f i (QorncU Utttucraity Ilthrary Jltlfara. Nfiu f Drfe BOUGHT WITH THE INCOME OF THE SAGE ENDOWMENT FUND THE GIFT OF HENRY W. SAGE 1891 j^I 2[5 ibo: Gr r ■T ]/f^ MV/^/^/ I 4 1.*5k PEB 1 4 1949 J ^"^ 1 l,Q5r5! ■" ||fcCul^^*iO?^ ■3CT 4 /^ ■■■^f./.^ i The original of tliis book is in tine Cornell University Library. There are no known copyright restrictions in the United States on the use of the text. http://www.archive.org/details/cu31924092291065 IMMANUEL KANTS CRITIQUE OF PURE REASON |n €^0mm«raoratron oi tijj €mimux^ rrf its TRANSLATED INTO ENGLI8S F. MAX MtJLLER WITH AN HISTOEICAL INTRODUCTION BY LUDWIG NOIRfi MACMILLAN AND CO. 1881 [ All rights reserved ] A. ^ yvf. CORNE university! k:. library IMMANUEL KANT'S CRITIQUE OF PURE REASON iirst fart CONTAINING- 1. PREFACE BY P. MAX MtJLLER 2. HISTORICAL INTRODUCTION BY LUDWIG NOIRfi 3. SUPPLEMENTS OF THE SECOND EDITION OF THE CRITIQUE MACMILLAN AND CO. 1881 [All rights reserved ] OXFORD: PRINTED BY E. PIOKAED HALL, M.A., AND J. H. STACY. PKINTEES TO THE UNIVEESITT. TABLE OF CONTENTS. PAGE i-lxii. Translator's Preface L. Noibe's Historical Introduction 1-360 Introduction . . i Ancient Philosophy . 8 Mediceval Philosophy . . -67 Modern Philosophy . . . ... 11 3 Descartes . ... 113 The Materialistic Tendency . . . .1.58 Gassendi. Hobbes . . -158 The Idealistic Tendency . ..171 Geulinx. Malebranche. Berkeley . 171 The Monistic Tendency 187 Spinoza . . . . . . 187 The Empirical Tendency . . 229 Locke ... . . 229 The Individualistic Tendency . . . -265 Leibniz ...... 265 I. The theory of intellectual perception . .283 II. Physics . . ..... 299 III. Metaphysics . . . . . .313 The Skepsis ......... 329 Hume. ......... 329 VOL. I. a 3 TABLE OF CONTENTS. Peincipal Additions made by Kant in the Second Edition OF THE CeITIQTJE OF PUEE REASON . Supplement 1 . . Supplement II. Preface to Second Edition . Supplement III. Table of Contents of Second Edition Supplement IV. ....... Introduction I. Of the difference between pure and em- pirical knowledge II. We are in possession of certain cognitions a priori, and even the ordinary understanding is never without them . ... Supplement V. . .... Supplement VI. . ...... V. In all theoretical sciences of reason synthetical judg ments a priori are contained as principles VI. The general problem of pure reason . Supplement VII. . . , . Supplement VIII. . . . Transcendental exposition of the concept of space Supplement IX. ...... Supplement X. ...... . Transcendental exposition of the concept of time Supplement XI. . . Supplement XII. Supplement XIII. . . Supplement XIV. . . Deduction of the pure concepts of the understanding . Of the possibility of connecting in general . Of the original synthetical unity of apperception The principle of the synthetical unity of apperception i the highest principle of all employment of the under 361 .363 364 391 398 398 400 403 405 405 408 413 414 414 416 417 417 418 424 430 432 432 432 434 standing 437 TABLE OF CONTENTS. PARE What is the objective unity of self-consciousness 1 . . 440 The logical form of all judgments consists in the objective unity of apperception of the concepts contained therein . 441 All sensuous intuitions are subject to the categories as conditions under which alone their manifold contents can come together in one consciousness . . . .442 The category admits of no other employment for the cognition of things but its application to objects of experience ... .... 445 Of the application of the categories to objects of the senses in general ...... ' . . 448 Transcendental deduction of the universally possible em- ployment of the pure concepts of the understanding in experience ......... 455 Results of this deduction of the concepts of the under- standing . . .... . 460 Comprehensive view of this deduction .... 462 Supplement XV. ... . 463 Supplement XVI a. ........ 464 I. Axioms of Intuition .... . . 464 Supplement XVI b 465 II. Anticipations of Perception . ... 465 Supplement XVII 467 III. Analogies of Experience . . . . -467 Supplement XVIII. ... . . 469 A. First Analogy. Principle of the permanence of sub- stance .... .... 469 Supplement XIX 47 1 B. Second Analogy. Principle of the succession of time, according to the law of causality . . • -471 Supplement XX 473 C. Third Analogy. Principle of co-existence according to the law of reciprocity or community . . -473 TABLE OF CONTENTS. PAGE )Supplement XXI. • • • • •475 Refutation of Idealism . • • • -475 Theorem. The simple but empirically determined con- sciousness of my own existence proves the existence of objects in space outside myself . • • •47" Supplement XXII. . . • • 480 General note on the system of the principles . . 480 Supplement XXIII. . .... 486 Supplement XXIV. . • 4^7 Supplement XSV. . ... .49° Supplement XXVI. . 49' Supplement XXVII. . . . . 492 Refutation of Mendelsohn's proof of the permanence of the soul ... . . 497 Conclusion of the solution of the psychological paralogism . 506 General note on the transition from rational psychology to cosmology . ....... 507 Supplement XXVIII. . ..... 511 TEANSLATOR'S PREFACE. Why I thought I might translate Kant's Critique. ' But how can you waste your time on a translation of Kant's Critik der reinen VernunftT This question, whicli has been addressed to me by several friends, I think I shall best be able to answer in a preface to that translation itself. And I shall try to answer it point by point. First, then, with regard to myself. Why should I waste my time on a translation of Kant's Critik der reinen Yernunft ? — that is, Were there not other per- sons more fitted for that task, or more specially called upon to undertake it ? It would be the height of presumption on my part to imagine that there were not many scholars who could have performed such a task as well as myself, or far better. All I can say is, that for nearly thirty years I have been waiting for some one really quah- fied, who would be willing to execute such a task, and have waited in vain. What I feel convinced of is that an adequate translation of Kant must be the work of a German scholar. That conviction was deeply impressed on my mind when reading, now many years ago, Kant's great work with a small class of young students at Oxford — among whom I may mention the names of Appleton, Caird, Nettleshi23, and Wallace. Kant's style is careless and involved, vi TRANSLATORS PREFACE. and no wonder that it should be so, if we consider that he wrote down the whole of the Critique in not quite five ioaonths. Now, beside the thread of the argument itself, the safest thread through the mazes of his sentences must be looked for in his adverbs and XJarticles. They, and they only, indicate clearly the true articulation of his thoughts, and they alone im- part to his phrases that peculiar intonation which tells those who are accustomed to that bye-play of language, what the author has really in his mind, and what he wants to express, if only he could find the right way to do it. When reading and critically interpreting Kant's text, I sometimes compared other translations, particularl}^ the EngUsh translations by Haywood and Meiklejohn \ and excellent as I found their renderings, particularly the latter, in many places, I generally observed that, when the thread was lost, it was owing to a neglect of particles and adverbs, though sometimes also to a want of appreciation of the real, and not simply the dictionary meaning, of Glerman words. It is not my intention to write here a criticism of previous trans- lations ; on the contrary, I should prefer to express my obligation to them for several useful suggestions which I have received from them in the course of what I know to be a most arduous task. But in order to give an idea of what I mean by the danger arising from a neglect of adverbs and particles in 1 I discovered too late that Professor MahafFy, in his translation of Kuno Fischer's work on Kant (Longmans, 1866), has given some excellent specimens of what a translation of Kant ought to be. Had I known of them in time, I should have asked to be allowed to in- corporate them in my own translation. TRANSLATORS PREFACE. vii German, I shall mention at least a few of the pas- sages of which I am thinking. On p. 42 1 (484), Kant says : Da also selhst die Aiiflosung clieser Aufgahen niemals in cler Erfahrung vorhommen Jcann. This means, 'As therefore even the solution of these problems can never occur in expe- rience,' i. e. as, taking experience as it is, we have no right even to start such a problem, much less to ask for its solution. Here the particle also implies that the writer, after what he has said before, feels justified in taking the thing for granted. But if we translate, 'Although, therefore, the solution of these problems is unattainable through experience,' we completely change the drift of Kant's reasoning. He wants to take away that very excuse that there exists only some uncertainty in the solution of these problems, by showing that the problems themselves can reaUy never arise, and therefore do not require a solution at all. Kant repeats the same statement in the same page with still greater emphasis, when he says : Die dogniatische Aujidsung ist also nicM etiva un- getviss, sondern unmoglicJi, i. e. ' Hence the dog- matical solution is not, as you imagine, uncertain, but it is impossible.' On p. 421 (485), the syntactical structure of the sen- tence, as well as the intention of the writer, does not al- low of our changing the words so ist es Miiglich gehan- delt, into a question. It is the particle so which requires the transposition of the pronoun {ist es instead of es ist), not the interrogative character of the whole sentence. On p. 42 7 (49 2), loenn cannot be rendered hj although, which is wenn auch in German. Wenn heide nach viii TRANSLATORS PREFACE. em^irischen Gesetzen in einer Erfahrung richhc/ una durchgcingig zusammenhdngen, means, ' If both have a proper and thorough coherence in an experience, according to empirical laws;' and not, 'Although both have,' etc. SoUen is often used in German to express what, according to the opinion of certain people, is meant to be. Thus Kant, on p. 492 (5 70), speaks of the ideals which painters have in their mmds, and die ein nicht mitzutlieilendes Schattenlild Hirer Producte oder audi Beurtheilungen sein sollen, that is, ' which, according to the artists' professions, are a kind of vague shadows only of their creations and criticisms, which cannot be communicated.' All this is lost, if we trans- late, ' which can serve neither as a model for pro- duction, nor as a standard for appreciation.' It may come to that in the end, but it is certainly not the way in which Kant arrives at that conclusion. On p. 536 (625), den einzigvibglichen Betueisgrund {wofern ilherall nur ein si^ecidativer Beweis statt findet) is not incorrectly rendered by ' the only possible ground of proof (possessed by speculative reason) ;' yet we lose the thought implied by Kant's way of ex- pression, viz. that the possibihty of such a speculative proof is very doubtful. The same applies to an expression which occurs on p. 586 (684), ein solches Schema, ah oh es ein wirhliches Wesen ware. Kant speaks of a schema which is con- ceived to be real, but is not so, and this implied meaning is blurred, if we translate ' a schema, which requires us to regard this ideal thing as an actual existence.' In German, if we speak of two things mentioned TRANSLATORS PREFACE. IX together, we do not use letzter in opposition to jener. On p. 256 (295), Kant speaks of the place which is to be assigned, by means of transcendental reflection, to every presentation (Vorstellung), as belonging either to sensibility or to the understanding, and of the in- fluence which that assignation exercises on the proper representation of a given object. He ends by saying: Wodurch jeder Vorstellung ihre Stelle in der ihr ange- messenen ErkenntnissJcraft angewiesen, mithin auch der Einfluss der letzteren aufjene unterschieden tvird, that is, 'Whereby the right place is assigned to each repre- sentation in the faculty of knowledge corresponding to it, and the influence of the latter, i. e, of either faculty of knowledge, upon such representation is determined ; ' not, ' and consequently the influence of the oue faculty upon the other is made apparent.' On p. 608 (712), Kant writes: Methoden, die zioar sonst der Vernunfi, aher nur nicht hier ivol anpassen. This has been translated : ' The methods which are originated by reason, but which are out of place in this sphere.' This, again, is not entirely wrong, but it spoils the exact features of the sentence. What is really meant is : ' Methods which are suitable to reason in other spheres, only, I beheve, not here.' It is curious to observe that Kant, careless as he was in the revision of his text, struck out ivol in the Second Edition, because he may have wished to remove even that slight shade of hesitation which is conveyed by that particle. Possibly, however, tvol may refer to anpassen, i. e. fulchre convenire, the hmitation remain- ing much the same in either case. TKANSLATOR S PREFACE. Docli is a particle that may be translated in many different ways, but it can never be translated by therefore. Thus when Kant writes (Suppl. xiv. § 1 7, note, vol. i. p. 438), folgUcli die Einheit des Bemisst- seyns, als synthetiscJi, aher dock urspriinglich ange- troffen ivird, he means to convey an opposition be- tween synthetical and primitive, i. e. synthetical, and yet primitive. To say 'nevertheless synthetical, and therefore primitive ' conveys the very opposite. It may be a mere accident, yet in a metaphysical argument it must sometimes cause serious incon- venience, if the particle not is either omitted where Kant has it, or added where Kant has it not. It is of small consequence, if not is omitted in such a pas- sage as, for instance, where Kant says in the preface to the Second Edition (vol. i. p. 385), that the obscu- rities of the first have given rise to misconceptions ' without his fault,' instead of ' not without his fault.' But the matter becomes more serious in other places. Thus (Supplement xiv. f 26, vol. i. p. 455) Kant says, olme diese Tauglichkeit, which means, 'unless the cate- gories were adequate for that purpose,' but not, ' if the categories were adequate.' Again (Supplement xvil^. vol. i. p. 466), Kant agrees that space and time cannot be perceived by themselves, but not, that they can be thus perceived. And it must disturb even an atten- tive reader when, on p. 216 (248), he reads that 'the categories must be employed empirically, and cannot be employed transcendentally,' while Kant writes : Ba sie nicht von empiriscJiem Gebraucli sein sollen, und von transcendentalem nicht sein Tibnnen. As regards single words, there are many in German TRANSLATORS PREFACE. XI which, taken in their dictionary meaning, seem to yield a tolerable sense, but which throw a much brighter light on a whole sentence, if they are under- stood in their more special idiomatic application. Thus vorriicken, no doubt, may mean 'to place before,' but Jemandem ettvas vorriicken, means ' to reproach somebody with something.' Hence (vol. i. p. 386) die der rationalen Psycliologie vorgeriiokten Paralogismen does not mean ' the paralogisms which immediately precede the Eational Psychology,' but 'the paralogisms with which Eational Psychology has been reproached.' On p. 41 1 (472), naciihangen cannot be rendered by ' to append.' Er erlaidji der Vermmft idealischen Er- klcirungen der Natur naclizuhdngen means ' he allows reason to indulge in ideal explanations of nature,' but not ' to append idealistic explanations of natural phenomena.' On p. 669 (781), als oh er die hejaJiende PartJiei er- griffen hatte, does not mean 'to attack the position,' but ' to ado]}t the position of the assenting party.' On p. 727 (847), Wie hann ich envarten does not mean, ' How can I desire"?' but, ' How can I expect 1' which may seem to be not very different, but neverthe- less gives a very different turn to the whole argument. I have quoted these few passages, chiefly in order to show what I mean by the advantages which a German has in translating Kant, as compared with any other translator who has derived his knowledge of the language from grammars and dictionaries only. An acciu-ate and scholarlike knowledge of German would, no doubt, suffice for a translation of Xll TRANSLATORS PREFACE. historical or scientific works. But in order to find our way through the intricate mazes of metaphysical arguments, a quick perception of what is meant by the sign-posts, I mean the adverbs and particles, and a natural feeling for idiomatic ways of