon 
 us, we continue to think from some internal 
 cause. From the constitution of the mind 
 itself there is a constant ebullition of thought, 
 a constant intestine motion ; not only of 
 thoughts barely speculative, but of scnti- 
 ments,passions, and afi'ections, which attend 
 them. 
 
 This continued succession of thought has, 
 by modern philosophers, been called the 
 imagination. * I think it was formerly called 
 the fancy, or the phanloay.-f If the old 
 name be laid aside, it were to be wished 
 that it had got a name less ambij;uous than 
 that of imagination, a name which had two 
 or three meanings besides. 
 
 It is often called the Iraiu of ideas. This 
 may lead one to think that it is a train of 
 bare conceptions ; but this would surely be 
 a mistake. It is made up of many other 
 operations of iiiiiid, as well as of concep- 
 tions, or ideas. 
 
 * Hy some only, and that imjiropcrly.— 11. 
 
 t 'Ihe l.atin liiui;!iii<ilin, Willi ilH niodilicalions in 
 the vul(?.ir laiigua>!<», W.1S iinplnytd liolli in ancient 
 and niodcrn times to express «lial the Urecks -(leno. 
 min.ited •I'«vT«ff-a. /V«/;i^i.«.v, ot whieli I'haii.ti/ i>r 
 luiiiiii is a corruption, and now vniployed in a m"ie 
 liniili'd Kcnse, wan a eoniiiioii n.inie for Imaninalion 
 with lI.eoM liuKlisli uritcrs.— II.
 
 380 
 
 ON THE INTELLECTUAL POWERS 
 
 Qessa V 
 
 III. 
 
 Memory, judgment, reasoning, passions, 
 affections, and purposes — in a word, every 
 operation of the mind, excepting tliose of 
 sense — is exerted occasionally in tliis train 
 of thouglit, and has its share as an ingre- 
 dient : so that we must take the word idea 
 in a very extensive sense, if we make the 
 train of our thoughts to be only a train of 
 ideas. [407] 
 
 To pass from the name, and consider the 
 thin"', we may observe, that the trains of 
 thought in the mind arc of two kinds : they 
 are either such as How spontaneously, like 
 water from a fountain, without any exer- 
 tion of a governing principle to arrange 
 them ; or they are regulated and directed 
 by an active effort of the mind, with some 
 view and intention. 
 
 Before we consider these in their order, 
 it is proper to premise that these two kinds, 
 however distinct in their nature, are for 
 the most part mixed, in persons awake and 
 come to years of understanding. 
 
 On the one hand, we are rarely so vacant 
 of all project and desiga as to let our 
 thoughts take their own course, without 
 the least check or direction. Or if, at any 
 time, we should be in this state, some object 
 will present itself, which is too interesting 
 not to engage the attention and rouse the 
 active or contemplative powers that were 
 at rest. 
 
 On the other hand, when a man is giving 
 the most intense application to any specula- 
 tion, or to any scheme of conduct, when he 
 wills to exclude every thought that is fo- 
 reign to his present purpose, such thoughts 
 will often impertinently intrude upon him, 
 in spite of his endeavours to the contrary, 
 and occupy, by a kind of violence, some 
 part of tlie time destined to another pur- 
 pose. One man may have the command 
 of his thoughts more than another man, 
 and the same man more at one time than 
 at another. But, I apprehend, in the best 
 trained mind, the thoughts will sometimes 
 be restive, sometimes capricious and self- 
 willed, when we wish to have them most 
 under command. [408] 
 
 It has been observed very justly, that 
 we must not ascribe to the mind the power 
 of calling up any thought at pleasure, be- 
 cause such a call or volition supposes that 
 thought to be already in the mind ; for, 
 otherwise, how should it be the object of 
 volition ? As this must be granted on the 
 one hand, so it is no less certain, on the 
 other, thiit a man has a considerable power 
 in regulating and disposing his own thoughts- 
 Of this every man is conscious, and I can 
 no more doubt of it than I can doubt whether 
 I think at all. 
 
 We seem to treat the thoughts that pre- 
 sent themselves to the fancy in crowds, as 
 a great man treats those that attend his 
 
 levee. They are all ambitious of his at- 
 tention : he goes round the circle, bestow- 
 ing a bow upon one, a smile upon another ; 
 asks a short question of a third ; while a 
 fourth is honoured with a particular con- 
 ference ; and the greater part have no par- 
 ticular mark of attention, but go as they 
 came. It is true, he can give no mark of 
 his attention to those who were not there, 
 but he has a sufficient number for making 
 a choice and distinction. 
 
 In like manner, a number of thoughts 
 present themselves to the fancy spontane- 
 ously ; but, if we pay no attention to them, 
 nor hold any conference with them, they 
 pass with the crowd, and are immediately 
 forgot, as if they had never appeared. But 
 those to which we think proper to pay at- 
 tention, may be stopped, examined, and 
 arranged, for any particular purpose we 
 have in view. 
 
 It may likewise be observed, that a train 
 of thought, which was at first composed by 
 application and judgment, when it has 
 been often repeated, and becomes familiar, 
 will present itself spontaneously. Thus, 
 when a man has composed an air in music, 
 so as to please his own ear, after he has 
 played or sung it often, the notes will 
 arrange themselves in just order, and it 
 requires no effort to regulate their succes- 
 sion. [409] 
 
 Thus we see that the fancy is made up 
 of trains of thinking — some of which are 
 spontaneous, others studied and regulated, 
 and the greater part are mixed of both 
 kinds, and take their denomination from that 
 which is most prevalent ; and that a train 
 of thought which at first was studied and 
 composed, may, by habit, present itself 
 spontaneously. Having premised these 
 things, let us return to those trains of 
 thought which are spontaneous, which must 
 be first in the order of nature. 
 
 When the work of the day is over, and a 
 man lies down to relax his body and mind, 
 he cannot cease from thinking, though he 
 desires it. Something occurs to his fancy ; 
 that is followed by another thing ; and so his 
 thoughts are carried on from one object to 
 another, until sleep closes the scene. 
 
 In this operation* of the mind, it is not 
 faculty only that is employed; there are 
 many that join together in its production. 
 Sometimes the transactions of the day are 
 brought upon the stage, and acted over 
 again, as it were, upon this theatre of the 
 imagination. In this case, memory surely 
 acts the most considerable part, since the 
 scenes exhibited are not fictions, butrealities, 
 which we remember ; yet, in this case, the 
 
 * J he word process might be here preferable. 
 Opcratiim would denote that the mind is active in 
 associating the train of thought. — H. 
 
 [407-409]
 
 CHAP. IV.] OF THE TRAIN OF THOUGHT IN THE MIND. 
 
 381 
 
 memory does not act alone, other powers are 
 employed, and attend upon their proper 
 objects. The transactions remembered will 
 be more or less interesting ; and we cannot 
 then review our own conduct, nor that of 
 others, without passing some judgment upon 
 it. This we approve, that we disapprove. 
 This elevates, that humbles and depresses 
 us. Persons that are not absolutely indif- 
 ferent to us, can hardly appear, even to the 
 imagination, without some friendly or un- 
 friendly emotion. We judge and reason 
 about things as well as persons in such 
 reveries. We remember what a man said 
 and did ; frum this we pass to his designs 
 and to his general character, and frame 
 some hypothesis to make the whole con- 
 sistent. Such trains of thought we may 
 call historical. [410] 
 
 There are others which we may call ro- 
 mantic, in which the plot is formed by the 
 creative power of fancy, without any regaril 
 to what did or will happen. In these also, 
 the powers of judgment, taste, moral senti- 
 ment, as well as the passions and affections, 
 come in and take a share in the execu- 
 tion. 
 
 In these scenes, the man himself com- 
 monly acts a very distinguished part, and 
 seldom does anything which he cannot ap- 
 prove. Here the miser will be generous, 
 the coward brave, and the knave honest. 
 Mr Addison, in the '-Spectator," calls this 
 play of the fancy, castle-building. 
 
 The young politician, who has turned his 
 thoughts to the affairs of government, be- 
 comes, in his imagination, a minister of 
 state. He examines every spring and wheel 
 of the machine of government with the 
 nicest eye and the most exact judgment. 
 He finds a proper remedy for every disorder 
 of the commonwealth, quickens trade arid 
 manufactures by salutary laws, encourages 
 arts and sciences, and makes the nation 
 happy at home and respected abroad. He 
 feels the reward of his good administration, 
 in that self-approbation which attends it, 
 and is happy in acquiring, by his wise and 
 patriotic conduct,theblessingsof the present 
 age, and the praises of those that are to 
 come. 
 
 It is probable that, upon the stage of 
 imagination, more great exploits have been 
 performed in every age than have been 
 upon the stage of life from the beginning of 
 the world. An innate desire of self-appro- 
 bation is undoubtedly a part of the human 
 constitution. It is a ])ovverful spur to 
 worthy conduct, and is intended as such by 
 the Author of our being. A man cannot 
 he easy or haj)])y, unless this desire be in 
 some measure gratified. Wiiile he con- 
 ceives hims;elf worthless and base, he can 
 relish no enjoyment. The humiliating, 
 mortifying sentiment nmst be removed, and 
 [+10-"U'^] 
 
 this natural desire of self-approbation will 
 either produce a noble effort to acquire real 
 worth, which is its proper direction, or it 
 will lead into some of those arts of self- 
 deceit, which create a false opinion of 
 worth. [411] 
 
 A castle-builder, in the fictitious scenes 
 of his fancy, will figure, not according to his 
 real character, but according to the highest 
 opinion he has been able to form of himself, 
 and perhaps far beyond that opinion. For, 
 in those imaginary conflicts, the passions 
 easily yield to reason, and a man exerts the 
 noblest efforts of virtue and magnanimity, 
 with the same ease as, in his dreams, he 
 flies through the air or plunges to the bot^ 
 torn of the ocean. 
 
 The romantic scenes of fancy arc most 
 commonly the occupation of young minds, 
 not yet so deeply engaged in life as to have 
 their thoughts taken up by its real cares 
 and business. 
 
 Those active powers of the mind, wliioli 
 are most luxuriant by constitution, or have 
 been most cherislied by education, im- 
 patient to exert themselves, hurry the 
 thought into scenes that give them play ; 
 and the boy commences in imagination, 
 according to the bent of his mind, a general 
 or a statesman, a poet or an orator. 
 
 When the fair ones become castle-build- 
 ers, they use different materials ; and, while 
 the young soldier is carried into the field of 
 Mars, where he pierces the thickest squad- 
 rons of the enemy, despising death in all 
 its forms, the gay and lovely nymph, whose 
 heart has never felt the tender jiassion, is 
 transported into a brilliant assembly, where 
 she draws the attention of every eye, and 
 makes an impression on tlie noblest heart. 
 
 But no sooner has Cnpid's arrow found 
 its way into her own heart, than the whole 
 scenery of her imagination is changed. 
 Balls and assemblies have now no charms. 
 Woods and groves, the flowery bank and 
 the crystal fountain, are the scenes she 
 frequents in imagination. She becomes an 
 Arcadian shepherdess, feeding her flock 
 beside that of her Strejihon, and wants no 
 more to complete her happiness. [412] 
 
 In a few years the love-sick maid is 
 transformed into the solicitous mother. Her 
 smiling ofl'spring jilay aroimd her. She 
 views them with a i)arent's eye. Her ima- 
 gination immediately raises tlient to man- 
 hood, and brings tiiem forth up. n the stage 
 of life. One son makes a figure in the 
 army, another shines at the bar ; her 
 daughters are hapi>ily disposed of in mar- 
 riage, and bring new alliances to the family. 
 Her children's children riK' up before her, 
 and venerate Inr grey liairs. 
 
 Thus the spontaneous sallies of faney :iie 
 as various as the cares and fears, the de- 
 sires and ho]>eB, of man.
 
 382 
 
 ON TUK INTELLECTUAL POWERS. 
 
 [essay IV. 
 
 Quicquid ap.iint homines, votum, tiinor, ir.i, voluptas, 
 Gaudia, discursus: 
 
 These fill up the scenes of fancy, as well 
 as the page of the satirist. Whatever 
 possesses the heart makes occasional ex- 
 cursions into the imagination, and acts such 
 scenes upon that theatre as are agreeable 
 to the prevailing passion. The man of 
 traffic, who has committed a rich cargo to 
 the inconstant ocean, follows it in his 
 thought, and, according as his hopes or his 
 fears prevail, he is haunted with storms, 
 and rocks, and shipwreck ; or he makes a 
 happy and a lucrative voyage, and, before 
 his vessel has lost sight of land, he has dis- 
 posed of the profit which she is to bring at 
 her return. 
 
 The poet is carried into the Elysian fields, 
 where he converses with the ghosts of 
 Homer and Orpheus. The philosopher makes 
 a tour through the planetary system, or 
 goes down to the centre of the earth, and 
 examines its various strata. In the devout 
 man likewise, the great objects that possess 
 his heart often play in his imagination : 
 sometimes he is transjiorted to the regions 
 of the blessed, from whence he looks down 
 with pity upon the folly and the pageantry 
 of human life; or he prostrates himself 
 before the throne of the Most High with 
 devout veneration ; or he converses with 
 celestial spirits about the natural and moral 
 kingdom of God, which he now sees only 
 by a faint light, but hopes hereafter to view 
 with a steadier and brighter ray. [413] 
 
 In persons come to maturity, there is, 
 even in these spontaneous sallies of fancj', 
 some arrangement of thought ; and I con- 
 ceive that it will be readily allowed, that' in 
 those who have the greatest stock of know- 
 ledge, and the best natural parts, even the 
 spontaneous movements of fancy will be 
 the most regular and connected. They 
 have an order, connection, and unity, by 
 ■which they are no less distinguished from 
 the dreams of one asleep, or the ravings of 
 one delirious on the one hand, than from 
 the finished productions of art on the other. 
 
 How is this regular arrangement brought 
 about ? It has all the marks of judgment 
 and reason, yet it seems to go before judg- 
 ment, and to spring forth spontaneously. 
 
 Shall we believe with Leibnitz, that the 
 mind was originally formed like a watch 
 wound up ; and that all its thoughts, pur- 
 poses, passions, and actions, are effected 
 by the gradual evolution of the original 
 spring of the machine, and succeed each 
 other in order, as necessarily as the motions 
 and pulsations of a watch ? 
 
 If a child of three or four years were put 
 to account for the phsenomena of a watch, 
 he V luld conceive that there is a little man 
 withiii the watch, or some other little animal, 
 that beats continually, and produces the 
 
 motion. Whether the hypothesis of this 
 young philosopher, in turning the watch- 
 spring into a man, or that of the German 
 philosopher, in turning a man into a watch- 
 spring, be the most rational, seems hard to 
 determine.* 
 
 To account for the regularity of our first 
 thoughts, from motions of animal spirits, 
 vibrations of nerves, attractions of ideas, or 
 from any other unthinking cause, whether 
 mechanical or contingent, seems equally 
 irrational. [414] 
 
 If we be not able to distinguish the 
 strongest marks of thought and design from 
 the effects of mechanism or contingency, the 
 consequence will be very melancholy ; foj 
 it must necessarily follow, that we have no 
 evidence of thought in any of our fellow 
 men — nay, that we have no evidence of 
 thought or design in the structure and go- 
 vernment of the universe. If a good period 
 or sentence was ever produced without 
 having had any judgment previously em- 
 ployed about it, why not an Iliad or .^neid ? 
 They differ only in less and more ; and we 
 should do injustice to the philosopher of 
 Laputa, in laughing at his project of making 
 poems by the turning of a wheel, if a con- 
 currence of unthinking causes may produce 
 a rational train of thought. 
 
 It is, therefore, in itself highly probable 
 to say no more, that whatsoever is regular 
 and rational in a train of thought, which 
 presents itself spontaneously to a man's 
 fancy, without any'study, is a copy of what 
 had been before composed by his own ra- 
 tional powers, or those of some other person. 
 
 We certainly judge so in similar cases. 
 Thus, in a book I find a train of thinking, 
 which has the marks of knowledge and 
 judgment. I ask how it was produced ? It 
 is printed in a book. This does not satisfy 
 me, because the book has no knowledge nor 
 reason. I am told that a printer printed 
 it, and a compositor set the types. Neither 
 does this satisfy me. These causes, per- 
 haps, knew very little of the subject. There 
 must be a prior cause of the composition. 
 It was printed from a manuscript. True. 
 But the manuscript is as ignorant as the 
 printed book. The manuscript was written 
 or dictated by a man of knowledge and 
 judgment. This, and this only, will satisfy 
 a man of common understanding ; and it 
 appears to him extremely ridiculous to be- 
 lieve that such a trahi of thinking could 
 originally be produced by any cause that 
 neither reasons nor thinks. [415] 
 
 Whether such a train of thinking be 
 printed in a book, or printed, so to speak, 
 in his mind, and issue spontaneously from 
 his fancy, it must have been composed with 
 
 * The theory of our mental nssociationso'esmuch 
 to the philosophers of Uic Leibnitziaii school.— H. 
 
 [41.3-415]
 
 CHAP. IV.] OF THE TRAIN OF THOUGHT IN THE MIND. 
 
 383 
 
 judgmeut by himself, or by some otlier 
 rational beiuj;. 
 
 This, I thiuk, will be confirmed by tracing 
 the progress of the human fancy as far 
 back as we are able. 
 
 We have not the means of knowing how 
 the fancy is employed in infants. Their 
 time is divided between the employment of 
 their senses and sound sleep : so tluvt there 
 is little time left for imagination, and the 
 materials it has to work upon are probably 
 very scanty. A few days after they are 
 born, sometimes a few hours, we see them 
 smile in their sleep. But what they smile 
 at is not easy to guess ; for they do not 
 smile at anything they see, when awake, 
 for some months after they are born. It 
 is likewise common to see them move their 
 lips in sleep, as if they were sucking. 
 
 These things seem to discover some 
 working of the imagination ; but there is 
 no reason to thiuk that there is any regular 
 train of thought in the mind of infants. 
 
 By a regular train of thought, I mean 
 that which has a beginning, a middle, and 
 an end, an arrangement of its parts, ac- 
 cording to some rule, or with some inten- 
 tion. Thus, the conception of a design, 
 and of the means of executing it ; the con- 
 ception of a whole, and the number and 
 order of the parts. These are instances of 
 the most simple trains of thought that can 
 be called regular. 
 
 Man has undoubtedly a power (whether 
 we call it taste or judgment is not of any 
 consequence in the present argument) 
 whereby he distinguishes between a com- 
 position and a heap of materials ; between 
 a house, for instance, and a heap of stones ; 
 between a sentence and a heap of words ; 
 between a picture and a heap of colours. 
 [41()J It does not appear to me that chil- 
 dren have any regular trains of thought 
 until this power begins to operate. Those 
 who are born such idiots as never to shew 
 any signs of this power, shew as little any 
 .signs of regularity of thought. It seems, 
 therefoic, tliat this power is connected with 
 all regular trains of thought, and may be 
 the cause of them- 
 
 Such trains of thought discover tliem- 
 selves in children about two years of age. 
 They can then give attention to the opera- 
 tions of older children in making their 
 little houses, and ships, and other such 
 things, in imitation of the works of men. 
 'i'hey are then capable of understanding a 
 little of language, which shews both a 
 regular train of thinking, and .some degree 
 of abstraction. I think we may perceive a 
 distinction between tlie faculties of cliildrcn 
 of two or three years of age, and those of 
 the most sagacious brutes. Tliey can then 
 perceive design and regularity in the works 
 of others, especially of older children ; their 
 14.16, 417] 
 
 little minds are fired with the discovery; 
 they are eager to imitate it, and never at 
 rest till they can exhibit something of the 
 same kind. 
 
 When a child first learns by imitation 
 to do something that requires design, how 
 does he exult ! Pythagoras was not more 
 happy in the discovery of his famous theo- 
 rem. He seems then first to reflect upon 
 himself, and to swell with self-esteem. His 
 eyes sparkle. He is impatient to shew his 
 performance to all about him, and thinks 
 himself entitled to their applause. He is 
 applauded by all, and feels the same emo- 
 tion from this applause, as a Roman Con- 
 sul did from a triumph. He has now a 
 consciousness of some worth in himself. He 
 assumes a superiority over those who are 
 not so wise, and pays respect to those who 
 are wiser than himself. He attempts 
 something else, and is every day reaping 
 new laurels. 
 
 As children grow up, they are delighted 
 with tales, with childish games, with designs 
 and stratagems. Everything of this kind 
 stores the fancy with a new re^tular train of 
 thought, which becomes familiar by repeti- 
 tion, so that one part draws the whole after 
 it in the imagination. [417] 
 
 The imagination of a child, like the hand 
 of a painter, is long employed in copying 
 the works of others, before it attempts any 
 invention of its own. 
 
 The power of invention is not yet brought 
 forth ; but it is coming forward, and, like 
 the bud of a tree, is ready to burst its 
 integuments, when some accident aids its 
 eruption. 
 
 There is no power of the understanding 
 that gives so much pleasure to the owner, 
 as that of invention, whether it be employed 
 in mech.mics, in science, in the conduct of 
 life, iu poetry, in wit, or in the fine arts. 
 One who is conscious of it, acquires thereby 
 a worth and importance in his own eye 
 which he had not liefore. He looks upon 
 himself as one who formerly lived upon the 
 bounty and gratuity of others, but who has 
 now acquired some property of his own. 
 When this power begins to be felt in the 
 young mind, it has the grace of novelty 
 added to its other charms, and, like the 
 youngest child of the family, is caressed 
 beyond all the rest. 
 
 We may be sure, .hereforc, that, as soon 
 as children are conscious of this power, 
 they will exercise it iu such wa\s as are 
 suited to their age, and to the objects they 
 are employed about. 'I'his gives rise to 
 innumerabk; new associations, and regular 
 trains of thought, whii-h make the deej)er 
 inq)ression ui)on the mind, as they are its 
 exclusive property. 
 
 I am aware that tlit^ powiT of invcntiou 
 is distributed among men more unequally
 
 384 
 
 ON THE INTELLECTUAL POWERS. [essay iv. 
 
 than almost any other. When it is able to 
 produce anything that is interesting to man- 
 kind we call it genius ; a talent which is the 
 lot of very few. But there is, perliaps, a 
 lower kind or lower degree of invention that 
 is more common. However this may be, it 
 must be allowed that the power of invention 
 in those who have it, will produce many 
 new regular trains of thought ; and these 
 being expressed in works of art, in writing, 
 or iu discourse, will be copied by others. 
 [418] 
 
 Thus, I conceive the minds of children, 
 as soon as they have judgment to distin- 
 guish what is regular, orderly, and connected, 
 from a mere medley of thought, are fur- 
 nished with regular trains of thinking by 
 these means. 
 
 First and chiefly, by copying what they 
 see in the works and in the discourse of 
 others. Man is the most imitative of all 
 animals ; he not only imitates with inten- 
 tion, and purposely, what he thinks has any 
 grace or beauty, buteven without intention, 
 he is led, by a kind of instinct, which it is 
 difficult to resist, into the modes of speakini^, 
 thinking, and acting, which he has been ac- 
 customed to see in his early years. The 
 more children see of what is regular and 
 beautiful in what is presented to them, the 
 more they are led to observe and to imitate 
 it. 
 
 This is the chief part of their stock, and 
 descends to them by a kind of tradition 
 from those who came before them ; and we 
 shall find that the fancy of most men is 
 furnished from those they have conversed 
 with, as well as their religion, language, 
 and manners. 
 
 Secoii'lly, By the additions or innovations 
 that are properly their own, these will be 
 greater or less, in proportion to their study 
 and invention ; but in the bulk of mankind 
 are not very considerable- 
 
 Every profession and every rank in life, 
 has a manner of thinkhig, and turn of fancy 
 that is proper to it ; by which it is character- 
 ised in comedies and works of humour. 
 Tile bulk of men of the same nation, of the 
 same rank, and of the same occupation, are 
 cast as, it were, in the same mould. Tliis 
 mould itself changes gradually, but slowly, 
 by new inventions, by intercourse with 
 strangers, or by other accidents.* [419] 
 
 The condition of man requires a longer 
 infancy and youth than that of other ani- 
 mals ; for this reason, among others, that 
 almost every station in civil society requires 
 a multitude of regular trains of thought, to 
 
 " * Non ad rationera sed adsitniUtudiiiemcompo- 
 nimur," says Seneca; and Sihiller — 
 
 " Man— he is aye an imitative creature. 
 And lie who is the foremost leads the flock." 
 There would be no end of quotations to the same 
 eftect.— H. 
 
 be not only acquired, but to be made so 
 familiar by frequent repetition, as to pre- 
 sent themselves spontaneously when there 
 is occasion for them. 
 
 The imagination even of men of good 
 parts never serves them readily but in 
 things wherein it has been much exercised. 
 A minister of state holds a conference with 
 a foreign ambassador with no greater emo- 
 tion than a professor in a college prelects to 
 his audience. The imagination of each 
 presents to him what the occasion requires 
 to be said, and how. Let them change 
 plivces, and both would find themselves at a 
 loss. 
 
 Tiie habits which the human mind is 
 capable of acquiring by exercise are won- 
 derful in many instances ; in none more 
 wonderful than in that versatility of imagin- 
 ation which a well-bred man acquires by 
 being much exercised in the various scenes 
 of life. In the morning he visits a friend 
 in affliction. Here his imagination brings 
 forth from its store every topic of consola- 
 tion ; everything that is agreeable to the 
 laws of friendship and sympathy, and no- 
 thing that is not so. From thence he drives 
 to the minister's levee, where imagination 
 readily sugi^ests what is proper to be said 
 or replied to every man, and in what man- 
 ner, according to the degree of acquaint- 
 ance or familiarity, of rank or dependence, 
 of opposition or concurrence of interests, of 
 confidence or distrust, that is between them. 
 Nor does all this employment hinder him 
 from carrying on some design with much 
 artifice, and endeavouring to penetrate into 
 the views of others through the closest dis- 
 guises. From the levee he goes to the 
 Housp of Connnons, and speaks upon the 
 affairs of the nation ; from thence to a ball 
 or assembly, and entertains the ladies- His 
 imagination puts on the friend, the courtier, 
 the patriot, the fine gentleman, with more 
 ease than we put off one suit and put on 
 another. [420] 
 
 This is the effect of training and exer- 
 cise. For a man of equal parts and know- 
 ledge, but unaccustomed to those scenes of 
 public hfe, is quite disconcerted when first 
 brought into them. His thoughts are put 
 to flight, and he cannot rally them. 
 
 There are feats of imagination to be 
 learned by application and practice, as won- 
 derful as the feats of balancers and rope- 
 dancers, and often as useless. 
 
 When a man can make a hundred verses 
 standing on one foot, or play three or four 
 games at chess at the same time without 
 seeing the board, it is probable he hath 
 spent his life in acquiring such a feat. How- 
 ever, such unusual phsenomena shew what 
 habits of imagination may be acquired. 
 
 When such habits are acquired and per- 
 fected, they are exercised without any labo- 
 
 [418-4.20]
 
 CHAP. IV. 1 OF THE TRAIN OF THOUGHT IN THE MIND. 
 
 SPo 
 
 rious eflFort ; like the habit of playing upon 
 an instrument of music There are innu- 
 merable motions of the fingers upon the 
 stops or keys, which must be directed in 
 one particular train or succession. There 
 is only one arrana;ement of those motions 
 that is ri_'ht, while there are ten thousand 
 that are wrong, and would spoil the music. 
 The musician tliinks not in the least of the 
 arrangement of those motions ; he has a dis- 
 tinct idea of the tune, and wills to play it. 
 The motions of the fingers arrange them- 
 selves so as to answer his intention. 
 
 In like manner, when a man speaks upona 
 subject with wliich he is acquainted, there is 
 a certain arrangement ot his thoughts and 
 words necessary to make his discourse sen- 
 sible, pertinent, and grammatical. In every 
 sentence there are more rules of granmiar, 
 logic, and rhetoric that may be transgressed, 
 than there are words and letters. He 
 speaks without thinking of any of those 
 rules, and yet observes them all, as if they 
 were all in his eye. [421] 
 
 This is a habit so similar to that of a 
 player on an instrument, that I think both 
 must be got in the same way — that is, by 
 much practice, and the power of habit. 
 
 \\'hen a man speaks well and methodi- 
 cally upon a subject without study and with 
 perfect ease, I believe we may take it for 
 granted that his thoughts run in a beaten 
 track. There is a mould in his mind — 
 which has been formed by much practice, or 
 by study— for this very subject, or for some 
 other so similar and analogous that his 
 discourse falls into this mould with ease, 
 ftud takes its form from it. 
 
 Hitherto we have considered the opera- 
 tions of fancy that are either spontaneous, 
 or, at least, require no laborious effort to 
 guide and direct them, and have endeav- 
 oured to account for that degree of regu- 
 larity and arrangement which is found even 
 in them. The natural powers of judgment 
 and invention, the pleasure that always 
 attends the exercise of those powers, the 
 means we have of improving them by hni- 
 tatlon of others, and the effect of practice 
 and habits, seem to me sufficiently to 
 account for this phenomenon, without sup- 
 posing any unaccountable attractions of ideas 
 by which they arrange themselves. 
 
 But we are able to direct our thoughts in 
 a certain course, so as to perform a destined 
 task. 
 
 Kvery work of art has its model framed 
 in the imagination. Here the " Iliad" of 
 Homer, the " Kei-ublic" of Plato, the 
 " Priiicipia" of Newton, were fabi'icated. 
 Shall we believe that those works took the 
 form in which they now api)ear of them- 
 selves ? — that the sentiments, the manners, 
 and the passions arr:inKed tlieinselves at 
 once in the mind of Homer, so as to form 
 [421-4^^3] 
 
 the " Iliad ?" Was there no more effort 
 in the composition than there is in telling a 
 well-known tale, or singing a favourite 
 song ? This cannot be believed, [422] 
 
 Granting that some happy thought first 
 sugfjested the design of singing the wrath of 
 Achilles, yet, surely, it was a matter of 
 judgment and choice where the nairaion 
 should begin and where it should end. 
 
 Granting that the fertility of the poet's 
 imagination suggested a variety of rich ma- 
 terials, was not judgment necessary to select 
 what was proper, to reject what was im- 
 proper, to arrange the materials into a just 
 composition, and to adapt them to each 
 other, and to the design of the whole ? 
 
 No man can believe that Homer's ideas, 
 merely by certain sympathies and antipa- 
 thies, by certain attractions and repulsions 
 inherent in their natures, arranged them- 
 selves according to the most perfect rules of 
 epic poetry; and Newton's, according to 
 the rules of mathematical composition- 
 
 I should sooner believe that the poet, 
 after he invoked his muse, did nothing at 
 all but listen to the song of the god less. 
 Poets, indeed, and other artists, must make 
 their works appear natural; but nature is 
 the perfection of art, and tlieie can be no 
 just imitation of nature without art. When 
 the building is finished, the ruhlish, the 
 scafl'olds, the tools and engines are carried 
 out of sight ; but we know it could not have 
 been reared without them. 
 
 Thetrain of thinking, therefore, is eajable 
 of being guided and directed, much in the 
 same manner as the horse we ride. The 
 horse has his strength, his agility, and his 
 mettle in himself; he has been taught cer- 
 tain movements, and many useful habits, 
 that make him more subservient to our 
 purposes and obedient to our will ; but to 
 accomplish a journey, he must be directed 
 by the rider. 
 
 In like manner, fancy has its original 
 powers, which are very dift'erent in diflerent 
 persons ; it has likewise more regular mo- 
 tions, to which it has been trained by along 
 course of disci])liue and exercise, and by 
 which it may, c J lemi,orr, and without much 
 effort, produce things that have a consid- 
 erable degree of beauty, regularity, and 
 design. [423] 
 
 But the most perfect works of design are 
 never extemporary. Our first thoughts are 
 reviewed ; we place them at a proper dis 
 tance; examine eve.y part, anti take a 
 complex view of the whole. By our criti- 
 cal faculties, we perceive this Jiart to bo 
 rcdunilant, that deficient ; liere is a want 
 of nerves, there a want ol .Irlicacy ; this is 
 ob.scure, that too diffuse. Things are mar- 
 shalled anew, according to a second and 
 more deliberate judgment ; what was defi- 
 cient, is supplied ; what was dish)™tcd, i» 
 
 2
 
 386 
 
 ON THE INTELLECTUAL POVFERS. 
 
 [essay IV, 
 
 put in joint ; redundances are lopped off, 
 and the whole polished. 
 
 Though poets, of all artists, make the 
 highest claim to inspiration ; yet, if we be- 
 lieve Horace, a competent judge, no pro- 
 duction in that art can have merit which 
 has not cost such labour as this in the 
 birth. 
 
 " Vos O! 
 Pompilms sanguis, c:irmcn reprehendite quod non 
 Multa dies, et multa litura coercuit, atque 
 Perf'ectum decies non castigavit ad unguem." 
 
 The conclusion I would draw from all 
 that has been said upon this subject is. 
 That everything that is regular in that 
 train of thought which we call fancy or 
 imagination, from the little designs and 
 reveries of children to the grandest pi'u- 
 ductious of human genius, was originally 
 the offspring of judgment or taste, applied 
 with some effort greater or less. What 
 one person composed with art and judg- 
 ment, is imitated by another with great 
 ease. What a man himself at first com- 
 posed with pains, becomes by habit so 
 familiar as to offer itself spontaneously to 
 his fancy afterwards. But nothing that is 
 regular was ever at first conceived without 
 design, attention, and care. [424] 
 
 I shall now make a few reflections upon a 
 theory which has been applied to account 
 for tliis successive train of thought in the 
 mind. It was hinted by Mr Hobbes, but 
 has drawn more attention since it was dis- 
 tinctly explained by Mr Hume. 
 
 That author* thinks that the train of 
 thought in the mind is owing to a kind of 
 attraction which ideas have for other ideas 
 that bear certain relations to them. He 
 thinks the complex ideas — which are the 
 common subjects of our thoughts and rea- 
 .soning— are owing to the same cause. The 
 relations which produce this attraction of 
 ideas, he thinks, are these three only — to 
 wit, causation, contiguity in time or place, 
 and similitude. He asserts that these are 
 the only general principles that unite ideas. 
 And having, in another place, occasion to 
 take notice of contrariety as a principle of 
 connection among ideas, in order to recon- 
 cile this to his system, he tells us gravely, 
 that contrariety may perhaps be considered 
 as a mixture of causation and resemblance. 
 That ideas which have any of these three 
 relations do mutually attract each other, so 
 that one of them being presented to the 
 fancy, the other is drawn along with it — 
 this he seems to think an original property 
 «)f the mind, or rather of the ideas, and 
 tlierefore inexplicable. -f 
 
 * He should have said thii author, for Hume is 
 referred to.^H. 
 
 t S e above, p. S9I, b, note f. The history of the 
 doctrine of Association has never yet been at all 
 adequately developed. Some of the most remark. 
 
 First, I observe, with regard to tliis 
 theory, that, although it is true that the 
 thought of any object is apt to lead us to 
 the thought of its cause or effect, of things 
 contiguous to it in time or place, or of 
 things resembling it, yet this enumeration 
 of the relations of things which are apt to 
 lead us from one object to another, is very 
 inaccurate. 
 
 The enumeration is too large upon his 
 own principles ; but it is by far too scanty in 
 reality. Causation, according to his philo- 
 sophy, implies notliing more than a con- 
 stant conjunction observed between the 
 cause and the effect, and, therefore, conti- 
 guity must include causation, and his three 
 principles of attraction are reduced to two. 
 [425] 
 
 But when we take all the three, the enu- 
 meration is, in reality, very incomplete. 
 Every relation of things has a tendency, 
 more or less, to lead the thought, in a 
 thinking mind, from one to the other ; and 
 not only every relation, but every kind of 
 contrariety and opposition. What Mr 
 Hume says — that contrariety may perhaps 
 be considered as a mi.xture " of causation 
 and resemblance" — I can as little compre- 
 hend as if he had said that figure may per- 
 haps be considered as a mixture of colour 
 and sound. 
 
 Our thoughts pass easily from the end 
 to the means ; from any truth to the evi- 
 dence on which it is founded, the conse- 
 quences that may be drawn from it, or the 
 u.se that may be made of it. From a part 
 we are easily led to think of the whole, from 
 a subject to its rjualities, or from things 
 related to the relation. Such transitions in 
 thinking nmst have been made thousands 
 of times by every man who thinks and 
 reasons, and thereby become, as it were, 
 beaten tracks for the imagination. 
 
 Not only the relations of objects to each 
 other influence our train of thinking, but 
 the relation they bear to the present tem- 
 per and disposition of the mind ; their re- 
 lation to the habits we have acquired, 
 whether moral or intellectual ; to the com- 
 pany we have kept, and to the business in 
 which we have been chiefly employed. The 
 same event will suggest very different re- 
 flections to different person.", and to the 
 same person at different times, according 
 as he is in good or bad humour, as he is 
 lively or dull, angry or pleased, melanclioly 
 or cheerful. 
 
 Lord Karnes, in his " Elements of Criti- 
 cism," and Dr Gerard, in his " Essay on 
 Genius," have given a much fuller and 
 juster enumeration of the causes that in- 
 fluence our train of thinking, and I have 
 
 able speculations on this matter are wholly unknown. 
 Of these I can, at present, sav nothing. — H. See 
 Notes D * *, D • * *. ' [424, 425]
 
 CHAP. IV.] OF THE TRAIX OF THOUGHT IN THE MIND. 
 
 387 
 
 nothing to add to what they have said on 
 this subject. 
 
 Secondli/, Let us consider how far this 
 attraction of ideas must be resolved into 
 original ijualities of human nature. [426] 
 
 I believe the original principles of the 
 mind, of which we can give no account but 
 that such is our constitution, are more in 
 number than is commonly thouglit. But 
 we ought not to multiply them without 
 necessity. 
 
 That trains of thinking, which, by fre- 
 quent repetition, have become familiar, 
 should spontaneously offer themselves to 
 our fancy, seems to require no other origi- 
 nal quality but the power of habit.* 
 
 In all rational thinking, and in all rational 
 discourse, whether serious or facetious, the 
 thought must have some relation to what 
 went before. Every man, therefore, from 
 the dawn of reason, nmst have been accus- 
 tomed to a train of related objects. These 
 please the understanding, and, by custom, 
 become like beaten tracks which invite the 
 traveller. 
 
 As far as it is in our power to give a 
 direction to our thoughts, which it is un- 
 doubtedly in a great degree, they will be 
 directed by the active principles common 
 to men — by our appetites, our passions, our 
 affections, our reason, and conscience. And 
 that the trains of thinking in our minds are 
 chiefly governed by these, according as one 
 or another ]irevails at the time, every man 
 will find in his experience. 
 
 If the mind is at any time vacant from 
 every passion and desire, there are still 
 some objects that are more acceptable to 
 us than others. The facetious man is 
 pleased with surprising similitudes or con- 
 trasts ; the philosopher with the relations 
 of tilings that are subservient to reasoning ; 
 the merchant with what tends to profit; 
 and the politician with what may mend the 
 state. 
 
 A good writer of comedy or romance can 
 feign a train of thinking for any of the per- 
 sons of liis fable, whicii aiijjoars very natu- 
 ral, and is approved by the best judges. 
 Now, what is it that entitles such a fiction 
 to ajiprobation ? Is it that the autlior has 
 given a nice attention to the relations of 
 causation, contiguity, and similitude in tlie 
 ideas? [427] This surely is the least 
 part of its merit. But the ciiief part con- 
 sists in this, that it corresponds perfectly 
 with the general character, tiie rank, tlie 
 habits, the present situation and passions of 
 the person. If this be a just way of judging 
 in criticism, it follows necessarily, that tiic 
 circumstances last mentioned have tlie cliief 
 influence in suggesting our trains of thouglit. 
 
 * We can as well explain Habit by Aitociatlon, 
 «« A»«ociatinn by Ila! il— H. 
 
 It cannot be denied, that the state of the 
 body has an influence upon our imagination, 
 according as a man is sober or drunk, ivs 
 he is fatigued or refreshed. Crudities and 
 indigestion are said to give uneasy dreams, 
 and have probably a like effect upon the 
 waking thoughts. Opium gives to some 
 persons pleasing dreams and pleasing im- 
 aginations when awiike, and to others such 
 as are horrible and distressing. 
 
 These influences of the body upon the 
 mind can only be known by experience, and 
 I believe we can give no account of them. 
 
 Nor can we, perhaps, give any reason whj 
 we must think without ceasing while we are 
 awake. I believe we are likewise origi- 
 nally disposed, in imagination, to pass from 
 any one object of thought to others that are 
 contiguous to it in time or place. This, I 
 think, may be observed in brutes and in 
 idiots, as well as in children, before any 
 habit can be acquired that might account 
 for it. The sight of an object is apt to 
 suggest to the imagination what has been 
 ' seen or felt in conjunction with it, even 
 when the memory of that conjunction is 
 gone. 
 
 Such conjunctions of things influence not 
 only the imagination, but the belief and the 
 passions, especially in children and in 
 brutes ; and perliaps all that we call memory 
 in brutes is something of this kind. 
 
 They expect events in the same order and 
 succession in which they happened before ; 
 and by this expectation, their actions and 
 passions, as well as their thoughts, are re- 
 gulated. [428] A horse takes fright at 
 the place where some oljject frighted him 
 before. We are apt to conclude from this 
 that lie remembers the former accident. 
 But perhaps there is only an association 
 formed in his mind between the (ilace and 
 the passion of fear, without any distinct 
 remembrance. 
 
 I\Ir Locke has given us a very good 
 chapter upon the association of ideas ; and 
 by the examples he has given to illustrate 
 this doctrine, 1 tliink it a])pears that very 
 strong associations may be formed at once — 
 not of ideas to ideas only, but of ideas to 
 passions and emotions ; atid that strong as- 
 sociations are never formed at once, but 
 when accompanied by some strong passion 
 or emotion. I believe this nmst be resolved 
 into the constitution of our nature. 
 
 Mr Hume's opinion — that the complex 
 ideas, which are tlie coiiiiiion objects of 
 discourseaiid reasoning, are forniid bythoso 
 original attractions of ideas to which ho 
 aKcrilx.'s tlie train of tliduglits in the iniiid — 
 will come under consideration in ttiiotlicr 
 place. 
 
 To put an end to our remarks upon tliis 
 tlieory of i\lr Hume, I think he has real 
 merit in bringing this curious suliject under 
 
 'i c U
 
 388 
 
 ON THE INTELLECTUAL POWERS. 
 
 [essay IV. 
 
 thft view of philosophers, and carrying it a 
 certain length. But I see nothing in this 
 the )ry that should hinder us to conclude, 
 that everything in the trains of our thought, 
 which bears the marks of judgment and 
 reason, has been the product of judgment 
 and reason previously exercised, either by 
 the person himself, at that or some former 
 time, or by some other person. The at- 
 traction of ideas will be the same in a man's 
 second thoughts upon any subject as in his 
 first. Or, if some change in his circum- 
 stances, or in the objects about him, should 
 make any change in the attractions of his 
 ideas, it is an equal chance whether the 
 second be better than the first, or whether 
 they be worse. 'But it is certain that 
 every man of judgment and taste will, upon 
 a review, correct that train of thought which 
 first presented itself If the attractions of 
 ideas are the sole causes of the regular 
 arrangement of thought in the fancy, there 
 is no Hse for judgment or taste in any com- 
 position, nor indeed any room for their 
 operation. [429 J 
 
 There are other reflections, of a more 
 practical nature and of higher importance, 
 to which this subject leads. 
 
 I believe it will be allowed by every man, 
 that our happiness or misery in life, that 
 our improvement in any art or sciencewhich 
 we profess, and that our improvement in 
 real virtue and goodness, depend in a very 
 great degree on the train of thinking that 
 occupies the mind both in our vacant and 
 in ouF more svrious hours. As far, there- 
 fore, as the direction of our thoughts is in 
 our power, (and that it is so in a great 
 measure, cannot be doubted) it is of the last 
 importance to give them tliat direction which 
 is most subservient to those valuable pur- 
 poses. 
 
 AVhat employment can he have worthy 
 of a man, whose imagination is occupied 
 only about things low and base, and grovels 
 in a narrow field of mean, unanimating, and 
 uninteresting objects, insensible to those 
 finer and more delicate sentiments, and 
 blind to those more enlarged and nobler 
 views which elevate the soul, and make it 
 conscious of its dignity. 
 
 How different from him whose imagina- 
 tion, like an eagle in her flight, takes a wide 
 prospect, and observes whatever it presents, 
 that is new or beautiful, grand or important ; 
 whose rapid wing varies the scene every 
 moment, carrying him sometimes through 
 the fairy regions of wit and fancy, some- 
 
 times through the more regular and sober 
 walks of science and philosophy 1 
 
 The various objects which he surveys, 
 according to their different degrees of beauty 
 and dignity, raise in him the lively and 
 agreeable emotions of taste. Illustrious 
 human characters, as they pass in review, 
 clothed with their moral qualities, touch his 
 heart still more dee])ly. They not only 
 awaken the sense of beauty, but excite the 
 sentiment of approbation, and kindle the 
 glow of virtue. 
 
 While he views what is truly great and 
 glorious in human conduct, his soul catches 
 the divine flame, and burns with desire to 
 emulate what it admires. [430] 
 
 The human imagination is an ample 
 theatre, upon which everythir.-g in human 
 life, good or bad, great or mean, laudable 
 or base, is acted. 
 
 In children, and in some frivolous minds, 
 it is a mere toy-shop. And in some, who 
 exercise their memory without their judg- 
 ment, its furniture is made up of old scraps 
 of knowledge, that are thread-bare and 
 worn out. 
 
 In some, this theatre is often occupied by 
 ghastly superstition, with all her train of 
 Gorgons, and Hydras, and Chimeeras dire. 
 Sometimes it is haunted with all the infernal 
 demons, and made the forge of plots, and 
 rapine, and murder. Here everything that 
 is black and detestable is first contrived, and 
 a thousand wicked designs conceived that 
 are never executed. Here, too, the furies 
 act their part, taking a severe though secret 
 vengeance upon the self-condemned criminal. 
 
 How happy is that mind in which the light 
 of real knowledge dispels the phantoms of 
 superstition ; in which the belief and rever- 
 ence of a perfect all-governing mind casts 
 out all fear but the fear of acting wrong ; 
 in which serenity and cheerfulness, inno- 
 cence, humanity, and candour, guard the im- 
 agination against the entrance of every un- 
 hallowed intruder, and invite more.amiable 
 and- worthier guests to dwell ! 
 
 There shall the Muses, the Graces, and 
 the Virtues fix their abode ; for everything 
 that is great and worthy in human conduct 
 must have been conceived in the imagina- 
 tion before it was brought into act- And 
 many great and pood designs have been 
 formed there, which, for want of power and 
 opportunity, have proved abortive. 
 
 The man whose imagination is occupied 
 by these guests, must be wise ; he must be 
 good ; and he must be happy. [431 ] 
 
 [4-29-431]
 
 CHAP. l.J 
 
 OF GENERAL WORDS. 
 
 389 
 
 ESSAY V. 
 
 OF ABSTRACTION. 
 
 CHAPTER I. 
 
 OF GENERAL WORDS. 
 
 The words we use in language are either 
 general words or proper names. Proper 
 names are intended to signify one individual 
 only. Such are the names of men, king- 
 doms, provinces, cities, rivers, and of every 
 other creature of God, or work of man, 
 which we choose to distinguish from all 
 others of the kind, by a name appropriated 
 to it. All the other words of language are 
 general words, not appropriated to signify 
 any one individual thing, but equally related 
 to many. 
 
 Under general words, therefore, I com- 
 prehend not only those which logicians call 
 general terms — that is, such general words 
 as may make the subject or the predicate 
 of a proposition, but likewise their auxiliaries 
 or accessories, as the learned Mr Harris 
 calls them ; such as |)repositions, conjunc- 
 tions, articles, which are^all general words, 
 though they cannot properly be called gejie- 
 ral terms. 
 
 In every language, rude or polished, 
 general words make the greatest part, and 
 proper names the least. Grammarians 
 have reduced all words to eight or nine 
 classes, wliich are called parts of sjieech. 
 Of these there is only one — to wit, that of 
 nouns — wherein proper names are found. 
 [432] Alt jiiououfis, vrLs, pnrlirip/es, ad- 
 vrbs, articL s, prepositions, conjuncti ins, and 
 iii'eij'cti.ni, are general word.s. Of nouns, 
 all adjec'.tvns are general words, and the 
 greater part of sulistanlivPs. Every .sub- 
 stantive that has a plural number, is a gene- 
 ral word ; for no projier name can have a 
 plural number, because it signifies only one 
 individual. In all the fifteen books of 
 Euclid's Elements, there is not one word 
 that is not general ; and the same may be 
 said of many large volumes. 
 
 At the same time, it must be acknowledged, 
 that all tlie objects we perceive are individ- 
 uals. Every object of sense, of memory, 
 or of consciousness, is an individual object. 
 All tlie good tilings we enjoy or desire, and 
 all the evils we feel or fear, must come from 
 individuals ; and I think we may venture to 
 say, that every creature which Cied h.'is made, 
 in the heavens above, or in the earth be- 
 
 neath, or in the waters under the earth, is 
 an individual.* 
 
 How comes it to pass, then, that, in all 
 languages, general words make the greatest 
 part of the language, and proper names but 
 a very small and inconsiderable part of it. 
 
 This seemingly strange plia;nomenon may, 
 I think, be easily accounted for by the fol- 
 lowing observations : — 
 
 First, Though there be a few individuals 
 that are obvious to the notice of all men, 
 and, therefore, have proper names in all 
 languages — such as the sun and moon, the 
 earth and sea — yet the greatest part of the 
 things to which we think fit to give proper 
 names, are .local ; known perhaps to a vil- 
 lage or to a neighbourhood, but unknown to 
 the greater part of those who speak tho 
 same language, and to all the rest of man- 
 kind. The names of such things being con- 
 fined to a corner, and having no names 
 answering to them in other languages, are 
 not .iccounted a part of the language, any 
 more than the customs of a particular ham- 
 let are accounted part of the law of the 
 nation. [433] 
 
 For this reason, there are but few proper 
 names that belong to a language. It is 
 next to be considered wliy there must be 
 many general words in every language. 
 
 Secondly. It may be observed, that every 
 individual object that falls within our view 
 has various attributes ; and it is by them 
 that it becomes useful or hurtful to us. 
 We know not the essence of any individual 
 object ; all the knowledge we can attain of 
 it, is the knowledge of its attributes — its 
 quantity, its various qualities, its various 
 relations to other tliuigs, its place, its 
 situation, and motions. It is by such attri- 
 butes of things only lliat we can coiiimuni- 
 cate our knowledge of them to otiiers. By 
 their attributes, our hopes or fears for them 
 are regulated ; and it is only by attention 
 to their attributes tliat we can make them 
 subservient to our end.s ; and therefore wo 
 give names to such attributes. 
 
 Now, all attributes must, from their 
 nature, be e.tpressed by general words, and 
 are .so expressed in all languag<'s. In the 
 ancient philosophy, attributes in general 
 were called by two names which express 
 
 * Thii nncthiui liai wcllrxprciied : — " Omnr. quoit 
 at, fo rfuod cut, tinijiilarc ft," — 1 1.
 
 3U0 
 
 ON THE INTELLECTUAL POWEIIS. 
 
 ["essay 
 
 their nature. Tiiey were called uuiversa/s, 
 because they might belong equally to many 
 individuals, and are not confined to one. 
 They were also called predicables, because 
 whatever is predicated, that is, affirmed or 
 denied of one subject, may be of more, and 
 therefore is an universal, and expressed by 
 a general word. A predicable therefore 
 signifies the same thing as an attribute, with 
 this difference only, that the fir»t is Latin, 
 the last English.* The attributes we find 
 either in the creatures of God or in the 
 works of men, are common to many indi- 
 duals. We either find it to be so, or i)re- 
 sume it may be so, and give them the same 
 name in every subject to which they belong. 
 
 There are not only attributes belonging 
 to individual subjects, but there are likewise 
 attributes of attributes, which may be called 
 6econdary attributes. Most attributes are 
 capable of different degrees and different 
 modifications, which must be expressed by 
 general words. [434] 
 
 Thus it is an attribute of many bodies to 
 oe moved ; but motion may be in an endless 
 variety of directions. It may be quick or 
 slow, rectilineal or curviliueal ; it may be 
 equable, or accelerated, or retarded. 
 
 As all attributes, therefore, whether pri- 
 mary or secondary, are expressed by general 
 words, it ioUows that, in every proposition 
 we express in language, what is affirmed or 
 denied of the subject of the proposition must 
 be expressed by general words : and that 
 the subject of the proposition may often be 
 a general word, will appear from the next 
 observation. 
 
 Thirdly, The same faculties by which we 
 distinguish the diff'erent attributes belong- 
 ing to the same subject, and give names 
 to them, enable us likewise to observe, 
 that many subjects agree in certain attri- 
 butes while they differ in others. By this 
 means we are enabled to reduce individuals 
 which are infinite, to a limited number of 
 classes, which are called kinds and sorts ; 
 and, in the scholastic language, genera and 
 species. 
 
 Observing many individuals to agree in 
 certain attributes, we refer them all to one 
 class, and give a name to the class. This 
 name comprehends in its signification not 
 one attribute only, but all the attributes 
 which distinguish that class; and by affirm- 
 ing this name of any individual, we affirm 
 it to have all the attributes which charac- 
 terise the class : thus men, dogs, horses, 
 elephants, are so many diff'erent classes of 
 animals. In like manner we marshal other 
 substances, vegetable and inanimate, into 
 classes. 
 
 * Tliey are bo.h Latin, or both English. The only 
 difference is, that the one is oi technical, the other 
 of popular application, and that the former expresses 
 as potential wliat the latter iioes as actual. — H. 
 
 Nor is it only substances that we thus 
 form into classes. We do the same with 
 regard to qualities, relations, actions, affec- 
 tions, passions, and all other things. 
 
 When a class is very large, it is divided 
 into subordinate classes in the same man- 
 ner. [4;i5] The higher class is called a 
 genus or kind : the lower a species or stjrt 
 of the higher. Sometimes a species is still 
 subdivided into subordinate species ; and 
 this subdivision is carried on as far as is 
 foundconvenientforthe purpose of language, 
 or for the improvement of knowledge. 
 
 In this distribution of things into genera 
 and species, it is evident that the name of 
 the species comprehends more attributes 
 than the name of the genus. The species 
 comprehends all that is in the genus, and 
 those attributes likewise which distinguish 
 that species from others belonging to the 
 same genus ; and the more subdivisions we 
 make, the names of the lower become still 
 the more comprehensive in their significa- 
 tion, but the less extensive in their appli- 
 cation to individuals. 
 
 Hence it is an axiom in logic — that the 
 more extensive any general term is, it is the 
 less comprehensive ; and, on the contrary, 
 the more comprehensive, the less extensive. 
 Thus, in the following series of subordinate 
 general terms — Animal — Man — French- 
 man — Parisian, every subsequent term com- 
 prehends in its signification all that Ls in 
 the preceding, and something more ; and 
 every antecedent term extends to more 
 individuals than the subsequent. 
 
 Such divisions and subdivisions of things 
 into genera and spec es with general names, 
 are not confined to the learned and polished 
 languages ; they are found in those of the 
 rudest tribes of mankind. From which we 
 learn, that the invention and the use of 
 general words, both to signify the attributes 
 of things, and to signify the genera and 
 species of things, is not a subtile invention 
 of philosophers, but an operation which all 
 men perform by the light of common sense. 
 Philosophers may speculate about this ope- 
 ration, and reduce it to canons and aphor- 
 isms ; but men of common understanding, 
 without knowing anything of the philosophy 
 of it, can put it in practice, in like manner 
 as they can see objecfs, and make good use 
 of their eyes, although they know nothing 
 of the structure of the eye, or of the theory 
 of vision. [4'i()] 
 
 Every genus, and every species of things, 
 may be either the subject or the predicate 
 of a proposition — nay, of innumerable pro- 
 positions ; for every attribute common to 
 the genus or species may be affirmed of it ; 
 and the genus may be affirmed of every 
 species, and both genus and species of every 
 individual to which it extends. 
 
 Thus, of man it maybe affirmed, that lie 
 
 [t34-43ti]
 
 CHAP. 11.] 
 
 OF GENERAL CONCEPTIONS. 
 
 391 
 
 is an animal made up of body and mind ; 
 that he is of few davs, and full of trouble ; 
 that he is capable of various improvements 
 in arts, in knowledge, and in virtue. In a 
 ■word, everything common to the species 
 may be affirmed of man ; and of all such 
 propositions, which are innumerable, man 
 is the subject. 
 
 Again, of every nation and tribe, and of 
 every uidividual of the human race that is, 
 or was, or shall be, it may be affirmed that 
 they are men. In all such propositions, 
 which are innumerable, man is the predi- 
 cate of the proposition. 
 
 We observed above an extension and a 
 comprehension in general terms ; and that, 
 in any subdivision of things, the name of 
 the lowest species is most comprehensive, 
 and that of the highest genus most exten- 
 sive. I would now observe, that, by means 
 of such general terms, there is also an ex- 
 tension and compreht-nsion of propositions, 
 which is one of the noblest powers of lan- 
 guage, and fits it for expressing, with great 
 ease and expedition, the highest attainments 
 in knowledge, of which the human under- 
 standing is capable. 
 
 When the predicate is a. (/etiiia or a speciis, 
 the proposition is more or less comprehen- 
 sive, according as the predicate is. Thus, 
 when I say that this seal is gold, by this 
 single proposition I affirm of it all the pro- 
 perties which that metal is known to have. 
 When I say of any man that he is a 
 mathematician, this appellation compre- 
 hends all the attributes that belong to 
 liiui as an animal, as a man, and as one 
 who has studied mathematics. When I 
 say that the orbit of the planet Mercury 
 is an ellipsis, I thereby affirm of that 
 orbit all the properties which Apoilonius 
 and other geometricians have discovered, 
 or may discover, of that species of figure. 
 [437] 
 
 Again, when the subject of a proposition 
 is a genus or a xpecien, the proposition is 
 more or less extensive, according as the 
 subject is. Thus, when I am taught that 
 the three angles of a plane triangle are 
 equal to two right angles, this properly ex- 
 tends to every species of plane triangle, and 
 to every individual plane triangle tliat did, 
 or does, or can exist. 
 
 It is by means of such extensive and 
 comprehensive propositions, that human 
 knowledge is condensed, as it were, into a 
 size adajited to the cajiacity of the human 
 mind, with great addition to its beauty, 
 and without any diminution of its dibtinct- 
 ness and perspicuity. 
 
 General propositions in science may lie 
 compared to tiie seed of a plant, which, 
 according to some jiliil(i'ro[iiitrH, lias not 
 only the whole future ])hiHt incio.sed within 
 it, but the seeds fif tiiat plant, ami tlic |il:iiit.s 
 
 that shall spring from them through all 
 future generations. 
 
 But the similitude falls short in this re- 
 spect, that time and accidents, not in our 
 power, must concur to disclose the contents 
 of the seed, and bring them into our view ; 
 whereas the contents of a general proposi- 
 tion may be brought forth, ripened, and 
 exposed to view at our pleasure, and in an 
 instant. 
 
 Thus the wisdom of ages, and the most 
 sublime theorems of science, may be laid 
 up, like an Iliad in a nut-shell, and trans- 
 mitted to future generations. And this 
 noble purpose of language can only be ac- 
 complished by means of general words 
 annexed to the divisions aad subdivisions of 
 things. [438] 
 
 What has been said in this chapter, I 
 think, is sufficient to shew that there can be 
 no language, not so much as a single pro- 
 position, without general words ; that they 
 must make the greatest part of every lan- 
 guage ; and that it is by them only that 
 language is fitted to express, with wonder- 
 ful ease and expedition, all the treasures 
 of human wisdom and knowledge. 
 
 CHAPTER II. 
 
 OF GENERAL CONCEPTIONS. 
 
 As general words are so necessary in 
 language, it is natural to conclude that there 
 must be general conceptions, of which they 
 are the signs. 
 
 Words are empty sounds when they do 
 not signify the thoughts of the speaker; 
 and it is only from their signification that 
 they are denominated geiu '*1. Every word 
 that is spoken, considered merely as a sound, 
 Ls an individual sound. And it can only be 
 called a general word, because that which it 
 signifies is general. Now, that which it 
 signifies, is conceived by the mind both of 
 the speaker and hearer, if the word have a 
 distinct meaning, and be distinctly under- 
 stood. It is, therefore, impossible that 
 words can have a general signification, un- 
 less there be conceptions in the mind of 
 the speaker and of the hearer, of things 
 that are general. It is to such that I give 
 the name of general conceptions ; and it 
 ouglit to be oliserved, that tliey take this 
 denomination, not from the act of the mind 
 in conceiving, which is an individual act, 
 but from the object or thing conceived, 
 which is general. 
 
 We are, therefore, hero to consider 
 whether we have such general conceiitions, 
 and how they arc fdrmed. | l.'l!) ) 
 
 'J"o ht'gin witii the ciinccplion.'^ e.\prc.^hed 
 by general Ifrms — that is, by such grntraj 
 words a.s m:i_\ lie llir suliji<'t i>r llir prrdi-
 
 392 
 
 ON THE INTELLECTUAL POWERS. 
 
 [essay v. 
 
 cate of a proposition. They are either 
 attributes of things, or they are genera or 
 sprcies of tilings. 
 
 It is evident, with respect to all the indi- 
 viduals we are acquainted with that we have 
 a more clear and distinct conception of their 
 attributes than of the subject to which those 
 attributes belong. 
 
 Take, for instance, any individual body 
 we have access to know — what conception do 
 we form of it ? Everyman may know this 
 from his consciousness. He will find that 
 he conceives it as a thing that has length, 
 breadth, and thickness, such a figure and 
 such a colour ; that it is hard, or soft, or 
 fluid ; that it has such qualities, and is fit 
 for such purposes. If it is a vegetable, he 
 may know where it grew, what is the form 
 of its leaves, and flower, and seed. If an 
 animal, what are its natural instincts, its 
 manner of life, and of rearing its young. 
 Of these attributes, belonging to this indi- 
 vidual and numberless others, he may 
 surely have a distinct conception ; and he 
 will find words in language by which he can 
 clearly and distinctly express each of them. 
 
 If we consider, in like manner, the con- 
 ception we form of any individual person of 
 our acquaintance, we shall find it to be made 
 up of various attributes, which we ascribe to 
 him ; such as, that he is the son of such a 
 man, the brother of such another ; that he 
 has such an employment or otriee ; has such 
 a fortune ; that he is tall or short, well or 
 ill made, comely or ill favoured, young or 
 old, married or unmarried ; to this we may 
 add his temper, his character, his abilities, 
 and perhaps some anecdotes of his history. 
 
 Such is the conception we form of indi- 
 vidual persons of our acquaintance. By 
 such attributes we describe them to those 
 who know them not ; and by such attri- 
 butes historians give us a conception of the 
 personages of former times. Nor is it pos- 
 sible to do it in any other way [440] 
 
 All the distinct knowledge we have or 
 can attain of any individual is the know- 
 ledge of its attributes; for we know not 
 the essence of any individual. This seems 
 to be beyond the reach of the human facul- 
 ties. 
 
 Now, every attribute is what the ancients 
 called an universal. It is, or may be, com- 
 mon to various individuals. There is no 
 attribute belonging to any creature of God 
 which may not belong to others ; and, on 
 this account, attributes, in all languages, are 
 expressed by general words. 
 
 It appears, likewise, from every man's 
 experience, that he may have as clear and 
 distinct a conception of such attributes as 
 we have named, and of innumerable others, 
 as he can have of any individual to which 
 tiiey belong. 
 
 Indeed, the attributes of individuals is all 
 
 that we distinctly conceive about them. It 
 is true, we conceive a subject to which the 
 attributes belong ; but of this subject, when 
 its attributes are set aside, we have but an 
 obscure and relative* conception, whether it 
 be body or mind. 
 
 This was before observed with regard to 
 bodies. Essay II. chap. 19, [p. 1122] to 
 which we refer ; and it is no less evident 
 with regard to minds. What is it we call a 
 mind ? It is a thinking, iiitelligent, active 
 being. Granting that thinking, intelli- 
 gence, and activity, are attributes of mind, 
 I want to know what the thing or being is 
 to which these attributes belong ? To this 
 question I can find no satisfying answer. 
 The attributes of mind, and particularly its 
 operations, we know clearly ; but of the 
 thing itself we have only an obscure no- 
 tion. [441] 
 
 Nature teaches us that thinking and 
 reasoning are attributes, which cannot exist 
 without a subject ; but of that subject I be- 
 lieve the best notion we can form implies 
 little more than that it is the subject of such 
 attributes. 
 
 Whether other created beings may have 
 the knowledge of the real essence of created 
 things, so as to be able to deduce their at- 
 tributes from their essence and constitution, 
 or whether this be the prerogative of him 
 who made them, we cannot tell ; but it is 
 a knowledge which seems to be quite be- 
 yond the reach of tlie human faculties. 
 
 We know the essence of a triangle, and 
 from that essence can deduce its properties. 
 It is an universal, and might have been 
 conceived by the human mind though no 
 individual triangle had ever existed. It has 
 only what Mr Locke calls a nominal essence, 
 which is expressed in its definition. But 
 evervthing'that exists has a real essence, 
 which is above our comprehension ; and, 
 therefore, we cannot deduce its properties 
 or attributes from its nature, as we do in 
 the triangle. We must take a contrary 
 road in the knowledge of God's works, and 
 satisfy ourselves with their attributes as 
 facts, and with the g-eneral conviction that 
 there is a subject to which those attributes 
 belong. 
 
 Enough, I think, has been said, to shew, 
 not only that we may have clear and dis- 
 tinct conceptions of attributes, but that 
 they are the only things, with regard to 
 individuals, of which we have a clear and 
 distinct conception. 
 
 The other class of general terms are those 
 that signify the f/m/'ra and species into 
 which we divide and subdivide things. Anr'j 
 if we be able to form distinct conceptions of 
 attributes, it cannot surely be denied that 
 we mny have distinct conceptions oi genera 
 
 * See above, p. 322, note.— H. 
 
 [140, 441]
 
 CHAP. 
 
 "] 
 
 OF GENERAL CONCEPTIONS. 
 
 393 
 
 and sjitiries ; because they are only collec- 
 tions of attributes wliich we conceive to 
 exist in a subject, and to which we give a 
 general name. [442] If the attributes 
 comprehended under that general name be 
 distinctly conceived, the thing meant by the 
 name must be distinctly conceived. And 
 the name may justly be attributed to every 
 individual which lias those attriluites. 
 
 Thus, I conceive distinctly what it is to 
 have wings, to be covered with feathers, to 
 lay eggs. Suppose then that we give the 
 name of bird to every animal that has these 
 three attributes. Here undoubtedly my 
 conception of a bird is as distinct as my 
 notion of the attributes which are common 
 to this species : and, if this be admitted to 
 be the definition of a bird, tliere is nothing 
 I conceive more distinctly. If I had never 
 seen a bird, and can but be made to under- 
 stand the definition, I can easily apply it to 
 every individual of the species, without 
 danger of mistake. 
 
 When thinss are divided and subdivided 
 by men of science, and names given to the 
 genera and species, those names are defined. 
 Thus, the genera and species of plants, and 
 of other natural bodies, are accurately de- 
 fined by the writers in tlie vaiious branches 
 of natural history ; so that, to all future 
 generations, the definition will convey a dis- 
 tinct notion of the genus or species defined. 
 
 There are, without doubt, many words 
 signifying genera and species of things, 
 which have a meaning somewhat vague and 
 indistinct ; so that those who speak the 
 same language do not always use them in 
 the same sense. But, if we attend to the 
 cause of this indistinctness, we shall find 
 that it is not owing to their being general 
 terms, but to this, that there is no defini- 
 tion of them that lias authority- 'i'lieir 
 meaning, therefore, has not been learned 
 by a definition, but by a kind of induction, 
 by observing to what individuals they are 
 apiilied by tliose who un<lerstand the lan- 
 guage. \V'e learn l)y habit to use them as 
 we see others do, even when we have not a 
 precise meaning annexed to them. Ainan 
 may know that to certain individuals they 
 may be applied with propriety ; but whether 
 they can be applied to certain other indivi- 
 duals, he may be uncertain, either ironi 
 want of good authorities, or from having 
 contrary authorities, which leave him in 
 doubt. ' [44:<] 
 
 Thus, a man may know tiiat, wlien lie 
 applies the name of beast to a lion or a 
 tiger, and the name of bird to an eagle or 
 a turkey, he speaks jiroperly. lint wliether 
 a bat be a bird or a beast, lu^ may be uncer- 
 tain. If there was any accurali; iiefiniti<in 
 of a beast ami of a bird, tliat was of sufii- 
 ciont authority, he could be at no 1oh«. 
 
 It is Haid to have been sometimes n mal- 
 1^2 Ui] 
 
 ter of dispute, with regard to a monstrous 
 birth of a woman, whether it was a man or 
 not. Although this be, in reality, a ques- 
 tion about the meaning of a word, it in:iy 
 be of importance, on account of the privi- 
 leges whioli laws have annexed to the human 
 character. To make sruch laws perfectly 
 precise, the definition of a man would be 
 necessary, which 1 believe legislators have 
 seldom or never thought fit to give. It is, 
 indeed, very difficult to fix a definition of 
 so common a word ; and tlie cases wherein 
 it would be of any use so rarely occur, that 
 perhaps it may be better, when they do 
 occur, to leave them to the determination 
 of a judge or of a jury, than to give a defi- 
 nition, which might be attended with un- 
 foreseen consequences. 
 
 A genus or species, being a collection of 
 attributes conceived to exist in one subject, 
 a definition is the only way to prevent any 
 addition or diminution of its ingredients in 
 the conception of difi'erent persons ; and 
 when there is no definition that can be 
 appealed to as a standard, the name will 
 hardly retain the most perfect precision in 
 its signification. 
 
 From what has been said, X conceive it 
 is evident that the words Which signify 
 genera and species of things have often as 
 precise and definite a signification as any 
 wnrds whatsoever; and that, when it is 
 otherwise, their want of ])recisi()n is not 
 owing to their being general words, but to 
 other causes. [444] 
 
 Having shewn that we may have a per- 
 fectly clear and distinct conception of the 
 meaning of general terms, we may, I think, 
 take it for granted, that the same may be 
 said of other general words, such as prepo- 
 sitions, conjunctions, articles. Jly desi^in 
 at present being only to shew that we have 
 general concejjtions no less clear and dis- 
 tinct than those of individuals, it is sufficient 
 for this purpose, if this appears with regard 
 to the conceptions expressed by general 
 terms. To conceive the meaning of a 
 general word, and to conceive that which it 
 signifies, is the same thing. Wo conceive 
 distinctly the meaning of general terms, 
 therefore we conceive distinctly that which 
 they signify. But such terms do not sig- 
 nify any individual, but what is connnoii to 
 many individuals ; therefore, we have a 
 distiiict concci>ti(in of things common to 
 many individuals—that is, \se have distinct 
 general concepti(uis. 
 
 We must here beware of the ambiguity 
 of the word coHir/ilidu, which Homi'times 
 signifies the act of the mind in conceiving, 
 sometimes the thing conceived, which is the 
 oiiject of that act." If tlio word be taken 
 
 *' riiit ia«t liliouM lie callcil Concfpt, whirh »ii» n 
 icrm 111 im- wilh tin- old IiikIhIi |ihil<miililiiTii.- II.
 
 394 
 
 ON THE INTELLECTUAL POWERS. 
 
 [kssay v. 
 
 in the first sense, I acknowledge that every 
 act of the mind is an individual act ; the 
 uni s-ersality, therefore, is not in the act of 
 the mind, but in the object or thing con- 
 ceived. The thing conceived is an attri- 
 bute common to many subjects, or it is a 
 genus or species common to many indivi- 
 duals. 
 
 Suppose I conceive a triangle — that is, a 
 plain figure, terminated by three right 
 lines. He that understands this definition 
 distinctly, has a distinct conception of a 
 triangle. But a triangle is not an indivi- 
 dual ; it is a species. The act of my under- 
 standing in conceiving it is an individual 
 act, and has a real existence ; but the thing 
 conceived is general, and cannot exist with- 
 out other attributes, which are not included 
 m the definition. [445] 
 
 Every triangle that really exists must 
 have a certain length of sides and measure 
 of angles ; it must have place and time. 
 But the definition of a triangle includes 
 neither existence nor any of those attri- 
 butes ; and, therefore, they are not included 
 in the conception of a triangle, which can- 
 not be accurate if it comprehend more than 
 the definition. 
 
 Thus, I think, it appears to be evident, 
 that we have general conceptions that are 
 clear and distinct, both of attributes of 
 things, and of genera and species of things. 
 
 CHAPTER in. 
 
 OF GENERAL CONCEPTIONS FORMED EY 
 ANALYSING OBJECTS. 
 
 We are next to consider the operations 
 of the understanding, by which we are 
 enabled to form general conceptions. 
 
 These appear to me to be three : — First, 
 The resolving or analysing a subject into 
 its known attributes, and giving a name to 
 each attribute, which name shall signify 
 that attribute, and nothing more. 
 
 Secowlli/, The observmg one or more 
 such attributes to be common to many sub- 
 jects. The first is by philosophers called 
 abstraction ; the second may be called 
 generalising ; but both are commonly in- 
 cluded under the name of alistractinn. 
 
 It is diflicult to say which of them goes 
 first, or whether they are not so closely 
 connected that neither can claim the prece- 
 dence. For, on the one hand, to perceive an 
 agreement between two or more objects in 
 the t;ame attribute, seems to require no- 
 thing more than to compare them together. 
 [446] A savage, upon seeing snow and 
 chalk, would find no difliculty in perceiv- 
 ing that they have the same colour. Yet, 
 on the other hand, it seems impossible that 
 he should observe this agreement without 
 
 abstraction — that is, distinguishing in his 
 conception the colour, wherein those two 
 objects agree, from the other qualities 
 wherein they disagree. 
 
 It seems, therefore, that vie cannot 
 generalise without some degree of abstrac- 
 tion ; but I apprehend we may abstract 
 without generalising. For what hinders 
 me from attending to the whiteness of the 
 paper before me, without applying that 
 colour to any other object. The whiteness 
 of this individual object is an abstract con- 
 ception, but not a general one, while applied 
 to one individual only. These two opera- 
 tions, however, are subservient to each 
 other ; for the more attributes we observe 
 and distinguish in any one individual, the 
 more agreements we shall discover between 
 it and other individuals. 
 
 A third operation of the understanding, 
 by which we form abstract conceptions, is 
 the combining into one whole a certain 
 number of those attributes of which we 
 have formed abstract notions, and giving a 
 name to that combination. It is thus we 
 form abstract notions of the genera and 
 species of things. These three operations 
 we shall consider in order. 
 
 With regard to abstraction, strictly so 
 called, I can perceive nothing in it that is 
 difficult either to be understood or practised. 
 What can be more easy than to distinguish 
 the diff'erent attributes which we know to 
 belong to a subject ? In a man, for in- 
 stance, to distinguish hi-* size, his com- 
 plexion, his age, his fortune, his birth, his 
 profession, and twenty other things that 
 belong to him. To think and speak of 
 these things with understanding, is surely 
 within the reach of every man endowed 
 with the human faculties. [447] 
 
 There may be distinctions that require 
 nice discernment, or an acquaintance with 
 the subject that is not common. Thus, a 
 critic in painting may discern the style of 
 Raphael or Titian, when another man 
 could not. A lawyer may be acquainted 
 with many distinctions in crimes, and con- 
 tracts, and actions, which never occurred 
 to a man who has not studied law. One 
 man may excel another in the talent of dis- 
 tinguishing, as he may in memory or in 
 reasoning ; but there is a certain degree of 
 this talent, without which a man would 
 have no title to be considered as a reason- 
 able creature. 
 
 It ought likewise to be observed, that 
 attributes may, with perfect ease, be dis- 
 tinguished and disjoined in our conception, 
 which cannot be actually separated in the 
 subject. Thus, in a body, I can distinguish 
 itssohdity from its extension, and its weight 
 from both. In extension I can distinguish 
 length, breadth, and thickness ; yet none of 
 these can be separated from the body, or 
 
 [445-417]
 
 CHAP. III.] CONCEPTIONS FORMED BY ANALYSING OBJECTS. 39o 
 
 from one another. There may be attri- 
 butes belonging to a subject, and inseparable 
 from it, of which we have no knowledge, 
 and consequently no conception ; but this 
 does not hinder our conceiving distinctly 
 those of its attributes which we know. 
 
 Thus, all the properties of a circle are 
 inseparable from the nature of a circle, 
 and may be demonstrated from its defini- 
 tion ; yet a man may have a perfectly 
 distinct notion of a circle, who knows very 
 few of those properties of it which mathe- 
 maticians have demonstrated ; and a circle 
 probably has many properties which no 
 mathematician ever dreamed of. 
 
 It is therefore certain that attributes, 
 which in their nature are absolutely inse- 
 parable from their subject and from one 
 another, may be disjoined in our conception ; 
 one cannot exist without the other, but one 
 can be conceived without the other. 
 
 Having considered abstraction, strictly 
 so called, let us next consider the operation 
 of generalising, -which is nothing but the 
 observing one or more attributes to be 
 common to many subjects. [4-48] 
 
 If any man can doubt whether there be 
 attributes that are really common to many 
 individuals, let him consider whether there 
 be not many men that are above six feet 
 high, and many below it ; whether there 
 be not many men that are rich, and many 
 more that are poor ; wheth.er there be not 
 many that were born in Britain, and many 
 that were born in France. To multiply 
 instances of this kind, would be to affront the 
 reader's understanding. It is certain, there- 
 fore, that there are innumerable attributes 
 that are really common to many individuals ; 
 and if this be what the schoolmen called 
 universale a parte rei, we may affirm with 
 certainty that there are such universals. 
 
 There are some attributes expressed by 
 general words, of which this may seem more 
 doubtful. Such are the qualities which are 
 inherent in their several subjects. It may 
 be said that every subject hath its own 
 qualities, and that which is the quality of 
 one subject cannot be the quality of atiotlier 
 subject. Thus the whiteness of the sheet 
 of paper upon which I write, cannot be the 
 whiteness of another sheet, though both are 
 called white. The weight of one guinea is 
 not the weight of another guinea, though 
 both are said to have the same weight. 
 
 To this I answer, that the whiteness of 
 this sheet is one thing, whiteness is another ; 
 the conceptions signified by these two forms 
 of speech are as different as the exi>ressions. 
 The first signifies an individual quality 
 really existing, and is not a general con- 
 ception, though it be an abstract one : the 
 second signifies a general conception, wliicli 
 iinpli<-s no existence, but ni:iy be |>rc(licul((l 
 of everything that is white, and in tiie 
 [ii8-4.50] 
 
 same sense. On this account, if one should 
 say that the whiteness of this sheet is the 
 whiteness of another sheet, every man per- 
 ceives this to be absurd ; but when he says 
 both sheets are white, this is true and per- 
 fectly understood. The conception of white- 
 ness implies no existence ; it would remain 
 the same though everything in the universe 
 that is white were annihilated. [449] 
 
 It appears, therefore, that the general 
 names of qualities, as well as of other at- 
 tributes, are applicable to many individuals 
 in the same sense, which cannut be if there 
 be not general conceptions signified by such 
 names. 
 
 If it should be asked, how early, or at 
 what period of life men begin to form general 
 conceptions ? I answer. As soon as a child 
 can say, with understanding, that he has 
 two brothers or two sisters — as soon as he 
 can use the plural number — he must liave 
 general conceptions ; for no iudividual can 
 have a plural number. 
 
 As there are not two individuals in nature 
 that agree in everything, so there are very 
 few that do not agree in some things. We 
 take pleasure from very early years in ob- 
 serving such agreements. One great branch 
 of what we call wit, which, when innocent, 
 gives pleasure to every good-natured man, 
 consists in discovering unexpected agree- 
 ments in things. The author of Iludibras 
 could discern a property common to the 
 morning and a boiled lobster — that both 
 turn from black to red. Swift could see 
 something common to wit and an old cheese. 
 Such unexpected agreements may shew wit ; 
 but there are iimumerable agreements of 
 things which cannot escape the notice of 
 the lowest understanding ; such as agree- 
 ments in colour, magnitude, figure, features, 
 time, place, age, and so fortli. These agree- 
 ments are the foundation of so many com- 
 mon attributes, which are found in the 
 rudest languages. 
 
 The ancient jihilosophers called these 
 universals, or predicables, and endeavouied 
 to reduce them to five classes — to wit, 
 Genus, Species, Specific Difference, Pro- 
 perties, and Accidents. IVrhajis there may 
 1)0 more classes of universals or attributes — 
 for eimmcrations, so very general, are sel- 
 dom complete : but every attribute, common 
 to several individuals, may be expressed by 
 a general term, which is the sign of a 
 general conception. |4r)0| 
 
 How prone men are ti) form general c<ui- 
 ceptions we may see from tlic use of meta- 
 phor, and of I'lie other li;,'ures of speech 
 grounded on similitude Similitude is no- 
 thing else than an agreement of tiie ohjeets 
 compared in one or more attributes , and 
 if there be no attril)nte common to i'otli, 
 theic can be no similituile. 
 
 'i'he siniililiid.s and an;ilogieB beiwr. n
 
 396 
 
 ON THE INTELLECTUAL POWERS. 
 
 [^KSSAY V. 
 
 the Tarious objects that nature presents to 
 us. are infinite and inexhaustible. They 
 not only please, when displayed by the poet 
 or wit in worKs of taste, but they are highly 
 useful in the ordinary communication of our 
 fhoughts and sentiments by language. In 
 the rude lansiunges of barbarous nations, 
 similitudes and analogies supply the want of 
 proper words to express men's sentiments, 
 80 much that in such languages there is 
 hardly a sentence without a metaphor ; and, 
 if we examine tlie most copious and polished 
 languages, weslialbfind that a great pro- 
 portion of the words and phrases which are 
 accounted the most proper, may be said to 
 be the progeny of metaphor. 
 