speech, seem to me almost indispensable. On the other hand, I am fully conscious of the advantages which English translators possess by their more perfect command of the language into which foreign thought has to be converted. Here I at once declare my own inferiority ; nay, I confess that in rendering Kant's arguments in English I have thought far less of elegance, smoothness or rhythm, than of accuracy and clearness. What I have attempted to do is to give an honest, and, as far as possible, a literal translation, and, before all, a translation that ivill construe ; and I venture to say that even to a German student of Kant this English translation will prove in many places more intelligible than the German original. It is difficult to translate the hymns of the Veda and the strains of the Upanishads, the odes of Pindar and the verses of Lucretius ; but I doubt whether the difficulty of turning Kant's metaphysical German into intelligible and construable English is less. Nor do I wish my readers to believe that I have never failed in making Kant's sentences intelligible. There are a few sen- tences in Kant's Critique which I have not been able to construe to my own satisfaction, and where none of the friends whom I consulted could help me. Here all I could do was to give a literal rendering, hoping that future editors may succeed in amending TRANSLATORS PREFACE. XIU the text, and extracting from it a more intelligible sense. Why I thought I ought to translate Kant's Critique. But my friends in blaming me for wasting my time on a translation of Kant's Critique of Pure Reason gave me to understand that, though I might not be quite unfit, I was certainly not specially called upon to undertake such a work. It is triie, no doubt, that no one could have blamed me for not translating Kant, but I should have blamed myself; in fact, I have blamed myself for many years for not doing a work which I felt must be done sooner or later. Year after year I hoped I should find leisure to carry out the long cherished plan, and when at last the Centenary of the publication of Kant's Critik der reinen Vernunft drew near, I thought I was in honour bound not to delay any longer this tribute to the memory of the greatest philosopher of modern times. Kant's Critique has been my con- stant companion through life. It drove me to de- spair when I first attempted to read it, a mere school- boy. At the University I worked hard at it under Weisse, Lotze, and Drobisch at Leipzig, and my first literary attempts in philosophy, now just forty years old, were essays on Kant's Critique. Having once learnt from Kant what man can and what he cannot know, my plan of hfe was very simple, namely, to learn, so far as literature, tradition, and language allow us to do so, how man came to believe that he could know so much more than he XIV TRANSLATORS PREFACE. ever can know in religion, in rajihologj, and in imi- losophy. This required special studies in the field of the most ancient languages and literatures. But though these more special studies drew me away for many years towards distant times and distant countries, whatever purpose or method there may have been in the work of my life, was due to my beginning life with Kant. Even at Oxford, whether I had to lecture on German literature or on the Science of Language, I have often, in season and out of season, been preaching Kant ; and nothing I have missed so much, when wishing to come to an understanding on the great problems of hfe with some of my philosophical friends in England, than the common ground which is supplied by Kant for the dis- cussion of every one of them. We need not be blind worshippers of Kant, but if for the solution of philosophical problems we are to take any well defined stand, we must, in this century of ours, take our stand on Kant. Kant's language, and by lan- guage I mean more than mere words, has become the Lingua franca of modem philosophy, and not to be able to speak it, is like studying ancient phi- losophy, without being able to speak Aristotle, or modern philosophy, without being able to speak Descartes. What Rosenkranz, the greatest among Hegel's disciples, said in 1838, is almost as true to-day as it was then : Engldnder, Franzosen und Italiener tnilssen, wenn sie vorivdrts wollen, denselben Schritt thun, den Kant schon 178 1 maclite. Nur so. Jconnen sie sich von ihrer dermaligen sclilechten Meta- TRANSLATORS PREFACE. XV physih und den aus einer solcJien sich ergebenden scMechten Consequenzen hefreien. It is hardly necessary at the present day to produce any arguments in support of such a view. The num- ber of books on Kant's philosophy, published during the last century in almost every language of the world \ speaks for itself. There is no single philosopher of any note, even among those who are decidedly opposed to Kant, who has not acknowledged his pre-eminence among modern philosophers. The great systems of Fichte, Schelling, Hegel, Herbart, and Schopenhauer branched off from Kant, and now, after a century has passed away, people begin to see that those systems were indeed mighty branches, but that the leading shoot of jDhilosophy was and is still — Kant. No truer word has lately been spoken than what, I believe, was first said by Professor Weisse^, in the Philosophical Society at Leipzig, of which I was then a member, and was again more strongly enforced by my friend and former .colleague. Professor Liebmann of Strassburg, that, if philosophy wishes to go forward, it must go back to Kant. U faut reculer, pour mieux sauter. Lange, in his History of Materialism, calls Kant the Copernicus of modern philosophy ; aye, Kant himself was so fully conscious of the decentralising character of his system that he did not hesitate to compare his work with that of Copernicus =* But if Kant was right in his estimate of his own philosophy, it cannot be ' During the first ten years after the appearance of the Critique, three hundred publications have been counted for and against Kant's philosophy. See Vaihinger, Kommentar, i. p. 9. ^ See Julius Walter, Zum Gedachtniss Kant's, p. 28. ' See Supplement II, vol. i. p. 370. XVI TRANSLATOR S PREFACE. denied that, with but few, though memorable excep- tions, philosophy in England is still Ante-Copernican. How little Kant is read by those who ought to read him, or how little he is understood by those who venture to criticise him, I never felt so keenly as when, in a controversy which I had some time ago with one of the most illustrious of English philosophers, I was told that space coidd not be an a jpriori intuition, because we may hear church-bells, without knowing where the belfry stands. Two philosophers, who both have read Kant's Critique, may differ from each other diametrically, but they will at least understand each other. They will not fire at each other like some of the German students who, for fear of killing their adversary, fire their pistols at right angles, thus endangering the life of their seconds rather than that of their adversaries. This will explain why, for a long time, I have felt personally called upon to place the classical work of Kant within the reach of all philosophical readers in England, and in such a form that no one could say any longer that he could not construe it. I thought for a time that Professor Caird's excellent work ' On the Philosophy of Kant,' had relieved me of this duty. And, no doubt, that work has told, and has opened the eyes of many people in England and in America to the fact that, whatever we may think of all the outworks of Kant's philosophy, there is in it a central thought which forms a real rest and an entrenched ground on the onward march of the human intellect. But it is a right sentiment after all, that it is TRANSLATOES PREFACE. XVU better to read a book than to read about it, and that, as my friend Stanley used to preach again and again, we should never judge of a book, unless we have read the whole of it ourselves. I therefore pledged myself to finish a new translation of Kant's Critique as my contribution to the celebration of its centenary, and though it has taken more time and more labour than I imagined, I do not think my time or my labour will have been wasted, if only people in England, and in America too, will now read the book that is a hundred years old, and yet as young and fresh as ever. So far I have spoken of myself, and more perhaps than a wise man at my time of life ought to do. But I have still to say a few words to explain why I think that, if the time which I have bestowed on this undertaking has not been wasted, others also, and not philosophers by profession only, will find that I have not wasted their time by inducing them at the present time to read Kant's masterwork in a faithful English rendering. Why a study of Kant's Critique seemed necessary at present. It is curious that in these days when the idea of development, which was first elaborated by the students of philosophy, language, and religion, and afterwards applied with such brilliant success to the study of nature also, should now receive so httle favour from the very sciences which first gave birth to it. Long before we heard of evolution in nature, we read of the dialectical evolution of thought, and VOL. I. b XVm TRANSLATOES PREFACE. its realisation in history and nature. The history of philosophy was then understood to represent the con- tinuous development of philosophical thought, and the chief object of the historian was to show the necessity mth which one stage of philosophical thought led to another. This idea of rational development, which forms a far broader and safer basis than that of natu- ral development, is the vital principle in the study of the human mind, quite as much, if not more, than in the study of nature. A study of language, of my- thology, of religion, and philosophy, which does not rest on the principle of development, does not deserve the name of a science. The chief interest which these sciences possess, is not that they show us isolated and barren facts, but that they show us their origin and growth, and explain to us how what is, was the neces- sary result of what was. In drawing the stemma of languages, mythological formations, religious beliefs, and philosophical ideas, science may go wrong, and often has gone wrong. So have students of nature in drawing their stemmata of plants, and animals, and human beings. But the principle remains true, for all that. In spite of all that seems to be accidental or arbitrary, there is a natural and intelli- gible growth in what we call the creations of the human mind, quite as much as in what we call the works of nature. The one expression, it may be said, is as mythological as the other, because the category of substance cannot apply to either nature or mind. Both, however, express facts which must be ex- plained ; nay, it is the chief object of science to explain them, and to explain them genetically. Is TRANSLATORS PBEPACE. XIX Aristotle possible or intelKgible without Plato 1 Is Spinoza possible or intelligible without Descartes 1 Is Hume possible or intelligible without Berkeley ? Is Kant possible or intelligible without Hume ? These are broad questions, and admit of one answer only. Bvit if we have once seen how the broad stream of thought follows its natural bent, flows onward, and never backward, we shall understand that it is as much the duty of the science of thought to trace unbroken the course of philosophy from Thales to Kant, as it is the duty of natural science to trace the continuous development of the single cell to the complicated organism of an animal body, or the possible metamorphosis of the Hipparion into the Hippos. What I wanted, therefore, as an introduction to my translation of Kant's Critique, was a pedigree of philosophical thought, showing Kant's ancestors and Kant's descent. Here, too. Professor Caird's work seemed to me at one time to have done exactly what I wished to see done. Valuable, however, as Pro- fessor Caird's work is on all sides acknowledged to be, I thought that an even more complete list of Kantian ancestors might and should be given, and (what weighed even more with me), that these ances- tors should be made to speak to us more in their own words than Professor Caird has allowed them to do. At my time of life, and in the midst of urgent work, I felt quite unequal to that task, and I there- fore applied to Professor Noir^ who, more than any other philosopher I know, seemed to me qualified to b2 XX teanslatob's pkeface. carry out that idea. Kant's philosophy, and more particularly the antecedents of Kant's philosophy, had been his favourite study for life, and no one, as I happened to know, possessed better materials than he did for giving, in a short compass, the ijmssinia verba by which each of Kant's ancestors had made and marked his place in the history of thought. Professor Noire readily complied with my request, and supplied a treatise which I hope will fully accomplish what I had in view. The translation was entrusted by him to one of the ijiost distinguished translators of pliilo- sophical works in England, and though the exactness and gracefulness peculiar to Professor Noire's German style could hardly have full justice done to them in an English rendering, particularly as the constant introduction of the verba ipsissima of various authors cannot but disturb the unity of the diction, I hope that many of my English readers will feel the same gratitude to him which I have here to express for his kind and ready help. If, then, while making allowance for differences of opinion on smaller points, we have convinced our- selves that Kant is the last scion of that noble family of thinkers which Professor Noir^ has drawn for us with the hand of a master, what follows ? Does it follow that we should all and on all points become Kantians, that we should simply learn his philosophy, and be thankful that we know now all that can be known about the Freedom of the Will, the Immor- tality of the Soul, and the Existence of God ? Far from it. No one would protest more strongly than Kant against what he himself calls ' learning philosophy/ TKANSLATOBS PREFACE. Xxi as opposed to ' being a philosopher.' All I contend for is that, in our own modern philosophy, the work once for all done by Kant can be as little ignored as the work done by Hume, Leibniz, Berkeley, Locke, Spinoza, and Descartes. I do not deny the historical importance of the Post-Kantian systems of philosophy, whether of Fichte, Schelling, Hegel, Herbart, or Scho- penhaiier in Germany, of Cousin in France, or of Mill in England. But most of these philosophers recog- nised Kant as their spiritual father '. Even Comte, ignorant as he was of German and German philo- sophy, expressed his satisfaction and pride when he discovered how near he had, though unconsciously, approached to Kant's philosophy 2. Some years ago ' Julius Walter, Zum Gedachtniss Kant's, p. 27. ^ ' J'ai lu et relu avec un plaisir infini le petit traits de Kant (Idee zu einer allgemeinen Gesohichte in weltbiirgerlicher Absicht, 1784) ; il est prodigieux pour I'^poque, et meme, si je I'avais comiu six ou sept ans plus tot, il m'aurait 6pargne de la peine. Je suis charm6 que vous I'ayez traduit, il pent tres-efficacement oontribuer ci preparer les esprits a, la philosophie positive. La oonceptiovi generale ou au moins la m6thode y est encore m^tapbysique, mais les details niontrent a cliaque instant I'esprit positif. J'avais tou- jours regard^ Kant non-seulement comma une tres-forte tete, mais comme le metaphysicien le plus rapproch^ de la pbilosophie positive. .... Pour moi, je ne me trouve jusqu'a present, apres cette lecture, d'autre valeur que celle d'avoir systematise et arrete la conception ebauoh^e par Kant a mon insu, ce que je dois surtout a Feducatiou scientifique ; et meme le pas le plus positif et le plus distinct que j'ai fait apres lui, me semble seulement d'avoir decouvert la loi du passage des idees humaines par les trois etats tljiiologique, meta- physique, et scientifique, loi qui me semble etre la base du travail dont Kant a conseille I'execution. Je rends grace aujourd'hui a mon defaqt d'^rudition ; car si mon travail, tel qu'il est maintenant, avait et6 pr^c^d^ chez moi par I'etude du traits de Kant, il aurait, k mes propres yeux, beaucoup perdu de sa valeur.' See Auguste Comte, par E. Littre, Paris, 1864, p. 154; Lettre de Comte a M. d'Eichthal, 10 Dec. 1824. Xxii TEANSLATORS PRErACE. I ventured to point out that, as far as I could judo-e, amid the varying aspects of his philosophical writings, Mr. Herbert Spencer also, in what he calls his Transfigured