 As foreigners, who settle in a nation as 
 their home, come at last to he incorporated 
 and lose the denomination of foreigners, so 
 words and phrases, at first borrowed and 
 figurative, by long use become denizens in 
 the language, and lose the denomination of 
 figures of speech. When we speak of the 
 extent of knowledge, the steadiness of virtue, 
 the tenderness of affection, the perspicuity 
 of expression, no man conceives these to be 
 metaphorical expressions ; they are as pro- 
 per as any in the language : yet it appears 
 upon the very face of them, that they 
 must have been metaphorical in those who 
 vsed them first ; and that it is by use and 
 prescription that they have lost the deno- 
 mination of figurative, and acquired a right 
 to be considered as projier words, '^his 
 observation will be found to extend to a 
 g 'eat part, perhaps the greatest part of the 
 words of the most perfect languages. Some- 
 tiines the name of an individual is given to 
 a general conception, and thereby the in- 
 dividual in a manner generalised ; as when 
 the Jew Shylock, in Shakespeare, says — 
 " A Daniel come to judgment ; yea, a 
 D.iniel 1" In this speech, " a Daniel" is 
 an attribute, or an universal- The character 
 of Daniel, as a man of singular wisdom, 
 is abstracted from his person, and considered 
 as capable of being attributed to other per- 
 sons. [451] 
 
 Upon the whole, these two operations of 
 abstracting and generalising appear com- 
 mon to all men that have understanding. 
 The practice of them is, and must be, fami- 
 liar to every man that uses language ; but 
 it is one thing to practise them, and another 
 to explain how they are performed ; as it is 
 ' one thing to see, another to explain how we 
 see. The first is the province of all men, 
 and is the natural and easy operation of the 
 faculties which God hath given us. The 
 second is the province of philosophers, and, 
 though a matter of no great difficulty in it- 
 self, has been much perplexed by the ambi- 
 guity of words, and still more by the 
 hypotheses of philosophers. 
 
 Thus, when I consider a billiard ball, 
 
 its colour is one attribute, which I signify 
 by calling it white ; its figure is another, 
 which is signified by calling it spherical 
 the firm cohesion of its parts is signified by 
 calling it hard ; its recoiling, when it strikes 
 a hard body, is signified by its being called 
 elastic ; its origin, as being part of the tooth 
 of an elephant, is signified by calling it 
 ivory ; and its use by calling it a billiard ball. 
 
 The words by which each of those attri- 
 butes is signified, have one distinct meaning, 
 and in this meaning are applicable to many 
 individuals. They signify not any indivi- 
 dual thing, but attributes common to many 
 individuals ; nor is it beyond the capacity 
 of a child to understand them perfectly, and 
 to apply them properly to every individual 
 in which they are found. 
 
 As it is by analysing a complex object 
 into its several attributes that we acquire 
 our simplest abstract conceptions, it may be 
 proper to compare this analysis with that 
 which a chemist makes of a compounded 
 body into the ingredients which enter into 
 its composition ; for, although there be such 
 an analogy between these two operations, 
 that we give to both the name of analysis 
 or resolution, there is, at the same time, so 
 great a dissimilitude in some respects, that 
 we may be led into error, by applying to one 
 what belongs to the other. [452] 
 
 It is obvious that the chemical analysis 
 is an operation of the hand upon matter, 
 by various material instruments. The an- 
 alysis we are now explaining, is purely an 
 operation of the understanding, which re- 
 quires no material instrument, nor produces 
 any change upon any external thing ; we 
 shall, therefore, call it the intellectual or 
 mental analysis. 
 
 In the chemical analysis, the compound 
 body itself is the subject analysed. A sub- 
 ject so imperfectly known that it may be 
 compounded of various ingredients, when 
 to our senses it appears perfectly simple ;* 
 and even when we are able to analyse it 
 into the different ingredients of which it is 
 composed, we know not how or why the 
 combination of those ingredients produces 
 such a bod}'. 
 
 Thus, pure sea-salt is a body, to appear- 
 ance as simple as any in nature. Every the 
 least particle of it, discernible by our senses, 
 is perfectly similar to every other particle in 
 all its qualities. The nicest taste, the quick- 
 est eye, can discern no mark of its being 
 made up of different ingredients ; yet, by 
 the chemical art, it can he analysed into an 
 acid and an alkali, and can be again pro- 
 duced by the combination of those two in- 
 gredients. But how this combination pro- 
 duces sea-salt, no man has been able to dis- 
 cover. The ingredients are both as unlike 
 
 * .'^omelhiiig seems wanting in this clause. — H. 
 
 [451 ^2]
 
 CHAP. III.] CONCEPTIONS FORMED BY ANALYSING OBJECTS :J97 
 
 the compouiid as any bodies we know. No 
 man could liave guessed, before the tlunii 
 was known, that sea-salt is compounded of 
 tliose two ingredients ; no man could have 
 guessed that the union of those two ingre- 
 dients should produce such a compound as 
 sea-salt. Such, in many cases, are the 
 phsenomena of the chemical analysis of a 
 compound body. [453] 
 
 If we consider the intellectual analysis of 
 an object, it is evident that nothing of this 
 kind can happen ; because the thing ana- 
 lysed is not an external olgect imperfectly 
 known ; it is a conception of the mind it- 
 self. And, to suppose that tliere can be 
 anything in a conception tliat is not con- 
 ceived, is a contradiction. 
 
 The reason of observing this difll'erence 
 between those two kinds of analysis is, that 
 some philosophers, in order to support their 
 systems, liave maintained that a complex, 
 idea may liave the apjiearance of the most 
 perfect simplicity, and retain no similitude 
 of any of the simple ideas of which it is 
 compounded ; just as a white colour may 
 appear perfectly simple, and retain no 
 siniilitude to any of the seven primary 
 colours of which it is compounded ; or as a 
 chemical composition may appear perfectly 
 simple, and retain no similitude to any of 
 the ingredients. 
 
 From which those philosophers havedrawn 
 this important conclusion, that a cluster of 
 the ideas of sense, properly combined, may 
 malce the idea of a mind ; and tliat all the 
 ideas which ]\Ir Locke calls ideas of re- 
 flection, are only compositions of the ideas 
 which we have by our five senses. From 
 this the transition is easy, that, if a proper 
 composition of the ideas of matter may 
 make the idea of a mind, then a proper 
 composition of matter itself may make a 
 mind, and that man is only a piece of 
 matter curiously formed. 
 
 In this curious system, the whole fabric 
 rests ujion this foundation, that a complex 
 idea, which is made up of various sim])le 
 ideas, may appear to be perfectly simple, 
 and to have no marks of composition, be- 
 cause a compound body may ajipear to our 
 tenses to be perfectly simple. 
 
 Upon this fundamental proposition of 
 this system I beg leave to make two re- 
 marks. [454] 
 
 1. Supposing it to be true, it affirms only 
 what mui/ he. We are, indeed, in most 
 cases very imperfect judges of what may 
 be. But this we know, that, were we ever 
 so certain that a thing may be, this is no 
 good reason for believing that it really is. 
 A riiini-he is a mere hyiiotlicsis, which may 
 furnish matter of investigation, but ia not 
 entitled to the least degree of belief. The 
 transition from what may be to what really 
 is, is familiar and easy to those who have a 
 f453-*55] 
 
 predilection for a hypothesis ; but to a man 
 who seeks truth without prejudice or pre- 
 possession, it is a very wide and difficult 
 step, and he will never pajs from the one 
 to the other, without evidence not only that 
 the thing may be, but that it really is. 
 
 2. As far as I am able to judge, this, 
 which it is said may be, cannot be. That 
 a complex idea should be made up of simjile 
 ideas ; so that to a ripe understanding re- 
 flecting upon that idea, there should be no 
 appearance of composition, nothing similar 
 to the sini])le ideas of which it is com- 
 ])Ounded, seems to me to involve a contra- 
 diction. The idea is a conception of the 
 mind. If anytliing more than this is meant 
 by the idea, I know not what it is ; and I 
 wish both to know what it is, and to have 
 proof of its existence. Now, that there 
 should be anything in the conception of an 
 object which is not conceived, appears to 
 me as manifest a contradiction as that 
 there should be an existence which does 
 not exist, or that a thing should be con- 
 ceived and not conceived at the same time. 
 
 But, say these philosophers, a \Nhite 
 colour is ])roduced by the composition of 
 the primary colours, and yet has no resem- 
 blance to any of them. I grant it. But 
 what can be inferred from this with regard 
 to the composition of ideas ? To bring this 
 argument home to the point, they must 
 say, that because a white colour is com- 
 pounded of the primary colours, therefore 
 the idea of a white colour is compounded of 
 the ideas of the primary colours. This 
 reasoning, if it was admitted, would lead 
 to innumerable absurdities. An opaque 
 fluid may be compoumled of two or more 
 pellucid fluids. Hence, we might infer, 
 with equal force, that the idea of an 0])a(iue 
 fluid may be coniiiounded of the idea of two 
 or more pellucid fluids. [455] 
 
 Nature's way of con)pounding bodies, 
 and our way of comjiounding ideas, are so 
 diH'erent in many respects, that we ciinnot 
 reason from the one to the other, unless it 
 can be found that ideas are combined by 
 fermentations and electi\e attractions, and 
 may be analysed in a furnace by the foice 
 of fire and of iiunstruums. Until this dis- 
 covery be made, we must liohl those to be 
 simple ideas, which, ujion the most atten- 
 tive reflection, have no njipiarance of com- 
 ])Osition ; and those only to be the ingre- 
 dients of complex ideas, which, by attentive 
 reflection, can be perceived to be contained 
 in them. 
 
 If the idea of mind and its operations, 
 may be coiii|i()imd<-(l of the ideas of matter 
 and its qualities, wliy may not the idea of 
 matter be compounded of tin- idtiin "f 
 mind ? There is thp same evidence for the 
 last m<iy-l,e us for the first. And why may 
 not the idea of sound be compounded of th«
 
 398 
 
 ON THE INTELLECTUAL POWERS. 
 
 [essay 
 
 ideas of colour ; or the idea of colour of 
 those of sound ? Why may not the idea of 
 wisdom be compounded of ideas of folly ; 
 or the idea of truth of ideas of absurdity ? 
 But we leave these mysterious may-bes to 
 them that have faith to receive them. 
 
 CHAPTER IV. 
 
 OF GENERAL CONCEPTIONS FORMED BY COM- 
 BINATION. 
 
 As, by an intellectual analysis of objects, 
 we form general conceptions of single attri- 
 butes, (which, of all conceptions that enter 
 into the human mind, are the most simple,) 
 so, by combining several of these into one 
 parcel, and giving a name to that combina- 
 tion, we form general conceptions that may 
 be very complex, and, at the same time, 
 very distinct. [456] 
 
 Thus, one who, by analysing extended 
 objects, has got the simple notions of a 
 point, a line, straight or curve, an angle, a 
 surface, a solid, can easily conceive a plain 
 surface, terminated by four equal straight 
 lines, meeting in four points at right angles. 
 To this species of figure he gives the name 
 of a square. In like manner, he can con- 
 ceive a solid terminated by six equal squares, 
 and give it the name of a cube. A square, 
 a cube, and every name of mathematical 
 figure, is a general term, expressing a com- 
 plex general conception, made by a certain 
 combination of the s^imple elements into 
 which we analyse extended bodies. 
 
 Every mathematical figure is accurately 
 defined, by enumerating the simple ele- 
 ments of which it is formed, and the man- 
 ner of their combination. The definition 
 contaiiis the whole essence of it. And 
 every property that belongs to it may be 
 deduced by demonstrative reasoning from 
 its definition. It is not a thing that 
 exists, for then it would be an individual ; 
 but it is a thing that is conceived without 
 regard to existence. 
 
 A farm, a manor, a parish, a county, a 
 kingdom, are complex general conceptions, 
 formed by various combinations and modi- 
 fications of inhabited territory, under cer- 
 tain forms of government. 
 
 Different combinations of military men 
 form the notions of a company, a regiment, 
 an army. 
 
 Tiie several crimes which are the objects 
 of criminal law, such as theft, murder, 
 robbery, piracy, what are they but certain 
 combinations of human actions and inten- 
 tions, which are accurately defined in 
 criminal law, and which it is found con- 
 venient to comprehend under one name, 
 and consider as one thing ? 
 
 When we nbserve that nature, in her 
 
 animal, vegetable, and inanimate produc- 
 tions, has formed many individuals that 
 agree in many of their qualities and attri- 
 butes, we are led by natural instinct to 
 expect their agreement in other qualities, 
 which we have not had occasion to perceive. 
 [457] Thus, a child who has once burnt 
 his finger, by putting it in the flame of one 
 candle, expects the same event if he puts it 
 in the flame of another candle, or in any 
 flame, and is thereby led to think that the 
 quality of burning belongs to all flame. 
 This instinctive induction is not justified 
 by the rules of logic, and it sometimes leads 
 men into harmless mistakes, which expe- 
 rience may afterwards correct ; but it pre- 
 serves us from destruction in innumerable 
 dangers to which we are exposed. 
 
 The reason of taking notice of this prin- 
 ciple in human nature in this place is, that 
 the distribution of the productions of na- 
 ture into genera and species becomes, on 
 account of this principle, more generally 
 useful. 
 
 The physician expects that the rhubarb 
 which has never yet been tried will have 
 like medical virtues with that which he has 
 prescribed on former occasions. Two par- 
 cels of rhubarb agree in certain sensible 
 qualities, from which agreement they are 
 both called by the same general name 
 rhubarb. Therefore it is expected that 
 they will agree in their medical virtues. 
 And, as experience has discovered certain 
 virtues in one parcel, or in many parcels, 
 we presume, without experience, that the 
 same virtues belong to all parcels of rhubarb 
 that shall be used. 
 
 If a traveller meets a horse, an ox, or a 
 sheep, which he never saw before, he is 
 under no apprehension, believing tliese ani- 
 mals to be of a species that is tame and in- 
 off'ensive. But he dreads a lion or a tiger, 
 because they are of a fierce and ravenous 
 species. 
 
 We are capable of receiving innumerable 
 advantages, and are exposed to innumer- 
 able dangers, from the various productions 
 of nature, animal, vegetal ile, and inanimate. 
 The life of man, if an hundred times longer 
 than it is, would be insufficient to learn 
 from experience the useful and hurtful qua- 
 lities of every individual production of na» 
 ture taken singly. [458] 
 
 The Author of Nature hath made pro- 
 vision for our attaining that knowledge of 
 his works which is necessary for our subsist- 
 ence and preservation, partly by the consti- 
 tution of the productions of nature, and partly 
 by the constitution of the human mind. 
 
 For, first. In the productions of nature, 
 great numbers of individuals are made so 
 like to one another, both in their obvious 
 and in their more occult qualities, that we 
 are not only enabled, but invited, as it were, 
 
 [456-4-58/
 
 CHAP. IV.] CONCEPTIONS FORMED BY COMBINATION. 
 
 399 
 
 to reduce them into classes, and to give a 
 general name to a class ; a name which is 
 common to every individual of the class, 
 because it comprehends in its signification 
 those qualities or attributes only that are 
 common to all the individuals of tliat class. 
 
 Seron'l/i/, The human mind is so framed, 
 that, from the agreement of individuals in 
 the more obvious qualities by which we 
 reduce them into one class, we are naturally 
 led to expect that they will be found to 
 agree in their more latent qualities — and in 
 this we are seldom disappointed. 
 
 We have, therefore, a strong and rational 
 inducement, both to distribute natural sub- 
 stances into classes, genera and species, 
 under general names, and to do this with all 
 the accuracy and distinctness we are able. 
 For the more accurate our divisions are 
 made, and the more distinctly the several 
 species are defined, the more securely we 
 may rely that the qualities we find in one or 
 in a few individuals will be found in all of 
 the same species. 
 
 Every species of natural s;ibstances which 
 has a name in language, is an attribute of 
 many individuals, and is itself a combination 
 of more simple attributes, which we observe 
 to be common to those individuals. [459] 
 
 We shall find a great part of the words 
 of every language — nay, I apprehend, the 
 far greater part — to signify combinations of 
 more simple general conceptions, which 
 men have found proper to be bound up, as 
 it were, in one parcel, by being designed by 
 one name. 
 
 Some general conceptions there are, which 
 may more properly be called compositions 
 or works than mere combinations. Thus, 
 one may conceive a machine which never 
 existed. He may conceive an air in music, 
 a poem, a plan of architecture, a plan of 
 government, a plan of conduct in public or 
 in private life, a sentence, a discourse, a 
 treatise. Such compositions are things 
 conceived iu the mind of the author, not 
 individuals that really exist ; and the .same 
 general conception which the author had, 
 may be communicated to others by language. 
 
 Thus, the " Oceana" of Harrington was 
 Conceived in the mind of its author. The 
 materials of which it Ls composed are things 
 conceived, not tilings that existed. His 
 senate, his popular assembly, his magis- 
 trates, his elections, are all conceptions of 
 his mind, and the whole is one com[)lex 
 conception. And the same nuiy be said of 
 every work of the human understanding. 
 
 Very difi'erent from these are the works 
 of God, which we behold. Th<!y are w<n'Us 
 of creative power, not of understanding 
 only. Tiiey have a real existence. Our 
 best coiicet)tion3 of them are j)artial and 
 imperfect. But of the works of the -human 
 understanding our conception may be pc;r- 
 L4-.59-Kil] 
 
 feet and complete. They are nothing but 
 what the author conceived, and what he can 
 ex[)ress by language, so as to convey his 
 conception perfectly to men like himself. 
 
 Although such works are indeed complex 
 general conceptions, they do not so properly 
 belong to our present subject. They are 
 more the objects of judgment and of taste, 
 than of bare conception or simple appre- 
 hension. [460] 
 
 To return, therefore, to those complex 
 conceptions which are formed merely by 
 combining those that are more simple. 
 Nature has given us the power of combin- 
 ing such simple attributes, and such a num- 
 ber of them as we find proper ; and of 
 giving one name to that combination, and 
 considering it as one object of thought. 
 
 The simple attributes of things, which 
 fall under our observation, are not so nume- 
 rous but that they may all have names in a 
 copious language. But to give names to 
 all the combinations that can be made of 
 two, three, or more of them, would be im- 
 possible. The most copious languages have 
 names but for a very small part. 
 
 It may likewise be observed, that the 
 combinations that have names are nearly, 
 though not perfectly, the same in the dif- 
 ferent languages of civilized nations that 
 have intercourse with one another. Hence 
 it is, that the Lexicographer, for the most 
 part, can give words in one language answer- 
 ing perfectly, or very nearly, to those of 
 another ; and what is written in a simple 
 style in one language, can be translated al- 
 most word for word into auother * 
 
 From these observations we may con- 
 clude that there are either certain common 
 principles of human nature, or certain com- 
 mon occurrences of human life, which dis- 
 pose men, out of an infimte number that 
 might be formed, to form certain combina- 
 tions rather than others. 
 
 Mr Hume, in order to account for this 
 phienomenon, has recourse to what he calls 
 the associating qualities of ideas ; to wit, 
 causaliiin, contiguity in time and place, mid 
 simililude. He conceives^" That one of 
 the most remarkable etfects of those associa- 
 ting qualities, is the complex ideas which 
 are the common subjects of our thougliis. 
 That this also is the cause why languages 
 so nearly correspond to oneanotlier; Nature 
 in a manner pointing out to every one those 
 ideas which are most proper to be united 
 into a complex one." [4U1] 
 
 I agree with this ingenious author, that 
 Nature in a manner points out those simple 
 idea-s which are most propir to be united 
 into a coni|)lex one ; but .Nature iloea this, 
 not solely or chietly by the relations between 
 the simple iduxs of contigui y, causation, 
 
 * Thin is oii'y strlcily trui' of tlic woriU rcl.ilive to 
 
 Dl'jCCtll of bt'tlKC— 11.
 
 400 
 
 ON THE INTELLECTUAL POWDERS. 
 
 [essay 
 
 causation, and resemblance j but ratlier by 
 the fitness oF the combinations we make, to 
 aid our own conceptions, and to convey 
 tliem to others by language easily and 
 agreeably. 
 
 The end and use of language/ without 
 regard to tlie associating qualities of ideas, 
 will lead men that have common under- 
 standing to lorm such complex notions as 
 are proper for expressing their wants, their 
 thoughts, and their desires : and in every 
 l-injiuage we shall find these to be the com- 
 plex notions that have names. 
 
 In the rudest state of society, men must 
 have occasion to form the general notions of 
 man, woman, father, mother, son, daughter, 
 sister, brother, neighbour, friend, enemy, 
 and many others, to express the common 
 relations of one person to another. 
 
 If they are employed in hunting, they 
 must have general terms to express the 
 various implements and operations of the 
 chase. Their houses and clothing, however 
 simple, will furnish another set of general 
 terms, to express the materials, the work- 
 manship, and the excellencies and defects 
 of those fabrics. If they sail upon rivers 
 or upon the sea, this will give occasion to a 
 great number of general terms, which other- 
 wise would never have occurred to their 
 thoughts. 
 
 The same thing may be said of agricul- 
 ture, of pasturage, of every art they prac- 
 tise, and of every branch of knowledge they 
 attain. The necessity of general terms for 
 communicating our sentiments is obvious ; 
 and the invention of them, as far as we find 
 them necessary, requires no other talent 
 but that degree of understanding which is 
 common to men. [462] 
 
 The notions of debtor and creditor, of 
 profit and loss, of account, balance, stock 
 on hand, and many others, are owing to 
 commerce. The notions of latitude, longi- 
 tude, course, distance, run, and those of 
 ships, and of their various parts, furniture, 
 and operations, are owing to navigation. 
 The anatomist must have names for the 
 various similar and dissimilar parts of the 
 human body, and words to express their 
 figure, position, structure, and use. The 
 physician must have names for the various 
 diseases of the body, their causes, symp- 
 toms, and means of cure. 
 
 The like may be said of the grammarian, 
 the logician, the critic, the rhetorician, the 
 moralist, the naturalist, the mechanic, and 
 every man that professes any art or science. 
 
 When any discovery is made in art or in 
 nature, which requires new combinations and 
 new words to express it properly, the in- 
 vention of these is easy to those who have 
 a distinct notion of the thingtobe expressed ; 
 and such words will readily be adopted, and 
 receive the public sanction. 
 
 If, on the other hand, any man of emi- 
 nence, through vanity or want of juilgnicnt, 
 should invent new words, to express com- 
 binations tliat have neither beauty nor 
 utiHty, or which may as well be expressed 
 in the current laaiguage, his authority may 
 give them currency for a time with servile 
 imitators or blind admirers ; but the judi- 
 cious will laugh at them, and they will soon 
 lose their credit. So true was the observa- 
 tion made by Fomponius Marcellus, an 
 ancient grammarian, to Tiberius Caesar : — 
 '' You, Ctesar, have power to make a man 
 a denizen of Rome, but not to make a word 
 a denizen of the Roman language."* 
 
 Among nations that are civilized, and 
 have intercourse with one another, the most 
 necessary and useful arts will be common ; 
 the important parts of human knowledge 
 will be common ; their several languages 
 will be fitted to it, and consequently to one 
 another. [4t)3] 
 
 New inventions of general use give an 
 easy birth to new complex notions and new 
 names, which spread as far as the inven- 
 tion does. How many new complex notions 
 have been formed, and names for them 
 invented in the languages of Europe, by the 
 modern inventions of printing, of gun- 
 powder, of the mariner's compass, of opti- 
 cal glasses ? The simple ideas combined 
 in those complex notions, and the associat- 
 ing qualities of those ideas, are very an- 
 cient ; but they never produced those com- 
 plex notions until there was use for them. 
 
 What is peculiar to a nation in its cus- 
 toms, manners, or laws, will give occasion 
 to complex notions and words peculiar to 
 the language of that nation. Hence it is 
 easy to see why an impeachment, and an 
 attainder, in the English language, and 
 ostracism in the Greek language, have not 
 names answering to them in other lan- 
 guages. 
 
 I apprehend, therefore, that it is utility, 
 and not the associating qualities of the ideas, 
 that has led men to form only certain com- 
 binations, and to give names to them in 
 language, while they neglect an in. nite 
 number that might be formed. 
 
 The common occurrences of life, in the 
 intercourse of men, and in their occupa- 
 tions, give occasion to many complex no- 
 tions. We see an individual occurrence, 
 which draws our attention more or less, 
 and may be a subject of conversation. 
 Other occurrences, similar to this in many 
 respects, have been observed, or may be 
 expected. It is convenient that we should 
 be able to speak of what is common to 
 them all, leaving out the unhnportant cir- 
 
 * " Tu, Ca?-ai', clvitatein .dare pntcs hominitius, 
 verbis lion poies." See Suetonius De Illust.-Gram- 
 mat.,c. 2-2. — H. 
 
 [462,
 
 CHAP. IV.] CONCKPTIONS 1-ORMED BY COMBINATION. 
 
 401 
 
 cumstances of time, place, and persons. 
 This we can do with great ease, by giving 
 a name to what is eomniou to all those 
 individual occurrences. Such a name is a 
 great aid to language, because it compre- 
 hends, in one word, a great number of 
 simple notions, which it would be very 
 tedious to express in detail. [40'4] 
 
 Thus, men have formed the complex 
 notions of eating. drinKing, sleeping, walk- 
 ing, riding, running, buying, selling, plough- 
 ing, sowing, a dance, a feast, war, a battle, 
 victory, triumph ; and others, without 
 number. 
 
 Such things must frequently be the sub- 
 ject of conversation ; and, if we had not a 
 more compendious way of expressing them 
 than by a detail of all the simple notions 
 they comprehend, we should lose the benefit 
 of speech. 
 
 The different talents, dispositions, and 
 habits of men in society, being interesting 
 to those who have to do with them, will in 
 every language have general names — such 
 as wise, foolish, knowing, ignorant, plain, 
 cunning. In every operative art, the tools, 
 instruments, materials, the work produced, 
 aiid the various excellencies and defects of 
 these, must have general names. 
 
 The various relations of persons, and of 
 things which cannot escape tlie observation 
 of men in society, lead us to many complex 
 general notions ; such as father, brother, 
 friend, enemy, master, servant, property, 
 theft, rebellion. 
 
 The terms of art in the sciences make 
 another class of general names of co^nplex 
 notions ; as in mathematics, axiom, defini- 
 tion, problem, theorem, demonstration. 
 
 1 do not attempt a complete enumeration 
 even of the classes of complex general con- 
 ceptions. Those I have named as a speci- 
 men, I think, are mostly comprehended 
 under what Mr Locke calls mixed modes 
 and relations; which, he justly observes, 
 have names given them in language, in 
 preference to innumerable others that might 
 be formed ; for this reason only, that they 
 are useful for the purpose of coiinnuuicat- 
 ing our thoughts by language- [4(i5] 
 
 in all the languages of mankind, not only 
 the writings and discourses of the learned, 
 but the conversation of the vulgar, is almost 
 entirely made up of general v.ords, which 
 are the signs of general concei)tioi)s, either 
 simj.le or complex. And in every language, 
 wf find the terms signifying complex no- 
 tions to be such, and only such, as the use 
 of language requires. 
 
 There remains a very large class of com- 
 plex general terms, on which I shall make 
 some observations; I mean those l)y which 
 we name the species, genera, and tribes of 
 natural substances. 
 
 It is utility, indeed, that leads us to give 
 [lG4-4f)fi]* 
 
 general names to the various species of na- 
 tural substances ; but, in combining the 
 attributes which are included under the 
 specific name, we are more aided and di- 
 rected by nature than in forming other com- 
 binations of mixed modes and relations. In 
 the last, the ingredients are brought to- 
 gether in the occurrences of life, or in the 
 actions or thoughts of men. But, in the 
 first, the ingredients are united by nature in 
 many individual substances which God has 
 made. We form a general notion of those 
 attributes wherein many ind viduals agree. 
 We give a specific name to this combina- 
 tion, which name is common to all sub- 
 stances having those attributes, which 
 either do or may exist. The specific name 
 comprehends neither more nor fewer attri- 
 butes than we find proper to put into its 
 definition. It comprehends not time, nor 
 place, nor even existence, although there 
 can be no individual without these. 
 
 This work of the understanding is abso- 
 lutely necessary for speaking intelligibly of 
 the 1 productions of nature, and for reaping 
 the benefits we receive, and avoiding the 
 dangers we are exposed to from them. The 
 individuals are so many, that to give a 
 proper name to each would be beyond the 
 j)ower of language. If a good or bad qua- 
 lity was observed in an individual, of how 
 small use would this be, if there was not a 
 species in which the same quality might be 
 exjiected ! [46(J] 
 
 AV'ithout some general knowledge of the 
 qualities of natural substances, human life 
 could not be preserved. And there can be 
 no general knowledge of this kind without 
 reducing- them to species under specific 
 names. Tor this reason, among the rudest 
 nations, we find names for fire, water, earth, 
 air, mountains, fountains, rivers ; for the 
 kinds of vegetables they use ; of animals 
 they hunt or tame, or that are found useful 
 or hurtful. 
 
 Each of those names signifies in general 
 a substance having a certain combination of 
 attributes. The name, therefore, must be 
 common to all substances in which those 
 attributes are found. 
 
 Such general names of substances being 
 found in all vulgar languages, before philo- 
 sophers began to make accurate divisions 
 and less obvious distinctions, it is not to be 
 expected that their moaning shoMd be more 
 jirecise than is necessary for the common 
 purposes of life. 
 
 As the knowledge of nature advances, 
 more species of natural substanccB nro 
 observed, and tlx'ir nn-UA qnalitius <lic-- 
 covered. In order that this imixntant |..i:t 
 of human knowledge may be ei.niiimnicat. d, 
 and handed down to future geiierutinns, it 
 is not sufficient that the species Itiive names. 
 Such is the flucuiatiig btato of bngung", 
 
 'J I)
 
 402 
 
 ON THE INTELLECTUAL POWERS. 
 
 I ESSAY V 
 
 that a genenvl name will not always retain 
 the same precise signification, unless it have 
 a definition in whicli men are disposed to 
 acquiesce- 
 There was undoubtedly a great fund of 
 natural knowledge among the Greeks and 
 Romans in the time of Pliny. There is a 
 great fund in his Natural History ; but 
 much of it is lost to us — for this reason 
 among others, that we know not what 
 species of substance he means by such a 
 name. 
 
 Nothing could have prevented this loss 
 but an accurate definition of the name, by 
 which the species might have been distin- 
 guished from all others as long as that name 
 and its definition remained. [467] 
 
 To prevent such loss in future times, 
 modern philosophers have very laudably 
 attempted to give names and accurate defin- 
 itions of all the known species of sub- 
 stances wherewith the bountiful Creator 
 hath enriched our globe. 
 
 This is necessary, in order to form a 
 copious and distinct language concerning 
 them, and, consequently, to facilitate our 
 knowledge of them, and to convey it to 
 future generations. 
 
 Every species that is known to exist 
 ought to have a name ; and that name 
 ought to be defined by such attributes as 
 serve best to distinguish the species from 
 all others. 
 
 Nature invites to this work, by having 
 formed things so as to make it both easy 
 and important. 
 
 For, first, We perceive numbers of indi- 
 vidual sulif-tances so like in their obvious 
 qualities, that the most unimproved tribes 
 of men consider them as of one species, and 
 give them one common name. 
 
 Secondly, The more latent qualities of 
 substances are generally the same in all 
 the individuals of a species ; so that what, 
 by observation or experiment, is found in 
 a few individuals of a species, is presumed 
 and commonly found to belong to the 
 whole. By this we are enabled, from par- 
 ticular facts, to draw general conclusions. 
 This kind of induction is, indeed, the mas- 
 ter-key to the knowledge of Nature, without 
 which we could form no general conclu- 
 sions in that branch of philosopliy. 
 
 And, ihirc/li/. By the very constitution 
 of our nature, we are led, without reason- 
 ing, to ascribe to the whole species what 
 we have found to belong to the individuals. 
 It is thus we come to know that fire burns 
 and water drowns ; that bodies gravitate 
 and bread nourishes. [4G8] 
 
 The species of two of the kingdoms of 
 Nature— to wit, the animal and the vege- 
 table — seem to be fixed by Nature, by the 
 power they have of producing their like. 
 And, in these, men, in all ages and nations. 
 
 have accounted the parent and the progeny 
 of the same species. The diff"erences among 
 Naturalists, with regard to the species of 
 these two kingdoms, are very inconsider- 
 able, and may be occasioned by the changes 
 produced by soil, climate, and culture, and 
 sometimes by monstrous productions, which 
 are comparatively rare. 
 
 In the inanimate kingdom we have not 
 the same means of dividing things into 
 species, and, therefore, the limits of species 
 seem to be more arbitrary. But, from the 
 progress already made, there is ground to 
 hope that, even in this kingdom, as the 
 knowledge of it advances, the various 
 species may be so well distinguished and 
 defined as to answer every valuable pur- 
 pose. 
 
 When the species are so numerous as to 
 burden the memory, it is greatly assisted 
 by distributing them into genera, the <jeiiera 
 into tribes, the tribes into orders, and the 
 orders into classes. 
 
 Such a regular distribution of natural 
 substances, by divisions and subdivisions, 
 has got the name of a system. 
 
 It is not a system of truths, but a system 
 of general terms, with their definitions ; 
 and it is not only a great help to memory, 
 but facilitates very much the definition of 
 the terms. For the definition of the genus 
 is common to all the species of that genus, 
 and so is understood in the definition of 
 each species, without the trouble of repeti- 
 tion. In like manner, the definition of a 
 tribe is understood in the definition of every 
 genus, and every species of that tribe ; and 
 the same may be said of every superior 
 division. [46!)] 
 
 The effect of such a systematical distri- 
 bution of the productions of Nature is seen 
 in our systems of zoology, botany, and min- 
 eralogy ; in which a species is commonly 
 defined accurately in a line or two, which, 
 without the systematical arrangement, could 
 hardly be defined in a page. 
 
 With regard to the utility of systems of 
 this kind, men have gone into contrary ex- 
 tremes ; some have treated them with con- 
 tempt, as a mere dictionary of words ; 
 others, perhaps, rest in such systems as all 
 that is worth knowing in the works of 
 Nature. 
 
 On the one hand, it is not the intention 
 of such systems to communicate all that is 
 known of the natural productions which 
 they describe. The properties most fit for 
 defining and distinguishing the several 
 species, are not always those that are most 
 useful to be known. To discover and to 
 communicate the uses of natural substances 
 in life and in the arts, is, no doubt, that 
 part of the business of a naturalist which is 
 the most unportant ; and the systematical 
 arrangement of them is chiefly to be valued 
 
 [467-469"]
 
 CHAP, v.] OF NAMES GIVEN TO GENERAL NOTIONS. 
 
 403 
 
 for its subserviency to this end. This every 
 judicious naturaUst will grant. 
 
 But, on the other hand, the labour is not 
 to be despised, by which the road to an use- 
 ful and important branch of knowledge is 
 made easy in all time to come; especially 
 when this labour reijuires both extensive 
 knowledge and great abilities. 
 
 The talent of arranging properly and 
 definmg accurately, is so rare, and at the 
 same time so useful, that it may very justly 
 be considered as a proof of real genius, and 
 as entitled to a high degree of praise. There 
 is an intrinsic beauty in arrangement, which 
 captivates the mind, and gives pleasure, 
 even abstracting from its utility ; as in most 
 other things, so in this particularly, Nature 
 has joined beauty with utility. The arrange- 
 ment of an army in the day of battle is a 
 grand spectacle. The same men crowded 
 in a fair, have no such effect. It is not 
 more strange, therefore, that some men 
 spend their days in studying systems of 
 Nature, than that other men employ their 
 lives in the study of languages. The most 
 important end of those systems, surely, is 
 to form a copious and an unambiguous lan- 
 guage concerning the productions of Nature, 
 by which every useful discovery concerning 
 them may be communicated to the present, 
 and transmitted to all future generations, 
 without danger of mistake. [470] 
 
 General terms, especially such as are 
 complex in their signification, will never 
 keep one precise meaning, without accurate 
 definition ; and accurate definitions of such 
 terms can in no way be formed so easily and 
 advantageously as by reducing the things 
 they signify into a regular system. 
 
 Very eminent men in the medical profes- 
 sion, in order to remove all ambiguity in 
 the names of diseases, and to advance the 
 heiUiug art, have, of late, attempted to re- 
 duce into a systematical order the diseases 
 of the human body, and to give distinct 
 names and accurate definitions of the seve- 
 ral species, iienera, orders, and classes, into 
 which they distribute them ; and I appre- 
 hend that, in every art and science, where 
 the terms of the art have any ambiguity 
 that obstructs its progress, this method will 
 be found the easiest and most successful for 
 the remedy of that evil. 
 
 It were even to be wished tliat the gene- 
 ral terms which we find in common lan- 
 guage, as well as those of the arts and 
 sciences, could be reduced to a systematical 
 arrangement, and defined so as that they 
 might be free from ambiguity ; but, per- 
 haps, the obstacles to this are insurmount- 
 able. I know no man who has attemi)tedit 
 but Bishop Wilkins in his Essay towards a 
 real character and a philosophical language. • 
 
 * in this altcmpt Wilkiim was prccivled liy our 
 [4-70-472] 
 
 The attempt was grand, and worthy of a 
 man of genius. 
 
 The formation of such systems, therefore, 
 of the various productions of Nature, in- 
 stead of being despised, ought to be ranked 
 among the valuable improvements of modern 
 ages, and to be the more esteemed that its 
 utility reaches to the most distant future 
 times, and, like the invention of writing, 
 serves to embalm a most important branch 
 of human knowledge, and to preserve it from 
 being corrupted or lost, [47 1 ] 
 
 CHAPTER V. 
 
 OBSERVATIONS CONXEKNINGTHE NAMES GIVKX 
 TO OUR GENERAL NOTIONS. 
 
 Having now explained, as well as I ara 
 able, those operations of the mind by which 
 we analyse the objects which nature pre- 
 sents to our observation, into their simple 
 attributes, giving a general name to each, and 
 by which we combine any number of such 
 attributes into one whole, and give a general 
 name to that combination, I shall ofi'er some 
 observations relating to our general notions, 
 whether simple or complex. 
 
 I apprehend that the names given to 
 them by modern philosophers, have contri- 
 buted to darken our speculations about them, 
 and to render them difficult and abstruse. 
 
 We call them general notions, concep- 
 tions, ideas. The words notion and con- 
 ception, in their proper and most common 
 sense, signify the act or operation of the 
 mind in conceiving an object. In a figura- 
 tive sense, they are sometimes put for the 
 object conceived. And I think they are 
 rarely, if ever, used in this figurative sense, 
 except when we speak of what we call 
 general notions or general conceptions. The 
 word idea, as it is used in modern times, 
 has the same ambiguity. 
 
 Now, it is only in the last of these senses, 
 and not in the first, that we can be said to 
 have general notions or conceptions. The 
 generality is in the object conceived, and 
 not in the act of the mind by which it is 
 conceived. Every act of the mind is an in- 
 dividual act, which does or did exist. [472] 
 But we have power to conceive things which 
 neither do nor ever did exist. We have 
 power to conceive attributes without regard 
 to their existence. The conception of such 
 an attribute is a real and individual act of 
 the mind ; but the attribute conceived is 
 coninion to many indiviiluals that do or may 
 exist. We arc tcKj ai>t to confound an ob- 
 ject of conception with the cunccption of 
 
 rounfryman DalKirno : and from UalsArnn It (• 
 liiKhly probable I lint Wilkins borrowed the lilo.i. 
 Hut fvi'ii IJal(!»riio w<iii not (lie Orkt wlio lomclvwl 
 Jill' pr<ijcct. — II. 
 
 2 i> 2
 
 404 
 
 ON THE INTELLECTUAL POWERS. 
 
 Lessay v. 
 
 that object. But tlie danger of doing tliis 
 must be much greater when the object of 
 conception is called a conception. 
 
 The Peripatetics gave to such objects of 
 conception the names of universals, and of 
 predicables. Those names had no ambi- 
 guity, and I think were much more fit to 
 express what was meant by them than the 
 names we use. 
 
 It is for tliis reason that I liave so often 
 used the word attribute, which has the same 
 meaning with predicable. And, for the same 
 reason, I have thought it necessary repeat- 
 edly to warn the reader, tliat wlien, in com- 
 pUance with custom, I speak of general 
 notions or general conceptions, I always 
 mean things conceived, and not the act of 
 the mind in conceiving them. 
 
 The Pytliagoreans and Platonists gave 
 the name of ideas to such general objects of 
 conception, and to nothiiig else. As we 
 borrowed the word idea from them, so that 
 it is now familiar in all the languages of 
 Europe, I think it would have been happy 
 if we had also borrowed their meaning, and 
 liad used it only to signify what they meant 
 by it. I apprehend we want an unambigu- 
 ous word to distinguish things barely con- 
 ceived from things that exist. If the word 
 idea was used for this purpose only, it would 
 be restored to its original meaning, and 
 supply that want. 
 
 We may surely agree with the Platonists 
 in the meaning of the word idea, without 
 adopting their theory concerning ideas. We 
 need not believe, with them, that ideas are 
 eternal and self-existent, and that they 
 have a more real existence than the things 
 we see and feel. [473] 
 
 They were led to give existence to ideas, 
 from the common prejudice that everything 
 which is an object of conception must 
 really exist ; and, having once given exist- 
 ence to ideas, the rest of their mysterious 
 system about ideas followed of course ; for 
 things merely conceived have neither be- 
 ginning nor end, time nor place ; they are 
 subject to no change ; they are the patterns 
 and exemplars according to which the 
 Deity made everything that he made ; for 
 the work must be conceived by the artificer 
 before it is made. 
 
 These are undeniable attributes of the 
 ideas of Plato ; and, if we add to them that 
 of real existence, we have the whole myste- 
 rious system of Platonic ideas. Take away 
 the attribute of existence, and suppose 
 them not to be things that exist, but 
 things tliat are barely conceived, and all 
 the mystery is removed ; all that remains 
 is level to the human understanding. 
 
 The word essence came to be much used 
 among the schoolmen, and what the Pla- 
 tonists called the idea of a species, they 
 called its essence. The word essentia is 
 
 said to have been made by Cicero ; but 
 even his authority could not give it cur- 
 rency, until long after his time. It came 
 at last to be used, and the schoolmen fell 
 into much the same opinions concerning 
 essences, as the Platonists held concerning; 
 ideas. The essences of things were held to 
 be UTicreated, eternal, and iinmutable. 
 
 ]Mr Locke distinguishes two kinds of 
 essence, the real and the nominal. By the 
 real essence, he means the constitution of 
 an individual, which makes it to be what it 
 is. This essence must begin and end with 
 the individual to which it belongs. It is 
 not, therefore, a Platonic idea. But what 
 Mr Locke calls the nominal essence, is the 
 constitution of a species, or that which 
 makes an individual to be of such a species ; 
 and this is nothing but that combination of 
 attributes which is signified by the name of 
 the species, and which we conceive without 
 regard to existence. [474] 
 
 The essence of a species, therefore, is 
 what the Platonists called the idea of the 
 species. 
 
 If the word idea be restricted to the 
 meaning which it bore among the Plato- 
 nists and Pythagoreans, many things which 
 I\Ir Locke has said with regard to ideas 
 will be just and true, and others will not. 
 
 It will be true that most words (in- 
 deed all general words) are the signs of 
 ideas ; but proper names are not : they 
 signify individual things, and not ideas. It 
 will be true not only that there are general 
 and absti'act ideas, but that all ideas are 
 general and abstract. It will be so far 
 from the truth, that all our simple ideas 
 are got immediately, either from sensation 
 or from consciousness, that no simple 
 idea is got by either, without the co-opera- 
 tion of other powers. The objects of sense, 
 of memory, and of consciousness, are not 
 ideas but individuals ; they must be anal- 
 ysed by the understanding into their simple 
 ingredients, before we can have simple 
 ideas ; and those simple ideas must be 
 again combined by the understanding, in 
 distinct parcels, with names annexed, in 
 order to give us complex ideas. It will be 
 probable not only that brutes have no ab- 
 stract ideas, but that they have no ideas at all. 
 I shall only add that the learned author 
 of the origin and progress of language, and, 
 perlmps, his learned friend, Mr Harris, are 
 the "lily modern authors 1 have met with 
 wlio restrict the word idea to this meaning. 
 Their acquaintance with ancient philosophy 
 led fhem to this. What pity is it that a 
 word which, in ancient philosophy, had a 
 distinct meaning, and which, if kept to 
 that meaning, would have been a real ac- 
 quisition to our language, should be used 
 by the moderns in so vague and ambiguous 
 a manner, that it is more apt to perplex 
 
 [473, 474]
 
 <;map. V 
 
 I.] 
 
 OPINIONS ABOUT UNIVERSALS. 
 
 405 
 
 and darken our speculations, than to convey 
 useful knowledge ! 
 
 From all that has been said about ab- 
 stract and general conceptions, I think we 
 may draw the following conclusions con- 
 cerning them. [475] 
 
 First, That it is by abstraction that the 
 mind is furnished with all its most simple 
 and most distinct notions. The simplest 
 objects of sense appear both complex and 
 indistinct, until by abstraction they are 
 analysed into their more simple elements ; 
 and the same may be said of the objects of 
 memory and of consciousness. 
 
 Secondly, Our most distinct complex 
 notions are those that are formed by com- 
 pounding the simple notions got by abstrac- 
 tion. 
 
 Thirdly, Without the powers of abstract- 
 ing and generalising, it would be impossible 
 to reduce things into any order and method, 
 by dividing them into genera and species. 
 
 Fourthly, Without those powers there 
 could be no definition ; for definition can 
 only be applied to universals, and no indi- 
 vidual can be defined. 
 
 Fifthly, Without abstract and general 
 notions there can neither be reasoning nor 
 language. 
 
 Sixthly, As brute animals shew no signs 
 of being able to distinguish the various 
 attributes of the same subject ; of being 
 able to class things into genera and species : 
 to define, to reason, or to communicate 
 their thoughts by artificial signs, as men 
 do — I must think, with Mr Locke, that they 
 have not the powers of abstracting and 
 generalising, and that, in this particular, 
 nature has made a specific difi'erence be- 
 tween them and the human species. 
 
 CHAPTER VI. 
 
 OPINIONS OF PHILOSOPHERS ABOUT 
 UNIVERSALS. 
 
 In the ancient philos()i)liy, the doctrine of 
 universals — that is, of tilings whicli we ex- 
 press by general terms — makes a great figure. 
 The ideas of the Pythagoreans and Pla- 
 tonists, of which so much has been already 
 said, were universals. [47fj] All science is 
 employed about universals as its object. 1 1 
 was thouglit that there can be no science, 
 unless its object be something real and 
 immutable ; and therefore those who paid 
 homage to truth and science, maintained 
 that ideas or universals have a real iind 
 immutable existence. 
 
 The sceptics, on the contrary, (for there 
 were sceptical jiliilosophers in tjiose early 
 days,) maintained that all things are mu- 
 table and in a perpetual fluctuation ; and, 
 from this principle, inferred that there is 
 [475-*77] 
 
 no science, no truth ; that all is uncertain 
 opinion. 
 
 Plato, and his masters of the Pythagorean 
 school, yielded this with regard to ol)jects 
 of sense, and acknowledged that there could 
 be no science or certain knowledge con- 
 cerning them. But they held that there 
 are objects of intellect of a superior order 
 and nature, which are permanent and im- 
 mutable. These are ideas, or universal 
 natures, of which the objects of sense are 
 only the images and shadows. 
 
 To these ideas they ascribed, as I have 
 already observed, the most magnificent 
 attributes. Of man, of a rose, of a circle, 
 and of every species of things, they believed 
 that there is one idea or form, which ex- 
 isted from eternity, before any individual of 
 the species was formed ; that this idea is 
 the exemplar or pattern, according to which 
 the Deity formed the individuals of the 
 species ; that every individual of the species 
 participates of this idea, which constitutes 
 its essence ; and that this idea is likewise 
 an object of the human intellect, when, by 
 due abstracti(m, we discern it to be one in 
 all the individuals of the species. 
 
 Thus the idea of every species, though 
 one and immutable, might be considered in 
 three different views or respects : Jirst, As 
 having an eternal existence before there 
 was any individual of the species ; secondly, 
 As existing in every individual of that spe- 
 cies, without division or multiplication, and 
 making the essence of the sjiecies ; and, 
 thirdly, As an object of intellect and of science 
 in man. [477] 
 
 Such I take to be the doctrine of Plato, 
 as far as I am able to comprehend it. His 
 disciple Aristotle rejected the first of these 
 views of ideas as visionary, but difl'ered 
 little from his master with regard to the 
 two last. He did not admit the existence 
 of universal natures antecedent to the ex- 
 istence of iiidividuals : but he held that 
 every individual consists of matter and 
 form ; that the form (which I take to be 
 what Plato calls the idea) is common to all 
 the individuals of the species ; and that the 
 human intellect is fitted to receive the forms 
 of things as objects of contem])lati()n. Such 
 profound speculations about the nature of 
 universals, we find even in the first ages of 
 philosophy* I wish I coulil make them 
 more intelligible to myself and to the reader. 
 
 The division of universals into five 
 classes — to wit, genus, sjiecies, specific 
 ditt'erence, properties, and accidents — is 
 likewise very ancient, and I conceive was 
 borrowed by the Peripatetics from the 
 Pythagorean school. + 
 
 * Difrorciit pliilosi |)her» h:.ve iiminliilncHl tint 
 Aristitlf was a Itr.-iliht, a ('<)llcc|ltuull^t, niid .1 Nii- 
 iii:ii»lii>t, 111 Hie stric iht 6C'ii-i'.— H. 
 
 \ I'liis |iri)(ir(th i> 1 llic «(i|i|icni'iiin llml ttir »ii|>- 
 I otilitiuui rylliitgorcaii trotiKCi arc gcniiiiK'. — II.
 
 406 
 
 ON THE INTKLLECTUAL POWERS. 
 
 [_ESSAY V. 
 
 Porphyry has given us a very distinct 
 treatise upon these, as an introduction to 
 Aristotle's categories. But he has omitted 
 the intricate metaphysical questions that 
 were agitated about their nature : such as, 
 whether genera and species do really exist 
 in nature, or whether they are only con- 
 ceptions of the human mind. If they exist 
 in nature, whether they are corporeal or 
 incorporeal ; and whether they are inherent 
 in the objects of sense, or disjoined from 
 them. These questions, he tells us, for 
 brevity's sake, he omits, because they are 
 very profound, and require accurate discus- 
 sion. It is probable that these questions 
 exercised the wits of the philosophers till 
 about the twelfth century. [478J 
 
 About that time, Roscelinus or Rusce- 
 linus, the master of the famous Abelard, 
 introduced a new doctrine — that there is 
 nothing universal but words or names. 
 For this, and other heresies, he was much 
 persecuted. However, by his eloquence 
 and abilities, and those of his disciple Abe- 
 lard, the doctrine spread, and those who 
 followed it were called Nominalists.* His 
 antagonists, who held that there are things 
 that are really universal, were called Realists. 
 The scholastic philosophers, from the be- 
 ginning of the twelfth century, were divided 
 into these two sects. Some few took a 
 middle road between the contending parties- 
 That universality which the Realists held 
 to be in things themselves. Nominalists in 
 names only, they held to be neither in things 
 nor in names only, but in our conceptions. 
 On this account they were called Concep- 
 tualists : but, being exposed to the batteries 
 of both the opposite parties, they made no 
 great figure. -f 
 
 When the sect of Nominalists was like 
 to expire, it received new life and spirit 
 from Occam, the disciple of Scotus, in the 
 fourteenth century. Then the dispute about 
 universals, a parte rei, was revived with 
 the greatest animosity in the schools of 
 Britain, France, and Germany, and carried 
 on, not by arguments only, but by bitter 
 reproaches, blows, and bloody affrays, until 
 the doctrines of Luther and the other Re- 
 formers turned the attention of the learned 
 world to more important subjects. 
 
 After the revival of learning, Mr Hobbes 
 adopted the opinion of the Nominalists.^: 
 
 * Abelard was not a Nominalist like Roscelinus; 
 but held a doctrine, intermediate between absolute 
 Nominalism and Realism, corresponding to the 
 opinion since called Conceptualism. A flood of light 
 has bei'n thrown upon Abelard's doctrines, hy M. 
 Cousin's introduction to his recent publication of 
 the unedited works of that illustrious thinker. — 
 H. 
 
 t The Liter Nominalists, of the school of Occam, 
 were really Conceptualists in our sense of the term. 
 — H. 
 
 t Hobbes is justly said by Leibnitz to have bicn 
 tpsif Nowinalibus nominalior. They were really 
 Conceptu alists.-. H , 
 
 " Human Nature," chap 5, § 6—" It is 
 plain, therefore," says he, "that there is no- 
 thing universal but names." And in his 
 " Leviathan," part i. chap 4, " There being 
 nothing universal but names, proper names 
 bring to mind one thing only ; universals 
 recall any one of many." 
 
 Mr Locke, according to the division be- 
 fore mentioned, I think, may be accounted 
 a Conceptualist. He does not maintain 
 that there are things that are universal ; 
 but that we have general or universal ideas 
 which we form by abstraction ; and this 
 power of forming abstract and general ideas, 
 he conceives to be that which makes the 
 chief distinction in point of understanding, 
 between men and brutes. [479] 
 
 Mr Locke's doctrine about abstraction 
 has been combated by two very powerful 
 antagonists. Bishop Berkeley and Mr Hume, 
 who have taken up the opinion of the Nom- 
 inalists. The former thinks, " That the 
 opinion that the mind hath a power of form- 
 ing abstract ideas or notions of things, has 
 had a chief part in rendering speculation 
 intricate and perplexed, and has occasioned 
 innumerable errors and difficulties in almost 
 all parts of knowledge." That " abstract' 
 ideas are like a fine and subtile net, which 
 has miserably perplexed and entangled the 
 minds of men, with this peculiar circum- 
 stance, that by how much the finer and 
 more curious was the wit of any man, by 
 so much the deeper was he like to be en- 
 snared, and faster held therein." That, 
 " among all the false principles that have 
 obtained in the world, there is none hath a 
 more wide influence over the thoughts of 
 speculative men, than this of abstract gene- 
 ral ideas." 
 
 The good bishop, therefore, in twenty- 
 four pages of the introduction to his " Prin- 
 ciples of Human Knowledge," encoimters 
 this principle with a zeal proportioned to 
 his apprehension of its malignant and ex- 
 tensive influence. 
 
 That the zeal of the sceptical philosopher 
 against abstract ideas was almost equal to 
 that of the bishop, appears from his words, 
 " Treatise of Human Nature," Book I. 
 part i. § 7 : — " A very materi.al question 
 has been started concerning abstract or 
 general ideas — whether they be general or 
 particular, in the mind's conception of them. 
 A great philosopher" (he means Dr Berke- 
 ley) " has disputed the received opinion in 
 this particular, and has asserted that all 
 general ideas are nothing but particular ones 
 annexed to a certain term, which gives them 
 a more extensive signification, and makes 
 them recall, upon occasion, other individuals 
 which are similar to them. As I look upon 
 this to be one of the greatest and most 
 valuable discoveries that have been made 
 of Ittte years in the republic of letters, 1 
 
 [478, 4-791
 
 CHAP. VI.] 
 
 OPINIONS ABOUT qNIVERSALS. 
 
 407 
 
 ehall here endeavour to confirm it by some 
 arguments, which, I hope, will put it beyond 
 all doubt and controversy." [480] 
 
 I shall make an end of this subject, with 
 some reflections on what has been said upon 
 it by these two eminent philosophers. 
 
 1. First, I apprehend that we cannot, 
 with propriety, be said to have abstract and 
 general ideas, either in the popular or in the 
 philosophical sense of that word. In the 
 popular sense, an idea is a thought ; it is 
 the act of the mind in thinking, or in con- 
 ceiving any object. This act of the mind 
 is always an individual act, and, therefore, 
 there can be no general idea in this sense. 
 In the philosophical sense, an idea is an 
 image in the mind, or in the brain, which, 
 in Mr Locke's system, is the immediate ob- 
 ject of thought ; in the system of Berkeley 
 and Hume, the only object of thought. I 
 believe there are no ideas of this kind, and, 
 therefore, no abstract general ideas. In- 
 deed, if there were really such images in 
 the mind or in the brain, they could not 
 be general, because everything that really 
 exists is an individual. Universals are 
 neither acts of the mind, nor images in the 
 mind. 
 
 As, therefore, there are no general ideas 
 in either of the senses in which the wm-d 
 idea is used by tlie moderns, Berkeley and 
 Hume have, in this question, an advantage 
 over Mr Locke ; and their arguments against 
 him are good ad Imminem. They saw 
 farther than he did into the just conse- 
 quences of the hypothesis concerning ideas, 
 which was common to them and to him ; 
 and they reasoned justly from this hypo- 
 thesis when they concluded from it, that 
 there is neither a material world, nor any 
 such power in the human mind as that of 
 abstraction, [481] 
 
 A triangle, in general, or any other uni- 
 versal, might be called an idea by a Plato- 
 nist ; but, in the style of modern i)hilo- 
 sopliy, it is not an idea, nor do we ever 
 ascribe to ideas the properties of triangles. 
 It is never said of any idea, that it has 
 three sides and three angles. We do not 
 speak of equilateral, isosceles, or scalene 
 ideas, nor of right-angled, acute-angled, or 
 obtuse-angled ideas. And, if these attri- 
 butes do not belong to ideas, it follows, 
 necessarily, that a triangle is not an iilea. 
 The same reasoning may be applied to 
 every other universal. 
 
 Ideas are said to have a real existence in 
 the mind, at least while we think of tliem ; 
 but universals have no real existence. 
 When we ascribe existence to them, it is 
 not an existence in time or [)lacc, imt exist- 
 ence in some individual sulijcct ; and this 
 existence means no more but that tlu^y are 
 truly attributes of such a Hubj<,'ct. 'J'licir 
 existence is nothing Imt prfdicability, or the 
 [ iSO-iS^] 
 
 capacity of being attributed to a subject. 
 The name of predieables, which was given 
 them in ancient philosojihy, is that which 
 most properly expresses their nature. 
 
 2. I think it must be granted, in the 
 second place, that universals cannot be the 
 objects of imagination, when we take that 
 word in its strict and proper sense. '* I 
 find," says Berkeley, " I have a faculty of 
 imagining or representing to myself the 
 ideas of those particular tilings I liave per- 
 ceived, and of variously compounding and 
 dividing them. I can imagine a man with 
 two heads, or the upper parts of a man 
 jomed to the body of a horse. I can imagine 
 the hand, the eye, the nose, each by itself, 
 abstracted or separated from the rest of the 
 body. But then, whatever liuiul or eye I 
 imagine, it nuist have some particular shape 
 or colour. Likewise, the idea of a man that 
 I frame to myself nuist be either of a white, 
 or a black, or a tawny ; a straight or a 
 crooked ; a tall, or a low, or a middle-sized 
 man." 
 
 I believe every man will find in himself 
 what this ingenious author found — that he 
 cannot imagine a man without colour, or 
 stature, or shape. [482] 
 
 Imagination, as we before observed, pro- 
 perly signifies a conception of the appear- 
 ance an object wouUl make to the eye if 
 actually seen." An universal is not an 
 object of any external sense, and therefore 
 cannot be imagined ; but it may be dis- 
 tinctly conceived. When Mr Pope says, 
 " The proper study of mankind is man," I 
 conceive his meaning distinctly, though I 
 neither imagine a black or a white, a 
 crooked or a straight man. Tlie distinction 
 between conce])tion and imagination is real, 
 though it be too often overlooked, and the 
 words taken to be .synoninious. I can con- 
 ceive a thing that is impossible,-)- but I 
 cannot distinctly imagine a thing that is 
 imjiossible. I can conceive a proposition or 
 a demonstration, but I cannot imagine 
 either. I can conceive understanding and 
 will, virtue and vice, and other attributes of 
 mind, but 1 cannot imagine them. In like 
 manner, I can distinctly conceive uni- 
 versals, but I cannot imagine theni.:|: 
 
 As to the manner how we conceive uni- 
 versals, I confess my ignorance. I know 
 not how I hear, or see, or remember, and 
 as little do I know how I conceive things 
 that have no existence. In all our original 
 
 * See above, p. :Wi, a, iioic— H. 
 
 t .Ste above, p. .'fTT, I), iioti'.— II. 
 
 % IinaRin.itiDii niid Concept iiiii ari> dislinciiiiihcd, 
 but tlic latter Mm\\l not to lie used in the vanue and 
 extenkive kiKMiCieatiiin o( Ueiil. Tlie (lii,eriiniii;iliiin 
 in (|uestic>n is liest made in the Gcriiiaii lnii|{ini|(0 of 
 philciMipliy, where tlietermn JiiyrilK' (Cnneeptioin) 
 are utroniily conlrnMed with Aiiiirniiiiiiiiiii-ii (Iiitul. 
 tionii), llililiii (liiiMKen), *<C SeenlKive, p.:«fl,n, noir 
 1 ; |>. :)Ci.'). I>, note j. Ill' reiidei ni.iy loiiip.irB 
 ."^tewanV" K oinenlt," I. p. ilCi. — H.
 
 408 
 
 ON THE INTELLECTUAL POWERS. 
 
 [essay 
 
 faculties, the fabric and manner of operation 
 is, I apprehend, beyond our comprehension, 
 and perhaps is perfectly understood by him 
 only who made them. 
 
 But we ought not to deny a fact of which 
 we are conscious, though we know not how 
 it is brought about. And I think we may 
 be certain that universals are not conceived 
 by means of images of them in our minds, 
 because there can be no image of an uni- 
 versal. 
 
 3. It seems to me, that on this question 
 Mr Locke and his two antagonists have 
 divided the truth between them. He saw 
 very clearly, that the power of forming ab- 
 stract and general conceptions is one of tlie 
 most distinguishing powers of the human 
 mind, and puts a specific difference between 
 man and the brute creation. But he did 
 not see that this power is perfectly irrecon- 
 cileable to his doctrine concerning ideas. 
 [483] 
 
 His opponents saw this inconsistency ; 
 but, instead of rejecting the hypothesis of 
 ideas, they explain away the power of ab- 
 straction, and leave no specific distinction 
 between the human understanding and that 
 of brutes. 
 
 4. Berkeley," in his reasoning against 
 abstract general ideas, seems unwillingly 
 or unwarily to grant all that is necessary 
 to support abstract and general concep- 
 tions. 
 
 '' A man," he says, " may consider a 
 figure merely as triangular, without attend- 
 ing to the particular qualities of the angles, 
 or relations of the sides So far he may 
 abstract. But this will never prove that 
 he can frame an abstract general inconsist- 
 ent idea of a triangle." 
 
 If a man may consider a figure merely 
 as triangular, he must have some concep- 
 tion of this object of his consideration ; for 
 no man can consider a thing which he dues 
 not conceive. He has a conception, there- 
 fore, of a triangular figure, merely as such. 
 I know no more that is m i.mt by an abstract 
 general conception of a triangle. 
 
 He that considers a figure n.erely as tri- 
 angular, must understand what is meant by 
 the word triangular. If, to the conception 
 he joins to this word, he adds any particu- 
 lar quality of angles or relation of sides, he 
 misunderstands it, and does not consider 
 the figure merely as triangular. Whence, 
 I think, it is evident, that he who considers 
 a figure merely as triangular must have the 
 conception of a triangle, abstracting from 
 any quality of angles or relation of sides. 
 
 The Bishop, in like manner, grants, 
 " That we may consider Peter so far forth 
 as man, or so far forth as animal, without 
 
 * On Reid's critici-m of Berkeley, see Stewart, 
 {Ekmentt, II. p. 110, *q.)— H. 
 
 framing the forementioned abstract idea, in 
 as much as all that is perceived is not 
 considered." It may here be observed, 
 that he who considers Peter so far forth as 
 man, or so far forth as animal, must con- 
 ceive the meaning of those abstract general 
 words man and animal, and he who con- 
 ceives the meaning of them has an abstract 
 general conception. [484] 
 
 From these concessions, one would be 
 apt to conclude that the Bishop thinks that 
 we can abstract, but that we cannot frame 
 abstract ideas ; and in this I should agree 
 with him. But I cannot reconcile his con- 
 cessions with the general principle he lavs 
 down before. " To be plain," says he, '' I 
 deny that I can abstract one from another, 
 or conceive separately those qualities which 
 it is impossible should exist so separated." 
 This appears to me inconsistent with the 
 concessions above mentioned, and incon- 
 sistent with experience. 
 
 If we can consider a figure merely as 
 triangular, without attending to the parti- 
 cular quality of the angles or relation of the 
 sides, this, I think, is conceiving separately 
 things which cannot exist so separated : 
 for surely a triangle cannot exist without 
 a particular quality of angles and relation 
 of sides. And it is well known, from ex- 
 perience, that a man may have a distinct 
 conception of a triangle, without having 
 any conception or knowledge of many of 
 the properties without which a triangle 
 cannot exist. 
 
 Let us next consider the Bishop's notion 
 of generalising.* He does not absolutely 
 deny that there are general ideas, but only 
 that there are abstract general ideas. "An 
 idea," he says, " which, considered in it- 
 self, is particular, becomes general, by be- 
 ing made to represent or stand for all other 
 particular ideas of the same sort. To make 
 this plain by an example : Suppose a geo- 
 metrician is demonstrating the method of 
 cutting a line in two equal parts. He 
 draws, for instance, a black line, of an inch 
 in length. This, which is in itsilf a parti- 
 cular line, is, nevertheless, with regard to 
 its signification, general ; since, as it is 
 there used, it represents all particular lines 
 whatsoever ; so that what is demonstrated 
 of it, is demonstrated of all lines, or, in 
 other words, of a line in general. And as 
 that particular line becomes general by be- 
 ing made a sign, so the name line, which, 
 taken absolutely, is particular, by being a 
 sign, is made general." [485] 
 
 Here I observe, that when a particular 
 idea It made a sign to represent and stand 
 for all of a sort, this supposes a distinction 
 of things into sorts or ppecies. To be of a 
 sort implies having those attributes which 
 
 * See Stewart, {Elements, II p. 126.)— H. 
 
 [t83-485]
 
 CHAP. VI.] 
 
 OPINIONS ABOUT UNIVERSALS. 
 
 409 
 
 characterise tlie sort, and are common to 
 all the individuals that belong to it There 
 cannot, therefore, be a sort without general 
 attributes, nor can there be any conception 
 of a sort without a conception of those 
 general attributes which distinguish it The 
 conception of a sort, therefore, is an ab- 
 stract general conception. 
 
 The particular idea cannot surely be made 
 a sign of a thing of wliich we have no con- 
 ception. I do not say that you must have 
 
 an idea of the sort, but ^ui-el} 
 
 oui;ht 
 
 to understand or conceive what it means, 
 when you make a particular idea a repre- 
 sentative of it ; otherwise your particular 
 idea represents, you know not what 
 
 When I demonstrate any general pro- 
 perty of a triangle, such as, that the three 
 angles are equal to two right angles, I must 
 understand or conceive distinctly what is 
 common to all triangles. I must distinguish 
 the common attributes of all triangles from 
 those wherein particular triangles may differ. 
 And, if I conceive distinctly what is common 
 to all triangles, without confounding it with 
 what is not so, this is to form a general con- 
 ception of a triangle. And without this, it 
 is impossible to know that the demonstra- 
 tion extends to all triangles. 
 
 The Bishop takes particularnotice of this 
 argument, and makes this answer to it : — 
 •' Though the idea I have in view, whilst 
 I make the demonstration, be, for instance, 
 that of an isosceles rectangular triangle, 
 whose sides are of a determinate length, I 
 may nevertheless be certain that it extends 
 to all other rectilinear triangles, of what 
 sort or bigness soever ; and that because 
 neither the right angle, nor the equality or 
 determinate length of the sides, are at all 
 concerned in the demonstration." [480] 
 
 But, if he do not, in the idea he has in 
 view, clearly distinguish what is common 
 to all triangles from what is not, it would 
 be impossible to discern whether something 
 that is not common be concerned in the 
 demonstration or not. In order, therefore, 
 to perceive that the demonstration extends 
 to all triangles, it is necessary to have a 
 distinct conception of what is common to 
 all triangles, excluding from that concep- 
 tion all that is not common. And this is 
 all I understauil by an abstract general 
 conception of a triangle. 
 
 Berkeley catches an advantage to his side 
 of the question, from what Mr Locke ex- 
 presses (too strongly indeed) of the difficulty 
 of framing abstract general ideas, and the 
 pains and skill necessary for that purpose. 
 From which tlie Bishop infers, that a thing 
 so dilKeult cannot be necessary for com- 
 munication ljy language?, which is so easy 
 and familiar to all sorts of men. 
 
 There may be some abstract ami general 
 conceptioHH that are difficult, or even bc- 
 
 yond the reach of persons of weak under- 
 standing ; but there are innumerable which 
 are not beyond the reach of children. It 
 is impossible to learn language witliout 
 acquiring general conceptions ; for there 
 cannot be a single sentence without them. 
 I believe the forming these, and being able 
 to articulate the sounds of language, make 
 up the whole difficulty that children find in 
 learning language at first. 
 
 But this difficulty, we see, they are able 
 to overcome so early as not to remember 
 the pains it cost them. They have the 
 strongest inducement to exert all their 
 labour and skill, in order to understand 
 and to be understood ; and they no doubt 
 do so. [487] 
 
 The labour of forming abstract notions, is 
 the labour of learning to sjieak, and to 
 understand what is spoken. As the words 
 of every language, excepting a few proper 
 names, are general words, the minds of 
 children are furnished witli general con- 
 ceptions, in proportion as they learn the 
 meaning of general words. I believe most 
 men have hardly any general notions but 
 those which are expressed by the general 
 words they hear and use in conversation. 
 The meaning of some of these is learned 
 by a definition, wliich at once conveys a 
 distinct and accurate general conception. 
 The meaning of other general words we 
 collect, by a kind of induction, from the 
 way in which we see them used on various 
 occasions by those who understand the 
 language. Of these our conception is often 
 less distinct, and in different persons is 
 perhaps not perfectly the same. 
 
 " Is it not a hard thing," says the Bishop, 
 "that a couple of children cannot prate to- 
 gether of their sugar-iilumbs and rattles, 
 and the rest of their little trinkets, till they 
 have first tacked together numberless in- 
 consistencies, and so formed in their minds 
 abstract general ideas, and annexed them 
 to every connnon nann; they make use of?" 
 
 However liard a thing it may be, it is an 
 evident truth, that a couple of children, 
 even about their sugar- plumbs a:id their 
 rattles, cannot prate so as to understand 
 and be understood, until they have learned 
 to conceive the meaning of many general 
 words — and this, I think, is to have general 
 concei)tions. 
 
 5. Having considered the sentiments of 
 Bishop Jk-rlcclcy on this suljcft, let us 
 next attend to tliose of Mr lliime, as they 
 are expressed Part I. § 7, " Treatise of 
 Human Nature." He agrees perfectly 
 with the Bishop, " That all general ideas 
 are nothing but particular ones annexeil to 
 a certain term, which gives them a more 
 extensive signification, and makes thi-m 
 recall, upon occasion.othi-rinilividiials which 
 are similar to them. [JUllj A particular
 
 410 
 
 ON THE INTELLECTUAL POWERS. 
 
 [essay v. 
 
 idea becomes general, by being annexed to 
 a general term ; that is, to a term, which, 
 from a customary conjunction, has a rela- 
 tion to many other particular ideas, and 
 readily recalls them in the imagination. 
 Abstract ideas are therefore in themselves 
 individual, however they may become general 
 in their representation. The image in the 
 mind is only that of a particular object, 
 though the application of it in our reason- 
 ing be the same as if it was universal." 
 
 Although Mr Hume looks upon this to 
 be one of the greatest and most valuable 
 discoveries that has been made of late years 
 in the republic of letters, it appears to be 
 no other than the opinion of the nominal- 
 ists, about which so much dispute was 
 held from the beginning of the tweltth 
 century down to the Reformation, and 
 which was afterwards supported by Mr 
 Hobbes. I shall briefly consider the argu- 
 ments by which Mr Hume hopes to have 
 put it beyond all doubt and controversy. 
 
 First, He endeavours to prove, by three 
 arguments, that it is utterly impossible to 
 conceive any quantity or quality, without 
 forming a precise notion of its degrees; 
 
 This is indeed a great undertaking ; but, 
 if he could prove it, it is not sufficient for 
 his purpose — for two reasons. 
 
 First, Because there are many attributes 
 of things, besides quantity and quality ; and 
 it is incumbent upon him to prove that it 
 is impossible to conceive any attribute, 
 without forming a precise notion of its 
 degree. Each of the ten categories of 
 Aristotle is a genus, and may be an attri- 
 bute. And, if he should prove of two of 
 them — to wit, quantity and quality— that 
 there can be no general conception of them ; 
 there remain eight behind, of which this 
 must be proved. [489] 
 
 The other reason is, because, though it 
 were impossible to conceive any quantity 
 or quality, without forming a precise notion 
 of its degree, it does not follow that it is 
 impossible to have a general conception 
 even of quantity and quality. The con- 
 ception of a pound troy is the conception 
 of a quantity, and of the precise degree of 
 that quantity ; but it is an abstract general 
 conception notwithstanding, because it may 
 be the attribute of many individual bodies, 
 and of many kinds of bodies. He ought, 
 therefore, to have proved that we cannot 
 conceive quantity or quality, or any other 
 attribute, without joining it inseparably to 
 some individual subject. 
 
 This remains to be proved, which will be 
 found no easy matter. For instance, I 
 conceive what is meant by a Japanese as 
 distinctly as what is meant by an English- 
 man or a Frenchman. It is true, a Japan- 
 ese is neither quantity nor quality, but it 
 is an attribute common to every individual 
 
 of a populous nation. I never saw an in- 
 dividual of that nation ; and, if I can trust 
 my consciousness, the general term does 
 not lead me to imagine one individual of 
 the sort as a representative of all others. 
 
 Though Mr Hume, therefore, undertakes 
 much, yet, if he could prove all he under- 
 takes to prove, it would by no means be 
 sufficient to shew that we have no abstract 
 general conceptions. 
 
 Passing this, let us attend to his argu- 
 rneiits for proving this extraordinary posi- 
 tion, that it is impossible to conceive any 
 quantity or quality, without forming a pre- 
 cise notion of its degree. 
 
 The first argument is, that it is impossi- 
 ble to distinguish things that are not ac- 
 tually separable. " The precise lenstii of 
 a line is not different or distinguishable 
 from the line." [490] 
 
 I have before endeavoured to shew, that 
 things inseparable in their nature may be- 
 distinguished in our conception. And we 
 need go no farther to be convinced of this, 
 than the instance here brought to prove 
 tlie contrary. The precise length of a line, 
 he says, is not distinguishable from the 
 line. When I say. This is a line, I say and 
 mean one thing. When I say. It is a line 
 of three inches, I say and mean another 
 thing. If this be not to distinguish the 
 precise length of the line from the line, I 
 know not what it is to distinguish. 
 
 Second argument — " Every object of 
 sense — that is, every impression — is an in- 
 dividual, having its determinate degrees of 
 quantity and quality. But whatever is 
 true of the impression is true of the idea, 
 as they differ in nothing but their strength 
 and vivacity." 
 
 The conclusion in this argument is, in- 
 deed, justly drawn from the premises. If 
 it be true that ideas diff"er in nothing from 
 objects of sense, but in strength and viva- 
 city, as it must be granted that all the ob- 
 jects of sense are individuals, it will cer- 
 tainly follow that all ideas are individuals. 
 Granting, therefore, the justness of this 
 conclusion, I beg leave to draw two other 
 conclusions from the same premises, which 
 will follow no less necessarily. 
 
 First, If ideas diff"er from the objects of 
 sense only in strength and vivacity, it will 
 follow, that the idea of a lion is a lion of 
 less strength and vivacity. And hence may 
 arise a very important question. Whether 
 the idea of a lion may not tear in pieces, 
 and devour the ideas of sheep, oxen, and 
 horses, and even of men, women, and 
 children ? 
 
 Secoiidh/, If ideas diff'er only in strength 
 and vivacity from the objects of sense, it 
 will follow that objects merely conceived, 
 are not ideas ; for such objects diff"er from 
 the objects of sense in respects of a very 
 
 [4.89, 490]
 
 CHAP. Vl.^ 
 
 OPINIONS ABOUT UNI VERSA LS. 
 
 411 
 
 different nature from strength and vivacity. 
 [491] Every object of sense must have a 
 real existence, and time and place. But 
 things merely conceived may neither have 
 existence, nor time nor place ; and, there- 
 fore, though there should be no abstract 
 ideas, it does not follow that things abstract 
 and general may not be conceived. 
 
 The third argument is this : — " It is a 
 principle generally received in philosophy, 
 that everything in nature is individual ; and 
 that it is utterly absurd to suppose a tri- 
 angle really existent which has no precise 
 proportion of sides and angles. If this, 
 therefore, be absurd in fact and reality, it 
 must be absurd in idea, since notliing of 
 which we can form a clear and distinct 
 idea is absurd or impossible." 
 
 I acknowledge it to be impossible that a 
 triangle should really exist wjiich has no 
 precise proportion of sides and angles ; and 
 impossible that any being should exist 
 which is not an individual being ; for, I 
 think, a being and an individual being 
 mean the same thing : but that there can 
 be no attributes common to many indivi- 
 duals I do not acknowledge. Thus, to 
 many figures that really exist it may be 
 common that they are triangles ; and to 
 many bodies that exist it may be common 
 that they are fluid. Triangle and fluid are 
 not beings, they are attributes of beings. 
 
 As to the principle here assumed, that 
 nothing of which we can form a clear and 
 distinct idea is absurd or impossible, I refer 
 to what was said upon it, chap. 3, Essay 
 IV. It is evident that, in every mathema- 
 tical demonstration, ad ahsunlnm, of which 
 kind almost one-half of mathematics con- 
 sists, we are required to sujiposc, and, con- 
 sequently, to conceive, a thing that is im- 
 possible. From that supposition we reason, 
 until we come to a conclusion that is not 
 only impossible but absurd. From this we 
 infer that the proposition supposed at first 
 is impossible, and, therefore, that its con- 
 tradictory is true. [492] 
 
 As this is the nature of all demonstra- 
 tions, ad a'usurdum, it is evident, (I do not 
 say that we can have a clear and distinct 
 idea,) but that we can clearly and distinctly 
 conceive things impossible. 
 
 The rest of I\Ir Hume's discourse uj)()n 
 this subject is employed in explaining how 
 an individual idea, annexed to a general 
 term, may serve all the purposes in reason- 
 ing which have been ascribed to abstract 
 general idcis 
 
 " Wlien we have found a resemblance 
 among several objects that often occur to 
 us, we ajjply the same name to all of theni, 
 whatever differences we may observe in the 
 degrees of their quantity and quality, and 
 whatever other diflerences may appear 
 among theui. Afler we hrivc acqiiind :i 
 [4Sl-4ft.Sl 
 
 custom of this kind, the hearing of that 
 name revives the idea of one of these ob- 
 jects, and makes the imagination conceive 
 it, with all its circumstances and propor- 
 tions." But, along with this idea, there is 
 a readiness to survey any other of the indi- 
 viduals to which the name belongs, and to 
 observe that no conclusion be fonned con- 
 trary to any of tli( in. If any such conclu- 
 sion is formed, those individual ideas which 
 contradict it immediately crowd in upon us, 
 and make us perceive the lalschood of tlie 
 proposition. If the mind suggests not al- 
 ways these ideas upon occasion, it proceeds 
 from some imperfection in its faculties ; 
 and such a one as is often the source of 
 false reasoning and sophistry. 
 
 This is, in substance, the way in which 
 he accounts for what he calls " the fore- 
 going paradox, that some ideas are parti- 
 cular in their nature, but general in their 
 representation." Upon this account I shall 
 make some remarks. [493] 
 
 1. He allows that we find a resemblance 
 among several objects, and such a resem- 
 blance as leads us to apply the same name 
 to all of them. This concession is suffi- 
 cient to shew that we have general concep- 
 tions. There can he no resemblance ii» 
 objects that have no common attribute; 
 and, if there be attributes belonging in com- 
 mon to several objects, and in man a fa- 
 culty to observe and conceive these, and to 
 give names to them, this is to have general 
 conceptions. 
 
 I believe, indeed, we may have an indis- 
 tinct perception of resemblance without 
 knowing wherein it lies. Thus, I may see 
 a resemblance between one face and an- 
 other, when 1 cannot distinctly say in what 
 feature they resemble ; but, by analysing 
 the two faces, and comparing feature with 
 feature, I may form a distinct notion of 
 that which is common to both, A painter, 
 being accustomed to an analysis of this kind, 
 would have formed a distinct notion of this 
 resemblance at iirst sight ; to another num 
 it may require some attention. 
 
 There is, therefore, an indistinct notion 
 of resemblance when we compare the objects 
 only in gross : and this 1 believe brute ani- 
 mals nuiy have. There is also a distinct 
 notion of resemblance wIkmi we analyse the 
 objects into their ditl'erent attrilmtcs, and 
 perceive them to agree in some while they 
 differ in others. It is in this case only that 
 we give a name to the attributes wherein 
 they agree, whicli must be a common n:inie, 
 because the thing sigiufied by it is common. 
 'J'luis, when I compare cubes of dilfetcnt 
 matter, I perceive them to have this iitiri- 
 bute in common, that they are compro- 
 bended under six ciiual s(imiri's and this 
 attribute only is signitiid by applying the 
 name or<v(A,"t() them all. Whrn I com-
 
 412 
 
 ON THE INTELLF>CTUAL POWERS. 
 
 [essa V 
 
 pare clean linen with snow, I perceive them 
 to agree in colour ; and when I apply the 
 name of white to both, this name signifies 
 neither snow nor clean linen, but the attri- 
 bute which is common to both. 
 
 2. The author says, that when we have 
 found a resemblance among several objects, 
 we apply the same name to all of them. 
 [494] 
 
 It must here be observed, that there are 
 two kinds of names which the author seems 
 to confound, though they are very diiferent 
 in nature, and in the power they have in 
 language. There are proper names, and 
 there are common names or appellatives. 
 The first are the names of individuals. Tlie 
 same proper name is never applied to 
 several individuals on account of their simi- 
 litude, because the very intention of a pro- 
 per name is to distinguish one individual 
 from all others ; and hence it is a maxim 
 in grammar that proper names have no 
 plural number. A proper name signifies 
 nothing but the individual whose name it 
 is ; and, when we apply it to the individual, 
 we neither affirm nor deny anything con- 
 cerning him. 
 
 A common name or appellative is not the 
 name of any individual, but a general term, 
 signifying something that is or may be 
 common to several ir.dividuals. Common 
 names, therefore, signify common attri- 
 butes. Thus, when I apply the name of 
 son or brother to several persons, this sig- 
 n'fies and affirms that this attribute is 
 common to all of them. 
 
 From this, it is evident that the apply- 
 ing the same name to several individuals 
 on account of their resemblance, can, in 
 consistence with grammar and common 
 sense, mean nothing else than the express- 
 ing, by a general term, something tliat is 
 common to those individuals, and which, 
 therefore, may be truly affirmed of them all. 
 
 3. The author says, "It is certain that 
 we form the idea of individuals whenever 
 we use any general term. The word raises 
 up an individual idea, and makes the ima- 
 ghmtion conceive it, with all its particular 
 circumstances and proportions." 
 
 This fact he takes a great deal of pains to 
 account for, from the effect of custom. 
 [495] 
 
 But the fact should be ascertained before 
 we take pains to account for it, I can see 
 no reason to believe the fact ; and I think 
 a farmer can talk of his sheep and his black 
 cattle, without conceiving, in his imagina- 
 tion, one individual, with all its circum- 
 stances and proportions. If this be true, 
 the whole of his theory of general ideas falls 
 
 to the ground. To me it appears, that 
 when a general term is well understood, it is 
 only by accident if it suggest some indi- 
 vidual of the kind; but this effect is by no 
 means constant. 
 
 I understand perfectly what mathemati- 
 cians call a line of the fifth order ; yet I 
 never conceived in my imagination any one 
 of the kind in all its circumstances and pro- 
 portions. Sir Isaac Newton first formed a 
 distinct general conception of lines of the 
 tliird order ; and afterwards, by great labour 
 and deep penetration, found out and de- 
 scribed the particular species comprehended 
 under that general term. According to Mr 
 Hume's theory, he must first have been 
 acquainted with the particulars, and then 
 have learned by custom to apply one 
 general name to all of them. 
 
 The author observes, " That the idea of 
 an equilateral triangle of an inch perpen- 
 dicular, may serve us in talking of a figure, 
 a rectilinear figure, a regular figure, a tri- 
 angle, and an equilateral triangle. " 
 
 T answer, the man that uses these general 
 terms either understands their meaning, 
 or he does not. If he does not understand 
 their meaning, all his talk about them will 
 be found only without sense, and the par- 
 ticular idea mentioned cannot enable him 
 to speak of them with understanding. If 
 he understands the meaning of the general 
 terms, he will find no use for the particular 
 idea. 
 
 4. He tells us gravely, " That in a globe 
 of white marble the figure a: id the colour 
 are undistinguishable, and are in effect the 
 same," [496] How foolish have mankind 
 been to give different names, in all ages 
 andin all languages, to things undistinguish- 
 able, and in effect tliesame ? Henceforth, 
 in all books of science and of entertainment, 
 we may substitute figure fur colour, and 
 colour for figure. By this we shall make 
 numberless curious discoveries, without 
 danger of error. * [497] 
 
 * The whole controversy ot Nominalism and Con- 
 ceptualisra is founded on the arnbit;uiiy of the terms 
 employed. The oiiposite pariiis are substantially at 
 one. Hart our British phiiosopherg been aware of 
 the Leibriitzian distinction o( lutiiilive and Sy»iboli- 
 cal knowlcdg ; and had we, like (he Germans, 
 dilfi-rent terms, like Beyriff a.' dAnschaminri, to de 
 note different kinds ot thought, there wniild have 
 bein as little ditfc-rence of opinion in regard to tlie 
 natuie of general n tions in this country as in the 
 Empire, with us. Idea, Notion, Conceition, ^^. 
 are confounded, or applied by dirfcreni phnosophirs 
 I in different si uses. 1 must put the reader on his 
 guard against J)r Thomas brown's sp cidaiions on 
 this subject. His own doctrine of universals, in so 
 far as It IS peculiar, is self-c ntradictory ; and nothing 
 can be more erroneous than his statement of the doc- 
 trine held by others, especially by the Nominalists. 
 — H, 
 
 [494-497]
 
 THAP. 1."] 
 
 OF JUDGMENT IN GENERAL. 
 
 413 
 
 ESSAY VI. 
 
 OF JUDGMENT 
 
 CHAPTER I. 
 
 OF JUDGMENT IN GENERAL. 
 
 Judging is an operation of the mind so 
 familiar to every man who hath understand- 
 ing, and its name is so common and so well 
 understood, that it needs no definition. 
 
 As it is impossible by a definition to give 
 a notion of colour to a man who never saw 
 colours ; so it is impossible by any defini- 
 tion to give a distinct notionof judgment to 
 a man who has not often judged, and who 
 is not capable of reflecting attentively upon 
 this act of his mind. The best use of a de- 
 finition is to prompt him to that reflection ; 
 and without it the best definition will be apt 
 to mislead him. 
 
 The definition commonly given of judg- 
 ment, by the more ancient writers in logic, 
 was, that it is an act of the mind, tvhereiy 
 onothirifi is affirmed or denied of another. 
 I believe this is as good a definition of it as 
 can be given. Why I prefer it to some 
 later definitions, will afterwards appear. 
 Without pretending to give any other, / 
 shall make two remarks upon it, and then 
 offer some general observations on this 
 subject. [498] 
 
 1- It is true that it is by aflSrmation or 
 denial that we express our judgments ; but 
 there may be judgment which is not ex- 
 pressed. It is a solitary act of the mind, 
 and the expression of it by affirmation or 
 denial is not at all essential to it. It may 
 be tacit, and not expressed. Nay, it is 
 well known that men may judge contrary 
 to what they affirm or deny ; the definition 
 therefore must be understood of mental af- 
 firmation or denial, which indeed is only 
 another name for juugment. 
 
 2. Atrirniation and denial is very often 
 the expression of testimony, which is a dif- 
 ferent act of the mind, and ought to be 
 distinguished from judgment. 
 
 A judge asks of a witness what he knows 
 of such a matter to which he was an eye 
 or ear-witness. He answers, by aftirming 
 or denying something But his answer 
 does not express his judgment; it is his 
 testimony. Again, I ask a man Iiisoj inion 
 in a matter of science or of criticrism. His 
 answer is not testimony ; it is the expres 
 sion of his judgment. 
 
 'I'cstimony is a social .act, and it is essen 
 [498, 4-99] 
 
 tial to it to be expressed by words or signs. 
 A tacit testimony is a contradiction : but 
 there is no contradiction in a tacit judgment; 
 it is complete without being expressed. 
 
 In testimony a man pledges his veracity 
 for what he affirms ; so that a false testi- 
 mony is a lie : but a wrong judgment is not 
 a lie ; it is only an error. 
 
 I believe, in all languages, testimony and 
 judgment are expressed by the same form 
 of speech. A proposition affirmative or 
 negative, with a verb in wh."it is called the 
 indicative mood, expresses both. To dis- 
 tinguish them by the form of speech, it 
 would be necessary that verbs sli^uld have 
 two indicative moods, one for testimony, 
 and another to express judgment. [499] 
 I know not that this is found in any lan- 
 guage. And the reason is — not surely that 
 the vulgar cannot distinguish the two, for 
 every man knows the ditt'erencc between a 
 lie and an error of judgment — but that, from 
 the matter and circumstances, we can easily 
 see whether a man intends to give his tes- 
 timony, or barely to express his judgment. 
 
 Although men must have judged in many 
 cases before tribunals of justice were 
 erected, yet it is very probable that there 
 were tribunals before men began to specu- 
 late about judgment, and that the word may 
 be borrowed from the i)ractice of tribunals. 
 As a judge, after taking the proper evidence, 
 piisses sentence in a cause, and that sent- 
 ence is called his judgment, so the mind, 
 with regard to whatever is true or false, 
 passes sentence, or determines according to 
 the evidence that apjiears. Some kinds of 
 evidence leave no mom for doubt. Sent- 
 ence is passed immediately, without seek- 
 ing or hearing any contrary evidence, 
 because the thing is certain and notoiious. 
 In other cases, there is room for weighing 
 evidence on both sides, bi fore sentence is 
 passed. The analogy between a tribunal 
 of justice, and tlii.^ inward trilmnal of the 
 mind, is too obvidus to escape the notice of 
 any man who ever appeared bel'dro a jtulge. 
 yVnd it is probable that tlie word jiidi/wen', 
 as well asniany other words we use in 8|>c:iK- 
 ing of this ojk ration of miml, are grounded 
 on this analii;:y. 
 
 Having premised these things, that it 
 ni.'iy be clearly undtrstoud what I mean by 
 iurlgmcnt, 1 proceeil tii make Bome genenii 
 observalimiH concerning it.
 
 414 
 
 ON THE INTELLECTUAL POWERS. 
 
 [essa y 
 
 VI. 
 
 First, Judgment is an act of the mind, 
 specifically different from simple apprehen- 
 sion, or the bare conception of a thing.* 
 It would be unnecessary to observe this, if 
 some philosophers had not been led by their 
 theories to a contrary opinion. [500] 
 
 Although there can be no judgment with- 
 out a conception of the things about which 
 we judge, yet conception may be without any 
 judgment.-|- Judgment can be expressed 
 by a proposition only, and a proposition is 
 a complete sentence ; but simple apprehen- 
 sion may be expressed by a word or words, 
 which make no complete sentence. When 
 simple apprehension is employed about a 
 proposition, every man knows that it is one 
 thing to apprehend a proposition — that is, 
 to conceive what it means — but it is quite 
 another thing to judge it to be true or false. 
 
 It is self-evident that every judgment 
 must be either true or false ; but simple 
 apprehension, or conception, can neither be 
 true nor false, as was shewn before. 
 
 One judgment may be contradictory to 
 another ; and it is impossible for a man to 
 have two judgments at the same time, which 
 he perceives to be contradictory. But con- 
 tradictory propositicMis may be conceived:}: 
 at the same time without any difficulty. 
 That the sun is greater than the earth, and 
 that the sun is not greater than the earth, 
 are contradictory propositions. He that 
 apprehends the meaning of one, apprehends 
 the meaning of both. But it is impossible 
 for hun to judge both to be true at the same 
 time. He knows that, if the one is true, 
 tile other must be false. For these reasons, 
 I hold it to be certain that judgment and 
 simple apprehension are acts of the mind 
 specifically different. 
 
 Secondly, There are notions or ideas that 
 ought to be referred to the faculty of judg- 
 ment as their source ; because, if we had 
 not that faculty, they could not enter into 
 our minds ; and to those tliat have that 
 faculty, and are capable of reflecting upon 
 its operations, they are obvious and familiar. 
 
 Among these we may reckon the notion 
 of judgment itself ; the notions of a propos- 
 ition — of its subject, predicate, and copula; 
 of affirmation and negation, of true and 
 false ; of knowledge, belief, disbelief, opi- 
 nion, assent, evidence. From no source 
 could we acquire these notions, but from 
 reflecting upon our judgments. Relations 
 of things make one great class of our notions 
 or ideas ; and we cannot have the idea of 
 any relation without some exercise of judg- 
 ment, as will appear afterwards. [501] 
 Thirdli/, In persons come to years of 
 
 * Which, however, implies a judgment .ifErming 
 lt8 subjective reality— an existential judgment.— H. 
 
 t See last note, and above, p. ■.i4;j,a, note *, and n- 
 3-5, a, notef.— H. 
 
 ti-'ee above, p. 377, b, ii,,te.~H 
 
 understanding, judgment necessarily accom- 
 panies all sensation, perception by the 
 senses, consciousness, and memory, but not 
 conception.* 
 
 I restrict this to persons come to the years 
 of understanding, because it may be a ques- 
 tion, whether infants, in the first period of 
 life, have any judgment or belief at all." 
 The same question may be put with regard 
 to brutes and some idiots. This question 
 is foreign to the present subject ; and I say 
 nothing here about it, but speak only of 
 persons who have the exercise of judg- 
 ment. 
 
 In them it is evident that a man who 
 feels pain, judges and believes that he is 
 really pained. The man who perceives an 
 object, believes that it exists, and is what 
 he distinctly perceives it to be ; nor is it in 
 his power to avoid such judgment. And 
 the like may be said of memory, and of 
 consciousness. Whether judgment ought 
 to be called a necessary concomitant of 
 these operations, or rather a part or in- 
 gredient of them, I do not dispute ; but it 
 is certain that all of them are accompanied 
 with a determination that something is 
 true or false, and a consequent belief. If 
 this determination be not judgment, it is 
 an operation that has got no name; for it 
 is not simple apprehension, neither is it 
 reasoning ; it is a mental affirmation or 
 negation ; it may be expressed by a propo- 
 sition affirmative or negative, and it is 
 accompanied with the firmest belief. These 
 are the characteristics of judgment ; and I 
 must call it judgment, till I can find another 
 name to it. 
 
 The judgments we form are either of 
 things necessary, or of things contingent. 
 That three times three is nine, that the 
 wh<ile is greater than a part, are judg- 
 ments about things necessary. [502] Our 
 assent to such necessary propositions is not 
 grounded upon any operaticm of sense, of 
 memory, or of consciousness, nor does it 
 require their concurrence ; it is unaccom- 
 panied by any other operation but that of 
 conception, which must accompany all judg- 
 ment ; we may therefore call this judgment 
 of things necessary pure judgment. Our 
 judgment of things contingent must always 
 rest upon some other operation of the mind, 
 such as sense, or memory, or consciousness, 
 or credit in testimony, which is itself 
 grounded upon sense. 
 
 That I now write upon a table covered 
 with green cloth, is a contingent event, 
 which I judge to be most undoubtedly true. 
 My judgment is grounded upon my percep- 
 tion, and is a necessary concomitant or in- 
 gredient of my perception. That I dined 
 
 * In so far as there can be Consciousness, there 
 muit be Judgment. — H. 
 
 [.500-502]
 
 CHAP. I.] 
 
 OF JUDGMENT IN GENERAL. 
 
 415 
 
 with such a company yesterday, I judge to 
 be true, because I remember it ; and my 
 judgment necessarily goes along with this 
 remembrance, or makes a part of it. 
 
 There are many forms of speech in com- 
 mon language which shew that the senses, 
 memory and consciousness, are considered 
 as judging faculties. We say that a man 
 judges of colours by his eye, of sounds by 
 his ear. We speak of the evidence of sense, 
 the evidence of memory, the evidence of 
 consciousness. Evidence is the ground of 
 judgment; and when we see evidence, it is 
 impossible not to judge. 
 
 When we speak of seeing or remember- 
 ing anything, we, indeed, hardly ever add 
 tliat we judge it to be true. But the rea- 
 son of this appears to be, that such an 
 addition would be mere superfluity of 
 speech, because every one luiows that 
 what I see or remember, I must judge to 
 be true, and cannot do otherwise. 
 
 And, for the same reason, in speaking of 
 anything- that is self-evident or strictly de- 
 monstrated, we do not say that we judge 
 it to be true. This would be superfluity 
 of speech, because every man knows th :t we 
 must judge that to be true which we hold 
 self-evident or demonstrated. [503] 
 
 When you say you saw such a thing, or 
 that you distinctly remember it, or when 
 you say of any proposition that it is self- 
 evident, or strictly demonstrated, it would 
 be ridiculous after this to ask whether you 
 judge it to be true ; nor would it be less 
 ridiculous in you to inform us that you do. 
 It would be a superfluity of speech of the 
 same kind as if, not content with saying 
 that you saw such an object, you should 
 add that you saw it with your eyes. 
 
 There is, therefore, good reason why, in 
 speaking or writing, judgment should not 
 be e.\pressly mentioned, when all men know 
 it to be necessarily implied ; that is, when 
 there can be no doubt. In such cases, we 
 barely mention the evidence. But wlien 
 the evidence mentioned leaves room for 
 doubt, then, without any superfluity or tau- 
 tology, we say wc judge the thing to be so, 
 because tliis is not imj)lied in what was said 
 before. A woman with child never says, 
 that, going such a journey, she carried her 
 child along with Jier. We know that, while 
 it is in her W(jnil), slie must carry it along 
 with lier. There are some operations of 
 mind that may be said to carry judgment 
 in tlieir womb, and can no more leave it 
 behind them than the pregnant woman can 
 leave her child. 'I'lierefore, in spe;iking of 
 sirch operations, it is not exjiressed. 
 
 Perliajm this manner of speaking may 
 have led I'hilosopliers into the opinion that, 
 in perception by the senses, in memory, 
 and in consciousness, there is no judgment 
 at all. Because it is not nientione<l in 
 [5O.S-.0O.5] 
 
 speaking of these faculties, they conclude 
 tliat it does not accompany tliem ; that they 
 are only dift'erent modes of simple appre- 
 hension, or of acquiring ideas ; and that it 
 is no part of their office to judge. [504] 
 
 I apprehend the same cause has led Mr 
 Locke into a notion of judgment which I 
 take to be peculiar to hhn. He thinks th.at 
 the mind has two faculties conversant about 
 truth and falsehood. First, knowledge; 
 and, secondly, judgment. In the first, the 
 perception of the agreement or disagree- 
 ment of the ideas is certain. In the second, 
 it is not certain, but probable only. 
 
 According to this notion of judgment, it 
 is not by judgment that I perceive that two 
 and three make five ; it is by the faculty of 
 knowledge. I apprehend there can be no 
 knowledge without judgment, though there 
 may be judgment without that certainty 
 wliicli we connnonly cull knowledge. 
 
 Sir Locke, in another place of his Essay, 
 tells us, '' That the notice we have by our 
 senses of the existence of things without us, 
 though not altogether so certain as our in- 
 tuitive knowledge, or the deductions of our 
 reason about abstract ideas, yet is an as- 
 surance that deserves the name of know- 
 ledge." I think, by this account of it, and 
 by his definitions before given of knowledge 
 and judgment, it deserves as well the name 
 o{ jnilyment. 
 
 That I may avoid disputes about the 
 meaning of words, I wish the reader to un- 
 derstand, that I give the name of judgment 
 to every determination of the mind con- 
 cerning what is true or what is false. This, 
 I think, is wliat logicians, from the days of 
 Aristotle, have called judgment. Whether 
 it be called one faculty, as I think it has 
 always been, or whether a philosopher 
 chooses to split it into two, seems not very 
 material. And, if it be granted that, by our 
 senses, our memory, and consciousness, we 
 not only have ideas or simple apprehen- 
 sions, but form deterniinations concerning 
 what is true and what is false — whetiier 
 these determinations ought to bo called 
 knowledge or judymeiU, is of small moment. 
 [505] 
 
 The judgments grounded upon the evi- 
 dence of sense, of memory, and of conscious- 
 ness, put all men upon a level. Tlie plii- 
 losoplier, with regard to these, has no pre- 
 rogative above the illiterate, or even above 
 the savage. 
 
 Their reliance upon the testimony of 
 these fa<:(dties is as firm and as well 
 grounded as his. liis Kuperiority is in 
 judgments of anotlier kind — in judgments 
 about things abstract and necessary. And 
 lie is unwiiliiig to give the name of judg- 
 ment to that wherein tiie most ignorant 
 and unimproved of the upecics are his 
 ('(juals.
 
 41tf 
 
 ON THE INTELLECTUAL POWERS. 
 
 [essay 
 
 v'l. 
 
 But philosophers have never been able 
 to give any definition of judgment which 
 does not apply to the determinations of 
 our senses, our memory, and conscious- 
 ness, nor any definition of simple appre- 
 hension which can comprehend those deter- 
 minations. 
 
 Our judgments of this kind are purely 
 the gift of Nature, nor do they admit of 
 improvement by culture. The memory of 
 one man may be more tenacious than that 
 of another ; but both rely with equal assur- 
 ance upon what they distinctly remember. 
 One man's sight may be more acute, or his 
 feeling more delicate, than that of another; 
 but both give equal credit to the distinct 
 testimony of their sight and touch. 
 
 And, as we have this belief by the con- 
 stitution of our nature, without any effort 
 of our own, so no effort of ours cau over- 
 turn it. 
 
 The sceptic may perhaps persuade him- 
 self, in general, that he has no • ground to 
 believe his senses or his memory : but, in 
 particular cases that are interesting, his 
 disbelief vanishes, and he finds himself 
 under a necessity of believing both. [506^ 
 
 These judgments may, in the strictest 
 sense, be called judgments of nature. Na- 
 ture has subjected us to them, whether we 
 will or not. They are neither got, nor can 
 they be lost by any use or abuse of our 
 faculties ; and it is evidently necessary for 
 our preservation that it should be so. For, 
 if belief in our senses and in our memory 
 were to be learned by culture, the race of 
 men would perish before they learned this 
 lesson. It is necessary to all men for their 
 being and preservation, and therefore is 
 unconditionally given to all men by the 
 Author of Nature. 
 
 I acknowledge that, if we were to rest 
 in those judgments of Nature of which we 
 now speak, without building others upon 
 them, they would not entitle us to the deno- 
 mination of reasonable beings. But yet 
 they ought not to be despised, for they are 
 the foundation upon which the grand super- 
 structure of human knowledge must be 
 raised. And, as in other superstructures 
 the foundation is commonly overlooked, so 
 it has been in this. The more sublime 
 attainments of the human mind have at- 
 tracted the attention of philosophers, while 
 they have bestowed but a careless glance 
 upon the humble foundation on which the 
 whole fabric rests. 
 
 A fourtli observation is, that some exer- 
 cise of judgment is necessary in the forma- 
 tion of ail abstract and general conceptions, 
 whether more simple or more comj)lex ; in 
 dividing, in defining, and, in general, in 
 forming all Hear and distinct conceptions 
 of things, which are the only fit materials 
 of reasoning. 
 
 These operations are allied to each otlier, 
 and therefore I bring them under one ob- 
 servation. They are more allied to cur 
 rational nature than those mentioned in the 
 last observation, and therefore are consi- 
 dered by themselves. 
 
 That I may not be mistaken, it may be 
 observed that I do not say that abstract 
 notions, or other accurate notions of things, 
 after they have been formed, cannot be 
 barely conceived without any exercise of 
 judgment about them. I doubt not that 
 they may : but what I say is, that, in their 
 formation in the mind at first, there must 
 be some exercise of judgment. [^^7] 
 
 It is impossible to distinguish the diflerent 
 attributes belonging to the same subject, 
 without judging that they are really different 
 and distinguishable, and that they have that 
 relation to the subject which logicians ex- 
 press, by saying that they may be predicated 
 of it. We cannot generalise, without judg- 
 ing that the same attribute does or may be- 
 long to many individuals. It has been 
 shewn that our simplest general notions 
 are formed by these two operations of dis- 
 tinguishing and generalising ; judgment 
 therefore is exercised in forming the simplest 
 general notions. 
 
 In those that are more complex, and 
 which have been shewn to be formed by 
 combining the more simple, there is another 
 act of the judgment required ; for such 
 combinations are not made at random, but 
 for an end; and judgment is employed in 
 fitting them to that end. We form complex 
 general notions for conveniency of arrang- 
 ing our thoughts in discourse and reasoning ; 
 and, therefore, of an infinite number of com- 
 binations that might be formed, we choose 
 only those that are useful and necessary. 
 
 That judgment must be employed in 
 dividing as well as in distinguishing, ap- 
 pears evident. It is one thing to divide a 
 subject properly, another to cut it in pieces. 
 Hocnon est divktere, sed frangcre rem, said 
 Cicero, when he censured an improper 
 division of Epicurus. Reason has discovered 
 rules of division, which have been known 
 to logicians more than two thousand years. 
 
 There are rules likewise of defiaition of 
 no less antiquity and authority. A man 
 ma} no doubt divide or define properly with- 
 out attending to the rules, or even without 
 knowing them. But this can only be when 
 he has judgment to perceive that to be right 
 in a particular case, which the rule de- 
 teniiines to be right in all cases. 
 
 I add in general, that, without some de- 
 gree of judgment, we can form no accurate 
 and distinct lioiions of things ; so that one 
 province of judgment is, to aid us in form- 
 ing clear and distinct conceptions of things, 
 whicli are the only fit materials for reason- 
 ing. [508] 
 
 [^506-508]
 
 CHAP. 
 
 I-] 
 
 OF JUDGMENT IN GENERAL. 
 
 417 
 
 This will probably appear to be a paradox 
 to philosophers, who have always considered 
 the formation of ideas of every kind as be- 
 longing to simple apprehension ; and that 
 the sole province of judgment is to put them 
 together in affirmative or negative proposi- 
 tions ; and therefore it requires some con- 
 firmation. 
 
 Fir.\t, I think it necessarily follows, from 
 what has been already said in this observa- 
 tion. For if, without some degree of judg- 
 ment, a man can neither distinguish, nor 
 divide, nor define, nor form any general 
 notion, simple or complex, he surely, with- 
 out some degree of judgment, cannot have 
 in his mind the materials necessary to 
 reasoning. 
 
 There cannot be any proposition in lan- 
 guage which d )es not involve some general 
 conception. 'J he proposition, that I exist, 
 which Des Cartes thought the first of all 
 truths, and the foundation of all knowledge, 
 cannot be conceived without the conception 
 of existence, one of the most abstract general 
 conceptions A man cannot believe his own 
 existence, or the existence of anything ho 
 sees (ir remembers, until he has so much 
 judgment as to distinguish things that really 
 exist from things which are only conceived. 
 He sees a man six feet high ; he conceives 
 a man sixty feet high : he judges the first 
 object to exist, because he sees it ; the 
 second he does not judge to exist, because 
 he only conceives it. Now, I would ask, 
 Whether he can attribute existe^ice to the 
 first object, and not to the second, without 
 knowing what existence means ? It is im- 
 possible. 
 
 How early the notion of existence enters 
 into the mind, I cannot determine ; but it 
 must certainly be in the mind as soon as 
 we can affirm of anything, with understand- 
 ing, that it exists. [509] 
 
 In every other proposition, the predicate, 
 at least, must be a general notion — a pre- 
 dicable and an universal being one and the 
 same. Besides this, every proposition either 
 affirms or denies. And no man can iiave 
 a distinct conception of a proposition, who 
 does not understand distinctly the meaning 
 of affi' ming or denying. But these are very 
 general conceptioiis, and, as was before 
 observe 1, are derived from judgment, as 
 their source and origin. 
 
 I am sensible tiiat a strong objection may 
 be made to this reasoning, and that it may 
 seem to lead to an absurdity or a contra- 
 diction. It may be said, that every judg- 
 ment is a mental affirmation or negation. 
 If, therefore, some previous exercise of 
 judgment be necessary to understand what 
 is meant by affirmation or negation, the 
 exerciae of judgment must go before any 
 judgment which \b absurd. 
 
 In like manner, every judgment may be 
 [509,510] 
 
 expressed by a proposition, and a proposi. 
 tiou must be co,:ceived before we can jud'^e 
 of it. If, therefore, we cannot conceive the 
 meaning of a proposition without a previous 
 exercise of judgment, it follows that judg- 
 ment must be previous to the conception of 
 any proposition, and at the same time that 
 the conception of a proposition must be pre- 
 vious to all judgment, which is a contra- 
 diction. 
 
 The reader may please to observe, that 
 I have limited what I have said to distinct 
 conception, and some degree of judgment; 
 and it is by this means I hope to avoid this 
 labyrinth of absurdity and contradiction. 
 The faculties of conception and judgment 
 have an infancy and a maturity as man has. 
 What I have said is limited to their mature 
 state. I believe in their infant state they 
 are very weak and indistinct ; and that, by 
 imperceptible degrees, they grow to ma- 
 turity, each giving aid to the other, and 
 receiving aid from it. But which of them 
 first began this friendly intercourse, is be- 
 yond my ability to determine. It is like 
 the question concerning the bird and the 
 egg- [5 10 J 
 
 In the present state of things, it is true 
 that every bird comes from an egg, and 
 every egg from a bird ; and each may be 
 said to be previous to the other. But, if 
 we go back to the origin of things, there 
 must have been some bird that did not 
 come from any egg, or some egg that did 
 not come from any bird. 
 
 In like manner, in the mature state of 
 man, distinct concei)tion of a proposition 
 supposes some previous exercise of judg- 
 ment, and distinct judgment supposes dis- 
 tinct conception. Kach may truly be said 
 10 come from the other, as the bird from 
 ;he egg, and the egg from the bird. But, 
 if we trace back this succession to its origin 
 — that is, to the first proposition that was 
 ever conceived by the man, and the first 
 judgment he ever formed— I determine no- 
 thing about them, nor do I know in what 
 order, or how, they were produced, any 
 more than how the bones grow in the 
 womb of her that is with child. 
 
 The first exercise of these faculties of 
 conception and judgment is hid, like tlio 
 sources of the Nile, in an unknown region. 
 The necessity of some degree of judg- 
 ment to clear and distinct conceptiona of 
 things, may, I think, be illustrated by this 
 similitude. 
 
 An artist, siipjjnse a carpenter, cannot 
 work in his art without tools, and tin bo 
 tools must bo made by art. The cxerriso 
 of the art, therefore, is necessary to niaku 
 the tools, and the tools are necesBary to the 
 exercise of the art. There is the winin 
 appearance of contradiction, tm in what I 
 have advanced concerning the nec«B«ity of 
 
 2 H
 
 416 
 
 ON THK INTELLECTUAL POWERS. 
 
 [essay 
 
 VI. 
 
 ,some degree of judgment, in order to form 
 .clear and distinct conceptions of things. 
 .These are the tools we must use in judging 
 ^nd in reasoning, and without them must 
 make very bungling work ; jot the«e tools 
 cannot be made without some exercise of 
 judgment [511] 
 
 The necessity of some degree of judg- 
 ment in forming accurate and distinct no- 
 tions of things will farther appear, if we 
 consider attentively what notions we can 
 form, without any aid of judgment, of the 
 objects of sense, of the operations of our 
 own minds, or of the relations of things. 
 
 To begin with the objects of sense. It 
 is acknowledged, on all hands, that the first 
 notions we have of sensible objects are got 
 .by the external senses only, and probably 
 before judgment is brought forth ; but these 
 first notions are neither simple, nor are 
 they accurate and distinct : they are gross 
 and indistinct, and, like the chaos, a rudis 
 indigealnque moles. Before we can have 
 .any distinct notion of this mass, it must be 
 analysed ; the heterogeneous parts must be 
 separated in our conception, and the simple 
 elements, which before lay hid in the com- 
 mon mass, must first be distinguished, and 
 then put together into one whole. 
 
 In this way it is that we form distinct 
 notions even of the objects of sense ; but 
 this process of analysis and composition, by 
 habit, becomes so ea.sy, and is performed 
 so readily, that we are apt to overlook it, 
 and to impute the distinct notion we have 
 formed of the object to the senses alone ; 
 and this we are the more prone to do 
 because, when once we have distinguished 
 the sensible qualities of the object from 
 one another, the sense gives testimony to 
 each of them. 
 
 You perceive, for instance, an object 
 white, round, and a foot in diameter. I 
 grant that you perceive all these attributes 
 of the object by sense ; but, if you had not 
 .been able to distinguish the colour from 
 the figure, aid both from the magnitude, 
 your senses would only have given you one 
 complex and confused notion of all these 
 mingled together. 
 
 A man who is able to say with under- 
 standing, or to determine in his own mind, 
 that this object is white, must have distin- 
 guished whiteness from other attributes. 
 If he h.as not made this distinction, he does 
 not understand what he says. [512] 
 
 Suppose a cube of brass to be presented 
 at the same time to a child of a year old 
 and to a man. The regularity of the figure 
 will attract the attention of both. Both 
 have the senses of sight and of touch in 
 equal perfection ; and, therefore, if any- 
 thing be discovered in this object by the 
 man, which cannot be discovered by the 
 child, it must be owing, not to the senses, 
 
 but to some other faculty which the child 
 has not yet attained. 
 
 First, then, the man can easily distin- 
 guish the body from the surface which 
 terminates it ; this the child cannot do. 
 Secondly, The man can perceive that this 
 surface is made up of six planes of the same 
 figure and magnitude ; the child cannot 
 discover thi.'i. Thirdly, The man perceives 
 that each of these planes has four equal 
 sides and four equal angles ; and that the 
 opposite sides of each plane and the oppo- 
 site planes are parallel. 
 
 It will surely be allowed, that a man of 
 ordinary judgment may observe all this in 
 a cube which he makes an object of con- 
 templation, and takes time to consider ; 
 that he may give the name of a square to 
 a plane terminated by four equal sides and 
 four equal angles ; and the name of a cube 
 to a solid terminated by six equal squares •. 
 all this is nothing else but analysing the 
 figure of the object presented to his senses 
 into its simplest elements, and again com- 
 pounding it of those elements. 
 
 By this analysis and composition two 
 effects are produced. First, From the one 
 complex object which his senses presented, 
 though one of the most simple the senses 
 can present, he educes many simple and 
 distinct notions of right lines, angles, plain 
 surface, solid, equality, parallelism ; notions 
 which the child has not yet faculties to 
 attain. Secondly, When he considers the 
 cube as compounded of these element.s, put 
 together in a certain order, he has then, 
 and not before, a distinct and scientific 
 notion of a cube. The child neither con- 
 ceives those elements, nor in what order 
 they must be put together in order to make 
 a cube ; and, therefore, has no accurate 
 notion of a cube which can make it a sub- 
 ject of reasoning. [513] 
 
 Whence I think we may conclude, that 
 the notion which we have from the senses 
 alone, even of the simplest objects of sense, 
 is indistinct and incapable of being either 
 described or reasoned upon, until it is ana- 
 ly.sed into its simple elements, and con- 
 sidered as compounded of those elements. 
 
 If we should apply this reasoning to more 
 complex objects of sense, the conclusion 
 would be still more evident. A dog may be 
 taught to turn a jack, but he can never be 
 taught to have a distinct notion of a jack. 
 He sees every part as well as a man ; but 
 the relation of the parts to one another 
 and to the whole, he has not judgment to 
 comprehend. 
 
 A distinct notion of an object, even of 
 sense, is never got in an instant ; but the 
 sense performs its office in an instant. Time 
 is not required to see it better, but to analyse 
 it, to distinguish the different parts, and their 
 relation to one another and to the whole. 
 
 [511-513]
 
 t'HAl'. 
 
 »•] 
 
 OF JUDGMENT IN GENERAL. 
 
 4 It) 
 
 Hence it is that, wheu any vehement 
 passion or emotion liuiders the cool applica- 
 tion of judgment, we get no distinct notion 
 of an object, even though the sense be long 
 directed to it. A man who is put into a 
 panic, by thinking he sees a ghost, may 
 stare at it long without having any distinct 
 notion of it ; it is his understanding, and 
 not his sense, that is disturbed by his horror. 
 If he can lay that aside, judgment immedi- 
 ately enters upon its otiice, and examines 
 the length and breadth, the colour, and 
 figure, and distance of the object. Ot these, 
 while his panic lasted, he had no distinct 
 notion, though his eyes were open all the 
 time. 
 
 When the eye of sense is open, but that 
 of judgment shut by a panic, or any violent 
 emotion that engrosses the mind, we see 
 things confusedly, and probably nmch in the 
 same manner that brutes and perfect idiots 
 do, and infants before the use of judgment. 
 [514] 
 
 There are, therefore, notions of the objects 
 of sense which are gross and indistinct, and 
 there are others that are distinct and scienti- 
 fic. The former may be got from the senses 
 alone, but the latter cannot be obtained with- 
 out some degree of judgment. 
 
 The clear and accurate notions which 
 geometry pi-escnts to us of a point, a right 
 line, an angle, a square, a circle, of ratios 
 direct and inverse, and others of that kind, 
 can find no admittance into a mind that has 
 not some degree of judgment. They are 
 not properly ideas of the senses, nor are 
 they got by compoundinji; ideas of the 
 senses, but by analysing the ideas or no- 
 tions we get by the senses into their simplest 
 elements, and again combining these ele- 
 ments into various accurate and elegant 
 forms, which the senses never did nor can 
 exhibit. 
 
 Had Mr Hume attended duly to this, it 
 ought to have prevented a very bold attemjit, 
 which he has prosecuted through fourteen 
 pages of his " Treatise of Human Nature,'' 
 to prove that geometry is founded upon ideas 
 that are not exact, and axioms that are not 
 precisely true. 
 
 A mathematician miglit be tempted to 
 think that the man who seriously under- 
 takes this has no great acquaintance with 
 geometry ; but I apprehend it is to be im- 
 puted to another cause, to a zeal for his own 
 system. \Vc see that even men of genius 
 may be drawn into strange paradoxes, by 
 an attachment to a favourite idol of the 
 understanding, when it demands so costly a 
 sacrifice. 
 
 We Protestants think that the devotees 
 of the Roman Church pay no small tribute 
 to her authority when they nMionnce tlieir 
 five senses in oljcdience to jier decrees. Mr 
 Iliniie's devotion to his system carries liini 
 I r, 1 t-.-i in! 
 
 even to trample upon mathematical demon- 
 stration. [•'>lj] 
 
 Tlie fundamental articles of his system 
 are, that all the perceptions of the human 
 mind are either im])ressions or ideas, a)id 
 that ideas are only faint copies of impres- 
 sions. The idea of a right line, therefore, is 
 only a faint copy of some line that has been 
 seen, or felt by touch ; and the faint copy 
 cannot be more perfect than the original. 
 Now of such right lines, it is evident that 
 the axioms of geometry arc not precisely 
 true ; for two lines that are straight to our 
 sight or touch may include a space, or they 
 may meet in more points than one. If, 
 therefore, we cannot form any notion of a 
 straight line more accurate than that which 
 we have from the senses of sight and touch, 
 geometry has no solid foundation. If, on 
 the other hand, the geometrical axioms are 
 ]n-ecisely true, the idea of a right line is not 
 copied from any impression of sight or touch, 
 but must have a different origin and a more 
 perfect standard. 
 
 As the geometrician, by reflecting only 
 upon the extension and figure of matter, 
 forms a set of notions more accurate and 
 scientific than any which the senses exhi- 
 bit, so the natural philosopher, reflecting 
 upon other attributes of matter, forms 
 another set, such as those of density, quan- 
 tity of matter, velocity, momentum, fluidity, 
 elasticity, centres of gravity, and of oscilla- 
 tion. These notions are accurate and 
 scientific ; but they cannot enter into a 
 mind that has not some degree of judg- 
 ment, nor can we make them intelligible to 
 children, until they have some ripeness of 
 understanding. 
 
 In navigation, the notions of latitude, 
 longitude, course, leeway, cannot be made 
 intelligible to children ; and so it is with 
 regard to the terms of every science, and 
 of every art about which we can reason. 
 They have had their five senses as perfect 
 as men for years before they are capable 
 of distinguishing, comparing, and perceiv- 
 ing the relations of things, so as to be able 
 to form such notions. They acquire the 
 intellectual powers by a slow progress, and 
 by imperceptible degrees ; and by means 
 of them, learn to form distinct and accurate 
 notions of things, which the senses could 
 never have imparted. [510] 
 
 Having said so nmch of the notions we 
 get from the senses alone of the olijecta of 
 sense, let us next consider what notions we 
 can have from consciousness alone of the 
 operations of our minds. 
 
 Mr Locke very i)roperly calls conscious- 
 ness an internal sense. It gives the like 
 innnediateknowledgeoflhingsin tiie mind — 
 that is, of ourftwn thoughts and feelings — 
 as the senses give us of things external. 
 'I'iiere is this dilleren'*-, however, that an 
 
 '2 K 'J
 
 420 
 
 ON THE INTELLECTUAL POWERS. 
 
 [eSSAV VI. 
 
 external object may be at rest, and the 
 sense may be employed about it for some 
 time. But the objects of consciousness 
 are never at rest : the stream of thought 
 flows like a river, without stopping a mo- 
 ment ; the whole train of thought passes in 
 succession under the eye of consciousness, 
 which is always employed about the present. 
 But is it consciousness that analyses com- 
 plex operations, distinguishes their different 
 ingredients, and combines them in distinct 
 parcels under general names ? This surely 
 is not the work of consciousness, nor can it 
 be performed without reflection,* recollect- 
 ing and judging of what we were conscious 
 of, and distinctly remember. This reflec- 
 tion does not appear in children. Of all 
 the powers of tlie mind, it seems to be of 
 the latest growth, whereas consciousness is 
 coeval with the earliest. "f 
 
 Consciousness, being a kind of internal 
 sense, can no more give us distinct and 
 accurate notions of the operations of our 
 minds, than the external senses can give 
 of external objects. Reflection upon the 
 operations of our minds is the same kind of 
 operation with that by which we form dis- 
 tinct notions of external objects. They 
 differ not in their nature, but in this only, 
 that one is employed about external, and 
 the other about internal objects ; and both 
 may, with equal propriety, be called reflec- 
 tion. [517] 
 
 Mr Locke has restricted the word reflec- 
 
 -* See above, p. 2^2, a, note *.— H. 
 
 t See above, p. 239, b Asa corollary of this truth, 
 
 Mr Stewart makes the following observations, in 
 which he is supported by every competent authority 
 in education. The two northern universities have 
 long witlidrawn themselves from the reproach of 
 placing Physics last in their curriculum of arts. In 
 that of Edinbureh, no order is prescribi d ; but in St 
 Andrew's and Glasgow, the class of Physics still stands 
 after those of Mental Philosophy. 'J his absurdity is, 
 it is to be observed, altogether of a modern intro- 
 duction For, when our Scotti'^h universities were 
 lounded, and long alter, the pliilosophv of mind was 
 taught by the h'rofessor of Physics. " I apprehend," 
 says Mr Stewart, "that the study of the mind should 
 form the last branch of the education of youth ; an 
 order wh'Ch nature herself seems to point out, by 
 what I have already remarked v/itli respect to the 
 developcment of our faculties. Alter the under, 
 standing is well stored with [larticular fdcis, and 
 has been conversant with particular scientific pur. 
 suits, it will be enabled to speculate concerning its 
 own powers with additional arivartage, and will run 
 no hazard in intlulging too far in such inquiries. 
 Nothing can be mure absurd, on this as well as on 
 many other accounts, than the common practice 
 which is followed in our universities, [in some only,] 
 of beginning a course of philosophical education with 
 the study of Logic. If thisorder were completely re- 
 versed ; and if the s'.udy of Logic were delayed till 
 after the mind of 'he student was well stored with 
 particular facts in Physics, in Chemistry, in Natural 
 and Civil History, his atiention might be led with 
 the most important advantage, and without any dan. 
 ger to his pon er of observation, to an examination 
 of his own faculties, which, besides opening to him 
 a new and pleasing field of speculation, would enable 
 him to form an estimate of his own powers, of the 
 acquisitions he has made, of the habits he has formed, 
 and of the farther improvements of which his mind 
 is susceptible."— H. 
 
 tion to that which is employed about the 
 operations of our minds, without any 
 authority, as I think, from custom, the 
 arbiter of language. For, surely, I may 
 reflect upon what I have seen or heard, as 
 well as upon what I have thought.* The 
 word, in its proper and common meaning, 
 is eqtially applicable to objects of sense, 
 and to objects of consciousness. -f* He has 
 likewise confounded reflection with con- 
 sciousness, and seems not to have been 
 aware that they are different powers, and 
 appear at very different periods of life X 
 
 If that eminent philosopher had been 
 aware of these mistakes about the meaning 
 of the word reflection, he would, I think, 
 have seen that, as it is by reflection upon 
 the operations of our own minds that we 
 can form any distinct and accurate notions 
 of them, and not by consciousncbs without 
 reflection, so it is by reflection upon the 
 objects of sense, and not by the senses 
 without reflection, that we can form dis- 
 tinct notions of them. Reflection upon any- 
 thing, whether external or internal, makes 
 it an object of our intellectual powers, by 
 which we survey it on all sides, and form 
 such judgments about it as appear to be 
 just and true. 
 
 I proposed, in the third place, to consi- 
 der our notions of the relations of things : 
 and here I think, that, without judg- 
 ment, we cannot have any notion of rela- 
 tions. 
 
 There are two ways in which we get the 
 notion of relations. The first is, by com- 
 paring the related objects, when we have 
 before had the conception of both. By this 
 comparison, we perceive the relation, either 
 immediately, or by a process of reasoning. 
 That my foot is longer than my finger, 1 
 perceive immediately ; and that three is 
 the half of six. This immediate perception 
 is immediate and intuitive judgment. That 
 the angles at the base of an isosceles triangle 
 are equal, I perceive by a process of reason- 
 ing, in which it will be acknowledged there 
 is judgment. 
 
 Another way in which we get the notion 
 of relations (which seems not to have occur- 
 red to Mr Locke) is, when, by attention to 
 one of the related objects, we perceive or 
 judge that it must, from its nature, have a 
 certain relation to something else, which 
 before, perhaps, we never thought of; and 
 thus our attention to one of the related ob- 
 
 * See note before last, and note at p. 347, b. — H. 
 
 t Mr Stewart makes a curious mistatement of the 
 moaning attached by Reid to the word Reflection, if 
 this passage and others are taken into accounl.^See 
 Ekments, I. p. lOii, note t-— H. 
 
 X Consciousness and lipflection cannot be analysed 
 into difTerent powers. Reflection is only, in Locke's 
 meaning of the word, (and this is the more correct,) | 
 Consciousness, concentrated by an act of Will on the • 
 lihjenomena of mind — ?'. e., internal Attention ; in i 
 Reid's, what is it but Attention in general ?— H. ; 
 
 [517] '
 
 CHAP. 
 
 u.] 
 
 OF COMMON SP:\SE. 
 
 4-21 
 
 jects produces the notion of a correlate, and 
 of a certain relation between them. [518] 
 
 Thus, when I attend to colour, figure, 
 weight, I cannot help judging these to be 
 qualities which cannot exist without a sub- 
 ject ; tliat is, something which is coloured, 
 figured, heavy. If I had not perceived such 
 things to be qualities, I should never have 
 had any notion of their subject, or of their 
 relation to it. 
 
 By attending to the operations of think- 
 ing, memory, reasoning, we perceive or 
 judge that there must be something which 
 thinks, remembers, and reasons, which we 
 call the mind. When we attend to any 
 change tliat happens in Nature, judgment 
 informs us that there must be a cause of 
 this change, which had power to produce 
 it ; and thus we get the notions of cause 
 and effect, and of the relation between 
 them. ^V aeu we attend to body, we per- 
 ceive that it cannot exist without space ; 
 hence we get the notion of space, (which is 
 neither an object of sense nor of conscious- 
 ness,) and of the relation which bodies 
 have to a certain portion of unlimited space, 
 as their place. 
 
 I apprehend, therefore, that all our no- 
 tions of relations may more properly be 
 ascribed to judgment as their source and 
 origin, than to any other power of the 
 mind. We must first perceive relations 
 by our judgment, before we can conceive 
 them without judghig of them ; as we must 
 first perceive colours by sight, before we 
 can conceive them without seeing them. I 
 think Mr Locke, when he comes to speak 
 of the ideas of relations, does not say that 
 they are ideas of sensation or reflection, 
 but only that they terminate in, and are 
 concerned about, ideas of sensation or re- 
 flection. [519] 
 
 The notions of unity and number are so 
 abstract, that it is impossible they should 
 enter into the mind until it has some degree 
 of judgment. We see with what difficulty, 
 and how slowly, children learn to use, with 
 understanding, the names even of small 
 numbers, and how they exult in this acqui- 
 sition when they have attained it. Every 
 number is conceived by the relation which 
 it bears to unity, or to known combinations 
 of units ; and upon that account, as well 
 as on account of its abstract nature, all 
 distinct notions of it require some degree 
 of judgment- 
 
 In its proper place, I shall have occasion 
 to shew tiiut judgment is an ingredient in 
 all determinations of taste, in ail moral 
 determinations, and in many of our jias- 
 sions and affections. So that this openi- 
 tion, after we come to have any exercise of 
 judgment, mixes with most of the operations 
 (if our minds, and, in analysing them, cannot 
 i)e overlooked without confusion and error. 
 (^.518-.520] 
 
 CHAPTER II. 
 
 OF COMMON SENSE. 
 
 The word sense, in common language, 
 seems to have a different meaning from that 
 which it has in the writings of philosophers ; 
 and those different meanings are apt to bo 
 confounded, and to occasion embarrassment 
 and error. 
 
 Not to go back to ancient philosophy upon 
 this point, modern philosophers consider 
 sense as a power that has nothing to do with 
 judgment. Sense they consider as the power 
 by which we receive certain ideas or im- 
 pressions from objects ; and judgment as 
 tile power by which we compare those 
 ideas, and perceive their necessary agree- 
 ments and disagreements. [520] 
 
 The external senses give us the idea of 
 colour, figure, sound, and other qualities of 
 body, primary or secondary. Mr Locke 
 gave the name of an internal sense to con- 
 sciousness, because by it we have the ideas 
 of thought, memory, reasoning, and other 
 operations of our own minds. Dr Hutche- 
 son of Glasgow, conceiving that we have 
 simple and original ideas which cannot be 
 unputed either to the external senses or to 
 consciousness, introduced other internal 
 senses ; such as the sense of harmony, the 
 sense of beauty, and the moral sense. 
 Ancient philosopliers also spake of mternal 
 senses, of which memory was accounted one. 
 
 But all those senses, whether external or 
 internal, have been represented by philo- 
 sophers as the means of furnishing our 
 minds with ideas, without including any 
 kind of judgment. Dr Hutcheson defines 
 a sense to be a determination of the mind 
 to receive any idea from the presence of an 
 object independent on our will. 
 
 " By this term (sense) philosophers, in 
 general, have denominated those faculties 
 in consequence of which we are liable to 
 feelings relative to ourselves only, and from 
 which they have not pretended to draw any 
 conclusions concerning the nature ofthiiigs ; 
 whereas trutii is not relative, but absolute 
 
 and real (Dr Priestlv's " Examination of 
 
 Dr Rcid," &c., p. 12:j".) 
 
 On the contrary, in common language, 
 sense always implies judgment. A mini of 
 sense is a man of judgment. Good sense 
 is good judgment. Nonsense is what is 
 evidently contrary to right judgment. Com- 
 mon sense is tlnit degree of judgment which 
 is common to men with whom we can con- 
 verse and traiisai't business. 
 
 Seeing and hearing, Ijy philosophers, arc 
 called senses, because wo liavc ideiw by 
 
 * On Common Stme, name niul thing, icc Note A. 
 — II.
 
 422 
 
 ON THE INTELLECTUAL POWERS. 
 
 [^HSSAV VI. 
 
 thein ; by the vulgar tliey are called senses, 
 because we judge by them. We judge of 
 colours by the eye ; of sounds by the ear ; 
 of beauty and deformity by taste ; of right 
 and wrong in conduct, by our moral sense 
 or conscience. [521] 
 
 Sometimes philosophers, who represent 
 it as the sole province of sense to furnish 
 us with ideas, fall unawares into the popu- 
 lar opinion that they are judging faculties. 
 Thus Locke, Book IV. chap. 2 :— " And of 
 this, (that the quality or accident of colour 
 doth really exist, and hath a being without 
 me,) the greatest assurance I can possibly 
 have, and to which my faculties can attain, 
 is the testimony of my eyes, which are the 
 proper and sole judges of this thing." 
 
 This popular meaning of the word sense 
 is not peculiar to the English language. 
 The corresponding words in Greek, Latin, 
 and, I believe, in all the European languages, 
 have the same latitude. The Latin words 
 sentire, sententla, sensa,* sensus, from the 
 last of which the English word sense is 
 borrowed, express judgment or opinion, and 
 are applied indifi'erently to objects of exter- 
 nal sense, of taste, of morals, and of the 
 understanding. 
 
 I cannot pretend to assign the reason why 
 a word, which is no term of art, which is 
 familiar in common conversation, should 
 have so different a meaning in philosophical 
 writings. I shall only observe, that the 
 philosophical meaning corresponds perfectly 
 with the account which Mr Locke and other 
 modern philosophers give of judgment. For, 
 if the sole province of the senses, external 
 and internal, be to furnish the mind with 
 the ideas about which we judge and reason, 
 it seems to be a natural consequence, that 
 the sole province of judgment should be to 
 compare those ideas, and to perceive their 
 necessary relations. 
 
 These two opinions seem to be so con- 
 nected, that one may have been the cause 
 of the other. I apprehend, however, that, 
 if both be true, there is no room left for any 
 knowledge or judgment, either of the real 
 existence of contingent things, or of their 
 contingent relations. 
 
 To return to the popular meaning of the 
 word sense. I believe it would be much 
 more difficult to find good authors who never 
 use it in that meaning, than to find such 
 as do. [522] 
 
 We may take Mr Pope as good authority 
 for the meaning of an English word. He 
 uses it often, and, in his " Epistle to the 
 Earl of Burlington," ha3 made a little de- 
 scant upon it. 
 
 * What floes smsa mean? Is it an erratum, or 
 does he refer to sensa, once only, I believe, employed 
 by Cicero, and interpreted by Nonius Marcellus, as 
 " qux seiitiuntur V" — H. 
 
 " Oft have you hinted to your broiher Peer, 
 A certaui truth, which many liuy too dear: 
 Something there is more needful than expense, 
 And something previous ev'ti to laste— 'tis sense. 
 Good sense, winch only is the gift.of heaven. 
 And, though no science, fairly worth the seven ; 
 A light which in yourself you must perceive, 
 Jones and Le Notre have it not to give." 
 
 This inward light or sense is given by 
 heaven to different persons in different de- 
 grees. There is a certain degree of it which 
 is necessary to our being subjects of law and 
 government, capable of managing our own 
 affairs, and answerable for our conduct 
 towards others : this is called common 
 sense, because it is common to all men with 
 whom we can transact business, or call to 
 account for their conduct. 
 
 The laws of all civilised nations distin- 
 guish those who have this gift of heaven, 
 from those who have it not. The last may 
 have rights which ought not to be violated, 
 but, having no understanding in themselves 
 to direct their actions, the laws appoint them 
 to be guided by the understanding of others. 
 It is easily discerned by its effects in men's 
 actions, in their speeches, and even in their 
 looks ; and when it is made a question 
 whether a man has this natural gift or not, 
 a judge or a jury, upon a short conversation 
 with him, can, for the most part, determine 
 the question with great assurance. 
 
 The same degree of understanding which 
 makes a man capable of acting with com- 
 mon prudence in the conduct of life, makes 
 him capable of discovering what is true and 
 what is false in matters that are self-evident, 
 and which he distinctly apprehends. [523] 
 All knowledge, and all science, must be 
 built upon principles that are self-evident ; 
 and of such principles every man who has 
 common sense is a competent judge, when 
 he conceives them distinctly. Hence it is, 
 that disputes very often terminate in an 
 appeal to common sense. 
 
 While the parties agree in the first prin- 
 ciples on which their arguments are ground- 
 ed, there is room for reasoning ; but when 
 one denies what to the other appears too 
 evident to need or to admit of proof, rea- 
 soning seems to be at an end ; an appeal is 
 made to common sense, and each party is 
 left to enjoy his own opinion. 
 
 There seems to be no remedy for this, 
 nor any way left to discuss such appeals, 
 unless the decisions of common sense can 
 be brought into a code in which all reason- 
 able men shall acquiesce. This, indeed, if 
 it be possible, would be very desirable, and 
 would supply a desideratum in logic ; and 
 why should it be thought impossible that 
 reasonable men should agree in things that 
 are self-evident ? 
 
 All that is intended in this chapter is to 
 explain the meaning of common sense, that 
 it may not be treated, as it has been by 
 some, as a new principle, or as a word with- 
 
 [52 1 -.523]
 
 CHAP. II. J 
 
 OF COMMON SENSE. 
 
 423 
 
 out any meaning. I have endeavoured to 
 shew that sense, in its most common, and 
 therefore its most proper meaning, signifies 
 judgment, though pliilosophers often use it 
 in anotlier meaning. From this it is natural 
 I to tiiinlv that common sense should mean 
 I common judgment; and so it really docs. 
 
 What the precise limits are which divide 
 conmion judgment from what is beyond it 
 on the one hand, and from what falls short 
 of it on the other, may be difficult to de- 
 termine ; and men may agree in the mean- 
 ing of the word who have different opinions 
 about those limits, or who even never 
 thought of fixing them. This is as intel- 
 ligible as, that all Englishmen should mean 
 the same thing by the county of York, 
 though perhaps not a hundredth part of 
 them can point out its precise limits. [524] 
 
 Indeed, it seems to me, that common 
 sense is as unaml>iguous a word and as well 
 understood as the county of York. We 
 find it in innumerable places in good writers ; 
 we hear it on innumerable occasions in con- 
 versation ; and, as far as I am able to judge, 
 always in the same meaning. And this is 
 probably the reason why it is so seldom 
 defined or explained. 
 
 Dr Johnson, in the authorities he gives, 
 to shew that the word ieM*e signifies under- 
 standing, soundness of faculties, strength of 
 natural reason, quotes Dr Bentley for what 
 may be called a definition of connnon sense, 
 though probably not intended for that pur- 
 pose, but mentioned accidentally : " God 
 hath endowed mankind with power and 
 abilities, which we call natural light and 
 reason, and common sense." 
 
 It is true that common sense is a popular 
 and not a scholastic word ; and by most of 
 those who have treated systematically of 
 the powers of the understanding, it is only 
 occasionally mentioned, as it is by other 
 writers. Hut I recollect two philosojihical 
 writers, who are exceptions to this remark. 
 One is Buffier, who treated largely of com- 
 mon sense, as a principle of knowledge, 
 above fifty years ago. The other is Bishop 
 Berkeley, who, I think, has laid as much 
 stress upon conmion sense, in opposition to 
 the doctrines of philosoi>hers, as any philo- 
 sopher that has come after him. If the 
 reader chooses to look back to Essay II. 
 chap. 10, he will be satisfied of this, from 
 the quotations there made for another pur- 
 pose, which it is unnecessary here to repeat. 
 
 Men rarely ask what common sense is ; 
 because every man believes hiit. ;lf pos- 
 sessed of it, and "Would tnKe it for an inijiut- 
 ation upon his umlerstanding to be thought 
 tinacquainted with it. Yet I remember 
 two very eminent authors who have put 
 this question ; and it is not improper to hear 
 theirsentiments ujion a subji'ctso freipieiitly 
 mentioned, and so rarely cai.vassed. [.'>2r»] 
 
 f rtdi-.'i^a 1 
 
 It is well known that Lord Shaftesbury 
 gave to one of his Treatises the title of 
 '■ Sensus Communis; an Essay on the 
 Freedom of Wit and Humour, in a Letter 
 to a Friend ;" in which he puts his friend in 
 mind of a free conversation wiih some of 
 their friends on the subjects of morality 
 and religion. Amidst the difi'erent opinions 
 started and maintained with great life and 
 ingenuity, one or other would, every now and 
 then, take the liberty to appeal to conmion 
 sense. Every one allowed the appeal ; no 
 one would ofter to call the authority of the 
 court in question, till a gentleman whose 
 good understanding was never yet brought 
 ni doubt, desired the company, very gravely, 
 that they would tell him what common 
 sense was. 
 
 " If," said he, '' by the word sense, we 
 were to understand opinion and judgment, 
 and by ihe word amnion, the generality or 
 any considerable part of mankind, it would 
 be hard to discover where the sul)ject of 
 common sense could lie ; for that which 
 was according to the sense of one part of 
 mankind, was against the sense of another. 
 And if the majority were to determine com- 
 mon sense, it would change as often as 
 men changed. That in religion, connnon 
 sense was as hard to determine as cath lie 
 or orihiddx. What to one was absurdity, 
 to another was dem(. nitration. 
 
 " In policy, if jdain British or Dutch 
 sense were riglit, Turkish and French must 
 certainly be wrong. And as mere non- 
 sense as passive obedience seemed, we 
 found it to be the connnon sense of a great 
 party amongst ourselves, a greater party 
 in Europe, and perhaps the greatest part 
 of all the world besides. As for morals, 
 the difference was still wider ; for even the 
 philosophers could never agree in one and 
 the same system. A nd some even of our 
 most admired modern philosophers had 
 fairly told us that virtue and vice had no 
 other law or measure than mere fashion and 
 vogue." [52«] 
 
 This is the substance of the gentleman's 
 speech, which, I ajjprehend, explains the 
 meaning of the word perfectly, and contains 
 all that has been said or can be said against 
 the authority of connnon sense, and the 
 propriety of appeals to it. 
 
 As there is no mention of any answer 
 inmiediafely made to this speech, we might 
 be ai)t to conclude that the noble author 
 adopted the sentiments of the intellif;cnt 
 gentleman whose si>((cli he rerite.'i. But 
 the contrary is manifest, from the title of 
 SrnMi.s Cowiniini.s given to bis Essay, from 
 his frequent use of the word, and from the 
 whole tenor of the lOssay. 
 
 'I'lie author appears to have a doulile in- 
 tention in that EHsay, correMponding tti the 
 double title pri'lived toil, (In.' intention
 
 424 
 
 ON THE INTELLECTUAL POWERS. 
 
 [essay 
 
 VI, 
 
 is, to justify the use of wit, humour, and 
 ridicule, in discussing among friends the 
 gravest subjects- " I can very well sup- 
 pose," says he, " men may be frighted 
 out of their wits ; but I have no apprehen- 
 sion they .should be laughed out of them. 
 I can hardly imaguie that, in a pleasant 
 way, they should ever be talked out of their 
 love for socitty, or reasoned out of humanity 
 and common sense." 
 
 The otlier intention, signified by the title 
 Sensu^ Cuinmuiiiti, is carried on band in 
 hand with the first, and is to shew that 
 common sense is not so vague and uncertain 
 a thing as it is represented to be in the 
 Bceptir«al speech before recited. " I will 
 try," su} s he, " what certain knowledge or 
 assurance of things may be recovered in 
 that very way, (to wit, of humour,) by 
 which all certainty, you thought, was lost, 
 and an endless scepticism introduced. " [ 52? ] 
 
 He gives some criticisms upon the word 
 sen.sus commrinis in Juvenal, Horace, and 
 Seneca ; and, after shewing, in a facetious 
 way throughout the treatise, that the fun- 
 damental principles of moi-als, of politics, of 
 criticism, and of every branch of knowledge, 
 are the dictates of common sense, he sums 
 up the whole in these words : — " That some 
 moral and philosophical truths there are 
 so evident in themselves that it would be 
 easier to imagine half mankind run mad, 
 and joined precisely in the same species of 
 folly, than to admit anything as truth 
 which should be advanced against such 
 natural knowledge, fundamental reason 
 and common sense. " And, on taking leave, 
 he adds : — " And now, my friend, sliould 
 you find I had moralised in any tolerable 
 manner, according to common sense, and 
 without canting, I should be satisfied with 
 my performance." 
 
 Another eminent writer who has put the 
 question what common sense is, is Fenelon, 
 the famous Archbishop of Cambray. 
 
 That ingenious and pious author, having 
 had an early prepossession in favour of the 
 Cartesian philosophy, made an attempt to 
 establish, on a sure foundation, the meta- 
 physical arguments which Des Cartes had 
 invented to prove the being of the Deity. 
 For this purpose, he begins with the Carte- 
 sian doubt. He proceeds to find out the 
 truth of his own existence, and then to ex- 
 amine wherein the evidence and certainty 
 of this and other such primary truths con- 
 sisted. This, according to Cartesian prin- 
 ciples, he places in the clearness and dis- 
 tinctness of the ideas. On the contrarj', 
 he places the absurdity of the contrary pro- 
 positions, in their being repugnant to his 
 clear and distinct' ideas. 
 
 To illustrate this, he gives various ex- 
 amples of questions manifestly absurd and 
 ridiculons, which every man of common 
 
 understanding would, at first sight, perceive 
 to be so ; and then goes on to this purpose. 
 
 " What is it that makes these questions 
 ridiculous ? Wherein does this ridicule 
 precisely consist ? It will, perhaps, be 
 replied, that it consists in this, that they 
 shock common sense. But what is this 
 same connnon sense ? It is not the first 
 notions that all men have equally of the 
 same things. [528] This connnon sense, 
 which is always and in all places the same ; 
 which prevents inquiry ; which makes in- 
 quiry in some cases ridiculous ; which, in- 
 stead of inquiring, makes a man laugh 
 whether he will or not ; which puts it out 
 of a man's power to doubt : this sense, 
 which only waits to be consulted — which 
 shews itself at the first glance, and imme- 
 diately discovers the evidence or the absurd- 
 ity of a question — is not this the same that 
 I call my ideas ? 
 
 " Behold, then, those ideas or general 
 notions, which it is not in my power eitlier 
 to contradict or examine, and by which I 
 examine and decide in every case, insomuch 
 that I laugh instead of answering, as often 
 as anything is proposed to me, which is evi- 
 dently contrary to what these imnmtable 
 ideas represent" 
 
 I shall only observe upon this passage, 
 that the interpretation it gives of Des 
 Cartes' criterion of truth, whether just or 
 not, is the most intelligible and the most 
 favourable I have met with. 
 
 I beg leave to mention one passage from 
 Cicero, and to add two or three from late 
 writers, which shew that this word is not 
 become obsolete, nor has changed its 
 meaning. 
 
 " De Oratore," lib. 3 — " Oranes enim 
 tacito quodam sensu, sine ulla arte aut 
 ratione, in artibus ac rationibus, recta ac 
 prava dijudicant. Idque cum faciant in 
 picturis, et in signis, et in aliis cperibus, ad 
 quorum intelligentiam a natura minus hab- 
 ent instrument!, tum multo ostendunt niagis 
 in verborum, numerorum, vocumque judi- 
 cio ; quod ea sint in communibus infixa 
 sensibus ; neque earum rerum quemquam 
 funditus natura voluit expertem." 
 
 " Hume's " Essays and Treatises," vol. 
 
 I- p. 5 " But a philosopher who proposes 
 
 only to represent the common sense of 
 mankind in more beautiful and more engag- 
 ing colours, if by accident he commits a 
 mistake, goes no farther, but, renew ing his 
 appeal to common sense, and the natural 
 sentiments of the mind, returns into the 
 right path, and secures himself from any 
 dangerous illusion." [529] 
 
 Hume's " Enquiry concerning the Prin- 
 ciples of Morals," p. 2 " Those who have 
 
 refused the reality of moral distinctions may 
 be ranked among the disingenuous dis- 
 putants. The only way of converting an 
 
 [ 527-52P]
 
 CHAP. Ji.J 
 
 OF COMMON SENSE. 
 
 425 
 
 antagonist of this kind is to leave him to 
 lumself: for, finding that nobody keeps up 
 the controversy with him, it is probable he 
 vnW at last, of himself, from mere weariness, 
 come over to the side of common sense and 
 reason." 
 
 Priestley's " Institutes," Preliminary 
 Essav, vol. i. p. 27 — " Because common 
 sense is a sufficient guard against many 
 errors in religion, it seems to have been 
 taken for granted that that common sense 
 is a sufficient instructor also, whereas in 
 fact, without positive instruction, men would 
 naturally have been mere savages with 
 respect to religion ; as, without similar in- 
 struction, they would be savages with re- 
 spect to the arts of life and the sciences. 
 Common sense can only be compared to a 
 ; judge ; but what can a judge do without 
 evidence and proper materials from which 
 to form a judgment ?" 
 
 Priestley's '• Examination of Dr Reid," 
 &c. page 127. — " Cut should we, out of 
 complaisance, admit that what has hitherto 
 been called judgment may be called sense, 
 it is makinjr too free with the established 
 signification of words to call it common 
 sense, which, in common acceptation, has 
 long been appropriated to a very different 
 thing — viz , to that capacity for judging of 
 common things that persons of middling 
 capacities are capable of." Page 129. — " I 
 should, therefore, expect that, if a man was 
 60 totally deprived of common sense as not 
 to be able to distinguish truth from false- 
 hood in one case, he would be equally in- 
 capable of distinguishing it in another." 
 [530] 
 
 From this cloud of testimonies, to which 
 hundreds might be added, I apprehend, 
 that whatever censure is thrown upon those 
 who have spoke of comnu'ii sense as a prin- 
 ciple of knowledge, or who have appealed to 
 it in matters that are self-evident, will fall 
 light, when there are so many to share in 
 it. Indeed, the authority of this tribunal 
 is too sacred and venerable, and has pre- 
 scription too long in its favour to be now 
 wuely called in question. Those who are 
 disposed to do so, may remember the shrewd 
 saying of Mr Ilobbes — " When reason is 
 against a man, a man will bo against rea- 
 son." This is equally ai)plicable to com- 
 mon sense. 
 
 From the account I nave given of the 
 meaning of this term, it is easy to judge 
 both of the proper use and of the abuse 
 of it. 
 
 It is absurd to conceive that there can be 
 any ojiposition between reason and com- 
 mon sense." It is indeed the first-jjorii of 
 , Reason ; and, as they are commonly joined 
 
 * Sec above, p. UX), b, note t ; «i><l Mr Stcwart'i 
 ■' F.lemcnU," II. p. i>i.— H. . 
 [.5.30, .'i.SlJ -..-;./pir''' 
 
 together in speech and in writing, they are j 
 inseparable in their nature. jlcv^^ 
 
 We ascribe to reason two offices, or two | ,rs 
 degrees. The first is to judge of things | ][ -'- 
 self-evident ; the second to draw conclusions )/ "" 
 
 that are not self-evident from those that i ^^' 
 arc. The first of these is the province, and ' 
 the sole province, of common sense ; and, ,■▼* 
 
 therefore, it coinciiles with reason in its 
 whole extent, and is only another name for 
 one branch or one degree of reason. Per- J 
 haps it may be said, Why then should you ' 
 give it a particular name, since it is acknow- 
 ledged to be only a degree of reason ? It 
 would be a sufficient answer to this. Why 
 do you abolish a name which is to be found 
 in the language of all civilized nations, and 
 has acquired a right by prescription ? Such 
 an attempt is equally foolish and ineflectual. 
 Every wise man will be apt to think that 
 aname>\liich is found in all languages as 
 far back as we can trace them, is not with- 
 out some use. [531] 
 
 But there is an obvious reason why this 
 degree of reason should have a name ap- 
 propriated to it ; and that is, that, in the 
 greatest part of mankind, no other degree of 
 reason is to be found. It is this degree 
 that entitles them to the denomination of 
 reasonable creatures. It is this degree of 
 reason, and this only, that makes a man 
 capable of managing his own affairs, and 
 answerable for his conduct towards others. 
 There is therefore the best reason why it 
 should have a name appropriated to it. 
 
 These two degrees of reason dift'er in 
 other respects, which would be sufficient to 
 entitle them to distinct names. 
 
 The first is purely the gift of Heaven. 
 And where Heaven has not given it, no 
 education can supjily the want. The se- 
 cond is learned by practice and rules, when 
 the first is not wanting. A man who has 
 cf)mmon sense may bo taught to reason. 
 But, if he has not that gilt, no teaching will 
 make him able either to judge of first prin- 
 ciples or to reason from them. 
 
 I have only this farther to observe, that 
 the province of common sense is more ex- 
 tensive in refutation than in confirmation. 
 A conclusion drawn by a train of just rea- 
 soning from true principles cannot possibly 
 contradict any decision of common sense, 
 because truth will always be consistent 
 with itself. Neither can such a conclu- 
 sion receive any confirmation from com- 
 mon sense, because it is not within its juris- 
 diction. 
 
 But it is possible that, by setting out 
 from false principles, or by an error in 
 reasoning, a man may bo U'd !<• a conclu- 
 sion that contradicts the decisions of com- 
 mon sense. In this case, the conolunon 
 is within the jurisdictitm of common sense, 
 though the reasoniuK on which it wan
 
 426 
 
 ON THE INTELLECTUAL POWERS. 
 
 [kssay VI. 
 
 grounded be not ; and a man of common 
 sense may fairly reject the conclusion with- 
 out being able to shew the error of the rea- 
 eoning that led to it. [532] 
 
 Thus, if a mathematician, by a process 
 of intricate demonstration, in which some 
 false step was made, should bo brought to 
 this conclusion, that two quantities, which 
 are both equal to a third, are not equal to 
 each other, a man of common sense, with- 
 out pretending to be a judge of the demon- 
 stration, is well entitled to reject the con- 
 clusion, and to pronounce it absurd. 
 
 CHAPTER IIL 
 
 SENTIMENTS OF PHILOSOPHERS CONCERNING 
 JUDGMENT. 
 
 A DIFFERENCE about the meaning of a 
 word ought not to occasion disputes among 
 philosophers ; but it is often very proper to 
 take notice of such differences, in order to 
 prevent verbal disputes. There are, in- 
 deed, no words in language more liable to 
 ambiguity than those by which we express 
 the operations of the mind ; and the most 
 candid and judicious may sometimes be led 
 into different opinions about their precise 
 meaning. 
 
 I hinted before what I take to be a pecu- 
 liarity in Mr Locke with regard to the 
 meaning of the word judgment, and men- 
 tioned what, I apprehend, may have led 
 him into it. But let us hear himself. Essay, 
 book iv. chap. 14 : — " The faculty which 
 God has given to man to supply the want 
 of clear and certain knowledge, where that 
 cannot be had, is judgment ; whereby the 
 mind takes its ideas to agree or disagree ; 
 or, which is the same, any proposition to 
 be true or false, without perceiving a de- 
 monstrative evidence in the proofs. Thus 
 the mind has two faculties conversant about 
 truth and falsehood. First, Knowledge, 
 whereby it certainly perceives, and is un- 
 doubtedly satisfied of, the agreement or 
 disagreement of any ideas. Secondbj, 
 Judgment, which is the putting ideas to- 
 gether, or separating them from one an- 
 other in the mind, when their certain agree- 
 ment or disagreement is not perceived, but 
 presumed to be so." [533] 
 
 Knowledge, I think, sometimes signifies 
 things known ; sometimes that act of the 
 mind by which we know them. And in like 
 manner opinion sometimes signifies things 
 believed ; sometimes the act of the mind 
 by which we believe them. But judgment 
 is the faculty which is exercised in both 
 these acts of the mind. In knowledge, we 
 judge without doubting ; in opinion, with 
 some mixture of doubt. But I know no 
 authority, besides that of Mr Locke, for 
 
 calling knowledge a faculty, any more than 
 for calling opinion a faculty. 
 
 Neither do I think that knowledge is 
 confined within the narrow limits which 
 Mr Locke assigns to it ; because the far 
 greatest part of what all men call human 
 knowledge, is in things which neither ad- 
 mit of intuitive nor of demonstrative proof, 
 I have all along used the word judt/ment 
 in a more extended sense than Mr Locke 
 does in the passage above-mentioned. I 
 understand by it that operation of mind by 
 which we determine, concerning anything 
 that may be expressed by a proposition, 
 whether it be true or false. Every propo- 
 sition is either true or false ; so is every 
 judgment. A proposition may be simply 
 conceived without judging of it. But when 
 there is not only a conception of the pro- 
 position, but a mental affirmation or nega- 
 tion, an assent or dissent of the understand- 
 ing, whether weak or strong, that is judg- 
 ment. 
 
 I think that, since the days of Aristotle, 
 logicians have taken the word in that sense, 
 and other writers, for the most part, 
 though there are other meanings, which 
 there is no danger of confounding with this. 
 [534] 
 
 We may take the authority of Dr Isaac 
 Watts, as a logician, as a man who under- 
 stood English, and who had a just esteem 
 of Mr Locke's Essay. Logic. Introd. page 
 5 — " Judgment is that operation of the 
 mind, wherein we join two or more ideas 
 together by one affirmation or negation ; 
 that is, we either affirm or deny (his to be 
 that. So: this tree is hi</h • that horse is not 
 swift ; the mind of man is a thinking beinc; ; 
 mere matter has no tlioKght belonging to it; 
 God is just; good men are of ten miserable in 
 this ivorld ; a righteous governor will make 
 a difference bvtwixt the evil and the gcod ; 
 which sentences are the effect of judgment, 
 and are called propositions." And, Part II. 
 chap. ii. § 9 — " The evidence of sense is, 
 when we frame a proposition according to 
 the dictate of any of our senses. So we 
 judge that gross is g^ecn; that a trumpet 
 gives a pleasant sound ,• thu/ Jire burns ivood; 
 water is soft ; arid iron hard.'''' 
 
 In this meaning, judgment extends to 
 every kind of evidence, probable or certain 
 and to every degree of assent or dissent. 
 It extends to all knowledge as well as to all 
 opinion ; with this difference only, that in 
 knowledge it is more firm and steady, like 
 a house founded upon a rock. In opinion 
 it stands upon a weaker foundation, and is 
 more liable to be .shaken and overturned. 
 
 These differences about the meaning of 
 words are not mentioned as if truth was on 
 one side and error on the other, but as an 
 apology for deviating, in this instance, from 
 the phraseology of Mr Locke, which is, for 
 
 [532-53 1]
 
 CHAP. III.] SENTIMENTS CONCERNING JUDGMENT. 
 
 427 
 
 the most part, accurate and distinct ; and 
 because attention to the different meanings 
 that are put upon words by different authors, 
 is the best way to prevent our mistaking 
 verbal differences for real differences of 
 opinion. 
 
 The common theory concerning ideas 
 naturally leads to a theory concerning 
 judgment, which may be a proper test of its 
 truth ; for, as they are necessarily con- 
 nected, they must stand or fall together. 
 Their connection is thus expressed by Mr 
 Locke, Book IV. chap. 1— "Since the 
 mind, in all its thoughts and reasonings, 
 hath no other immediate object but its own 
 ideas, which it alone does or can con- 
 template, it is evident that our knowledge is 
 only conversant about them. Knowledge 
 then seems to me to be nothing but the 
 perception of the crinnrctio/i ant agreement, 
 or disagreement and repngiiancij, of any of 
 our ideas. In this nlone it consists." [535] 
 
 There can only be one objection to the 
 justice of this inference ; and that is, that 
 the antecedent proposition from which it is 
 inferred seems to have some ambiguity; 
 for, in the first clause of that proposition, 
 the mind is said to have no other immediafe 
 object but its own ideas ; in the second, 
 that it has no other object at all ; that it 
 does or can contemplate ideas alone." 
 
 If the word immediate in the first clause 
 be a mere expletive, and be not intended to 
 limit the generality of the proposition, then 
 the two clauses will be perfectly consistent, 
 the second being only a repetition or expli- 
 cation ot the first ; and the inference that 
 our knowledge is only conversant about 
 ideas will be perfectly just and logical. 
 
 But, if the word immediate in tlie first 
 clause be intended to limit the general i)ro- 
 position, and to imply that the mind has 
 other objects besides its own ideas, though 
 no other immediate objects, then it will not 
 be true that it does or can contemplate ideas 
 alone ; nor will the inference be justly 
 drawn that our knowledge is only conversant 
 about ideas. 
 
 Mr Locke must cither have meant his 
 antecedent proposition, without any limita- 
 tion by the word immediafe, or he must 
 have meant to limit it by that word, and to 
 signify that there are objects of the mind 
 which are not ideas. 
 
 The first of tiiese suppositions appears to 
 me most probable, for several reasons. 
 [530] 
 
 First, Because, when ho purposely de- 
 fines the word idea, in the introduction to 
 the Essay, he says it is whatsoever is the 
 
 * In reference to the polemic that followH, hoc, for 
 a solution, wlint haa been «aid aliovc in regard to the 
 ambiguity of the term rt^;>(7, and Nule It. In regard 
 to the doctrine of Idtiu, as liild by the |ihllo>o|iheri, 
 «ee above, and Note (.', Ko. — i i. 
 
 [.53.5- ./i?] 
 
 object of the understanding when a man 
 thinks, or whatever the mind can be em- 
 ployed about in thinking. Here there is no 
 room left for objects of the mind that are 
 not ideas. The same definition is often 
 repeated throughout the Essav. Some- 
 times, indeed, tlie word immediate is added 
 as in the passage now under consideration ; 
 but there is no intimation made that it ought 
 to be understood when it is not expressed. 
 Now, if it had really been his ojjinion that 
 there are objects of thought which are not 
 ideas, this definition, which is the ground- 
 work of the whole Essay, would have been 
 very improper, and apt to mislead his 
 reader. 
 
 Secondly, He has never attempted to 
 shew how there can be objects of thought 
 which are not immediate objects ; and, 
 indeed, this seems impossible. For, what- 
 ever the object be, the man either thinks of 
 it, or he does not. There is no medium 
 between these. If he thinks of it, it is an 
 immediate object of thought while he thinks 
 of it. If he does not think of it, it is no 
 object of thouglit at all. Every object of 
 thought, therefore, is an immediate object 
 of thought, and the word immediate, joined 
 to objects of thought, seems to be a mere 
 expletive. 
 
 Tliirdly, Tho\i^\ Malebranche and Bishop 
 Berkeley believed that we have no ideas of 
 minds, or of the operations of minds, and 
 that we may think and reason about them 
 without ideas, this was not the opinion of 
 Mr Locke. He thought that tliere are 
 ideas of minds, and of their operations, as 
 well as of the objects of sense ; that the 
 mind perceives nothing but its own ideas, 
 and that all words are tlie signs of ideas. 
 
 A fourth reason is. That to suppose that 
 he intended to limit the antecedent (iroposi- 
 tion by the word immediate, is to impute to 
 him a blunder in reasoning, which I do nt)t 
 think Mr Locke could have connnitted ; 
 for what can be a more glaring paralogism 
 than to infer that, since ideas are partly, 
 though not solely, the objects of thought, it 
 is evident that all our knowledge is only 
 conversant about them. If, on the con- 
 trar}', he meant that ideas are the only ob- 
 jects of thought, then the conclusion drawn 
 is perfectly just and obvious ; and he might 
 very well say, that, since it is idea^oiilg Ih'it 
 the mind does or can contemplate, it is eri- 
 dent that our knuicledge is only conversant 
 about them. |5;{71 
 
 As to the Conclusion itself, I have oidy 
 to observe, that, though he e.v tends it only to 
 what he calls knowleilgo, and not to what 
 lie calls judgment, there is the same reuhon 
 for extending it to both. 
 
 It is true of judgment, as well as of 
 knowli'dge, that it can only 1m> conver.'':int 
 ;iljoiit oV)jtcts of the mind, or alioul lliingH
 
 428 
 
 ON THE INTELLECTUAL POWERS. 
 
 [[ess/ 
 
 \T VI. 
 
 which the mind can contemplate. Judg- 
 ment, as well as knowledge, supposes the 
 conception of tlio object about which we 
 judge ; and to judge of objects that never 
 were nor can be objects of the mind, is evi- 
 dently impossible. 
 
 This, therefore, we may take for granted, 
 that, if knowledge be conversant about ideas 
 only, because there is no other object of the 
 mind, it must be no less certain that judg- 
 ment is conversant about ideas only, for 
 the same reason. 
 
 Mr Locke adds, as the result of his rea- 
 soning, " Knowledge, then, seems to me to 
 be nothing but the perception of the con- 
 nection and agreement, or disagreement 
 and repugnancy, of any of our ideas. In 
 this alone it consists." 
 