Eealism, was not very far from Kant's fundamental position. Mr. Herbert Spencer, however, has repudiated what I thought the highest compliment that could be paid to any writer on philosophy, and I feel bound therefore to withdraw my conjecture. But although, whether consciously or unconsciously, all truly important philosophers have, since the pub- lication of the Critique of Pure Reason, been more or less under the spell of Kant, and indirectly of Hume and Berkeley also, this does not mean that they have not asserted their right of reopening questions which seemed to be solved and settled by those heroes in the history of human thought. Only, if any of these old problems are to be taken up again, they ought at least to be taken up where they were last left. Unless that is done, philosophy will be- come a mere amusement, and will in no wise mark the deep vestiges in the historical progress of the human intellect. There are anachronisms in philo- sophy, quite as much as in other sciences, and the spirit in which certain philosophical problems have of late been treated, both in England and in German v, is really no better than a revival of the Ptolemaic system would be in astronomy. No wonder, there- fore, that in both countries we should meet with constant complaints about this state of philosophical anarchy. Mr. Challis in one of the last numbers of the Contemjjorary Review (November, 1881), writes : TEANSLATOES PEEPACE. XXlil ' It is another familiar fact, a mucli more important one, that the present state of philosophy is exactly parallel to the present state of theology, — a chaos of conflicting schools, each able to edify itself without convincing any other, every one regarding aU the rest, not as witnesses against itself, but as food for dialectical powder and shot. The impartial by- stander sees no sign that we are now nearer to agreement than in the days of Varro ; though the enthusiast of a school expects the world to be all some day of his opinion, just as the enthusiast of a sect believes vaguely in an ultimate triumph of his faith.' Exactly the same complaint reaches us from the very country where Kant's voice was once so powerful and respected, then was silenced for a time, and now begins to be invoked again for the purpose of re- storing order where all seems confusion. ' Since the year 1 840,' writes Dr. Vaihinger, ' there has been hopeless philosophical anarchy in Germany. There were the disciples of ScheUing, Hegel, Her- bart, and Schopenhauer, and, by their side, the founders and defenders of many unknown systems of philosophy. Then followed the so-called Real- Idealists, or Ideal-Realists, whcT distilled a philo- sophical theism out of the pantheism of greater thinkers, and, as their antipodes, the Materialists, who on the new discoveries of natural science founded the saddest, shallowest, and emptiest system of philosophy 1.' 1 Vaihinger, Zum Jubilaum von Kant's Kritik der reinen Vernunft, p. 1 1 . XXIV TRANSLATORS PREFACE. In England and America, even more than in Ger- many, I believe that a study of Kant holds out the best hope of a philosophical rejuvenescence. In Germany a return to Kant is a kind of Renaissance ; in England and America Kant's philosophy, if once thoroughly understood, will be, I hope, a new birth. No doubt there are, and there have been in every country of Europe some few honest students who perfectly understood Kant's real position in the onward march of human thought. But to the most fertile writers on philosophy, and to the general public at large, which derives its ideas of philosophy from them, Kant's philosophy has not only been a terra incognita, but the very antipodes of what it really is. Mr. Watson, in his instruc- tive work, ' Kant and his English Critics/ is per- fectly right when he says that, till very lately, Kant was regarded as a benighted a j)riori phi- losopher of the dogmatic type, afflicted with the hallucination that the most important part of our knowledge consists of innate ideas, lying in the depths of consciousness, and being capable of being brought to the light by pure introspection.' That Kant was the legitimate successor of Hume on one side, and of Berkeley on the other, was hardly con- ceived as possible. And thus it has happened that English philosophy, in spite of the large number of profound thinkers and brilliant writers who have served in its ra,nks during the last hundred years, has not yet risen above the level of Locke and Hume. No one can admire more than I do the dashing style in which some of the most popular TRANSLATORS PREFACE. XXV writers of our time have ridden up to the very muzzles of the old philosophical problems, but if I imagine Kant looking back from his elevated position on those fierce and hopeless onslaughts, I can almost hear him say what was said by a French general at Balaclava : C'est magnifique, — niais ce nest pas la guerre. Quite true it is that but for Hume, -and but for Berkeley, Kant would never have been, and philosophy would never have reached the heights which he occupies. But, after Kant, Hume and Berkeley have both an historical significance only. They represent a position which has been conquered and fortified, and has now been deliberately left behind. Professor Noire, when he had written for this work the antecedents of Kant's philosophy, sent me another most valuable contribution, containing a full analysis of that philosophy, considered not only as the continuation, but as the fulfilment of all other j)hilosophical systems, and more particularly of the systems of Berkeley and Hume. For that work it was unfortunately impossible to find room in these volumes ; but I am glad to know that it will not be withheld, in German at least, from those who, both in England and in Germany, have learnt to appreciate Professor Noird's accurate and luminous statements. Leaving therefore the task of tracing minutely the intimate relation between Kant and his predecessors to the more experienced hand of my friend, I shall here be satisfied with pointing out in the broadest way the connection, and, at the same time, the diametrical opposition between Kant XXVI TRANSLATORS PREFACE. and those two great heroes of speculative thought, Berkeley and Hume. Berkele}- holds that all knowledge that seems to come to us from without through the senses or through experience is mere illusion, and that truth exists in the ideas of the pure understanding and of reason only. Kant proves that all knowledge that comes to us from pure understanding and from pure reason only is mere illusion, and that truth is impossible v/ithout experience. Hume holds that true causality is impossible, whether in experience or beyond experience. Kant proves that experience itself is impossible without the category of causality, and, of course, without several other categories also which Hume had overlooked, though they possess exactly the same character as the concept of causality^. The gist of Kant's philosophy, as opposed to that of Hume, can be expressed in one line : That without which experience is impossible, cannot be the result of ex- perience, though it must never be applied beyond the limits of possible experience. Such broad statements and counter-statements may seem to destroy the finer shades of philosophical thought, yet m the end even the most complicated and elaborate systems of philosophy rest on such broad foundations ; and what we carry about with us of Plato or Aristotle, of Descartes or Leibniz, consists ^ This is Kant's statement, though it is not quite accurate. See Adamson, On the Pliilosophy of Kant, p. 202. That Kant knew Hume's Treatise on Human Nature seems to follow from Hamann's Metakritilc iiber den Purismus der reinen Yertmn/t, p. 3, note. TRANSLATORS PREFACE. XXVll in the end of little more than a few simple out- lines of the grand structures of their philosophical thoughts. And in that respect no system admits of being traced in simpler and broader outlines than that of Kant. Voluminous and complicated it is, and yet Kant himself traces in a few lines the outcome of it, when he says (Critique, p. 712 (830) : ' But it will be said, is this really all that pure reason can achieve, in opening prospects beyond the limits of experience 1 Nothing more than two articles of faith ? Surely even the ordinary understanding could have achieved as much without taking counsel of philosophers ! ' I shall not here dwell on the benefits,' he answers, ' which, by the laborious efforts of its criticism, phi- losophy has conferred on human reason, granting even that in the end they should turn out to be merely negative. On this point something will have to be said in the next section. But, I ask, do yovi really require that knowledge, which con- cerns all men, should go beyond the common un- derstanding, and should be revealed to you by philosophers only 1 The very thing which you find fault with is the best confirmation of the correct- ness of our previous assertions, since it reveals to us, what we could not have grasj^ed before, namely, that in matters which concern all men without dis- tinction, nature cannot be accused of any partial distribution of her gifts ; and that, with regard to the essential interests of human nature, the highest philosophy can achieve no more than that guidance which nature has vouchsafed even to the meanest understanding.' XXVIU TRANSLATORS PREFACE. I hope that the time will come when Kant's works, and more particularly his Critique of Pure Reason, will be read, not only by the philosopher by pro- fession, but by everybody who has once seen that there are problems in this life of ours the solu- tion of which alone makes life worth living. These problems, as Kant so often tells us, are all the making of reason, and what reason has made, reason is able to unmake. These problems represent in fact the mythology of philosophy, that is, the influence of dymg or dead language on the living thought of each successive age ; and an age which has found the key to the ancient mythology of religion, will know where to look for the key that is to unlock the mythology of pure reason. Kant has shown us what can and what cannot be known by man. What re- mains to be done, even after Kant, is to show how man came to believe that he could know so much more than he can know, and this will have to be shown by a Critique of Language \ How strange it is that Kant's great contemporary, ' the Magus of the North,' should have seen this at once, and that for a whole century that thought has ' What I mean by this, may be seen in the last Lecture of the Second Series of my Lectures on the Science of Language, delivered iu 1867 (ed. 1880, vol. ii. p. 612 seq.) ; in my article On the Origin of Reason, ContemjMrary Bevieiv, February, 1878; my Lectures on Mr. Darwin's Philosophy of Language, Fraser's Magazine, May, 1873 ; also in Professor Noire's works, Ber Ursprung der Sprache, 1877; and Max Mailer and the Philosophy of Language (Long- mans, 1879). One important problem, in the solution of which I differ from Kant, or rather give a new application to Kant's own l>rinciples, has been fully treated in my Ilihbert Lectures, 1878 pp. 30 seq. TRANSLATOR S PREFACE. XXIX remained dormant. ' Language,' Hamaun writes, ' is not only tte foundation for the whole faculty of thinking, but the central point also from which pro- ceeds the misunderstanding of reason by herself.' And again 1: 'The question with me is not, What is Reason 1 but, What is Language ? And here I suspect is the ground of all paralogisms and anti- nomies with which Reason has been charged.' And again : ' Hence I feel almost inclined to believe that our whole philosophy consists more of language than of reason, and the misunderstanding of number- less words, the prosopopoeias of the most arbitrary abstraction, the antitheses t^? y^evSojvvfj.ov 'yvwa-ecos ; nay, the commonest figures of speech of the sensus communis have produced a whole world of problems, which can no more be raised than solved. What we want is a Grammar of Reason.' That Kant's Critique will ever become a popular book, in the ordinary sense of the word, is impos- sible ; but that it will for ever occupy a place in the small tourist's library which every thoughtful travel- ler across this short life's journey will keep by his side, I have no doubt. Kant, it must be admitted, was a bad writer, but so was Aristotle, so was Descartes, so was Leibniz, so was Hegel ; and, after a time, as in climbing a mountain, the very roughness of the road becomes an attraction to the traveller. Besides, though Kant is a bad builder, he is not a bad archi- tect, and there will be few patient readers of the Critique who will fail to understand Goethe's ex- pression that on reading Kant, or rather, I should ' Gildemeister, Hamann's Leben und Schriften, vol. iii. p. 71. XXX TRANSLATORS PREFACE. say, on reading Kant again and again, we feel like stepping into a lighted room. I have tried hard, very hard, to remove some of the darkness which has hitherto shrouded Kant's masterwork from English readers, and though I know how often I have failed to satisfy myself, I still hope I shall not have laboured quite in vain. Englishmen who, in the turmoil of this century, found leisure and mental vigour enough to study once more the thoughts of Plato, and perceived their bearing on the thoughts of our age, may well brace themselves to the harder work of discovering in Kant the solution of many of the oldest problems of our race, problems which, with most of us, are still the problems of yester- day and of to-day. I am well aware that for Kant there is neither the prestige of a. name, such as Plato, nor the cunning of a translator, such as Jowett. But a thinker who in Germany could make him- self Hstened to during the philosophical apathy of the Wolfian age, who from his ultima Thule of Konigsberg could spring forward to grasp the rudder of a vessel, cast away as unseaworthy by no less a captain than Hume, and who has stood at the helm for more than a century, trusted by all whose trust was worth having, will surely find in England, too, patient listeners, even though they might shrink, as yet, from embarking in his good ship in their passage across the ocean of life. Kant's Metaphysic in relation to Physical Science. We live in an age of physical discovery, and of complete philosophical prostration, and thus only can TRANSLATORS PREFACE. XXXI we account for the fact that physical science, and, more particulaily, physiology, should actually have grasped at the sceptre of philosophy. Nothing, I believe, could be more disastrous to both sciences. No one who knows my writings wiU suspect me of undervaluing the progress which physical studies have made in our time, or of ignoring the light which they have shed on many of the darkest problems of the mind. Only let us not unnecessarily move the old landmarks of human knowledge. There always has been, and there always must be, a hne of demarcation between physical and metaphysical investigations, and though the former can illustrate the latter, they can never take their place. Nothing can be more in- teresting, for instance, than recent researches into the exact processes of sensuous perception. Optics and Acoustics have carried us deep into the inner workings of our bodily senses, and have enabled us to understand what ive call colours and sounds, as vibra- tions, definite in number, carried on from the outer organs through vibrating media to the brain and the inmost centre of all nervous activity. Such observa- tions have, no doubt, made it more intelligible, even to the commonest understanding, what metaphysicians mean when they call all secondary qualities subjective, and deny that anything can be, for instance, green or sweet, anywhere but in the perceiving subject. But the idea that these physical and physiological researches have brought us one inch nearer to the real focus of subjective perception, that any move- ment of matter could in anyway explain the simplest sensuous perception, or that behind the membranes XXXU TRANSLATORS PREFACE. and nerves we should ever catcli hold of what we call the soul, or the I, or the self, need only to be stated to betray its utter folly. That men like Helmholtz and Du Bois-Keyniond should find Kant's metaphysical platform best adapted for supporting their physical theories is natural enough. But how can any one who weighs his words say that the modern physiology of the senses has in any way supplemented or im- proved Kant's theory of knowledge^ ? As well might we say that spectrum analysis has improved our logic, or the electric light supplemented our geometry. 