 This is a veiy important point, not only 
 on its own account, but on account of its 
 necessary connection with his system con- 
 cerning ideas, which is such as that both 
 must stand or fall together ; for, if there is 
 any part of human knowledge which does 
 not consist in the perception of the agree- 
 ment or disagreement of ideas, it must fol- 
 low that there are objects of thought and 
 of contemplation which are not ideas. 
 1538] 
 
 This point, therefore, deserves to be care- 
 fully examined. With this view, let us 
 first attend to its meaning, which, I think, 
 can hardly be mistaken, though it may 
 need some explication. 
 
 Every point of knowledge, and every 
 judgment, is expressed by a proposition, 
 wherein something is affirmed or denied of 
 the subject of the proposition. 
 
 By perceiving the connection or agree- 
 ment of two ideas, I conceive, is meant per- 
 ceiving the truth of an affirmative proposi- 
 tion, of which the subject and predicate are 
 ideas. In like manner, by perceiving the 
 disagreement and repugnancy of any two 
 ideas, I conceive is meant perceiving the 
 truth of a negative proposition, of which 
 both subject and predicate are ideas. This 
 I take to be the only meanhig the words 
 can bear, and it is confirmed by what Mr 
 Locke says in a passage already quoted in 
 this chapter, that " the mind, taking its 
 ideas to agree or disagree, is the same as 
 taking any proposition to be true or false."' 
 Therefore, if the definition of knowledge 
 given by Mr Locke be a just one, the sub- 
 ject, as well as the predicate of every pro- 
 position, by which any point of knowledge 
 is expressed, must be an idea, and can be 
 nothing else ; and the same must hold of 
 every proposition by which judgment is 
 expressed, as has been shewn above. 
 
 Having ascertained the meaning of this 
 definition of human knowledge, we are 
 next to consider how far it is just. 
 
 First, I would observe that, if the word 
 
 idea be taken in the meaninB- which it had 
 at first among the Pythagoreans and Pla- 
 tonists, and if by knowledge be meant only 
 abstract and general knowledge, (which I 
 believe Mr Locke had chiefly in his view,) 
 I think the proposition is true, that such 
 knowledge consists solely in perceiving the 
 truth of propositions whose subject and 
 predicate are ideas. [539] 
 
 By ideas here I mean things conceived 
 i abstractly, without regard to their existence. 
 We commonly call them abstract notions, 
 abstract conceptions, abstract ideas — the 
 Peripatetics called them universals ; and 
 the Platonists, who knew no other ideas, 
 called them ideas without addition. 
 
 Such ideas are both subject and predicate 
 in every proposition which expresses ab- 
 stract knowledge. 
 
 The whole body of pure mathematics is 
 an abstract science ; and in every mathe- 
 matical proposition, both subject and pre- 
 dicate are ideas, in the sense above explained. 
 Thus, when I say the side of a square is not 
 commensurable to its diagonal — in this 
 proposition the side and the diagonal of a 
 square are the subjects, (for, being a rela- 
 tive proposition, it must have two subjects.) 
 A square, its side, and its diagonal, are 
 ideas, or universals ; they are not indivi- 
 duals, but things predicable of many indi- 
 viduals. Existence is not included in their 
 definition, nor in the conception we form of 
 them. The predicate of the proposition is 
 commensvrahle, which must be an univer- 
 sal, as the predicate of every proposition is 
 so. In other branches of knowledge, many 
 abstract truths may be found, but, for the 
 most part, mixed with others that are not 
 abstract. 
 
 I add, that I apprehend that what is strictly 
 called demonstrative evidence, is to be found 
 in abstract knowledge only. This was the 
 opinion of Aristotle, of Plato, and, I think, 
 of all the ancient philosophers ; and I be- 
 lieve in this they judged right. It is true, 
 we often meet with demonstration in astro- 
 mony, in mechanics, and in other branches 
 of natural philosophy ; but, I believe, we 
 shall always find that such demonstrations 
 are grounded upon principles of supposi- 
 tions, which have neither intuitive nor 
 demonstrative evidence. [540] 
 
 Thus, when we demonstrate that the 
 path of a projectile in vacuo is a parabola, 
 we suppose that it is acted upon with the 
 saroe force and in the same direction 
 through its whole path by gravity. This is 
 not intuitively known, nor is it demon- 
 strable ; and, in the demonstration, we rea- 
 son from the laws of motion, which are 
 principles not capable of demonstration, 
 but grounded on a different kind of evidence. 
 
 Ideas, in the sense above explained, are 
 creatures of the mind ; they are fabricated 
 
 [638-540]
 
 CHAP, in.] SENTIMENTS CONCERNING JUDGMENT 
 
 429 
 
 by its rational powers ; we know their 
 nature and their essence — for they are 
 nothing more than they are conceived to 
 be ; — and, because they are perfectly known, 
 we can reason about them with the highest 
 degree of evidence. 
 
 And, as they are not things that exist, 
 but thing's conceived, thev neither have 
 place nor time, nor are they liable to 
 change. 
 
 When we say that they are in the mind, 
 this can mean no more but that they are 
 conceived by the mind, or that they are 
 objects of thought. The act of conceiving 
 them is, no doubt, in the mind ; the things 
 conceived have no place, because they have 
 not e.Kistence. Thus, a circle, considered 
 ab.stractly, is said figuratively to be in the 
 mind of him that conceives it ; but in no 
 other sense than the city of London or the 
 kingdom of France is said to be in his 
 lainJ when he thinks of those objects. 
 
 Place and time belong to finite things that 
 exist, but not to things that are barely con- 
 ceived. They may be objects of concep- 
 tion to intelligent beings in every place and 
 at all times. Hence the Pythagoreans and 
 Platouists were led to think that they are 
 eternal and omnipresent. If they had ex- 
 istence, they must be so ; for they have no 
 relation to any one place or time, which 
 they have not to every place and to every 
 time. 
 
 The natural prejudice of mankind, that 
 what we conceive must have existence, led 
 those ancient philosophers to attribute ex- 
 istence to ideas ; and by this they were led 
 into all the extravagant and mysterious 
 parts of their system. When it is purged 
 of these, I apprehend it to be the only in- 
 telligible and rational system concerhing 
 ideas. [ 54 1 ] 
 
 I agree with them, therefore, that idea-s 
 are iranuitaliiy tiie same in all times and 
 places ; for this means no more but that a 
 circle is always a circle, and a square always 
 a square. 
 
 I agree with them that ideas are the pat- 
 terns or exemplars by which everything 
 was made that had a beginning : for an 
 intelligent artificer nmst conceive his work 
 before it is made ; he makes it according to 
 that conception ; and the tiling conceived, 
 before it exists, can only be an idea. 
 
 I agree with them that every species of 
 tilings, considered abstractly, is an idea ; 
 and th.-it the idea of tlie species is ni every 
 indiviiliial of the species, without division 
 or multiplication. This, indeed, is expressed 
 somewhat mysteriously, according to the 
 manner of the sect ; but it may easily be 
 explained. 
 
 Every idea is an attribute ; and it is a 
 common way of speaking to say, that the 
 attribute is in every subject of which it may 
 
 L5U-.'il.:^] 
 
 truly be affirmed. Thus, to he above fifty 
 years if age is an attribute or idea. This 
 attribute may be in, or aflirmed of, fifty 
 difterent individuals, and be tiie same in 
 all, without division or multiplication. 
 
 I think that not only every species, but 
 every genus, jiigher or lower, and every 
 attribute considered abstractly, is an idea. 
 These are things conceived without regard to 
 existence ; they are niiiversals, and, there- 
 fore, ideas, according to the ancient mean- 
 ing of that word. [542] 
 
 It is true that, after the Platonists en- 
 tered into disputes with the Peripatetics, in 
 order to defend the existence of eternal 
 ideas, they found it prudent to contract the 
 line of defence, and maintained only that 
 there is an idea of every species of natural 
 things, but not of the genera, nor of things 
 artificial. They were unwilling to multijily 
 beings beyond what was necessary ; but 
 in this, I think, they departed from the 
 genuine principles of their system. 
 
 The definition of a species is nothing 
 but the definition of the geiiUS, with the 
 addition of a specific ditlerence ; and the 
 division of things into species is the work 
 of the mind, as well as their division into 
 genera and classes. A species, a genus, an 
 order, a class, is only a combination of at- 
 tributes made by the mind, and calleil by 
 one name. There is, therefore, the same 
 reason for giving the name of idea to every 
 attribute, and to every species and gemis, 
 whether higher or lower : these are oidy 
 more complex attributes, or combinations 
 of the more simple. And, though it might 
 be improper, without necessity, to multiply 
 beings which they believed to have a real 
 existence, yet, had they seen that ideas 
 are not things that exist, but things that 
 are conceived, they would have a])i)re- 
 hended no danger nor expense from their 
 number. 
 
 Simple attributes, species, and genera, 
 lower or higher, are all things conceived 
 without regard to existence ; they are uni- 
 versals ; they are expressed by general 
 words ; and have an equal title to be called 
 by the name of ideas. 
 
 I likewise a;^ree with those ancient jilii- 
 losoi)hers that ideas are the object, and iho 
 sole object, of science, strictly so called — 
 that is, of demonstrative reasoning. 
 
 And, as ideas are imnuitable, so their 
 agreements and disagreements, and all their 
 relations and attributes, are imnuitable. 
 All mathematical truths are ininiutubly 
 true. Like the ideas about which tliey are 
 conversant, they have no relation to time 
 or jilacc, no dependence upon existiiice or 
 change. That the angles of a plane tri- 
 angle arc equal to two right angles always 
 was, and always will be, true, though no 
 triangle had ever oxiuted. | ^>i'.i ]
 
 430 
 
 ON THE INTELLECTUAL POWERS 
 
 [essay 
 
 VI. 
 
 The same may be said of all abstract 
 truths : on that account they have often 
 been called eternal truths ; and, for the 
 same reason, the Pythagoreans ascribed 
 eternity to the ideas about which they are 
 conversant. They may very properly be 
 called necessary truths ; because it is im- 
 possible they should not be true at all times 
 and in all phices. 
 
 Such is the nature of all truth that can 
 be discovered, by perceiving the agreements 
 and disagreements of ideas, when we take 
 that word in its primitive sense. And that 
 Mr Locke, in his detinition of knowledge, 
 had chiefly in his view abstract truths, we 
 may be led to think from the examples he 
 gives to illustrate it. 
 
 But there is another great class of truths, 
 which are not abstract and necessary, and, 
 therefore, cannot be perceived in tlie agree- 
 ments and disagreements of ideas. These 
 are all the truths we know concerning the 
 real existence of things — the truth of our 
 own existence— of the existence of other 
 things, inanimate, animal, and rational, and 
 of their various attributes and relations. 
 
 These truths may be called contingent 
 truths. I except only the existence and 
 attributes of the Supreme Being, which is 
 the only necessary truth I know regarding 
 existence. 
 
 All otlier beings that exist depend for 
 their existence, and all that belongs to it, 
 upon the will and power of the first cause ; 
 therefore, ne'ther their existence, nor their 
 nature, nor anything that befalls them, is 
 necessary, but contingent. 
 
 But, although the existence of the Deity 
 be necessary, I apprehend we can only de- 
 duce it from contingent truths. The only 
 arguments for the existence of a Deity 
 which I am able to comprehend, are ground- 
 ed upon the knowledge of my own existence, 
 and the existence of other finite beings. 
 But these are contingent truths. [544] 
 
 I believe, therefore, that by perceiving 
 agreements and disagreements of ideas, no 
 contingent truth whatsoever can be known, 
 nor the real existence of anything, not even 
 our own existence, nor the existence of a 
 Deity, which is a necessary truth. Thus I 
 have endeavoured to shew what knowledge 
 may, and what cannot be attained, by per- 
 ceiving the agreements and disagreements 
 of ideas, when we take that word in its 
 primitive sense. 
 
 We are, in the nexl place, to consider, 
 whether knowledge consists in perceiving the 
 agreement or disagreement of ideas, taking 
 ideas in any of the senses in which the word 
 is used by Mr Locke and other modern 
 philosophers. 
 
 L Very often the word idea is used so, 
 that to have the idea of anything is a peri- 
 phrasis for conceiving it. In this sense, an 
 
 idea is not an object of thought, it is thought 
 itself. It is the act of the mind by which 
 we conceive any object. And it is evident 
 that this could not be the meaning which 
 Mr Locke had in view ui his definition of 
 knowledge. 
 
 2. A second meaning of the word idea is 
 that which Mr Locke gives in the intro- 
 duction to his Essay, when he is making an 
 apology for the frequent use of it : — " It be- 
 ing that term, I think, which serves best to 
 stand for whatsoever is the object of the 
 understanding when a man thinks, or what- 
 ever it is which a man can be employed 
 about in thinking." 
 
 By this definition, indeed, everything that 
 can be the object of thought is an idea. 
 The objects of our thoughts may, I tliink, 
 be reduced to two classes. 
 
 The first class comprehends all those 
 objects which we not only can think of, but 
 which we believe to have a real existence : 
 such as the Creator of all things, and all 
 his creatures that fall within our notice. 
 [545] I oan think of the sun and moon, 
 the earth and sea, and of the various animal, 
 vegetable, and inanimate productions with 
 which it hath pleased the bountiful Creator 
 to enrich our globe. I can think of myself, 
 of my friends and acquaintance. I think 
 of the author of the Essay with high esteem. 
 These, and such as these, are objects of the 
 understanding which we believe to have real 
 existence. 
 
 A second class of objects of the under- 
 standing which a man may be employed 
 about in thinking, are things which we either 
 believe never to have existed, or which we 
 think of without regard to their existence. 
 
 Thus, I can think of Don Quixote, of 
 the Island of Laputa, of Oceana, and of 
 Utopia, which I believe never to have ex- 
 isted. Every attribute, every species, and 
 every genus of things, considered abstractly, 
 without any regard to their existence or 
 non-existence, may be an object of the 
 understanding. 
 
 To this second class of objects of the 
 understanding, the name of idea does very 
 properly belong, according to the primitive 
 sense of the word, and I have already con- 
 sidered what knowledge does and what 
 does not consist in perceiving the agree- 
 ments and disagreements of such ideas. 
 
 But, if we take the word idea in so ex- 
 tensive a sense as to comprehend, not only 
 the second, but also the first class of objects 
 of the understanding, it will undoubtedly 
 be true that all knowledge consists in per- 
 ceiving the agreements and disagreements 
 of ideas : for it is impossible that there can 
 be any knowledge, any judgment, any 
 opinion, true or false, which is not employed 
 about the objects of the understanding. 
 But whatsoever is an object of the under- 
 
 f541., 545]
 
 CHAP. 111.] SENTIMENTS CONCERNING JUDGMENT. 
 
 431 
 
 standing is au idea, according to this second 
 meaning of the word. 
 
 Yet I am persuaded that Mr Locke, in 
 his definition of knowledge, did not mean 
 that the word idea should extend to all those 
 things which we commonly consider as ob- 
 jects of the understanding. [o-lG] 
 
 Though Bishop Berkeley believed that 
 sun, moon, and stars, and all material things, 
 are ideas, and nothing but ideas, Mr Locke 
 nowhere professes this opinion. He be- 
 lieved that we liave ideas of bodies, but not 
 that bodies are ideas. In like manner, he 
 believed that we have ideas of minds, but 
 not that minds are ideas. When he in- 
 quired so carefully into the origin of all our 
 ideas, he did not surely mean to find the 
 origin of whatsoever may be the object of 
 the understanding, nor to resolve the origin 
 of everything that may be an object of 
 understanding into sensation and reflec- 
 tion. 
 
 3. Setting aside, therefore, the two mean- 
 ings of the word idea, before mentioned, as 
 meanings which Mr Locke could not have 
 in his view in the definition he gives of 
 knowledge, the only meaning that could be 
 intended in this place is that which I before 
 called the philosophical meaning of the 
 word idea, which hath a reference to the 
 theory commonly received about the manner 
 in which the mind perceives external objects, 
 and in which it remembers and conceives 
 objects that are not present to it. It is a very 
 ancient opinion, and has been very generally 
 received among philosophers, that we can- 
 not perceive or think of such objects im- 
 mediately, but by the medium of certain 
 images or representatives of them really 
 existing in the mind at the time. 
 
 To those images the ancients gave the 
 name of species and phantasms. Modern 
 philosophers have given them the name of 
 ideas- " 'Tis evident," says Mr Locke, 
 book iv., chap. 4, " the niiiid knows not things 
 immediately, but only by tlie intervention 
 of tlie ideas it has of them." And in the 
 same paragraph he puts this question : 
 " IIow shall the mind, when it perceives 
 notliing but its own ideas, know that they 
 agree with things themselves ?" [547] 
 
 This theory I have already considered, 
 in treating of perception, of memory, and 
 of conception. The reader will there find 
 the reasons tliat lead me to think that it 
 has no solid foundation in reason, or in 
 attentive reflection upon those operations 
 of our minds ; that it contradicts tlie im- 
 mediate dictates of our natural faculties, 
 which are of higher autliority than any 
 tiieory ; that it lias takon its rise from the 
 i same prejudices wiiich led all the ancient 
 I philosophers to think that the Deity could 
 not make tliis world witliout some eternal 
 matter to wurk ujion, and which led tlic 
 
 Pythagoreans and Platonists to think that 
 he could not conceive the plan of the world 
 he was to make without eternal ideas really 
 existing as patterns to work by ; and tliat 
 this theory, when its necessary consequences 
 are fairly pui-sued, leads to absolute scep- 
 ticism, though those consequences were not 
 seen by most of the philosophers who have 
 adopted it. 
 
 I have no intention to repeat what nas 
 before been said upon those points ; but 
 only, taking ideas in this sense, to make 
 some observations upon the definition which 
 Mr Locke gives of knowledge. 
 
 First, If all knowledge consists in per- 
 ceiving the agreements and disagreements 
 of ideas — that is, of representative images of 
 things existing in the mind — it obviously 
 follows that, if there be no such ideas, there 
 can be no knowledge. So that, if there 
 should be found good reason for giving up 
 this philosophical hypothesis, all knowledge 
 must go along with it. 
 
 I hope, however, it is not so : and that, 
 though this hypothesis, like many others, 
 should totter and fall to the ground, know- 
 ledge will continue to stand firm upon a 
 more permanent basis. [548] 
 
 The cycles and epicycles of the ancient 
 astronomers were for a thousand years 
 thought absolutely necessary to explain 
 the motions of the heavenly bodies. Yet 
 now, when all men believe them to have 
 been mere fictions, astronomy has not fallen 
 with them, but stands upon a more rational 
 foundation than before. Ideas, or images 
 of things existing in the mind, have, for a 
 longer time, been thought necessary for 
 explaining the operations of the understand- 
 ing. If they should likewise at last be 
 found to be fictions, human knowledge and 
 judgment would sufi'er nt)tliing by being 
 disengaged from an unwieldy hypothesis. 
 Mr Locke surely did not look upon the ex- 
 istence of ideas as a philoisophical hypo- 
 thesis. He thought that we are conscious 
 of their existence, otherwise he would not 
 have made the existence of all our know- 
 ledge to depend upon the existence of ideas. 
 
 Secondly, Supposing this hypothesis to 
 be true, I agree with Mr Locke that it is 
 an evident and necessary conseiiuence that 
 our knowledge can bo conversant about 
 ideas only, and must consist in perceiving 
 their attributes and relations. For notliing 
 can be more evident than this, that all 
 knowledge, and all judgment and opinion, 
 nuist be about things wliich are or may be 
 immediate olijocts of our thought. What 
 cannot be the object of thougiit, or the 
 object of the mind in tiiiiiking, cannot be 
 the object of knowledge or of o|)iiiioii. 
 
 Everything we can know of any object, 
 must be either some attribute of tlie object, 
 or some relation it bears to some oilier
 
 432 
 
 ON THE INTELLECTUAL POWERS. 
 
 [^ESSAY VI. 
 
 object or objects. By the agreements and 
 disagreements of objects, I apprehend Mr 
 Locke intended to express both their attri- 
 butes and their relations. If ideas then be 
 the only objects of thought, the consequence 
 is necessary, that they must be the only 
 objects of knowledge, and all knowledge 
 must consist in perceiving their agreements 
 and disagreements — that is, their attributes 
 and relations. 
 
 The use I would make of tliis conse- 
 quence, is to shew that the hypothesis must 
 be false, from which it necessarily follows. 
 For if we have any knowledge of things 
 that are not ideas, it will follow no less 
 evidently, that ideas are not the only objects 
 of our thoughts. [549] 
 
 Mr Locke has pointed out the extent and 
 limits of human knowledge, in his fourth 
 book, with more accuracy and judgment 
 than any philosopher had done before ; but 
 he has not confined it to the agreements 
 and disagreements of ideas. And I cannot 
 help thinking that a great part of that book 
 is an evident refutation of the principles 
 laid down in the beginning of it. 
 
 Mr Locke did not believe that he himself 
 was an idea ; that his friends and acquaint- 
 ance were ideas ; that the Supreme Being, 
 to speak with reverence, is an idea ; or 
 that the sun and moon, the earth and the 
 sea, and other e-sxternal objects of sense, are 
 ideas. He believed that he had some cer- 
 tain knowledge of all those objects. His 
 knowledge, therefore, did not consist solely 
 in perceiving the agreements and disagree- 
 ments of his ideas ; for, surely, to perceive 
 the existence, the attributes, and relations 
 of things, which are not ideas, is not to per- 
 ceive the agreements and disagreements of 
 ideas. And, if things which are not ideas be 
 objects of knowledge, they must be objects of 
 thought. On the contrary, if ideas be the 
 only objpcts of thought, there can be no 
 knowledge, either of our own existence, or 
 of the existence of external objects, or of 
 the existence of a Deity. 
 
 This consequence, as far as concerns the 
 exibtence of external objects of sense, was 
 afterwards deduced from the theory of ideas 
 by Bishop Berkeley with the clearest evi- 
 dence ; and that author chose ratlier to 
 adopt the consequence than to reject the 
 theory on which it was grounded. But, 
 with I'egard to the existence of our own 
 minds, of other minds, and of a Supreme 
 Mind, the Bishop, that he might avoid the 
 consequence, rejected a part of the theory, 
 and maintained that we can think of minds, 
 of their attributes and relations, without 
 ideas. [550] 
 
 Mr Hume saw very clearly the conse- 
 quences of this theory, and adopted them 
 in his speculative moments ; but candidly 
 acknowledges that, in the common busi- 
 
 ness of life, he found himself under a neces- 
 sity of believing with the vulgar. His 
 "Treatise of Human Nature" is the only 
 system to which the theory of ideas leads ; 
 and, in my apprehension, is, in all its parts, ^ 
 the necessary consequence of that theory. 
 
 Mr Locke, however, did not see all the 
 consequences of that theory ; he adopted it 
 without doubt or examination, carried along 
 by the stream of philosophers that went 
 before him ; and his judgment and good 
 sense have led him to s^ay many things, and 
 to believe many things, that cannot be re- 
 conciled to it. 
 
 He not only believed his own existence, 
 the existence of external things, and the 
 existence of a Deity ; but he has shewn 
 very justly how we come by the knowledge 
 of these existences. 
 
 It might here be expected that he should 
 have pointed out the agreements and dis- 
 agreements of ideas from which these exist- 
 ences are deduced ; but this is impossible, 
 and he has not even attempted it. 
 
 Our own existence, he observes, we know 
 inluiltv bf; but this intuition is not a percep- 
 tion of the agreement or disagreement of 
 ideas ; for the subject of the proposition, / 
 exist, is not an idea, but a person. 
 
 The knowledge of external objects of 
 sense, he observes, we can have only bysensa- 
 tim. This sensation he afterwards expresses 
 more clearly by the testimony of our senses, 
 which are the proper and sole judi/es of this 
 thinij; whose testimony is the yreatest assur. 
 ance we can possibly have, and to ivhich 
 our faculties can attain. This is perfectly 
 agreeable to the common sense of mankind, 
 and is perfectly understood by those who 
 never heard of the theory of ideas. Our 
 senses testify immediately the existence, 
 and many of the attributes and relations of 
 external material beings ; and, by our con- 
 stitution, we rely with assurance upon their 
 testimony, without seeiiing a reason for 
 doing so. This assurance, Mr Locke ac- 
 knowledges, deserves the name of know- 
 ledge. But those external things are not 
 ideas, nor are their attributes and relations 
 the agreements and disagreements of ideas, 
 but the agreements and disagreements of 
 things which are not ideas. [551] 
 
 To reconcile this to the theory of ideas, 
 Mr Locke says, Thnt it is the actual reci iv- 
 illy of ideas from wiih'iut that gives us notice 
 of the existence of those external things. 
 
 This, if understood literally, would lead 
 us back to the doctrine of Aristotle, that 
 our ideas or species come from without 
 from the external objects, and are the image 
 or form of those objects. But Mr Locke, 
 I believe, meant no more by it, but that 
 our ideas of sense must have a cause, and 
 that we are not the cause of them our- 
 selves. 
 
 [54&-551]
 
 CHAP, m.] SENTIMENTS CONCERNING JUDGMENT. 
 
 433 
 
 Bishop Berkeley acknowledges all this, 
 and shews very clearly that it does not 
 ati'ord the least shadow of reason for the 
 belief of any material object — nay, that 
 there can be nothing external that lias any 
 resemblance to our ideas but the ideas of 
 other minds. 
 
 It is evident, therefore, that tlie agree- 
 ments and disagreements of ideas can give 
 us no knowledge of the existence of any 
 material thing. If any knowledge can be 
 attained of things which are not ideas, that 
 knowledge is a perception of agreements 
 and disagreements ; not of ideas, but of 
 things that are not ideas. 
 
 As to the existence of a deity, though 
 Mr Locke was aware that Des Cartes, and 
 many after him, had attempted to prove it 
 merely from the agreements and disagree- 
 ments of ideas ; yet " he thought it an 
 ill way of establishing that truth, and si- 
 lencing Atheists, to lay the whole stress of so 
 important a point upon that sole founda- 
 tion." And, therefore, he proves this 
 point, witli great strength and solidity, from 
 our own existence, and the existence of the 
 sensible parts of the universe. [552] By 
 memory, Mr Locke says, we have the 
 knowledge of the past existence of several 
 tilings. But all conception of past exist- 
 ence, as well as of external existence, is 
 irreconcileable to the theory of ideas ; be- 
 cause it supposes that there may be imme- 
 diate objects of thought, which are not ideas 
 presently existing in the mind. 
 
 I conclude, therefore, that, if we have 
 any knowledge of our own existence, or of 
 the existence of what we see about us, or of 
 the existence of a Supreme Being, or if 
 we have any knowledge of things past by 
 memory, that knowledge cannot consist in 
 perceiving the agreements and disagree- 
 ments of ideas. 
 
 This conclusion, indeed, is evident of 
 itself. For, if knowledge consists solely in 
 the perception of the agreement or disagree- 
 ment of ideas, there can be no knowledge of 
 any projiosition, which does not express 
 some agreement or disagreement of ideas; 
 consequently, there can be no knowledge of 
 any proposition, which expresses either the 
 existence, or the attributes or relations of 
 things, which are not ideas. If, therefore, 
 the theory of ideas be true, there can be no 
 knowledge of anything but of ideas. And, 
 on the other hand, if we have any know- 
 ledge of anything besides ideas, that theory 
 must be false. 
 
 There can be no knowledge, no judgment 
 or opinion about things which are not im- 
 mediate objects of thought This I take to 
 be self-evideiit. If, therefore, ideas be the 
 only immediate objects of thought, they 
 must be the only things in nature of wjiich 
 wc can iiave any knowledge, and about 
 
 which we can have any judgment or 
 opinion. 
 
 This necessary consequence of the com- 
 mon doctrine of ideas Mr Hume saw, and 
 has made evident in his " Treatise of 
 Human Nature ;" but the use he made of 
 it was not to overturn the theory with which 
 it is necessarily connected, but to overturn 
 all knowledge, and to leave no ground to 
 believe anything whatsoever. If Mr Locke 
 had seen this consequence, there is reason 
 to think that he would have made another 
 use of it. [553] 
 
 That a man of Mr Locke's judgment and 
 penetration did not perceive a consequence 
 so evident, seems indeed very strange ; and 
 I know no other account that can be given of 
 it but this — that the ambiguity of the word 
 idea has misled him in this, as in several 
 other instances. Having at first defined 
 ideas to be whatsoever is the object of the 
 understanding when we think, he takes it 
 very often in that unlimited sense ; and so 
 everything that can be an object of thought 
 is an idea. At other times, he uses the 
 word to signify certain representative images 
 of things in the mind, which philosophers 
 have supposed to be immediate objects of 
 thought. At other times, things conceived 
 abstractly, without regard to their exist- 
 ence, are called ideas. Philosoj.hy is much 
 indebted to Mr Locke for his observations 
 on the abuse of words. It is pity he did 
 not apply these observations to the word 
 idea, the ambiguity and abuse of which has 
 very much hurt his excellent Essay. 
 
 There are some other opinions of philo- 
 sophers concerning judgment, of which I 
 think it unnecessary to say much. 
 
 Mr Hume sometimes adopts Mr Locke's 
 opinion, that it is the perception of the 
 agreement or disagreement of our ideas ; 
 sometimes he maintains that judgment and 
 reasoning resolve themselves into concep- 
 tion, and are nothing but particular ways 
 of conceiving objects ; and he says, that ao 
 opinion or belief may most accurately be 
 defined, a liveli/ idea related to or ossociated 
 iviih a present impression. — Treatise of Hu- 
 man Nature, vol. I. page 172. 
 
 I have endeavoured before, in the first 
 chapterof this Essay, to shew that judgment 
 is an operation of mind specifically distinct 
 fromthe bare conception of an object. Ihave 
 also considered his notion of belief, in treating 
 of the theories concerning memory. [554] 
 
 Dr Hartley says — " That assent and dis- 
 sent must come under the notion of ideas, 
 being only those very complex internal 
 feelings which adhere by association to such 
 clusters of words us arc called propositions 
 in general, or atiirmations and negations in 
 particular." 
 
 'I'liis, if I understand its meaning, agrees 
 with the opinion of Mr Hume, above men- 
 
 '2 »
 
 434 
 
 ON THK INTELLECTUAL POWERS. 
 
 [essay VI. 
 
 tioned, and has therefore been before con- 
 sidered. 
 
 Dr Priestly has given another definition 
 of judgment: — " It is nothing more than 
 the perception of the universal concurrence, 
 or the perfect coincidence of two ideas ; or 
 the want of that concurrence or coinci- 
 dence." This, I think, coincides with Mr 
 Locke's definition, and therefore has been 
 already considered. 
 
 There are many particulars which deserve 
 to be known, and which might very properly 
 be considered in this Essay on judgment ; 
 concerning the various kinds of propositions 
 by which our judgments are expressed; 
 their subjects and predicates ; their con- 
 versions and oppositions : but as these are 
 to be found in every system of logic, from 
 Aristotle down to the present age, I think 
 it unnecessary to swell this Essay with the 
 repetition of what has been said so often. 
 The remarks which have occurred to me 
 upon what is commonly said on these points, 
 as well as upon the art of syllogism ; the 
 utility of the school logic, and the improve- 
 ments that may be made in it, may be found 
 in a " Short Account of Aristotle's Logic, 
 with Remarks," which Lord Kames has 
 honoured with a place in his " Sketches of 
 the History of Man." [555] 
 
 CHAPTER IV. 
 
 OF FIRST PRINCIPLES IN GENERAL. 
 
 One of the most important distinctions of 
 our judgments is, that some of them are 
 intuitive, others grounded on argument. 
 
 It is not in our power to judge as we 
 •will. The judgment is carried along neces- 
 sarily by the evidence, real or seeming, 
 which appears to us at the time. But, in 
 propositions that are submitted to our 
 judgment, there is this great difference — 
 some are of such a nature that a man of 
 ripe understanding may apprehend them 
 distinctly, and perfectly understand their 
 meaning, without finding himself under any 
 necessity of believing them to be true or 
 false, probable or improbable. The judg- 
 ment remains in suspense, until it is in- 
 clined to one side or another by reasons or 
 arguments. 
 
 But there are other propositions which 
 are no sooner understood than they are be- 
 lieved. The judgment follows the appre- 
 hension of them necessarily, and both are 
 equally the work of nature, and the result 
 of our original powers. There is no search- 
 ing for evidence, no weighing of arguments ; 
 the proposition is not deduced or inferred 
 from another ; it has the light of truth in 
 itself, and has no occasion to borrow it 
 from another. 
 
 Propositions of the last kind, when they 
 are used in matters of science, have com- 
 monly been called axioms ; and on what- i 
 ever occasion they are used, are called ^Vs« 
 principles, principles of common sense, com' \ 
 mnn notions, self-evident truihs. Cicero , 
 calls them nalura judicia,judicia communi- 
 bus hominum sensibus infixa. Lord Shaftes- 
 bury expresses them by the words, natural 
 knowledge, fundamental reason, and common 
 sense. [556] 
 
 What has been said, I think, is sufficient 
 to distinguish first principles, or intuitive 
 judgments, from those which may be as- 
 cribed to the power of reasoning ; nor is it 
 a just objection against this distinction, that 
 there may be some judgments concerning 
 which we may be dubious to which class 
 they ought to be referred. There is a real 
 distinction between persons within the 
 house, and those that are without ; yet it 
 may be dubious to which the man belongs 
 that stands upon the threshold. 
 
 The power of reasoning — that is, of draw- i 
 ing a conclusion from a chain of premises — '; 
 may with some propriety be called an art. 
 " All reasoning," says Mr Locke, " is 
 search and casting about, and requires 
 pains and application." It resembles the 
 power of walking, which is acquired by use 
 and exercise. Nature prompts to it, and 
 has given the power of acquiring it ; but 
 must be aided by frequent exercise before 
 we are able to walk. After repeated efforts, 
 much stumbling, and many falls, we learn 
 to walk ; and it is in a similar manner that 
 we learn to reason. 
 
 But the power of judging in self-evident 
 propositions, which are clearly understood, 
 may be compared to the power of swallow- 
 ing our food. It is purely natural, and there- 
 fore common to the learned and the un- 
 learned, to the trained and the untrained. 
 It requires ripeness of understanding, and 
 freedom from prejudice, but nothing else. 
 
 I take it for granted that there are self- 
 evident principles. Nobody, I think, de- 
 nies it. And if any man were so sceptical 
 as to deny that there is any proposition 
 that is self-evident, I see not how it would 
 be possible to convince him by reasoning. 
 
 But yet there seems to be great difference 
 of opinions among philosophers about first 
 principles. What one takes to be self-evi- 
 dent, another labours to prove by argu- 
 ments, and a third denies altogether. [557] 
 
 Thus, before the time of Des Cartes, it 
 was taken for a first principle, that there is 
 a sun and a moon, an earth and sea, which 
 really exist, whether we think of them or 
 not. Des Cartes thought that the exist- 
 ence of those things ought to be prpved by 
 argument ; and in this he has been follow- 
 ed by Malebranche, Arnauld, and Locke. 
 They have all laboured to prove, by very 
 
 [555-557^
 
 CllAP, 
 
 IV.] 
 
 OF FIRST PRINCIPLES IN GENERAL. 
 
 43o 
 
 weak reasoning, tlie existence of external 
 olyects of sense ; and Berkeley and Hume, 
 sensible of the weakness of their arguments, 
 liave been led to deny their existence alto- 
 gether. 
 
 The ancient philosophers granted, that 
 all knowledge must be grounded on first 
 principles, and that there is no reasoning 
 w thout them. The Peripatetic philosophy 
 was redundant rather than deficient in fi.st 
 principles. Perhaps the abuse of them in 
 that ancient system may have brought 
 them into discredit in modern times ; for, 
 as the best things may be abused, so that 
 abase is apt to give a disgust to the thing 
 itself ; and as one extreme often leads into 
 the opposite, this seems to have been the 
 case in the respect paid to first principles 
 in ancient and modern times. 
 
 Des Cartes thought one principle, express- 
 ed in one word, cogito, a sufficient foundation 
 for his whole system, and asked no more. 
 
 Mr Locke seems to think first principles 
 of very small use. Knowledge consisting, 
 according to him, in the perception of the 
 agreement or disagreement of our ideas ; 
 when we have clear ideas, and are able to 
 compare them together, we may always fa- 
 bricate first principles as often as we have 
 occasion for them. Such differences we find 
 among philosophers about first principles. 
 
 It is likewise a question of some moment, 
 whether the differences among men about 
 first principles can be brought to any issue ? 
 When in disputes one man maintains that 
 to be a first principle which another denies, 
 conmiosily both parties appeal to common 
 sense, and so the matter rests. Now, is 
 there no way of discussing this appeal ? Is 
 there no mark or criterion, whereby first 
 principles that are truly such, may be dis- 
 tinguished from those that assume the cha- 
 racter without a just title ? I shall humbly 
 offer in the following propositions what 
 ajjpears to me to be agreeable to truth in 
 these matters, always ready to change my 
 opinion upon conviction. [558] 
 
 1. First, I hold it to be certain, and even 
 demonstrable, that all knowledge got by 
 reasoning must be built upon first princi- 
 ples.* 
 
 This is as certain as that every house 
 must have a foundation. The power of 
 reasoning, in tliis respect, resembles the 
 uieclianical i>ower3 or engines ; it must 
 liave a fixed point to rust ujion, otherwise 
 it spends its fierce in the air, and produces 
 no effect. 
 
 When we examine, in the way of ana- 
 lysis, the evidence of any proposition, either 
 we find it self-evident, or it rests upon one 
 or more propositions that support it. The 
 /' eame thing may he said of tlie propositions 
 
 * So Amtotle, pJunVjT— U. 
 [i5ft, 559] 
 
 that support it, and of those that support 
 them, as far back as we can go. But we 
 cannot go back in this track to infinity. 
 Where then must this analysis stop ? It I) 
 is evident that it must stop only when we 
 come to propositions which support all that 
 are built upon them, but are tliemselves 
 supported by none — that is, to self-evident 
 propositions. 
 
 Let us again consider a synthetical proof of 
 any kind, where we begin with the premises, 
 and pursue a train of consequences, until we 
 come to the last conclusion or thing to be 
 proved. Here we must begin, either with 
 self-evident propositions or with such as have 
 been already proved. When the last is the 
 case, the proof of the propositions, thus as- 
 sumed, is a part of our proof; and the 
 proof is deficient without it. Suppose then 
 the deficiency supplied, and the proof com- 
 pleted, is it not evident that it must set out 
 with self-evident propositions, and that the 
 whole evidence must rest upon them ? So 
 that it appears to be demonstrable that, 
 without first principles, analytical reasoning 
 could have no end, and synthetical reason- 
 ing could have no beginning ; and that 
 every conclusion got by i-easoning must 
 rest with its whole weight upon first princi- 
 ples, as the building does upon its founda- 
 tion, [559] 
 
 2. A second proposition is. That some 
 first principles yield conclusions that are 
 certain, others such as are probable, in va- 
 rious degrees, from the highest probability 
 to the lowest. 
 
 In just reasoning, the strength or weak- 
 ness of the conclusion will always corre- 
 spond to that of the principles on which it is 
 grounded. 
 
 In a matter of testimony, it is self-evi- 
 dent that the testimony of two is better 
 than that of one, supposing them equal in 
 character, and in their means of knowledge ; 
 yet the simjjle testimony may be true, and 
 that which is preferred to it may be false. 
 
 When an experiment has succeeded in 
 several trials, and the circumstances have 
 been marked with care, there is a self-evi- 
 dent probability of its succeeding in a new 
 trial ; but there is no certainty. The pro- 
 bability, in some cases, is much greater 
 than in others ; because, in some c;vses, it 
 is nmch easier to observe all the circum- 
 stances that may liave infiuence upon the 
 event than in others. And it is possible 
 that, after many experiments made with 
 care, our expectation may be frustrated in 
 a succeeding one, by the variation of some 
 circumstance that has not, or perhaps 
 could not be observed. 
 
 Sir Isaac Newton has laid it down as a 
 first principle in natural i)hiIosophy, that a 
 property which has been found in all bodies 
 upon which we have had access to make 
 
 2k2
 
 436 
 
 ON THE INTELLECTUAL POWERS. 
 
 ["essay VI. 
 
 experiments, and which has always been 
 found in its quantity to be in exact propor- 
 to the quantity of matter in every body, is 
 to be held as an universal property of mat- 
 ter. [560] 
 
 This principle, as far as I know, has 
 never been called in question. The evi- 
 dence we have, that all matter is divisible, 
 movable, solid, and inert, is resolvable 
 into this principle ; and, if it be not true, 
 we cannot have any rational conviction that 
 all matter iias those properties. From the 
 same principle that great man has shewn 
 that we have reason to conclude that all 
 bodies gravitate towards each other. 
 
 This principle, however, has not that 
 kind of evidence which mathematical axioms 
 have. It is not a necessary truth, whose 
 contrary is impossible ; nor did Sir Isaac 
 ever conceive it to be such. And, if it 
 should ever be found, by just experiments, 
 that t)iere is any part in the composition of 
 some bodies which has not gravity, the 
 fact, if duly ascertained, must be admitted 
 as an exception to the general law of gra- 
 vitation. 
 
 In games of chance, it is a first principle 
 that every side of a die has an equal chance 
 to be turned up ; and that, in a, lotterj', 
 every ticket has an equal chance of being 
 drawn out. From such first principles as 
 these, which are the best we can have in 
 such matters, we may deduce, by demon- 
 strative reasoning, the precise degree of 
 probability of every event in such games. 
 
 But the principles of all this accurate 
 and profound reasoning can never yield a 
 certain conclusion, it being impossible to 
 supply a defect in the first principles by any 
 accuracy in the reasoning that is grounded 
 upon them. As water, by its gravity, can 
 rise no higher in its course than the foun- 
 tain, however artfully it be conducted ; so 
 no conclusion of reasoning can have a 
 greater degree of evidence than the first 
 principles from which it is drawn. 
 
 From these instances, it is evident that, 
 as there are some first principles that yield 
 conclusions of absolute certainty, so there 
 are others that can only yield probable con- 
 clusions ; and that the lowest degree of 
 probability must be grounded on first prin- 
 ciples as well as absolute certainty.* 
 [561] 
 
 3. A ihird proposition is, That it would 
 contribute greatly to the stability of human 
 knowledge, and consequently to the im- 
 provement of it, if the first principles upon 
 which the various parts of it are grounded 
 were pointed out and ascertained. 
 
 We have ground to think so, both from 
 facts, and from the nature of the thing. 
 
 There are two branches of human know- 
 
 * Compare Stewart's "Elements," ii. p. 38.— H. 
 
 ledge in which this method has been followed 
 — to wit, mathematics and natural philoso- 
 phy ; in mathematics, as far back as we have 
 books. It is in this science only, that, for 
 more than two thousand years since it be- 
 gan to be cultivated, we find no sects, no 
 contrary systems, and hardly any disputes ; 
 or, if there have been disputes, they have 
 ended as soon as the animosity of par- 
 ties subsided, and have never been again 
 revived. The science, once firmly esta- 
 blished upon the foundation of a few axioms 
 and definitions, as upon a rock, has grown 
 from age so age, so as to become the loftiest 
 and the most solid fabric that human rea- 
 son can boast.* 
 
 Natural philosophy, till less than two 
 hundred years ago, remained in the same 
 fluctuating state with the other sciences. 
 Every new system pulled up tlie old by 
 the roots. The system-builders, indeed, 
 were always willing to accept of the aid 
 of first principles, when they were of their 
 side ; but, finding them insufficient to sup- 
 port the fabric which their imagination had 
 raised, they were only brought in as auxi- 
 liaries, and so intermixed with conjectures, 
 and with lame inductions, that their sys- 
 tems were like Nebuchadnezzar's image, 
 whose feet were partly of iron and partly 
 of clay. 
 
 Lord Bacon first delineated the only so- 
 lid foundation on which natural philoso- 
 phy can be built ; and Sir Isaac Newton 
 reduced the principles laid down by Bacon 
 into three or four axioms, which he calls 
 regnlce philosophandi. From these, toge- 
 ther with the phenomena observed by the 
 senses, which he likewise lays down as 
 first principles, he deduces, by strict rea- 
 soning, the propositions contained in the 
 third book of his "Principia," and in his 
 " Optics ;" and by this means has raised a 
 fabric in those two branches of natural 
 philosophy, which is not liable to be shaken 
 by doubtful disputation, but stands im- 
 movable upon the basis of self-evident 
 principles. [562] 
 
 This fabric has been carried on by the 
 accession of new discoveries ; but is no 
 more subject to revolutions. 
 
 The disputes about riiateria prima, sub- 
 stantial forms. Nature's abhorring a va- 
 cuum, and bodies having no gravitation 
 in their proper place, are now no more. 
 The builders in this work are not put to the 
 necessity of holding a weapon in one hand 
 while they build with the other ; their 
 whole employment is to carry on the work. 
 
 Yet it seems to be very probable, that, if 
 natural philosophy had not been reared upon 
 this solid foundation of self-evident princi- 
 ples, it would have been to this day a field 
 
 See Stewart's '' Elements," ii. 
 
 p. 43.-H. 
 [560, 562]
 
 CHAP. 
 
 ,v.] 
 
 OF FIRST PRINCIPLES IN GENERAL. 
 
 437 
 
 of battle, wherein every inch of ground 
 would have been disputed, and notbing fixed 
 and determined. 
 
 I acknowledge that mathematics and na- 
 tural philosophy, especially the former, 
 have this advantatje of most other sciences, 
 that it is less difficult to form distinct and 
 determinate conceptions of the objects 
 about which they are employed ; but, as 
 this difficulty is not insuperable, it affords 
 a good reason, indeed, why other sciences 
 should have a longer infancy ; but no rea- 
 son at all why they may not at last arrive 
 at maturity, by the same steps as those of 
 quicker growth. 
 
 The facts I have mentioned may there- 
 fore lead us to conclude, that, if in other 
 branches of philosophy the first principles 
 were laid down, as has been done in ma- 
 thematics and natural philosophy, and the 
 subsequent conclusions grounded upon them, 
 this would make it much more easy to dis- 
 tinguish what is solid and well supported 
 from the vain fictions of human fancy. [5C3] 
 
 But, laying aside facts, the nature of the 
 thing leads to the same conclusion. 
 
 For, when any system is grounded upon 
 first principles, and deduced regularly from 
 them, we have a thread to lead us through 
 the labyrinth. The judgment has a distinct 
 and determinate object. The heterogeneous 
 parts being separated, can be examined each 
 by itself. 
 
 The whole system is reduced to axioms, 
 definitions, and deductions. These are ma- 
 terials of very different nature, and to be 
 measured by a very different standard ; and 
 it is much more easy to judge of each, taken 
 « by itself, than to judge of a mass wherein 
 they are kneaded together without distinc- 
 tion. Let us consider how we judge of each 
 of them. 
 
 First, As to definitions, the matter is very 
 easy. They relate only to words, and differ- 
 ences about them may produce different 
 ways of speaking, but can never produce 
 different ways of tliinking, while every man 
 keeps to his own definitions. 
 
 liut, as there is not a more plentiful source 
 of fallacies in reasoning than men's using 
 the same word sometimes in one sense and 
 at other times in another, the best means 
 of preventing such fallacies, or of detecting 
 them when they are committed, is defi- 
 nitions of words as accurate as can be 
 given. 
 
 Secoiidli/, As to deductions drawn from 
 principles granted on both sides, I do not 
 see how they can long be a matter of dis- 
 pute among men who are not blinded by 
 prejudice or partiality ; for the rules of 
 reasoning by whicii inferences may be drawn 
 from premises have been for two thousand 
 years fixed with great unanimity. No man 
 pretends to dispute the rules of reasonmg 
 [.56.3-565'] 
 
 laid down by Aristotle and repeated by 
 every writer in dialectics- [564] 
 
 And we may observe by the way, that 
 the reason why logicians have been so una- 
 nimous in determining the rules of reason- 
 ing, from Aristotle down to this day, seems 
 to be, that they were by that great genius 
 raised, in a scientific manner, from a few 
 definitions and axioms. It may farther be 
 observed, that, when men differ about a 
 deduction, whether it follows from certain 
 j)remises, this I think is always owing to 
 their differing about some first principle. 
 I shall explain this by an example. 
 
 Suppose that, from a thing having begun 
 to exist, one man infers that it must have 
 had a cause ; another man does not admit 
 the inference. Here it is evident, that the 
 first takes it for a self-evident principle, that 
 everything which begins to exist must have 
 a cause. The other does not allow this to 
 be self-evident. Let them settle this point, 
 and the dispute will be at an end. 
 
 Thus, I think, it appears, that, in matters 
 ofscience, if thetennsbe properly explained, 
 the first principles upon which the reason- 
 ing is grounded be laid down and exposed 
 to examination, and the conclusions re- 
 gularly deduced from them, it might be 
 expected that men of candour and capacity, 
 who love truth, and have patience to ex- 
 amine things coolly, might come to unani- 
 mity with regard to the force of the deduc- 
 tions, and that their differences might be 
 reduced to those they may have about first 
 principles, 
 
 4. A fourth proposition is. That Nature 
 hath not left us destitute of means whereby 
 the candid and honest part of mankind may 
 be brought to unanimity when they happen 
 to differ about first principles. [565] 
 
 When men differ about things that are 
 taken to be first principles or self-evident 
 truths, reasoning seems to be at an end. 
 Kach party appeals to common sense. When 
 one man's common sense gives one deter- 
 mination, another man's a contrary deter- 
 mination, there seems to be no remedy but 
 to leave every man to enjoy his own opinion. 
 This is a common observation, and, I be- 
 lieve, a just one, if it be rightly understood. 
 
 It is in vain to reason with a man who 
 denies the first principles on which the rea- 
 soning is grounded. Thus, it would be in 
 vain to attempt the proof of a proposition 
 in Euclid to a man who denies the axioms. 
 Indeed, wo ought never to reason with men 
 who deny first j)rinci])les from obstinacy 
 and unwillingness to yield to reason- 
 But is it not possible, that men who really 
 love truth, and are oj)en to conviction, may 
 difler about first i)rinciples ? 
 
 I think it is possible, and that it cannot, 
 without great want of charity, be denied to 
 be possible.
 
 438 
 
 ON THE INTELLECTUAL POWERS. 
 
 [_ESSAY VI- 
 
 When this happens, every man who be- 
 lieves that there is a real distinction between 
 truth and error, and that the faculties which 
 God has given us are not in their nature 
 fallacious, must be convinced that there is 
 a defect or a perversion of judgment on 
 the one side or the other. 
 
 A man of candour and humility will, in 
 such a case, very naturally suspect his own 
 judgment, so far as to be desirous to enter 
 into a serious examination, even of what 
 he has long held as a first principle. He 
 will think it not impossible, that, although 
 his heart be upright, his judgment may have 
 been perverted, by education, by authority, 
 by party zeal, or by some other of the com- 
 mon causes of error, from the influence of 
 which neither parts nor integrity exempt 
 the human understanding. [5ti6] 
 
 In such a state of mind, so amiable, and 
 so becoming every good man, has Nature 
 left him destitute of any rational means by 
 which lie may be enabled, either to correct 
 his judgment if it be wrong, or to confirm 
 it if it be right ? 
 
 I hope it is not so. I hope that, by the 
 means which nature has furnished, con- 
 troversies about first principles may be 
 brought to an issue, and that the real lovers 
 of truth may come to unanimity with regard 
 to them. 
 
 It is true that, in other controversies, 
 the process by which the truth of a propo- 
 sition is discovered, or its falsehood detected, 
 is, by shewing its necessary connection with 
 first principles, or its repugnancy to them. 
 It is true, likewise, that, when the contro- 
 versy is, whether a proposition be itself a 
 first principle, this process cannot be ap- 
 plied. The truth, therefore, in controversies 
 of this kind, labours under a peculiar dis- 
 advantage. But it has advantantages of 
 another kind to compensate this. 
 
 I. For, in the first place, in such con- 
 troversies, every man is a competent judge; 
 and therefore it is difficult to impose upon 
 mankind. 
 
 To judge of first principles, requires no 
 more than a sound mind free from preju- 
 dice, and a distinct conception of the question. 
 The learned and the unlearned, the phi- 
 losopher and the day-labourer, are upon a 
 level, and will pass the same judgment, 
 when they are not misled by some bias, or 
 taught to renounce their understanding 
 from some mistaken religious principle. 
 
 In matters beyond the reacli of common 
 understandin,--, the many are led by the 
 few, and willingly yield to their authority. 
 But, in matters of common sense, the few 
 must yield to the many, when local and 
 temporary prejudices are removed. No 
 man is now moved by the subtle arguments 
 of Zeno against motion, though, perhaps, he 
 knows not how to answer them, [.567] 
 
 The ancient sceptical system furnishes a 
 remarkable instance of this truth. That 
 system, of which Pyrrho'was reputed the 
 father, was carried down, through a succes- 
 sion of ages, by very able and acute philo- 
 sophers, who taught men to believe nothing 
 at all, and esteemed it the highest pitch of 
 human wisdom to vvithhold assent from 
 every proposition whatsoever. It was sup- 
 ported with very great subtilty and learning, 
 as we see from the writings of Sextus Em- 
 piricus, the only author of that sect whose 
 writings have come down to our age. The 
 assault of the sceptics against all science 
 seems to have been managed with more art 
 and address than the deteuce of the dog- 
 matists. 
 
 Yet, as this system was an insult upon the 
 common sense of mankind, it died away of 
 itself; and it would be in vain to attempt 
 to revive it. The modern scepticism is very 
 difi'erent from the ancient, otherwise it would 
 not have been allowed a hearing ; and, when 
 it has lost the grace of novelty, it will die 
 away also, though it should never be refuted. 
 
 The modern scepticism, I mean that of 
 Mr Hume, is built upon principles which 
 were very generally maintained by philo- 
 sophers, though they did not see that they 
 led to scepticism. Mr Hume, by tracing, 
 with great acuteness and. ingenuity, the con- 
 sequences of principles commonly received, 
 has shewn that they overturn all knowledge, 
 and at last overturn themselves, and leave 
 the mind in perfect suspense, 
 
 2. Secondly, We may observe that opin- 
 ions which contradict first principles, are 
 distinguished, from other errors, by this : — 
 That they are not only false but absurd ; 
 and, to discountenance absurdity. Nature 
 hath given us a particular emotion — to wit, 
 that of ridicule — which seems intended for 
 this very purpose of putting out of counte- 
 nance what is absurd, either in opinion or 
 practice. [568] 
 
 This weapon, when properly applied, cuts 
 with as keen an edge as argument. Nature 
 hath furnished us with the first to expose 
 absurdity ; as with the last to refu'e error. 
 Both are well fitted for their several offices, 
 and are equally friendly to truth when pro- 
 perly used. 
 
 Both may be abused to serve the cause 
 of error ; but the same degree of judgment 
 which serves to detect the abuse of argu- 
 ment in false reasoning, serves to detect the 
 abuse of ridicule when it is wrong directed. 
 
 Some have, from nature, a happier talent 
 for ridicule than others ; and the same 
 thing holds with regard to the talent of 
 reasoning. Indeed, I conceive there is 
 hardly any absurdity, which, when touched 
 with the pencil of a Lucian, a Swift, or a 
 Voltaire, would not be put out of counte- 
 nance, when there is not some religious 
 
 [566-568]
 
 CHAP. 
 
 IV.] 
 
 OF FIRST PRINCIPLES IN GENERAL. 
 
 439 
 
 panic, or very powerful prejudice, to blind 
 the undcrstauding. 
 
 But it must be acknowledged that the 
 emotion of ridicule, even when most natu- 
 ral, may be stifled by an emotion of a con- 
 trary nature, and cannot operate till that 
 is removed. 
 
 Tlius, if the notion of sanctity is annexed 
 to an object, it is no longer a laughable 
 matter ;' and this visor must be pulled off 
 before it appears ridiculous. Hence we 
 see, that notions which appear most ridicu- 
 lous to all who consider them coolly and in- 
 differently, have no such appearance to 
 those who never thought of them but under 
 the impression of religious awe and dread. 
 
 Even where religion is not concerned, 
 the novelty of an opinion to those who are 
 too fond of novelties ; the gravity and 
 solemnity with which it is introduced ; the 
 opinion we have entertained of the author ; 
 its apparent connection with principles 
 already embraced, or subserviency to in- 
 terests which we have at heart ; and, above 
 all, its being fixed in our minds at that time 
 of life when we receive implicitly what we 
 are taught — may cover its absurdity, and 
 fascinate the understanding for a time. 
 [569] 
 
 But, if ever we are able to view it naked, 
 and stripped of those adventitious circum- 
 stances from which it borrowed its import- 
 ance and authority, the natural emotion of 
 ridicule will exert its force. An absurdity 
 can be entertained by men of sense no longer 
 than it wears a mask. When any man is 
 found who has the skill or the boldness to 
 pull off the mask, it can no longer bear the 
 light ; it slinks into dark corners for a while, 
 and then is no more heard of, but as an ob- 
 ject of ridicule. 
 
 Thus I conceive, that first principles, 
 which are really the dictates of common 
 sense, and directly opposed to absurdities 
 in opinion, will always, from the constitu- 
 tion of human nature, support themselves, 
 and gain rather than lose ground among 
 mankind. 
 
 3. Thirdly, It may be observed, that, al- 
 though it is contrary to the nature of first 
 principles to admit of direct or apodirlit-nt 
 proof; yet there are certain ways of reason- 
 ing even about them, by which those that 
 are just and solid may be confirmed, and 
 those that are false may be detected. It 
 may here be proper to mention some of the 
 topics from which we may reason in matters 
 of this kind. 
 
 First, It is a good urgnment ad hominem, 
 if it can be shewn that a first principle 
 which a man rejects, stands ujion the same 
 footing with others which he admits : for, 
 when this is the cise, he must be guilty of 
 an inconsistency who holds the one and 
 rejects the other. 
 
 Thus the faculties of consciousness, of 
 memory, of external sense, and of reason, 
 are all equally the gifts of nature. No good 
 reason can be assigned for receiving the 
 testimony of one of theni, which is not of 
 equal force with regard to the others. The 
 greatest sceptics admit the testimony of 
 consciousness, and allow that what it testi- 
 fies is to be held as a first principle. If, 
 therefore, they reject the immediate testl 
 mony of sense or of memory, they are 
 guilty of an inconsistency. [570] 
 
 Secondly, A first principle may admit of 
 a proof ad absurdum. 
 
 In this kind of ])roof, which is very com- 
 mon in mathematics, we suppose the con- 
 tradictory proposition to be true. We trace 
 the consequences of that supposition in a 
 train of reasoning ; and, if we find any of 
 its necessary consequences to be manifestly 
 absurd, we conclude the supposition from 
 which it followed to be false ; and, there* 
 fore its contradictory to be true. 
 
 There is hardly any proposition, especially 
 of those that may clann the character of 
 first principles, that stands alone and un- 
 connected. It draws many others along 
 with it in a chain that cannot be broken. 
 He that takes it up must bear the burden 
 of all its consequences ; and, if that is too 
 heavy for him to bear, he must not pretend 
 to take it up. 
 
 Thirdly, I conceive that the consent of 
 ages and nations, of the learned and un- 
 learned, ought to have great authority with 
 regard to first principles, where every man 
 is a competent judge. 
 
 Our ordinary conduct in life is built upon 
 first principles, as well as our speculations 
 in philosophy ; and every motive to action 
 supposes some belief. When we find a 
 general agreement among men, in principles 
 that concern human life, this must have 
 great authority with every sober mind that 
 loves truth. 
 
 It is pleasant to observe the fruitless 
 pains which Bishop Berkeley takes to shew 
 that his system of the non-existence of a 
 material world did not contradict the senti- 
 ments of the vulgar, but those only of the 
 philosophers. 
 
 With good reason he dreaded more to 
 oppose the authority of vulj^ar opinion in a 
 mutter of this kind, than all the schools of 
 philosophers. [57 1 ] 
 
 Here, perhaps, it will be said. What has 
 authority to do in matters of opinion ? Is 
 truth to be determined by most votes ? Or 
 is authority to be again raised out of its 
 grave to tyrannise over nninkind ? 
 
 I am aware that, in this age, .in advo- 
 cate for authority has a very unlavourable 
 plea ; but I wish" to give no more toautlior- 
 ity than is its due. 
 
 Most justly do we hononr the names of
 
 440 
 
 ON THE INTELLECTUAL POWERS. 
 
 [essay 
 
 VI. 
 
 those benefactors to mankind who have con- 
 tributed more or less to break the yoke of 
 that authority which deprives men of the 
 natural, the unalienable right of judging 
 for themselves; but, while we indulge a 
 just animosity against this authority, and 
 against all who would subject us to its 
 tyranny, let us remember how common the 
 folly is, of going from one faulty extreme 
 into the opposite. 
 
 Authority, though a very tyrannical mis- 
 tress to private judgment, may yet, on some 
 occasions, be a useful handmaid. This is 
 all she is entitled to, and this is all I plead 
 in her behalf. 
 
 The justice of this plea will appear by 
 putting a case in a science, in which, of all 
 sciences, authority is acknowledged to have 
 least weight. 
 
 Suppose a mathematician has made a 
 discovery in that science which he thinks 
 important ; that he has put his demonstra- 
 tion in just order ; and, after examining it 
 with an attentive eye, has found no flaw in 
 it, I would ask, Will there not be still in 
 his breast some diffidence, some jealousy, 
 lest the ardour of invention may have made 
 him overlook some false step ? This must 
 be granted. [572] 
 
 He commits his demonstration to the ex- 
 amination of a mathematical friend, whom 
 he esteems a competent judge, and waits 
 with impatience the issue of his judgment. 
 Here I would ask again. Whether the verdict 
 of his friend, according as it is favourable 
 or unfavourable, will not greatly increase or 
 diminish his confidence in his own judgment ? 
 Most certainly it will, and it ought. 
 
 If the judgment of his friend agree with 
 his own, especially if it be confirmed by two 
 or three able judges, he rests secure of his 
 discovery without farther examination ; but, 
 if it be unfavourable, he is brought back 
 into a kind of suspense, until the part that 
 is suspected undergoes a new and a more 
 rigorous examination. 
 
 I hope what is supposed in this case is 
 agreeable to nature, and to the experience 
 of candid and modest men on such occa- 
 sions ; yet here we see a man's judgment, 
 even in a mathematical demonstration, con- 
 scious of some feebleness in itself, seeking 
 the aid of authority to support it, greatly 
 strengthened by that authority, and hardly 
 able to stand erect against it, without some 
 new aid. 
 
 Society in judgment, of those who are 
 esteemed fair and competent judges, has 
 effects very similar to those of civil society : 
 it gives strength and courage to every indi- 
 vidual ; it removes that timidity which is 
 as naturally the companion of solitary judg- 
 ment, as of a solitary man in the state of 
 nature. 
 
 . Let us judge for ourselves, therefore ; but 
 
 let us not disdain to take that aid from the 
 authority of other competent judges, which 
 a mathematician thinks it necessary to take 
 in that science which, of all sciences, has 
 least to do with authority. 
 
 In a matter of common sense, every man 
 is no less a competent judge than a mathe- 
 matician is iu a mathematical demonstra- 
 tion ; and there must be a great presump- 
 tion that the judgment of mankind, in such 
 a matter, is the natural issue of those facul- 
 ties which God hath given them. Such a 
 judgment can be erroneous only when there 
 is some cause of the error, as general as the 
 error is. When this can be shewn to be the 
 case, I acknowledge it ought to have its due 
 weight. But, to suppose a general devia- 
 tion from truth among mankind in things 
 self-evident, of which no cause can be 
 assigned, is highly unreasonable. [573] 
 
 Perhaps it may be thought impossible 
 to collect the general opinion of men upon 
 any point whatsoever ; and, therefore, that 
 this authority can serve us in no stead in 
 examining first principles. But I appre- 
 hend that, in many cases, this is neither 
 impossible nor difficult. 
 
 Who can doubt whether men have uni- 
 versally believed the existence of a mate- 
 rial world ? Who can doubt whether men 
 have universally believed that every change 
 that happens in nature must have a cause ? 
 Who can doubt whether men have uni- 
 versally believed, that there is a right and 
 a wrong in human conduct ; some things 
 that merit blame, and others that are en- 
 titled to approbation ? 
 
 The universality of these opinions, and 
 of many such that might be named, is suf- 
 ficiently evident, from the whole tenor of 
 human conduct, as far as our acquaintance 
 reaches, and from the history of all ages 
 and nations of which we have any records. 
 
 There are other opinions that appear to 
 be universal, from what is common in the 
 structure of all languages. 
 
 Language is the express image and pic- 
 ture of human thoughts ; and from the 
 picture we may draw some certain conclu- 
 sions concerning the original. 
 
 We find in all languages the same parts 
 of speech ; we find nouns, substantive and 
 adjective ; verbs, active and passive, in 
 their various tenses, numbers, and moods. 
 Some rules of syntax are the same in all 
 languages. 
 
 Now, what is common in the structure 
 of languages, indicates an uniformity of 
 opinion in those things upon which that 
 structure is grounded. [574] 
 
 The distinction between substances, and 
 the qualities belonging to them ; between 
 thought and the being that thinks ; be- 
 tween thought and the objects of thought ; 
 is to be found in the structure of all lan- 
 
 [572-571]
 
 CHAP, v.] FIRST PRINCIPLES OF CONTINGENT TRUTHS. 
 
 441 
 
 guages. And, therefore, systems of philo- 
 sophy, which abolish those distiuctions, wage 
 war with the common sense of mankind. 
 
 We are apt to imagine that those who 
 formed languages were no metaphysicians ; 
 but the tirst principles of all sciences are 
 the dictates of common sense, and lie open 
 to all men ; and every man who has con- 
 sidered the structure of language iu a phi- 
 losophical light, will find iniallible proofs that 
 those who have framed it, and those who 
 use it with understanding have the power 
 of making accurate distinctions, and of form- 
 ing general conceptions, as well as philoso- 
 phers. Nature has given those powers to 
 all men, and they can use them when occa- 
 sions require it, but they leave it to the 
 philosophers to give names to them, and to 
 descant upon their nature. In like manner, 
 nature has given eyes to all men, and they 
 can make good use of them ; but the struc- 
 ture of the eye, and the theory of vision, is 
 the business of philosophers. 
 
 Fourthly, Opinions that appear so early 
 in the minds of men that they cannot be 
 the effect of education or of false reason- 
 ing, have a good claim to be considered as 
 first principles. Thus, the belief we Iiave, 
 that the persons about us arc living and in- 
 telligent beings, is a belief for which, per- 
 haps, we can give some reason, when we 
 are able to reason ; but we had this belief 
 before we could reason, and before we could 
 learn it by instruction. It seems, there- 
 fore, to be an immediate effect of our con- 
 stitution. 
 
 The last topic I shall mention is, when 
 an opinion is so necessary in the conduct of 
 life, that, without the belief of it, a man 
 must be led into a thousand absurdities in 
 practice, such an opinion, when we can 
 give no other reason for it, may safely be 
 taken for a first principle. [575] 
 
 Tims I have endeavoured to shew, that, 
 although first principles are not capable of 
 direct proof, yet difi'erences, that may hap- 
 pen with regard to them among men of 
 candour, are not witliout remedy ; that 
 Nature has not left us destitute of means 
 by which we may discover errors of this 
 kind ; and that there are ways of reason- 
 ing, with regard to first principles, by which 
 those that are truly such may be distin- 
 guished from vulgar errors or prejudices. 
 
 CHAPTER V. 
 
 THK FIRST PRl.N'CIPLES OF CONTINGENT 
 TRUTHS- 
 
 " SURELV," says Bishop Berkeley, '' it is 
 a work w«;ll deserving our pains to make 
 a strict inquiry concerning the first princi- 
 j)lc-8 of knowledge ; to sift and examine 
 \61&, 576] 
 
 them on all sides." What was said in the 
 last chapter is intended both to shew the 
 importance of this inquiry, and to make it 
 more easy. 
 
 But, in order that such an inquiry may be 
 actually made, it is necessary that the first 
 principles of knowledge be distinguished 
 from other truths, and presented to view, 
 that they may be sifted and examined on 
 all sides. In order to this end, I shall 
 attempt a detail of those I take to be such, 
 and of the reasons why I think them entitled 
 to that character. [576] 
 
 If the enumeration should appear to some 
 redundant, to others deficient, and to others 
 both— if things which I conceive to be first 
 principles, should to others appear to be 
 vulgar errors, or to be truths which derive 
 their evidence from other truths, and there- 
 fore not first principles — in these things 
 every man must judge for himself. I shall 
 rejoice to see an enumeration more perfect 
 in any or in all of those respects ; being 
 persuaded that the agreement of men of 
 judgment and candour iu first principles 
 would be of no less consequence to the ad- 
 vancement of knowledge in general, than 
 the agreement of mathematicians in the 
 axioms of geometry has been to the ad- 
 vancement of that science. 
 
 The truths that fall within the compass 
 of human knowledge, whether they be self- 
 evident, or deduced from those that are . 
 self-evident, may be reduced to two classes. \ 
 They are either necessary and immutable ' 
 truths, whose contrary is impossible ; or 
 they are contingent and mutable, depend- 
 ing upon some effect of will and power, 
 which had a beginning, and may have an 
 end. 
 
 That a cone is the third part of a cylin- 
 der of the same base and the same altitude, 
 is a necessary truth. It depends not upon 
 the will and power of any being. It is im- 
 mutably true, and the contrary impossible. 
 That the sun is the centre about which the 
 earth, and the other |)lanets of our sys-tem, 
 perform their revolutions, is a truth ; but 
 it is nut a necessary truth. It depends 
 upon the power and will of that Being who 
 made the sun and all the planets, and who 
 gave them those motions that seemed best 
 to him. 
 
 If all truths were necessary truths, there 
 would be no occasion for different tenses in 
 the verbs by which they are expressed. 
 What is true in the present time, wtuld bo 
 true in the past and future ; and there 
 would bo no change or variation of aip. thing 
 in nature. 
 
 We use the present tense in expressing 
 necessary triitlis ; but it is only bt^cause 
 there is no flexion of tjio verb which in- 
 cjucles all times. When I say that three 
 is the half of six, 1 use tlie present tense
 
 442 
 
 ON THE INTELLECTUAL POWERS. 
 
 [essay VI. 
 
 only ; but I mean to express not only what 
 now is, but what always was, and always will 
 be ; and so every proposition is to be under- 
 stood by which we mean to express a neces- 
 sary truth- Contingent truths are of an- 
 other nature. As they are mutable, they 
 may be true at one time, and not at an- 
 other ; and, therefore, the expression of 
 them must include some point or period of 
 time. [577] 
 
 If language had been a contrivance of 
 philosophers, they would probably have 
 given some flexion to the indicative mood 
 of verbs, which extended to all times past, 
 present, and future ; for such a flexion only 
 would be fit to express necessary proposi- 
 tions, which have no relation to time. But 
 there is no language, as far as I know, in 
 wliich such a flexion of verbs is to be found. 
 Because the thoughts and discourse of men 
 are seldom employed about necessary truth'^, 
 but commonly about such as are contin- 
 gent, languages are fitted to express the 
 last rather than the fiist. 
 
 Tlie distinction commonly made between 
 abstract truths, and those that express mat- 
 ters of fact, or real existences, coincides in 
 a great measure, but not altogether, with 
 that between necessary and contingent 
 truths. The necessary truths that fall 
 within our knowledge are, for the most part, 
 abstract truths. We must except the ex- 
 istence and nature of the Supreme Being, 
 which is necessary. Other existences are 
 the effects of will and power. They had a 
 beginning, and are mutable. Their nature 
 is such as the Supreme Being was pleased 
 to give them. Their attributes and rela- 
 tions must depend upon the nature God has 
 given tliem, the powers with which he has 
 endowed them, and the situation in which 
 he hath placed them. 
 
 The conclusions deduced by reasoning 
 from t rst principles, will commonly be ne- 
 cessary or contingent, according as the 
 principles are from which they are drawn. 
 On the one hand, I take it to be certain, 
 that whatever can, by just reasoning, be 
 inferred from a principle that is necessary, 
 must be a necessary truth, and that no 
 contingent truth can be inferred from prin- 
 ciples that are necessary. • [578] 
 
 Thus, as the axioms in mathematics are 
 all necessary truths, so are all the conclu- 
 sions drawn from them ; that is, the whole 
 b dy of that science. But from no mathe- 
 matical truth can we deduce the existence 
 of anything ; not even of the objects of the 
 science. 
 
 On the other hand, I apprehend there 
 are very few cases in which we can, from 
 principles that are contingent, deduce trutl.s 
 that are necessary. I can only recollect 
 
 * Sec Stewart's '< Kloinents," ii. p. 3^ 
 
 One maiance of this kind — namely — that, 
 from the existence of things contingent and 
 mutable, we can infer the existence of an 
 immutable aud eternal cause of them. 
 
 As the minds of men are occupied much 
 more about truths that are contingent than 
 about those that are necessary, I shall first 
 endeavour to point out the principles uf the 
 former kind. 
 
 1. Firat, then, I hold, as a first principle, 
 the existence of everything of which 1 am 
 conscious. 
 
 Consciousness is an operation of the 
 understanding of its own kind, and cannot 
 be logically defined. The objects of it are 
 our present pains, our pleasures, our hopes, 
 our fears, our desires, our doubts, our 
 thoughts of every kind ; in a word, all the 
 passions, and all the actions and operations 
 of our own minds, while they are present. 
 We may remember them when tliey are 
 past ; but we are conscious of them only 
 while they are present. 
 
 When a man is conscious of pain, he is 
 certain of its existence ; when he is con- 
 scious tliat he doubts or believes, he is 
 certain of the existence of those operations. 
 
 But the irresistible conviction he has of 
 the reality of those operations is not the 
 effect of reasoning ; it is immediate and 
 intuitive. The existence therefore of those 
 passions and operations of our minds, of 
 which we are conscious, is a first principle, 
 which nature requires us to believe upon 
 her authority. [679] 
 
 If I am asked to prove that I cannot be 
 deceived by consciousness — to prove that it 
 is not a fallacious sense — I can find nc proof. 
 I cannot find any antecedent truth from 
 which it is deduced, or upon which its evi- 
 dence depends. It seems to disdain any 
 such derived authority, and to claim my 
 assent in its own right. 
 
 If any man could be found so frantic aa 
 to deny that he thinks, while he is conscious 
 of it, I may wonder, I may laugh, or I may 
 pity him, but I cannot reason the matter 
 with him. We have no common principles 
 from which we may reason, aud therefore 
 can never join issue in an argument. 
 
 This, I think, is the only principle of 
 common sense that has never directly been 
 called in question. * It seems to be so firmly 
 rooted in the minds of men, as to retain its 
 authority with the greatest sceptics. Mr 
 Hume, after annihilating body and mind, 
 time and space, action and causation, and 
 even his own mind, acknowledges the reality 
 of the thoughts, sensations, and passions of 
 which he is conscious. 
 
 * It could not possibly I e called in question. For, 
 in doubting the I'lCt of his consciousness, the sceptic 
 must at leas' affirm the fact of his doubt; but to 
 attirm a doubt is to affirm the consciousness of it ; 
 thedou t would, theielore, be self-contradictory — 
 ! c, annihilate itself. — H. 
 
 [577-579]
 
 CHAP. V.J FIRST PRINCIPLES OF CONTINGENT TRUTHS. 
 
 443 
 
 No philosopher has attempted, by any 
 hypothesis, to account for this consciousness 
 of our own thoughts, and the certain know- 
 ledge of their real existence which accom- 
 panies it. By this they seem to acknow- 
 ledge that this at least is an original power 
 of the mind ; a power by which we not only 
 have ideas, but original judgments, and the 
 knowledge of real existence. 
 
 I cannot reconcile this immediate know- 
 ledge of the operations of our own minds 
 with Mr Locke's theory, that all know- 
 ledge consists in perceiving the agreement 
 and disagreement of ideas. What are the 
 ideas, from whose comparison the knowledge 
 of our own thoughts results ? Or what are 
 the agreements or disagreements which con- 
 vince a man that he is in pain when he 
 feels it ? [580] 
 
 Neither can I reconcile it with Mr Hume's 
 theory, that to believe the existence of any- 
 thing, is nothing else than to have a strong 
 and lively conception of it ; or, at most, 
 that belief is only some modification of the 
 idea which is the object of belief. For, not 
 to mention that propositions, not ideas, are 
 the object of belief, in all that variety of 
 thoughts and passions of which we are con- 
 scious we believe the existence of the weak 
 as well as of the strong, the faint as well as 
 the lively. No modification of the opera- 
 tions of our minds disposes us to the least 
 doubt of their real existence. 
 
 As, therefore, the real existence of our 
 thoughts, and of all the operations and feel- 
 ings of our own minds, is believed by all 
 men — as we find ourselves incapable of 
 doubting it, and as incapable of offering any 
 proof of it — it may justly be considered as a 
 first principle, or dictate of common sense. 
 But, although this principle rests upon 
 no other, a very considerable and import- 
 ant branch of human knowledge rests upon 
 it. 
 
 For from this source of consciousness is 
 derived all that we know, and indeed all 
 that we can know, of the structure and of 
 the powers of our own minds ; from which 
 we may conclude, that there is no branch 
 of knowledge tliat stands upon a firmer 
 foundation ; for surely no kind of evidence 
 can go beyond that of consciousness. 
 
 How does it come to pass, then, that in 
 this branch of knowledge there are so many 
 and so contrary systems ? so many subtile 
 controversies tliat are never brought to an 
 issue ? and so little fixed and determined ? 
 Is it possible that philosophers should differ 
 most where they have the surest moans of 
 agreement — where everything is built upon 
 a species of evidence which all men ac- 
 
 fuiesce in, and hold to be the most certain ? 
 501] 
 This strange pluenomenon may, I think, 
 be accounted for, if we distinguish between 
 [580 582] 
 
 consciousness and reflection, which are ofteo 
 improperly confounded " 
 
 The first is common to all men at all 
 times ; but is insufficient of itself to give us 
 clear and distinct notions of the opera- 
 tions of which we are conscious, and of 
 their mutual relations and minute distinc- 
 tions. The second — to wit, attentive reflec- 
 tion upon those operations, making them 
 objects of thought, surveying them atten- 
 tively, and examining them on all sides — is 
 so far from being common to all men, that it 
 is the lot of very few. The greatest part 
 of men, either through want of capacity, or 
 from other causes, never reflect attentively 
 upon the operations of their own minds. 
 The habit of this reflection, even in those 
 whom nature has fitted for it, is not to be at- 
 tained without much pains and practice. 
 
 We can know nothing of the immediate 
 objects of sight, but by the testimony of our 
 eyes ; and I apprehend that, if mankind 
 had found as great difficulty in giving at- 
 tention to the objects of sight, as they find 
 in attentive reflection upon the operations 
 of their own minds, our knowledge of the 
 first might have been in as backward a state 
 as our knowledge of the last. 
 
 But this darkness will not last for ever. 
 Light will arise upon this benighted part of 
 the intellectual globe. When any man is 
 so happy as to delineate the powers of the 
 human mind as they really are in nature, 
 men that are free from prejudice, and cap- 
 able of reflection, will recognise their own 
 features in the picture ; and then the wonder 
 will be, how things so obvious could be so 
 long wrapped up in mystery and darkness ; 
 how men could be carried away by false 
 theories and conjectures, when the truth 
 was to be found in their own breasts if they 
 had but attended to it. 
 
 2. Another first principle, I think, is, 
 That the t/wui/h/s of which I am c<inf:ci'us, 
 are /he thouyhts of a being tchich I call 
 
 MYSELF, mt/ MIND, TO'/ PERSON. [582] 
 
 The thoughts and feelings of which we are 
 conscious are continually changing, and the 
 thought of this moment is not the thought 
 of the last ; but something which I call my. 
 self, remains under this change of thought. 
 This self has the same relation to all the 
 successive thoughts I am conscious of — they 
 are all my thoughts ; and every thought 
 which is not my thought, must be the 
 thought of some other person. 
 
 If any man asks a proof of this, I confess 
 I can give none ; there is an evidence in the 
 proposition itself wliii-h I am unable to re- 
 sist. Shall I think that thought can stand 
 by itself without a thinking being ? or that 
 ideiis cjui feel pleasure or pain ? My nature 
 dictates to me that it is impossible. 
 
 * Coinpnrr alwvp.pp. 239, b, V.W, a —II.
 
 444 
 
 ON THE INTELLECTUAL POWERS. 
 
 [ESSAV VI. 
 
 And that nature lias dictated the same to 
 all men, appears from the structure of all 
 languages : for in all languages men have 
 expressed thinking, reasoning, willing, lov- 
 ing, hating, by personal verbs, which, from 
 their nature, require a person who thinks, 
 reasons, wills, loves, or hates. From which 
 it appears, that men have been taught by 
 nature to believe that thought requires a 
 thinker, reason a reasoner, and love a lover. 
 
 Here we must leave Mr Hume, who con- 
 ceives it to be a vulgar error, that, besides 
 the thoughts we are conscious of, there is a 
 mind which is the sulject of those thoughts. 
 If the mind be anything else than impres- 
 sions and ideas, it must be a word without 
 a meaning. The mind, therefore, accord- 
 ing to this philosopher, is a word which 
 signifies a bundle of perceptions ; or, when 
 he defines it more accurately — " It is that 
 succession of related ideas and impressions, 
 of which we have an intimate memory and 
 consciousness.'' 
 
 I am, therefore, that succession of related 
 ideas and impressions of which I have the 
 intimate memory and consciousness. 
 
 But who is the / that has this memory 
 a!id consciousness of a succession of ideas 
 and impressions ? Why, it is nothing but 
 that succession itself. [583] 
 
 Hence, I learn, that this succession of 
 ideas and impressions intimately remembers, 
 and is conscious of itself. I would wish to 
 be farther instructed, whether the impres- 
 sions remember and are conscious of the 
 ideas, or the ideas remember and are con- 
 scious of the impressions, or if both remem- 
 ber and are conscious of both ? and whether 
 the ideas remember those that come after 
 them, as well as those that were before them ? 
 These are questions naturally arising from 
 thissystem, that have notyet been explained. 
 
 This, however, is clear, that this succes- 
 sion of ideas and impressions, not only re- 
 members and is conscious, but that it judges, 
 reasons, affirms, denies — nay, that it eats 
 and drinks, and is sometimes merry and 
 sometimes sad. 
 
 If these things can be ascribed to a suc- 
 cession of ideas and impressions, in»a con- 
 sistency with common sense, I should be 
 very glad to know what is nonsense. 
 
 The scholastic philosophers have been 
 wittily ridiculed, by representing them as 
 disputing upon ihis question — NumchimoBia 
 bombinans in vacuo possit comedere secun- 
 das intentionex 9 and I believe the wit of 
 man cannot invent a more ridiculous ques- 
 tion. But, if Mr Hume's philosophy be 
 admitted, this question deserves to be 
 treated more gravely : for if, as we learn 
 from this philosophy, a succession of ideas 
 and impressions may eat, and drink, and 
 be merry, I see no good reason why a 
 chimera, which, if not the same is of kin to 
 
 an idea, may not chew the cud upon that 
 kind of food which the schoolmen call second 
 intentions." 
 
 3. Another first principle I take to be — 
 That'lhosc tilings did redUifr happen which I 
 distinctly- remeTtiher. [584] 
 
 This has one of the surest marks of a first 
 principle ; for no man ever pretended to 
 prove it, and yet no man in his wits calls it 
 in question : the testimony of memory, like 
 that of consciousness, is immediate ; it 
 claims our assent upon its own authority.-}- 
 
 Suppose that a learned counsel, in defence 
 of a client against the concurring testimony 
 of witnesses of credit, should insist upon a 
 new topic to invalidate the testimony. 
 " Admitting," says he, " the integrity of 
 the witnesses, and that they distinctly re- 
 member what they have given in evidence- 
 it does not follow that the prisoner is guilty. 
 It has never been proved that the most 
 distinct memory may not be fallacious. 
 Shew me any necessary connection between 
 that act of the mind which we call memory, 
 and the past existence of the event remem- 
 bered. No man has ever offiered a shadow 
 of argument to prove such a connection ; 
 yet this is one link of the chain of proof 
 against the prisoner ; and, if it have no 
 strength, the whole proof falls to the ground : 
 until this, therefore, be made evident — until 
 it can be proved that we may safely rest 
 upon the testimony of memory for the truth 
 of past events — no judge or jury can justly 
 take away the life of a citizen upon so 
 doubtful a point." 
 
 I believe we may take it for granted, that 
 this argument from a learned counsel would 
 have no other effect upon the judge or jury, 
 than to convince them that he was dis- 
 ordered in his judgment. Counsel is allowed 
 to plead everything for a client that is fit to 
 persuade or to move ; yet I believe no 
 counsel ever had the boldness to plead this 
 topic. And for what reason ? For no other 
 reason, surely, but because it is absurd. 
 Now, what is absurd at the bar, is so in the 
 philosopher's chair. What would be ridi- 
 culous, if delivered to a jury of honest sen- 
 sible citizens, is no less so when delivered 
 gravely in a philosophical dissertation. 
 
 Mr Hume has not, as far as I remember, 
 directly called in question the testimony of 
 
 * All this criticism of lliime proreeds upon the 
 erroneous hypothesis that be was a Doffinalist. He 
 vviis a Sceptic— thai is, he accepted the principles as- 
 serted by the prevalent Dogmatism ; and only shewed 
 that such and such coi. elusions were, on these prin. 
 ciples, inevitable. Theabsurdity was not Hume's, but 
 Liicko's. 'I'his is the kind of criticism, however, 
 with which Hume is generally assailed. — H. 
 
 t The datum of Memory/ does not stand upon. the 
 same ground as the.daium of simple Consciousness. 
 In so far as memory- is consciousness, it cannot he 
 denied AVe cannot, without contradiction, deny the 
 fact of memory as a present consciousness ; but we 
 may, without contradiction, suppose that the past 
 given therein. Is only an illusion of the present.— H. 
 
 ["583, 584]
 
 CHAP, v.] FIRST PRINCIPLES OF CONTINGENT TRUTHS. 445 
 
 memory ; but he has laid down the premises 
 by which its authority is overturned, leav- 
 ing it to his reader to draw the conclu- 
 [585] 
 
 mg 
 siun. 
 
 He labours to shew that the belief or 
 assent which always attends the memory 
 and senses is nothing but the vivacity of 
 those perceptions which they present. He 
 shews very clearly, that this vivacity gives 
 no ground to believe the existence of ex- 
 ternal objects. And it is obvious that it 
 can give as little ground to believe the past 
 existence of the objects of memory. 
 
 Indeed the theory concerning ideas, so 
 generally received by philosophers, destroys 
 all the authority of memory, as well as the 
 authority of the senses. Des Cartes, Ma- 
 lebranche, and Locke, were aware that this 
 theory made it necessary for them to find 
 out arguments to prove the existence of ex- 
 ternal objects, which tlie vulgar believe 
 upon the bare authority of their senses ; 
 but those philosophers were not aware that 
 this theory made it equally necessary for 
 them to find arguments to prove the exist- 
 ence of things past, which we remember, 
 and to support the authority of memory. 
 
 All the arguments they advanced to sup- 
 port the authority of our senses, were easily 
 refuted by Bishop Berkeley and Mr Hume, 
 being indeed'very weak and inconclusive. 
 And it would have been as. easy to answer 
 every argument they could have brought, 
 consistent with their theory, to support the 
 authority of memory. 
 
 For, according to that theory, the im- 
 mediate object of memory, as well as of 
 every other operation of the understanding, 
 is an idea present in the mind. And, from 
 the present existence of this idea of me- 
 mory I am left to infer, by reasoning, that, 
 six months or six years ago, there did ex- 
 ist an object similar to. this idea. [58G] 
 
 But what is there in the idea that can 
 lead me to this conclusion ? What mark 
 does it bear of the date of its archetype ? 
 Or what evidence have I that it had an 
 archetype, and that it is not the first of its 
 kind ? 
 
 Berhaps it will be said, that this idea or 
 image in the mind must have had a cause. 
 
 1 admit that, if there is such an image in 
 the mind, it must have had a cause, and a 
 cause able to produce the effect ;.but what 
 can we infer from its having a cause ? Does 
 it follow that tlie effect is a type, an image, 
 a copy of its cause ? Then it will follow, 
 that a picture is an image of the painter, 
 and a coach of tlie coachmaker. 
 
 A i)ast event may be known by reasoning; 
 but that is not remembering it. When I 
 remember a thing distinctly, I disdain 
 equally to hear reasons for it or against it. 
 And 80 I think does every roan in his 
 senses. 
 [^58.5-587 ] 
 
 4. Another first principle is, Our own per- \ 
 sonal ideniiry and cimlinucd exhtrnce, as 
 far back as we remember atiylhing disthictly. 
 
 This we know immediately, and not 
 by reasonmg. It seems, indeed, to be a 
 part of the testimony of memory. Every- 
 thing we remember has such a relation to 
 ourselves as to imply necessarily our ex- 
 istence at the time remembered. And 
 there cannot be a more palpable absurdity 
 than that a man should remember what 
 happened before he existed. He must 
 therefore have existed as far back as he re- 
 members anything distinctly, if his memory 
 be not fallacious. This principle, there- 
 fore, is so connected with the last mention- 
 ed, that it may be doubtful whether both 
 ought not to be included in one. Let 
 ev^ry one judge of this as hc'sees reason. 
 The proper notion of identity, and the sen- 
 timents of Mr Locke on this subject, have 
 been considered before, under the head of 
 Memory. [587] 
 
 5. Another first principl^ is, That those j 
 thini/s do really e.rist which we distinctly I 
 perceive by our senses, and aie what we ' 
 perceive them to le. 
 
 It is too evident to need proof, that all 
 men are by nature led to give implicit faith 
 to the distinct testimony of their senses, 
 long before they are capable of any bias 
 from prejudices of education or of philo- 
 sophy. 
 
 How came we at first to know that there 
 are certain beings about us whom we call 
 father, and mother, and sisters, and bro- 
 thers, and nurse ? Was it not by the 
 testimony of our senses ? How did these 
 persons convey to us any information or 
 instruction ? Was it not by means of our 
 senses ? 
 
 It is evident we can have no communi- 
 cation, no correspondence or society with 
 any created being, but by means of our 
 senses. And, until we rely upon their testi- 
 mony, we nmst consider ourselves as being 
 alone m the universe, without any fellow- 
 creature, living or inanimate, and be left to 
 converse with our own thoughts. 
 
 Biahop Berkeley surely did not duly con- 
 sider that it is by means of the material 
 world that we have any correspondence 
 with thinking beings, or any knowledge of 
 their existence ; and that, by depriving us 
 of the material world, he deprived us, at 
 the same time, of family, friends, country, 
 and every human creature ; of every object 
 of affection, esteem, or concern, except our- 
 selves. 
 
 Tlu! good Bishop surely never intended 
 this. He was too warm a friend, too -zeal- 
 ous a patriot, and too giKid a Cliristian, to 
 be capable of such a thought. He was not 
 aware of the consequences of his system, 
 and therefore theyouglit not to be imputed
 
 446 
 
 ON THE INTELLECTUAL POWERS. 
 
 ^ESSAY VI. 
 
 to him ; but we must impute them to the 
 system itself. It stifles every generous and 
 social principle. [588] 
 
 When I consider myself as speaking to 
 men who hear me, and can judge of what 
 I say, I feel that respect which is due to 
 such an audience. I feel an enjoyment in 
 a reciprocal communication of sentiments 
 with candid and ingenious friends ; and my 
 soul blesses the Author of my being, who 
 has made me capable of this manly and 
 rational entertainment. 
 
 But the Bishop shews me, that this is 
 all a dream ; that I see not a human face ; 
 that all the objects I see, and hear, and 
 handle, are only the ideas of my own mind ; 
 ideas are my only companions. Cold com- 
 pany, indeed ! Every social affection freezes 
 at the thought ! 
 
 But, my Lord Bishop, are there no minds 
 left in the universe but my own ? 
 
 Yes, indeed ; it is only the material 
 world that is annihilated ; everything else 
 remains as it was. 
 
 This seems to promise some comfort in 
 my forlorn solitude. But do I see those 
 minds ? No. Do I see their ideas ? No. 
 Nor do they see me or my ideas. They 
 are, then, no more to me than the inhabit- 
 ants of Solomon's isles, or of the moon ; 
 and my melancholy solitude returns. Every 
 social tie is broken, and every social affec- 
 tion is stifled. 
 
 This dismal system, which, if it could be 
 believed, would deprive men of every social 
 comfort, a very good Bishop, by strict and 
 accurate reasoning, deduced from the prin- 
 ciples commonly received by philosophers 
 concerning ideas. The fault is not in the 
 reasoning, but in the principles from which 
 it is drawn. 
 
 All the arguments urged by Berkeley and 
 Hume, atjainst the existence of a material 
 world, are grounded upon this prnieiple — 
 that we do not perceive external objects 
 themselves, but certain images or ideas in 
 our own minds.* But this is no dictate of 
 common sense, but directly contrary to the 
 Bense of all who have not been taught it by 
 philosophy. [589] 
 
 We have before examined the reasons 
 given by philosophers to prove that ideas, 
 and not external objects, are the immediate 
 objects of perception, and the instances 
 given to prove the senses fallacious. With- 
 out repeating what has before been said 
 upon those points, we shall only here ob- 
 serve, that, if external objects be perceived 
 immediately, we have the same reason to 
 
 * Idealism, as' already nnficed, rests equally well, 
 if not belter, on the hypothesis that what we perceive 
 (or are conscious of in (lerception) is only a modifica- 
 tion of miml, as on the hypothesis that, in perception, 
 we are conscious of a representative entity distinct 
 from mind as from the external reality.— H. 
 
 believe their existence as philosophers have 
 to believe the existence of ideas, while they 
 hold them to be the immediate objects of 
 perception.* 
 
 G. Another first principle, I think, is, 
 Thnl we have some degree of power over 
 our actions, and the determinations of our 
 will. 
 
 All power must be derived from the 
 fountain of power, and of every good gift. 
 Upon His good pleasure its continuance de- 
 pends, and it is always subject to his con- 
 trol. 
 
 Beings to whom God has given any de- 
 gree of power, and understanding to direct 
 them to the proper use of it, must be ac- 
 countable to their Maker. But those who 
 are intrusted with no power can have no 
 account to make ; for all good conduct con- 
 sists in the right use of power ; all bad 
 conduct in the abuse of it. 
 
 To call to account a being who never was 
 intrusted with any degree of power, is an 
 absurdity no less than it would be to call 
 to account an inanimate being. We are 
 sure, therefore, if we have any account to 
 make to the Author of our being, that we 
 must have some degree of power, which, 
 as far as it is properly used, entitles us to 
 his approbation ; and, when abused, renders 
 us obnoxious to his displeasure. [590] 
 
 It is not easy to say in what way we first 
 get the notion or idea of power. It is 
 neither an object of sense nor of conscious- 
 ness. We see events, one succeeding an- 
 other ; but we see not the power by which 
 they are produced. We are conscious of 
 the operations of our minds ; but power is 
 not an operation of mind. If we had no 
 notions but such as are furnished by the 
 external senses, and by consciousness, it 
 seems to be impossible that we should ever 
 have any conception of power. Accord- 
 ingly, Mr Hume, who has reasoned the 
 most accurately upon this hypothesis, denies 
 that we have any idea of power, and clearly 
 refutes the account given by Mr Locke of 
 the origin of this idea. 
 
 But it is in vain to reason from a hypo- 
 thesis against a fact, the truth of which 
 every man may see by attending to his own 
 thoughts. It is evident that all men, very 
 early in life, not only have an idea of power, 
 but a conviction that they have some de- 
 gree of it in themselves ; for this conviction 
 is necessarily implied in many operations 
 of mind, which are familiar to every man, 
 and without which no man can act the part 
 of a reasonable being. 
 
 First, It is implied in every act of voli- 
 tion. " Volition, it is plain," says Mr 
 Locke, " is an act of the mind, knowingly 
 
 * Philosophers admitted that we are conscious of 
 these ; does Reid admit this of external objects ? — H. 
 
 [588-690]
 
 CHAP, v.] FIRST PRINXIPLES OF COxNTlNGENT TRUTHS. 
 
 447 
 
 exerting that dominion which it takes itself 
 to liave over any part of the man, by em- 
 ploying it in, or withholding it from any 
 particular action." Every volition, there- 
 fore, implies a conviction of power to do the 
 action willed. A man may desire to make 
 a visit to the moon, or to the planet Jupi- 
 ter ; but nothing but insanity could make 
 him will to do so. And, if even insanity 
 produced this effect, it umst be by making 
 him think it to be in his power. 
 
 Secondly, This- conviction is implied in 
 all deliberation ; for no man in his wits de- 
 liberates whether he shall do what he be- 
 lieves not to be in his power. Tiurdlij, 
 The same conviction is implied in every 
 resolution or purpose formed in consequence 
 of deliberation. A man may as well form 
 a resolution to pull the moon out of her 
 sphere, as to do the most insignificant action 
 which he believes not to be in his power. 
 The same thing may be said of every pro- 
 raise or contract wherein a man plights his 
 faith ; for he is not an honest man who 
 promises what he does not believe he has 
 power to perform. [591] 
 
 As these operations imply a belief of 
 some degree of power in ourselves ; so there 
 are others equally common and familiar, 
 which implv a like belief with regard to 
 others. 
 
 When we impute to a man any action or 
 omission, as a ground of approbation or of 
 blame, we must believe he had power to do 
 otherwise. The same is implied in all 
 advice, exhortation, command, and rebuke, 
 and in every case in which we rely upon his 
 fidelity in performing any engagement or 
 executing any trust. 
 
 It is not more evident that mankind have 
 a conviction of the exis ence of a material 
 world, than that they have the conviction 
 of some degree of power in themselves and 
 in others ; every one over his own actions, 
 and the determinations of his will — a con- 
 viction so early, so general, and so inter- i 
 woven with the whole of human conduct, 
 that it nni-t be the natural effect of our 
 constitution, and intended by the Author of 
 our being to guide our actions. 
 
 It resembles our conviction of the ex- 
 istence of a material world in this respect 
 also, that even tiiose who reject it in specu- 
 lation, find themselves under a necessity of 
 being governed by it in their practice ; and 
 thus it will always happen when philosophy 
 contradicts first |)rinciple&. 
 
 7- Another first principle is — Thiil the 
 ^ ! natural fin-ulties, by which we (lisliniiuish 
 truth from error, are not fallncions. Ifanv 
 man should demand a proof of this, it is 
 impossible to satisfy him. Tor, sujiposc it 
 should be inathen)atically demonslr.itcd, 
 this would signify nothing in this case; 
 because, to judge of a demonstration, a man 
 [591-593] 
 
 must trust his faculties, and take for granted 
 the very thing in question. [592] 
 
 If a man's honesty were called in ques- 
 tion, it would be ridiculous to refer it to the 
 man's own word, whether he be honest or 
 not. The same absurdity there is in at- 
 tempting to prove, by any kind of reasoning, 
 probable or demonstrative, that our reason 
 is not fallacious, since the very point in 
 question is, whether reasoning may be 
 trusted. 
 
 If a sceptic should build his scepticism 
 upon this foundation, that all our reasoning 
 and judging powere are fallacious in their 
 nature, or should resolve at least to with- 
 hold assent until it be proved that they are 
 not, it would be impossible by argument 
 to beat him out of this stronghold ; and he 
 must even be left to enjoy his scepticism. 
 
 Des Cartes certainly made a false step in 
 this matter, for having suggested this doubt 
 among others — that whatever evidence he 
 might have from his consciousness, his 
 senses, his memory, or his reason, yet 
 possibly some malignant being had given 
 him those faculties on purpose to impose 
 upon him ; and, therefore, that they are not 
 to be trusted without a proper voucher. 
 To remove this doubt, he endeavours to 
 prove the being of a Deity who is no de- 
 ceiver; wlience he concludes, that the facul- 
 ties he had given him are true and worthy 
 to be trusted. 
 
 It is strange that so acute a re.asoner did 
 not perceive that in this reasoning there is 
 evidently a begging of the question. 
 
 For, if our faculties be fallacious, why 
 may they not deceive us in this reasoning as 
 well as in others ? And, if they are not to 
 be trusted in this instance without a voucher, 
 why not in others ? [593] 
 
 Every kind of reasoning for the veracity 
 of our faculties, amounts to no more than 
 taking their own testimony for their vera- 
 city ; and this we must do implicitly, until 
 God give us new faculties to sit in judg- 
 ment upon the old ; and the reason why 
 Des Cartes satisfied himself with so weak 
 an argument for the truth of his faculties, 
 most probably was, that he never seriously 
 doubted of it. 
 
 If any truth can be said to be prior to all 
 others in the order of nature, this seems 
 to have the best claim.; because, in every 
 instance of assent, whether upon intuitive, 
 demonstrative, or probable evidence, the 
 truth of our faculties is taken for granted, 
 and is, as it were, one of the premises on i 
 which our assent is grounded.* 
 
 How then come we to be assured of this 
 
 * 'I'luTC is a prcsympiion in favour ol ihc voracity 
 nf the prim.Afy <lata olc()iis(iou»tio«s. I hu can only 
 Iw rtbutti'il l)v sliewmnlli.i; tlicsc lads arc ciintrfiilic. 
 tfiry. Si cpticitni ali<iii|)ls to sliew this on Ihc priiu 
 cipJcH which Oii({ir.ati>-in jMiKtiilatcB. — II. 

 
 448 
 
 ON THE INTELLECTUAL POVV^ERS. 
 
 [_ESSAV VI. 
 
 fundamental truth on which all others rest ? 
 Perhaps evidence, as in many other respects 
 it resembles light, so in this also — that, as 
 iij^ht, which is the discoverer of all visible 
 objects, discovers itself at the same time, 
 80 evidence, which is the voucher for all 
 truth, vouches for itself at the same time. 
 
 This, liowever, is certain, that such is 
 the constitution of the human mind, that 
 evidence discerned by us, forces a corre- 
 sponding degree of assent. And a man 
 who perfectly understood a just syllogism, 
 without believing that the conclusion follows 
 from the premises, would be a greater mon- 
 ster than a man born without hands or 
 feet. 
 
 We are born under a necessity of trust • 
 ing to our reasoning and judging powers ; 
 an^ a real belief of their being fallacious 
 cannot be maintained for any considerable 
 time by the greatest sceptic, because it is 
 doing violence to our constitution. It is 
 like a man's walking upon his hands, a feat 
 which some men upon occasion can exhibit ; 
 but no man ever made a long journey in 
 this manner. Cease to admire his dexte- 
 rity, and he will, like other men, betake 
 himself to his legs. [59-1 ] 
 
 We may here take notice of a property 
 of the principle under consideration, that 
 seems to be common to it with many other 
 first principles, and which can hardly be 
 found in any princii)le that is built solely 
 upon reasoning ; and that is, that in most 
 men it produces its effect without ever being 
 attended to, or made an object of thought. 
 No man ever thinks of this principle, unless 
 when he considers the grounds of scepticism; 
 yet it invariably governs his opinions. 
 When a man in the common course of 
 life gives credit to the testimony of his 
 senses, his memory, or his reason, he does 
 not put the question to himself, whether 
 these faculties may deceive him ; yet the 
 trust he reposes in them supposesan inward 
 conviction, that, in that instance at least, 
 they do not deceive him. 
 
 It is another property of this and of many 
 first principles, that they force assent in par- 
 ticular instances, more powerfully than 
 when they are turned into a general propo- 
 sition. Many sceptics have denied every 
 general principle of science, excepting per- 
 haps the existence of our present thoughts ; 
 yet these men reason, and refute, and prove, 
 they assent and dissent in particular cases. 
 They use reasoning to overturn all reason- 
 ing, and judge that they ought to have no 
 judgment, and see clearly that they are 
 Wind. Many have in general maintained 
 that the senses are fallacious, yet there 
 never was found a man so sceptical as not 
 to trust his senses in particular instances 
 when his safety required it ; and it may be 
 observed of those who have professed scep- 
 
 ticism, that their scepticism lies in generals, 
 while in particulars they are no less dog- 
 matical than others. 
 
 8. Another first principle relating to ex- > 
 istence, is. That there is.lifo and intelligence \ 
 in our. fellow-men with whoimve converse. \ 
 
 As soon as children are capable of asking ' 
 a question, or of answering a question, as 
 soon as they shew the signs of love, of re- 
 sentment, or of any other affection, they 
 must be convinced that those with whom 
 tliey have this intercourse are intelligent 
 beings. [505] 
 
 It is evident they are capable of such in- 
 tercourse lo^ig before they can reason. 
 Every one knows that there is a social in- 
 tercourse between the nurse and the child 
 before it is a year old. It can, at that age, 
 understand many things that are said to it. 
 
 It can by signs ask and refuse, threaten 
 and supplicate. It clings to its nurse in 
 danger, enters into her grief and joy, is hap- 
 py in her soothing and caresses, and un- 
 happy in her displeasure. That these 
 things cannot be without a conviction in 
 the child that the nurse is an intelligent 
 being, I think must be granted- 
 
 Now. I would ask how a child of a year 
 old comes by this conviction ? Not by rea- 
 soning surely, for children do not reason at 
 that age. Nor is it by external senses, fo; 
 life and intelligence are not objects of the 
 external senses. 
 
 By what means, or upon what occasions, 
 Nature first gives this information to the 
 infant mind is not easy to determine. We 
 are not capable of reflecting upon our own 
 thoughts at that period of life ; and before 
 we attain this capacity, we have quite for- 
 got how or on what occasion we tirat had 
 tills belief ; we perceive it in those who are 
 born blind, and in others who are born 
 deaf; and therefore Nature has not con- 
 nected it solely either with any object of 
 sight, or with any object of hearing. When 
 we grow up to the years of reason and re- 
 flection, this belief remains. No man thinks 
 of asking himself what reason he has to be- 
 lieve that his neighbour is a living creature. 
 He would be not a little surprised if another 
 person should ask him so absurd a ques- 
 tion ; and perhaps could not give any rea- 
 son which would not equally prove a watch 
 or a puppet to be a living creature. 
 
 But, though you should satisfy him of the 
 weakness of the reasons he gives for his be- 
 lief, you cannot make him in the least 
 doubtful. This belief stands upon another 
 foundation than that of reasoning ; and 
 therefore, whether a man can give good 
 reasons for it or not, it is not in his power 
 to shake it off. [596] 
 
 Setting aside this natural conviction, I 
 believe the best reason we can give, to 
 prove that other men are living and mtelli- 
 
 [594-596]
 
 OBAP. v.] FIRST PRINCIPLES OF C0NTIXGP:NT TRUTHS 449 
 
 gent, is, that their words and actions indi- 
 cate like powers of understanding as we 
 are conscious of in ourselves. The very 
 same argument applied to the woi-ks of na- 
 ture, leads us to conclude that there is an 
 intelligent Author of nature, and appears 
 equally strong and obvious in the last case 
 as in the first ; so that it may be doubted 
 whether men, by the mere exercise of rea- 
 soning, might not as soon discover the ex- 
 istence of a Deity, as that other men have 
 life and intelligence. 
 
 The knowledge of the last is absolutely 
 necessary to our receiving any improve- 
 ment by means of instruction and example ; 
 and, without these means of improvement, 
 there is no ground to tiiink that we should 
 ever be able to acquire the use of our rea- 
 soning powers. This knowledge, therefore, 
 must be antecedent to reasoning, and there- 
 fore must be a first principle. 
 
 It cannot be said that tiie judgments we 
 form concerning life and intelligence in 
 other beings are at first free from error. 
 But the errors of children in this matter 
 lie on the safe side ; they are prone to at- 
 tribute intelligence to things inanimate. 
 These errors are if small consequence, and 
 are gradually corrected by experience and 
 ripe judgment. But the belief of life and 
 intelligence in other men, is absolutely ne- 
 cessary for us before we are capable of 
 reasoning ; and therefore the Author of 
 our being hath given us this belief antece- 
 dently to all reasoning. 
 
 9. Another first principle I take to be, 
 Thai certain features of the countenance, 
 sounds of the voice, and gestures (f the body, 
 indicate certain thoughts and dispositions (f 
 mind. [597] 
 
 That many operations of the mind have 
 their natural signs in the countenance, voice, 
 and gesture, I suppose every man will ad- 
 mit. Omnis enim moins unimi, says Cicero, 
 huum qnemdam huhel a nalnni, vu/tum, el 
 vooem el gestum. The only question is, 
 whether we understand the signilication of 
 those signs, by the constitution of our na- 
 ture, by a kiml of natural perception !-imi- 
 lar to the perce])tions of sense ; or whether 
 we gradually karu the signification of such 
 signs from experience, as we learn tliat 
 smoke is a sign of fire, or that the freezing 
 of water is a sign of cold ? I take the first 
 to be the truth. 
 
 It seems to me incredible, that the no- 
 tions men have of the expression of features, 
 voice, and gesture, are entirely the fruit of 
 experience. Children, almost assoon as born, 
 may be frighted, ami thrown into fits l)y a 
 threatening or angry tone of voice. I knew 
 a man who could make an infant cry, by 
 whistling a nichinelioly tune in the same; 
 or in the next room ; ami again, Ijy alter- 
 ing his kev, and the strain of liis music, 
 [597, 598] 
 
 could make the child leap and dance for 
 
 It is not by experience surely that we 
 learn the expression of music ; for its opera- 
 tion is commonly strongest the first time we 
 hear it. One air expresses mirth and festi- 
 vity—so that, when we hear it, it is with 
 difficulty we can forbear to dance ; another 
 is sorrowful and solemn. One inspires with 
 tenderness and love ; another with rage and 
 fury. 
 
 " Hear how Timotheus varied lays surprise. 
 And bid alternate passions fall and rise ; 
 While at eacli change, tne son of I,\biaii Jove 
 Now burns with glory, and then melts with love. 
 Now his tierce eyes with spiirklinii fury glow, 
 Now sighs steaKout, and tears begm to Sow. 
 Persians and Greeks, like turns of Nature, found, 
 A lid the world's victor stood sul du'd by sound." 
 
 It is not necessary that a man have studied 
 either music or the passions, in order to his 
 feeling these eftects. The most ignorant 
 and unimproved, to whom Nature has given 
 a good ear, feel them as strongly as the 
 most knowing. [698] 
 
 The countenance and gesture have an 
 expression no less strong and natural than 
 the voice. The first time one sees a stern 
 and fierce look, a contracted brow, and a 
 menacing posture, he concludes that the 
 person is infiained with anger. Shall we 
 say, that, previous to experience, the most 
 hostile countenance has as agreeable an 
 appearance as the most gentle and benign ? 
 This surely would contradict all experience ; 
 for we know that an angry countenance 
 will fright a child in the cradle. Who has 
 not observed that children, very early, are 
 able to distinguish what is said to them in 
 jest from what is said in earnest, by the 
 tone of the voice, and the features of the 
 face ? They judge by these natural signs, 
 even when they seem to contradict the arti- 
 ficial. 
 
 If it were by experience that we learn 
 the meaning of features, and sound, and 
 gesture, it might be expected that we should 
 recollect the time when we first learned 
 those lessons, or, at least, some of such a 
 multitude. 
 
 Those who give attention to the opera- 
 tions of children, can easily discover the 
 time when they have their earliest notices 
 from experience— such as that Hamc will 
 burn, or that kniv(\s will cut. But no 
 man is able to recollect in himself, or to 
 observe in others, the time when the espn s- 
 sion of the face, voice, and gesture, wcro 
 learned. 
 
 Nay, I apprehend that it is impossible * 
 that this should be learned from experi- 
 ence. 
 
 When we sec the siu'U, and see the tiling 
 signified always conjoined with it, expe- 
 rience! may be tlio iiistniclor, ami teach us 
 how that sign is to be interjirelcd. But 
 
 '2 <)
 
 450 
 
 ON THE INTELLECTUAL POWERS. 
 
 [|eS3AY VI. 
 
 how shall experience instruct us when we 
 see the sign only, when the thing signified 
 is invisible ? Now, this is the ease here : 
 the thoughts and passions of the mind, as 
 well as the mind itself, are invisible, and 
 therefore their connection with any sensible 
 sign cannot be first discovered by expe- 
 perience ; there must be some earlier source 
 of this knowledge. [599] 
 
 Nature seems to have given to men a 
 faculty or sense, by which this connection 
 is perceived. And the operation of this 
 sense is very analogous to that of the ex- 
 ternal senses. 
 
 When I grasp an ivory ball in my hand, 
 I feel a certain sensation of touch. In the 
 sensation there is nothing external, nothing 
 corporeal. The sensation is neither round 
 nor hard ; it is an act of feeling of the 
 mind, from which I cannot, by reasoning, 
 infer the existence of any body. But, by 
 the constitution of my nature, the sensation 
 carries along with it the conception and be- 
 lief of a round hard body really existing in 
 my hand. 
 
 In like manner, when I see the features 
 of an expressive face, I see only figure and 
 colour variously modified. But, by the 
 constitution of my nature, the visible ob- 
 ject brings along with it the conception 
 and belief of a certain passion or sentiment 
 in the mind of the person. 
 
 In the former case, a sensation of touch 
 is the sign, and the hardness and roundness 
 of the body I grasp is signified by that sen- 
 sation. In the latter case, the features of 
 the person is the sign, and the passion or 
 sentiment is signified by it. 
 
 The power of natural signs, to signify 
 the sentiments and passions of the mind, is 
 seen in the signs of dumb persons, who can 
 make themselves to be understood in a con- 
 siderable degree, even by those who are 
 wholly inexperienced in that language. 
 
 It is seen in the traffic which has been fre- 
 quently carried on between people that have 
 no common acquired language. They can 
 buy and sell, and ask and refuse, and shew a 
 friendly or hostile disposition by natural 
 signs. [600] 
 
 It was seen still more in the actors 
 among the ancients who performed the 
 gesticulation upon the stage, while others 
 recited the words. To such a pitch was 
 this art carried, that we are told Cicero 
 and Roscius used to contend whether the 
 orator could express anything by words, 
 which the actor could not express in dumb 
 show by gesticulation ; and whether the 
 same sentence or thought could not be act- 
 ed in all the variety of ways in which the 
 orator could express it in words. 
 
 But the most surprising exhibition of 
 this kind, was that of the pantomimes 
 among the Romans, who acted plays, or 
 
 scenes of plays, without any recitation, and 
 yet could be perfectly understood. 
 
 And here it deserves our notice, that, al- 
 though it required much study and practice 
 in the pantomimes to excel in their art, 
 yet it required neither study nor practice in 
 the spectators to understand them. It was 
 a natural language, and therefore under- 
 stood by all men, whether Romans, Greeks, 
 or barbarians, by the learned and the un- 
 learned. 
 
 Lucian relates, that a king, whose domi- 
 nions bordered upon the Euxine Sea, hap- 
 pening to be at Rome in the reign of Nero, 
 and having seen a pantomime act, begged 
 him of Nero, that he might use him in his 
 intercourse v\ith all the nations in his 
 neighbourhood ; for, said he, I am obliged 
 to employ I don't know how many inter- 
 preters, in order to keep a correspondence 
 with neighbours who speak many languages, 
 and do not understand mine ; but this fel- 
 low will make them all understand him. 
 
 For these reasons, I conceive, it must be 
 granted, not only that there is a connection 
 established by Nature between certain signs 
 in the countenance, voice, and gesture, and 
 the thoughts and passions of the mind ; but 
 also, that, by our constitution, we under- 
 stand the meaning of those signs, and from 
 the sign conclude the existence of the thing 
 signified, [GOl] 
 
 10. Another first principle appears to 
 me to be — That there is a certain repard 
 due to hvman lestimoy^y in matters of fact, 
 and even to human aulhorify in matters of 
 opinion. 
 
 Before we are capable of reasoning about 
 testimony or authority, there are many 
 things which it concerns us to know, for 
 which we can have no other evidence. The 
 wise Author of nature hath planted in the 
 human mind a propensity to rely upon this 
 evidence before we can give a reason for 
 doing so. This, indeed, puts our judgment 
 almost entirely in the power of those who 
 are about us in the first period of Hie ; but 
 this is necessary both to our preservation 
 and to our improvement. If children were 
 so framed as to pay no regard to testimony 
 or to authority, they must, in the literal 
 sense, perish for lack of knowledge. It is 
 not more necessary that they should be fed 
 before they can feed themselves, than that 
 they should be instructed in many things 
 before they can discover them by their own 
 judgment. 
 
 But, when our faculties ripen, we find 
 reason to check that propensity to yield to 
 testimony and to authority, which was so 
 necessary and so natural in the first period 
 of life. We learn to reason about the re- 
 gard due to them, and see it to be a childish 
 weakness to lay more stress upon them than 
 than reason justifies. Yet, I believe, to 
 
 [399-601"!
 
 CHAP, v.] FIRST PRINCIPLES OF CONTLXGENT TRUTHS. 451 
 
 the end of life, most men are more apt to |^o 
 into this extreme tlian into the contrary ; 
 and the natural propensity still retains some 
 force. 
 
 The natural principles, by which our 
 judgments and opinions are regulated before 
 we come to the use of reason, seem to be no 
 less necessary to such a being as man, than 
 those natural instincts which the Author of 
 nature hath given us to regulate our actions 
 during that period. [002] 
 
 11. There are manij events depending 
 up"u the will of man, in which there is a 
 Self-evident probaUlitt/, greater or lesx, ac- 
 cording to circumstances. 
 
 There may be in some individuals such a 
 degree of frenzy and madness, that no 
 man can say what they may or may not do. 
 Such persons we find it necessary to put 
 under restraint, that as far as possible they 
 may be kept from doing harm to themselves 
 or to others. They are not considered as 
 reasonable creatures, or members of society. 
 But, as to men who have a sound mind, we 
 depend upon a certain degree of regularity 
 in their conduct ; and could put a thousand 
 different cases, wherein we could venture, 
 ten to one, that they will act in such a way, 
 and not in the co:itrary. 
 
 If we had no confidence in our fellow-men 
 that they will act such a part in such cir- 
 cumstances, it would be impossible to live 
 in society with them. For that which 
 makes men capable of living in society, and 
 uniting in a political body under government, 
 is, tliat their actions will always be regu- 
 lated, in a great measure, by the common 
 principles of human nature. 
 
 It may always be expected that they 
 will regard their own interest and reputa- 
 tion, and that of their families and friends ; 
 that they will repel injuries, and have some 
 sense of good offices ; and that they will 
 have some regard to truth and justice, so 
 far at least as not to swerve from them 
 without temptation. 
 
 It is upon such principles as these, that 
 all political reasoning is grounded. Such 
 reasoning is never demonstrative ; but it 
 may have a very great degree of probability, 
 especially when applied to great bodies of 
 men. [GO.-J] 
 
 12. The last principle of contingent truths 
 I mention is, That, in the pheeiomcnrt of 
 niture, what i.v to be, will probably be like 
 to what has been in similar circumslanres.* 
 
 We must have this conviction as soon as 
 we are capable of learning anything from 
 evperience ; for all cx])eriencc is grounded 
 upon a belief that the future will be like 
 the past. Take away this i)rinciple, and 
 the experience of an hundred years makes 
 
 * Compare above, " Inquiry," c. vi. 5 '<?+• Btewart's 
 " Elemeiitu", i. p. i;05. " Philojophical Essays," 
 p. 74, K\. — H. 
 
 us no wiser with regard to what is to 
 come. 
 
 This is one of those principles which, 
 when we grow up and observe the course of 
 nature, we can confirm by reasoning. We 
 j)erceive that Nature is governed by fixed 
 laws, and that, if it were not so, there could 
 be no such thing as prudence in human 
 Conduct ; there would be no fitness in any 
 means to promote an end ; and what, on 
 one occasion, promoted it, might as pro- 
 bably, on another occasion, obstruct it. 
 
 But the principle is necessary for us be- 
 fore we are able to discover it by reasoning, 
 and therefore is made a part of our consti- 
 tution, and produces its effects before the 
 use of reason. 
 
 This principle remains in all its force 
 when we come to the use of reason ; but 
 we learn to be more cautious in the appli- 
 cation of it. We observe more carefully 
 the circumstances on which the past event 
 depended, and learn to distinguish them 
 from those which were accidentally con- 
 joined with it. 
 
 In order to this, a number of experi- 
 ments, varied in their circumstances, is 
 often necessary. Sometimes a single ex- 
 periment is thought sufficient to establish a 
 general conclusion. Thus, when it was 
 once found, that, in a certain degree of cold, 
 quicksilver became a hard and malleable 
 metal, there was good reason to think that 
 the same degree of cold will always produce 
 this effect to the end of the world. [604] 
 
 I need hardly mention, that the whole 
 fabric of natural philosophy is built upon 
 this principle, and, if it be taken away, 
 must tumble down to the foundation. 
 
 Therefore the great Newton lays it down 
 as an axiom, or as one of his laws of philo- 
 sophising, in these words, Effectuum natur- 
 alnan ejusdem generis easdem esse causas. 
 This is what every man assents to, as soon 
 as he understands it, and no man asks a 
 reason for it. It has, therefore, the most 
 geuuiue marks of a first principle. 
 
 It is very remarkable, that, although all 
 our expectation of what is to happen in the 
 course of nature is derived from the belief 
 of this princi|)lc, yet no man thinks of ask- 
 ing what is the ground of this belief. 
 
 JNIr Hume, I think, was the fiist* who 
 put this question ; and he has shown clearly 
 and invincibly, that it is neither grounded 
 upon reasoning, nor has that kind of intui- 
 tive evidence which mathematical axioms 
 have. It is not a necessary truth. 
 
 He has endeavoured to account f(jr it 
 upon his own principles. It is not my 
 business, at prcsont, to examine the account 
 he has given of this universal belief of man- 
 
 * Hume was not tlio Writ: l)iil on the varioin 
 opinions touchiriK the ground of itiin expectancy, I 
 raimot touch.— H. 
 
 '2 u U
 
 452 
 
 ON THE INTELLECTUAL POVV^EHS. 
 
 [[essay vr. 
 
 kind ; because, whether his account of it be 
 just or not, (and I think it is not,) yet, as 
 this belief is universal among mankind, and 
 is not grounded upon any antecedent rea- 
 soning, but upon the constitution of the 
 mind itself, it must be acknowledged to be 
 a first principle, in the sense in which I 
 use that word. 
 
 I do not at all affirm, that those I have 
 mentioned are all the first principles from 
 which we may reason concerning contingent 
 truths. Such enumerations, even when 
 made after much reflection, are seldom per- 
 fect. [605] 
 
 CHAPTER VI. 
 
 FIRST PRINCIPLES OF NECESSARY TRUTHS. 
 
 About most of the first principles of ne- 
 cessary truths there has been no dispute, 
 and therefore it is the less necessary to 
 dwell upon them. It will be suflicient to 
 divide them into different classes ; to men- 
 tion some, by way of specimen, in each 
 class ; and to make some remarks on those 
 of which the truth has been called in ques- 
 tion. 
 
 They may, I think, most properly be 
 divided according to the sciences to which 
 they belong. 
 
 1. There are some first principles that 
 may be called grammatical , such as, T/iat 
 every adjective in a sentence must belong to 
 some substantive expressed or understnod ; 
 That every complete sentence must have a 
 verb. 
 
 Those who have attended to the struc- 
 ture of language, and formed distinct no- 
 tions of the nature and use of the various 
 parts of speech, perceive, without reasoning, 
 that these, and many other such principles, 
 are necessarily true. 
 
 2. There are logical axioms : such as, 
 That (1111/ contexture of uvtrds which dues not 
 make a proposition , is neither true nor false ; 
 That' even/ prnposilion is either true or 
 
 false ; That no proposition can be both true 
 and false at the same time ; That reasoning 
 in a circle proves nothing ; That whatever 
 may be Iruli/ affirmed of a geitu^, may be 
 truly affirmed of all the species, and all the 
 individuals Jjelonging to that genus. [606] 
 
 3. Every one knows there are malhemalical 
 axioms.* Mathematicians have, from the 
 days of Euclid, very wisely laid down the 
 axioms or first principles on which they 
 reason. And the eff'ect which this appears 
 to have had upon the stability and hup]>y 
 progress of this science, gives no small en- 
 couragement to attempt to lay the founda- 
 tion of other sciences in a similar manner, 
 as far as we are able. 
 
 * See Stewart's " Elements," ii. p. 3S, sq. — H. 
 
 Mr Hume hath discovered, as he appre- 
 hends, a weak side, even in mathematical 
 axioms ;• and thinks that it is not strictly 
 true, for instance, that two right lines can 
 cut one another in one point only. 
 
 The principle he reasons from is, That 
 every simple idea is a copy of a preceding 
 impression ; and therefore in its precision 
 and accuracy, can never go beyond its ori- 
 ginal. From which he reasons in this man- 
 ner : No man ever saw or felt a line so 
 straight that it might not cut anotlier, 
 equally straight, in two or more points. 
 Therefore, there can be no idea of such a 
 line. 
 
 The ideas that are most essential to geo- 
 metry — such as those of equality, of a 
 straight line, and of a square surface, are far, 
 he says, from being distinct and deter- 
 minate ; and the definitions destroy the 
 pretended demonstrations. Thus, mathe- 
 matical demonstration is found to be a rope 
 of sand. 
 
 I agree with this acute author, that, if 
 we could form no notion of points, lines, and 
 surfaces, more accurate than those we see 
 and handle, there could be no mathematical 
 demonstration. 
 
 But every man that has understanding, 
 by analysing, byabstnicting, and compound- 
 ing the rude materials exhibited by liis 
 senses, can fabricate, in his own mind, 
 those elegant and accurate forms of mathe- 
 matical lines, surfaces, and solids. [607] 
 
 If a man finds himself incapable of form- 
 ing a precise and determinate notion of the 
 figure which mathematicians call a cube, 
 he not only is no mathematician, but is in- 
 capable of being one. But, if he has a pre- 
 cise and determinate notion of that figure, 
 he must perceive that it is terminated by six 
 mathematical surfaces, perfectly square and 
 perfectly equal. He must perceive tliat 
 these surfaces are terminated by twelve 
 mathematical lines, perfectly straight and 
 perfectly equal, and that those lines are ter- 
 minated by eight mathematical points. 
 
 When a man is conscious of having these 
 conceptions distinct and determinate, as 
 every mathematician is, it is in vain to bring 
 metaphysical arguments to convince him 
 tliat they are not distinct. You may as well 
 bring arguments to convince a man racked 
 with pain that he feels no jiain. 
 
 Every theory that is inconsistent with our 
 having accurate notions of mathematical 
 lines, surfaces, and solids, must be false. 
 Therefore it follows, that they are not copies 
 of our impressions. 
 
 The Bledicean Venus is not a copy of the 
 block of marble from which it was made. 
 It is true, that the elegant statue was 
 formed out of the rude block, and that, too, 
 by a manual operation, which, in a literal 
 sense, we may call abstraction. Mathe- 
 
 [605-6071
 
 CHAP. VI.] FIRST PRINCIPLES OF NECESSARY TRUTHS. 
 
 453 
 
 matical notions are formed iu tlie under- 
 standing; by an abstraction of another kind, 
 out of the rude perceptions of our senses. 
 
 As the truths of natural philosophy are 
 not necessary truths, but continj^ent, de- 
 pending upon the will of the IMaker of the 
 world, the principles from which they are 
 deduced must be of tlie same nature, and, 
 therefore, belong not to this class. [608] 
 
 4. I think there are axioms, even in 
 matters of taste. Notwithstanding the 
 variety found among men, iu taste, there 
 are, I apprehend, some common principles, 
 even in matters of this kind. I never heard 
 of any man who thought it a beauty in a 
 human face to want a nose, or an eye, or to 
 have the mouth on one side. How many 
 ages have passed since the days of Homer ! 
 Yet, in this long tract of ages, there never 
 was found a man who took Thersites for a 
 beauty. 
 
 The fine arts are very properly called the 
 arts of taste, because the principles of both 
 are the same ; and, in the fine arts, we find 
 no less agreement among those who practise 
 them than among other artists. 
 
 Xo work of taste can be either relished 
 or understood by those v ho do not agree 
 with the author in tlie principles of taste. 
 
 Homer and Virgil, and Shakspeare and 
 Milton, had the same taste ; and all men 
 who have been acquainted with their writ- 
 ings, and agree in the admiration of them, 
 must have the same taste. 
 
 The fundamental rules of poetry and 
 music, and painting, and dramatic action and 
 eloquence, have been always the same, and 
 will be so to the end of the world. 
 
 The variety we find among men in matters 
 of taste, is easily accounted for, consistently 
 with what we have advanced. 
 
 There is a taste that is acquired, and a 
 taste that is natural. This holds with re- 
 spect both to the external sense of taste and 
 the internal. Habit and fashion have a 
 powerful influence upon both. 
 
 Of tastes that are natural, there are some 
 that may be called rational, others that are 
 merely animal. 
 
 Children are delighted with brilliant and 
 gaudy colours, with romping and noisy 
 niiith, with feats of agility, strength, or 
 cunning ; and savages have much the same 
 tas*e as children. [609] 
 
 But there are tastes that are more intel- 
 lectual- It is the dictate of our rational na- 
 ture, that love and admiration arc misjilaced 
 when there is no intrinsic worth in tho object. 
 
 In those operations of taste which are ra- 
 tional, we judge of the real worth and ex- 
 cellence of the object, and f»ur love or 
 admirati(in is guided by that judgment. In 
 8uch operations there Ib judgment as well 
 as feeling, and the feeling de)>ond3 upon 
 the judgment we form of the object. 
 [60B-01()J 
 
 I do not maintain that taste, so far as it 
 is acquired, or so far as it is merely animal, 
 can be reduced to principles. But, as far 
 as it is founded on judgment, it certainly may. 
 
 The virtues, the graces, the muses, have 
 a beauty that is intrinsic. It lies not in 
 the feelings of the spectator, but in the 
 real excellence of the ol)jeet. If we do not 
 perceive their beauty, it is owing to the de- 
 fect or to the perversion of our faculties. 
 
 And, as there is an original beauty in cer- 
 tain moral and intellectual qualities, so 
 there is a borrowed and derived beauty 
 in the natural signs and expressions of 
 such qualities. 
 
 The features of the human face, the mo- 
 dulations of the voice, and the proportions, 
 attitudes, and gesture of the body, are all 
 natural expressions of good or bad quali- 
 ties of the person, and derive a beauty or 
 a deformity from the qualities which they 
 express. 
 
 Works of art express some quality of 
 the artist, and often derive an additional 
 beauty from their utility or fitness for their 
 end. 
 
 Of such things there are some that 
 ought to please, and others that ought to 
 displease. If they do not, it is owing to 
 some defect in the spectator. But what 
 has real excellence will always please 
 those who have a correct judgment and a 
 sound heart. [610] 
 
 The sum of what has been said upon 
 this subject is, that, setting aside the 
 tastes which men acquire by habit and 
 fashion, there is a natural taste, which is 
 partly animal, and j)artly rational. With 
 regard to the first, all we can say is, 
 that the Author of nature, for wise rea- 
 sons, has formed us so as to receive plea- 
 sure from the contemplation of certain 
 objects, and disgust from others, before 
 we are capable of perceiving any real ex- 
 cellence in one or defect in the other. 
 But that taste which we may cull ration- 
 al, is that part of our constitution by 
 wliich we are made to receive pleasure 
 from the contemplation of what we con- 
 ceive to be excellent in its kind, the plea- 
 sure being annexed to this judgment, and 
 regulated by it. This taste may be true 
 or false, according as it is founded on a 
 true or false judgment. And, if it may be 
 true or false, it must have first principles. 
 
 5. There are also first principles iu mo- 
 rals. 
 
 That an unjust ncli:,n hai mure demerit 
 //inn an unf/enerous i.ne : Tliat a fiencrous 
 <:c.ion hus more merit lluni a merely just 
 one : 'J hut no man (lui/tit to he blmnid fur 
 wlial it teas not in his /intver to liin/er : That 
 we ought not to do to others what we would 
 think unjust or vrifair to be done to un in 
 like ciri:um.sla:ices. These arc nu)ral axioms,
 
 454 
 
 ON THE INTELLECTUAL POWERS. 
 
 [essay VI. 
 
 and many others might be named which ap- 
 pear to me to have no less evidence than 
 those of juathematics. 
 
 Some perhaps may think that our de- 
 terminations, either in matters of taste or 
 in morals, ought not to be accounted ne- 
 cessary truths : That they are grounded 
 upon the constitution of that faculty which 
 we call taste, and of that which we call 
 the moral sense or conscience ; which fa- 
 culties might have been so constituted as 
 to have given determinations different, or 
 even contrary to those they now give : 
 That, as there is nothing sweet or bitter 
 in itself, but according as it agrees or dis- 
 agrees with the external sense called taste ; 
 so there is nothing beautiful or ugly in it- 
 self, but according as it agrees or dis- 
 agrees with the internal sense, which we 
 also call taste ; and nothing morally good 
 or ill in itself, but according as it agrees 
 or disagrees with our moral sense. [611] 
 
 This indeed is a system, with regard to 
 morals and taste, which hath been supported 
 in modern times by great authorities. And 
 if this system be -true, the consequence 
 must be, that there can be no principles, 
 either of taste or of morals, that are neces- 
 sary truths. For, according to this system, 
 all our determinations, both with regard to 
 matters of taste, and with regard to morals, 
 are reduced to matters of fact — I mean to 
 such as these, that by our constitution we 
 have on such occasions certain agreeable 
 feelings, and on other occasions certain dis- 
 agreeable feelings. 
 
 But I cannot help being of a contrary 
 opinion, being persuaded that a man who 
 determined that polite behaviour has great 
 deformity, and that there is great beauty 
 in rudeness and ill-breeding, would judge 
 wrong, whatever his feelings were. 
 
 In like manner, I cannot help thinldng 
 that a man who determined that there is 
 more moral worth in cruelty, perfidy, and 
 injustice, than in generosity, justice, pru- 
 dence, and temperance, would judge wrong, 
 whatever his constitution was. 
 
 And, if it be true that there is judgment 
 in our determinations of taste and of morals, 
 it must be granted that what is true or 
 false in morals, or in matters of taste, is 
 necessarily so. For this reason, I have 
 ranked the first principles of morals and of 
 taste under the class of necessary truths. 
 
 6. The last class of first principles I shall 
 mention, we may call metaphysical. 
 
 I shall particularly consider three of these, 
 because they have been called in question 
 by Mr Hume. [G12] 
 
 The Jirst is, Thai the qualities which we 
 perceive by our senses mutt have a suhjrct, 
 which we call body, and that the thoughts 
 we are consciou<i of must have a subject, 
 which ive call mind. 
 
 It is not more evident that two and two 
 make four, than it is that figure cannot 
 exist, unless there be something that is 
 figured, nor motion without sometliing that 
 is moved. I not only perceive figure and 
 motion, but I perceive them to be qualities. 
 They have a necessary relation to some- 
 thing in which they exist as their subject. 
 The difficulty which some philosophers have 
 found in admitting this, is entirely owing to 
 the theory of ideas. A subject of the sen- 
 sible qualities which we perceive by our 
 senses, is not an idea either of sensation or 
 of consciousness ; therefore say they, we 
 have no such idea. Or, in the style of Mr 
 Hume, from what impression is the idea of 
 substance derived ? It is not a copy of any 
 impression ; therefore there is no such idea. 
 
 The distinction between sensible quali- 
 ties, and the substance to which they belong, 
 and between thought and the mind that 
 thinks, is not the invention of philosophers ; 
 it is found in the structure of all languages, 
 and therefore must be common to all men 
 who speak with understanding. And I 
 believe no man, however sceptical he may 
 be in speculation, can talk on the common 
 affairs of life for half an hour, without say- 
 ing things that imply his belief of the reality 
 of these distinctions. 
 
 Mr Locke acknowledges, " That we can- 
 not conceive how simple ideas of sensible 
 qualities should subsist alone ; and there- 
 fore we suppose them to exist in, and to be 
 supported by, some common subject." In 
 his Essay, indeed, some of his expressions 
 seem to leave it dubious whether this belief, 
 that sensible qualities must have a subject, 
 be a true judgment or a vulgar prejudice. 
 [613] But in his first letter to the Bishop 
 of Worcester, he removes this doubt, and 
 quotes many passages of his Essay, to shew 
 that he neither denied nor doubted of the 
 existence of substances, both thinking and 
 material ; and that he believed their ex- 
 istence on the same ground the Bishop 
 did — to wit, " on the repugnancy to our 
 conceptions, that modes and accidentsshould 
 subsist by themselves." He offers no proof 
 of this repugnancy ; nor, I think, can any 
 proof of it be given, because it is a first 
 principle. 
 
 It were to be wished that Mr Locke, who 
 inquired so accurately and so laudably into 
 the origin, certainty, and extent of human 
 knowledge, had turned his attention more 
 particularly to the origin of these two 
 opinions which he firmly believed ; to wit, 
 tliat sensible qualities must have a subject 
 which we call body, and that thought must 
 have a subject which we call mind. A due 
 attention to these two opinions which go- 
 vern the belief of all men, even of sceptics 
 in the practice of life, would probably have 
 led him to perceive, that sensation and 
 
 f 61 1-613]
 
 CHAP, vi.l FIRST PRINCIPLES OF NECESSARY TRUTHS. 
 
 45^ 
 
 consciousness are not the only sources of 
 human knowledge ; and that there are prhi- 
 ciples of belief in human nature, of which 
 we can give no other account but that they 
 necessarily result from the constitution of 
 our faculties ; and that, if it were in our 
 power to throw ofl' their influence upon our 
 practice and conduct, we could neither 
 speak nor act like reasonable men. 
 
 We cannot give a reason why we believe 
 even our sensations to be real and not fal- 
 lacious ; why we believe what we are con- 
 scious of; why we trust any of our natural 
 faculties. We say, it must be so, it cannot 
 be otherwise. This expresses only a strong 
 belief, which is indeed the voice of nature, 
 and which therefore in vain we attempt to 
 resist. But if, in spite of nature, we resolve 
 to go deeper, and not to trust our faculties, 
 without a reason to shew that they cannot 
 be fallacious, I am afraid, that, seeking to 
 become wise, and to be as gods, we shall 
 become foolish, and, being unsatisfied with 
 the lot of humanity, we shall throw off com- 
 mon sense. 
 ': The *eco;;rf metaphysical principle I men- 
 I tion is — That whatever begins to exist, must 
 have n cause which produced it.' [614] 
 
 Philosophy is indebted to Mr Hume in 
 this respect among others, that, by calling 
 in question many of the first princijiles of 
 human knowledge, he hath put speculative 
 men upon inquiring more carefully than was 
 done before into the nature of the evidence 
 upon which they rest. Truth can never 
 suffer b}' a fair inquiry ; it can bear to be 
 seen naked and in the fullest light ; and the 
 strictest examination will always turn out 
 in the issue to its advantage. I believe Mr 
 Hume was the first who ever called in 
 question whether things that begin to exist 
 must have a cause. 
 
 With regard to this point, we must hold 
 one of these three things, either that it is 
 an o])inion for which we have no evidence, 
 and which men have foolishly taken up 
 without ground ; or, secondly. That it is 
 capable of direct proof by argument ; or, 
 tliirdlij, Tiiat it is self-evident, and needs no 
 proof, but ought to be received as an axiom, 
 which cannot, by reasonable men, be called 
 hi question. 
 
 The first of these suppositions would put 
 an end to all philosophy, to all religion, to 
 all reasoning tliat would carry us beyond 
 the objects of sense, and to all prudence in 
 the conduct of life. 
 
 As to the second supposition, that this 
 principle may be proved by direct reason- 
 ing, I am afrai<l we shall find the proof 
 extremely difficult, if not altogether ini- 
 pOBsible. 
 
 I know only of three or four arguments 
 
 * Sec below, " rMi;)v«nn Ihc Active Powfr»,"p. 30, 
 • q— II. 
 
 that have been urged hy philosophers, in the 
 way of abstract reasoning, to prove that 
 things which begin to exist must have a cause. 
 
 One is offered by Mr Hobbes, another 
 by Dr Samuel Clarke, another by Mr Locke. 
 Mr Hume, in his ''Treatise of Human 
 Nature," has examined them all ;* and, in 
 my opinion, has shewn that they take for 
 granted the thing to be proved ; a kind of 
 false reasoning, which men are very apt to 
 fall into when they nttempt to prove what 
 is self-evident, [fil^)] 
 
 It has been thoug'it, that, although this 
 principle does not admit of proof from 
 abstract reasoning, it may be proved from 
 experience, and may be justly drawn by 
 induction, from instances that fall within 
 our observation. 
 
 I conceive this method of proof will leave 
 us in great uncertainty, for these threa 
 reasons : 
 
 \st. Because the proposition to be proved 
 is not a contingent but a necessary proposi- 
 tion. It is not that things which begin to 
 exist commonly have a cause, or even that 
 they always in fact have a cause ; but that 
 they must have a cause, and cannot begin 
 to exist without a cause. 
 
 Propositions of this kind, from their 
 nature, are incapable of proof by induction.. 
 Experience informs us only pf yyhat is or 
 liusbeen, hof "of what tnust^ be ; and the 
 conclusion must be of the same nature with 
 the premises.-f 
 
 For this reason, no mathematical propo- 
 sition can be proved by indHCtion. Though 
 it should be found by experience in a thou- 
 sand cases, that the area of a plane triangle 
 is equal to the rectangle under the altitude 
 and half the base, this would not prove that 
 it must be so in all cases, and cannot be 
 otherwise; which is what the mathematician 
 affirms. J 
 
 In like manner, though we had the most 
 ample experimental proof that things which 
 have begun to exist had a cause, this would 
 not prove that they must have a cause. 
 Experience may shew us what is the esta- 
 blished course of nature, but can never shew 
 what connections of things are in their 
 nature necessary. 
 
 2'////, General maxims, grounded on ex- 
 perience, have only a degree of probability 
 proportioned to the extent of our experience, 
 and ought always to be understood so as to 
 leave room for exceptions, if future expe- 
 rience shall discover any such. [610] 
 
 The law of gravitation has as full a proof 
 from experience and induction as any jirin- 
 ciplc can be supposed to liave. Yet, if any 
 philosopher should, by clear experiment, 
 
 * Vol. i.p. 14-1-I46.— H. 
 
 + Sec liflow, p. 627 ; and " Active Pnwoiii," p. Ill, 
 and ai ovo, p. 3-^:), a, note ♦.— H. 
 t So Arimotlfi.— H.
 
 456 
 
 ON THE INTELLECTUAL POWERS. 
 
 [ 
 
 ESSAY VI. 
 
 Bliew that there is a kind of matter in some 
 bodies which does not gravitate, the law 
 of gravitation ought to be Umited by that 
 exception. 
 
 ISovi, it is evident that men have never 
 considered the principle of the necessity of 
 causes, as a truth of this kind which may 
 admit of limitation or exception ; and there- 
 fore it has not been received upon this kind 
 of evidence. 
 
 3d:i/, I do not see that experience could 
 satisfy us that every ckange in nature act- 
 ually has a cause. 
 
 In the far greatest part of the changes in 
 nature that fall within our observation, the 
 causes are unknown ; and, therefore, from 
 experience, we cannot know whether they 
 have causes or not. 
 
 Caiisation, is not an object of sense. The 
 only experience we can have of it, is in the 
 consciousness we have of exerting some 
 power in ordering our thoughts and actions. 
 But this experience is surely too narrow a 
 foundation for a general conclusion, that 
 all things that have had or shall have a be- 
 ginning, must have a cause. 
 
 For these reasons, this principle cannot 
 be drawn from experiance, any more than 
 from abstract reasoning. 
 
 The third supposition is — That it is to be 
 admitted as a first or self-evident principle. 
 Two reasons may be urged for this. 
 
 1. The universal consent of mankind, not 
 of philosophers only, but of the rude and un- 
 learned vulgar. 
 
 Mr Hume, as far as I know, was the first 
 that ever expressed any doubt of this prin- 
 ciple.* And when we consider that he has re- 
 jected every principle of human knowledge, 
 excepting that of consciousness, and has not 
 even spared the axioms of mathematics, 
 his authority is of small weight. [617] 
 
 Indeed, with regard to first principles, 
 there is no reason why the opinion of a 
 philosopher should have more authority 
 than that of another man of common sense, 
 who has been accustomed to judge in such 
 cases. The illiterate vulgar are competent 
 judges ; and the philosopher has no preroga- 
 tive in matters of this kind ; but he is more 
 liable than they to be misled by a favourite 
 system, especially if it is his own. 
 
 Setting aside the authority of Mr Hume, 
 what has philosophy been employed in 
 since men first began to philosophise, but 
 ui the investigation of the causes of things ? 
 This it has always professed, when we trace 
 it to its cradle. It never entered into any 
 man's thought, before the philosopher we 
 have mentioned, to put the previous ques- 
 tion, whether things have a cause or not ? 
 Had it been thought possible that they 
 might not, it may be presumed that, in the 
 
 * Hume was i:ot the frst. — H. 
 
 variety of absurd and contraciictory causes 
 assigned, some one would have had recourse 
 to this hypothesis. 
 
 Tliey could conceive the world to arise 
 from an egg, from a struggle between love 
 and strife, between moisture and drought, 
 between heat and cold ; but they never sup- 
 posed that it had no cause. We know not 
 any athf'stic sect that ever had recourse 
 to this topic, though by it, they might have 
 evaded every argument that could be 
 brought against them, and answered all 
 objections to tlieir system. 
 
 Cut rather than adopt such an absurdity, 
 they contrived some imaginary cause — such 
 as chance, a concourse of atoms, or neces- 
 sity — as the cause of the universe. [618] 
 
 The accounts which philosophers have 
 given of particular phsenomena, as well as 
 of the universe in general, proceed upon 
 the same principle. That every phseno- 
 menon must have a cause, was always taken 
 for granted. Nil turpius phydco, says 
 Cicero, qnam fieri sine causa quicquum 
 dicerr. Though an Academic, he was dog- 
 matical in this. And Plato, the father of 
 the Academy, was no less so. " n«c>T( 
 
 ya,^ ochCfOcrov x^V^ a'niov yivlaiv sx^'^ • it IS mipOS- 
 
 sible that anything should have its origin 
 without a cause." — Tim^us. 
 
 I believe Mr Hume was the first who 
 ever held the contrary.* This, indeed, he 
 avows, and assumes the honour of the dis- 
 covery. " It is," says he, " a maxim in 
 philosophy, that whatever begins to exist, 
 must have a cause of existence. This is 
 commonly taken for granted in all reason- 
 ings, without any proof given or demanded. 
 It is supposed to be founded on intuition, 
 and to be one of those maxims which, 
 though they may be denied with the lips, 
 it is impossible for men in their hearts 
 really to doubt of. But, if we examine 
 this maxim by the idea of knowledge above 
 explained, we shall discover in it no mark 
 of such intuitive certainty." The meaning 
 of this seems to be, that it did not suit with 
 his theory of intuitive certa'uty, and, there- 
 fore, he excludes it from that [)rivilege. 
 
 The vulgar adhere to this maxim as 
 firmly and universally as the philosophers. 
 Their superstitions have the same origin 
 as the systems of philosophers — to wit, a 
 desire to know the causes of things. Fe/ix 
 qui potuit renim ccgnnsceie causas, is the 
 universal sense of men ; but to say that 
 anything can happen without a cause, shocks 
 the common sense of a savage. 
 
 This universal belief of mankind is easily 
 accounted for, if we allow that the neces- 
 sity of a cause of every event is obvious to 
 the rational powers of a man. But it is 
 impossible to account for it otherwise. It 
 
 * Sie liist note. — H. 
 
 [617, 618]
 
 CHAP VI.] FIRST PRINCIPLES OF NECESSARY TRUTHS. 
 
 457 
 
 cannot be ascribed to education, to systems 
 i)f philosopliy. or to jn-iestcraft. One 
 would think that a philosopher who takes 
 it to be a general delusion or prejudice, 
 would endeavour to shew from what causes 
 in human nature such a general error may 
 take its rise. But I forget that Mr Hume 
 might answer upon his own principles, that 
 since things may happen without a cause — 
 this error and delusion of men may be uui- 
 versal without any cause. [(>'!)] 
 
 2. A second reason why I conceive this 
 to be a first principle, is, That mankind not 
 only assent to it in speculation, but that the 
 practice of life is grounded upon it in the 
 most important matters, even in cases where 
 experieiice leaves us doubtful ; and it is 
 impossible to act with common prudence if 
 we set it aside. 
 
 In great families, there are so manv bad 
 thmgs done by a cer;ani personage, called 
 NnlioHr, that it is proverbial that there is 
 a Nobody about every house who does a 
 great deal of mischief ; and even where 
 there is the exactest inspection and govern- 
 ment, many events will happen of which no 
 other author can be found ; so that, if we 
 trust merely to experience in this matter, No- 
 body will be found to be a very active person, 
 and to have no inconsiderable share in the 
 management of afiairs. But whatever coun- 
 tenance tnis system may have from experi- 
 ence, it is too shocking to common sense to 
 impose upon the most ignorant. A child 
 knows that, when his top, or any of his pkiy- 
 things, are taken away, it must be done by 
 somebody. Perhaps it would •^lot be diffi- 
 cult to persuade him that it was done by 
 some invisible being, but that it should be 
 done by nobody he cannot believe. 
 
 Suppose a man's house to be broke open, 
 his money and jewels taken away. Such 
 things have happened times immmerable 
 without any ap[)arent cause ; and were he 
 only to reason from experience in such a 
 case, how must he behave ? He must put 
 in one scale the instances wherein a cause 
 was found of such an event, and in the other 
 scale the instances where no cause was 
 found, and the preponderant scale nmst 
 determine whether it be most j)robable that 
 there was a cause of this event, or tliat 
 there was none. Would any man of com- 
 mon understanding have recourse 1 1 such 
 an expedient todirect his judgment ? [020] 
 Suppose a man to lye iouiid dead on the 
 highway, his skull fractiireil, his body 
 pierced with deadly wounds, his watcli and 
 money carried off'. The coroner's jury sits 
 ujion the body ; and the question is put. 
 What was the cause of tiiis man's death ? — 
 was it accident, itrfeln de se, or nmrder by 
 persons unknown ? Let us suppose an 
 adept in iMr Huiiie's ])hilosoi)liy to make 
 one of the jury, and that he insists ujjon the 
 [fil9-621J 
 
 previous question, whether there was any 
 cause of the event, and whether it happened 
 without a cause. 
 
 Surely, upon Mr Hume's principles, a 
 great deal might be said upon this point ; 
 and, if the matter is to be determined by 
 past experience, it is dubious on which side 
 the weight of argument might stand. But 
 we may venture to say, that, if ISlr Hume 
 had been of such a jury, he would have laid 
 aside liis philosophical principles, and acted 
 according to the dictates of common pru- 
 dence. 
 
 Many passages might be produced, even 
 in Mr Hume's philosophical writings, iu 
 «hich he, unawares, betrays the same in- 
 ward conviction of the necessity of causes 
 which is common to other men. I shall 
 mention only one, in the "Treatise of Hu- 
 man Nature," and in that part of it where 
 he combats this very principle : — " As to 
 those ini[jressions," .says he, " which arise 
 from the senses, their ultimate cause is, in 
 my opinion, perfectly inexplicable by hu- 
 man reason ; and it will always be impos- 
 sible to decide with certainty whether they 
 arise immediately from the object, or are 
 produced by the creative power of the mind, 
 or are derived from the Author of our 
 being.'' 
 
 Among these alternatives, he never 
 thought of their not arising from any 
 cause.* [621] 
 
 The arguments which Mr Hume offers to 
 prove that this is not a self-evident i)rin- 
 ciple, are three. Firsl, That all certainty 
 arises from a comparison of ideas, and a 
 discovery of their unalterable relations, 
 none of which relations imply this proposi- 
 tion. That whatever has a begiiming nmst 
 have a cause of existence. This theory of 
 certainty has been examined before. 
 
 The second argument is, That whatever 
 we can conceive is possible. This has like- 
 wise been examined. 
 
 The //(i»rf argument is. That what we call 
 a cause, is only something antecedent to, 
 and always conjoined with, the eff'ect. This 
 is also one of Mr Hume's peculiar doctrines, 
 which we may have occasion to consider 
 afterwards. It is sufficient here to observe, 
 that we may leain from it that night is the 
 cause of day, and day the cause of night : 
 for no two things have more constantly 
 followed each other since the beginning of 
 the world. 
 
 The [third and] /".>' metaphysical prin- 
 ci|)le I mention, which is o])poscd by the 
 same author, i.s, T/kiI drsii;n tiiid intel/i- 
 gence in the causn mny be inferred, with \ 
 crrldinly, from iitarks or iiyits of it in the \ 
 fff'-rt. \ 
 
 * See abuve, p. 44V, iiole*. It ii the triumph nf 
 ircpticism to shew that fpfatlntinn and }>ractice are 
 irreconcilable. — H.
 
 458 
 
 ON THE INTELLECTUAL POWERS. 
 
 [essay VI. 
 
 Intelligence, design, and skill, are not 
 objects of the external senses, nor can we 
 be conscious of them in any person but our- 
 selves. Even in ourselves, we cannot, with 
 propriety, be said to be corscious of the 
 natural or acquired talents we possess. We 
 are conscious only of the operations of mind 
 in which they are exerted. Indeed, a man 
 comes to know his own mental abilities, 
 just as he knows another man's, by the 
 effects they produce, when there is occasion 
 to put them to exercise. 
 
 A man's wisdom is known to us only by 
 the signs of it in his conduct ; his eloquence 
 by the signs of it in his speech. In the same 
 manner, we judge of his virtue, of his forti- 
 tude, and of all his talents and virtues. [622] 
 Yet" it is to be observed, that we judge of 
 men's talents with as little doubt or hesita- 
 tion as we judge of the immediate objects 
 of sense. 
 
 One person, we are sure, is a perfect 
 idiot ; another, who feigns idiocy to screen 
 himself from punishment, is found, upon 
 trial, to have the imderstanding of a man, 
 and to be accountable for his conduct. We 
 perceive one man to be open, another cun- 
 ning; one to be ignorant, another very 
 knowing ; one to be slow of understanding, 
 another quick. Every man forms such 
 judgments of those he converses with ; and 
 the common affairs of life depend upon such 
 judgments. We can as little avoid them as 
 we can avoid seeing what is before our eyes. 
 From this it appears, that it is no less a 
 part of the human constitution, to judge of 
 men's characters, and of their intellectual 
 powers, from the signs of them in their 
 actions and discourse, than to judge of cor- 
 poreal objects by our senses ; that such 
 judgments are common to the whole human 
 race that are endowed with understanding ; 
 and that they are absolutely necessary in 
 the conduct of life. 
 
 Now, every judgment of this kind we 
 form, is only a particular application of the 
 general principle, that intelligence, wisdom, 
 and other mental qualities in the cause, 
 may be inferred from their marks or signs 
 in the effect. 
 
 The actions and discourses of men are 
 effects, of which the actors and speakers 
 are the causes. The effects are perceived 
 by our senses ; but the causes are behind 
 the scene. We only conclude their exist- 
 ence and their degrees from our observa- 
 tion of the effects. 
 
 From wise conduct, we infer wisdom in 
 the cause ; from brave actions, we infer 
 courage ; and so in other cases. [f>23] 
 
 This inference is made with perfect secu- 
 rity by all men. We cannot avoid it ; it 
 is necessary in the ordmary conduct of 
 life ; it has therefore the strongest marks of 
 being a first principle. 
 
 Perhaps some may think that this prin- 
 ciple may be learned either by reasoning or 
 by experience, and therefore that there ia 
 no ground to think it a first principle. 
 
 If it can be shewn to be got by reasoning, 
 by all, or the greater part of those who are 
 governed by it, I shall very readily ac- 
 knowledge that it ought not to be esteemed 
 a first principle. But I apprehend the con- 
 trary a[ipears from very convincing argu- 
 ments. 
 
 First, The principle is too universal to 
 be the effect of reasoning. It is common 
 to philosophers and to the vulgar ; to the 
 learned and to the must illiterate ; to the 
 civilized and to the savage. And of those 
 who are governed by it, not one in ten 
 thousand can give a reason for it. 
 
 Secondly, We find philosophers, ancient 
 and modern, who can reason excellently in 
 subjects that admit of reasoning, when they 
 have occasion to defend this principle, not 
 offering reasons for it, or any medium of 
 proof, but appealing to the common sense 
 of mankind ; mentioning particular instan- 
 ces, to make the absurdity of the contrary 
 opinion more apparent, and sometimes 
 using the weapons of wit and ridicule, which 
 are very proper weapons for refuting ab- 
 surdities, but altogether improper in points 
 that are to be determined by reasoning. 
 
 To confirm this observation, I shall quote 
 two authors, an ancient and a modern, who 
 have more expressly undertaken the defence 
 of this principle than any others I remem- 
 ber to have met with, and whose good 
 sense and ability to reason, where reasoning 
 is proper, will not be doubted. [624] 
 
 The first is Cicero, whose words, {Lb. 1. 
 cap. 13. De Divinalione,) may be thus 
 translated. 
 
 " Can anything done by chance have all 
 the marks of design ? Four dice may by 
 chance turn up four aces ; but do you think 
 that four hundred dice, thrown by chance, 
 will turn up four hundred aces ? Colours 
 thrown upon canvas without design may 
 have some similitude to a human face ; but 
 do you think they might make as beautiful 
 a picture as that of the Coan Venus ? A 
 hog turning up the ground with his nose 
 may make something of the form of the let- 
 ter A ; but do you think that a hog might 
 describe on the ground the Andromache of 
 Ennius ? Carneades imagined that, in the 
 stone quarries at Chios, he found, in a stone 
 that was split, a representation of the head 
 of a little Pan, or sylvan deity. I believe he 
 might find a figure not unlike j but surely not 
 such a one as you would say had been formed 
 by an excellent sculptor like Scopas. For 
 so, verily, the case is, that chance never 
 perfectly imitates design.'* Thus Cicero.* 
 
 * See also Cicero "De Natura De(in(m,"-\.'i\. c. 
 37.— H.
 
 CHAP. vi.J FIRST PRINCIPLES OF NECESSARY TRUTHS. 
 
 459 
 
 Now, in all this discourse, I see very 
 good sense, and what is apt to convince 
 every unprejudiced mind ; but I see not in 
 the whole a single step of re.isoning. It is 
 barely an appeal to every man's common 
 sense. 
 
 - Let us next see how the same point is 
 handled by the excellent Archbishop Tillot- 
 son. (1st Sermon, vol. i.) 
 
 " For I appeal to any man of reason, 
 whether anything can be more unreasonable 
 than obstinately to impute an efiect to chance 
 which carries in the fiice of it all the argu- 
 ments and characters of design ? Was ever 
 any considerable work, in which there was 
 required a great variety of parts, and an 
 orderly and regular adjustment of these 
 parts, done by chance ? Will chance fit 
 means to ends, and that in ten thousand 
 instances, and not fail in any one ? [G25] 
 How often might a man, after he had jumbled 
 a set of letters in a bag, fling them out upon 
 the ground before tliey would fall into an 
 exact poem, yea, or so much as make a 
 good discourse in prose ? And may not a 
 httle book be as easily made as this great 
 volume of the world ? How long miglit a 
 man sprinkle colours upon canvass with a 
 careless hand, before they would make the 
 exact picture of a man ? And is a man 
 easier made by chance than his picture ? 
 How long might twenty thousand blind men, 
 which should be sent out from the remote 
 parts of England, wander up and down be- 
 fore they would all meet upon Salisbury 
 plains, andfall into rank and file in the exact 
 order of an army ? And yet this is much 
 more easj' to be imagined than how the 
 innumerable blind parts of matter should 
 rendezvous themselves into a word. A man 
 tliat sees Henry VII.'s chapel at West- 
 minster might, with as good reason, main- 
 tain, (yea, and much better, considering the 
 vast dift'erence between tiiat little structure 
 and the huge fabric of the world,) that it 
 was never contrived or built by any man, 
 but tliat the stones did by chance grow into 
 those curious figures into which we see them 
 to hive been cut and graven ; and that, upon 
 a time, (as tales usually begin,) the mate- 
 rials of that building — the stone, mortar, 
 timber, iron, lead, and glass — hapj)ily met 
 together, and very fortunately ranged them- 
 selves into that delicate order in which we 
 see them now, so close compacted that it 
 must be a very great chance that parts them 
 again. What would the world think of a 
 man that should advance such an opinion 
 as this, and write a book for it ? If they 
 would do him right, they ought to look uimn 
 him as mad. liut yet he miglit niainlaiii 
 this opinion with a little more reason than 
 any man can have to say that the world was 
 made by chance, or that the first men grew 
 out of the earth, as [ilanti do now ; for, can 
 '"625-627] 
 
 anything be more ridiculous and against all 
 reason, than to ascribe the production of 
 men to the first fruitfulness of the earth, 
 without so much as one instance or experi- 
 ment in any age or history to countenance 
 so monstrous a supposition ? The thin"- ia 
 at first sight so gross and palpable, that no 
 discourse about it can make it more appa- 
 rent. And yet these shameful beggars of 
 principles, who give this precarious account 
 of the original of things, assume to them- 
 selves to be the men of reason, the great 
 wits of the world, the only cautious and wary 
 persons, who hate to be imposed upon, that 
 must have convincing evidence for every- 
 thing, and can admit nothing without a clear 
 demonstration for it. [(i'iU] 
 
 In this passage, the excellent author takes 
 what I conceive to be the proper method of 
 refuting an absurdity, by exposing it in dif- 
 ferent lights, in which every man of common 
 understanding conceives it to be ridiculous. 
 And, although there is much good sense, as 
 well as wit, in the passage I have quoted, I 
 cannot find one medium of proof in the 
 whole. 
 
 I have met with one or two respectable 
 authors who draw an argument from the 
 doctrine of chances, to shew how impro- 
 bable it is that a regular arrangement of 
 parts should be the ett'ect of chance, or that 
 it should not be the effect of design, 
 
 I do not object to this reasoning ; but I 
 would observe that the doctrine of chances 
 is a branch of mathematics little more than 
 an hundred years old. But the conclusion 
 drawn from it has been held by all men from 
 the beginning of the world. It cannot, 
 therefore, be thought that men have been 
 led to this conclusion by that reasoning. 
 Indeed, it may be doubted whether the first 
 principle upon which all the mathematical 
 reasoning about chances is grounded, is 
 more self-evident than this conclusion drawn 
 from it, or whether it is not a particular 
 instance of that general conclusion. 
 
 We are next to consider whether we may 
 not learn this truth from experience. That 
 ( fleets which have all the marks and tokens 
 of design, nuist proceed from a designing 
 cause. L**-?] 
 
 I apprehend that we cannot learn this 
 truth from experience for two reasons. 
 
 First, Because it is a necessary truth, 
 not a contingent one. It agrees with the 
 experience of mankind since the beginning 
 of the world, that the area of a triangle is 
 equal to half the rectangle under its base 
 and peri)en(lieular. It agrees no less with 
 experience, that the sun rises in the east 
 and sets in the west. So far as experience 
 goes, these truths are upon an equal footing. 
 But every man perceives this distinction 
 between them — that the first is ii necessary 
 truth, and that it is inipossililcit sjiouldnot
 
 460 
 
 ON THE INTELLECTUAL POWERS. 
 
 [^ESSAV 
 
 VI. 
 
 be true ; but the last is not necessary, but 
 contingent, depending upon the will of llini 
 who made the world. As we cannot learn 
 from experience that twice three must ne- 
 cessarily make six, so neither can we learn 
 from experience that certain effects must 
 proceed from a designing and intelligent 
 cause. Experience informs us only of what 
 has been, but never of what must be.* 
 
 Secondlji, It may be observed, that ex- 
 perience can shew a connection between a 
 sign and the thing signified by it, in those 
 cases only where both the sign and thing 
 signified are perceived and have always 
 been perceived in conjunction. But, if there 
 be any case where the sign only is per- 
 ceived, experience can never shew its con- 
 nection with the thing signified. Thus, for 
 example, thtiught is a sign of a thinking 
 principle or mind. But how do we know 
 that thought cannot be witliout a mind ? If 
 any man should say that he knows this by 
 experience, he deceives himself. It is im- 
 possible he can have any experience of this ; 
 because, though we have an immediate 
 knowledge of the existence of thought in 
 ourselves by consciousness, yet we have no 
 immediate knowledge of a mind. The mind 
 is not an immediate object either of sense 
 or of consciousness. We may, therefore, 
 justly conclude, that the necessary con- 
 nection between thought and a mind, or 
 thinking being, is not learned from expe- 
 rience. [628] 
 
 The same reasoning may be applied to 
 the connection between a work excellently 
 fitted for some purpose, and design in the 
 author or cause of that work. One of tliese 
 — to wit, the work — may be an immediate 
 object of perception. But the design and 
 purpose of the author cannot be an imme- 
 diate object of perception ; and, therefore, 
 experience can never inform us of any con- 
 nection between the one and the other, far 
 less of a necessary connection. 
 