'Empirical psychology,' as Kant says, 'must be en- tirely banished from metaphysic, and is excluded from it by its very idea ^.' Metaphysical truth is wider than .physical truth, and the new discoveries of physical observers, if they are to be more than merely contingent truths, must find their appointed place and natural refuge within the immoveable limits traced by the metaphysician. It was an unfortunate accident that gave to what ought to have been called pro-physical, the name of meta- physical science, for it is only after having mastered the principles of metaphysic that the student of nature can begin his work in the right spirit, know- ing the horizon of human knowledge, and guided by principles as unchangeable as the pole star. It would be childish to make this a question of rank or precedence; it is simply a question of work and order. It may require, for instance, a greater effort, ^ See Noir^, in Die Gegenwart, June 23, 188 1. ^ Critique, p. 728 (848). TEANSLATOE S PRErACK. SXXIU and display more brilliant mental qualities, to show that nature contains no traces of repeated acts of special creation, than to prove that such a theory would make all unity of experience, and consequently all science, impossible. But what are all the negative arguments of the mere observer without the solid foundation supplied by the metaphysician 1 And with how much more of tranquil assurance would the geologist pursue his observations and develop his conclusions, if he just remembered these few lines of Kant : ' When such an arising is looked upon as the effect of a foreign cause, it is called creation. This can never be admitted as an event among phenomena, because its very possibility would destroy unity of experience \' What can have been more delightful to the un- prejudiced observer than the gradiial diminution of the enormous number of what were called by students of nature, who had never troubled their heads about the true meaning of these terms, genera and species ? But when the true meaning, and thereby the true origin, of genera and species was to be determined, is it not stran2;e that not one word should ever have been said on the subjective character of these terms ? Whatever else a genus or species may be, surely they are, first of all, concepts of the understanding, and, without these concepts, whatever nature might pre- sent to us, nothing would ever be to us a genus or a species. Now the genus and species, in that restricted sense, as applied to organic beings, represent only 1 Critique, p. i8o (206). VOL. I. XXXIV TRANSLATOR S PREFACE. one side of that fundamental process on which all thought is founded, namely, the conception of the General and the Special. Here, again, a few pages of Kant ^ would have shown that the first thing to be explained is the j^rocess by which we conceive the genus or the general, and tliat the only adequate ex- planation of it is what Kant calls its transcendental deduction, i.e. the proof that, without it, experience itself would be impossible ; and that therefore, so far from being a concejot abstracted from experience, it is a sine qua non of experience itself. If this is once clearly understood, it will be equally understood that, as we are the makers of all concepts, we are also the makers of genera and sjoecies, and that long before logicians came to define and deface these terms, they were what we now are anxious to make them again, terms for objects which have either a common origin, or a common form. Long before Aristotle forced the terms yevoi and elSog to assume a subordinate relation to each other, lan- guage, or the historical logic of the human race, had formed these terms, and meant them to be co-ordinate. Genos meant kin, and the first genos was the gens or the family, comprehending individuals that could claim a common ancestor, though differing in appear- ance as much as a grandfather and a babe. Mdos or species, on the contrary, meant appearance or form, and the first eidos was probably the troop of warriors, comprehending individuals of uniform appearance, nothing being asserted as to their common orio-in. This was the historic or prehistoric beginnino- of these ' Critique of Pure Keason, p. 559 (pp. 652 seq.). TRANSLATOR S PREFACE. XXXV two fundamental categories of thought — and what has the theory of evolution really done for them ? It has safely brought them back to their original meaning. It has shown iis that we can hold together, or compre- hend, or conceive, or classify, or generalise or speak in two ways, and in two ways only — either by common descent (genealogically), or by common appearance (morphologically). Difference of form is nothing, if we classify genealogically, and difference of descent is nothing, if we classify morphologically. What the theory of evolution is doing for us is what is done by every genealogist, ay, what was done in ancient time by every paterfamilias, namely, to show by facts that certain individuals, however different from each other in form and appearance, had a common ancestor, and belonged therefore to the same family or kin. In every case where such proof has been given, we gain in reality a more correct general concept, i. e. we are able to think and to speak better. The process is the same, whether we trace the Bourbons and Valois back to Hugo Capet, or whether we derive the Hippos and the Hipparion from a common ancestor. In both cases we are dealing with facts and with facts only. Let it be established that there is no missing link between them, or between man and monkey, and we shall simply have gained a new concept, as we should gain a new concept by establishing the unbroken continuity of the Apostolic succession. Only let us see clearly that in physical and his- torical researches, too, we are dealing with facts, and with facts only, which cannot excite any pas- sion, and that the wider issues as to the origin of c 2 XXXvi TRANSLATORS PREFACE. genera and species belong to a different sphere of human knowledge, and after having been debated for centuries, have been determined once for all by Kant s Critique of Pure Keason. If one remembers the dust-clouds of words that were raised when the question of the origin of species was mooted once more in our days, it is truly re- freshing to read a few of Kant's calm pages on that subject, written one hundred years ago. ' Reason \' he writes, ' prepares the field for the understanding, ' 1st. Through the principle of homogeneousness of the manifold as arranged under higher genera ; ' 2ndly. Through the principle of the variety of the homogeneous in lower species ; to which, ' Srdly, it adds a law of affinity of all concepts, which requires a continual transition from every species to every other species, by a gradual increase of diversity. We may call these the principles of homo- geneousness, of sjieciflcation and oi continuity of forms.' And with reference to the practical application of these metaphysical principles to the study of nature, he writes again with true philosophical insight ^ : ' I often see even intelligent men quarrelling with each other about the characteristic distinctions of men, animals, or plants, nay, even of minerals, the one admitting the existence of certain national characteristics, founded on descent, or decided and inherited differences of famihes, races, etc., while others insist that nature has made the same provision for all, and that all differences are due to accidental environment. But ' Critique, p. 564 (657). ^ Ibid. p. 572 (667), TRANSLATORS PREFACE. XXXVU they need only consider the pecuHar character of the matter, in order to understand that it is far too deeply hidden for both of them to enable them to speak from any real insight into the nature of the object. It is nothing but the twofold interest of reason, one party cherishing the one, another party the other, or pre- tending to do so. But this difference of the two maxims of manifoldness and unity in nature, may easily be adjusted, though as long as they are taken for objective knowledge they cause not only disputes, but actually create impediments which hinder the progress of truth, until a means is found of re- conciling the contradictoiy interests, and thus giving satisfaction to reason. ' The same applies to the assertion or denial of the famous law of the continuous scale of created beings, first advanced by Leibniz, and so cleverly trimmed up by Bonnet. It is nothing but a carrying out of the principle of affinity resting on the interest of reason, for neither observation, nor insight into the con- stitution of nature could ever have supplied it as an objective assertion. The steps of such a ladder, as far as they can be supplied by experience, are far too wide apart from each other, and the so-called small differences are often in nature itself such wide gaps, that no value can be attached to such observations as revealing the intentions of nature, particularly as it must always be easy to discover certain similarities and approximations in the great variety of things. The method, on the contrary, of looking for order in nature, according to such a principle, and the maxim of admitting such order (though it may be uncertain xxxviii translator's preface. where and how far) as existing in nature in general, is certainly a legitimate and excellent regulative principle of reason, only that, as such, it goes far beyond where experience or observation could follow it. It only indicates the way which leads to sys- tematical unity, but does not determine anything beyond.' I know, of course, what some of my philosophical friends will say. ' You speak of thoughts,' they will say, ' we speak of facts. You begin with the general, we begin with the particular. You trust to reason, we trust to our senses.' Let me quote in reply one of the most positive of positive philosophers, one who trusts to the senses, who begins with the particular, and who speaks of facts. CondiUac in his famous ' Essai sur I'Origine des Connaissances humaines,' writes : ' Soit que nous nous ^levions, pour parler metaphoriquement, jusque dans les cieux, soit que nous descendions dans les ablmes, nous ne sortons pas de nous-m^mes ; et ce n'est jamais que notre pensee que nous apercevons.' This was written in 1746. And what applies to these, applies to almost all other problems of the day. Instead of being dis- cussed by themselves, and with a heat and haste as if they had never been discussed before, they should be brought back to the broader ground from which they naturally arise, and be treated by the light of true philosophy and the experience gained in former ages. There is a solid ground formed by the thoughts of those who came before us, a kind of intellectual humus on which we ourselves must learn to march on cautiously, yet safely, without needing those high TRANSLATORS PREFACE. XXXIX stilts which, seem to lift our modern philosophers above the level of Locke, and Hume, and Kant, and promise to enable them to advance across the un- known and the unknowable with wider strides than were ever attempted bv such men as Faraday, or Lyell, or Darwin, but which invariably fall away when they are most needed, and leave our bold speculators to retrace their steps as best they can. Kant's Philosophy as judged by History. If my translation of Kant were intended for a few professional philosophers only, I should not feel bound to produce any credentials in his favoixr. But the few true students of philosophy in England do not want a translation. They would as little attempt to study Kant, without knowing German, as to study Plato, without knowing Greek. What I want, and what I hope for is that that large class of men and women whose thoughts, consciously or unconsciously, are stiU rooted in the philosophy of the last century, and who still draw their intellectual nutriment from the philosophical soil left by Locke and Hume, should know that there is a greater than Locke and Hume, though himself the avowed pupil and the truest admirer of those powerful teachers. Kant is not a man that requires testimonials ; we might as well require testimonials of Plato or Spinoza. But to the English reader it may be of interest to hear at least a few of the utterances of the great men whose merit it is to have discovered Kant, a discovery that may well be called the dis- covery of a new world. xl teanslator's preface. What Goethe said of Kant, we have mentioned before. Schiller, after having declared that he was determined to master Kant's Critique, and if it were to cost him the whole of his hfe, says: 'The funda- mental ideas of Kant's ideal philosophy will remain a treasure for ever, and for their sake alone we ought to be grateful to have been born in this age.' Strange it is to see how orthodox theologians, from mere laziness, it would seem, in mastering Kant's doc- trines, raised at once a clamour against the man who proved to be their best friend, but whose last years of life they must needs embitter. One of the most religious and most honest of Kant's contempo- raries, however, Jung Stilling, whose name is well known in England also, quickly perceived the true bearing of the Critique of Pure Eeason. In a letter, dated March i, 1789, Jung Stilling writes to Kant: 'You are a great, a very great instrument in the hand of God. I do not flatter, — but your philosophy will work a far greater, far more general, and far more blessed revolution than Luther's Eeform. As soon as one has well comprehended the Critique of Eeason, one sees that no refutation of it is possible. Your philosophy must therefore be eternal and unchange- able, and its beneficent effects will bring back the religion of Jesus to its original purity, when its only purpose was — holiness.' Fichte, no mean philosopher himself, and on many points the antagonist of Kant, writes : ' Kant's phi- losophy will in time overshadow the whole human race, and call to life a new, more noble, and more worthy generation.' translator's preface. xli Jean Pavil Friedrich Ptichter speaks of Kant 'not only as a light of the world, but as a whole solar system in one.' With more suppressed, yet no less powerful ap- preciation Wilhelm von Humboldt writes of him : ' Some things which he demolished will never rise again ; some things which he founded will never perish again. A reform such as he carried through is rare in the history of philosophy.' Schopenhauer, the most fearless critic of Kant's Critique, calls it ' the highest achievement of human reflection.' What he has written of Kant is indis- pensable indeed to every student of the Critique, and I deeply regret that I could not have added to my translation of Kant a translation of Schopen- hauer's critical remarks. I must add, however, one paragraph : ' Never,' Schopenhauer writes in his Parerga (1,183), 'never will a philosopher, without an independent, zealous, and often repeated study of the principal works of Kant, gain any idea of this most important of all philosophical phenomena. Kant is, I believe, the most philosophical head that nature has ever pro- duced. To think with him and according to his manner is something that cannot be compared to anything else, for he possessed such an amount of clear and quite pecuhar thoughtfulness as has never been granted to any other mortal. We are enabled to enjoy this with him, if, initiated by patient and serious study, we succeed, while reading the pro- foundest chapters of the Critique of Pure Eeason, in forgetting ourselves and thinking really with xlii translator's preface. Kant's own head, thus being lifted high above our- selves. If we go once more through the Principles of Pure Pteason, and, more particularly, the Analogies of Experience, and enter into the deep thought of the synthetical unity of apperception, we feel as if lifted miraculously and carried away out of the dreamy existence in which we are here lost, and as if holding in our hands the very elements out of which that dream consists.' If, in conclusion, we look at some of the historians of modern philosophy, we find Erdmann, though a follower of Hegel, speaking of Kant as ' the Atlas that supports the whole of German philosophy.' Fortlage, the Nestor of German philosophers S who wrote what he calls a Genetic History of Philosophy since Kant, speaks of him in the following terms : ' In one word, Kant's system is the gate through which everything that has stirred the philosophical world since his time, comes and goes. It is the Universal Exchange where all circulating ideas flow together befoi'e they vanish again in distant places. It is the London of philosophy, sending its ships into every part of the world, and