 Thus, I think, it apfwars, that the prin- 
 ciple we have been considering — to wit, 
 that from certain signs or indications in the 
 effect, we may infer that there must have 
 been intelligence, wisdom, or other intel- 
 lectual or moral qualities in the cause, is a 
 principle which we get, neither by reason- 
 ing nor by experience ; and, therefore, if it 
 be a true principle, it must be a first prin- 
 ciple. There is in the human understand- 
 ing a light, by which we see immediately 
 tlie evidence of it, when there is occasion 
 to apply it. 
 
 Of how great importance this principle 
 is in common life, we have already observed. 
 And I need hardly mention its importance 
 in natural theology. 
 
 The clear marks and signatures of wis- 
 
 • See above p. til5; and " Active Powerr.,"p. ol. — H. 
 
 dom, power, and goodness, in the consti- 
 tution and government of the world, is, of 
 all arguments that have been advanced for 
 the being and providence of the Deity, that 
 which in all ages has made the strongest 
 impression upon candid and thinking minds ; 
 an argument, which has this peculiar ad- 
 vantage, that it gathers strength as human 
 knowledge advances, and is more convincing 
 at present than it was some centuries ago. 
 
 King Alphonsus might say, that he could 
 contrive a better planetary system than that 
 which astronomers held in his day.* That 
 system was not the work of God, but the 
 fiction of men. [G29] 
 
 But since the true system of the sun, 
 moon, and planets, has been discovered, no 
 man, however atheistically disposed, has 
 pretended to shew how a better could be 
 contrived. 
 
 When we attend to the marks of good 
 contrivance which appear in the works of 
 God, every discovery we make in the con- 
 stitution of the material or intellectual 
 system becomes a hymn of praise to the 
 great Creator and Governor of the world. 
 And a man who is possessed of the genuine 
 spirit of philosophy will think it impiety to 
 contaminate the divine workmanship, by 
 mixing it with those fictions of human fancy, 
 called theories and hypotheses, which will 
 always bear the signatures of human folly, 
 no less than the other does of divine wis- 
 dom. 
 
 I know of no person who ever called in 
 question the principle now under our consi- 
 deration, when it is applied to the actions 
 and discourses of men. For this would be to 
 deny that we have any means of discerning 
 a wise man from an idiot, or a man that is 
 illiterate in the highest degree from a man 
 of knowledge and learning, which no man 
 has the efl'rontery to deny. 
 
 But, in all ages, those who have been 
 unfriendly to the principles of religion, have 
 made attempts to weaken the force of the 
 argument for the existence and perfec- 
 tions of the Deity, which is founded on this 
 principle. That argument has got the name 
 of the argument from final causes ; and as 
 the meaning of this name is well understood, 
 we shall use it. 
 
 The argument from final causes, when re- 
 duced to a syllogism, has these two premises : 
 — First, That design and intelligence in the 
 cause, may, with certainty, be inferred from 
 marks or signs of it in the effect. This is 
 the principle we have been considering, and 
 
 * Alphonso X. of Castile. He flourished in the 
 thirteentli ccntury~a great mathematician and as- 
 tronomer. To him we owe the Alphonsine J'ables. 
 Hi* saying was not so pious and philo>ophical as Koid 
 states ; but that, " Had he been present with God 
 at the creation, he cculd have supplied some useful 
 hmts towards the better ordering of the universe." 
 — H. 
 
 [628. 629]
 
 CHAP. VI.] FIRST I'RINXIPLES OF NECESSARY TRUTHS. 
 
 4(n 
 
 we may call it the mujjr proDOsition of the 
 argument. The secjn /, which we call the 
 minor proposition, is, That there are in fact 
 the clearest marks of design and wisdom in 
 the works of nature ; and the cjnc/iision is, 
 That the works of nature are the eifects 
 of a wise and intelligent Cause. One must 
 either assent to the conclusion, or deny one 
 or other of the premises. [G30] 
 
 Those among the ancients who denied a 
 God or a Providence, seem to me to have 
 yielded the major proposition, and to have 
 denied the minor ; conceiving that there 
 are not in the constitution of things such 
 marks of wise contrivance as are sufficient 
 to put the conclusion beyond doubt. This, 
 I think, we may learn, from the reasoning 
 of Cotta the academic, in the third book of 
 Cicero, of the Nature of the Gods. 
 
 The gradual advancement made in the 
 knowledge of nature, hath put this opinion 
 quite out of countenance. 
 
 When the structure of the human body 
 was much less known than it is now, the 
 famous Galen saw such evident marks of 
 wise contrivance in it, that, though he had 
 been educated an Epicurean, he renounced 
 that system, and wrote his book of the use 
 of the parts of the human body, on purpose 
 to convince others of what a]ipeared so clear 
 to himself, that it was impossiljle that such 
 admirable contrivance should be the effect 
 of chance. 
 
 Those, therefore, of later times, who are 
 dissatisfied with this argument froui final 
 causes, have quitted the stronghold of the 
 ancient atheists, which had become un- 
 tenable, and have chosen rather to make a 
 defence against the major proposition. 
 
 Des Cartes seems to have led the way in 
 this, though he was no atheist. But, having 
 invented s ime new arguments for the being 
 of God, he was, perhaps, led to disparage 
 those that had been used before, that he 
 might bring more credit to his own. Or 
 perhaps he was offended with the i'eripa- 
 tetics, because they often mixed final causes 
 with physical, in order to account for the 
 phijenomena of nature. [G31 ] 
 
 He maintained, therefore, that physical 
 causes only should lie assigned for phieno- 
 mena ; that the philosopher has nothing to 
 do with final causes ; and that it is prc- 
 Bumption in us to pretend to determine for 
 what end any work of nature is framed. 
 Some of those who nere great admirers of 
 Des Cartes, and followed him in many 
 points, differed from liim in this, particu- 
 larly L)r Henry More and the pious Arcli- 
 bishop Feiielon : but others, after the ex- 
 ample of l)es Cartes, have shewn a contemj)! 
 of all reasoning from final causes. Among 
 these, I think, we may reckon Maiipertuis 
 and JJiiffon. But the most direct attack 
 has been made upon this principle by Mr 
 [630-C3'iJ 
 
 Hume, who puts an argument in the mouth 
 of an Epicurean, on which he seems to lay 
 great stress. 
 
 The argument is, That the universe is a 
 singular effect, and, therefore, we can draw 
 no conclusion from it, whether it may have 
 been made by wisdom or not." 
 
 If I understand the force of this argu- 
 ment, it amounts to this. That, if we had 
 been accustomed to see worlds produced, 
 some by wisdom and others without it, and 
 had observed that such a world as this 
 which we inhabit was always the effect of 
 wisdom, we might then, from past experi- 
 ence, conclude that this world was made 
 by wisdom ; but, having no such experi- 
 ence, we have no means of forming any 
 conclusion about it. 
 
 That this is the strength of the argument 
 appears, because, if the marks of wisdom 
 seen in one world be no evidence of wisdom, 
 the like marks seen in ten thousand will 
 give as little evidence, unless, in time past, 
 we perceived wisdom itself coL.joined with 
 the tokens of it ; and, from their perceived 
 conjunction in time past, conclude that, al- 
 though, in the present world, we see only 
 one of the two, the other must accompany 
 it. [G32] 
 
 Whence it appears that this reasoning of 
 Mr Hume is built on the supposition that 
 our inferring design from the strongest 
 marks of it, is entirely owing to our past 
 experience of having always found these 
 two things conjoined- But I hope I have 
 made it evident that this is not the case. 
 And, indeed, it is evident that, according 
 to this reasoning, we can have no evidence 
 of mind or design in any of our fellow- 
 men. 
 
 How do I know that any man of my ac- 
 quaintance has understanding ? I never 
 saw his understanding. 1 see only cer- 
 tain effects, which my judgment leads 
 me to conclude to be marks and tokens 
 of it. 
 
 But, says the sceptical philosopher, you 
 can conclude nothing from these tokens uii- 
 hss past experience has informed you that 
 such tokens are always joined witli under- 
 standing. Alas! sir, it is iuiposbible 1 can 
 ever have this experience. The iiiiderstand- 
 ing of another man is no immediate object 
 of sight, or of any other faculty which CJod 
 hath given me ; and unless I can conclude 
 its existence from tokens that are visible, I 
 have no evidence that there is understand- 
 ing in any man. 
 
 It seems, then, that the man who main- 
 tains that there is no force in the argument 
 from final causes, must, if lie will bo con- 
 sistent, see no evidence of the existence of 
 jiny intelligent being but himself. 
 
 * See Stewart ■« " Elements," li. p. 57l».— H.
 
 462 
 
 ON THE INTELLECTUAL POWERS. 
 
 [essay vt. 
 
 CHAPTER VIL 
 
 OPINIONS, ANCIENT AND MODERN, ABOL'T 
 FIRST PRINCIPLES. 
 
 I KNOW no writer wlio has treated ex- 
 pressly of first principles before Aristotle ; 
 but it is probable that, in the ancient Py- 
 thagorean pcliool, from which both Plato 
 and Aristotle borrowed much, this subject 
 had not been left untouched. [(J33] 
 
 Before the time of Aristotle, considerable 
 progress liad been made in the mathema- 
 tical sciences, particularly in geometry. 
 
 The discovery of the forty-seventh pro- 
 position of the first bouk of Euclid, and of 
 the five regular solids, is, by antiquity, 
 ascribed to Pythagoras himself; and it is 
 hnpossible he could have made those dis- 
 coveries without knowing many other pro- 
 positions in mathematics. Aristotle men- 
 tions the incommensurability of the diagonal 
 of a square to its side, and gives a hint of 
 the manner in which it was demonstrated. 
 We find likewise some of the axioms of 
 geometry mentioned by Aristotle as axioms, 
 and as indemonstrable principles of mathe- 
 matical reasoning. 
 
 It is probable, therefore, that, before the 
 time of Aristotle, there were elementary 
 treatises of geometry, which are now lost ; 
 and that in them the axioms were distin- 
 guished from the propositions which require 
 1 roof. 
 
 To suppose that so perfect a system as 
 that of Euclid's " Elements" was produced 
 by one man, without any preceding model 
 or materials, would be to suppose Euclid 
 more than a man. We ascribe to him as 
 much as the weakness of human under- 
 standing will permit, if we suppose that the 
 hiventions in geometry, which had been 
 made in a tract of preceding ages, were by 
 him not only carried much farther, but 
 digested into so admirable a system that 
 his work obscured all that went before it, 
 and made them be forgot and lost. 
 
 Perhaps, in like manner, the writings of 
 Aristotle with regard to first principles, and 
 with regard to many other abstract subjects, 
 may have occasioned the loss of what had 
 been written upon those subjects by more 
 ancient philosophers. [G34] 
 
 Whatever may be in this, in his second 
 book ujion demonstration, he has treated 
 very fully of first principles ; and, though he 
 has not attempted any enumeration of them, 
 he shews very clearly that all demonstra- 
 tion must be built upon truths which are 
 evident of themselves, but cannot be de- 
 monstrated. His whole doctrine of syllo- 
 gisms is grounded upon a few axioms, from 
 which he endeavours to demonstrate the 
 rules of syllogism iu a mathematical way ; 
 
 and in his topics he points out many of the 
 first principles of probable reasoning. 
 
 As long as the philosophy of Aristotle 
 prevailed, it was held as a fixed point, tliat 
 all proof must be drawn from jirinciples 
 already known and granted. 
 
 We must observe, however, that, in that 
 philosophy, many things were assumed as 
 first principles, which have no just claim 
 to that character : such as, that the eaith 
 is at rest ; that nature abhors a vacuum ; 
 that there is no change in the heavens above 
 the sphere of the moon ; that the heavenly 
 bodies move in circles, that being the most 
 perfect figure ; that bodies do not gravitate 
 in their proper place ; and many others. 
 
 The Peripatetic philosophy, therefore, 
 instead of being deficient in first principles, 
 was redundant ; instead of rejecting those 
 that are truly such, it adopted, as first 
 principles, many vulgar prejudices and rash 
 judgments : and this seems in general to 
 have been the spirit of ancient philosophy.* 
 
 It is true, there were among the ancients 
 sceptical philosophers, who professed to have 
 no principles, and held it to be the greatest 
 virtue in a philosopher to withhold assent, 
 and keep his judgment iu a perfect equil - 
 brium between contradictory opinions. But, 
 though this sect was defended by some per- 
 sons of great erudition and acuteness, it died 
 of itself, and the dogmatic philosophy of 
 Aristotle obtained a complete triumph over 
 it. [G35] 
 
 What Mr Hume says of those who are 
 sceptical with regard to moral distinctions 
 seems to liave had its accomplishment in 
 the ancient sect of Sceptics. " The only 
 way," says he, " of converting antagonists 
 of this kind is to leave them to themselves ; 
 for, finding that nobidy keeps up the con- 
 troversy with them, it is jirobable they will 
 at last of themselves, from mere weariness, 
 come over to the side of common sense and 
 reason." 
 
 Setting aside this small sect of the Scep- 
 tics, which was extinct many ages before the 
 authority of Aristotle declined, I know of 
 no opposition made to first principles among 
 the ancients. The disposition was, as has 
 Ijeen observed, not to oppose, but to mul- 
 tiply them beyond measure. 
 
 Men have always been prone, when they 
 leave one extreme, to run into the opposite ; 
 and this spirit, in the ancient philosophy, to 
 multiply first principles beyond reason, was 
 a strong presage that, when the autliority 
 of the Peripatetic system was at an, end, 
 
 * The Peripatetic philosophy did not assutvie any 
 f uch principles as original anil .self evident ; but pro. 
 fcsscdto establish them all upon induction and gene- 
 lalization. In practice its induction (f instances 
 might be imperfect, and its generalization from par. 
 ticulars raJi ; but in theory, at least, it was correct. 
 — H. 
 
 633-6351
 
 CHAP, 
 
 V,I.] 
 
 OPINIONS ABOUT FIRST PRINCIPLES. 
 
 463 
 
 the next reigning system would diminish 
 their number beyond reason. 
 
 This, accordingly, happened in that great 
 revolution of the philosophical republic 
 brought about by Des Cartes. Tbat truly 
 great reformer in philosophy, cautious to 
 avoid the snare in which Aristotle was 
 taken, of admitting things as first principles 
 too rashly, resolved to doubt of everything, 
 and to withhold his assent, until it was forced 
 by the clearest evidence.* 
 
 Thus Des Cartes brought himself into 
 that very state of suspense which the an- 
 cient Sceptics recommended as the highest 
 perfection of a wise man, and the only road 
 to tranquillity of mind. Eut he did not 
 remain long in this state ; his doubt did 
 not arise from despair of finding the truth, 
 but from caution, that he might not be im- 
 posed upon, and embrace a cloud instead of 
 a goddess. [G3(J] 
 
 His very doubting convinced him of his 
 own existence ; for that which does not exist 
 can neither doubt, nor believe, nor reason. 
 
 Thus he emerged from universal scepti- 
 cism by this short euthymeme, Cogito, eryo 
 sum. 
 
 This enthymeme consists of an antece- 
 dent proposition, / l/iiuk, and a conclusion 
 drawn from it, therefhre I exist. 
 
 If it should be asked how Des Cartes 
 came to be certain of the antecedent proposi- 
 tion, it is evident that for this he trusted to 
 the testimony of consciousness. He was con- 
 scious that he thought, and needed no other 
 argument. 
 
 So that the first principle which he adopts 
 in this famous euthymeme is this. That those 
 doubts, and thoughts, and reasonings, of 
 which he was conscious, did certainly exist, 
 and that his consciousness put their exist- 
 ence beyond all doubt. 
 
 It might have been objected to this first 
 principle of Des Cartes, How do you know 
 that your consciousness cannot deceive you ? 
 You have supposed that all you see, and 
 hear, and handle, may be an illusion. Why, 
 therefore, should the power of conscious- 
 ness have this prerogative, to be believed 
 implicitly, when all our other powers are 
 supjiosed fallacious ? 
 
 To this objection I know no other answer 
 that can be made but that we find it im- 
 possible to doubt of things of wliich we are 
 conscious. The constitution of our nature 
 forces this belief upon us irresistibly. 
 
 This is true, and is sullicient to justify 
 Des Cartes in assuming, as a first princij)le, 
 the existence of thought, of which he was 
 conscious. IC'l?] 
 
 He ought, however, to have gone farther 
 in this track, and to have considered whe- 
 ther there may not be other first principles 
 
 * On the Cartegian doubt, see Note H.— H. 
 [■636-038] 
 
 which ought to be adopted for the same 
 reason. But he did not see this to be ne- 
 cessary, conceiving that, upon this ona first 
 principle, he could support the whole fabric 
 of human knowledge. 
 
 To proceed to the conclusion of Des 
 Cartes's enthymeme. From the existence 
 of his thought he infers his own existence. 
 Here he assumes another first principle, 
 not a contingent, but a necessary one ; to 
 wit, that, where there is thought, there 
 must be a thinking being or mind. 
 
 Having thus established his own exist- 
 ence, he proceeds to prove the existence of 
 a supreme and infinitely perfect Being ; 
 and, from the perfection of the Deity, he 
 infers that his senses, his memory, and the 
 other faculties which God had given him, 
 are not fallacious. 
 
 Whereas other men, from the beginning 
 of the world, had taken for granted, as a t^rst 
 principle, the truth and reality of what they 
 perceive by their senses, and from thence 
 inferred the existence of a Supreme Author 
 and Maker of the world, Des Cartes took 
 a contrary course, conceiving that the tes- 
 timony of our senses, and of all our facul- 
 ties, excepting that of consciousness, ought 
 not to be taken for granted, but to be 
 proved by argument. 
 
 Perhaps some may think that Des Car- 
 tes meant only to admit no other first prin- 
 ciple of contingent truths besides that of 
 consciousness ; but that he allowed the axi- 
 oms of mathematics, and of other necessary 
 truths, to be received without proof. [638] 
 
 But I apprehend this was not his inten- 
 tion ; for the truth of mathematical axioms 
 must depend upon the truth of the faculty 
 by which we judge of them. If the faculty 
 be fallacious, we may be deceived by trust- 
 ing to it. Therefore, as he supposes that 
 all our faculties, excepting consciousness, 
 may be fallacious, and attempts to prove 
 by argument that they are not, it follows 
 that, accordhig to his principles, even ma- 
 thematical axioms require proof. Neither 
 did he allow that there are any necessary 
 truths, but maintained, that the truths 
 which are commonly so called, depend up- 
 on tiie will of God. And we find his fol- 
 lowers, who may be supposed to under- 
 stand his principles, agree in maintaining, 
 that the knowledge of our own existence is 
 the first and fundamental jirinciple from 
 which all knowledge nmst be deduced by 
 one who proceeds regularly in philosophy. 
 
 There is, no doubt, a beauty in raising a 
 large fabric of knowledge upon a few first 
 1/rinciples. The stately fabric of niathema- 
 ticai knowledge, raised u]ion the foundation 
 of a few axioms and delinltionH, cburiiia 
 every beholder. Des Cartes, who was well 
 acquainted with this lieauty in the nuithe- 
 matical sciences, Bccnis to have bciMi am
 
 464 
 
 ON THE INTELLECTUAL POWERS. 
 
 [epsay 
 
 VI. 
 
 bitious to give the same beautiful simplicity 
 to his system of philosophy ; and therefore 
 Bought only one first principle as the founda- 
 tion of all our knowledge, at least of con- 
 tingent trutlis. 
 
 And so far has his authority prevailed, 
 that those who came after him have 
 almost univer.sally followed him in this 
 track. This, therefore, may be considered 
 as the spirit of modern philosophy, to allow 
 of no first principles of contingent truths 
 but this one, that the thoughts and opera- 
 tions of our own minds, of which we are 
 conscious, are self-evidcntly real and true ; 
 but that everything else that is contingent 
 is to be proved by argument. 
 
 The existence of a material world, and 
 of what we perceive by our senses, is not 
 self-evident, according to this philosophy. 
 Des Cartes founded it upon this argument, 
 that God, wlio hath given us our senses, 
 and all our faculties, is no deceiver, and 
 therefore they are not fallacious. [639] 
 
 I endeavoured to shew that, if it be not 
 admitted as a first principle, that our facul- 
 ties are not fallacious, nothing else can be 
 admitted ; and that it is impossible to prove 
 this by argument, unless God should give us 
 new faculties to sit in judgment upon the old. 
 Father IMalebrauche agreed with Des 
 Cartes, that the existence of a material 
 world requires prof ; but, being dissatisfied 
 with Des Cartes's argument from the per- 
 fection of the Deity, thought that the only 
 solid proof is from divine revelation. 
 
 Arnauld, who was engaged in controversy 
 with Malebranche, approves of his anta- 
 gonist in offering an argument to prove the 
 existence of the material world, but objects 
 to the solidity of his argument, and offers 
 other arguments of his own. 
 
 Mr Norris, a great admirer of Des Cartes 
 and of Malebranche, seems to have thought 
 all the arguments oifered by them and by 
 Arnauld to be weak, and confesses that we 
 have, at best, only probable evidence of the 
 existence of the material world. 
 
 Mr Locke acknowledges that the evidence 
 we have of this point is neither intuitive 
 nor demonstrative ; yet he thinks it may 
 be called knowledge, and distinguishes it 
 by the name of sensitive knowledge ; and, 
 as the ground of this sensitive knowledge, 
 he offers some weak arguments, which would 
 rather tempt one to doubt than to believe. 
 
 At last. Bishop Berkeley and Arthur 
 Collier, without any knowledge of each 
 other, as far as appears by their writings, 
 undertook to prove, that there neither is 
 nor can be a material world. The excel- 
 lent style and elegant composition of the 
 former have made his writings to be known 
 and read, and this sy.stem to be attributed 
 to him only, as if Collier had never ex- 
 isted. [640] 
 
 Both, indeed, owe so much to Male- 
 branche, that, if we take out of his system 
 the peculiarities of our seeing all things in 
 God, and our learning the existence of an 
 external world from divine revelation, what 
 remains is just the system of Bishop Berke- 
 ley. I make this observation, by the way, 
 in justice to a foreign author, to whom 
 British authors seem not to have allowed 
 all that is due.* 
 
 Mr Hume hath adopted Bishop Berke- 
 ley's arguments against the existence of 
 matter, and thinks them unanswerable. 
 
 We may observe, that this great meta- 
 physician, though in general he declares in 
 favour of universal scepticism, and there- 
 fore may seem to have no first principles at 
 all, yet, with Des Cartes, he always acknow- 
 ledges the reality of those thoughts and 
 operations of mind of which we are con- 
 scious--)- So that he yields the antecedent 
 of Des Cartes's enthymeme cog'ito, but 
 denies the conclusion ergo sum, the mind 
 being, according to him, nothing but that 
 train of impressions and ideas of which we 
 are conscious. 
 
 Thus, we see that the modern philosophy, 
 of which Des Cartes may justly be ac- 
 counted the founder, being built upon the 
 ruins of the Peripatetic, has a spirit quite 
 opposite, and runs into a contrary extreme. 
 The Peripatetic not only adopted as first 
 principles those which mankind have always 
 rested upon in their most important trans- 
 actions, but, along with them, many vulgar 
 prejudices ; so that this system was founded 
 upon a wide bottom, but in many parts 
 unsound. The modern system has nar- 
 rowed the foundation so much, that every 
 superstructure raised upon it appears top- 
 heavy. 
 
 From the single principle of the exist- 
 ence of our own thoughts, very little, if any 
 thing, can be deduced by just reasoning, 
 especially if we suppose that all our other 
 faculties may be fallacious. 
 
 Accordingly, we find that Mr Hume was 
 not the first that was led into scepticism by 
 the want of first principles. For, soon after 
 Des Cartes, there arose a sect in France 
 called Egoists, who maintained that we 
 have no evidence of the existence of any- 
 thing but ourselves.^: [ 64 1 ] 
 
 Whether these egoists, like Mr Hume, 
 
 * If I rorollect arielit, (I write this nn(e a» a di?. 
 taiice from liocks,) Locke explicitly anticipates ihe 
 Berkeleiaii iileali-m in his " Kxaininatinn ot Father 
 Malebranche's Opini' n." This w.is aUo done oy 
 Bayle. In fact, Malehranch", aid many otiiers be. 
 fore him, wonid inevitably have become Idealists, 
 had they not been Catholics. But an Idealist, as I 
 have already observed, no consistent t'aitiolic could 
 be. See above, p. iSd, note t> antl P- 358, note *. 
 — H. 
 
 t See above, p. 4V9, b, not .— H. 
 
 $ See above p. i69, a, note ^ ; and p. S9'J, b, note 
 *.— H. 
 
 [639-6413
 
 CHAP. V 
 
 „.] 
 
 OPINIONS ABOUT FIRST PRINCIPLES. 
 
 465 
 
 believed themselves tobe nothing but a train 
 of ideas and impressions, or to have a more 
 permanent existence, I have not learned, 
 having never seen any of their writings ; nor 
 do I know whethei- any of this sect did write 
 in support of their principles. One would 
 think they who did not believe that there 
 was any person to read, could have little 
 inducement to write, nnless they were 
 prompted by that inward monitor which 
 Persius makes to be the source of genius 
 and the teacher of arts. There can be no 
 doubt, however, of the existence of such a 
 sect, as they are mentioned by many 
 authors, and refuted by some, particularly 
 by Buffier, in his treatise of first principles. 
 
 Those Egoists and ]Mr Hume seem to 
 me to have reasoned more consequentially 
 from Des Cartes' principle than he did him- 
 self; and, indeed, I cannot help thinking, 
 that all who have followed Des Cartes' 
 method, of requiring proof by argument of 
 everything except the existence of their 
 own thoughts, have escaped the abyss of 
 scepticism by the help of weak reasoning 
 and strong faith more than by any other 
 means. And they seem to me to act more 
 consistently, who, having rejected the first 
 principles on which belief must be grounded, 
 have no belief, than they, who, like the 
 others, rejecting first principles, must yet 
 have a system of belief, without any solid 
 foundation on which it may stand. 
 
 Tlie philosophers I have hitherto men- 
 , tioned, after the time of Des Cartes, have 
 all followed his method, in resting upon the 
 truth of their own thoughts as a first 
 principle, but requiring arguments for the 
 proof of every other truth of a contingent 
 nature ; but none of them, excepting Mr 
 Locke, has expressly treated of first princi- 
 ples, or given any opinion of their utiHty or 
 inutility. We only collect their opinion 
 from their following Des Cartes in requir- 
 ing proof, or pretending to offer proof of 
 the existence of a material world, which 
 surely ought to be received as a first princi- 
 ple, if anything be, beyond what wc are 
 conscious of. [642] 
 
 I proceed, therefore, to consider what 
 Mr Locke has said on the subject of first 
 principles or maxims, 
 
 I have not theleastdoubt of this author's 
 candour in what he somewhere says, that 
 his essay was mostly spun out of his own 
 tlioughts. Yet, it is certain, that, in many 
 of the notions which we are wont to ascribe 
 to him, others were before him, particularly 
 Dc8 Cartes, Gassendi, and Ilobbes, Nor 
 is it at all to be thought strange, that inge- 
 nious men, when they are got into the 
 fcame track, should hit upon the same 
 thi))gs. 
 
 But, in the definition which he gives of 
 knowledge in general, and in his notions 
 [(>t2, <i 1^3] 
 
 concerning axioms or first principles, I 
 know none that went before him, though 
 he has been very generally followed in both. 
 
 His definition of knowledge, that it con- 
 sists solely in the perception of the agree- 
 ment or disagreement of our ideas, has been 
 already considered. But supposing it to be 
 just, still it would be true, that some agree- 
 ments and disagreements of ideas must be 
 immediately perceived ; and such agree- 
 ments or disagreements, when they are 
 expressed by affirmative or negative propo- 
 sitions, are first principles, because their 
 truth is immediately discerned as soon as 
 they are understood. 
 
 This, I think, is granted by Mr Locke, 
 book 4, chap. 2, " There is a part of our 
 knowledge," says he, " which we may call 
 intuitive. In this the mind is at no pains 
 of proving or examining, but perceives the 
 truth as the eye does light, only by being 
 directed toward it. And this kind of know- 
 ledge is the clearest and most certain that 
 human frailty is capable of. This part of 
 knowledge is irresistible, and, like bright 
 sunshine, forces itself immediately to be 
 perceived, as soon as ever the mind turns 
 its view that way." [043] 
 
 He farther observes — " That this intui- 
 tive knowledge is necessary to connect all 
 the steps of a demonstration."* 
 
 From this, I think, it necessarily follows, 
 that, in every branch of knowledge, we 
 must make use of truths that are intuitively 
 known, in order to deduce from them such 
 as require proof. 
 
 But I cannot recoueile this w'ith what ho 
 says, § 8, of the same chapter : — " The 
 necessity of this intuitive knowledge in every 
 step of scientifical or demonstrative i-eason- 
 ing gave occasion, I imagine, to that mis- 
 taken axiom, that all reasoning wasf.r pra- 
 (•(ignilis et prcsconce.ssis, which, how far it is 
 mistaken, I shall have occasion to shew 
 more at large, when I come to consider 
 propositions, and particularly those proposi- 
 tions which are called maxims, and to shew 
 that it is by a mistake that they arc sup* 
 posed to be the foundation of all our know- 
 ledge and reasonings." 
 
 1 have carefully considered the chapter 
 on maxims, which Mr Locke hero refers to ; 
 and, though one would expect, from the 
 quotation last made, that it should run con- 
 trary to what I have before delivered con- 
 cerning first principles, I find only two or 
 three sentences in it, and those cliiefiy inci- 
 dental, to which 1 do not assent ; and I am 
 always happy in agreeing witii a jiiiiioso- 
 pher whom I 8o highly respect. 
 
 He endeavours to shew that axioms or 
 intuitive truths are not innate. -j- 
 
 ♦ See Stcwjrl'* " KlomeiitB," ii. p. 4!).— H. 
 f He ctoc'H more, lie nttcmiits to shew that Ihoy 
 are all gener.-ilizatii>ns from txperieiicc; whrrcas rx. 
 
 2 H
 
 466 
 
 ON THE INTELLECTUAL POWERS. 
 
 [kssay vj. 
 
 To this I agree, I maintain only, that 
 when the understanding is ripe, and wlien 
 we distinctly apprehend such truths, we 
 immediately assent to them. [644] 
 
 He observes, that self-evidence is not 
 peculiar to those propositions which pass 
 under the name of axioms, and have the 
 dignity of axioms ascribed to them. ' 
 
 I grant that there are innumerable self- 
 evident propositions, which have neither 
 dignity nor utility, and, therefore, deserve 
 not the name of axioms, as that name is 
 commonly understood to imply not only 
 self-evidence, but some degree of dignity or 
 utility. That a man is a man, and that a 
 man is not a horse, are self-evident propo- 
 sitions ; but they are, as Mr Locke very 
 justly calls them, trifling propositions. Til- 
 lotson very wittily says of such propositions, 
 that they are so surfeited with truth, that 
 they are good for nothing ; and as they de- 
 serve not the name of axioms, so neither 
 do they deserve the name of knowledge. 
 
 He observes, that such trifling self-evi- 
 dent propositions as we have named are not 
 derived from axioms, and therefore tliat all 
 our knowledge is not derived from axioms. 
 
 I grant that they are not derived from 
 axioms, because they are themselves self- 
 evident. But it is an abuse of words to call 
 them knowledge, as it is, to call them 
 axioms ; for no man can be said to be the 
 wiser or more knowing for having millions of 
 them in store. 
 
 He observes, that the particular propo- 
 sitions contained under a general axiom are 
 no less self-evident than the general axiom, 
 and that they are sooner known and under- 
 stood. Thus, it is as evident that my hand 
 is less than my body, as that a part is less 
 than the whole ; and I know the truth of 
 the particular proposition sooner than that 
 of the general. 
 
 This is true. A man cannot perceive the 
 truth of a general axiom, such as, that a 
 part is less than the whole, until he has the 
 general notions of a part and a whole formed 
 in his mind ; and, before he has these 
 general notions, he may perceive that his 
 hand is less than his body. [645] 
 
 A great part of this chapter on maxims 
 is levelled against a notion, which, it seems, 
 some have entertained, that all our know- 
 ledge is derived from these two maxims — 
 to wit, whatever in, is ; and it is impot^sible 
 for iNk same thing to be, and not to be.* 
 
 This I take to be a ridiculous notion, 
 justly deserving the treatment which Mr 
 
 perience on!y affords the occasions on which the 
 native (not innate) or a priori cognitions, virtually 
 possessed by the mind, actually manifest their exist- 
 ence. — H. 
 
 * These are called, the principle of Identity, and the 
 principle of Contradiction, or. more properly, Non- 
 con tradiction. — H. 
 
 Locke has given it, if it at all merited his 
 notice. These are identical propositions ; 
 they are trifling, and surfeited with truth. 
 No knowledge can be derived from them. 
 
 Having mentioned how far I agree with 
 Mr Locke concerning maxims or first prin- 
 ciples, I shall next take notice of two or 
 three things, wherein I cannot agree with 
 him. 
 
 Li the seventh section of this chapter, he 
 says. That, concerning the real existence of 
 all other beings, besides ourselves and a 
 first cause, there are no maxims. 
 
 I have endeavoured to shew that there 
 are maxims, or first principles, with regard 
 to other existences. Mr Locke acknowledges 
 that we have a knowledge of such existences, 
 which, he says, is neither intuitive nor de- 
 monstrative, and which, therefore, he calls 
 sensitive knowledge. It is demonstrable, 
 and was long ago demonstrated by Aristotle, 
 that every proposition to which we give a 
 rational assent, must either have its evi- 
 dence in itself, or derive it from some ante- 
 cedent proposition. And the same thing 
 may be said of the antecedent proposition. 
 As, therefore, we cunnot go back to ante- 
 cedent propositions without end, the evi- 
 dence must at last rest upon propositions, 
 one or more, which have their evidence in 
 themselves — that is, upon first principles. 
 
 As to the evidence of our own existence, 
 and of the existence of a first cause, Mr 
 Locke does not say whether it rests upon 
 first principles or not. But it is manifest, 
 from what he has said upon both, that it 
 does. [646] 
 
 With regard to our own existence, says 
 he, we perceive it so plainly and so cer- 
 tainly that it neither needs nor is capable 
 of any proof. This is as much as to say 
 that our own existence is a first principle ; 
 for it is applying to this truth the very 
 definition of a first principle. 
 
 He adds, that, if I doubt, that very doubt 
 makes me perceive my own existence, and 
 will not suff"er me to doubt of that. If I 
 feel pain, I have as certain perception of 
 my existence as of the pain I feel. 
 
 Here we have two first principles plainly 
 implied — First, That my feeling pain, or 
 being conscious of pain, is a certain evidence 
 of the real existence of that pain ; and, 
 seco7v!ly, That pain cannot exist without a 
 mind or being that is pained. That these 
 are first principles, and incapable of proof, 
 Mr Locke acknowledges. And it is certain, 
 that, if they are not true, we can have no 
 evidence of our own existence ; for, if we 
 may feel pain when no pain really exists, or 
 if pain may exist without any being that is 
 pained, then it is certain that our feeling 
 pain can give us no evidence of our ex- 
 istence. 
 
 Thus, it appears that the evidence of our 
 
 [644.-046^
 
 CHAP. VII.] OPINIONS ABOUT FIRST PRINCIPLES. 
 
 467 
 
 own existence, according to the view that 
 Mr Loclie gives of it, is grounded upon two 
 of those first principles which we had occa- 
 eion to mention. 
 
 If we consider the argument he has given 
 for the existence of a first intelligent cause, 
 it is no less evident that it is grounded upon 
 other two of them. The first, That what 
 begins to exist must have a cause of its ex- 
 istence ; and the second, That an unintelli- 
 gent and unthiuking being cannot be the 
 cause of beings that are thinking and in- 
 telligent. Upon these two principles, he 
 argues, very convincingly, for the existence 
 of a first intelligent cause of things. And, 
 if these principles are not true, we can have 
 no proof of the existence of a first cause, 
 either from our own existence, or from the 
 existence of other things that fall within our 
 view. [647] 
 
 Another thing advanced by Mr Locke 
 upon this subject is, that no science is or 
 hath been built upon maxims. 
 
 Surely Mr Locke was not ignorant of 
 geometry, which hath been built upon 
 maxims prefixed to the elements, as far back 
 as we are able to trace it.* But, though 
 they had not been prefixed, which was a 
 matter of utility rather than necessity, yet 
 it must be granted that every demonstra- 
 tion in geometry is grounded either upon 
 propositions formerly demonstrated, or upon 
 self-evident principles. 
 
 Mr Locke farther says, that maxims are 
 not of use to help men forward in the ad- 
 vancement of the sciences, or new dis- 
 coveries of yet unknown truths ; that New- 
 ton, in the discoveries he has made in his 
 never-enough-to-be-admired book, has not 
 been assisted by the general maxims — what- 
 ever is, is ; or, the whole is greater than a 
 part ; or the like. 
 
 [ answer, the first of these is, as was be- 
 fore observed, an identical trifiing proposi- 
 tion, of no use in mathematics, or in any 
 other science. The second is often used by 
 Newton, and by all mathematicians, and 
 many demonstrations rest upon it. In 
 general, Newton, as well as all other mathe- 
 maticians, grounds his demonstrations of 
 mathematical i)roiKisitions upon the axioms 
 laid down by Euclid, or upon propositions 
 wiiich have been before demonstrated by 
 help of those axioms. [C4f{] 
 
 But it deserves to be particularly observed, 
 that Niwton, intending, in the third book of 
 liift " Principia," to give a more scientific 
 form to the physical part of astronomy, 
 which he hud at first composed inapi)])ular 
 form, tliouglit proper to follow the exam])le 
 of Euclid, and to lay down first, in what he 
 
 * Compare Stewart's " Kkmeiits," ii. [ip, 38, i;t, 
 106. (Jii thi» sulijcct, "Batius est bjlerequain parum 
 diCiTc."— il. 
 
 [64.7-(i4.y] 
 
 calls " Rcgulcs PhHosnphandi,'" and in his 
 " Phcenomena," the first principles which he 
 assumes in his reasoning. 
 
 Nothing, therefore, could have been more 
 unluckily adduced by Mr Locke to support 
 his aversion to first principles, than the ex- 
 ample of Sir Isaac Newton, who, by laying 
 down the first principles upon which he rea- 
 sons in those parts of natural philosophy 
 which he cultivated, has given a stability to 
 that science which it never had before, and 
 which it will retain to the end of the world. 
 
 I am now to give some account of a philo- 
 sopher, who wrote expressly on the subject 
 of first principles, after Mr Locke. 
 
 Pere Buffier, a French Jesuit, first pub- 
 lished his " Traiie des premiers Veritez, el 
 de la Source de nos Jiigements^'''' in 8vo, if 
 I mistake not, in the year 1724. It was 
 afterwards published in folio, as a part of 
 his " Conrs deS' Sciences." Paris, 1732. 
 
 He defines first principles to be proposi- 
 tions so clear that they can neither be 
 proved nor combated by those that are more 
 clear. 
 
 The first source of first principles he men- 
 tions, is, that intimate conviction which 
 every man has of his own existence, and of 
 what passes in his own mind. Some philo- 
 sophers, he observes, admitted these as first 
 principles, who were unwilling to admit any 
 others ; and he shews the strange conse- 
 quences that follow from this system. 
 
 A second source of first principles he 
 makes to be common sense ; which, he ob- 
 serves, philosophers have niit been wont to 
 consider. He defines it to be the disposi- 
 tion which Nature has planted in all men, 
 or the far greater part, which leads them, 
 when they come to the use of reason, to form 
 a common and tmiform judgment upon 
 objects which are not objects of conscious- 
 ness, nor are founded on any antecedent 
 judgment- [(i4!J] 
 
 He mentions, not as a full enumeration, 
 but as a specimen, the following principles 
 of common sense. 
 
 1. That there are other beings and other 
 men in the universe, besides myself. 
 
 2. That there is in them something that 
 is called truth, wisdom, prudence; and that 
 these tilings are not purely arbitrary. 
 
 3. That there is something in me which 
 I call intelligence, and something which is 
 not that intelligence, which I call my body ; 
 and that these things have ditl'erent pro- 
 perties. 
 
 4. That all men are not in a conspiracy 
 to deceive me and impose upon my cre- 
 didity. 
 
 6. That what lias not intelligence cannot 
 produce the effects of intelligence, nor caa 
 pieces of matter tiirown together by chance 
 form any regular work, such as a clock or 
 watch. 
 
 2 II y
 
 468 
 
 ON THE INTELLECTUAL POWERS. 
 
 [essay VI. 
 
 He explains very particularly the several 
 parts of his definition of common sense, 
 and shews how the dictates of common 
 sense may be distinguished from common 
 prejudices ; and then enters into a particular 
 consideration of tlie primary truths that 
 concern being in general ; the truths that 
 concern thinking beings ; those that concern 
 body ; and those on which the various 
 branches of human knowledge are grounded. 
 I shall not enter into a detail of his sen- 
 timents on these subjects. I think there is 
 more which I take to be original in this 
 treatise than in most books of the meta- 
 physical kind I have met with ; that many 
 of his notions are solid ; and that others, 
 which I cannot altogether approve, are 
 ingenious. [G50] 
 
 The other writers I have mentioned, 
 after Des Cartes, may, I think, -without 
 impropriety, be called Cartesians, For, 
 though they differ from Des Cartes in some 
 things, and contradict him in others, yet 
 they set*out from the same principles, and 
 follow the same method, admitting no other 
 first principle with regard to the existence 
 of tilings but their own existence, and the 
 existence of those operations of mind of 
 which they are conscious, and requiring 
 that the existence of a material world, and 
 the existence of other men and things, 
 should be proved by argument. 
 
 This method of philosophising is common 
 to Des Cartes, Malebranche, Arnauld, 
 Locke, Norris, Collier, Berkeley, and Hume ; 
 and, as it was introduced by Des Cartes, I 
 call it the Cartesian system, and those who 
 follow it Cartesians, not intending any dis- 
 respect by this term, but to signify a parti- 
 cular method of philosophising common to 
 them all, and begun by Des Cartes. 
 
 Some of these have gone the utmost 
 length in scepticism, leaving no existence 
 in nature but that of ideas and impressions. 
 Some have endeavoured to throw off the 
 belief of a material world only, and to leave 
 us ideas and spirits. All of them have 
 fallen into very gross pai-adoxes, which can 
 never sit easy upon the human understand- 
 ing, and which, though adopted in the 
 closet, men find themselves under a ne- 
 cessity of throwing off and disclaiming when 
 they enter into society. 
 
 Indeed, in my judgment, those who have 
 reasoned most acutely and consequentially 
 upon this system, are they that have gone 
 deepest into scepticism. 
 
 Father Buffier, however, is no Cartesian 
 in this sense. He seems to have perceived 
 the defects of the Cartesian system while 
 it was in the meridian of its glory, and to 
 bave been aware that a ridiculous scepticism 
 is the natural issue of it, and therefore 
 nobly attempted to lay a broader founda- 
 tion for human knowledi^e, and has flic 
 
 honour of being the first, as far as I know, 
 after Aristotle, who has given the world a 
 just treatise upon first principles. [(551] 
 
 Some late writers, particularly Dr Os- 
 wald, Dr Beattie, and Dr Campbell, have 
 been led into a way of thiuking somewhat 
 similar to that of IJuffier ; the two former, 
 as I have reason to believe, without any in- 
 tercourse with one another, or any know- 
 ledge of what Buffier had wrote on the sub- 
 ject. Indeed, a man who thinks, and who 
 is acquainted with the philosophy of Mr 
 Hume, will very naturally be led to appre- 
 hend, that, to support the fabric of human 
 knowledge, some other principles are neces- 
 sary than those of Des Cartes and Mr 
 Locke. Buffier must be acknowledged to 
 have the merit of having discovered this, 
 before the consequences of the Cartesian 
 system were so fully displayed as they have 
 been by Mr Hume. But I am apt to think 
 that the man who does not see this now, 
 must have but a superficial knowledge of 
 these subjects." 
 
 The three writers above mentioned have 
 ray high esteem and affection as men ; but 
 I intend to say nothing of them as writers 
 upon this subject, that I may not incur the 
 censure of partiality. Two of them have 
 been joined so closely with me in the anim- 
 adversions of a celebrated writer,-}- that 
 we may be thought too near of kin to give 
 our testimony of one another. 
 
 CHATTER VIIL 
 
 OF PREJUDICES, THE CAUSES OF ERROU. 
 
 Our intellectual powers are wisely fitted 
 by the Author of our nature for the disco- 
 very of truth, as far as suits our present 
 state. Error is not their natural issue, any 
 more than disease is of the natural structure 
 of the body. Yet, as we are liable to vari- 
 ous diseases of body from accidental causes, 
 external and intei-nal ; so we are, from like 
 causes, liable to wrong judgments, [652] 
 
 Medical writers have endeaA'oured to enu- 
 merate the diseases of the body, and to re- 
 duce them to a system, under the name of 
 nosology ; and it were to be wished that we 
 had also a nosology of the human under- 
 standing. 
 
 When we know a disorder of the body, 
 we are often at a loss to find the proper 
 remedy ; but in most cases the disorders of 
 the understanding point out their remedies 
 so plainly, that he who knows the one must 
 know the other. 
 
 Many authors have furnished useful ma- 
 terials for this purpose, and some have en- 
 deavoured to reduce them to a system, I 
 
 * See Note A.— H. 
 
 ( Priestley.— H. 
 r 650-652 1
 
 CHAP, vin.] OF PUEJUDICES, THE CALSliS OF ERROR. 
 
 4*39 
 
 like best the general division given of them 
 by Lord Bacon, in his fifth book " De Aug- 
 inentis Scientiarum,'"' and more fully treated 
 in his " Novum Organum.'''' lie divides 
 them into four classes — ido!n Irihit.t, idola 
 specus, idola fori, and idola thealri. The 
 names are perhaps fanciful ; but I think 
 the division judicious, like most of the pro- 
 ductions of that wonderful genius. And as 
 this division was first made by him, he may 
 be indulged the privilege of giving names 
 to its several members. 
 
 I propose in this chapter to explain the 
 several members of this division, according 
 to the meaning of the author, and to give 
 instances of each, without confining myself 
 to those which Lord Bacon has given, and 
 without pretending to a complete enumera- 
 tion. 
 To every bias of the understanding, by which 
 a man may be misled in judging, or drawn 
 into error. Lord Bacon gives the name of 
 an idol. The understanding, in its natural 
 and best state, pays its homage to truth 
 only. The causes of error are considered 
 by him as so man}- false deities, who receive 
 the homage which is due only to truth. 
 1.653] 
 
 A. The first class are the idola triLus, 
 The.-e are such as beset the whole human 
 species ; so that every man is in danger 
 from them. They arise from principles of 
 the human constitution, which are highly 
 useful and necessary in our present state ; 
 but, by their excess or defect, or wrong 
 direction, may lead us into error. 
 
 As the active principles of the human 
 frame are wisely contrived by the Author 
 of our being for the direction of our ac- 
 tions, and yet, without proper regulation 
 and restraint, are apt to lead us wrong, so 
 it is also with regard to those parts of our 
 constitution that have influence upon our 
 opinions. Of this we may take the follow- 
 ing instances : — 
 
 1. First, — Men are prone to be led too 
 much by authority in their opinions. 
 
 In the first part of life, we have no other 
 guide ; and, without a disposition to receive 
 implicitly what we are taught, we should 
 be incapable of instruction, and incapable 
 of improvement. 
 
 When judgment is ripe, there are many 
 things in which we are incompetent judges. 
 In such matters, it is most reasonable to 
 rely u])on the judgment of those whom we 
 believe to be competent and disinterested. 
 The highest court of judicature in the 
 nation relies upon the autliority of lawyers 
 and jiliysicians in n)atters belonging to 
 their respective professions. 
 
 Even in matters ^vliich we have access 
 to know, authority always will have, and 
 ought to have, more or less weigiit, in ]iro- 
 portion to tlie evidence on which our own 
 [6.>3- 6.V'/| 
 
 judgment rests, and the opinion we have of 
 the judgment and candour of those who 
 differ from us, or agree with us The 
 modest man, conscious of his own fal- 
 libility in judging, is in danger of giving 
 too much to authority ; the arrogant of 
 giving too little. [654] 
 
 In all matters belonging to our cog- 
 nizance, every man must be determined by 
 his own final judgment, otherwise he does 
 not act the part of a rational being. 
 Authority may add weight to one scale ; 
 but the man holds the balance, and judges 
 what weight he ought to allow to authority. 
 
 If a man should even claun infallibility, 
 we must judge of his title to that preroga- 
 tive. If a man pretend to be an ambassa- 
 dor from heaven, we must judge of his 
 credentials. No claim can deprive us of 
 this right, or excuse us for neglecting to 
 exercise it. 
 
 As, therefore, our regard to authority 
 may be either too great or too small, the 
 bias of human nature seems to lean to the 
 first of these extremes ; and I believe it is 
 good for men in general that it should do so. 
 
 When this bias concurs with an iudifi'er- 
 ence about truth, its operation will be the 
 more powerful. 
 
 The love of truth is natural to man, and 
 strong in every well-disposed mind. But 
 it may be overborne by party zeal, by 
 vanity, by the desire of victory, or even by 
 laziness. When it is superior to these, it 
 is a manly virtue, and requires the exer- 
 cise of industry, fortitude, self-denial, can- 
 dour, and openness to conviction. 
 
 As there are persons in the world of so 
 mean and abject a spirit that they rather 
 clioose to owe their subsistence to the 
 charity of others, tlian by industry to ac- 
 quire some jiroperty of their own ; so there 
 are many more who may be called mere 
 beggars with regard to their opinions. 
 Through laziness and iiidift'erence about 
 truth, they leave to others the drudgery of 
 digging fortius eonunodity ; they can have 
 enougli at second hand to serve their occa- 
 sions. Their concern is not to know what 
 is true, but what is said and thought on 
 such subjects ; and their understanding, 
 like their clothes, is cut according to the 
 fashion. [655] 
 
 This distemper of the understanding has 
 taken so deep root in a great j)art of man- 
 kind, that it can hardly be said that they 
 use their own judgment in things that do 
 not concern their temporal interest. Nor is 
 it jicculiar to the ignorant ; it infects all 
 ranks. We may guess their opinions when 
 we know where they wire born, of what 
 parents, how educated, and what company 
 they have ke]if. These circuniHlani-cK de- 
 termine (lieiropinioiisin religion, in politics. 
 and in pliilosojihy.
 
 470 
 
 ON THE INTELLECTUAL POWERS. 
 
 [_KSSAY VI. 
 
 2. A second general prejudice arises from 
 a dispodtion to measure things less known 
 and less familiar, by those that are hct'.er 
 known and more familiar. 
 
 This is tlie foundation of analogical rea- 
 soning, to which we have a great proneness 
 by nature, and to it indeed we owe a great 
 part of our knowledge. It would be absurd 
 to lay aside this kind of reasoningal together, 
 and it is difficult to judge how far we may 
 venture upon it. The bias of human nature 
 is to judge from too slight analogies. 
 
 Tlie objects of sense engross our thoughts 
 m the first part of life, and are most fami- 
 liar through the whole of it. Hence, in all 
 ages men have been prone to attribute the 
 human figure and human passions and frail- 
 ties to superior intelligences, and even to 
 the Supreme Being. 
 
 There is a disposition in men to mate- 
 rialize everything, if I may be allowed the 
 expression ; that is, to apply the notions we 
 have of material objects to things of another 
 nature. Thought is considered as analogous 
 to motion in a body ; and as bodies are put 
 in motion by impulses, and by impressions 
 made upon them by contiguous objects, we 
 are apt to conclude that the mind is made 
 to think by impressions made upon it, and 
 that there must be some kind of contiguity 
 between it and the objects of thought. 
 Hence the theories of ideas and impressions 
 have so generally prevailed. [656] 
 
 Because the most perfect works of human 
 artists are made after a model, and of ma- 
 terials that before existed, the ancient phi- 
 losophers universally believed that the world 
 was made of a pre ■ existen t uncreated matter ; 
 and many of them, that there were eternal 
 and uncreated models of every species of 
 things which God made. 
 
 The mistakes in common life, which are 
 owing to this prejudice, are innumerable, 
 and cannot escape the slightest observation. 
 Men judge of other men by themselves, or 
 by the small circle of their acquaintance. 
 The selfish man thinks all pretences to be- 
 nevolence and public spirit to be mere 
 hypocrisy or self-deceit. The generous and 
 open-hearted believe fair pretences too 
 easily, and are apt to think men better than 
 they really are. The abandoned and pro- 
 fligate can hardly be persuaded that there 
 is any such thing as real virtue in the world. 
 The rustic forms his notions of the man- 
 ners and characters of men from those of 
 his country village, and is easily duped when 
 he comes into a great city. 
 
 It is commonly taken for granted, that 
 this narrow way of judging of men is to be 
 cured only bj' an extensive intercourse with 
 men of different ranks, professions, and 
 nations ; and that the man whose acquaint- 
 ance has been confined within a narrow 
 'ircle, must have many prejudices and nar- 
 
 row notions, which a more extensive inter- 
 course would have, cured. 
 
 3. Men are often led into error by the 
 love of simplicity, tuhivh disposes us to re- 
 duce things to few principles, and to con- 
 ceive a greater simplicity in natuie than 
 there really is.* [657] 
 
 To love simplicity, and to be pleased with 
 it wherever we find it, is no imperfection, 
 but the contrary. It is the result of good 
 taste. We cannot but be pleased to ob- 
 serve, that all the changes of motion pro- 
 duced by the collision of bodies, hard, soft, 
 or elastic, are reducible to three simple 
 laws of motion, which the industry of phi- 
 losophers has discovered. 
 
 When we consider what a prodigious 
 variety of effects depend upon the law of 
 gravitation ; how many phpenomena in the 
 earth, sea, and air, which, in all preceding 
 ages, had tortured the wits of philosophers, 
 and occasioned a thousand vain theories, 
 are shewn to be the necessary consequences 
 of this one law ; how the whole system of 
 sun, moon, planets, primary and secondary, 
 and comets, are kept in order by it, and 
 their seeming irregularities accounted for 
 and reduced to accurate measure — the sim- 
 plicity of the cause, and the beauty and 
 variety of the effects, must give pleasure to 
 every contemplative mind. By this noble 
 discovery, we are taken, as it were, behind 
 the scene in this great drama of nature, 
 and made to behold some part of the art of 
 the divine Author of this system, which, 
 before this discovery, eye had not seen, nor 
 ear heard, nor had it entered into the heart 
 of man to conceive. 
 
 There is, without doubt, in every work 
 of nature, all the beautiful simplicity that is 
 consistent with the end for which it was 
 made. But, if we hope to discover how 
 nature brings about its ends, merely from 
 this principle, that it operates in the simplest 
 and best way, we deceive ourselves, and 
 forget that the wisdom of nature is more 
 above the wisdom of man, than man's wis- 
 dom is above that of a child. 
 
 If a child should sit down to contrive how 
 a city is to be fortified, or an army arranged 
 in the day of battle, he would, no doubt, 
 conjecture what, to his understanding, ap- 
 peared the simplest and best way. But 
 could he ever hit upon the true way ? No 
 surely. When he learns from fact how 
 these effects are produced, he will then see 
 how foolish his childish conjectures were. 
 [658] 
 
 We may learn something of the way in 
 which nature operates from fact and ob- 
 servation ; but, if we conclude that it ope- 
 rates in such a manner, only because to our 
 
 * See" Inquiry," cb. vii. ^ 3, above, \\ 206, sqq 
 -H. 
 
 [656-658]
 
 CHAP. VIII.] OF PREJUDICES, THE CAUSES OF ERROR. 
 
 471 
 
 understandmg that appears to be the best 
 and simplest mauuer, we shall always go 
 wrong. 
 
 It was believed, for many ages, that all 
 the variety of concrete bodies we find on 
 this globe is reducible to four elements, of 
 which they are compounded, and into which 
 they may be resolved. It was the simpli- 
 city of this theory, and not any evidence 
 from fact, that made it to be so generally 
 received ; for the more it is examined, we 
 find the less ground to believe it. 
 
 The Pythagoreans and Platonists were 
 carried farther by the same love of sim- 
 plicity. Pythagoras, by his skill in mathe- 
 matics, discovered, that there can be no 
 more than five regular solid figures, ter- 
 minated by plain surfaces, which are all 
 similar and equal ; to wit, the tetrahedron, 
 the cube, the octahedron, the dodecahedron, 
 and the eicosihedron. As nature works in 
 the most simple and regular way, he thought 
 that all the elementary bodies must have 
 one or other of those regular figures ; and 
 that the discovery of the properties and 
 relations of the regular solids would be a 
 key to open the mysteries of nature. 
 
 This notion of the Pythagoreans and 
 Platonists has undoubtedly great beauty 
 and simplicity. Accordingly it prevailed, 
 at least, to the time of Euclid. He was 
 a Platonic philosopher, and is said to have 
 wrote all the books of his " Elements" in 
 order to discover the properties and rela- 
 tions of the five rejjular solids. This ancient 
 tradition of the intention of Euclid in writing 
 bis " Elements," is countenanced by the 
 work itself. For the last books of the 
 " Elements" treat of the regular solids, and 
 all the preceding are subservient to the 
 last. [659] 
 
 So that this most ancient mathematical 
 work, which, for its admirable composition, 
 has served as a model to all succeeding 
 writers in mathematics, seems, like the two 
 first books of Newton's "Principia," to 
 have been intended by its author to exhibit 
 the mathematical principles of natural phi- 
 sophy. 
 
 It was long believed, that all the qualities 
 of bodies," and all their medical virtues, 
 were reducible to four — moisture and dry- 
 ness, heat and cold ; and that there are 
 only four temperaments of the human body — 
 the sanguine, the melancholy, the bilious, 
 and the phlegmatic. The chemical system, 
 of reducing all bodies to salt, sulphur, and 
 mercury, was of the same kind. For liow 
 many ages did men believe, that the division 
 of all the objects of thought into ten cate- 
 gories, and of ail that can be affirmed or 
 denied of anything, into five universals or 
 predicables, were perfect enumerations ? 
 
 "7 Only the qualilakt prima; of the Peripatetio.— 
 
 The evidence from reason that could be 
 produced for those systems was next to no- 
 thing, and bore no proportion to the ground 
 they gained in the belief of men ; but they 
 were simple and regular, and reduced things 
 to a few principles ; and this supplied their 
 want of evidence. 
 
 Of all the systems we know, that of Des 
 Cartes was most remarkable for its sim- 
 plicity." Upon one proposition, / think, 
 he builds the whole fabric of human know- 
 ledge. And from mere matter, with a 
 certain quantity of motion given it at first, 
 he accounts for all the phsenomena of the 
 material world. 
 
 The physical part of this system was 
 mere hypothesis. It had nothing to re- 
 commend it but its simplicity ; yet it had 
 force enough to overturn the system of 
 Aristotle, after that system had prevailed 
 for more than a thousand years. 
 
 The principle of gravitation, and other 
 attracting and repelling forces, after Sir 
 Isaac Newton had given the strongest evi- 
 dence of their real existence in nature, were 
 rejected by the greatest part of Europe for 
 half a century, because they could not be 
 accounted for by matter and motion. So 
 much were men enamoured with the sim- 
 plicity of the Cartesian system. [060] 
 
 Nay, I apprehend, it was this love of 
 simplicity, more than real evidence, that led 
 Newton himself to say, in the preface to his 
 " Principia," speaking of the phtenomena 
 of the material world — " Nam multa me 
 movent ut nonnihil suspicer, ea omnia ex 
 viribus quibusdam pendere posse, quibus 
 corjiorum particulfE, per causas nondum 
 cognitas, vel in se mutuo impelluntur, et 
 secundum figuras regulares cohtierent, vel 
 ab invicem fugantur et recedunt." For 
 certainly we have no evidence from fact, 
 that all the phoDnomena of the material 
 world are produced by attracting or repell- 
 ing forces. 
 
 With iiis usual modesty, he proposes it 
 only as a slight suspicion ; and the ground 
 of this suspicion could only be, that he saw 
 that many of the phajnoraena of nature de- 
 pended upon causes of this kind ; and there- 
 fore was disposed, from the simplicity of 
 nature, to think that all do. 
 
 When a real cause is discovered, the 
 same love of simplicity leads men to attri- 
 bute efiects to it which are beyond its pro- 
 vince. 
 
 A medicine that is found to be of great 
 use in one distemper, commonly has its 
 virtues muUi])lif(l, till it boconu^s a panacea. 
 Those who have lived long, can recollect 
 many instances of this. In other branches 
 of knowledge, the same thing often happens. 
 When the attention of men is turned to any 
 
 * Sec above, p. WOfi, li, nolo (.— II,
 
 472 
 
 ON THE INTELLECTUAL POVyERS. 
 
 [^ESSAY 
 
 particular cause, by discovering it to have 
 i-emarkable effects, they are in great danger 
 of extending its influence, upon sHght evi- 
 dence, to things with which it has no con- 
 nection. Such prejudices arise from the 
 natural desire of simplifying natural causes, 
 and of accounting for many phsenomena 
 from the same principle. [061] 
 
 4. One of the most copious sources of 
 error in philosophy is the misapplication of 
 our noblest inte//ectual power to purposes for 
 which it is incompetnit. 
 
 Of all the intellectual powers of man, 
 that of invrnliiin bears the highest price. 
 It resembles most the power of creation, 
 and is honoured with that name. 
 
 We admire the man who shews a supe- 
 riority in the talent of finding the means of 
 accomplishing an end ; who can, by a happy 
 combination, produce an effect, or make a 
 discovery beyond the reach of other men ; 
 who can draw important conclusions from 
 circumstances that commonly pass unob- 
 served ; who judges with the greatest saga- 
 city of the designs of other men, and the 
 consequences of his own actions. To this 
 superiority of luiderstanding we give the 
 name of genius, and look up with admira- 
 tion to everything that bears the marks of it. 
 
 Yet this power, so highly valuable in it- 
 self, and so useful in the conduct of life, 
 may be misapplied ; and men of genius, in 
 all ages, have been prone to apply it to pur- 
 poses for which it is altogether incompe- 
 tent. 
 
 The works of men and the works of 
 Nature are not of the same order. The 
 force of genius may enable a man perfectly 
 to comprehend the former, and see them to 
 the bottom. What is contrived and exe- 
 cuted by one man may be perfectly under- 
 stood by another man. With great proba- 
 bility, he may from a part conjecture the 
 whole, or from the effects may conjecture 
 the causes ; because they are effects of a 
 wisdom not superior to his own. [662] 
 
 But the works of Nature are contrived 
 and executed by a wisdom and power in- 
 finitely superior to that of man ; and when 
 men attempt, by the force of genius, to dis- 
 cover the causes of the phaenomena of Na- 
 ture, they have only the chance of going 
 wrong more ingeniously. Their conjectures 
 may appear very probable to beings no 
 wiser than themselves ; but they have no 
 chance to hit the truth. They are like the 
 conjectures of a child how a ship of war is 
 built, and how it is managed at sea. 
 
 Let the man of genius try to make an 
 animal, even the meanest ; to make a plant, 
 or even a single leaf of a plant, or a feather 
 of a bird; he will find that all his wisdom 
 a id sagacity can bear no comparison with 
 the wisdom of Nature, nor his power with 
 the power of Nature. 
 
 The experience of all ages shews how 
 prone ingenious men have been to invent 
 hypotheses to explain the phtenomena of 
 Nature ; how fond, by a kind of anticipa- 
 tion, to discover her secrets. Instead of a 
 slow and gradual ascent in the scale of na- 
 tural causes, by a just and copious induc- 
 tion, they would shorten the work, and, by 
 a flight of genius, get to the top at once. 
 This gratifies the pride of human under- 
 standing ; but it is an attempt beyond our 
 force, like that of Phaeton to guide the 
 chariot of the sun- 
 When a man has laid out all his Inge- 
 nuity in fabricating a system, he views it 
 with the eye of a parent ; he strains phae- 
 nomena to make them tally with it, and 
 make it look like the work of Nature. 
 
 The slow and patient method of induc- 
 tion, the only way to attain any knowledge 
 of Nature's work, was little understood 
 until it was delineated by Lord Bacon, and 
 has been little followed since. It humbles 
 the pride of man, and puts him constantly in 
 mind that his most ingenious conjectures 
 with regard to the works of God are pitiful 
 and childish. [663] 
 
 There is no room here for the favourite 
 talent of invention. In the humble method 
 of information, from the great volume of 
 Nature we must receive all our knowledge 
 of Nature. Whatever is beyond a just in- 
 terpretation of that volume is the work of 
 man ; and the work of God ought not to be 
 contaminated by any mixture with it. 
 
 To a man of genius, self-denial is a diffi- 
 cult lesson in philosophy as well as in reli- 
 gion. To bring his fine imaginations and 
 most ingenious conjectures to the fiery trial 
 of experiment and induction, by which the 
 greater part, if not the whole, will be 
 found to be dross, is a humiliating task. 
 This is to condemn him to dig in a mine, 
 when he would fly with the wings of an 
 eagle. 
 
 In all the fine arts, whose end is to 
 please, genius is deservedly supreme. In 
 the conduct of human affairs, it often does 
 wonders ; but in all inquiries into the con- 
 stitution of Nature, it mu.->t act a subor- 
 dinate part, ill-suited to the superiority it 
 boasts. It may combinf, but it must not 
 fabricate. It may collect evidence, but 
 must not supply the want of it by conjec- 
 ture. It may display its powers by putting 
 Nature to the question in well-contrived 
 experiments, but it must add nothing to her 
 answers. 
 
 5. In avoiding one extreme, men are very 
 apt to rush into the opposite. 
 
 Thus, in rude ages, men, unaccustomed 
 to search for natural caus«.'s, ascribe every 
 uncommon appearance to the immediate 
 interposition of invisible beings; but wlien 
 philosophy has discovered natural causes of 
 
 [661-fiG3j
 
 CHAP VIII.] OF PREJUDICES, THE CAUSES OF ERROR. 
 
 473 
 
 many events, wliieh, in the days of ignor- 
 ance, were ascribed to the immediate opera- 
 tion of gods or dtemons, they are apt to 
 think tliat all the phsenomena of Nature 
 may be accounted for in the same way. and 
 that there is no need of an invisible Maker 
 and Governor of the world. [CG4] 
 
 Rude men are, at first, disposed to ascribe 
 inte'.Ugence and active power to everything 
 they see move or undergo any change. 
 " Savages," says the Abbe Raynal, " wlierc- 
 ever they see motion which they cannot 
 account for, there they suppose a soul." 
 When they come to be convinced of the 
 folly of this extreme, they are apt to run 
 into the opposite, and to think that every 
 thing moves only as it is moved, and acts 
 as it is acted upon. 
 
 Thus, from the e.vtreme of superstition, 
 the transition is easy to that of atheism ; 
 and from the extreme of ascribing activity 
 to every part of Nature, to that of exclud- 
 ing it altogether, and making even the deter- 
 minations of intelligent beings, the links of 
 one fatal chain, or the wheels of one great 
 machine. 
 
 The abuse of occult qualities in the Peri- 
 patetic philosophy led Des Cartes and his 
 followers to reject all occult qualities, to 
 pretend to explain all the pliEenomena of 
 Nature by mere matter and motion, and 
 even to fix disgrace upon the name of occult 
 quality. 
 
 6. Men's judgments are often perverted 
 Dy their affections and passions. This is 
 60 commonly observed, and so universally 
 acknowledged, that it needs no proof nor 
 illustration. 
 
 B. The second class of idols in Lord 
 Bacon's division are the idola specus. 
 
 These are piejudices which have their 
 origin, «■ t from the constitution of human 
 nature, but from something peculiar to the 
 indiridufil. 
 
 As in a cave objects vary in tlieir appear- 
 ance according to the form of the cave and 
 the manner in which it receives the light. 
 Lord Bacon conceives tlie mind of every 
 man to resemble a cave, which has its par- 
 ticular form, and its particular manner of 
 being enli;ihtened ; and, from these circum- 
 stances, often gives false colours and a delu- 
 sive appearance to objects seen in it." [<j().')] 
 
 For this'rea.sdn he gives the name nil lala 
 sjiccus to those i)rejudices which arise from 
 the particular way in which a man has been 
 trained, from his being addicted to some 
 particular profession, or from something 
 particular in the turn of his mind. 
 
 A man whose thoughts have been con- 
 
 * If Hacon tor.k- his siinik-of the cave. from I'latn, 
 lie hae inrnTlcd ii <r<)in its projKr infaninK; for, in 
 ttio I'laloirn 8i(?iiificatii.n, Hie- iiinUi t/iiruf ihi iild 
 (Ic-notc the ijri jiidiccsol (lie bpi-ciu, and not ol ilie 
 individual — Ihat in, oxpre'S what Bacon dmoininalcs 
 hy uloUi trthiif II. 
 
 fined to a certain track by his profession or 
 manner of life, is very apt to judge wrong 
 when he ventures out of that track. He is 
 apt to draw everything within the sphere of 
 his profession, and to judge by its maxims 
 of things that have no relation to it. 
 
 The mere mathematician is apt to apply 
 measure and calculation to things which do 
 not admit of it. Direct and inverse ratios 
 have been applied by an ingenious author to 
 measure human affections, and the moral 
 worth of actions. An eminent mathemati- 
 cian* attempted to ascertain by calculation 
 the ratio in which the evidence of facts 
 must decrease in the course of time, and 
 fixed the period when the evidence of the 
 facts on winch Christianity is founded shall 
 become evanescent, and when in conse- 
 quence no faith shall be found on the earth. 
 1 have seen a philosophical dissertation, 
 published by a very good mathematician, 
 wherein, in opposition to the ancient divi- 
 sion of things into ten categories, he main- 
 tains that there are no more, and can be no 
 more than two categories, to wit, data and 
 q'liBsita.-Y 
 
 The ancient chemists were wont to ex- 
 plain all the mysteries of Nature, and even 
 of religion, by salt, sulphur, and mercury. 
 
 Mr Locke, I think, mentions an eminent 
 musician, who believed that God created 
 the world in six days, and rested the se- 
 venth, because there are but seven notes in 
 music. I knew one of that profession, who 
 thouglit that there could be only three parts 
 in harmony — to wit, bass, tenor, and treble 
 — because there are but three persons in the 
 Trinity. [GGG] 
 
 The learned and ingenious Dr Henry 
 More liaving very elaborately and methodi- 
 cally compiled his " Enchiridium Mrtophi/- 
 tticum," and " Enchiridiutu Ethicum," 
 found all the divisions and subdivisions of 
 both to be allegorically taught in the first 
 chapter of Genesis. Thus even very inge- 
 nious men are apt to make a ridiculous 
 figure, by drawing into the track in which 
 their thoughts have long run, things alto- 
 gether foreign to it. J 
 
 Different persons, either from temper or 
 from education, have difterent tendencies of 
 understanding, which, by their excess, are 
 unfavourable to sound judgment. 
 
 Some have an undue admiration of anti- 
 (juity, and contempt of whatever is modern ; 
 others go as far into the contrary extreme. 
 It niay be judged, that the former are per- 
 
 * Craig.— H. 
 
 t Rcid refers to hi» uncle, Jamc* Gregory. Profes. 
 sorof Mathematics in St Andrew'* and Kdiiiburtjh. 
 See al)Ove, p. (if, b. . — H. 
 ■^ " Musicians ihii)k our souls are harmonics ; 
 rhysieiiuis hold that (hev complexions l)C 
 Kpii'iires make them swarms ol aioinies, 
 W liich do by charne into the body tlco. 
 Sir John Dories, in the fimt and seeond linti, al 
 liiden to Ari.loxeiiuf and (.alin— II.
 
 471 
 
 ON THE INTELLECTUAL I'OWKKS. 
 
 [essay VI. 
 
 sons who value themselves upon their ac- 
 quaintance with ancient authors, and the 
 latter such as have little knowledge of this 
 kind. 
 
 Some are afraid to venture a step out of the 
 beaten track, and think it safest to go with 
 the multitude ; others are fond of singulari- 
 ties, and of everything that has the air of 
 paradox. 
 
 Some are desultory and changeable in 
 their opinions ; others unduly tenacious. 
 Most men have a predilection for the tenets 
 of their sect or party, and still more for 
 their own inventions. 
 
 C. The idolafari are the fallacies arising 
 from the imperfections and the abuse of lan- 
 guage, which is an instrument of thought 
 as well as of the coumiunication of our 
 thoughts. [667] 
 
 Whether it be the effect of constitution 
 or of habit, I will not take upon me to de- 
 termine ; but, from one or both of these 
 causes, it happens that no man can pursue 
 a train of thought or reasoning without the 
 use of language. Words are the signs of 
 our thoughts ; and the sign is so associated 
 with the thing signified, that the last can 
 hardly present itself to the imagination, 
 without drawing the other along with it. 
 
 A man who would compose in any lan- 
 guage must think in that language. If he 
 thinks in one language what he would ex- 
 press in another, he thereby doubles his 
 labour ; and, after all, his expressions will 
 have more the air of a translation than of 
 an original. 
 
 This shews that our thoughts take their 
 colour in some degree from the language 
 we use ; and that, although language ought 
 always to be subservient to thought, yet 
 thought must be, at some times and in some 
 degree, subservient to language. 
 
 As a serv ant that is extremely useful and 
 necessary to his master, by degrees acquires 
 an authority over him, so that the master 
 must often yield to the servant, such is the 
 case with regard to language. Its inten- 
 tion is to be a servant to the understanding ; 
 but it is so useful and so necessary that we 
 cannot avoid being sometimes led by it when 
 it ought to follow. We cannot shake off 
 this impediment — we must drag it along 
 with us ; and, therefore, must direct our 
 course, and regulate our pace, as it permits. 
 Language must have many imperfections 
 when applied to philosophy, because it was 
 not made for that use. In the early periods 
 of society, rude and ignorant men use cer- 
 tain forms of speech, to express their wants, 
 their desires, and their transactions with 
 one another. Their language can reach no 
 farther than their speculations and notions ; 
 and, if their notions be vague and ill-defined, 
 the words by which they express them must 
 be so likewise. 
 
 It was a grand and noble project of 
 Bishop Wilkins* to invent a philosophical 
 language, which should be free from the 
 imperfections of vulgar languages. Whether 
 this attempt will ever succeed, so far as to 
 be generally useful, I shall not pretend to 
 determine. The great pains taken by that 
 excellent man in this design have hitherto 
 produced no effect. Very few have ever 
 entered mirmtely into his views ; far less 
 have his philosophical language and his real 
 character been brought into use. [668] 
 
 He founds his philosophical language and 
 real character upon a systematical division 
 and subdivision of all the things which may 
 be expressed by language ; and, instead of 
 the ancient division into ten categories, has 
 made forty categories, or summa genera. 
 But whether ihis division, though made by 
 a very comprehensive mind, will always suit 
 the various systems that may be introduced, 
 and all the real improvements that may be 
 made in human knowledge, may be doubted. 
 The difficulty is still greater in the sub- 
 divisions ; so that it is to be feared that 
 this noble attempt of a great genius will 
 prove abortive, imtil philosophers have the 
 same opinions and the same systems in the 
 various branches of human knowledge. 
 
 There is more reason to hope that the 
 languages used by philosophers may be 
 gradually improved in copiousness and in 
 distinctness ; and that improvements in 
 knowledge and in language may go hand in 
 hand and facilitate each other. But I fear 
 the imperfections of language can never be 
 perfectly remedied while our knowledge '.is 
 imperfect. 
 
 However this may be, it is evident that 
 the imperfections of language, and much 
 more the abuse of it, are the occasion of 
 many errors ; and that in many disputes 
 which have engaged learned men, the differ- 
 ence has been partly, and in some wholly, 
 about the meaning of words, 
 
 Mr Locke found it necessary to employ a 
 fourth part of his " Essay on Human Un- 
 derstanding" about words, their various 
 kinds, their imperfection and abuse, and 
 the remedies of both ; and has made many 
 observations upon these subjects well worthy 
 of attentive perusal. [669] 
 
 D. The fourth class of prejudices are the 
 idola theatri, by which are meajXit .prejudices 
 arising from the systems or sects in which 
 we have been trained, or which we have 
 adopted. 
 
 A false system once fixed in the mind, 
 becomes, as it were, the medium through 
 which we see objects : they receive a tinc- 
 ture from it, and appear of another colour 
 than when seen by a pure light. 
 
 Upon the same subject, a Platonist, a 
 
 * 5ee above, p. 403, note.— H. 
 
 [667- 
 
 m9
 
 CHAP. VIII.] OF PREJUDICES, THE CAUSES OF ERROR. 
 
 475 
 
 Peripatetic, and an Epicurean, will think 
 differently, not only in matters connected 
 with his peculiar tenets, but even in things 
 remote from them. 
 
 A judicious history of the different sects 
 of philosophers, and the different methods of 
 philosophisini;, which have obtained among 
 mankind, would be of no small use to direct 
 men in the search of truth. In such a 
 history, what would be of the greatest mo- 
 ment is not so much a minute detail of the 
 dogmati of each sect, as a just delineation 
 of the spirit of the sect, and of that point 
 of view in which things appeared to its 
 founder. This was perfectly understood, 
 aud, as far as concerns the theories of mo- 
 rals, is executed with great judgment and 
 candour by Dr Smith in his theory of moral 
 sentiments. 
 
 As there are certaic temperaments of the 
 body that dispose a man more to one class 
 of diseases than to another, and, on the 
 
 other hand, diseases of that kind, when they 
 happen by accident, are apt to induce the 
 temperament that is suited to them — there 
 is something analogous to this in the dis- 
 eases of the understanding. [G70] 
 
 A certain complexion of understandina 
 may dispose a man to one system ot opmions 
 more than to another ; and, on the other 
 hand, a system of opinions, fixed in the mind 
 by education or otherwise, gives that com- 
 plexion to the understanding which is suited 
 to them. 
 
 It were to be wished, that the different 
 systems that have prevailed could be classed 
 according to their spirit, as well as named 
 from their founders. Lord Bacon has dis- 
 tinguished false philosophy into the sophis- 
 tical, the empirical, and the superstitious, 
 and has made judicious observations upon 
 each of these kinds. But I apprehend thissub- 
 ject deserves to be treated more fully by such 
 a hand, if such a hand can be found. [671] 
 
 ESSAY VII. 
 
 OF REASONING. 
 
 CHAPTER I. 
 
 OF REASONINU I\' GENERAL, AND OF 
 DEMONSTRATION. 
 
 The power of reasoning is very nearly 
 allied to that of judging ; and it is of little 
 conseiiuencc in the common affairs of life 
 to distinguish them nicely. On this account, 
 the same name is often given to both. We 
 include both under the name of reason.* 
 The assent we give to a proposition is called 
 judgment, whether the proposition be self- 
 evident, or derive its evidence by reasoning 
 from other propositions. 
 
 Yet there is a distuiction between rea- 
 soning and judging. Reasoning is the pro- 
 cess by which we pass from one judgment 
 to another, which is the consequence of it. 
 Accordingly our judgments are distinguished 
 into intuitive, which arc not grounded upon 
 any preceding judgment, and discursive, 
 which are deduced from some preceding 
 judgment by reasoning. 
 
 In all reasoning, therefore, there must be 
 a proposition inferred, and one or more from 
 which it is inferred. And this power of 
 inferring, or drawing a conclusion, Ls only 
 another name for rea.soning ; the proposi- 
 tion inferred being called the conclusion, 
 
 * Kee Stewart"! " Elements," ii. p. \'i H. 
 
 [670 fi72] 
 
 and the proposition or propositions from 
 which it is inferred, the premises. [672] 
 
 Reasoning may consist of many steps ; 
 the first conclusion being a premise to a 
 second, that to a third, and so on, till we 
 come to the last conclusion. A process 
 consisting of many steps of this kind, is so 
 easily distinguished from judgment, that it 
 is never called by that name. But when 
 there is only .a single step to the conclusion, 
 the distuiction is less obvious, and the pro- 
 cess is sometimes called judgment, some- 
 times reasoning. 
 
 It is not strange that, in common dis- 
 course, judgment and reasoning should not 
 be very nicely distinguished, since they are 
 in some cases confounded even by logicians. 
 We are taught in logic, that judgment is 
 expressed by one proposition, but that rea- 
 soning requires two or three. But so 
 various are the modes of speech, that what 
 in one mode is expressed b}' two or three 
 propositions, may, in another mode, be ex- 
 pressed by one. Thus I maj' say, God is 
 (loofl ; tkerpfiire good men skatl he liaiipy. 
 This is reasoning, of that kind which logi. 
 cians call an cntliynicme, consisting of an 
 antecedent ])r()posi(ion, and a conclusion 
 drawn from it.* IJut this reasoning may 
 
 * Theenthymeiueisa mere .il)l)rvviation of expres- 
 sion; in the mental process there is no elll|i8l». IV
 
 476 
 
 ON THE INTELLECTUAL POWERS. 
 
 [^ESSAY VXl. 
 
 be expressed by one proposition, thus : — 
 Because Gnd is good, good men shall be 
 happy. This is what they call a causal 
 proposition, and therefore expresses judg- 
 ment ; yet the enthynieme, which is reason- 
 ing, expresses no more. 
 
 Reasoning, as well as judgment, must be 
 true or false : both are grounded upon evi- 
 dence which may be probable or demonstra- 
 tive, and both are accompanied with assent 
 or belief. [673] 
 
 The power of reasoning is justly accounted 
 one of the prerogatives of human nature ; 
 because by it many important truths have 
 been and may be discovered, which with- 
 out it would be beyond our reach ; yet it 
 seems to be only a kind of crutch to a 
 limited understanding. We can conceive 
 an understanding, superior to human, to 
 which that truth appears intuitively, which 
 we can only discover by reasoning. For 
 this cause, though we must ascribe judg- 
 ment to the Almighty, we do not ascribe 
 reasoning to him, because it implies some 
 defect or limitation of understanding. Even 
 among men, to use reasoning in things that 
 are self-evident, is trifling ; like a man 
 going upon crutches when he can walk 
 upon his legs. 
 
 What reasoning is, can be understood 
 only by a man who has reasoned, and who 
 is capable of reflecting upon this operation 
 of his own mind. We can define it only by 
 synonymous words or phrases, such as in- 
 ferring, drawing a conclusion, and the like. 
 The very notion of reasoning, therefore, can 
 enter into the mind by no other channel 
 than that of reflecting upon the operation 
 of reasoning in our own minds ; and the 
 notions of premises and conclusion, of a 
 syllogism and all its constituent parts, of 
 an enthymeme, sorites, demonstration, pa- 
 ralogism, and many others, have the same 
 origin. 
 