after a time receiving them back. There is no place in the whole globe of human thought which it has not visited, explored, and colonised.' In more homely language Professor Caird ex- presses much the same idea of Kant's philosophy, when he says (p. 120) : ' So much has Kant's fertile idea changed the aspect of the intellectual world, that there is not a single problem of philosophy that ^ He died November, i88i. TEANSLATOBS PREFACE. xlm does not meet us with a new face ; and it is perhaps not unfair to say, that the speculations of all those who have not learned the lesson of Kant, are beside the point.' Dr. Vaihinger, who has devoted his life to the study of Kant, and is now bringing out a com- mentary in four volumes on his Critique of Pure Reason \ sums up his estimate in the following- words : ' The Critique is a work to which, whether we look to the grandeur of conception, or the ac- curacy of thought, or the weight of ideas, or the power of language, few only can be compared — possibly Plato's Eepublic, Aristotle's Metaphysics, Spinoza's Ethics — none, if we consider their lasting effect, their penetrating and far-reaching influence, their wealth of thought, and their variety of sug- gestions ^.' Nearly the same judgment is repeated by Va- cherot ^, who speaks of the Critique as ' un livre immortel, comme I'Organum de Bacon et le Discours de la Methode de Descartes,' while Professor Noire, with his wider sympathies for every sphere of intel- lectual activity, counts six books, in the literature of modern Europe, as the peers of Kant's Critique, viz. Copernicus, De revolutionibus orbium coelestium (1543) ; Descartes, Meditationes de prima philosophia ' Commentar zu Kant's Kritik der reinen Venmnft, zum hun- dertjahrigen Jubilaum derselben, herausgegeben von Dr. H. Vai- hinger. Stuttgart, 1 88 1. ^ Zum Jubilaum von Kant's Kritik der reinen Vernuuft, von H. Vaihinger, Separatabdruck aus der Wochenschrift, ' Im neuen Eeich,' i88i, No. 23, p. 14. ^ Kevue des deux Mondes, 1879, Aout. xliv translatok's preface. (1641); Newton, Principia philosopliiaj naturalis ma- thematica (1687); Montesquieu, Esprit des Lois ( 1 748) ; Winckelmann, Geschiclite der Kunst des Alter- thums (1764) i and Adam Smith, Inquiry into the nature and causes of the Wealth of Nations (i 776),— but he places Kant's Critique at the head of them all. I confess I feel almost ashamed lest it should be supposed that I thought Kant in need of these testimonies. Mj only excuse is that I had to defend myself against the suspicion of having wasted my time, and I therefore thought that by pointing out the position assigned to Kant's Critique among the master-works of human genius by men of greater weight than I could ever venture to claim for myself, I might best answer the kindly meant question ad- dressed to me by my manj^ friends : ' But how can you waste your time on a translation of Kant's Critik der rein en VernunftV On the Text of Kant's Critique of Pure Reason. I have still to say a few words on the German text on which my translation is founded. I have chosen the text of the First Edition, first of all, because it was the centenary of that edition which led me to carry out at last my long- cherished idea of an English translation. That text represents an historical event. It represents the state of philosophy, as it was then, it represents Kant's mind as it was then, at the moment of the greatest crisis in the history of philosophy. Even if the later editions con- tained improvements, these improvements would belong to a later phase in Kant's own development. translator's preface. xlv and it is this first decisive position, as taken by Kant against both Hume and Berkeley, that more than anything else, deserves to be preserved in the history of philosophy. Secondly, I must confess that I have always used myself the First Edition of Kant's Critique, and that when I came to read the Second Edition, I never could feel so at home in it as in the first. The First Edition seems to me cut out of one block, the second always leaves on my mind the impression of patchwork. Thirdly, I certainly dislike in the Second Edition a certain apologetic tone, quite unworthy of Kant. He had evidently been attacked by the old Wolfian professors, and also by the orthodox clergy. He knew that these attacks were groundless, and arose in fact from an imperfect understanding of his work on the part of his critics. He need not have con- descended to show that he was as well-schooled a philosopher as any of his learned colleagues, or that his philosophy would reaUy prove extremely useful to orthodox clergymen in their controversies with sceptics and unbelievers. So far, and so far only, can I understand the feel- ing against the Second Edition, which is shared by some of the most accurate and earnest students of Kant. But I have never been able to understand the ex- aggerated charges which Schopenhauer and others bring against Kant, both for the omissions and the additions in that Second Edition. What I can under- stand and fully agree with is Jacobi's opinion, when xlvi translator's preface. lie says ^ : ' I consider the loss which the Second Edition of Kant's Critique suffered by omissions and changes very considerable, and I am very anxious by the expression of my opinion to induce readers, who seriously care for philosophy and its history, to com- pare the first edition of the Critique of Pure Keason with the second improved edition. ... It is not suffi- ciently recognised what an advantage it is to study the systems of great thinkers in their first original form. I was told by Hamann that the very judicious Ch. J. Krause (or Kraus) could never sufficiently ex- press his gratitude for having been made acquainted with Hume's first philosophical work. Treatise on Human Nature, 1 739, where alone he had found the right point of view for judging the later essays.' Nor do I differ much from Michelet, in his History of the later systems of Philosophy in Germany (1837, vol. i. p. 49), where he says, ' Much that is of a more speculative character in the representation of Kant's system has been taken from the First Edition. It can no longer be found in the second and later editions, which, as well as the Prolegomena, keep the idealistic tendency more in the background, because Kant saw that this side of his philosophy had lent itself most to attacks and misunderstandings.' I can also understand Schopenhauer, when he states that many things that struck him as obscure and self- contradictory in Kant's Critique ceased to be so when he came to read that work in its first original form. But everything else that Schopenhauer writes on the difference between the first and second editions of the ' Jacobi's Works, vol. ii. p. 291 (1815). translator's preface. xlvii Critique seems to me perfectly intolerable. Kant, in the Preface to his Second Edition, which was pub- lished six years after the first, in 1 78 7, gives a clear and straightforward account of the changes which he introduced. ' My new representation,' he writes, ' changes absolutely nothing with regard to my pro- positions and even the arguments in their support.' He had nothing to retract, but he thought he had certain things to add, and he evidently hoped he could render some points of his system better under- stood. His freedom of thought, his boldness of speech, and his love of truth are, if I am any judge in these matters, the same in 1787 as in 1781. The active reactionary measiires of the Prussian Government, by which Kant is supposed to have been frightened, date from a later period. Zedlitz, Kant's friend and pro- tector, was not replaced by Wollner as minister till 1788. It was not till 1794 that Kant was really warned and reprimanded by the Cabinet, and we must not judge too harshly of the old philosopher when at his time of life, and in the then state of paternal despotism in Prussia, he wrote back to say 'that he would do even more than was demanded of him, and abstain in future from all public lec- tures concerning religion, whether natural or re- vealed.' What he at that time felt in his heart of hearts we know from some remarks found after his death among his papers. 'It is dishonourable,' he writes, ' to retract or deny one's real convictions, but silence, in a case like my own, is the duty of a subject ; and though all we say must be true, it is not our duty to declare publicly all that is true.' xlviii translatok's pkeface. Kant never retracted, lie never even declared himself no longer responsible for any one of those portions of the Critique which he omitted in the Second Edition. On the contrary, he asked his readers to look for them in the First Edition, and only ex- pressed a regret that there was no longer room for them in the Second Edition. Now let us hear what Schopenliauer says. He not only calls the Second Edition ' crippled, dis- figured, and corrupt,' but imputes motives utterly at variance with all we know of the truthful, manly, and noble character of Kant. Schopenhauer writes : ' What induced Kant to make these changes was fear of man, produced by weakness of old age, which not only affects the head, but sometimes deprives the heart also of that firmness which alone enables us to despise the opinions and motives of our contempora- ries, as they deserve to be. No one can be great without that.' All this is simply abominable. First of aU, as a matter of fact, Kant, when he pubhshed his Second Edition, had not yet collapsed under the weak- ness of old age. He was about sixty years of age, and that age, so far from making cowards of us, gives to most men greater independence and greater boldness than can be expected from the young, who are awed by the authority of their seniors, and have often to steer their course prudently tlirough the conflicts of parties and opinions ^. What is the use of grow- ^ ' En g6ii(5ral la vigueur de I'esprit, soit dans la politique, soit dans la science, ne se deploie dans toute sa pMnitude qua Tags oh I'activite vitale vient a s'affaiblir.' E. Saisset, L'Ame et la Vie, p. 60. translator's preface. xlix ing old, if not to gain greater confidence in our opinions, and to feel justified in expressing them with perfect freedom "? And as to ' that firmness which alone enables us to despise the opinions and motives of our contemporaries,' let us hope that that is neither a blessing of youth nor of old age. Schopenhauer personally, no doubt, had a right to complain of his contemporaries, but he would have been greater if he had despised them either less or more, or, at all events, if he had despised them in silence. I am really reluctant to translate aU that follows, and yet, as Schopenhauer's view has found so many echoes, it seems necessary to let him have his say. ' Kant had been told,' he continues, 'that his system was only a rechauffe of Berkeley's Idealism. This seemed to him to endanger that invaluable and indispensable originality which every founder of a system values so highly (see Prolegomena zu jeder ktinftigen Metaphysik, pp. 70, 202 sq.). At the same time he had given offence in other quarters by his upsetting of some of the sacred doctrines of the old dogmas, particularly of those of rational psycho- logy. Add to this that the great king, the friend of light and protector of truth, had just died (1786). Kant allowed himself to be intimidated by aU this, and had the weakness to do what was unworthy of him. This consists in his having entirely changed the first chapter of the Second Book of the Tran- scendental Dialectic (first ed., p. 341), leaving out fifty-seven pages, which contained what was in- dispensable for a clear understanding of the whole work, and by the omission of which, as well as by VOL. I. d 1 translator's preface. what he put in its place, his whole doctrine becomes full of contradictions. These I pointed out in my critique of Kant (pp. 612-18), because at that time (in 18 1 8) I had never seen the First Edition, in which they are really not contradictions, but agree perfectly with the rest of his work. In truth the Second Edition is like a man who has had one leg amputated, and replaced by a wooden one. In the preface to the Second Edition (p. xlii), Kant gives hollow, nay, untrue excuses for the elimination of that important and extremely beautiful part of his book. He does not confessedly wish that what was omitted should be thought to have been re- tracted by him. " People might read it in the First Edition," he says ; " he had wanted room for new additions, and nothing had been changed and im- proved except the representation of his system." But the dishonesty of this plea becomes clear if we com- pare the Second with the First Edition. There, in the Second Edition, he has not only left out that important and beautiful chapter, and inserted under the same title another half as long and much less significant, but he has actually embodied in that Second Edition a refutation of idealism which says the very contrary of what had been said in the omitted chapter, and defends the very errors which before he had thoroughly refuted, thus contradicting the whole of his own doctrine. This refutation of ideahsm is so thoroughly bad, such palpable sophistry, nay, in part, such a confused " galimatias,'' that it is unworthy of a place in his immortal work. Conscious evidently of its insufficiency, Kant has tried to im- translatoe's preface. li prove it by the alteration of one passage (see Preface, p. xxxix) and by a long and confused note. But he forgot to cancel at the same time in tlie Second Edition the numerous passages which are in contradiction with the new note, and in agreement with what he had cancelled. This applies particularly to the whole of the sixth section of the Antinomy of Pure Reason, and to all those passages which I pointed out with some amazement in my critique (which was written before I knew the First Edition and its later fate), because in them he contradicts himself. That it was fear which drove the old man to disfigure his Critique of rational psychology is shown also by this, that his attacks on the sacred doctrines of the old dogmatism are far weaker, far more timid and superficial than in the First Edition, and that, for the sake of peace, he mixed them up at once with anticipations which are out of place, nay, cannot as yet be understood, of the immortahty of the soul, grounded on practical reason and represented as one of its postulates. By thus timidly yielding he has in reality retracted, with regard to the principal problem of all philo- sophy, viz. the relation of the ideal to the real, those thoughts which he had conceived in the vigour of his manhood and cherished through all his life. This he did in his sixty-fourth year with a carelessness, which is peculiar to old age quite as much as timidity, and he thus surrendered his system, not however openly, but escaping from it through a back-door, evidently ashamed himself of what he was doing. By this process the Critique of Pure Eeason has, in its Second Edition, become a self- d 2 lii translator's preface. contradictory, crippled, and corrupt book, and is po longer genuine.' ' The wrong interpretation of the Critique of Pure Eeason, for which the successors of Kant, both those who were for and those who were against him, have blamed each other, as it would seem, with good reason, are principally due to the so-called improve- ments, introduced into his work by Kant's own hand. For who can understand what contradicts itself T The best answer to all this is to be found in Kant's own straightforward statements in the Preface to his Second Edition (Supplement IT. pp. 364 seqq.). That the unity of thought which pervades the First Edition is broken now and then in the Second Edition, no attentive reader can fail to see. That Kant shows rather too much anxiety to prove the harmlessness of his Critique, is equally true, and it would have been better if, while refuting what he calls Empirical Ideahsm, he had declared more strongly his unchanged adherence to the principles of Tran- scendental Idealism^. But all this leaves Kant's moral character quite untouched. If ever man lived the hfe of a true philosopher, making the smallest possible concessions to the inevitable vanities of the world, valuing even the shadowy hope of posthumous fame ^ at no more than its proper worth, but fully enjoying the true enjoyments of this life, an un- swerving devotion to truth, a consciousness of righteousness, and a sense of perfect independence, that man was Kant. If it is true that on some ' See Critique, p. 320 (369). ^ See Critique of Pure Keason, Supp. XXVII. p. 508. translator's preface. liii points which may seem more important to others than they seemed to himself, he changed his mind, or, as we should now say, if there was a later development in his philosophical views, this would seem to me simply to impose on every student the duty, which I have tried to fulfil as a translator also, viz. first of all, to gain a clear view of Kant's system from his First Edition, and then to learn, both from the additions and from the omissions of the Second Edition, on what points Kant thought that the objections raised against his theory required a fuller and clearer statement of his arguments. The additions of the Second Edition will be found on pp. 361-512, of the first volume, whde the passages omitted in the Second Edition have been included throughout between parentheses. Critical Treatment of the Text of Kant's Critique. The text of Kant's Critique has of late years be- come the subject of the most minute philological criticism, and it certainly offers as good a field for the exercise of critical scholarship as any of the Greek and Eoman classics. We have, first of all, the text of the First Edition, full of faults, arising partly from the imperfect state of Kant's manuscript, partly from the carelessness of the printer. Kant received no proof-sheets, and he examined the first thirty clean sheets, which were in his hands when he wrote the preface, so carelessly that he could detect in them only one essential misprint. Then followed the Second, ' here and there liv translator's preface. improved; Edition (1787), in which Kant not only omitted and added considerable passages, but paid some little attention also to the correctness of the text, improving the spelling and the stopping, and removing a number of archaisms which often perplex the reader of the First Edition. "We hardly know whether these minor alterations came from Kant himself, for he is said to have been firmly attached to the old system of orthography ^ ; and it seems quite certain that he himself paid no further attention to the later editions, published during his lifetime, the Third Edition in 1 790, the Fourth in 1 794, the Fifth in 1 799. At the end of the Fifth Edition of the Critique of Pure Reason, published in 1 799, there is a long list of Corrigenda, the authorship of which has exercised the critical students of Kant's text very much. No one seems to have thought of attributing it to Kant him- self, who at that time of life was quite incapable of such work. Professor B. Erdmann supposed it might be the work of Eink, or some other amanuensis of Kant. Dr. Vaihinger has shown that it is the work of a Professor Grille, who, in the FliUosoj)liisclie Anzeiger, a Supplement to L. H. Jacob's" Anna- len cler FliilosopMe und des philoso^Jiischen Geistes, I 795, published a collection of Corrigenda, not only for Kant's Critique of Pure Eeason, but for several other of his works also. Another contributor to the same journal, Meyer, thereupon defended Kant's publisher (Hartknoch) against the charges of carelessness, re- jected some of Grillo's corrections, and showed that ' See Kehrbach, Kritik der reineu Vernunft, p. viii. translator's preface. Iv what seemed to be misprints were in many cases peculiarities of Kant's style. It is this list of Professor Grillo which, with certain deductions, has been added to the Fifth Edition of the Critique. Some of Grillo's corrections have been adopted in the text, while others, even those which Meyer had proved to be unnecessary, have retained their place in the list. With such materials before him, it is clear that a critical student of Kant's text enjoys considerable freedom in conjectural emendation, and that free- dom has been used with great success by a number of German critics. The more important are : — Rosenkranz, in his edition of Kant's Critique (text of First Edition), 1838. Hartenstein, in his edition of Kant's Critique (text of Second Edition), 1838, 1867. Kehrbach, in his edition of Kant's Critique (text of First Edition), 1877. Leclair, A. von, Kritische Beitrage zur Kategorien- lehre Kant's, 1871. Paulsen, Versuch einer Entwickelungsgeschichte der Kantischen Erkenntnisslehre, 1875. Erdmann, B., Kritik der reuien Vernunft (text of Second Edition), 1878, with a valuable chapter on the Eevision of the Text. Many of the alterations introduced by these critics affect the wording only of Kant's Critique, without materially altering the meaning, and were therefore of no importance in an English translation. It often happens, however, that the construction of a whole sentence depends on a very shght alteration of the text. In Kant's long sentences, the gender of the Ivi tkanslator's preface. pronouns der, die, das, are often our only guide in discovering to what substantive these pronouns refer, while in English, where the distinction of gender is wanting in substantives, it is often absolutely necessary to repeat the substantives to which the pro- nouns refer. But Kant uses several nouns in a gender which has become obsolete. Thus he speaks ^ of der Wachsthum, der Wolilgef alien, der Gegentheil, die Hin- derniss, die Bediirfniss, die Verhdltniss, and he varies even between die and das Verhciliniss, die and das Erhenntniss, etc., so that even the genders of pro- nouns may become bhnd guides. The same applies to several prepositions which Kant construes with different cases from what would be sanctioned by modern German grammar 2. Thus ausser with him governs the accusative, wahrend the dative, etc. For all this, and many other peculiarities, we must be prepared, if we want to construe Kant's text correctly, or find out how far we are justified in altering it. Much has been achieved in this line, and con- jectural alterations have been made by recent editors of Kant of which a Bentley or a Lachmann need not be ashamed. In cases where these emenda- tions affected the meaning, and when the reasons why my translation deviated so much from the textus rece^ptus might not be easily perceived, I have added the emendations adopted by me, in a note. Those who wish for fuller information on these points, will have to consult Dr. Vaihinger's forthcoming Com- mentary, which, to judge from a few specimens kindly ' See Erdmann, p. 637. ^ ggg Erdmann, p. 660. translator's preface. Ivii communicated to me by the author, will give the fullest iaformation on the subject. How important some of the emendations are which have to be taken into account before an intelhgible translation is possible, may be seen from a few specimens. On p. 382 (442) the reading of the first edition Antithesis must be changed into Tliesis. Page 470 (545), Noumenon seems preferable to Phssnomenon. Page 420 (484), we must read keine, instead of eine WahrneJimung. Page 295 (340), we must keep the reading of the First Edition transcendentalen, instead of transcen- denten, as printed in the Second ; while on p. 578 (674), transcendenten may be retained, though cor- rected into transcendentalen in the Corrigenda of the Fifth Edition. On p. 670 (781), the First Edition reads, sind also Jceine Frivatmeinungen. Hartenstein rightly corrects this into reine Frivatmeinungen, i. e. they are mere private opinions. Page 714 (832), instead of ein jeder Theil, it is proposed to read Icein Theil. This would be neces- sary if we took vermisst werden Tcann, in the sense of can he sjpared, while if we take it in the sense of can he missed, i. e. can be felt to be absent, the reading of the First Edition ein jeder Theil must stand. See the Preface to the First Edition, p. xx, note i . On p. (138) 157, the First Edition reads, Weil sie kein Drittes, niimlich reinen Gegenstand haben. This gives no sense, because Kant never speaks of a Iviii teanslatok's preface. reinen Gegenstand. In tlie list of Corrigenda at the end of the Fifth Edition, reinen is changed into leinen, which Hartenstein has rightly adopted, while Eosenkranz retains reinen. On pp. 16 and 17 of the Introduction to the Second Edition (Supplement VI. p. 407). Dr. Vaihinger has clearly proved, I think, that the whole passage from Einige ivenige Grundsatze to Eonnen dar- gesteUt iverden interrupts the drift of Kant's argu- ment. It probably was a marginal note, made by Kant himself, but inserted in the wrong place. It would do very well as a note to the sentence : Elen so wenig ist irgend ein Grundsatz der reinen Geometrie analytiscJi. With these prefatory remarks I leave my trans- lation in the hands of English readers. It contains the result of hard work and hard thought, and I trust it will do some good. I have called Kant's philosophy the Lingua Franca of modern philosophy, and so it is, and I hope will become so still more. But that Lingua Franca, though it may contain many familiar words from all languages of the world, has yet, like every other language, to be learnt. To expect that we can understand Kant's Critique by simply reading it, would be the same as to attempt to read a French novel by the light of English and Latin. A book which Schiller and Schopenhauer had to read again and again before they coiild master it, will not yield its secrets at the fiist time of asking. An Indian proverb says that it is not always the fault of the post, if a blind man cannot see it, nor is it always the teanslator's preface. lix fault of the profound thinker, if his language is unin- telligible to the busy crowd. I am no defender of dark sayings, and I still hold to an opinion for which I have often been blamed, that there is nothing in any science that cannot be stated clearly, if only we know it clearly. Still there are limits. No man has a right to complain that he cannot understand higher mathematics, if he declines to advance step by step from the lowest to the highest stage of that science. It is the same in philosophy. Philosophy represents a long toil in thought and word, and it is but natural that those who have toiled long in inward thought should use certain concepts, and bundles of concepts, with their algebraic exponents, in a way entirely be- wildering to the outer world. Kant's obscurity is owing partly to his writing for himself rather than for others, and partly to his addressing himself, when defending a cause, to the judge, and not to the jury. He does not wish to persuade, he tries to convince. No doubt there are arguments in Kant's Critique which fail to convince, and which have pro- voked the cavils and strictures of his opponents. Kant would not have been the really great man he was, if he had escaped the merciless criticism of his smaller contemporaries. Btit herein too we perceive the greatness of Kant, that those hostile criticisms, even where they are well founded, touch only on less essential points, and leave the solidity of the whole structure of his philosophy unimpaired. No first perusal will teach us how much of Kant's Critique may safely be put aside as problematical, or, at all events, as not essential. But with every year, and Ix translator's preface. with every new perusal, some of these mists and clouds seem to vanish, and the central truth is seen rising before our eyes with constantly increasing warmth and splendour, hke a cloudless sun in an Eastern sky. And now, while I am looking at the last lines that I have written, it may be the last Hues that I shall ever write on Kant, thp same feeling comes over me which I expressed in the Preface to the last volume of my edition of the Eig-Yeda and its ancient com- mentary. I feel as if an old friend, with whom I have had many communings during the sunny and during the dark days of life, was taken from me, and I should hear his voice no more. The two friends, the Rig- Veda and Kant's Critique of Pure Eeason, may seem very different, and yet my life would have been incomplete without the one as without the other. The bridge of thoughts and sighs that spans the whole history of the Aryan world has its first arch in the Veda, its last in Kant's Critique. In the Veda we watch the first unfolding of the human mind as we can watch it nowhere else. Life seems simple, natural, childfike, full of hopes, undisturbed as yet by many doubts or fears. What is beneath, and above, and beyond this life is dimly perceived, and expressed m a thousand words and ways, all mere stammerings, all aiming to express what cannot be expressed, yet all full of a belief in the real pre- sence of the Divine in Nature, of the Infinite in the Finite. Here is the childhood of our race unfolded before our eyes, at least so much of it as we shall teanslatoe's preface. , Ixi ever know on Aryan ground, — and there are lessons to be read in those hymns, ay, in every word that is used by those ancient poets, which will occupy and delight generations to come. And while in the Veda we may study the child- hood, we may study in Kant's Critique of Pure Reason the perfect manhood of the Aryan mind. It has passed through many phases, and every one of them had its purpose, and has left its mark. It is no longer dogmatical, it is no longer sceptical, least of all is it positive. It has arrived at and passed through its critical phase, and in Kant's Critique stands before us, conscious both of its weakness and of its strength, modest, yet brave. It knows what the old idols of its childhood and of its youth too were made of It does not break them, it only tries to understand them, but it places above them the Ideals of Reason — no longer tangible — not even within reach of the understanding — yet real, if any- thing can be called real, — bright and heavenly stars to guide us even in the darkest night. In the Veda we see how the Divine appears in the fire, and in. the earthquake, and in the great and strong wind which rends the mountain. In Kant's Critique the Divine is heard in the still small voice — the Categorical Imperative — the I Ought — which Nature does not know and cannot teach. Every- thing in Nature is or is not, is necessary or contingent, true or false. But there is no room in Nature for the Ought, as little as there is in Logic, Mathematics, or Geometry. Let that sufBce, and let future generations learn all the lessons contained Ixii translator's preface. in that simple word, I ought, as interpreted by Kant. I feel I have done but little for my two friends, far less than they have done for me. I myself have learnt from the Veda all that I cared to learn, but the right and full interpretation of all that the poets of the Vedic hymns have said or have meant to say, must be left to the future. What I could do in this short life of ours was to rescue from oblivion the most ancient heirloom of the Aryan family, to establish its text on a sound basis, and to render accessible its venerable Commentary, which, so long as Vedic studies last, may be criticised, but can never be ignored. The same with Kant's Critique of Pure Eeason. I do not venture to give the right and full explana- tion of all that Kant has said or has meant to say. I myself have learnt from him all that I cared to learn, and I now give to the world the text of his principal work, critically restored, and so translated that the translation itself may serve as an explana- tion, and in some places even as a commentary of the original. The materials are now accessible, and the English-speaking race, the race of the future, will have in Kant's Critique another Aryan heirloom, as precious as the Veda — a work that may be criticised, but can never be ignored. F. MAX MtJLLER. OXFOED, November 25, 1881. THE CRITIQUE OF PUEE EEASON AS ILLUSTRATED BY A SKETCH OF THE DEVELOPMENT OF OCCIDENTAL PHILOSOPHY LUDwiG Nomi:. INTRODUCTION. ' The history of philosophy has ceased,' says Las- salle 1, ' to count as a mere collection of curiosities, an assemblage of arbitrary or accidental opinions. Thought too is seen to be an historical product ; and the history of philosophy a representation of the course of its self-development in necessary con- tinuity. And if the history of philosophy, hke all other historical development, is governed by inner necessary laws, then surely, here if anywhere, in this history of knowledge, the law of the development of knowledge must coincide with the law of knowledge itself.' I have taken these words as the motto of the following historical introduction, although they are not free from the obscurity and confusion of thought which flourished under the rule of Hegelianism. For the 'History of Philosophy' and the 'History of Knowledge ' are very far from being identical. If our conception of philosophy includes all those reflections which the human mind has at different times in- dulged in respecting its own nature, then the history of philosophy will be a history of these reflections, and will form only a portion, though an important one, of the ' History of Knowledge,' and this only so far as it satisfies the true test of value by exercising ^ Die PbiloEophie Herakleitos des Dunkeln, i. p. xii. VOL. I. B 2 INTRODUCTION. a lasting influence upon the processes of human thought. It is however possible to regard the history of knowledge as the chief or sole object of philosophical research, and if such a view has not yet received the adherence of the majority, it has at least been formulated by one authority of weight, in these terms : 'All future 'philosoinliy must he a philoso- jjhy of language.' Notwithstanding this obvious confusion of terms, I have chosen the above words of Lassalle as a motto for the present work, first, because of the great truth which they do contain, and, secondly, because of their appropriateness at the present day, when, more than at any previous time, the conviction is gaining ground that in order to understand any fact or phe- nomenon, any manifestation of human opinion, feel- ing or belief, we must first familiarise ourselves with its origin and its past development. And I may hojoe that the two great camps in which the men of science and the philosophers — the empiricists and a-priorists — are drawn up will be reconciled and meet here as upon neutral ground. For the former, the motto promises a discussion of development, and of development according to natural, impartial reason- ing : while to the latter it concedes the lofty, mar- vellous and incomprehensible faculty distinguishing mankind, — reason, — towards which no Darwinian has as yet succeeded in the least degree in estabhshing a bridge from out the animal worlds Kant's Critik der Beinen Vernunft represents the greatest revolution which has ever taken place in ' Instead of this, human reason has been imported into the animal world, and the problem, so far from being cleared up, has thus been rendered doubly obscure, as, for instance, by Sir J. Lubbock in his observations on ants. INTRODUCTION. 