 It is nature, undoubtedly, that gives us 
 the capacity of reasoning. When this is 
 wanting, no art nor education can supply it. 
 But this capacity may be dormant through 
 life, like the seed of a plant, which, for want 
 of heat and moisture, never vegetates. This 
 is probably the case of some savages. 
 
 Although the capacity be purely the gift 
 of nature, and probably given in very dif- 
 ferent degrees to diff"erent persons ; yet the 
 power of reasoning seems to be got by habit, 
 as much as the power of walking or running. 
 Its first exertions we are not able to recol- 
 lect iu ourselves, or clearly to discern in 
 others. They are very feeble, and need to 
 be led by example, and supported by autho- 
 rity. By degrees it acquires strength, 
 chiefly by means of imitation and exer- 
 c ise. [C74] 
 
 enthymeme, Aristotle aleo meant something very dif- 
 ferent from what is vulgarly supposed.- H. 
 
 The exercise of reasoning on various sub- 
 jects not only strengthens the faculty, but 
 furnishes the mind with a store of materials. 
 Every train of reasoning, which is familiar, 
 becomes a beaten track in the way to many 
 others. It removes many obstacles which 
 lay in our way, and smooths many roads 
 which we may have occasion to travel in 
 future disquisitions. 
 
 When men of equal natural parts apply 
 their reasoning power to any subject, the 
 man who has reasoned much on the same 
 or on similar subjects, has a like advantage 
 over him who has not, as the mechanic 
 who has store of tools for his work, has of 
 him who has his tools to make, or even to 
 invent. 
 
 In a train of reasoning, the evidence of 
 every step, where nothing is left to be sup- 
 plied by the reader or hearer, must be im- 
 mediately discernible to every man of ripe 
 understanding who has a distinct compre- 
 hension of the premises and conclusion, and 
 who compares them together. To be able 
 to comprehend, in one view, a combination 
 of steps of this kind, is more difficult, and 
 seems to require a superior natural ability. 
 In all, it may be much improved by habit. 
 
 But the highest talent in reasoning is the 
 invention of proofs; by which, truths re- 
 mote from the premises are brought to light. 
 In all works of understanding, invention 
 has the highest praise : it requires an ex- 
 tensive view of what relates to the subject, 
 and a quickness in discerning those affinities 
 and relations which may be subservient to 
 the purpose. 
 
 In all invention there must be some end 
 in view : and sagacity in finding out the 
 road that leads to this end, is, I think, what 
 we call invention. In this chiefly, as I ap- 
 prehend, and in clear and distinct concep- 
 tions, consists that superiority of under- 
 standing which we call genivs. [675] 
 
 In every chain of reasoning, the evidence 
 of the last conclusion can be no greater than 
 that of the weakest link of the chain, what- 
 ever may be the strength of the rest. 
 
 The most remarkable distinction of rea- 
 sonings is, that some are probable, others 
 demonstrative. 
 
 In every step of demonstrative reason- 
 ing, the inference is necessary, and we per- 
 ceive it to be impossible that the conclusion 
 should not follow from the premises. In 
 probable reasoning, the connection between 
 the premises and the conclusion is not neces- 
 sary, nor do we perceive it to be impossible 
 that the first should be true while the last 
 is false. 
 
 Hence, demonstrative reasoning has no 
 degrees, nor can one demonstration be 
 stronger than another, though, in relation 
 to our faculties, one may be more easi'v 
 comprehended than another. Every do. 
 
 [673-675]
 
 CHAP. I.] OF REASONING, AND OF DEMONSTRATION. 
 
 477 
 
 monstration gives equal strength to the con- 
 clusion, and leaves no possibility of its being 
 false. 
 
 It was, I think, the opinion of all the 
 ancients, that demonstrative reasoning can 
 be applied only to truths that are necessary, 
 and not to those that are contingent. In 
 this, I believe, they judged right. Of all 
 created things, the existence, the attributes, 
 and, consequently, the relations resulting 
 from those attributes, are contingent. They 
 depend upon the will and power of Him who 
 made them. These are matters of fact, and 
 admit not of demonstration. 
 
 The field of demonstrative reasoning, 
 therefore, is the various relations of things 
 abstract, that is, of things which we con- 
 ceive, without regard to their existence. 
 Of these, as they are conceived by the mind, 
 and are nothing but what they are conceived 
 to be, we may have a clear and adequate 
 comprehension. Their relations and attri- 
 butes are necessary and immutable. They 
 are the things to which the Pythagoreans 
 and Platonists gave the name of ideas. I 
 would beg leave to borrow this meaning of 
 the word idfia from those ancient philoso- 
 phers, and theu I must agree with them, 
 that ideas are the only objects about which 
 we can reason demonstratively. [67G] 
 
 There are many even of our ideas about 
 which we can carry on no considerable train 
 of reasoning. Though they be ever so well 
 defined and perfectly comprehended, yet 
 their agreements and disagreements are few, 
 and these are discerned at once. We may 
 go a step or two in forming a conclusion 
 with regard to such objects, but can go no 
 farther. There are others, about which wo 
 may, by a long train of demonstrative rea- 
 soning, arrive at conclusions very remote 
 and unexpected. 
 
 The reasonings I have met with that can 
 be called strictly demonstrative, may, I 
 think, be reduced to two classes. They are 
 either metaphysical, or they are mathe- 
 matical. 
 
 In metaphysical reasoning, the process is 
 always short. Tlie conclusion is but a step 
 or two, seldom more, from the first principle 
 or axiom on which it is grounded, and the 
 different conclusions depend not one upon 
 another. 
 
 It is otherwise in mathematical reason- 
 ing. Here the field has no limits. One 
 proposition leads on to another, that to a 
 third, and so on without end. 
 
 It' it should be asked, why demonstrative 
 reasoning has so wide a field in mathema- 
 tics, while, in other abstract sulijects, it is 
 confined within very narrow limits, I con- 
 ceive this is chiefly owing to the nature of 
 quantity, tlie object of matliomatics. 
 
 Every quantity, as it has magnitude, and 
 is divisible into parts without end, so, in 
 [G7G-«7H] 
 
 respect of its magnitude, it has a certain 
 ratio to every quantity of the kind. The 
 ratios of quantities are innumerable, such 
 as, a half, a third, a tenth, double, triple. 
 [677] AH the powers of number are in- 
 sufficient to express the variety of ratios. 
 For there are innumerable ratios wliich 
 cannot be perfectly expressed by numbers, 
 such as, the ratio of the side to the diagonal 
 of a square, or oi'the circumference of acircle 
 to the diameter. Of this infinite variety of 
 ratios, every one may be clearly conceived 
 and distinctly expressed, so as to be in no 
 danger of being mistaken for any other. 
 
 Extended quantities, such as lines, sur- 
 faces, solids, besides the variety of relations 
 they have in respect of magnitude, have no 
 less variety in respect of figure ; and every 
 mathematical figure may be accurately 
 defined, so as to distinguish it from all 
 others. 
 
 There is nothing of this kind in other 
 objects of abstract reasoning. Some of 
 them have various degrees ; but these are 
 not capable of measure, nor can be said to 
 have an assignable ratio to others of the 
 kind. They are either simple, or com- 
 pounded of a few indivisible parts ; and 
 therefore, if we may be allowed the expres- 
 sion, can touch only in few points. But 
 mathematical quantities being made up of 
 parts without number, can touch in inim- 
 merable points, and be compared in innu- 
 merable different ways. 
 
 There have been attempts made to mea- 
 sure the merit of actions by the ratios of 
 the affections and principles of action from 
 which they proceed. I'liis may perhaps, 
 in the way of analogy, serve to illustrate 
 what was before known ; but I do not think 
 any truth can be discovered in this way. 
 There are, no doubt, degrees of benevolence, 
 self-love, and other affections ; but, wlien 
 we apply ratios to them, I apprehend we 
 have no distinct meaning. 
 
 Some demonstrations are called direct, 
 others indirect. The first kind leads directly 
 to the conclusion to be proved. Of the 
 indirect, some are called demonstrations ad 
 alisurdnm. In tliesc, the proposition con- 
 tradictory to that which is to be proved ia 
 demonstrated to be false, or to lead to an 
 absurdity ; whence it follows, that its con- 
 tradictory — that is, the proposition to be 
 proved — is true. This inference is grounded 
 upon an axiom in logic, that of two contra- 
 dictory propositions, if one be false, the 
 other nmst be trui'.* [<i7U] 
 
 Another kind of indirect demonstration 
 proceeds by enumerating all tht> supposi- 
 tions that can possibly be made eoru-crning 
 the proposition to be proved, ami tlun 
 
 ■* This 18 called xhe principle t\f Excln<Ud Middle— 
 \\z., btlwcen two contrailictorics.— 11
 
 478 
 
 ON THE INTELLECTUAL POWERS. 
 
 Lessait vir. 
 
 demonstrating that all of them, excepting 
 that which is to be proved, are false ; whence 
 it follows, that the excepted supposition is 
 true. Thus, one line is proved to be equal 
 to another, by proving first that it cannot be 
 greater, and then that it cannot be less : for 
 it must be either greater, or less, or equal ; 
 and two of these suppositions being demon- 
 strated to be false, the third must be true. 
 
 All these kinds of demonstration are used 
 in mathematics, and perhaps some others. 
 They have all equal strength. The direct 
 demonstration is preferred where it can be 
 had, for this reason only, as I a])prehend, 
 because it is the shortest road to the con- 
 clusion. The nature of the evidence, and 
 its strength, is the same in all : only we 
 are conducted to it by different roads. 
 
 CHAPTER II. 
 
 WHETHER MORALITY BE CAPABLE OF 
 DEMONSTRATION. 
 
 What has been said of demonstrative 
 reasoning, may help us to judge of an opi- 
 nion of Mr Locke, advanced in several places 
 of his Essay — to wit, " That morality is 
 capable of demonstration as well as mathe- 
 matics." 
 
 In book III., chap. 11, having observed 
 that mixed modes, especially thttee belong- 
 ing to morality, being such combiriations of 
 ideas as the mind puts together of its own 
 choice, the signification of their names 
 may be perfectly and exactly defined, he 
 adds— [679] 
 
 Sect. IC. "■ Upon this ground it is that I 
 am bold to think that morality is capable of 
 demonstration as well as mathematics ; since 
 the precise real essence of the things moral 
 words stand for may be perfectly known, 
 and so the congruity or incongruity of the 
 things themselves be certainly discovered, 
 in which consists perfect knowledge. Nor 
 let any one object. That the names of sub- 
 stances are often to be made use of in mo- 
 rality, as well as those of modes, from 
 which will arise obscurity ; for, as to sub- 
 stances, wlien concerned in moral dis- 
 courses, their divers natures are not so 
 much inquired into as supposed : v. g. When 
 we say that man is subject to law, we mean 
 nothing by man but a corporeal rational 
 creature : what the real essence or other 
 qualities of that creature are, in this case, 
 is no way considered." 
 
 Again, in book IV., ch. iii., § 18:—" The 
 idea of a Supreme Being, whose workman- 
 ship we are, and the idea of ourselves, being 
 such as are clear in us, would, I suppose, 
 if duly considered and pursued, afford such 
 foundation of our duty and rules of action 
 aa might place morality among the sciences 
 
 capable of demonstration. The relation of 
 other modes may certainly be perceived, as 
 well as those of number and extension ; and 
 I cannot see why they should not be cap- 
 able of demonstration, if due methods were 
 thought on to examine or pursue their 
 agreement or disagreement." 
 
 lie afterwards gives, as instances, two 
 ])ropositions, as moral propositions of which 
 we may be as certain as of any in mathe- 
 matics ; and considers at large what may 
 have given the advantage to the ideas of 
 quantity, and made them be thought more 
 capable of certainty and demonstration. [ 680 ] 
 Again, in the 12th chapter of the same 
 book, § 7, 8 :— " This, I think, I may say, 
 that, if other ideas that are the real as ^y&\ 
 as nominal essences of their several species 
 were pursued in the way familiar to mathe- 
 maticians, they would carry our thoughts 
 farther, and with greater evidence and 
 clearness, than possibly we are apt to ima- 
 gine. This gave me the confidence to 
 advance that conjecture which I suggest, 
 chap iii. — viz., That morality is capable of 
 demonstration as well as mathematics." 
 
 From these passages, it appears that this 
 opinion was not a transient thought, but 
 what he had revolved in his mind on dif- 
 ferent occasions. He offers his reasons for 
 it, illustrates it by examples, and considers 
 at length the causes that have led men to 
 think mathematics more capable of demon- 
 stration than the principles of morals. 
 
 Some of his learned correspondents, par- 
 ticularly his friend Mr Molyneux, urged 
 and importuned him to compose a system 
 of morals according to the idea he had ad- 
 vanced in his Essay ; and, in his answer to 
 these solicitations, he only pleads other oc- 
 cupations, without suggesting any change of 
 his opinion, or any great difficulty in the 
 execution of what was desired. 
 
 The reason he gives for this opinion is 
 ingenious ; and his regard for virtue, the 
 highest prerogative of the human species, 
 made him fond of an opinion which seemed 
 to be favourable to virtue, and to have a 
 just foundation in reason. 
 
 We need not, however, be afraid that the 
 interest of virtue may suffer by a free and 
 candid examination of this question, or in- 
 deed of any question whatever. For the 
 interests of truth and of virtue can never 
 be found in opposition. Darkness and error 
 may befriend vice, but can never be favour- 
 able to virtue. [681] 
 
 Those philosophers who think that our 
 determinations in morals are not real judg- 
 ments — that right and wrong in human con- 
 duct are only certain feelings or sensations 
 in the person who contemplates the action 
 — must reject Mr Locke's opinion without 
 exammation. For, if the principles of mo- 
 rals be not a matter of judgment, but of 
 
 [679-6811
 
 CHAP. II.] AV^HETHER iMORALI'i Y BE DEMONSTRABLE. 
 
 479 
 
 feeling only, there can be no demonstration 
 of them ; nor can any other reason be given 
 for them, but that men are so constituted 
 by the Author of their being as to contem- 
 plate with pleasure the actions we call vir- 
 tuous, and with disgust those we call vicious. 
 
 It is not, therefore, to be expected that 
 the philosophers of this class should think 
 this opinion of Mr Locke worthy of ex- 
 amination, since it is founded upon what 
 they think a false hypothesis. But if our 
 determinations in morality be real judg- 
 ments, and, like all other judgments, be 
 either true or false, it is not unimportant 
 to understand ujxm what kind of evidence 
 those judgments rest. 
 
 The argument offered by Mr Locke, 
 to shew that morality is capable of demon- 
 stration, is, " That the precise real essence 
 of the things moral words stand for, may be 
 perfectly known, and so the congruity or 
 incongruity of the things themselves be 
 perfectly discovered, in which consists per- 
 fect knowledge." 
 
 It is true, that the field of demonstration 
 IS the various relations of things conceived 
 abstractly, of which we may have perfect 
 and adequate conceptions. And Mr Locke, 
 taking all the things which moral words 
 stand for to be of this kind, concluded that 
 morality is as capable of demonstration as 
 mathematics. 
 
 I acknowledge that the names of the 
 virtues and vices, of right and obligation, 
 of liberty and property, stand for things 
 abstract, which may be accurately defined, 
 or, at least, conceived as distinctly and 
 adeqnatelyas mathematical quantities. And 
 thence, indeed, it follows, that their mutual 
 relations may be perceived as clearly and 
 certainly as mathematical truths. [682] 
 
 Of this Mr Locke gives two pertinent 
 examples. The first — " Where there is no 
 property, there is no injustice, is," says he, 
 " a proposition as certain as any demon- 
 stration in Euclid." 
 
 When injustice is defined to be a viola- 
 tion of property, it is as necessary a truth, 
 that there can be no injustice where there 
 is no property, as that you cannot take 
 from a man that which he has not. 
 
 The second example is, " That no 
 government allows absolute liberty." This 
 is a truth no less certain and necessary. 
 
 Such abstract ti-uths I would call meta- 
 physical ratiier than moral. We give the 
 name of mathematical to truths that ex- 
 press the relations of quantities considered 
 abstractly ; all other abstract truths may 
 be called metaphysical. I'ut ii' those men- 
 tioned by Mr Locke are to be called moral 
 trutliB, I agree with him that there arc 
 many such that are necessarily true, and 
 that have all tiie evidence that mathemati- 
 cal trutlis can have. 
 rGH2, GH.^] 
 
 It ought, however, to be remembered, 
 that, as was before observed, the relations 
 of things abstract, perceivable by as, ex- 
 cepting those of mathematical quantities, 
 are few, and, for the most part, immediately 
 discerned, so as not to require that train 
 of reasoning which we call demonstration. 
 Their evidence resembles more that of 
 mathematical axioms than mathematical 
 propositions. 
 
 This appears in the two propositions 
 given as examples by Mr Locke. The first 
 follows immediately from the definition of 
 injustice ; the second from the definition of 
 government. Their evidence may more 
 properly be called intuitive than demon- 
 strative. And this I apprehend to be the 
 case, or nearly tlie case, of all abstract 
 truths that are not mathematical, for the 
 reason given in the last chapter. [683] 
 
 The propositions which I think are pro- 
 perly called moral, are those that affirm 
 some moral obligation to be, or not to be 
 incumbent on one or more individual per- 
 sons. To such propositions, Mr Locke's 
 reasoning does not apply, because the sub- 
 jects of the proposition are not things whose 
 real essence may be perfectly known. They 
 are the creatures of God ; their obligation 
 results from the constitution which God 
 hath given them, and the circumstances 
 in which he hath placed them. That an 
 individual hath such a constitution, and is 
 placed in such circumstances, is not an 
 abstract and necessary, but a contingent 
 truth. It is a matter of fact, and, there- 
 fore, not capable of demonstrative evidence, 
 which belongs only to necessary truths. 
 
 The evidence which every man hatli of 
 his own existence, though it be irresistible, 
 is not demonstrative. And the same thing 
 may be said of the evidence which every 
 man hath, that he is a moral agent, and 
 under certain moral obligations. In like 
 manner, the evidence we have of the exist- 
 ence of other men, is not demonstrative ; 
 nor is the evidence we have of their being 
 endowed with those faculties which make 
 them moral and accountable agents. 
 
 If man had not the faculty given him by 
 God of perceiving certain things in conduct 
 to be right, and others to l)e wrong, and of 
 perceiving his obligation to do what is light, 
 and not to do what is wrong, he would not 
 be a moral and accountable being. 
 
 ]f man be endowed with such a faculty, 
 there nmst be some things which, by this 
 faculty, are inunediately discerned to be 
 right,"and others to be wrong ; and, there- 
 fore, there must be in morals, as in other 
 sciences, first i)rinci])le.s which do not do- 
 rive their evidence from any antecedent 
 principles, but may be said to be mtuitively 
 discerned. 
 
 Moral truths, there ""ore, may be divided
 
 480 
 
 ON THE INTELLECTUAL POWERS. 
 
 [[essay Vll. 
 
 into two classes — to wit, such as are self- 
 evident to every man whose understanding 
 and moral faculty are ripe, and such as are 
 deduced by reasoning from those that are 
 self-evident. If the first be not discerned 
 without reasoning, the last never can be so 
 by any reasoning. [G84] 
 
 If any man could say, with sincerity, that 
 he is conscious of no obligation to consult 
 his own present and future happiness ; to 
 be faithful to his engagements ; to obey his 
 Maker ; to injure no man ; I know not 
 what reasoning, either probable or demon- 
 strative, I could use to convince him of ariy 
 moral duty. As you cannot reason in 
 mathematics with a man who denies the 
 axioms, as little can you reason with a man 
 in morals who denies tlie first principles of 
 morals. The man who does not, by the light 
 of his own mind, perceive some things in 
 conduct to be right, and others to be wrong, 
 is as incapable of reasoning about morals 
 as a blind man is about colours. Such a 
 man, if any such man ever was, would be 
 no moral agent, nor capable of any moral 
 obligation. 
 
 Some first principles of morals must be 
 immediately discerned, otherwise we have 
 no foundation on which others can rest, or 
 from which we can reason. 
 
 Every man knows certainly, that, what he 
 approves in other men, he ought to do in 
 like circumstances, and that he ought not to 
 do what he condemns in other men. Every 
 man knows that he ought, with candour, to 
 use the best means of knowing his duty. 
 To every man who has a conscience, these 
 things are self-evident. They are imme- 
 diate dictates of our moral faculty, which is 
 a part of the human constitution ; and every 
 man condemns himself, whether he will or 
 not, when he knowingly acts contrary to 
 them. The evidence of these fundamental 
 principles of morals, and of others that 
 might be named, appears, therefore, to me 
 to be intuitive rather than demonstrative. 
 
 The man who acts according to the dic- 
 tates of his conscience, and takes due pains 
 to be rightly informed of his duty, is a per- 
 fect man with regard to morals, and merits 
 no blame, whatever may be the imperfec- 
 tions or errors of his understanding. He 
 who knowingly acts contrary to them, is 
 conscious of guilt, and self-condemned. 
 Every particular action that falls evidently 
 within the fundamental rules of morals, is 
 evidently his duty ; and it requires no rea- 
 soning to convince him that it is so. [G85] 
 
 Thus, I think it appears, that every man 
 of common understanding knows certainly, 
 and without reasoning, the ultimate ends 
 he ought to pursue, and that reasoning is 
 necessary only to discover the most proper 
 means of attaining them ; and in this, in- 
 deed, a good man may often be in doubt. 
 
 Thus, a magistrate knows that it is liis 
 duty to promote the good of the community 
 which hath intrusted him with authority ; 
 and to offer to prove this to him by reason- 
 ing, would be to affront him. But whether 
 such a scheme of conduct in his office, or 
 another, may best serve that end, he may 
 in many cases be doubtful. I believe, in 
 such cases, he can very rarely have demon- 
 strative evidence. His conscience deter- 
 mines the end he ouglit to pursue, and he 
 has intuitive evidence that his end is good ; 
 but prudence nmst determine the means 
 of attaining that end ; and prudence can 
 very rarely use demonstrative reasoning, 
 but must rest in what appears most proba- 
 ble. 
 
 I apprehend, that, in every kind of duty 
 we owe to God or man, the case is similar — 
 that is, that the obligation of the most 
 general rules of duty is self-evident ; that 
 the application of those rules to particular 
 actions is often no less evident ; and that, 
 when it is not evident, but requires reason- 
 ing, that reasoning can very rarely be of 
 the demonstrative, but must be of the pro- 
 bable kind. Sometimes it depends upon 
 the temper, and talents, and circumstances 
 of the man himself; sometimes upon the 
 character and circumstances of others ; 
 sometimes upon both ; and these are things 
 which admit not of demonstration. [686) 
 
 Every man is bound to employ the talents 
 which God hath given him to the best pur- 
 pose ; but if, through accidents which he 
 could not foresee, or ignorance which was 
 invincible, they be less usefully employed 
 than they might have been, this will not be 
 imputed to him by his righteous Judge. 
 
 It is a common and a just observation, 
 that the man of virtue plays a surer game 
 in order to obtain his end than the man of 
 the world. It is not, however, because he 
 reasons better concerning the means of 
 attaining his end ; for the children of this 
 world are often wiser in their generation 
 than the children of light. But the reason 
 of the observation is, that involuntary 
 errors, unforeseen accidents, and invincible 
 ignorance, which affect deeply all the con- 
 cerns of the present world, have no effect 
 upon virtue or its reward. 
 
 In the common occurrences of life, a man 
 of integrity, who hath exercised his moral 
 faculty in judging what is right and what 
 is wrong, sees his duty without reasoning, 
 as he sees the highway. The cases that 
 require reasoning are few, compared with 
 those that require none ; and a man may 
 be very honest and vu-tuous who cannot 
 reason, and who knows not what demon- 
 stration means. 
 
 The power of reasoning, in those that 
 have it, may be abused in morals, as in 
 other matters. To a man who uses it with 
 
 [[684-686]
 
 (HAP. Ill 
 
 •] 
 
 OF PROBABLE REASONING. 
 
 481 
 
 an upright heart, and a single eye to find 
 what is his dutv, it will be of great use ; 
 but when it is used to justify what a man 
 has a strong inclination to do, it will only 
 serve to deceive himself and others. When 
 a man can reason, his passions will reason, 
 and they are the most cunning sophists we 
 meet with. 
 
 If the rules of virtue were left to be dis- 
 covered by demonstrative reasoning, or by 
 reasoning of any kind, sad would be the 
 condition of the far greater part of men, 
 who have not the means of cultivating the 
 power of reasonuig. As virtue is the busi- 
 ness of all men, the first principles of it are 
 written in their hearts, in cliaracters so 
 legible that no man can pretend ignorance 
 of them, or of his obligation to practise 
 them. [6S7] 
 
 Some knowledge of duty and of moral 
 obligation is necessary to all men. With- 
 out it they could not be moral and account- 
 able creatures, nor capable of being mem- 
 bers of civil society. It may, therefore, 
 be presumed that Nature has put this 
 knowledge within the reach of all men. 
 Reasoning and demonstration are weapons 
 which the greatest part of mankind never 
 was able to wield. The knowledge that is 
 necessary to all, must be attainable by all. 
 We see it is so in what pertains to the 
 natural life of man. 
 
 Some knowledge of things that are useful 
 and things that are hurtful, is so necessary 
 to all men, that without it the species would 
 soon perish. But it is not by reasoning 
 that this knowledge is got, far less by de- 
 monstrative reasoning. It is by our senses, 
 by memory, by experience, by information ; 
 means of knowledge that are open to all 
 men, and put the learned and the unlearned, 
 those who can reason and those who can- 
 not, upon a level. 
 
 It may, therefore, be expected, from the 
 analogy of nature, that such a knowledge 
 of morals as is necessary to all men should 
 be had by means more suited to the abili- 
 ties of all men than demonstrative reastJii- 
 ing is. 
 
 This, I apprehend, is in fact the case. 
 When men's faculties are ripe, the first 
 principles of morals, into which all moral 
 reaso::ing may be resolved, are perceived 
 intuitively, and in a manner more analogous 
 to the perceptions of sense than to the con- 
 clusions of demonstrative reasoning. [(i88] 
 Ujion the whole, I agree with ]Mr Locke, 
 that propositions expressing the congruities 
 and incongruities of things abstract, which 
 moral words stand for, may have all the 
 evidence of mathematical truths. I'ut this 
 is not peculiar to tilings which moral words 
 stand for. It is coninion to abstract pro- 
 positions of every kind. For instance, you 
 cannot take from a man what he has not. 
 [687-689] 
 
 A man cannot be bound and perfectly free 
 at the same time. I think no man will 
 call these moral iruths; but they are neces- 
 sary truths, and as evident as any in mathe- 
 matics. Indeed, they are very nearly allied 
 to the two which Mr Locke gives as in- 
 stances of moral propositions capable of 
 demonstration. Of such abstract proposi- 
 tions, I think it may more properly be said 
 that they have the evidence of mathemati- 
 cal axioms, than that they are capable of 
 demonstration. 
 
 There are propositions of another kind, 
 which alone deserve the name of moral pro- 
 positions. They are such as affirm some- 
 thing to be the duty of persons that really 
 exist. These are not abstract propositions; 
 and, therefore, BIr Locke's reasoning does 
 not apply to them. The truth of all such 
 propositions depends upon the constitution 
 and circumstances of the persons to whom 
 they are applied. 
 
 Of such propositions, there are some that 
 are self-evident to every man that has a 
 conscience 4 and these arc tlie principles 
 from which all moral reasoning must be 
 drawn. They may be called the axioms of 
 morals. But our reasoning from these 
 axioms to any duty that is not self-evident 
 can very rarely be demonstrative. Nor is this 
 any detriment to the cause of virtue, because 
 to act against what appears most probable 
 in a matter of duty, is as real a trespass 
 against the first principles (f morality, as 
 to act against demonstration ; and, because 
 he who has but one talent in reasoning, and 
 makes the proper use of it, shall be ac- 
 cepted, as well as he to wlioin God has 
 given ten. [689] 
 
 CHAPTER III. 
 
 OF I'ROBABLE REASONING. 
 
 The field of demonstration, as has been 
 observed, is necessary truth : the field of 
 probable reasoning is contiiigout truth — not 
 what necessarily mnst be at all times, but 
 what is, or was, or shall be. 
 
 No contingent truth is capable of strict 
 demonstration ; but necessary truths mr.y 
 sometimes have probable evidence. 
 
 Dr Wallis discovered many important 
 mathematical truths, by that kind of induc- 
 tion wiiicli draws a general conclusion from 
 particular [iremises. This is not strict de- 
 monstration, l>ut, in some cases, gives as 
 full conviction as demonstration itself: and 
 a man may be certain, that a truth is de- 
 monstrable before it ever has been demon- 
 strated. In other cases, a inatbenmtical 
 pr(i|)ositiiiii may have suidi pmliable evi- 
 deuce from induction or analogy as en- 
 courages the mathematician to investigata 
 
 31
 
 482 
 
 ON THE INTELLECTUAL POWERS. 
 
 [essay VII. 
 
 its demonstration. But still the reasoning, 
 proper to mathematical and other necessary 
 truths, is demonstration ; and that which is 
 proper to contingent truths, is probable 
 reasoning. 
 
 These two kinds of reasoning differ in 
 other respects. In demonstrative reason- 
 ing, one argument is as good as a thousand- 
 On« demonstration may be more elegant 
 tlian another ; it may be more easily com- 
 prehended, or it may be more subservient 
 to some purpose beyond the present. On 
 any of these accounts it may deserve a 
 preference : but then it is sufficient by it- 
 self ; it needs no aid from another ; it can 
 receive none. To add more demonstrations 
 of the same conclusion, would be a kind of 
 tautology in reasoning ; because one de- 
 monstration, clearly comprehended, gives 
 all the evidence we are capable of receiv- 
 ing. [690] 
 
 The strength of probable reasoning, for 
 the most part, depends not upon any one 
 argument, but upon many, which unite 
 their force, and lead to the same conclusion. 
 Any one of them by itself would be insuf- 
 ficient to convince ; but the whole taken 
 together may have a force that is irresistible, 
 so that to desire more evidence would be 
 absurd. Would any man seek new argu- 
 ments to prove that there were such persons 
 as King Charles I. or Oliver Cromwell ? 
 
 Such evidence may be compared to a rope 
 made up of many slender filaments twisted 
 together. The rope has strength more 
 than sufficient to bear the stress laid upon 
 it, though no one of the filaments of which 
 it is composed would be sufficient for that 
 purpose. 
 
 It is a common observation, that it is 
 unreasonable to require demonstration for 
 things which do not admit of it. It is no 
 less unreasonable to require reasoning of 
 any kind for things which are known with- 
 out reasonine;. All reasoning must be 
 grounded upon truths which are known 
 without reasoning. In every branch of real 
 knowledge there must be first principles 
 whose truth is known intuitively, without 
 reasoning, either probable or demonstrative. 
 They are not grounded on reasoning, but 
 all reasoning is grounded on them. It has 
 been shewn, that there are first principles 
 of necessary truths, and first principles of 
 contingent truths. Demonstrative reason- 
 ing is grounded upon the former, and pro- 
 bable reasoning upon the latter. 
 
 That we may not be embarrassed by the 
 ambiguity of words, it is proper to observe, 
 that there is a popular meaning of probable 
 evidence, which ought not to be confounded 
 with the philosophical meaning, above ex- 
 plained. [091] 
 
 In common language, probable evidence 
 is considered as an inferior degree of evi- 
 
 dence, and is opposed to certainty : so that 
 what is certain is more than probable, and 
 what is only probable is not certain. Phi- 
 losophers consider probable evidence, not 
 as a degree, but as a species of evidence, 
 which is opposed, not to certainty, but to 
 another species of evidence, called demon- 
 stration. 
 
 Demonstrative evidence has no degrees ; 
 but probable evidence, taken in the philo- 
 sophical sense, has all degrees, from the 
 very least to the greatest, which we call 
 certainty. 
 
 That there is such a city as Rome, I am 
 as certain as cf any proposition in Euclid ; 
 but the evidence is not demonstrative, but 
 of that kind which philosophers call pro- 
 bable. Yet, in common language, it would 
 sound oddly to say, it is probable there is 
 such a city as Rome, because it would 
 imply some degree of doubt or uncertainty. 
 
 Taking probable evidence, therefore, in 
 the philosophical sense, as it is opposed to 
 demonstrative, it may have any degrees of 
 evidence, from the least to the greatest. 
 
 I think, in most cases, we measure the 
 degrees of evidence by the effect they have 
 upon a sound understanding, when com- 
 prehended clearly and without prejudice. 
 Every degree of evidence perceived by the 
 mind, produces a proportioned degree of 
 assent or belief. The judgment may be in 
 perfect suspense between two contradictory 
 opinions, when there is no evidence for 
 either, or equal evidence for both. The 
 least preponderaney on one side inclines the 
 judgment in proportion. Belief is mixed 
 with doubt, more or less, until we come 
 to the highest degree of evidence, when 
 all doubt vanishes, and the belief is firm 
 and immovable. This degree of evidence, 
 the highest the human faculties can attain, 
 we call certainty. [692] 
 
 Probable evidence not only differs in kind 
 from demonstrative, but is itself of difi'erent 
 kinds. The chief of these I shall mention, 
 without pretending to make a complete 
 enumeration. 
 
 The first kind is that of human testimony, 
 upon which the greatest part of human 
 knowledge is built. 
 
 The faith of history depends upon it, as 
 well as the judgment of solemn tribunals, 
 with regard to men's acquired rights, and 
 with regard to their guilt or innocence, 
 when they are charged with crimes. A 
 great part of the business of the judge, of 
 counsel at the bar, of the historian, the 
 critic, and the antiquarian, is to canvass 
 and weigh this kind of evidence ; and no 
 man can act with common prudence in the 
 ordinary occurrences of life, who has not 
 some competent judgment of it. 
 
 The belief we give to testimony, in many 
 cases, is not solely grounded upon the vera- 
 
 [690-692]
 
 CHAP. III.] 
 
 OF PROBABLE REASONING. 
 
 483 
 
 city of the testifier. In a single testimony, 
 we consider the motives a man might have 
 to falsify. If there be no appearance of 
 any such motive, much more if there be 
 motives on the other side, his testimony has 
 weight independent of his moral character. 
 If the testimony be circumstantial, we con- 
 sider how far the circumstances agree to- 
 gether, and with things that are known. 
 It is so very difficult to fabricate a story 
 which cannot be detected by a judicious 
 examination of the circumstances, that it 
 acquires evidence by being able to bear 
 such a trial. There is an art in detecting 
 false evidence in judicial proceedings, well 
 known to able judges and barristers ; so 
 that I believe few false witnesses leave the 
 bar without suspicion of their guilt. 
 
 When there is an agreement of many 
 witnesses, in a great variety of circum- 
 stances, without the possibility of a previous 
 concert, the evidence may be equal to that 
 of demonstration. [693] 
 
 A second kind of probable evidence, is 
 the authority of those who are good judges 
 of the point in question. The supreme 
 court of judicature of the British nation, is 
 often determined by the opinion of lawyers 
 in a point of law, of physicians in a point of 
 medicine, and of other artists, in what re- 
 lates to their several professions. And, in 
 the common affairs of lite, we frequently 
 rely upon the judgment of others, in points 
 of which we are not proper judges our- 
 selves. 
 
 A third kind of probable evidence, is that 
 by which we recognise the identity of things 
 and persons of our acquaintance. That two 
 swords, two horses, or two persons, may be 
 so perfectly alike as not to be distinguish- 
 able by those to whom they are best known, 
 camiot be shewn to be impossible. But we 
 learn either from nature, or from experience, 
 that it never happens ; or so very rarely, 
 that a person or thing, well known to us, is 
 immediately recognised without any doubt, 
 when we perceive the marks or signs by 
 which we were in use to distinguish it from 
 all other individuals of the kind. 
 
 This evidence we rely upon in the most 
 important affairs of life ; and, by this evi- 
 dence, the identity, both of things and of 
 persons, is determined in courts of judica- 
 ture. 
 
 A fourth kind of probable evidence, is 
 that whicii we have of men's future actions 
 and conduct, from the general princi|)les of 
 action in man, or from our knowledge of the 
 individuals. 
 
 Notwitiistanding the folly and vice that 
 are to be found among men, there is a certain 
 degree of prudence an<l probity wliieli we 
 rely upon in every man that is not insane. 
 If it Were not so, no man would be safe in 
 the company of another, and tliere could be 
 
 no society among mankind. If men were 
 as much disposed to hurt as to do good, to 
 lie as to speak truth, they could not live to- 
 gether ; they would keep at as great dis- 
 tance from one another as possible, and the 
 race would soon perish, [b'94] 
 
 We expect that men will take some care 
 of themselves, of their family, friends, and 
 reputation ; that they will not injure othera 
 without some temptation ; that they will 
 have some gratitude for good offices, and 
 some resentment of injuries. 
 
 Such maxims with regard to human con- 
 duct, are the foundation of all political rea- 
 soning, and of common prudence in the con- 
 duct of life. Hardly can a man form any 
 project in public or in private life, which 
 does not depend upon the conduct of other 
 men, as well as his own, and which does not 
 go upon the supposition that men will act 
 such a part in such circumstances. This 
 evidence may be probable in a very high 
 degree ; but can never be demonstrative. 
 The best concerted project may fail, and 
 wise counsels may be frustrated, because 
 some individual acted a part which it would 
 have been against all reason to expect. 
 
 Another kind of probable evidence, the 
 counterpart of the last, is that by which we 
 collect men's characters and designs from 
 their actions, speech, and other external 
 signs. 
 
 We see not men's hearts, nor the prin- 
 ciples by which they are actuated ; but 
 there are external signs of their principles 
 and dispositions, which, though not certain, 
 may sometimes be more trusted than their 
 professions ; and it is from external signs 
 that we must draw all the knowledge we 
 can attain of men's characters. 
 
 The next kind of probable evidence I 
 mention, is that which mathematicians call 
 the probability of chances. 
 
 VV^e attribute some events to chance, be 
 cause we know only the remote cause which 
 must produce some one event of a num- 
 ber ; but know not the more immediate 
 cause which determines a particular event 
 of that number in preference to the others. 
 iGDo] 
 
 I think all the chances about which we rea- 
 son in mathematics are of this kind. Thus, 
 in throwing a just die upon a table, we say 
 it is an equal chance wiiich of the six sides 
 shall be turned up ; because neither the 
 jier.'^oii who throws, nor tiie bystanders, 
 know the ])rccise measure of force and di- 
 rection necessary to turn uj) any one side 
 ratlier than another. Tliere are here, there- 
 fore six events, one of which must happen ; 
 and as all are supposed to have equal pro- 
 bability, the jirolialjility of any one side 
 being tiiriicd up, tlic ace, I'lir iiLstance, ia as 
 one to tlie remaining mimlier, five. 
 
 The probability of turning up two aces 
 
 'Z 1 U
 
 484 
 
 ON THE INTELLECTUAL POWERS. 
 
 [eSSAV VII. 
 
 with two dice is as one to thirty-five ; because 
 here there are thirty-six events, each of 
 \f hich has equal probability. 
 
 Upon such principles as these, the doc- 
 trine of chances has furnished a field of de- 
 monstrative reasoning of great extent, al- 
 though the events about which this reason- 
 ing is employed be not necesssary, but con- 
 tingent, and be not certain, but probable. 
 
 This may seem to contradict a principle 
 before advanced, tliat contingent truths are 
 not capable of demonstration ; but it does 
 not : for, in the mathematical reasonings 
 about chance, the conclusion demonstrated, 
 is not, that such an event shall happen, but 
 that the probability of its happening bears 
 such a ratio to the probability of its failing ; 
 and this conclusion is necessary upon the 
 suppositions on which it is grounded. 
 
 The last kind of probable evidence I shall 
 meiition, is that by which the known laws 
 of Nature have been discovered, and the 
 effects which have been produced by them 
 in former ages, or which may be expected 
 in time to come. 
 
 The laws of Nature are the rules by which 
 the Supreme Being governs the world. We 
 deduce them only from facts that fall within 
 our own observation, or are properly attested 
 by those who have observed them. [696] 
 
 The knowledge of some of the laws of 
 nature is necessary to all men in the con- 
 duct of life. These are soon discovered 
 even by savages. They know that fire 
 burns, that water drowns, that bodies gra- 
 vitate towards the earth. They know that 
 day and night, summer and winter, regu- 
 larly succeed each other. As far back as 
 their experience and information reach, 
 they know that these have happened regu- 
 larly ; and, upon this ground, they are led, 
 by the. constitution of human nature, to ex- 
 pect that they will happen in time to come, 
 in like circumstances. 
 
 The knowledge which the philosopher 
 attains of the laws of Nature differs from 
 that of the vulgar, not in the first principles 
 on which it is grounded, but ill its extent 
 and accuracy. He collects with care the 
 phsenomena that lead to the same conclu- 
 sion, and compares them with those that 
 seem to contradict or to limit it. He ob- 
 serves the circumstances on which every 
 phsenomenon depends, and distinguishes 
 them carefully from those that are accident- 
 ally conjoined with it. He puts natural 
 bodies in various situations, and applies 
 them to one another in various ways, on 
 purpose to observe the effect ; and thus ac- 
 quires from his senses a more extensive 
 knowledge of the course of Nature in a short 
 time, than could be collected by casual ob- 
 servation in manv ages. 
 
 But what is the result of his laborious 
 researches ? It is, that, as far as he has 
 
 been able to observe, such things have 
 always happened in such circumstances, and 
 such bodies have always been found to have 
 such properties. These are matters of fact, 
 attested by sense, memory, and testunony, 
 just as the few facts which the vulgar know 
 are attested to them. 
 
 And what conclusions does the philoso. 
 pher draw from the facts he has collected ? 
 They are, that like events have haj-.pened 
 in former times in like circumstances, and 
 will happen in time to come ; and these con- 
 clusions are built on the very same ground 
 on which the shn]ile rustic concludes that 
 the sun will rise to-niorrow. [6J)7] 
 
 Facts reduced to general rules, and the 
 consequences of those general rules, are all 
 that we really know of the material world. 
 And the evidence that such general rules 
 have no exceptions, as well as the evidence 
 that they will be the same in time to come 
 as they have been in time past, can never 
 be demonstrative. It is only that species 
 of evidence which philosophers call probable. 
 General rules may have exceptions or limit- 
 ations which no man ever had occasion to 
 observe. The laws of nature may be changed 
 by him who established them. But we are 
 led by our constitution to rely upon their 
 continuance with as little doubt as if it was 
 demonstrable. 
 
 I pretend not to have made a complete 
 enumeration of all the kinds of probable 
 evidence ; but those I have mentioned are 
 sufficient to shew, that the far greatest part, 
 and the most interesting part of our know- 
 ledge, must rest upon evidence of this kind ; 
 and that many tlnngs are certain for which 
 we have only that kind of evidence which 
 philosophers call probable. 
 
 CHAPTER IV. 
 OF MR Hume's scepticism with regard to 
 
 REASON. 
 
 In the " Treatise of Human Nature," 
 book I. part iv. § 1, the author undertakes 
 to prove two points : — First, That all that 
 is called human knowledge (meaning de- 
 monstrative knowledge) is only probability ; 
 and, seconilii, That this probability, when 
 duly examined, evanishes by degrees, and 
 leaves at last no evidence at all : so that, 
 in the issue, there is no ground to believe 
 anyone proposition rather than its contrary ; 
 and " all those are certaiidy fools who reason 
 or believe anything." [698] 
 
 According to this account, reason, that 
 boasted prerogative of man, and the light of 
 his mind, is an ignu- fatuus, which misleads 
 the wandering traveller, and leaves him at 
 last in absolute darkness. 
 
 How 'unhappy is the condition of man, 
 
 [696-698]
 
 CHAP. IV.] OF Mil HUME'S SCEPriCiSM ABOUT REASON. 
 
 485 
 
 born under a uecessity of believing contra- 
 dictions, and of trusting to a guide who con- 
 fesses herself to be a false one ! 
 
 It is some comfort, that this doctrine can 
 never be seriously adopted by any man in 
 his senses. And after this author had 
 shewn that " all the rules of logic require a 
 total extinction of all belief and evidence," 
 he himself, and all men that are not insane, 
 nmst have believed many things, and yielded 
 assent to the evidence which he had ex- 
 tinguished. 
 
 This, indeei], he is so candid as to acknow- 
 ledge. " He finds himself absolutely and 
 necessarily determined, to live and talk and 
 act like other people in the common affairs 
 of life. And since reason is incapable of 
 dispelling these clouds, most fortunately it 
 happens, that nature herself suffices to that 
 purpose, and cures him of this philosophical 
 melancholy and delirium." See § 7- 
 
 This was surely a very kind and friendly 
 interposition of nature ; for the effects of 
 this philosophical delirium, if carried into 
 life, must have been very melancholy. 
 
 But what pity is it, that nature, (what- 
 ever is meant by that personage,) so kind 
 in curing this delirium, should be so cruel 
 as to cause it. Doth the same fountain 
 send forth sweet w-aters and bitter ? Is it 
 not more probable, that, if the cure was the 
 work of nature, the disease came from 
 another hand, and was the work of the 
 philosopher ? [6'99j 
 
 To pretend to prove by reasoning that 
 there is no force in reason, does indeed look 
 like a philosophical delirium. It is like a 
 man's pretending to see clearly, that he 
 himself and all other men are blind. 
 
 A common symptom of delirium is, to 
 think that all otlier men are fools or mad. 
 This appears to have been the case of our 
 author, who concluded, " That all those are 
 certainly fools who reason or believe any- 
 thing." 
 
 Whatever was the cause of this delirium, 
 it must be granted that, if it was real and 
 not feigned, it was not to be cured by rea- 
 soning ; for what can be more absurd than 
 to attempt to convince a man by reasoning 
 who disowns the authority of reason. It 
 was, therefore, very fortunate that Nature 
 found other means of curing it. 
 
 It may, however, not be improper to 
 inquire, whether, as the author thinks, it 
 ■Was produced by a just application of the 
 rules of logic, or, as others may be apt to 
 think, by the misapplication and abuse of 
 them. 
 
 First, Because we arc fallible, the autiior 
 infers that all knowledge degenerates into 
 jirobability. 
 
 'I'iiat man, and probalily every created 
 being, is fallible; and that a fallible being 
 cannot have that [icrfect compreiiension j 
 \liDi) 701 I 
 
 and assurance of truth which an infallible 
 being has — I think ought to be granted. It 
 becomes a fallible being to be modest, open 
 to new light, and sensible that, by some 
 false bias, or by rash judging, he may be 
 misled. If this be called a degree of scep- 
 ticism, I cannot help approving of it, being 
 persuaded that the man who makes the best 
 use he can of the faculties which God has 
 given him, without thinking them more per- 
 fect than they really are, may have all the 
 belief that is necessary in the conduct of 
 life, and all that is necessary to his accept- 
 ance with his Maker. [700] 
 
 It is granted, then, that human judg- 
 ments ought always to be formed with an 
 humble sense of our fallibility in judging. 
 
 This is all that can be inferred by the 
 rules of logic from our being fallible. And 
 if this be all that is meant by our know- 
 ledge degenerating into probability, I know 
 no person of a different opinion. 
 
 But it may be observed, that the author 
 here uses the word probability in a sense 
 for which I know no authority but his own. 
 Philosophers understand probability as op- 
 posed to demonstration ; the vulgar as 
 opposed to certainty ; but this author un- 
 derstands it as opposed to infallibility, which 
 no man claims. 
 
 One who believes himself to be fallible 
 may still hold it to be certain that two and 
 two make four, and that two contradictory 
 propositions cannot both be true. Ho may 
 believe some things to be probable only, 
 and other things to be demonstrable, with- 
 out making any pretence to infallibility. 
 
 If we use words in their proper meaning, 
 it is impossible that demonstration should 
 degenerate into probability from the imper- 
 fection of our faculties. Our judgment can- 
 not change the nature of the things about 
 which we judge. What is really demon- 
 stration, will still be so, whatever judgment 
 we form concerning it. It may, likewise, 
 be observed, that, when we mistake that foi 
 demonstration which really is not, the con- 
 sequence of this mistake is, not that de- 
 monstration degenerates into probability, 
 but that what we took to be demonstration 
 is no proof at all ; for one false step in .a 
 demonstration destroys the whole, but can- 
 not turn it into another kind of proof. 
 [701] 
 
 Upon the whole, then, this first conclu- 
 sion of our author, That the fallibility of 
 human judgment turns all knowledge into 
 probability, if understood literally, is absurd ; 
 but, if it be only a figure of speech, and 
 means no more but that, in all our judg- 
 ments, we ought to be sensible of our falli- 
 bility, and ought to hold our opinions with 
 that modesty that becomcM fallible crea- 
 tures—which 1 t:ik(' to be wiiat the ajlhor 
 meant — this, 1 think, nobody denicH, nor
 
 486 
 
 ON THE INTELLECTUAL POWERS. 
 
 [^ESSAY VII 
 
 was it necessary to enter into a laborious 
 proof of it. 
 
 One is never in greater danger of trans- 
 gressing against tiie rules of logic than in 
 attempting to prove what needs no proof. 
 Of this we have an inskinee in this very 
 case ; for the author begins his proof, that 
 all human judgments are fallible, with af- 
 firming that some are infallible. 
 
 " In all demonstrative sciences," says 
 he, " the rules are certain and infallible ; 
 but when we apply them, our fallible and 
 uncertain faculties are very apt to depart 
 from them, and fall into error." 
 
 He had forgot, surely, that the rules of 
 demonstrative sciences are discovered by 
 our fallible and uncertain faculties, and 
 have no authority but that of human judg- 
 ment. If they be infallible, some human 
 judgments are infallible; and there are many 
 in various branches of human knowledge 
 which have as good a claim to infallibility 
 as the rules of the demonstrative sciences. 
 
 We have reason here to find fault with 
 our author for not being sceptical enough, 
 as well as for a mistake in reasoning, when 
 he claims infallibility to certain decisions of 
 the human faculties, in order to prove that 
 all their decisions are fallible. 
 
 The second point which he attempts to 
 prove is. That this probabiUty, when duly 
 examined, suffers a continual diminution, 
 and at last a total extinction. 
 
 The obvious consequence of this is, that 
 no fallible being can have good reason to 
 believe anything at all ; but let us hear the 
 proof. [702] 
 
 " In every judgment, we ought to cor- 
 rect the first judgment derived from the 
 nature of the object, by another judgment 
 derived from the nature of the understand- 
 ing. Beside the original uncertainty inher- 
 ent in the subject, there arises another, 
 derived from the weakness of the faculty 
 which judges. Having adjusted these two 
 uncertainties together, we are obliged, by 
 our reason, to add a new uncertainty, de- 
 rived from the possibility of error in the 
 estimation we make of the truth and fidelity 
 of our faculties. This is a doubt of which, 
 if we would closely pursue our reasoning, 
 we cannot avoid giving a decision- But 
 this decision, though it should be favour- 
 able to our preceding judgment, being 
 founded only on probability, must weaken 
 still farther our first evidence. The third 
 uncertainty must, in like manner be criti- 
 cised by a fourth, and so on without end. 
 
 " Now, as every one of these uncertainties 
 takes away a part of the original evidence, 
 it must at last be reduced to nothing- Let 
 our first belief be ever so strong, it must in- 
 fallil ly perish, by passing through so many 
 examinations, each of which carries off 
 somewhat of its force and vigour. No finite 
 
 object can subsist under a decrease repeated 
 in infinitum. 
 
 " When I reflect on the natural fallibil- 
 ity of my judgment, I have less confidence 
 in my opinions than when I only consider 
 the objects concerning which I reason. And 
 when I proceed still farther, to turn the scru- 
 tiny against every ruccessive estimation I 
 make of ray faculties, all the rules of logic 
 require a continual diminution, and at last 
 a total extinction of belief and evidence." 
 
 This is the author's Achillean argument 
 against the evidence of reason, froTu which 
 he concludes, that a man who would govern 
 his belief by reason must believe nothing at 
 all, and that belief is an act, not of the co- 
 gitative, but of the sensitive part of our 
 nature. [703] 
 
 If there be any such thing as motion, 
 (said an ancient Sceptic,*) the swift-footed 
 Achilles could never overtake an old man 
 in a journey. For, suppose the old man to 
 set out a thousand paces before Achilles, 
 and that, while Achilles has travelled the 
 thousand paces, the old man has gone five 
 hundred ; when Achilles has gone the five 
 hundred, the old man has gone two hun- 
 dred and fifty ; and when Achilles has 
 gone the two hundred and fifty, the old 
 man is still one hundred and twenty-five 
 before him. Repeat these estimations in 
 infinitxim, and you will still find the old man 
 foremost ; therefore Achilles can never 
 overtake him ; therefore there can be no 
 such thing as motion. 
 
 The reasoning of the modern Sceptic 
 against reason is equally ingenious, and 
 equally convincing. ludeed, they have a 
 great similarity. 
 
 If we trace the journey of Achilles two 
 thousand paces, we shall find the very 
 point where the old man is overtaken. But 
 this short journey, by dividing it into an 
 infinite number of stages, with correspond- 
 ing estimations, is made to appear infinite. 
 In like manner, our author, subjecting 
 every judgment to an infinite number of 
 successive probable estimations, reduces 
 the evidence to nothing. 
 
 To return then to the argument of the 
 modern Sceptic. I examine the proof of a 
 theorem of Euclid. It appears to me to be 
 strict demonstration- But I may have 
 overlooked some fallacy ; therefore I ex- 
 amine it again and again, but can find no 
 flaw in it. I find all that have examined 
 it agree with me. I have now that evidence 
 of the truth of the proposition which I and 
 all men call demonstration, a;id that belief 
 of it which we call certainty. [704] 
 
 Here my sceptical friend interposes, and 
 assures me, that the rules of logic reduce 
 
 * Zeno Elcates. He is improperly called, nimpli- 
 citer, . Sceptic. — H. 
 
 [702-701]
 
 CHAP. IV.] OF MR HUME'S SCEPTICISM ABOUT REASON. 
 
 487 
 
 this demonstration to no evidence at all. 
 I am willing to hear what step in it he thinks 
 fallacious, and why. He makes no objec- 
 tion to any part of the demonstration, but 
 pleads my fallibility in judging. I have 
 made the proper allowance fortius already, 
 by being open to conviction. But, says he, 
 tliereare two uncertainties, the first inherent 
 in the subject, which I have already shewn 
 to have only probable evidence ; the second 
 arising from the weakness of the faculty 
 that judges. I answer, it is the weakness of 
 the faculty only that reduces this demonstra- 
 tion to what you call probability. You 
 must not therefore make it a second uncer- 
 tainty; for it is the same with the first. 
 To take credit twice in an account for 
 the same article is not agreeable to the 
 rules of logic. Hitherto, therefore, there 
 is but one uncertainty — to wit, my fallibility 
 in judging. 
 
 But, says my friend, you are obliged by 
 reason to add a new uncertainty, derived 
 from the possibility of error in the estima- 
 tion you make of the truth and fidelity of 
 your faculties. I answer — 
 
 This estimation is ambiguously ex- 
 pressed ; it may either mean an estimation 
 of my liableness to err by the misapplica- 
 tion and abuse of my faculties ; or it may 
 mean an estimation of my liableness to err 
 by conceiving my faculties to be true and 
 faithful, while they may be false and falla- 
 cious in themselves, even when applied in 
 the best manner. I shall consider this 
 estimation in each of these senses. 
 
 If the first be the estimation meant, it is 
 true that reason directs us, as fallible crea- 
 tures, to carry along with us, in all our 
 judgments, a sense of our fallibility. It is 
 true also, that we are in greater danger of 
 erring in some cases, and less in others ; 
 and that this danger of erring may, accord- 
 ing to the circumstances of the case, admit 
 of an estimation, which we ought likewise 
 to carry along with us in every judgment 
 we furin. [705] 
 
 A\'hen a demonstration is short and plain ; 
 when the point to be proved does not 
 touch our interest or our passions ; when 
 the faculty of judging, in such cases, has 
 acquired strength by much exercise — there is 
 less danger of erring ; when the contrary 
 circumstances take place, there is more. 
 
 In the present case, every circumstance 
 is favourable to the j udginent I have formed. 
 There cannot be less danger of erring in 
 any case, excepting, perhaps, when I judge 
 of a self-evident axiom 
 
 The Sceptic farther urges, that this deci- 
 sion, tliough favourable to my first jmlg- 
 mcnt, Ijoing founded only on prubaljility, 
 must still weaken the evidence of that judg- 
 ment- 
 Here I cannot help being of a quite con- 
 L70.5, 7061 
 
 trary opinion ; nor can I imagine how an 
 ingenious author could impose upon himself 
 so grossly ; for surely he did not intend to 
 impose upon his reader- 
 After repeated examination of a propo- 
 sition of Euclid, I judge it to be strictly 
 demonstrated ; this is my first judgment. 
 But, as I am liable to err from various 
 causes, I consider how far I may have been 
 misled by any of these causes in this judg- 
 ment. My decision ujwn this second point 
 is favourable to my first judgment, and 
 therefore, as I apprehend, nuist strengthen 
 it. To say that this decision, because it is 
 only probable, must weaken the first evi- 
 dence, seems to me contrary to all rules of 
 logic, and to common sense. 
 
 The first judgment may be compared to 
 the testimony of a credible witness ; the 
 second, after a scrutiny into the character 
 of the witness, wipes off' every objection 
 that can be made to it, and therefore surely 
 must confirm and not weaken his testi- 
 mony. [706] 
 
 But let us suppose, that, in another case, 
 I examine my first judgment upon some 
 point, and find that it was attended with 
 unfavourable circumstances, what, in rea- 
 son, and according to the rules of logic, 
 ought to be the effect of this discovery ? 
 
 The effect surely will be, and ought to 
 be, to make me less confident in my first 
 judgment, until I examine the point anew 
 in more favourable circumstances. If it 
 be a matter of importance, I return to 
 weigh the evidence of my first judgment. 
 If it was precipitate before, it must now be 
 deliberate in every point- If, at first, I 
 was in passion, I must now be cool. If I 
 liad an interest in the decision, I nmst 
 place the interest on the other side. 
 
 It is evident that this review of the sub- 
 ject may confirm my first judgment, not- 
 withstanding the suspicious circumstances 
 that attended it. Though the judge was 
 biassed or corrupted, it does not follow that 
 the sentence was unjust. The rectitude of 
 the decision does not depend upon the cha- 
 racter of the judge, but upon the nature of 
 the case. I-'rom that only, it must be deter- 
 mined whether the decision be just. The 
 circumstances that rendered it suspicious 
 are mere presumptions, which have no force 
 against direct evidence. 
 
 'I'hus, 1 have considered the effect of this 
 estinuition of our liableness to err in our 
 first judgnuMit, and have allowed to it all 
 the effect that reason an<l the rules of logic 
 permit. In the case I first supposed, and 
 in every case where we can discover no 
 cause of error, it affords a presumption in 
 favour of the first judgment. In other 
 cases, it may afford u j)resumption against 
 it. But the rules of logic rerjuire, that we 
 ehould not judge by presumptions, wliero
 
 488 
 
 ON THE INTELLECTUAL POWERS. 
 
 [essay VII, 
 
 we have direct evidence. The effect of an 
 unfavourable presumption should only be, 
 to make us examine the evidence with the 
 greater care. [707] 
 
 The sceptic urges, in tlie last place, that 
 this estimation must be subjected to another 
 estimation, that to another, and so on, iii in- 
 fiuilitm ; and as every new estimation takes 
 away from the evidence of the first judg- 
 ment, it must at last be totally annihilated. 
 
 I answer, first, It has been shewn above, 
 that the first estimation, supposing it un- 
 favourable, can only afford a presumption 
 against the first judgment; the second, 
 upon the same supposition, will be only the 
 presumption of a presumption ; and the 
 tl'ird, the presumption that there is a pre- 
 sumption of a presumption. This infinite 
 series of presumptions resembles an infinite 
 series of quantities, decreasing in gcome- 
 ti ical proportion, which amounts only to a 
 finite sum. The infinite series of stages of 
 Achilles'sjourney after the old man, amounts 
 only to two thousand paces ; nor can this 
 infinite series of presumptions outweigh one 
 solid argument in favour of the first judg- 
 ment, supposing them all to be unfavour- 
 able to it. 
 
 Secondly, I have shewn, that the estima- 
 tion of our first judgment may strengthen 
 it ; and the same thing may be said of all the 
 subsequent estimations. It would, there- 
 fore, be as reasonable to conclude, that the 
 first judgment will be brought to infallible 
 certainty when this series of estimations is 
 wholly in its favour, as that its evidence 
 will be brought to nothing by such a series 
 supposed to be wholly unfavourable to it. 
 But, in reality, one serious and cool re- 
 examination of the evidence by which our 
 first judgment is supported, has, and in 
 reason ought to have more force to strengthen 
 or weaken it, than an infinite series of such 
 estim.ations as our author requires. 
 
 Thiidli/, I know no reason nor rule in 
 logic, that requires that such a series of 
 estimations should i'ollow eyery particular 
 judgment. [708] 
 
 A wise man, who has practised reasoning, 
 knows that he is fallible, and carries this 
 conviction along with him in every judg- 
 ment he forms. He knows likewise that 
 he is more liable to err in some cases than 
 in others. He has a scale in his mind, by 
 which he estimates his liableness to err, and 
 by this he regulates the degree of his assent 
 in his first judgment upon any point. 
 
 The author's reasoning supposes, that a 
 man, when he forms his first judgment, 
 conceives himself to be infallible ; that by a 
 second and subsequent judgment, he dis- 
 covers that he is not infallible ; and that by 
 a third judgment, subsequent to the second, 
 he estimates his liableness to err in such a 
 case as the present. 
 
 If the man proceed in this order. I grant, 
 that his second judgment will, with good 
 reason, bring down the first from supposed 
 infallibility to fallibility ; and that his third 
 judgment will, in some degree, either 
 strengthen or weaken the first, as it is cor- 
 rected by the second. 
 
 But every man of understanding proceeds 
 in a contrary order. When about to judge 
 in any particular point, he knows already 
 that he is not infallible. He knows what 
 are the cases in which he is most or least 
 liable to err. The conviction of these things 
 is always present to his mind, and influences 
 the degree of his assent in his first judg- 
 ment, as far as to him a])pears reasonable. 
 
 If he should afterwards find reason to 
 suspect his first judgment, and desires to 
 have all tlie satiblaction his faculties can 
 give, reason v.ill direct him not to form 
 such a series of estimations upon estima- 
 tioiis, as this autb.or requires, but to examine 
 the evidence of his first judgment carefully 
 and coolly ; and this review niay very reason- 
 ably, according to its result, eitlierstrengthen 
 or weaken, or totally overturn his first 
 judgment. [709] 
 
 This infinite series of estimations, there- 
 fore, is not the method that reason directs, 
 in order to form our judgment in any case. 
 It is introduced without necessity, without 
 any use but to puzzle the understanding, 
 and to make us think, that to judge, even 
 in the simplest and plainest cases, is a mat- 
 ter of insurmountable difficulty and endless 
 labour ; just as the ancient Sceptic, to make 
 a journey of two thousand paces appear 
 endless, divided it into an infinite number 
 of stages. 
 
 But we observed, that the estimation 
 which our author requires, may admit of 
 another meaning, which, indeed, is more 
 agreeable to the expression, but inconsist- 
 ent with what he advanced before. 
 
 By the possibility of error in the estima- 
 tion of the truth and fidelity of our faculties, 
 may be meant, that we may err by esteem- 
 ing our faculties true and faithful, while they 
 may be false and fallacious, even when used 
 according to the rules of reason and logic. 
 
 If this be meant, I answer, /(»•.</, That 
 the truth and fidelity of our faculty of judg- 
 ing is, and must be taken for granted in 
 every judgment and in every estimation. 
 
 If the sceptic can seriously doubt of the 
 truth and fidelity of his faculty of judging 
 when properly used, and suspend his judg- 
 ment upon that point till he finds proof, his 
 scepticism admits of no cure by reasoning, 
 and he must even continue in it imtil he 
 have new faculties given him, which shall 
 have authority to sit in judgment upon the 
 old. Nor is there any need of an endless 
 succession of doubts upon this subject ; for 
 the first puts an end to all judgment and 
 
 £707-70.')"'
 
 cuAP. iv.J OF MR HUME'S SCEPTICISM ABOUT REASON. 
 
 489 
 
 reasoning, and to the possibility of convic- 
 tion by tliat means. The sceptic has here 
 got possession of a stronghold, which is im- 
 pregnable to reasoning, and we must leave 
 him in possession of it till Nature, by other 
 means, makes him give it up. [710] 
 
 Secondly, I observe, that this ground of 
 scepticism, from the supposed infidelity of 
 our faculties, contradicts what the author 
 before advanced in this very argument — to 
 wit, that " the rules of the demonstrative 
 sciences are certain and infallible, and that 
 truth is the natural effect of reason, and 
 that error arises from the irruption of other 
 causes." 
 
 But, perhaps, he made these concessions 
 unwarily. He is, therefore, at liberty to 
 retract them, and to rest his scepticism upon 
 this sole foundation, That no reasoning can 
 prove the truth and fidelity of our faculties. 
 Here lie stands upon firm ground ; for it is 
 evident that every argument offered to 
 prove the truth and fidelity of our faculties, 
 takes for granted the thing in question, and 
 is, therefore, that kind of sophism which 
 logicians call priitio prinripi'. 
 
 All we would ask of this kind of sceptic 
 IS, that he would be uniform and consistent, 
 and that his practice in life do not belie his 
 profession of scepticism, with regard to the 
 fidelity of his faculties ; for the want of faith, 
 as well as faith itself, is best shewn by 
 works. If a sceptic avoid the fire as much 
 as those who believe it dangerous to go 
 into it, we can hardly avoid thinking his 
 .scepticism to be feigned, and not real. 
 
 Our author, indeed, was aware, that 
 neither his scepticism nor that of any other 
 person, was able to endure this trial, and, 
 therefore, enters a caveat against it. 
 " 2s either I," says he, " nor any other per- 
 son was ever sincerely and constantly of 
 that opinion. Xature, by an absolute and 
 uncontrollable necessity, has determined us 
 to judge, as well as to breathe and feel. My 
 intention, therefure," says he, " in disphiy- 
 ing so carefully the arguments of that fan- 
 tastic sect, is only to njake the reader sen- 
 sible of the truth of my hypothesis, that all 
 our reasonings coneorningcausesand effects, 
 are derived from nothing but custom, and 
 that belief is more properly an act of the 
 [710-713] 
 
 sensitive than of the cogitative part of our 
 nature." [711] 
 
 We have before considered the first part 
 of this hypotliesis. Whether our reasoning 
 about causes be derived only from custom ? 
 
 The other part of the autiior's hypothesis 
 here mentioned is darkly expressed, though 
 the expression seems to be studied, as it is 
 put in Italics. It cannot, surely, mean 
 that belief is not an act of thinking. It is 
 not, therefore, the power of thinking that 
 he calls the cogitative part of our nature. 
 Neither can it be the power of judging, for 
 all belief implies judgment ; and to believe 
 a proposition means the same thing as to 
 judge it to be true. It seems, therefore, to 
 be the power of reasoning that lie calls the 
 cogitative part of our nature. 
 
 If this be the meaning, I. agree to it iu 
 part. The belief of fir.st principles is not 
 an act of the reasoning power ; for all rea- 
 soning must be grounded upon them. We 
 judge them to be true, and believe them 
 without reasoning. But why this power of 
 judging of first principles should be called 
 the sensitive part of our nature, I do not 
 imderstand. 
 
 As our belief of first principles is an act 
 of pure judgment without reasoning ; so 
 our belief of the conclusions drawn by rea- 
 soning from first principles, may, I think, be 
 called an act of the reasoning facult\'. 
 [712] 
 
 Upon the whole, I see only two conclu- 
 sions that can be fairly drawn from this 
 profound and intricate reasoning against 
 reason. The first is. That we are fallible 
 in all our judgments and in all our reason- 
 ings. The second. That the truth and 
 fidelity of our faculties can never be proved 
 by reasoning ; and, therefore, our belief of 
 it cannot be founded on reasoning. If the 
 last be what the author calls his hypothesis, 
 I subscribe to it, and think it not an hypo- 
 thesis, but a manifest truth; though 1 con- 
 ceive it to be very improperly expressed, by 
 saying that belief is more properly an act 
 of the sensitive than of tlie cogitative part 
 of our nature.* [711^] 
 
 * In the prcceiiiiig strictures, tlie .Sctp'jw '«a!;aiii 
 tfX) (ilti II assailed a- a Dogmatist. See el-— «■ ii. 4.U 
 note *.— H.
 
 490 
 
 ON THE INTELLECTUAL POWERS. 
 
 [essay vih. 
 
 ESSAY VIII. 
 
 OF TASTE. 
 
 CHAPTER I. 
 
 OF TASTE IN GENERAL. 
 
 That power of the mind by which we 
 are capable of discerning and relishing the 
 beauties of Nature, and whatever is excel- 
 lent in the fine arts, is called taste. 
 
 Tlie external sense of taste, by which we 
 distinguish and relish the various kinds of 
 food, has given occasion to a metaphorical 
 application of its name to this internal 
 power of the mind, by which we perceive 
 what is beautiful and what is deformed or 
 defective in the various objects that we 
 contemplate. 
 
 Like the taste of the palate, it relishes 
 some things, is disgusted with others ; with 
 regard to many, is indifferent or dubious ; 
 and is considerably influenced by habit, by 
 associations, and by opinion. These obvious 
 analogies between external and internal 
 taste, have led men, in all ages, and in 
 all or most polished languages.* to give the 
 name of the external sense to this power of 
 discerning what is beautiful with pleasure, 
 and what is ugly and faulty in its kind with 
 disgust. [714] 
 
 In treating of this as an intellectual 
 power of the mind, I intend only to make 
 some observations, first on its nature, and 
 then on its objects. 
 
 1. In the external sense of taste, we are 
 led by reason and reflection to distinguish 
 between the agreeable sensation we feel, and 
 the quality in the object which occasions it. 
 Both have the same name, and on that ac- 
 count are apt to be confounded by the vulgar, 
 and even by philosophers. The sensation 
 I feel when I taste any sapid body is in my 
 mind ; but there is a real quality in the 
 body which is the cause of this sensation. 
 These two things have the same name in 
 language, not from any similitude in their 
 nature, but because the one is the sign of 
 the other, and because there is little occa- 
 sion in common life to distinguish them. 
 
 This was fully explained in treating of the 
 secondary qualities of bodies. The reason 
 cf taking notice of it now is, that the in- 
 ternal power of taste bears a great analogy 
 in this respect to the external. 
 
 When a beautiful object is before us, we 
 
 ♦ This is hardly correct.— H. 
 
 may distinguish the agreeable emotion it 
 produces in us, from the quality of the ob- 
 ject which causes that emotion. When I 
 hear an air in music that pleases me, I say, 
 it is fine, it is excellent. This excellence is 
 not in me ; it is in the music. But the 
 pleasure it gives is not in the music ; it is 
 in me. Perhaps I cannot say what it is in 
 the tune that pleases my ear, as I cannot 
 say what it is in a sapid body that pleases my 
 palate ; but there is a quality in the sapid 
 body which pleases my palate, and I call it 
 a delicious taste ; and there is a quality in 
 the tune that pleases my taste, and I call it 
 a fine or an excellent air. 
 
 This ought the rather to be observed, 
 because it is become a fashion among mo- 
 dern philosophers, to resolve all our percep- 
 tions into mere feelings or sensations in the 
 person that perceives, without anything 
 corresponding to those feelings in the ex- 
 ternal object. [715] According to those 
 philosophers, there is no heat in the fire, 
 no taste in a sapid body ; the taste and the 
 heat being only in the person that feels 
 them.* In like manner, there is no beauty 
 in any object whatsoever ; it is only a sens- 
 ation or feeling in the person that per- 
 ceives it. 
 
 The language and the common sense of 
 mankind contradict this theory. Even those 
 who hold it, find themselves obliged to use 
 a language that contradicts it. 1 had occa- 
 sion to shew, that there is no solid founda- 
 tion for it when applied to the secondary 
 qualities of body ; and the same arguments 
 shew equally, that it has no solid foundation 
 when applied to the beauty of objects, or to 
 any of those qualities that are perceived by 
 a good taste. 
 
 But, though some of the qualities that 
 please a good taste resemble the secondary 
 qualities of body, and therefore may be 
 called occult qualities, as we only feel their 
 effect, and have no more knowledge of the 
 cause, but that it is something which is 
 adapted by nature to produce that effect — 
 this is not always the case. 
 
 Our judgment of beauty is in many cases 
 more enlightened. A work of art may 
 appear beautiful to the most ignorant, even 
 to a child. It pleases, but he knows not 
 
 * But see, above, p. 205, b, note *, anc» p. 310 b, 
 iiote +.— H. 
 
 [714, 715]
 
 CHAP. I. ] 
 
 OF TASTE IN GENERAL. 
 
 491 
 
 why. To one who understands it perfectly, 
 and perceives how every part is fitted with 
 exact judgment to its end, the beauty is not 
 mysterious ; it is perfectly coniprehendeJ ; 
 and he knows wherein it consists, as well 
 as how it afiects him. 
 
 2. "We may observe, that, though all the 
 tastes- we perceive by the palate are either 
 agreeable or disagreeable, or indifferent ; 
 yet, among those that are agreeable, there 
 is great diversity, not in degree only, but in 
 kind. And, as we have not generical names 
 for all the difterent kinds of taste, we dis- 
 tinguish them by the bodies in which they 
 are found. [716] 
 
 In like manner, all the objects of our 
 internal taste are either beautiful, or dis- 
 agreeable, or inditierent ; yet of beauty there 
 is a great diversity, not only of degree, but 
 of kind. The beauty of a demonstration, 
 the beauty of a poem, the beauty of a palace, 
 the beauty of a piece of niHsic, the beauty 
 of a fine woman, and many more that might 
 be named, are different kinds of beauty ; 
 and we have no names to distinguish them 
 but the names of the different objects to 
 which they belong. 
 
 As there is such diversity in the kinds of 
 beauty as well as in the degrees, we need 
 not think it strange that philosophers have 
 gone into diff"erent systems in analysing it, 
 and enumerating its simple ingredients. 
 They have made many just observations on 
 the subject ; but, from the love of simplicity, 
 have reduced it to fewer principles than the 
 nature of the thing will permit, having had 
 in their eye some particular kinds of beauty, 
 while they overlooked others. 
 
 There are moral beauties as well as na- 
 tural ; beauties in the objects of sense, and 
 in intellectual objects ; in the works of men, 
 and in the works of God ; in things inani- 
 mate, in brute animals, and in rational 
 beings ; in the constitution of the body of 
 man, and in the constitution of his miml. 
 'I'licre is lio real excellence which has not 
 its beauty to a diHcerning eye, when ]ilaced 
 in a proper point of view ; and it is as diffi- 
 cult to enumerate the ingredients of beauty 
 as the ingredients of real excellence. 
 
 3. The taste of the palate may be accounted 
 most just and perfect, when wc relish tlie 
 tilings that are fit for the nourishment of 
 the body, and ai-e disgusted witii things of 
 a contrary nature. 'J"he manifest intention 
 of nature in giving us this sense, is, that 
 we may discern what it is fit for us to eat 
 and to drink, and what it is not. Brute 
 animals are directed in the choice of their 
 food merely by their taste. |7'71 I-e<l by 
 this guide, they choose the food that nature 
 intended lor tliem, and K('ldom mak(! mis- 
 takes, unless they be pinched liy hunger, or 
 deceived by artificial compositions. Jn in- 
 fants likewise the taste is commonly sound 
 [716-71HJ 
 
 and uncorrupted, and of the simple produc- 
 tions of nature they relish the things that 
 are most wholesome. 
 
 In like manner, our internal taste ought 
 to be accounted most just and perfect, when 
 we are pleased with things that are nu)st 
 excellent in their kind, and displeased with 
 the contrary. The intention of nature is 
 no less evident in this internal taste than 
 in the external. Every excellence has a 
 real beauty and charm that makes it an 
 agreeable object to those who have the 
 faculty of discerning its beauty ; and this 
 faculty is what we call a good taste. 
 
 A man who, by any disorder in his mental 
 powers, or by bad habits, has contracted a 
 relish for what has no real excellence, or 
 what is deformed and defective, has a de- 
 praved taste, like one who finds a more 
 agreeable relish in ashes or cinders than in 
 the most wholesome food. As we must ac- 
 knowledge the taste of the palate to be de- 
 praved in this case, there is tiiesame reason 
 to think the taste of the mind depraved in 
 the other. 
 
 There is therefore a just and rational 
 taste, and there is a depraved and corrupted 
 taste. For it is too evident, that, by bad 
 education, bad habits, and wrong associa- 
 tions, men may acquire a relish for nasti- 
 ness, for rudeness, and ill-breeding, and for 
 many other deformities. To say that such 
 a taste is not vitiated, is no less absurd than 
 to say, that the sickly girl who delights in 
 eating charcoal and tobacco-pipes, has as 
 just and natural a taste as when she is in 
 perfect health. 
 
 4. The force of custom, of fancy, and of 
 casual associations, is very great both upon 
 the external and internal taste. An E>ki- 
 maux can regale himself with a draught of 
 whale-oil, and a Canadian can feast upon a 
 dog. A Kamschatkadale lives upon jiutrid 
 fish, and is sometimes reduced to eat the 
 bark of trees. The ta^te of rum, or of green 
 tea, is at first as nauseous as that of ijieca- 
 cuan, to some persons, who may be brought 
 by use to relish what they once found so 
 disagreeable. [7 Iff] 
 
 When we see such varieties in the taste 
 of the palate produced Vjy custom and as- 
 sociations, and some, perhaps, by constitu- 
 tion, we may be the less surprised that the 
 same causes should [inxhice like varieties 
 in the taste of beauty ; that the African 
 should esteem thick lijis and a flat nose; 
 that other nations should draw out their 
 ears, till they hang over their shoulders | 
 that in one nation ladies should jiaint their 
 faces, and in another should nudie them 
 shine with grease. 
 
 T). 'i'hose who conceive that there is no 
 standard in nature by which taste nwiy be 
 regulated, and tiiat the connnon proverb, 
 " That there ought to be no dispute about
 
 492 
 
 ON THE INTELLECTUAL rOWEIlS. 
 
 [^KSSA 
 
 Y Vlll. 
 
 taste," is to be taken in the utmost latitude, 
 go upon slender and insufficient ground. 
 The same arguments might be used with 
 equal force against any standard of truth. 
 
 Whole nations by the force of prejudice 
 are brought to believe the grossest absurdi- 
 ties ; and why should it be thought that the 
 taste is less capable of being perverted than 
 the judgment ? It must indeed be acknow- 
 ledged, that men differ more in the faculty 
 of taste than in what we commonly call 
 judgment ; and therefore it may be expected 
 that they should be more liable to have their 
 taste corrupted in matters of beauty and 
 deformity, than their judgment in matters 
 of truth and error. 
 
 If we make due allowance for this, we 
 shall see that it is as easy to account for 
 the variety of tastes, though there be in 
 nature a standard of true beauty, and con- 
 sequently of good taste, as it is to account 
 for the variety and contrariety of opinions, 
 tliough there be in nature a standard of 
 of truth, Hnd, consequently, of right judg- 
 ment. [719] 
 
 6. Nay, if we speak accurately and 
 strictly, we shall find that, in every opera- 
 tion of taste, there is judgment implied. 
 
 When a man pronounces a poem or a 
 palace to be beautiful, he affirms something 
 of that poem or that palace ; and every 
 affirmation or denial expresses judgment. 
 For we cannot better define judgment, than 
 by saying that it is an affirmation or denial 
 of one thing concerning another. I had 
 occasion to shew, when treating of judg- 
 nient, that it is implied in every perception 
 of our external senses. There is an imme- 
 diate conviction and belief of the existence 
 of the quality perceived, whether it be 
 colour, or sound, or figure ; and the same 
 thing holds in the perception of beauty or 
 deformity. 
 
 If it be said that the perception of beauty 
 is merely a feeling in the mind that per- 
 ceives, without any belief of excellence in 
 the object, the necessary consequence of 
 this opinion is, that when I say Virgil's 
 " Georgics" is a beautiful poem, I mean not 
 to say anything of the poem, but only some- 
 thing concerning myself and my feelings. 
 Why should I use a language that expresses 
 the contrary of what I mean ? 
 
 My language, according to the necessary 
 rules of construction, can bear no other 
 meaning but this, that there is something 
 in the poem, and not in me, which I call 
 beauty. Even those who hold beauty to 
 be merely a feeling in the person that per- 
 Goives it, find themselves under a necessity 
 of expressing themselves as if beauty were 
 s^olely a quality of the object, and not of 
 the percipient. 
 
 No reason can be given why all man- 
 kind should express themselves thus, but that 
 they believe what they say. It is there- 
 fore contrary to the universal sense of 
 mankind, expressed by their language, that 
 beauty is not really in the object, but is 
 merely a feeling in the person who is said 
 to perceive it. Philosophers should be very 
 cautious in opposing the common sense 
 of mankind ; for, when they do, they rarely 
 miss going wrong. [720] 
 
 Our judgment of beauty is not indeed a 
 dry and unaffccting judgment, like that- of 
 a mathematical or metaphysical truth. By 
 the constitution of our nature, it is accom- 
 panied with an agreeble feeling or emotion, 
 for which we have no other name but the 
 sense of beauty. This sense of beauty, like 
 the perceptions of our other senses, implies 
 not only a feeling, but an opinion of some 
 quality in the object which occasions that 
 feeling. 
 
 In objects that please the taste, we always 
 judge that there is some real excellence, 
 some superiority to those that do not 
 please. In some cases, that f-uperior ex- 
 cellence is distinctly perceived, and can 
 be pointed out ; in other cases, we have 
 only a general notion of some excellence 
 \\ Inch we cannot describe. Beauties of the 
 former kind may be compared to the 
 primary qualities jierceived by the external 
 .senses ; those of the latter kind, to the 
 secondary. 
 
 7. Beauty or deformity in an object, i-e- 
 sults from its nature or structure. To per- 
 ceive the beauty, therefore, we must per- 
 ceive the nature or structure from which it 
 results. In this the internal sense differs 
 from the external. Our external senses 
 may discover qualities which do not depend 
 upon any antecedent perception. Thus, I 
 can hear the sound of a bell, though I never 
 perceived anything else belonging to it. 
 But it is impossible to perceive the beauty 
 of an object without perceiving the object, 
 or, at least, conceiving it. On this account, 
 Dr Hutcheson called the senses of beauty 
 and harmony reflex or secondary senses ; 
 because the beauty cannot be perceived 
 unless the object be perceived by some other 
 power of the mind. Thus, the sense of 
 harmony and melody in sounds supjioses 
 the external sense of hearing, and is a kind 
 of secondary to it. A man born deaf may 
 be a good judge of beauties of another kind, 
 but can have no notion of melody or har- 
 mony. The like may be said of beau- 
 ties in colouring and in figure, which can 
 never be perceived without the senses by 
 which colour and figure are perceived. 
 [721] 
 
 [7 19-721 J
 
 CHAP. II.] 
 