3 the realms of speculation. It has often been com- pared, and among others by the author himself, with the Copernican system. Not less truly it has been likened by Rosenkranz to the head of Janus in the temple of philosophy, concentrating in itself all the conquests of preceding labours, while all further pro- gress has to take its departure thence. To do full justice to its significance requires therefore a retro- spective survey of all that has been done in this region from the first existence of philosophy. Philosophy begins when men first begin to reflect with curiosity about themselves and the world around them ; it begins therefore when primitive religion, which appears as the earliest and most natui'al interpretation of the universe, is no longer able to satisfy them with the imaginative language of mythology. They do not guess that it is their own reason which drives them to seek for new ex- planations ; the double problem of world and mind still appears as a simple one, and they seek to attain the desired explanation from the world and m the world. An organic presentation of the history of philoso- phy would therefore have to show how reason first takes the widest flights in search of its proper object, which go on narrowing in the course of cen- turies till at last they only embrace a narrow spot within which the self and its own nature appears to the astonished gaze as the true Archimedean point whence everything else is to be explained. In the following pages I have endeavoured to trace in broad outline the course which has been pursued from the earliest beginnings to this goal. In order to carry out the programme laid down I have traced the organic structure of this development B 2 INTRODUCTION, to a single idea as simple as the nature of know- ledge itself. It is to be hoped that this sim- plicity will not prove a stumbling-block. The grounds upon which it rests will not become ap- parent till we reach the beginning of the sketch of medifeval philosophy. For the present it is suffi- cient to observe in reference to the ideal of pure reason set up by Kant that the essence of the ancient philosophy was cosmology, that of the mediaeval, theology, and that of the modern, ])sychology. I say the essence, meaning only the great currents of thought, which had received a decisive direction towards a certain quarter, in each principal epoch of development, notwithstanding the apparently oppo- site bent of minor tributaries, of isolated thoughts and opinions whose true value and significance can only be estimated at a later date when a new theory of the universe has been accepted. However high the summit of a tree may reach, its root is in the soil beneath, and philosophers too are children of their age and can never wholly free themselves from the ideas, convictions, and prejudices which surround them : their thoughts are borne along with the torrent of the general thought. Yet it is an interesting spectacle to watch the truths and theories of a future day germinating in earlier times as on a foreign soil. And of this we need only say that there is no tendency of modern thought which has not its prototype in Greek philo- sophy, none except that which must be called the modern tendency /car' e^yx^" — the Ego of Descartes. At the same time it must be obvious to every thoughtful mind that it is just this latest develop- ment which has made all the ancient systems and forecasts to appear in a new hght, so that even when INTRODUCTION. 5 the original hne of the stream remains to testify to its origin, still in the new current with which it mingles, it struggles onwards under quite different conditions and in a fresh direction. The doctrines of Kant may be recognised, as we shall see, in the views of Herakleitos and Protagoras, but in a form which bears the same relation to his work as the guesses of the Pythagoreans about the earth's motion do to the calculations of Copernicus, Galileo, and Newton. Kant himself seems to have foreseen the chance of such insinuations, for he appeals to those who take the ' History of Philosophy ' for phi- losophy itself, 'to wait till his investigations have become historical, after which it would be their turn to instruct the world as to what had happened be- fore. Otherwise nothing could ever be said which had not, in their opinion, been said already, and in- deed this saying itself may be a trustworthy pro- phecy of what is to be said hereafter. For, since the human understanding has occupied itself for many centuries with countless objects in various ways, it would be almost strange if something old could not be found to resemble every novelty \' Schopenhauer's answer to those who, after ignoring his work for a generation, professed to find it fore- stalled in a sentence of Schelling (' Wollen ist Ursein'), is to the purpose here : 'He only, who has discerned the reasons and thought out the conse- quences of a truth, who has developed its whole content and surveyed its whole scope, and who has then with full consciousness of its worth and weightiness given clear and coherent expression to it, he and he onlv is its author and oririnator^' ^ Prolegomena, Preface. ^ Parerga utid Paralipomena, i. 144. 6 INTRODUCTION. Kant then, who analysed the human reason into its ultimate elements and so first made it fully in- telligible to itself, marks the close of a period of development, which now lies spread out as a whole before our eyes, and which we have to trace through its origin and its progress, its uncei'tain steps and tentative searchings, its confident struggles and its anxious doubts, its apparent retrogression and its gallant onward strides. The palm of valour belongs to the hero of thought who has plunged into the obscurest abysses of the human mind and, with almost superhuman calm, has succeeded in emerging with the key to the mystery in his hand. In Kant, in the truest sense of the words, reason has come to herself. He has made an end for ever of all mystical admixtures, all un- justifiable pretensions, all Icarus-like flights towards forbidden regions. If, as no one has yet questioned, reason is the true and only tool and means to which man owes his high place, his successes and his inward nobility, Kant must be recognised mth equal un- reserve as the greatest benefactor of humanity. May the seed which he has scattered ripen everywhere ; may the light of day which rose with him spread over every region of thought and conduct ; and above all, may the broils, at once so empty and embittered, and the logomachies of the school which have already done so much to damage philosophy in the estima- tion of some of the good and wise, may these at length be silenced, and the name of Kant become a rallying-point of union for all genuine and honest lovers of truth in every science and among every nation. This is the only worthy return which our gratitude to this great thinker can bring to celebrate the jubilee of his immortal work. INTRODUCTION. 7 Perikles said that ' the whole world is the tomb of the great,' and we may say of Kant, Time and Space cannot limit the action of great men. Of him, more than of any child of man, the poet's words are true — ' Es kann die Spur von meinen Erdentageii Nieht in ^onen untergehn.' ANCIENT PHILOSOPni. ^Ef avrl TTavTcoi'.- — ' Ovrois ov. The character of ancient pliilosoiihy is naively objective. Antiquity knew nothing of the im^jortant distinction, introduced by Descartes, between the thinking subject and the object of thought, which is now recognised as the necessary starting-point of all philosophical enquiry. What we think and have to think, was still the chief matter: the question lioiv we think had not yet presented itself. Even the highest achievement of ancient philosophy, the Platonic Idealism, did not escape these fetters of objectivity; the rational soul was conceived to be capable of discerning ideas in their purity and clear- ness, but objective reality was attributed to the ideas. Philosophical questions in antiquity vs^ere accord- ingly ontological ; in other words, Being was everv- ^^■here presupposed and further investigation was directed only towards the nature of being, and how many kinds there were of being, whether one or many. While we have been in the habit, since Des- cartes, of starting from the knowing subject, and, since Kant, of deducing thence the conception of being, such an idea seldom presented itself to the ancients ; they could only explain the nature of reason by assuming the mind to be a real entity. ANCIENT PHILOSOPHY. 9 and then enquire further whether it was a special kind of being, or Avhether it was identical with matter ; whether it was a kind of sensibility, or whether it was a part of the general world-soul. The true path of ideahsm was still undiscovered. Reason, however, in obedience to its natural bent, was .striving everywhere towards unity, little sus- pecting in its search after unity that the true source thereof lay in itself, and that all the while it was but projectii:ig its own nature outwards into the world of Being. It may be said then of the philosophy of the an- cients that it consisted of attempts to explain the world by means of a single principle which was ex- pected to furnish an explanation of reason and the human soul. This is the natural course of the de- velopment and progress of knowledge ; the last thing that man discovers is his own Ego ; the outer world is always the most certain and the most original in his eyes. In this sense Sokrates observes in the Phaedros : ' Do you then believe that one may understand the nature of the soul without discern- ment of nature as a whole V The childish beginnings of philosophy among the Greeks therefore all take the form of naturalism. The principles or causes of the universe were sought in water, air, the sether or fire. The material thrust itself in among what was formal and peculiar to the mind, and little blame can be imputed to the ancients for this ; seeing how many there are at the present day who cannot emancipate themselves from this objective pressure, and persist in raising such ques- tions as whether the soul is material, which is about as rational as to ask if a circle is quadrangular or if a mathematical triangle is green or blue. lO ANCIENT PHILOSOPHY. The first attempt to place the One at the summit of a theory of the universe was made by the Eleatics. They were inspired by the dim consciousness that rational knowledge is impelled to strive after com- pleteness, duration, and unchangeableness. The op- position or incompatibility between this desired unity and the manifold variety in the outer world called for some compromise of conciliation, and hence we find first in the Eleatic school the opposition between per- ception and thought, between the Phenomenon and the Noumenon. The latter alone is the really existing, it is unchangeable, immoveable, ever resting ; the world of sense, on the contrary, is vacillating, deceptive, ever in motion. The appearances of sensibility, or pheno- mena, must therefore be reconciled or corrected by the really Existing which can only be conceived in thought. But the confusion between the real and the ideal is very strikingly apparent here when we find the greatest master of this school, the univer- sally revered Parmenides, asserting that ' Being and Thought are one and the same.' What may pass for lofty wisdom in those early days of the laborious struggles of the reason towards self-know- ledge, must be condemned as dull absurdity when it appears after Kant and Descartes in the Hegelian Dialectic. The direct opposite to the Eleatic school is found in Herakleitos ; in the former we Avelcome the first glimpses of the idea of substance, of the principle of the indestructibility of force, as well as of the sub- sequent investigations of Greulinx and Locke re- specting the difference between real or primary and sensibly perceptible quahties, or between the intuitions of sense and reason ; we see too the first conscious- ness of the antinomies which led to the immortal ANCIENT PHILOSOPHY. II achievements of Kant\ Herakleitos too was seeking for a secure and durable principle that should be applicable everywhere and always, and only need to be expressed to furnish the key to the nature of the world. He finds this durable and eternal principle, not like the Eleatics in rest, but, on the contrary, in strife, incessant flux and change. The true Being is an eternal Becoming, a state between being and not being. His famous saying of the universal flux of things rests upon the self-evident aptness of the description of a stream to which he appeals, show- ing it to be impossible to step twice into the same stream, seeing that the water composing it is always diflferent. The latest conclusion which was to be deduced from this fruitful idea is that the nature of substance must remain eternally unknowable by us, as it will always be impossible to distinguish whether the phenomenon before us proceeds from the identical same atoms as before or whether others have taken their place. Our reason is in any case compelled to picture matter as the persistent element, but this same matter remains for ever incomprehensible to us. For the rest, the positive side of this profound thinker's suggestion is from many points of view ' Zeno, the Eleatic, whom Aristotle called the father of dialectic, was the first to prove that multiplicity and motion were impossible; the former because the many must be a particular number over and above which there might be always one more, the latter because of the well-known property of time and space by which they admit of infinite division. The arrow in its flight is always in 07ie in- finitely minute portion of space, — it is therefore always at rest. A definite time cannot elapse, a definite space be traversed, because first the half, and then the half of the half, and so on ad infinitum, has to elapse or be passed through, which gives an endless series of subdivisions. 