 OF NOVELTY. 
 
 493 
 
 CHAPTER II. 
 
 OK THK OBJECTS OF TASTE ; AND, FIRST, OF 
 NOVELTV. 
 
 A PHILOSOPHICAL analj'sis of the objects 
 of taste is like applying the anatomical knife 
 to a fine face. The design of the philoso- 
 pher, as well as of the anatomist, is not to 
 gratify taste, but to imjirove knowledge. 
 The reader ought to be aware of this, that 
 he may not entertain an expectation in 
 which he will be disappointed. 
 
 By the objects of taste, I mean those 
 qualities or attributes of things wliich are, 
 by Nature, adapted to please a good taste. 
 Mr Addison, and Dr Akenside after him, 
 have reduced them to three— to wit, novelty, 
 (/landeur, and hcauli/. This division is 
 sufficient for all I intend to say upon the 
 subject, and therefore I shall adopt it — 
 observing only, that beauty is often taken 
 in so extensive a sense as to comprehend 
 all the objects of taste ; yet all the authors 
 I have met with, who have given a division 
 of the objects of taste, make beauty one 
 species. 
 
 I take tTie reason of this to be, that we 
 have specific names for some of the quali- 
 ties that please the taste, but not for all ; 
 and therefore all those fall under the gene- 
 ral name of beauty, for which there is no 
 specific name in the division. 
 
 There are, indeed, so ma'iy species of 
 beauty, that it would be as difficult to enu- 
 merate them perfectly, as to enumerate all 
 the tastes we perceive by the palate. Nor 
 does there appear to me sufficient reason 
 for making, as some very ingenious authors 
 have done, as many dift'ei-ent internal senses 
 as tiiere are different species of beauty or 
 deformity. [722] 
 
 The division of our external senses is 
 taken from the organs of perception, and 
 not from the qualities perceived. We have 
 not the same means of dividing the inter- 
 nal ; because, though some kinds of beauty 
 belong only to objects of the eye, and others 
 to objects of the ear, there are many wliich 
 we cannot refer to any bodily organ ; and 
 therefore I conceive every division that has 
 been made of our internal senses to be in 
 some degree arbitrary. They may be made 
 more or fewer, according as we have dis- 
 tinct names for the various kinds of beauty 
 and deformity ; and I suspect the most 
 copious languages have not names for them 
 all. 
 
 Novelty is not properly a quality of the 
 tiling to which we attribute it, far less is 
 it a sensation in the mind to which it is 
 new; it is a relation wliich the thing has 
 to the knowledge of tho person. What is 
 new to one man, may not be so to another ; 
 [ 722, 72.3] 
 
 what is new this moment, niAy be familiar 
 to the same person some time hence. When 
 an object is first brought to our know- 
 ledge, it is new, wliether it be agreeable 
 or not. 
 
 It is evident, therefore, with regard to 
 novelty, (whatever may be said of other 
 objects of taste,) that it is not merely a 
 sensatioH in the mind of him to whom the 
 thing is new ; it is a real relation which 
 the thing has to his knowledge at that 
 time. 
 
 But we are so constituted, that what is 
 new to us commonly gives pleasure upon 
 that account, if it be not in itself disagree- 
 able. It rouses our attention, and occa- 
 sions an agreeable exertion of our facul- 
 ties. 
 
 The pleasure we receive from novelty in 
 objects has so great infiuence in human 
 life, that it well deserves the attention of 
 philosophers ; and several ingenious authors 
 — particularly Dr Gerard, in his " Essay on 
 Taste" — have, I think, successfully account- 
 ed for it, from the principles of the human 
 constitution. [723] 
 
 We can perhaps conceive a being so 
 made, that his hajipiness consists in a con- 
 tinuance of the same unvaried sensations or 
 feelings, without any active exertion on his 
 part. Whether this be possible or not, it 
 is evident that man is not such a being ; 
 his good consists in the vigorous exertion 
 of his active and intellective powers upon 
 their proper objects ; he is made for action 
 and progress, and cannot be happy without 
 it ; liis enjoyments seem to be given by 
 Nature, not so much for their own sake, as 
 to encourage the exercise of his various 
 powers. That tranquillity of soul in which 
 some place human happiness, is not a dead 
 test, but a regular progressive motion. 
 
 Such is the constitution of man by the 
 apjjoiutment of Nature. This constitution 
 is perhaps a part of the imperfection of our 
 nature ; but it is wisely adapted to our 
 state, which is not intended to be stationary, 
 but progressive, 'i'lie eye is not satiated 
 with seeing, nor the ear with liearing ; 
 something is always wanted. Desire and 
 hope never cease, but remain to spur us c ii 
 to something yet to be acquired ; and, if 
 they could cease, human happiness must 
 end with them. That our desire and hope 
 be properly directed, is our part; that tiiey 
 can never be extinguished, is the work of 
 Nature. 
 
 It is this that makes human life so busy 
 a scene. ]Man must be doing something, 
 good or bad, trifiing or imiuirtant ; and be 
 must vary tho employment of his facul- 
 ties, or their exercise will become languid, 
 and the pleasure that attends it sicken of 
 course. 
 
 Tlie notions of enjoyment, and of lutivity,
 
 494 
 
 ON THE INTELLECTUAL POWERS. [essay viii. 
 
 considered abstractly, are no doubt very 
 different, and we cannot perceive a necessary 
 connection between them. But, in our con- 
 stitution, they are so connected by the 
 wisdom of Nature, that they nmst go hand 
 in hand ; and the first must be led and 
 supported by the last. [724] 
 
 An object at first, perhaps, gave much 
 pleasure, while attention was directed to it 
 with vigour. But attention cannot be long 
 confined to one unvaried object, nor can it 
 be carried round in the same narrow circle. 
 Curiosity is a capital principle in the human 
 constitution, and its food must be what is 
 in some respect new. What is said of the 
 Athenians may, in some degree, be applied 
 to all mankind. That their time is spent 
 in hearing, or telling, or doing some new 
 thing. 
 
 Into this part of the human constitution, 
 I think, we may resolve the pleasure we 
 have from novelty in objects. 
 
 Curiosity is commonly strongest in child- 
 ren and in young persons, arid accordingly 
 novelty pleases them most. In all ages, in 
 proportion as novelty gratifies curiosity, and 
 occasions a vigorous exertion of any of our 
 mental powers in attending to the new ob- 
 ject, in the same proportion it gives plea- 
 sure. In advanced life, the indolent and 
 inactive have the strongest passion for news, 
 as a relief from a painful vacuity of thought. 
 
 But the pleasure derived from new objects, 
 in many cases, is not owing solely or chiefly 
 to their being new, but to some other cir- 
 cumstance that gives them value. The new 
 fashion in dress, furniture, equipage, and 
 other accommodations of life, gives plea- 
 sure, not so much, as I apprehend, because 
 it is new, as because it is a sign of rank, 
 and distinguishes a man from the vulgar. 
 
 In some things novelty is due, and the 
 want of it a real imperfection. Thus, if an 
 author adds to the number of books with 
 which the public is already overloaded, we 
 expect from hira something new ; and, if he 
 says nothing but what has been said before 
 in as agreeable a manner, we are justly 
 disgusted. [725] 
 
 When novelty is altogether separated 
 from the conception of worth and utility, it 
 makes but a slight impression upon a truly 
 correct taste. Every discovery in nature, 
 in the arts, and in the sciences, has a real 
 value, and gives a rational pleasure to a 
 good taste. But things that have nothing 
 to recommend them but novelty, are fit 
 only to eiitertain children, or those who are 
 distressed from a vacuity of thought. This 
 quality of objects may therefore be com- 
 pared to the cypher in arithmetic, which 
 adds greatly to the value of significant 
 figures ; but, when put by itself, signifies 
 nothing at all. 
 
 CHAPTER IIL 
 
 OF GRANDEUR. 
 
 The qualities which please the taste are 
 not more various in themselves than are 
 the emotions and feelings with which they 
 affect our minds. 
 
 Things new and uncommon affect us with 
 a pleasing surprise, which rouses and invi- 
 gorates our attention to the object. But 
 this emotion soon flags, if there is nothing 
 but novelty to give it continuance, and 
 leaves no effect upon the mind. 
 
 The emotion raised by grand objects is 
 awful, solemn, and serious. 
 
 Of all objects of contemplation, the Su- 
 preme Being, is the most grand. His 
 eternity, his immensity, his irresistible power, 
 his infinite knowledge and unerring wisdom, 
 his inflexible justice and rectitude, his su- 
 preme government, conducting all the 
 movements of this vast universe to the no- 
 blest ends and in the wisest manner — are 
 objects which fill the utmost capacity of the 
 soul, and reach far beyond its comprehension. 
 
 The emotion which this grandest of all 
 objects raises in the human mind, is what 
 we call devotion ; a serious recollected tem- 
 per, which inspires magnanimity, and dis- 
 poses to the most heroic acts of virtue. [726] 
 
 The emotion produced by other objects 
 whicli may be called grand, though iu an 
 inferior degree, is, in its nature and in its 
 effects, similar to that of devotion. It dis- 
 poses to seriousness, elevates the mind 
 above its usual state, to a kind of enthusi- 
 asm, and inspires magnanimity, and a con- 
 tempt of what is mean. 
 
 Such, I conceive, is the emotion which 
 the contemplation of grand objects raises in 
 us. We are next to consider what this 
 grandeur in objects is. 
 
 To me it seems to be nothing else but 
 such a degree of excellence, in one kind or 
 another, as merits our admiration. 
 
 There are some attributes of mind which 
 have a real and intrinsic excellence, com- 
 pared with their contraries, and which, in 
 every degree, are the natural objects of 
 esteem, but, in an uncommon degree, are ob- 
 jects of admiration. We put a value upon 
 them because they are intrinsically valuable 
 and excellent. 
 
 The spirit of modern philosophy would 
 indeed lead us to think, that the worth and 
 value we put upon things is only a sensation 
 in our minds, and not anythins inherent in 
 the object ; and that we might have been so 
 constituted as to put the highest value upon 
 the things which we now despise, and to 
 despise the qualities which we now highly 
 esteem. 
 
 [7^4-726]
 
 niiAF, 
 
 III.] 
 
 OF GRANDPXR. 
 
 495 
 
 It gives me pleasure to observe, that Dr 
 Price, in his " Review of the Questions 
 concerning Morals," strenuously opposes 
 this opinion, as well as that which resolves 
 moral right and wrong into a sensation iu 
 the minii of the spectator. That judicious 
 author saw the consequences which these 
 opinions draw after them, and has traced 
 them to their source — to wit, the account 
 given by Mr Locke, and adopted by the gen- 
 erality uf modern philosophers, of the ori- 
 gin of all our ideas, which account he shews 
 to be very defective. [7-7] 
 
 This pronenessto resolve everything into 
 feelings and sensations, is an extreme into 
 which we have been led by the desire of 
 avoidmg an opposite extreme, as common 
 in the ancient [>hilosophy. 
 
 At first, me are prone by nature and by 
 habit to give all their attention to things 
 external. Their notions of the mind, and 
 its operations, are formed from some analogy 
 they bear to objects of sense ; and an ex- 
 ternal existence is ascribed to things which 
 are only conceptions or feelings of the 
 mind. 
 
 This spirit prevailed much in the philo- 
 sophy both of Plato and of Aristotle, and 
 produced the mysterious notions of eternal 
 and self-existent ideas, of materia prima, of 
 substantial forms, and others of the like 
 nature. 
 
 From the time of Des Cartes, philosophy 
 took a contrary turn- That great man dis- 
 covered, that many things supposed to have 
 an external existence, were only conceptions 
 or feelings of the mind. This track has 
 been pursued by his successors to such an 
 extreme as to resolve everything into sens- 
 ations, feelings, and ideas in the mind, and 
 to leave nothing external at all. 
 
 The Peripatetics thought that heat and 
 cold which we feel to be qualities of external 
 objects. The moderns make heat and cold 
 to be sensations only, and allow no real 
 quality of body to be called by that name : 
 and tile same judgment they have formed 
 with regard to all secondary qualities. 
 
 So far Des Cartes and Mr Locke went. 
 Their successors being put into this track 
 of converting into feelings things that were 
 believed to have an external existence, found 
 that exten-ion, solidity, figure, and all the 
 primary qualities of body, are sensations or 
 feelings of the mind ; and that the material 
 world is a phjjenomenon only, and has no 
 existence but in our mind. [728] 
 
 It was then a verynatural progress to con- 
 ceive, that beauty, harmony, and grandeur, 
 the objects of taste, as well as right and 
 wrong, the objects of the moral faculty, are 
 nothing but ieelings of the mind. 
 
 Those who are ycquaiiitcd with tl'.e 
 writings of modern philosophers, can easily 
 trace this doctrine of feelings, from Des 
 [727-729] 
 
 Cartes down to Mr Hume, who put the 
 finishing stroke to it, by making trutJi and 
 error to be feelings of the muid, and belief 
 to be an operation of the sensitive part of 
 our nature. 
 
 To return to our subject, if we liearken 
 to the dictates of common sense, we must be 
 convinced that there is real excellence in 
 some things, whatever our feelings or our 
 constitution be. 
 
 It depends no doubt upon our constitu- 
 tion, whether we do or do not perceive ex- 
 cellence where it really is : but the object 
 has its excellence from its own constitution, 
 and not from ours. 
 
 The common judgment of mankind in this 
 matter sufKcieutly appears in tlie language 
 of all nations, which uniformly ascribes ex- 
 cellence, grandeur, and beauty to the object, 
 and not to the mind that perceives it. And 
 I believe in this, as in most other things, 
 we shall find the common judgment of man- 
 kind and true philosophy not to be at va- 
 riance. 
 
 Is not power in its nature more excel- 
 lent than weakness ; knowledge than igno- 
 rance ; wisdom than folly ; fortitude than 
 pusillanimity ? 
 
 Is there no intrinsic excellence in self- 
 command, in generosity, in public sjjirit ? 
 Is not friendship a better affection of mind 
 than hatred, a noble emulation than envy ? 
 [12i)] 
 
 Let us suppose, \i possible, a being so 
 constituted as to have a high respect for 
 ignorance, weakness, and folly ; to venerate 
 cowardice, malice, and envy, and to hold 
 the contrary qualities in contempt ; to have 
 an esteem for lying and falsehood ; and to 
 love most those who imposed upon him, 
 and used him worst. Could we believe 
 such a constitution to be anything else than 
 madness and delirium ? It is impossible. 
 We can as easily conceive a constitution, 
 by which one should perceive two and three 
 to make fifteen, or a part to be greater than 
 the whole. 
 
 Every one who attends to the operations 
 (if his own mind will find it to be certainly 
 true, as it is the connnon liclief of mankind, 
 that esteem is led by opinion, and that every 
 person draws our esteem, as far only as he 
 a])piars either to reason or fancy to be 
 amiable and worthy. 
 
 There is therefure a real intrinsic excel- 
 lence in some qualities of mind, as in power, 
 knowledge, wisdom, virtue, magnanimity. 
 These, in every degree, merit esteem ; but 
 in an unconnnon degree they merit admir- 
 ation ; and that which mcrita admiration 
 we call grand. 
 
 In the contemplation of unconmion ex- 
 cellence, tln! mind feels a nol.le enthusiasm, 
 which disposes it to tho imitation of what it 
 admires.
 
 496 
 
 ON THE INTELLECTUAL POWERS. 
 
 [essay VIII. 
 
 When we contemplate the character of 
 Cato — his greatness of soul, his superiority 
 to pleasure, to toil, and to danger; his ar- 
 derit zeal for the liberty of his country ; 
 when we see him standing unmoved in mis- 
 fortunes, the last pillar of the liberty of 
 Rome, and falling nobly in his country's 
 ruin — who would not wish to be Cato rather 
 than Ctesar in all his triumph ? [730] 
 
 Such a spectacle of a great po\i1 strug- 
 gling with misfortune, Seneca thought not 
 unworthy of the attention of Jupiter him- 
 self, " Ecce spectaculum Deo diguuni, ad 
 quod respiciat Jupiter suo operi intentus, 
 vir fortis cum mala fortuna compositus." 
 
 As the Deity is, of all objects of thought, 
 the most grand, the descriptions given in 
 holy writ of his attributes and works, even 
 when clothed in simple expression, are 
 acknowledged to be sublime. The expres- 
 sion of Moses, " And God said. Let there 
 be light, and there was light,"* has not 
 escaped the notice of Longinus, a Heathen 
 critic, as an example of the sublime. 
 
 What we call sublime in description, or 
 in speech of any kind, is a proper expres- 
 sion of the admiration and enthusiasm which 
 the subject produces in the mind of the 
 speaker. If this admiration and enthu- 
 siasm appears to be just, it carries the 
 hearer along with it involuntarily, and by 
 a kind of violence rather than by cool con- 
 viction : for no passions are so infectious as 
 those which hold of enthusiasm. 
 
 But, on the other hand, if the passion of 
 the speaker appears to be in no degree jus- 
 tified by the subject or the occasion, it pro- 
 duces in the judicious hearer no other emo- 
 tion but ridicule and contempt. 
 
 The true sublime cannot be produced 
 solely by art in the composition ; it must 
 take its rise from grandeur in the subject, 
 and a corresponding emotion raised in the 
 mind of the speaker. A proper exhibition 
 of these, thoiigh it should be artless, is 
 irresistible, like fire thrown into the midst 
 of combustible matter. [731] 
 
 When we contemplate the earth, the sea, 
 the planetary system, the universe, these 
 are vast objects ; it requires a stretch of 
 imagination to grasp them in our minds. 
 But they appear truly grand, and merit the 
 highest admiration, when we consider them 
 as the work of God, who, in the simple 
 style of scripture, stretched out the heavens, 
 and laid the foundation of the earth ; or, in 
 the poetical language of Milton — 
 
 " In his hand 
 He took the golden cortipasses, prepar'd 
 In God's eternal storp, to ciirumscribe 
 Thi> univtr,-e and all created thii.gs. 
 One fool he ceatr'd, and the f ther turn'd 
 Round thro' the vast piofui.dity obscure; 
 
 * Better translated — " Be there 1 ght, and light 
 there was " — H. 
 
 And said, Thus far extend, thus far thy bound*, 
 This be thy juat circumference, O world." 
 
 When we contemplate the world of Epi- 
 curus, and conceive the universe to be a 
 fortuitous jumble of atoms, there is nothing 
 grand in this idea. The clashing of atoms 
 by blind chance has nothing in it fit to raise 
 our conceptions, or to elevate the mind. 
 But the regular structure of a vast system 
 of beings, produced by creating power, and 
 governed by the best laws which perfect 
 wisdom and goodness could contrive, is a 
 spectacle which elevates the understanding, 
 and fills the soul with devout admiration. 
 
 A great work is a work of great power, 
 great wisdom, and great goodness, well con- 
 trived for some important end. But power, 
 wisdom, and goodness, are properly the at- 
 tributes of mind only. They are ascribed to 
 the work figuratively, but are really inherent 
 in the author : and by the same figure, the 
 grandeur is ascribed to the work, but is 
 properly inherent in the mind that made it. 
 
 Some figures of speech are so natural and 
 so common in all languages, that we are led 
 to think them literal and proper expressions. 
 Thus an action is called brave, virtuous, 
 generous ; but it is evident, that valour, 
 virtue, generosity, are the attributes of per- 
 sons only, and not of actions. In the action 
 considered abstractly, there is neither val- 
 our, nor virtue, nor generosity. The same 
 action done from a different motive may 
 deserve none of those epithets. [732] The 
 change in this case is not in the action, but 
 in the agent ; yet, in all languages, generosity 
 and other moral qualities are ascribed to 
 actions. By a figure, we assign to the effect 
 a quality which is inherent only in the 
 cause. 
 
 By the same figure, we ascribe to a work 
 that grandeur which properly is inherent in 
 the mind of the author. 
 
 When we consider the " Iliad" as the 
 work of the poet, its sublimity was really 
 in the mind of Homer. He conceived 
 great characters, great actions, and great 
 events, in a manner suitable to their nature, 
 and with those emotions which they are 
 naturally fitted to produce ; and he conveys 
 his conceptions and his emotions by the 
 most proper signs. The grandeur of his 
 thoughts is reflected to our eye by his work, 
 and, therefore, it is justly called a grand 
 work. 
 
 When we consider the things presented 
 to our mind in the " Iliad" witliout regard 
 to the poet, the grandeur is properly in 
 Hector and Achilles, and the other great 
 personages, human and divine, brought 
 upon the stage. 
 
 Next to the Deity and his works, we ad- 
 mire great talents and heroic virtue in men, 
 wliether represented in history or in fiction. 
 The virtues of Cato, Aristides, Socrates, 
 
 [730-732]
 
 <iiAP. m 
 
 •] 
 
 OF (JRANDEUR. 
 
 45) 
 
 Marcus Aurelius, are truly graml. Extra- 
 t)rdinary talents and genius, whether in 
 poets, orators, philosophers, or lawgivers, are 
 objects of admiration, and therefore grand. 
 We fiiid writers of taste seized with a kind 
 of enthusiasm in the description of such 
 personages. 
 
 What a grand idea does Virgil give of the 
 power of eloquence, when he compares tlie 
 tempest of the sea, suddenly calmed by the 
 command of Neptune, to a furious sedition 
 in a great city, quelled at once by a man of 
 authority and eloquence. [733] 
 
 " Sic ait, ac dicto citius tiimida cequora placat : 
 Ac veluti raagno in populo, si forte coorta e.-t 
 Seditio, siEvitque animis ignobile vulgus ; 
 Jariique faces et saxa volant, furor anna ministrat ; 
 'I'um pictite gravem, et meritis, si forte virum quern 
 Ciin>pexere, silent, arrectisque auribus adstant. 
 Ule regit dictis animos, et peclora mulcet. 
 Sic cunctus pelagi cecidit fragor." 
 
 The wonderful genius of Sir Isaac New- 
 ton, and his sagacity in discovering the laws 
 of Nature, is admirably expressed in that 
 short but sublime epitaph by Pope : — 
 
 " Nature and Nature's laws lay hid in night ; 
 God said. Let Newton be — and all was light." 
 
 Hitherto we have found grandeur only in 
 qualities of mind ; but, it may be asked, Is 
 there no real grandeur in material objects ? 
 
 It will, perhaps, appear extravagant to 
 deny that there is ; yet it deserves to be 
 considered, whether all the grandeur we 
 ascribe to objects of sense be not derived 
 from something intellectual, of which they 
 are the effects or signs, or to which they bear 
 some relation or analogy. 
 
 Besides the relations of effect and cause, 
 of sign and thing signified, there are innu- 
 merable similitudes and analogies between 
 things of very different nature, which lead 
 us to connect them in our imagination, and 
 to ascribe to the one what properly belongs 
 to the other. 
 
 Every metaphor in language is an instance 
 of this ; and it must be remembered, that a 
 very great part of language, which we now 
 account proper, wasoriginallymetaphorical ; 
 for the metapliorical meaning becomes the 
 proper, as soon as it becomes the most 
 usual ; much more, when that which was at 
 first the proper meaning falls into disuse. 
 [734] 
 
 The poverty of language, no doubt, con- 
 tributes in part to the use of metaphor; 
 and, therefore, we find the most barren and 
 uncultivate<l languages the most metaphori- 
 cal, lint the most copious language may 
 be called barren, compared with the fertility 
 of human conceptions, andean never, with- 
 out the use of figures, keep pace with the 
 varii-ty of their delicate modificationfi. 
 
 But another cause of the use of metaphor 
 
 is, that we find pleasure in discovering rchi- 
 
 tions, similitudes, analogies, and even cou- 
 
 traets, that are not obvious to every eye. 
 
 733-7.3.J] 
 
 All figurative speech presents something of 
 this kind ; and the beauty of poetical lan- 
 guage seems to be derived in a great mea- 
 sure from this source. 
 
 Of all figurative language, that is the most 
 common, the most natural, and the most 
 agreeable, which either gives a body, if we 
 may so speak, to things intellectual, and 
 clothes them with visible qualities; orwhich, 
 on the other hand, gives intellectual quaUties 
 to the objects of sense. 
 
 To beings of more exalted faculties, intel- 
 lectual objects may, perhaps, appear to most 
 advantage in their naked simplicity. But 
 we can hardly conceive them but by means 
 of some analogy they bear to the objects of 
 sense. The names we give them are almost 
 all metaphorical or analogical. 
 
 Thus, the names of grand and sublime, as 
 well as their opposites, mean and low, are 
 evidently borrowed from the dimensions of 
 body ; yet, it must be acknowledged, that 
 many things are truly grand and sublime, 
 to which we cannot ascribe the dimensions 
 of height and extension. 
 
 Some analogy there is, without doubt, be- 
 tween greatness of dimension, which is an 
 object of external sense, and that grandeur 
 which is an object of taste. On account of 
 this analogy, the last borrows its name from 
 the first ; and, the name being common, 
 leads us to conceive that there is something 
 common in the nature of the things. [735] 
 
 But we shall find many qualities of mind, 
 denoted by names taken from some quality 
 of body to which they have some analogy, 
 without anything common in their nature. 
 
 Sweetness and austerity, simplicity and 
 duplicity, rectitude and crookedness, are 
 names common to certain qualities of mind, 
 and to qualities of body to which they have 
 some analogy ; yet he would err greatly who 
 ascribed to a body that sweetness or that 
 simplicity which are the qualities of mind. 
 In like manner, greatness and meanness 
 are names common to qualities perceived 
 by the external sense, and to qualities 
 perceived by taste ; yet he may be in an 
 error, who ascribes to the objects of sense 
 that greatness or that meanness which is 
 only an object of taste. 
 
 As intellectual objects are made more 
 level to our api)rehension by giving them a 
 visible form ; so the objects of sense are 
 dignified aixl made more august, by ascrib- 
 ing to them intellectual qualities which have 
 some analogy to those thoy really j)ossess. 
 The sea rages, the sky lowers, the meadows 
 smile, the rivulets murnnir, the breezes 
 whisper, the soil is grateful or ungratefid — 
 such exjiressions are so familiar in coninion 
 language, that they are scarcely accounted 
 [loetical or figurative; but they give a kind 
 of dignity to inanimate oiijccts, and niuko 
 our conception i>\' ilieni more agreeable, 
 
 'J K
 
 498 
 
 ON TIIK INTELLECTUAL POWERS. 
 
 L^-- 
 
 SAY \ [II, 
 
 When we consider matter as an inert, 
 extended, divisible, and movable substance, 
 there seems to be nothing in these qualities 
 whicli we can call grand ; and when we ascribe 
 grandeur to any portion of matter, however 
 modified, may it not borrow this quality 
 from something intellectual, of which it is 
 the effect, or sign, or instrument, or to 
 which it bears some analogy ? or, perhaps, 
 because it produces in the mind an emotion 
 that has some resemblance to that admira- 
 tion which truly grand objects raise '■ [736] 
 
 A very elegant writer on the sublime and 
 beautiful,* makes everything grand or sub- 
 lime that is terrible. Might he not be led 
 to this by the similarity between dread and 
 admiration ? Both are grave and solemn 
 passions ; both make a strong impression 
 upon the mind ; and both are very infec- 
 tious. But they differ specifically, in this 
 respect, that admiration supposes some un- 
 common excellence in its object, which 
 dread does not. We may admire what we 
 see no reason to dread ; and we may dread 
 what we do not admire. In dread, there is 
 nothing of that enthusiasm which naturally 
 accompanies admiration, and is a chief in- 
 gredient of the emotion raised by what is 
 truly grand or sublime. 
 
 Upon the whole, I humbly apprehend 
 that true grandeur is such a degree of ex- 
 cellence as is fit to raise an enthusiastical 
 admiration ; that this grandeur is found, 
 originally and properly, in qualities of mind ; 
 that it is discerned, in objects of sense, only 
 by reflection, as the light we perceive in the 
 moon and planets is truly the light of the 
 sun ; and that those who look for grandeur 
 in mere matter, seek the living among the 
 dead. 
 
 If this be a mistake, it ought, at least, to 
 be granted, that the grandeur which we 
 perceive in qualities of mind, ought to have 
 a different name from that which belongs 
 properly to the objects of sense, as they are 
 very different in their nature, and produce 
 very different emotions in the mind of the 
 spectator. [737] 
 
 CHAPTER IV. 
 
 OF B»AUTV. 
 
 Beauty is found in things so various 
 and so very different in nature, that it is 
 difficult to say wherein it consists, or what 
 there can be common to all the objects in 
 which it is -found. 
 
 Of the objects of sense, we find beauty in 
 colour, in sound, in form, in motion. There 
 are beauties of speech, and beauties of 
 thought ; beauties in the arts, and in the 
 
 * Burke.— H. 
 
 sciences ; beauties in actions, in affections, 
 and in characters. 
 
 In things so different and bo unlike is 
 there any quality, the same in all, which we 
 may call by the name of beauty ? What 
 can it be that is common to the thouglit of 
 a mind and the form of a piece of matter, 
 to an abstract theorem and a stroke of wit ? 
 
 I am indeed unable to conceive any qua- 
 lity in all the different things that are called 
 beautiful, that is the same in them all. 
 There seems to be no identity, nor even 
 similarity, between the beauty of a theorem 
 and the beauty of a piece of music, though 
 both may be beautiful. The kinds of beauty 
 seem to be as various as the objects to which 
 it is ascribed. 
 
 But why should things so different be 
 called by the same name ? This cannot be 
 without a reason. If there be nothing com- 
 mon in the things themselves, they must 
 have some common relation to us, or to 
 something else, which leads us to give them 
 the same name. [738] 
 
 All the objects we call beautiful agree in 
 two things, which seem to concur in our 
 sense of beauty. First, When they are 
 perceived, or even imagined, they pi-oduce 
 a certain agreeable emotion or feeling in the 
 mind; and, secondly. This agreeable emotion 
 is accompanied with an opinion or belief of 
 their having some perfection or excellence 
 belonging to them. 
 
 Whether the pleasure we feel in contem- 
 plating beautiful objects may have any ne- 
 cessary connection with the belief of their 
 excellence, or whether that pleasure be con- 
 joined with this belief, by the good pleasure 
 only of our Maker, I will not determine. 
 The reader may see Dr Price's sentiments 
 upon this subject, which merit considera- 
 tion, in the second chapter of his " Review 
 of the Questions concerning Morals." 
 
 Though we may be able to conceive these 
 two ingredients of our sense of beauty dis- 
 joined, this affords no evidence that they 
 have no necessary connection. It has in- 
 deed been maintained, that whatever we can 
 conceive, is possible : but I endeavoured, 
 in treating of conception, to shew, that this 
 opinion, though very common, is a mistake. 
 There may be, and probably are, many 
 necessary connections of things in nature, 
 which we are too dim-sighted to discover. 
 
 The emotion produced by beautiful ob- 
 jects is gay and pleasant. It sweetens and 
 humanises the temper, is friendly to every 
 benevolent affection, and tends to allay 
 sullen and angry passions. It enlivens the 
 mind, and disposes it to other agreeable 
 emotions, such as those of love, hope, and 
 joy. It gives a value to the object, ab- 
 stracted from its utility. 
 
 In things that may be possessed as pro- 
 perty, beauty greatly enhances the price. 
 
 [T 36-738]
 
 ( IIAP IV 
 
 J 
 
 OF BEAUTY. 
 
 A beautiful dog or liorse, a beautiful coach 
 or house, a beautiful picture or prospect, is 
 valued by its owuer aud by others, not only 
 for its utility, but for its beauty. [739] 
 
 If the beautiful object be a person, his 
 company aud conversation are, on that ac- 
 count, the more agreeable, and we are dis- 
 posed to love aud esteem him. Even in a 
 perfect stranger, it is a powerful recom- 
 mendation, and disposes us to favour and 
 think well of him, if of our own sex, and 
 still more if of the other. 
 
 " There is nothing," says Mr Addison, 
 " that makes its way more directly to the soul 
 than beauty, which immediately diffuses a 
 secret satisfaction and complacence through 
 the imagination, and gives a finishing to 
 anything that is great and uncommon. 
 The very first discovery of it strikes the 
 mind with an inward joy, and spreads a 
 cheerfulness and delight through all its 
 faculties." 
 
 As w^e ascribe beauty, not only to per- 
 sons, but to inanimate things, we give the 
 name of love or liking to the emotion, which 
 beauty, in both these kinds of objects, 
 produces. It is evident, however, that 
 liking to a person is a very different affec- 
 tion of mind from liking to an inanimate 
 thing. The first always implies benevo- 
 lence ; but what is inanimate cannot be the 
 object of benevolence. The two affections, 
 however different, have a resemblance in 
 some respects ; and, on account of that 
 resemblance, have the same name. And 
 perhaps beauty, in these two different kinds 
 of objects, though it has one name, may be 
 as different in its nature as the emotions 
 which it produces in us. 
 
 Besides the agreeable emotion which 
 beautiful objects produce in the mind of 
 the spectator, they produce also an opuiion 
 or judgment of some perfection or excel- 
 lence in the object. This I take to be a 
 second ingredient in our sense of beauty, 
 though it seems not to be admitted by 
 modern philosophers. [740] 
 
 The ingenious Dr llutcheson, who per- 
 ceived some of the defects of Mr Locke's 
 system, and made very important improve- 
 ments upon it, seems to have been carried 
 away by it, in his notion of beauty. In 
 his " Inquiry concerning Beauty," § 1, 
 " Let it be observed," says he, "that in the 
 following papers, the word beauty is taken 
 for the idea raised in us, and the sense of 
 beauty for our power of receiving that idea." 
 And again — " Only let it be observed, that, 
 by absolute or original beauty, is not under- 
 stood any quality supposed to be in the 
 object which should, of itself, be beautiful, 
 without relation to any mind which per- 
 ceives it : for beauty, like other names of 
 sensible ideas, jiroperly denotes the per- 
 ception of some mind ; so cold, hot, Hweet, 
 [739-711] 
 
 bitter, denote the sensations in our minds, 
 to which, perhaps, there is no resemblance 
 in the objects which excite these ideas iii 
 U9 ; however, we generally imagine other- 
 wise. Were there no mind, with a sense 
 of beauty, to contemplate objects, I see not 
 how they could be called beautiful." 
 
 There is no doubt an analogy between 
 the external senses of touch and taste, and 
 the internal sense of beauty. This analogy 
 led Dr Hutcheson, and other modern phi"- 
 losophers, to apply to beauty what Des 
 Cartes and Locke had taught concerning 
 the secondary qualities perceived by the 
 external senses. 
 
 Mr Locke's doctrine concerning the se- 
 condary qualities of body, is not so much 
 an error in judgment as an abuse of words. 
 He distinguished very properly between 
 the sensations we have of heat and cold, 
 and that quality or structure in the body 
 which is adapted by Nature to produce 
 those sensations in us. He observed very 
 justly, that there can be no similitude be- 
 tween one of these and the other. They 
 have the relation of an effect to its cause, 
 but no similitude. This was a very just 
 and proper correction of the doctrine of the 
 Peripatetics, who taught, that all our sens- 
 ations are the very form and image of the 
 quality in the object by which they are 
 produced. [7-H] 
 
 What remained to be determined was, 
 whether the words, heat and cold, in com- 
 mon language, signify the sensations we 
 feel, or the qualities of the object which 
 are the cause of these sensations. Mr 
 Locke made heat and cold to signify only 
 the sensations we feel, and not the qualities 
 which are the cause of them. And in this, 
 1 apprehend, lay his mistake. For it is 
 evident, from the use oi laiiguage, that hot 
 and cold, sweet and bitter, are attributes of 
 external objects, and not of the person who 
 perceives them. Hence, it appears a mon- 
 strous paradox to say, there is no heat in 
 the fire, no sweetness in sugar ; but, when 
 explained accordmg to Mr Locke's meaning, 
 it is only, like most other paradoxes, an 
 abuse of words.* 
 
 The sense of" beauty may be analysed in 
 a manner very similar to the, sense of sweet- 
 ness. It is an agreeable feeling or emotion, 
 accompanied with an opinion or judgment 
 of some excellence in the object, which is 
 fitted by Nature to produce that feeling. 
 
 The feeling is, no doubt, in the mind, 
 and so also is the judgment we form of the 
 object : but this judgment, like all others*, 
 nnist be true or false. If it Ik^ a true judg- 
 ment, there is some rcid excellence in the 
 object. And the use of all languages shews 
 that the name of beauty belongs to this ex- 
 
 'r Sof aliovp, p. «05, b, note *.— 11. 
 \l K '-'
 
 500 
 
 ON THE INTELLECTUAL POWERS 
 
 [essay VIII. 
 
 rellence of the object, and not to the feel- 
 inf);s of the spectator. 
 
 To say that there is, in reality, no beauty 
 in those objects in which all men perceive 
 beauty, is to attribute to man fallacious 
 senses. But we have no ground to think 
 so disrespectfully of the Author of our 
 being ; the faculties he hath given us are 
 not fallacious ; nor is that beauty which 
 he hath so liberally diffused over all the 
 works of his hands, a mere fancy in us, but 
 a real excellence in his works, which express 
 the perfection of their Divine Author. 
 
 We have reason to believe, not only that 
 the beauties we see in nature are real, and 
 not fanciful, but that there are thousands 
 which our faculties are too dull to perceive. 
 We see many beauties, both of human and 
 divine art, which the brute animals are in- 
 capable of perceiving ; and superior beings 
 may excel us as far in their discernment of 
 true beauty as we excel the brutes. [742] 
 
 The man who is skilled in painting or 
 statuary sees more of the beauty of a fine 
 picture or statue than a common specta- 
 tor. The same thing holds in all the fine 
 arts. The most perfect works of art have 
 a beauty that strikes even the rude and ig- 
 norant ; but they see only a small part of 
 that beauty which is seen in such works by 
 those who understand them perfectly, and 
 can produce them. 
 
 This may be applied, with no less justice, 
 to the works of Nature. They have a 
 beauty that strikes even the ignorant and 
 inattentive. But the more we discover of 
 their structure, of their mutual relations, 
 and of the laws by which they are governed, 
 the greater beauty, and the more delightful 
 marks of art, wisdom, and goodness, we 
 discern. 
 
 Thus the expert anatomist sees number- 
 less beautiful contrivances in the structure 
 of the human body, which are unknown to 
 the ignorant. 
 
 Although the vulgar eye sees much beauty 
 in the face of the heavens, and in the various 
 motions and changes of the heavenly bodies, 
 the expert astronomer, who knows their 
 order and distances, their periods, the orbits 
 they describe in the vast regions of space, 
 and the simple and beautiful laws by which 
 their motions are governed, and all the 
 appearances of their stations, progressions, 
 and retrogradations, their eclipses, occulta- 
 tions, and transits are produced — sees a 
 beauty, order, and harmony reign through 
 the whole planetary system, which delights 
 the mind. The eclipses of the sun and 
 moon, and the blazing tails of comets, 
 which strike terror into barbarous nations, 
 furnish the most pleasing entertainment to 
 his eye, and a feast to his understanding. 
 [743] 
 
 In every part of Nature's works, there 
 
 are numberless beauties, which, on account 
 of our ignorance, we are unable to perceive- 
 Superior beings may see more than we ; but 
 He only who made them, and, upon a re- 
 view, pronounced them all to be very good, 
 can see all their beauty. 
 
 Our determinations with regard to the 
 beauty of objects, may, I think, be distin- 
 guished into two kinds ; the first we may 
 call instinctive, the other rational. 
 
 Some objects strike us at once, and ap- 
 pear beautiful at first sight, without any re- 
 flection, without our being able to say why 
 we call them beautiful, or being able to spe- 
 cify any perfection which justifies our judg- 
 ment. Something of this kind there seems 
 to be in brute animals, and in children 
 before the use of reason ; nor does it end 
 with infancy, but continues through life. 
 
 In the plumage of birds and of butterflies, 
 in the colours and form of flowers, of shells, 
 and of many other objects, we perceive a 
 beauty that delights ; but cannot say what 
 it is in the object that should produce that 
 emotion. 
 
 The beauty of the object may in such 
 cases be called an occult quality. We know 
 well how it affects our senses ; but what it 
 is in itself we know not. But this, as well 
 as other occult qualities, is a proper subject 
 of philosophical disquisition ; and, by a care- 
 ful examination of the objects to which Na- 
 ture hath given this amiable quality, we 
 may perhaps discover some real excellence 
 in the object, or, at least, some valuable 
 purpose that is served by the effect which 
 it produces upon us. 
 
 This instinctive sense of beauty, in differ- 
 ent species of animals, may differ as much 
 as the external sense of taste, and in each 
 species be adapted to its manner of life. By 
 this perhaps the various tribes are led to 
 associate with their kind, to dwell among 
 certain objects rather than others, and to 
 construct their habitation in a particular 
 manner. [744] 
 
 There seem likewise to be varieties in 
 the sense of beauty in the individuals of the 
 same species, by which they are directed in 
 the choice of a mate, and in the love and 
 care of their offspring. 
 
 " We see," says Mr Addison, " that 
 every different species of sensible creatures 
 has its different notions of beauty, and that 
 each of them is most affected with the 
 beauties of its own kind. This is nowhere 
 more remarkable than in birds of the same 
 shape and proportion, where we often see 
 the mate determined in his courtship by the 
 single grain or tincture of a feather, and 
 never discovering any charms but in the 
 colour of its own species." 
 
 '< Scit thalamo servare fidcm, sanctaeque veretur 
 
 Connubii leges ; non ilium in pectore candor 
 
 SoUicitat niveus ; neque pravum accendit amo. 
 rem 
 
 [74.2-744]
 
 CHAP, v."] 
 
 OF BEAUTY. 
 
 501 
 
 Splendida lanugo, vel honesta in vertice crista ; 
 Purpureusve nitor pennarum ; ast apmiiia late 
 Fceminea explorat cautiis, maculasque requirit 
 Cognatas, paribusque iiiterlita c rpora guttis : 
 Ni I'acert't, pictis sylvam circum uiiJique 1110113- 
 
 tris 
 Confusam aspiceres vulgo, partusque biformes, 
 Et genus ambiguum, el veneris monumenta ne- 
 
 lands:. 
 
 " Hinc merula in nigrn se oblectat nigra marito; 
 Hiiic socium lasciva petit philomela canorum, 
 Agnoscitque pares soiiitus ; liinc noclua teiram 
 Canitiem alarum, et glaueos miratur ocellos. 
 Nempe sibi semper constat, crescitque quotannis 
 I.,ucida progenies, castes contcssa parentes : 
 Vere novo exultat, plumasque decora jiiventus 
 Explicat ad solem, patriisque coloribus ardet." 
 
 In the human kind there are varieties in 
 the taste of beauty, of wliich we can no 
 more assign a reason than of the variety of 
 their features, though it is easy to perceive 
 that very important ends are answered by 
 both. These varieties are most observable 
 in the judgments we form of tlie features of 
 the other sex ; and in this the intention of 
 nature is most apparent. [745] 
 
 As far as our determinations of the com- 
 parative beauty of objects are instinctive, 
 they are no subject of reasoning or of criti- 
 cism ; they are purely the gift of nature, 
 and we have no standard by which they may 
 be measured. 
 
 But there are judgments of beauty that 
 may be called rational, being grounded on 
 some agreeable quality of the object wliieh is 
 distinctly conceived, and may be specified. 
 This distinction between a rational judg- 
 ment of beauty and that which is instinc- 
 tive, may be illustrated by an instance. 
 
 In a heap of pebbles, one that is remark- 
 able for brilliancy of colour and regularity 
 of figure, will be picked out of the heap by a 
 child. He perceives a beauty in it, puts a 
 value upon it, and is fond of the property ot 
 it. For this preference, no reason can be 
 given, but that children are, by their con- 
 titution, fond of brilliant colours, and ot 
 regular figures. 
 
 Suppose again tliat an expert mechanic 
 views a well constructed machine. He sees 
 all its parts to be made of the fittest mate- 
 rials, and of the most proper form ; no- 
 thing superfluous, nothing deficient ; every 
 part adapted to its use, and the whole fitted 
 in the most perfect manner to the end for 
 which it is intended. He pronounces it to 
 be a beautiful machine. lie views it with 
 the same agreeable emotion as the child 
 viewed the pebble ; but he can give a reason 
 for his judgment, and jioint out the particu- 
 lar perfections of the object ou which it is 
 grounded. [V-ltJJ 
 
 Although the instinctive and the rational 
 sense of beauty may be perfectly distin- 
 guislied in Hp(;culation, yet, in passing jii'lg- 
 ment upon particular olijects, tiiey are ofitii 
 so mixed and confounded, that it is diificull 
 to assign to e:i<-h lis own jirovincc. Nay, it 
 [71-5 7i7] 
 
 may often happen, that a judgment of the 
 beauty of an object, wliich was at first 
 merely instinctive, shall afterwards become 
 rational, when we discover some latent per- 
 fection of which that beauty in the object ia 
 a sign. 
 
 As the sense of beauty may be distin- 
 guished into instinctive and rational ; so I 
 think beauty itself may be distinguished into 
 original and derived. 
 
 As some objects shine by their own light, 
 and many more by light that is borrowed 
 and reflected ; so I conceive the lustre of 
 beauty in some objects is inherent and 
 original, and in many others is borrowed 
 and reflected. 
 
 There is nothing more common in the 
 sentiments of all mankind, and in the lan- 
 guage of all uations, than what may be 
 called a communication of attributes ; that 
 is, transferring an attribute, from the sub- 
 ject to which it properly belongs, to some 
 related or resembling subject. 
 
 The various objects which nature pre- 
 sents to our view, even those that are most 
 ditferent in kind, have innumerable simili- 
 tudes, relations, and analogies, which we 
 contemplate with pleasure, and which lead 
 us naturally to borrow words and attributes 
 from one object to express what belongs to 
 another. The greatest part of every lan- 
 guage under heaven is made up of words 
 borrowed from one thing, and applied to 
 something supposed to have some relation 
 or analogy to their first signification. [T-ll] 
 The attributes of body we ascribe to mind, 
 and the attributes of mind to material ob- 
 jects. To inanimate things we ascribe life, 
 and even intellectual and moral qualities. 
 And, although the qualities that are thus 
 made common belong to one of the subjects 
 in the proper sense, and to the other meta- 
 phorically, these different senses are often 
 so mixed in our imagination, as to produce 
 the same sentiment with regard to both. 
 
 It is therefore natural, and agreeable to 
 the strain of human sentiments and of 
 human language, that in many cases the 
 beauty which originally and properly is in 
 the thing signified, should be transferred 
 to the sign ; that wliich is in the cause to 
 the efl'ect ; that which is in the end to the 
 means; and that which is in the agent to 
 the instrument. 
 
 If what was s.iid in the last chapter of 
 the distinction between the grandeur wliich 
 we ascribe to qualities of mind, and that 
 which we ascribe to material objects, be 
 well founiled, this distinction of the beauty 
 of oljjects will easily be admit ttd as per- 
 fectly analagous to it. 1 hhall therefore 
 iiiily iHu^>lrale it by an example. 
 
 'J'lieie is nothing in the exterior of a man 
 more lovely and more attractive than per- 
 fect good breeding. lUit what is lliiH good
 
 502 
 
 OxV THK INTELLECTUAL POWERS. 
 
 [es-say 
 
 VIII. 
 
 breeding ? It cousists of all the external 
 signs of due respect to our superiors, con- 
 descension to our inferiors, politeness to all 
 with wliom we converse or have to do, 
 joined in the fair sex with that delicacj' of 
 outward behaviour which becomes them. 
 And how comes it to have such charms in 
 the eyes of all mankind ; for this reason 
 only, as I apprehend, that it is a natural 
 sign of that temper, and those affections 
 and sentiments with regard to others, and 
 with regard to ourselves, which are in 
 themselves truly amiable and beautiful- 
 
 This is the original, of which good breed- 
 ing is the picture ; and it is the beauty of 
 the original that is reflected to our sense 
 by the picture. The beauty of good breed- 
 ing, therefore, is not originally in the ex- 
 ternal behaviour in which it consists, but is 
 derived from the qualities of mind which it 
 expresses. And though there may be good 
 breeding without the amiable qualities of 
 raind, its beauty is still derived from what 
 it naturally expresses. [748] 
 
 Having explained these distinctions of 
 our sense of beauty into instinctive and 
 rational, and of beauty itself into original 
 and derived, I would now proceed to give 
 a general view of those quahties in objects, 
 to which we may justly and rationally 
 ascribe beauty, whether original or derived. 
 
 But here some embarrassment arises 
 from the vague meanmg of the word beauty, 
 which I had occasion before to observe. 
 
 Sometimes it is extended, so as to include 
 everything that pleases a good taste, and 
 so comprehends grandeur and novelty, as 
 well as what in a more restricted sense is 
 called beauty. At other times, it is even 
 by good writers confined to the objects of 
 sight, when they are either seen, or remem- 
 bered, or imagined. Yet it is admitted by 
 all men, that there are beauties in music ; 
 that there is beauty as well as sublimity in 
 composition, both in verse and in prose ; 
 that there is beauty in characters, in affec- 
 tions, and in actions. These are not ob- 
 jects of sight ; and a man may be a good 
 judge of beauty of various kinds, who has 
 not the faculty of sight. 
 
 To give a determinate meaning to a word 
 so variously extended and restricted, I 
 know no better way than what is suggested 
 by the common division of the objects of 
 taste into novelty, grandeur, and beauty. 
 Novelty, it is plain, is no quality of the 
 new object, but merely a relation which it 
 has to the knowledge of the person to whom 
 it is new. Therefore, if this general divi- 
 sion be just, every quality in an object that 
 pleases a good taste, must, iu one degree 
 or another, have either grandeur or beauty. 
 It may still be difficult to fix the precise 
 limit betwixt grandeur and beauty 4 but 
 they must together comprehend everything 
 
 fitted by its nature to please a good taste — 
 that is, every real perfection and excellence 
 in the objects we contemplate. [749] 
 
 In a poem, in a picture, in a piece of 
 music, it is real excellence that pleases a 
 good taste. In a person, every perfection 
 of the mind, moral or intellectual, and every 
 perfection of the body, gives pleasure to the 
 spectator, as well as to the owner, when 
 there is no envy nor malignity to destroy 
 that pleasure. 
 
 It is, therefore, in the scale of perfection 
 and real excellence that we must look for 
 what is either grand or beautiful in objects. 
 What is the proper object of admiration is 
 grand, and what is the proper object of love 
 and esteem is beautiful. 
 
 This, I think, is the only notion of beauty 
 that corresponds with the division of the 
 objects of taste which has been generally 
 received by philosophers. And this con- 
 nection of beauty with real perfection, was 
 a capital doctrine of the Socratic school. 
 It is often ascribed to Socrates, in the dia- 
 logues of Plato and of Xenophon. 
 
 We may, therefore, take a view, first, of 
 those qualities of mind to which we may 
 justly and rationally ascribe beauty, and 
 then of the beauty we perceive in the objects 
 of sense. We shall find, if I mistake not, 
 that, in the first, original beauty is to be 
 found, and that the beauties of the second 
 class are derived from some relation they 
 bear to mind, as the signs or expressions 
 of some amiable mental quality, or as the 
 effects of design, art, and wise contrivance. 
 
 As grandeur naturally produces admira- 
 tion, beauty naturally produces love. We 
 may, therefore, justly asci-ibe beauty to those 
 qualities which are the natural objects of 
 love and kind affection. 
 
 Of this kind chiefly are some of the moral 
 virtues, which, in a peculiar manner, con- 
 stitute a lovely character. Innocence, gen- 
 tleness, condescension, humanity, natural 
 affection, public spirit, and the whole train 
 of the soft and gentle virtues: these qualities 
 are amiable from their very nature, and on 
 account of their intrinsic worth. [750] 
 
 There are other virtues that raise admira- 
 tion, and are, therefore, grand ; such as 
 magnanimity, fortitude, self-command, su- 
 periority to pain and labour, superiority to 
 pleasure, and to the smiles of Fortune as 
 well as to her frowns. 
 
 These awful virtues constitute what is 
 most grand in the human character ; the 
 gentle virtues, what is most beautiful and 
 lovely. As they are virtues, they draw the 
 approbation of our moral faculty ; as they 
 are becoming and amiable, they affect our 
 sense of beauty. 
 
 Next to the amiable moral virtues, there 
 are many intellectual talents which have an 
 intrinsic value, and draw our loveanc' esteem 
 
 f7 4S-750]
 
 Cli.AP. IV.J 
 
 OF BEAUTY. 
 
 503 
 
 to those who possess them. Such are, 
 knowledge, good sense, wit, humour, clieer- 
 fulness, g.iod taste, excellence in any of the 
 fine arts, in eloquence, in dramatic action; 
 and, we may add, excellence in every art of 
 peace or war that is useful in society. 
 
 There are likewise talents which we refer 
 to the body, which have an original beauty 
 and comeliness ; such as healtli, strength, 
 and agility, the usual attendants of youth ; 
 skill in bodily exercises, and skill in the 
 mechanic arts. These are real perfections 
 of the mail, as they increase his power, and 
 render the body a fit instrument for the 
 mind. 
 
 I apprehend, therefore, that it is in the 
 moral and intellectual perfections of mind, 
 and in its active powers, that beauty origin- 
 ally dwells ; and that from this as the foun- 
 tain, all the beauty which we perceive in 
 the visible world is derived. [751] 
 
 Tliis, I think, was the opinion of the 
 
 ancient philosophers before-named ; and it 
 
 has been adopted by Lord Shaftesbury and 
 
 Dr Ake.'iside among the modenis. 
 
 "Mind, mind alone, bear witness, earfh an;I heav'n I 
 The living fountains in itselt contains 
 Ofbeauteoiis and sublime. Here hand in hatid 
 Si paranuiunt the graces. Here enthron'd, 
 Celestial Venus, with divinost airs, 
 Invites the soul to never-t'adingjoy." — Akenside. 
 
 But neither mind, nor any of its qualities 
 or ]x)wers, is an immediate object of per- 
 ception to man. We are, indeed, imme- 
 diately conscious of the operations of our 
 own mind ; and every degree of ])erfection 
 in tliem gives the purest pleasure, with a 
 proportional degree of self-esteem, so flat- 
 tering to self-love, that the great difficulty 
 is to keep it within just bounds, so that we 
 may not think of ourselves above what we 
 ought to thinlc. 
 
 Other minds we perceive only through 
 the medium of matei'ial objects, on which 
 their signatures are impressed. It is 
 through this medium that we perceive life, 
 activity, wisdom, and every moral and in- 
 tellectual quality in other beings. The 
 signs of those qualities are immediately 
 perceived by the senses ; by them the ipia- 
 lities themselves are reflected to our under- 
 standing ; and we are very apt to attribute 
 to the sign the beauty or the grandeur 
 which is properly and originally in tlie 
 thini;s signified. 
 
 The invisible Creator, the Fountain of 
 all f)erfection, hath stamped upon all his 
 works signatures of his divine wisdom, 
 power, and benignity, which are visible to 
 all men. The works of men in .science, in 
 the arts of taste, and in the mechanical 
 arts, bear the signatures of those qualities 
 ol'mind which were emplitycil in theii' jjrn- 
 diiction. Their external behaviour and 
 conduct in life expresses tlie good or bad 
 qualities of their mind. | V-''- 1 
 [7/;i-7.i.3] 
 
 In every species of animals, we perceive 
 by visible signs their instincts, their appe- 
 tites, their aftections, their sagacity. Even 
 in the inanimate world, there are many 
 things analogous to the qualities of mind ; 
 so that there is hardly anything belonging 
 to mind whicli may not be represented by 
 images taken from the objects of sense ; 
 and, on the other hand, every object of 
 sense is beautified, by borrowing attire from 
 the attributes of mind. 
 
 Thu=, the beauties of mind, though invi- 
 sible in themselves, are perceived in the 
 objects of sense, on which their image is 
 impressed. 
 
 If we consider, on the otlier hand, the 
 qualities in sensible objects to which we 
 ascribe beauty, I apprehend we shall find 
 in all of them some relation to mind, and 
 the greatest in those that are most beau- 
 tiful. 
 
 When we consider inanimate matter 
 abstractly, as a substance endowed with 
 the qualities of extension, solidity, divisi- 
 bility, and mobility, there seems to be 
 nothing in these qualities that affects our 
 sense of beauty. But when we contem- 
 plate the globe which we inhabit, as fitted 
 by its form, by its motions, and by its fur- 
 niture, for the habitation and support of an 
 infinity of various orders of living creatures, 
 from the lowest reptile up to man, we have 
 a glorious spectacle indeed ! with which 
 the grandest and the most beautiful struc- 
 tures of human art can bear no compa- 
 rison. 
 
 The only perfection of dead matter is its 
 being, by its various forms and qualities, 
 .so admirably fitted for the purposes of ani- 
 mal life, and chiefly that of man. It fur- 
 nishes the materials of every art that tends 
 to the support or the embellishment of 
 human life. By the Supreme Artist, it is 
 organized in the various tribes of the veget- 
 able kingdom, and endowed with a kind of 
 life ; a wurk whicli human art cannot imi- 
 tate, nor human understanding compre- 
 hend, [irui] 
 
 In the bodies and various organs of the 
 animal tril)es, there is a composition of 
 matter still more wonderful and more mys- 
 terious, though we see it to bo admirably 
 adai)ted to the purposes and manner of lifo 
 of every species. But in <very form, unor- 
 ganized, vegetable, or animal, it derives its 
 beauty from the jiurjioses to whicli it is 
 subservient, or from the signs of wisdom 
 or of other mental qualities which it ex- 
 hibits. 
 
 The qualities of inanimate matter, in 
 which wo perceive beauty, are — sound, 
 colour, form, and motion ; tlie first an ob- 
 ject of hearing, the oilier three of sight; 
 which we may consitler in onli'r. 
 
 ill a single note, Houmlt il by a very iiiie
 
 501 
 
 ON THE INTELLECTUAL POWERS. 
 
 [kssay 
 
 VIII. 
 
 voice, there is a beauty which we do not 
 perceive in the same note, sounded by a bad 
 voice or an imperfect instrument. I need 
 not attempt to enumerate the perfections 
 in a single note, which give beauty to it. 
 Some of them have names in the science of 
 music, and there perhaps are others which 
 have uo names. But I think it will be 
 allowed, that every quality which gives 
 beauty to a single note, is a sign of some 
 perfection, either in the organ, whether it 
 be the human voice or an instrument, or in 
 the execution. The beauty of the sound 
 is both the sign and the effect of this per- 
 fection ; and the perfection of the cause is 
 the only reason we can assign for the beauty 
 of the effect. 
 
 In a composition of sounds, or a piece of 
 music, the beauty is either in the harmony, 
 the melody, or the expression. The beauty 
 of expression must be derived, either from 
 the beauty of the thing expressed, or from 
 the art and skill employed in expressing it 
 properly. 
 
 In harmony, the very names of concord 
 and discord are metaphorical, and suppose 
 some analogy between the relations of sound, 
 to which they are figuratively applied, and 
 the relations of minds and affections, which 
 they originally and properly signify. [754] 
 
 As far as I can judge by my ear, when 
 two or more persons, of a good voice and 
 ear, converse together in amity and friend- 
 ship, the tones of their difl'erent voices are 
 concordant, but become discordant when 
 they give vent to angry passions ; so that, 
 without hearing what is said, one may know 
 by the tones of the different voices, whether 
 they quarrel or converse amicably. This, 
 indeed, is not so easily perceived in those 
 who have been taught, by good-breeding, 
 to suppress angry tones of voice, even when 
 they are angry, as in the lowest rank, who 
 express their angry passions without any 
 restraint. 
 
 When discord arises occasionally in con- 
 versation, but soon terminates in perfect 
 amity, we receive more pleasure than fr()m 
 pei'fect unanimity. In like manner, in the 
 harmony of music, discordant sounds are 
 occasionally introduced, but it is always in 
 01 der to give a relish to the most perfect 
 concord that follows. 
 
 Whether these analogies, between the 
 harmony of a piece of music, and harmony 
 ill the intercourse of minds, be merely fanci- 
 ful, or have any real foundation in fact, I 
 submit to those who have a nicer ear, and 
 have applied it to observations of this kind. 
 If they have any just foundation, as they 
 seem to me to have, they serve to account 
 for the metaphorical application of the 
 names of concord and discord to the rela- 
 tions of sounds ; to account for the pleasure 
 we have from harmony in music ; and to 
 
 shew, that the beauty of harmony is derived 
 from the relation it has to agreeable afiec- 
 tions of mind. 
 
 With regard to melody. J leave it to the 
 adepts in the science of music, to determine 
 whether music, composed according to the 
 established rules of harmony and melody, 
 can be altogether void of expression ; and 
 whether music that has no expression can 
 have any beauty. To me it seems, that 
 every strain in melody that is agreeable, is 
 an imitation of the tones of the human 
 voice in the expression of some sentiment 
 or passion, or an imitation of some other ob- 
 ject in nature ; and that music, as well as 
 poetry, is an imitative art. [755] 
 
 The sense of beauty in the colours, and 
 in the motions of inanimate objects, is, I 
 believe, in some cases instinctive. We see 
 that children and savages are pleased with 
 brilliant colours and sprightly motions. In 
 persons of an improved and rational taste, 
 there are many sources from which colours 
 and motions may derive their beauty. They, 
 as well as the forms of objects, admit of 
 regularity and variety. The motions pro- 
 duced by machinery, indicate the perfection 
 or imperfection of the mechanism, and may 
 be better or worse adapted to their end, and 
 from that derive their beauty or deformity. 
 
 The colours of natural objects, are com- 
 monly signs of some good or bad quality iii 
 the object ; or they may suggest to the 
 imagination something agreeable or dis- 
 agreeable. 
 
 In dress and furniture, fashion has a con- 
 siderable influence on the preference we give 
 to one colour above another. 
 
 A number of clouds of diff'erent and ever- 
 changing hue, seen on the ground of a serene 
 azure sky, at the going down of the sun, 
 present to the eye of every man a glorious 
 spectacle. It is- hard to say, whether we 
 should call it grand or beautiful. It is both 
 in a high degree. Clouds towering above 
 clouds, variously tinged, according as they 
 approach nearer to the direct rays of the 
 sun, enlarge our conceptions of the regions 
 above us. They give us a view of the fur- 
 niture of those regions, which, in an un- 
 clouded air, seem to be a perfect void ; but 
 are now seen to contain the stores of wind 
 and rain, bound up for the present, but to 
 be poured down upon the earth in due sea- 
 son. Even the simple rustic does not look 
 upon this beautiful sky, merely as a show 
 to please the eye, but as a happy omen of 
 fine weather to come. 
 
 The proper arrangement of colour, and of 
 light and shade, is one of the chief beauties 
 of painting ; but this beauty is greatest, 
 when that arrangement gives the most dis- 
 tinct, the most natural, and the most agree- 
 able image of that which the painter uiteud- 
 ed to represent. [756] 
 
 [754-756"]
 
 CHAP. IV.] 
 
 OF BEAUTY. 
 
 505 
 
 If we consider, in the last place, the 
 beauty of form or figure in inanimate ob- 
 jects, this, according to Dr Hutcheson, re- 
 sults from regularity, mixed with variety. 
 Here, it ought to be observed, that regu- 
 larity, in all cases, expresses design and 
 art : for nothing regular was ever the work 
 
 O O .... 
 
 of chance ; and where regularity is jomed 
 with variety, it expresses design more 
 strongly. Besides, it has been justly ob- 
 served, that regular figures are more easily 
 and more perfectly comprehended by the 
 mind than the irregular, of which we can 
 never form an adequate conception. 
 
 Although straight lines and plain surfaces 
 have a beauty from their regularity, they 
 admit of no variety, and, tlierefore, are 
 beauties of the lowest order. Curve lines 
 and surfaces admit of infinite variety, joined 
 with every degree of regularity ; and, there- 
 fore, in many cases, excel in beauty those 
 that are etraight. 
 
 But the beauty arising from regularity 
 and variety, must always yield to that which 
 ari.-es from the fitness of the form for the 
 end intended. In everything made for an 
 end, the form must be adapted to that end ; 
 and everything in the form that suits the 
 end, is a beauty ; everything that uiifits it 
 for its end, is a deformity. 
 
 The forms of a pillar, of a sword, and of 
 a balance are very different. Eacli may 
 have great beauty ; but tliat beauty is de- 
 rived from the fitness of the form and of 
 the matter for the purpose intended. [757] 
 
 Were we to consider the form of the earth 
 itself, and the various furniture it contains, 
 of the inanimate kind ; its distribution into 
 land and sea, mountains and valleys, rivers 
 and springs of water, the variety of soils 
 that cover its surface, and of mineral and 
 metallic substances laid up within it, the air 
 that surrounds it, the vicissitudes of day 
 and night, and of the seasons ; the beauty 
 of all these, which indeed is superlative, 
 consists in this, that they bear the most 
 lively and striking impression of the wisdom 
 and goodness of their Author, in contriving 
 tiiem so admirably for the use of man, and 
 of their other inhabitants. 
 
 The beauties of the vegetable kingdom 
 are far superior to those of inanimate mat- 
 ter, in any form which human art can give 
 it. Hence, in all ages, men have Ijeen fond 
 to adorn their persons and their habitations 
 with the vegetable productions of nature. 
 
 The beauties of the field, of the forest, 
 and of the flower-garden, strike a child long 
 before he can reason. He is delighted with 
 what he sees ; but he knows not why- This 
 is instinct, but it is not confined to child- 
 hood ; it continues through all the stages of 
 life. It leads the florist, the Ijotanist, the 
 philosophcsr, to examine and compare the 
 ol)ject8 which Nature, by this powerful in- 
 [7.57, 7.'>h] 
 
 stinct, recommends to his attention. By 
 degrees, he becomes a critic in beauties of 
 this kind, and can give a reason why he 
 prefers one to another. In every species, 
 he sees the greatest beauty in the plants or 
 flowers that are most perfect in their kind — 
 which have neither suttered from unkindly 
 soil nor inclement weather ; which have not 
 been robbed of their nourishment by other 
 plants, nor hurt by any accident. When he 
 examines the internal structure of those 
 productions of Nature, and traces them 
 from their embryo state in the seed to their 
 maturity, he sees a thousand beautiful con- 
 trivances of Nature, which feast his under- 
 standing more than their external form 
 delighted his eye. 
 
 Thus, every beauty in the vegetable 
 creation, of which lie has formed any ra- 
 tional judgment, expresses some perfection 
 in the object, or some wise contrivance in 
 its Author. [75S] 
 
 In the animal kingdom, we perceive still 
 greater beauties than in the vegetable- Here 
 we observe life, and sense, and activity, 
 various instincts and aftections, and, in 
 many cases, great sagacity. These are 
 attributes of mind, and have an original 
 beauty. 
 
 As we allow to brute animals a thinking 
 principle or mind, though far inferior to 
 that which is in man ; and as, in many of 
 their intellectual and active powers, they 
 very much resemble the human species, 
 their actions, their motions, and even their 
 looks, derive a beauty from the powers of 
 thought which they express. 
 
 There is a wonderful variety in their 
 manner of life ; and we find the powers they 
 possess, their outward form, and their in- 
 ward structure, exactly adapted to it. In 
 every species, the more perfectly any indi- 
 vidual is fitted for its end and manner of 
 life, the greater is its beauty. 
 
 In a race-horse, everything that expresses 
 agility, ardour, and emulation, gives beauty 
 to the animal. In a pointer, acuteness of 
 scent, eagerness on the game, and tractablc- 
 ness, are the beauties of the species. A 
 sheep derives its l)eauty from the fineness 
 and fjuantity of its fleece ; and in the wibl 
 animals, every beauty is a sign of their 
 perfection in their kind. 
 
 It is an observation of the celebrated 
 Linnieus, that, in the vegetable kingdom, 
 the poisonous plants I ave connnonlv a hirid 
 and disagreeable appearance to the eye, of 
 which he gives many instances. 1 ii|'pre- 
 hend the observation may be extended to 
 the animal kingdom, in which we commonly 
 see Homethiiig shocking to the eye in tho 
 noxious anil ])oisonons animals. 
 
 The beauties whieli anatomists and ])liy- 
 siologists describe in the internal struct nro 
 of the various (ril)os of animals; in tii«
 
 506 
 
 ON TFIE INTELLECTUAL POWERS. [essay viii. 
 
 organs of sense, of nutrition, and of motion, 
 are expressive of wise design and contriv- 
 ance, in fitting tlieni for the various kinds 
 of life for which they are intended. [759] 
 
 Thus, I think, it appears that the beauty 
 which we perceive in the inferior animals, 
 is expressive, either of such perfections as 
 their several natures may receive, or ex- 
 pressive of wise design in Him who made 
 them, and that their beauty is derived from 
 the perfections which it expresses. 
 
 But of all the objects of sense, the most 
 striking and attractive beauty is perceived 
 in the human species, and particularly in 
 the ftiir sex. 
 
 Milton represents Satan himself, in sur- 
 veying the furniture of this globe, as struck 
 with the beauty of the first happy pair. 
 
 " Two of far nobler shape, erect and tall, 
 Godlike erect! with native honour clad 
 In naken m.ijesty, seem'd lords of all. 
 And worthy seem'd, for in th ir looks divine. 
 The image of their glorious Maker, shone 
 Truth, wisdom, sanctitude severe and pure; 
 Severe, but in tiue lilial freedom plac'd. 
 Whence true authority in man ; thou(;h both 
 Not equal, as their s:x not equal seem'd. 
 For contemplation he, and valour (orni'd. 
 Forsottness she, and sweet attractive gr„ce." 
 
 In this well-known passage of Milton, 
 we see that this great poet derives the 
 beauty of the first pair in Paradise from 
 those expressions of moral and intellectual 
 qualities which appeared in their outward 
 form and demeanour. 
 
 The most minute and systematical ac- 
 count of beauty in the human species, and 
 particularly in the fair sex, I have met 
 with, is in " Crito ; or, a Dialogue on 
 Beauty," said to be written by the author 
 of " Polymetis,"* and republished by Dods- 
 ley in his collection of fugitive pieces. 
 [760] 
 
 I shall borrow from that author some 
 observations, which, I think, tend to shew- 
 that the beauty of the human body is 
 derived from the signs it exhibits of some 
 perfection of the mind or person. 
 
 All that can be called beauty in the 
 human species may be reduced to these 
 four heads : colour, form, expression, and 
 grace. The two former may be called the 
 body, the two latter the soul of beauty. 
 
 The beauty of colour is not owing solely 
 to the natural liveliness of tiesh-colour and 
 red, nor to the much greater charms they 
 receive from being properlj' blended toge- 
 ther ; but is also owing, in some degree, to 
 the idea they carry with them of good 
 health, without which all beauty grows 
 languid and less engaging, and with which 
 it always recovers an additional strength 
 a:-.d lustre. This is supported by the autho- 
 rity of Cicero. Venuntas el pukhriindo 
 corporis secend rion pute.^l a vnletud ne. 
 
 * .Spence, under the name of Sir Harry I'eau- 
 mont — H. 
 
 Here I observe, that, as the colour of the 
 body is very different in different climates, 
 every nation preferring the colour of its 
 climate, and as, among us, one man prefers 
 a fair beauty, another a brunette, without- 
 being able to give any reason for this pre- 
 ference ; this diversity of taste has no stand- 
 ard in the common principles of human 
 nature, but must arise from something that 
 is different in different nations, audnn dif- 
 ferent individuals of the same nation. 
 
 I observed before, that fashion, habit, 
 associations, and perhaps some peculiarity 
 of constitution, may have great influence 
 upon this internal sense, as well as upon 
 the external. Setting aside the judgments 
 arising from such causes, there seems to 
 remain nothing that, according to the com- 
 mon judgment of mankind, can be called 
 beauty in the colour of the species, but 
 what expresses perfect health and Hveli- 
 ness, and in the fair sex softness and deli- 
 cacy ; and nothing that can be called deform- 
 ity but what indicates disease and decline. 
 And if this be so, it follows, that the beauty 
 of colour is derived from tiie perfections 
 which it expresses. This, however, of all 
 the ingredients of beauty, is the least. [761 ] 
 The next in order is form, or proportion 
 of parts. The most beautiful form, as the 
 author thinks, is that which indicates deli- 
 cacy and softness in the fair sex, and in the 
 male either strength or agility. The beau- 
 ty of form, therefore, lies all in expression. 
 The third ingredient, which lias more 
 power than either colour or form, he calls 
 expression, and observes, that it is only the 
 expression of the tender and kind passions 
 that gives beauty ; that all the cruel and 
 unkind ones add to deformity ; and that, on 
 this account, good nature may very justly 
 be said to be the best feature, even in the 
 finest face. Modesty, sensibility, and 
 sweetness, blended together, so as either 
 to enliven or to correct each other, give al- 
 most as much attraction as the pa.ssions are 
 capable of adding to a very pretty face. 
 
 It is owing, says the author, to the great 
 force of pleasingness which attends all the 
 kinder passions, that lovers not only seem, 
 but really are, more beautiful to each other 
 than they are to the rest of the world ; be- 
 cause, when they are together, the most pleas- 
 ing passioiis are more frequently exerted in 
 each of their faces than they are in either 
 before the re.st of the world. There is then, 
 as a French author veiy well expresses it, 
 a soul upon their countenances, which does 
 not aj.pear when they are absent from one 
 another, or even in company that lays a re- 
 straint upon their features. 
 
 Thene is a great difference in the same 
 face, according as the person is in a better 
 or a worse humour, or more or less lively. 
 The best complexion, the finest features, 
 
 [759-761]
 
 CHAP. 
 
 IV.J 
 
 OF BEAUTY. 
 
 5!»7 
 
 and tlie exactest sliape, without auythinp; 
 of the miTid expressed in the face, is insipid 
 and unmoving. The finest eyes in the 
 world, with an excess of malice or rage in 
 them, will grow shocking. The passions 
 can give beauty without the assistance of 
 colour or form, and take it away where 
 these have united most strongly to give it ; 
 and therefore this part of beauty is greatly 
 superior to the other two. [762] 
 
 The last and noblest part of beauty is 
 grace, which the author thinks undefin- 
 able. 
 
 Nothing causes love so generally and ir^ 
 rcsistibly as grace. Therefore, in the m^'- 
 thology of the Greeks and Romans, the 
 Graces were the constant attendants of 
 Venus the goddess of love. Grace is lilie 
 the cestus of the same goddess, which was 
 supposed to comprehend everything that 
 was winning and engaging, and to create 
 love by a secret and inexplicable force, like 
 that of some magical charm. 
 
 There are two kinds of grace — the majes- 
 tic and the familiar ; the first more com- 
 manding, the last more deliglitful and en- 
 gaging. The Grecian painters and sculp- 
 tors used to express the former most strongly 
 in the looks and attitudes of their ]\Iiner- 
 vas, and the latter in those of Venus. This 
 distinction is marked in the description of 
 the personages of Virtue and Pleasure in 
 the ancient fable of the Choice of Hercules. 
 
 " Graceful, bui e^ch with different grace they move. 
 This striking sacred awe, that softer winning lovt." 
 
 In the persons of Adam and Eve in Pa- 
 radise, Milton has made the same distinc- 
 tion — 
 
 " Tor contemplation he, and valour formed, 
 
 For softness she, and sweet attractive griice."[76.'i] 
 
 Though grace be so difficult to be defined, 
 there are two things that hold universally 
 with relation to it. First, There is no 
 grace without motion ; some genteel or 
 pleasing motion, either of the whole liody 
 or of some limb, or at least some feature. 
 Hence, in the face, grace appears only on 
 those features that are niovaUe, and cliaiigo 
 with the various emotions and sentiments 
 of the mind, such as tlie eyes and eye- 
 brows, the mouth and parts adjacent. 
 When Venus appeared to her son ^neas 
 in disguise, and, after some conversation 
 with liim, retired, it was liy the grace of 
 her motion in retiring that he discovered 
 her lie to truly a goddess. 
 
 " Dixit, et avcrtcns rosea cervice refulsit, 
 Ambrosltcque comjE divinnm vertice odon m 
 .S|)iravere; pedes vestis defluxit ad imos; 
 Kt vera inccssu patuit dea. Hie, ubi matrcni 
 Agnovit," &e. 
 
 A srcnd oliscrvation is. That tlieie can 
 I e no grace with \\\\\\u>\>r\vXy , or that no- 
 thing can be graceful tliat is not adapted to 
 the character and situation of the person. 
 
 From thcHo olieervations, whicli a[)pear 
 
 to me to be just, we may, I think, conclude, 
 that grace, as far asit is vtsilile, consists of 
 those motions, either of the whole body, or 
 of a part or feature, which express the most 
 perfect propriety of conduct and sentiment 
 in an amiable character. 
 
 Those motions must be different in dif- 
 ferent characters ; they nmst vary with 
 every variation of emotion and sentiment ; 
 they may express either dignity or respect, 
 confidence or reserve, love or just resent- 
 ment, esteem or indignation, zeal or indif- 
 ference. Every passion, sentiment, or emo- 
 tion, that in its nature and degree is just 
 and proper, and corresponds perfectly with 
 the character of the person, and with the oc- 
 casion, is what may we call the soul of grace. 
 The I ody or visible part consists of those 
 emotions and features which give the true 
 and unaffected expression of this soul. [764] 
 
 Thus, I think, all the ingredients of 
 human beauty, as they are enumerated and 
 described by this ingenious author, termi- 
 nate in expression : they either express 
 some perfection of the body, as a part of the 
 man, and an instrument of the mind, or 
 some amiaiile quality or attribute of the 
 mind itself. 
 
 It cannot, indeed, lie denied, that the 
 expression of a fine countenance may be 
 unnaturally disjoined from the amiaide qua- 
 lities which it naturally expresses : Imt we 
 presume the contrary till we have clear evi- 
 dence ; and even then we pay homage to 
 the expression, as we do to the throne when 
 it happens to be unworthily filled. 
 
 Whether what I have offered to shew, 
 that all the beauty of the objects of sense 
 is borrowed, and derived from the beauties 
 of mind which it expresses or suggests to 
 the imagination, be well-founded or not, I 
 hope this terrestrial Venus will not be 
 deemed less worthy of the homage which 
 has always been paid to her, by being con- 
 ceived more nearly allied to the celestial 
 than she has commonly been represented. 
 
 To make an end of this subject, taste 
 seems to be progressive as man is. Child- 
 ren, when refreshed by sleep, and at ease 
 from pain and hunger, are disposed to at- 
 tend to the objects about them ; they are 
 pleased with brilliant colours, gaudy orna- 
 ments, regular forms, cheerful counte- 
 nances, noisy mirth an<l glee. Such is 
 the taste of childhood, whicli we must con- 
 clude to be given for wise purposes. A 
 great part of the happiness of tliat period 
 of life is derived from it ; and, therefore, it 
 ought to be indulged. It leads tbeni to 
 attend to objects wbieli they may afterwards 
 find worthy of tbeir alti'Utiou. It puts tliein 
 upon exerting tlieir infant faculties (tf body 
 and mind, which, by such exertions, aro 
 daily strengthened and improved. [76''>1 
 
 As tli<7 advance in years and in under
 
 508 
 
 ON THE INTELLECTUAL POWERS. [essay viii. 
 
 Btanding, other beauties attract their atten- 
 tion, which, by their novelty or superiority, 
 throw a siiade upon those they formerly ad- 
 mired. They delight in feats of agility, 
 strength, and art ; they love those that ex- 
 cel in them, and strive to equal them. In 
 the tales and fables they hear, they begin to 
 discern beauties of mind. Some characters 
 and actions appear lovely, others give dis- 
 gust. The intellectual and moral powers 
 begin to open, and, if cherished by favour- 
 able circumstances, advance gradually in 
 strength, till they arrive at that degree 
 of perfection to which human nature, in its 
 present state, is limited. 
 
 In our progress from infancy to maturity, 
 our faculties open in a regular order ap- 
 pointed by Nature ; the meanest first, those 
 of more dignity in succession, until the mo- 
 ral and rational powers finish the man. 
 Every faculty furnishes new notions, brings 
 new beauties into view, and enlarges the 
 province of taste; so that we may say, 
 there is a taste of childhood, a taste of 
 youth, and a manly taste. Each is beau- 
 tiful in its season ; but not so much so, 
 when carried beyond its season. Not that 
 the man ought to dislike the things that 
 please the child or the youth, but to put 
 less value upon them, compared with other 
 beauties, with which he ought to be ac- 
 quainted. 
 
 Our moral and rational powers justly 
 claim dominion over the whole man. Even 
 taste is not exempted from their authority ; 
 it must be subject to that authority in 
 every case wherein we pretend to reason or 
 dispute about matters of taste ; it is the voice 
 of reason that our love or our admiration 
 
 ought to be proportioned to the merit of the 
 object. When it is not grounded on real 
 worth, it must be the effect of constitution, 
 or of some habit, or casual association. A 
 fond mother may see a beauty in her dar- 
 ling child, or a fond author in his work, to 
 which the rest of the world are blind. In 
 such cases, the affection is pre-engaged, 
 and, as it were, bribes the judgmeut, to 
 make the object worthy of that affection. 
 For the mind cannot be easy in putting a 
 value upon an object beyond what it con- 
 ceives to be due. When affection is not 
 carried away by somgL-natural or acquired 
 bias, it naturally is and ought to be led by 
 the judgment. [766] 
 
 As, in the division which I have followed 
 of our intellectual powers, I mentioned 
 Moral Perception and Consciousness, the 
 reader ^may expect that some reason should 
 be given, why they are not treated of in 
 this place. 
 
 As to Consciousness, what I think neces- 
 sary to be said upon it has been already 
 said. Essay vi., chap. 5. As to the faculty 
 of moral perception, it is indeed a most im- 
 portant part of human understanding, and 
 well worthy of the most attentive considera- 
 tion, since without it we could have no con- 
 ception of right and wrong, of duty and 
 moral obligation, and since the first princi- 
 ples of morals, upon which all moral rea- 
 soning must be grounded, are its immediate 
 dictates ; but, as it is an active as well as 
 an intellectual power, and has an immediate 
 relation to the other active powers of the 
 mind, I apprehend that it is proper to defer 
 the consideration of it till these be explained. 
 
 [766]
 
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