12 ANCIENT PHILOSOPHY, still clear and intelligible. The change of matter which goes on in organic structures, the circulation of life, the principle of substitution S these all point towards that original idea as to their germ. There can be no doubt that Herakleitos himself fully com- prehended the significance of his own thought, as the key to the knowledge of the world and life. This appears especially from the fact that he saw in motion, in restless activity and change, the real principle of life. This is clear from a passage that runs, 'Herakleitos banished rest and stability from the world ; for these are the qualities of corpses ^Z In reference to rational knowledge or percep- tion, it is in the highest degree interesting to find that Herakleitos had a presentiment of its being constituted by means of two factors. At least, it is reported by Sextus Empiricus^, that according to Herakleitos, the soul attains to rational thought by receiving into itself the divine Logos which presides over the outer world ; that in sleep this connection with the outer world ceases, and when so separated the soul loses the power of recollection. On waking ' An importfint application of this principle, with obvious re- ference to Herakleitos, occurs in Aristotle (Polit. iii, c. 3), who says, that we call a city the same as long as one and the same race inhabits it, although there are always some dying and others being born, as we are accustomed to call rivers and springs the same, although in the one case water is always pouring in and in the other flowing away. And the remark is transferred by Seneca to the human organism (Ep. Iviii) : ' No one is the same as an old man that he was as a youth, no one is to-day what he was yester- day. Our bodies change as streams do, and everything flows away as time does ; nothing endures. This was the opinion of Hera- kleitos, — the name of the stream remains, the water runs away. This is clearer in all other things than in the case of man but we too are borne along in equally rapid course." 2 Plut. Plac. Phil. i. 23. = Adv. Math. vii. 139. ANCIENT PHILOSOPHY, 1 3 however, looking forth through the portals of sense as through wmdow openings, and reuniting itself again with the outer world, the soul recovers the faculty of thinking. Our nature is in fact es- tranged from the universe, and only as we approach it again through the paths of sense does our nature become anew assimilated to the All, as coals ap- proached to the fire become fiery themselves. All truth, according to Herakleitos, resides in this uni- versal and divine Logos, by which we become thinkers (XoytKoi) ourselves. This is indeed still all very obscure and mysterious, but we see through the dark abysses points where future truth is crystallising already. We hail especially the inter- mediate relationship of sensibility between the soul, still in a state of rest, and the outer world by which it is to be enkindled. The window apertures by which the soul shines forth remind us of the phrase of Leibniz — the monads have no windows through which the outer world can see in. We also see clear indications of a perception that the criterion of truth must be objective, and it agrees with this that Herakleitos is said to have called our ears and eyes liars, since the mere sensible ajDpearance of things always deceives us. It is true the Logos lies in the world without (in the -n-epLejov), and our own being is too far estranged from the world to furnish in itself the central starting-point of all knowledge. Another truth that in our days is forcing its way into daylight is foreshadowed in the thought ex- pressed by Herakleitos — in full harmony with his fundamental principle — that all things proceed from fire, and will be turned back into fire at last. It may be assumed as certain that the philosopher arrived at this truth by refiecting upon organic life 14 ANCIENT PHILOSOPHY. and the degree to which it is determined bv light and heat, even though it may not be necessary to exclude all trace of oriental doctrine and influence. Bu.t we recognise pure Herakleitean profundity in the view that the whole of life is a similar process of opposing movements which are constantly being transformed into their own opposites like a flame or river. One of the Christian fathers, Gregory of Nyssa ^, gives an interpretation conceived in the same spirit : ' With regard to the body, the case is thus : as long as life remains in it, there is an unceasing up and down flow of change ; rest only begins when life has left it. But as long as it is alive, there is no repose, only alternate growth and decay, or rather an incessant intermixture of the two.' After aU its progress, contemporary physiology can hardly give a better definition of life than this one couched in Herakleitean phraseology. Now if we assume that Herakleitos only saw in fire the freest and most rapid form of motion, and in- ferred thence that combustion must represent the primitive condition of all things, so that they were always passing through a course of change, now solid and at rest, then again dissolved into their constituent elements, we shall certainly have to re- cognise in the views of this powerful thinker, whose profundity met with unanimous recognition among the ancients, the first expression of the fundamental ideas which underlie the modern theory of the uni- verse, namely, (i) That the primitive condition of the world is a state of motion, not of rest. (2) That the material substratum of all pheno- mena is an infinitely subtle substance, out of which ' De Anim. et Eesurrect. p. 138, ed. Krab. ANCIENT PHILOSOPHY. 1 5 all others are constituted in forms whicli pass back again into simplicity. (3) That the real objective Being is nothing but motion, whatever phenomenal differences may be thrust upon our notice by the senses. The latter view, which is at the same time the foundation of contemporary science and the essence of Robert Mayer's theories, is warranted by many passages from ancient writers, including Aristotle and Plato, to be genuinely Herakleitean. Thus in the Thesetetos we read\ ' That everything is motion, and nothing else exists ; ' and again, ' According to Homer and Heraldeitos aU things move like streams.' In Aristotle it is said, 'That he (Hei'akleitos) believed everything existing to be in motion, and the majority are of the same opinion ^.' Again : ' Some say that of existing things there is not one in motion and another at rest, and we are always merely deceived by our senses when we fail to perceive this ^' The influence of this powerful thinker was the more considerable because all subsequent systems had either to attach themselves to his doctrine or to deal with it in the way of development or cor- rection, in some cases retaining and exaggerating what was one-sided and so reaching the most curious consequences, and in others endeavouring to reduce this element to its due proportion. Supposing the general estimate of the Herakleitean flux to be correct, in the form in which it has always been reproduced by later writers, — namely, that no- thing really is, but rather is always beginning to be or to cease to be, an eternal becoming, a middle * 156 a. ^ De Anim. i. 2. ' Phys. Auscult. viii. c. 3. 1 6 ANCIENT PHILOSOPHY. state between being and not being \ — then reason would be in some danger of yielding to the temp- tation of playing with its own paradoxes, and the dialectic trifling and tours de force of the sophists, who can prove of anything at the same time that it is and that it is not, might seem nearly related to the Herakleitean doctrine. Epicharmos of Kos was credited with the well-known subtleties about the Delian galley which had been the same since the days of Theseus though every fragment of its wood had been renewed ; that the debtor was not bound to jjay anything to his creditor because both were no longer the same as when the debt was incurred, or that an invited guest is not invited, for the same reason, and the like. The exaggerations of Kratylos belong to the same class; he believed himself to surpass his master, whose dictum as to the impossibility of bathing twice in the same river was improved upon, so that he contended it was impossible to bathe in it even once, since by the time the rest of the body had followed the feet, the water would have run away; he maintained, finaUj^ according to Aristotle 2, that it is impossible to name anythmg, or to mamtain anything ; the utmost possible is to point to a thing with the finger, for everything is m a constant state of change. It is true that Aristotle gives this as the most extreme opinion of the (paa-Kourcov ^paKXeirl- ^eiv, or ' the professed Herakleitizers.' However this may be, the extreme insistence upon change or motion as the sole principle of creation led necessarily to this kind of exaggeration, and hence Plato, Theatet. 152 E: 'Ek Si 81) (j)opas re koI KLv^a-eat Ka\ Kpaa-ias ■npos oKXrika yiyvirai ivdvTa a Sr; (pafiev etcai OUK op9as Trporayopei'oi^rcs' ((JTI. fiiv yap oi&tnoT ovbiv, ae\ Sc ylyvirai. Kai irepl toiVou Trmres e^i]s oi ao(j)o\ n\riv XlappfvlSov ^vp'^epe(Teov, npcorayopas re Km 'HpaKAfirof. ^ Metaph. iii. c. 5. ANCIENT PHILOSOPHY. I 7 to the spontaneous breaking up of the Herakleitean system by the absurdity of the consequences deduced from it. Besides this, there was a concealed contra- diction in the doctrine itself which made a direct correction necessary by means of the nature of human reason, though it is possible that in his own mind Herakleitos had silently effected that correction. All change and transition, all alteration constantly and continuously beginning, necessarily presupposes a something, some being that changes, transforms and modifies itself, otherwise all these predicates would be meaningless and unreal. But if we may trust Aristotle, Herakleitos had always maintained the existence of this One, underlying all change, al- though this assurance is rather weakened, in the passage^ referred to, by the words 'he seems to wish to say.' If, as many ancient writers bear witness, Hera- kleitos regarded fire as the primeval being ^ under- ^ De Caelo, lii. I : Oi 5e ra ^ev aXKa Trdvra ylveirSal re (^atri Kai peTv^ aval 6e Trayitos ovSev^ ev 8e Tt ^OVQV uiro^^i'eti', i^ ov ravra irdvTa fxcrarrx^- IJ.aTi^(a-6ai nc(()vKep' omp eoiKacri ^ouXEaOai Xeyeii' aXXoi re ?roXXoi Kai 'Hpa^Xetroff 6 Ev oi/Vf Tis Beav, otVe dvdpooTrav cVoiijo-ej/. dXX' ijv Kui eanv iriip dei'fuoc, dTTTO/ud'oi/ fiirpa Ka\ aTTOa-jievi'vfifvov ficrpa. ' Gesohichte des Materialismus, i. 12. ANCIENT PHILOSOPHy. 2/ contains the two chief doctrines of modern physics — • the principle of the indestructibility of matter and the conservation of force, reappears in substance in Kant, as the first analogy of experience : Through all phenomenal changes substance persists, and the quantum of it in nature neither increases nor di- minishes.' Kant holds that at all times the persist- ence of substance has been assumed, not merely by philosophers, but by common opinion. The latter is doubted by Lange, who thinks that, under the guidance of the imagination, men have often pic- tured to themselves a beginning out of nothing. And this perhaps is true ; but wherever men have thought rationally, and collected and communi- cated the results of their experience, the propo- sition has passed as an axiom, though perhaps an unconscious one, that has not yet found verbal ex- pression. An experiment might be made without this proposition having been admitted, but it could not be utilised and brought into connection with other data of experience. Ex mere particularibus nihil sequitur ; there can be no science of particulars. Experimental science therefore is without philoso- phical foundation until the universal truths bearing on it have been discovered and formulated. And it is significant that all the chief thinkers of late times, who have endeavoured to deepen the foundations of empiricism and to indicate its proper position in rela- tion to philosophical thought, have always reverted to Demokritos and the foundations firmly laid down by him. It was Bacon who, after a long period of neglect, once more drew attention to the name of Demokritos, and awarded him the palm for genuine scientific inquiry, in contradiction to the current dei- fication of Aristotle. It is interesting also to learn 28 ANCIENT PHILOSOPHY. that Robert Mayer, at the time when he was medi- tating on his great and fruitful principle, used in conversation, according to Rumelin, to repeat again and again: JEx nihilo nihil fit. Nihil fit ad ni- hilum. We might therefore, it seems, call Herakleitos the father of the a p-io7'i philosophy and Demokritos of empiricism. But as the two principles are after all indissolubly connected, notwithstanding the opposite standpoints of the two thinkers, they necessarily meet sometimes upon common ground. According to Herakleitos 'all things change;' according to Demo- kritos ' all things remain ; ' and yet both mean the same thing.. Demokritos started from particular phenomena and brought these into relation with the universe as a whole by means of the negative version of the proposition. Herakleitos, on the other hand, began with the general principle, and to bring this into harmony with the world of experience it was necessary to find a speculative ground for the nega- tive principle of change. All the while the mutable 'aU things' of Herakleitos is objectively identical with the permanent 'all things' of Demokritos. Only the starting-points are diiferent. Demokritos cut a way through the rock for the spreading stream of empirical science, which, fed by a thousand tributaries, was to pursue its course through ages towards the great ocean of human knowledge, which is called upon to give an ever more and more faithful picture of the universe and its inner principles of coherence. Two things were ab- solutely necessary for this result : (i) the sensible, dis- crete, particular had to be taken for the starting- point, and this alone could be defined and fixed by means of number, or the mathematical conception, ANCIENT PHILOSOPHY. 29 which raises them into the firm position of the exact sciences ; (2) the causal connection of plienomena had to be recognised as invariable and unbroken : 'Nothing happens without a cause, but everything with a cause and by necessity.' The atomic theory proceeded from the first re- quirement, and though modern science forms a very different conception of the atoms from that of Demo- kritos, still all exact study of nature points to some- thing of this kind. The second proposition proclaims the principle of natural causality, the invariable law that every effect must be preceded by a cause, as the true key to the knowledge of nature. But the defects and weakness of the atomic theory in its original form must not be overlooked. Demo- kritos explained the motion of the atoms by their falling through space ; he maintained that the atoms were of infinitely varied form, and that all changes in the natural order of things were produced because the larger atoms fell more rapidly than the smaller ones. This detracts nothing from the magnitude of his main idea, that all the qualities which are brought before us by sensible perception may be reduced to quantitative differences in the atoms, which are only distinguishable by their extension and weight, and which act only by way of impact and pressure. Des- cartes, Leibniz, and Locke will return to this prin- ciple hereafter, and Kant will submit it to a searching criticism and trace its justification home, namely in the nature of the pure reason. In all this there is an implicit assumption that mathematics, the theory of the pure relations of space and number, offers the sole and exclusive method available for the explanation of the phenomenal world. Yet ancient materialism did not rise to a 30 ANCIENT PHILOSOPHY. distinct recognition and formularisation of this truth; still less had it attained to the application of mathe- matics to the interpretation of experimental science. Mathematics were still too immature, and the circle of experimental knowledge too restricted. We must wait for the enunciation of this truth till the clays of Descartes, who, living among the triumphs of the empirical method, was himself a great mathe- matician. But the importance of mathematics, their exceptional place among the remaining sciences, and its relation to them all, these points at least did not escape the theoretical consideration of antiquity. It will be sufficient here to refer to the Pythago- reans, who may not have been without influence on the views of Demokritos, a school which had already discerned the important truth that number played the final and decisive part in all things, and that the true ultimate nature of things could only be ex- pressed in terms of number. I do not know that, even at the present day, we are in a position to utter anything more profound or more true than the say- ing attributed to Pythagoras : ' The wisest of all things is Number, and next to this the Name-giver.' Just where the chemist fails to proceed any farther in numerical description, i. e. at the boundary-lines of his exact knowledge, he necessarily begins the use of words to describe the problem, and meanwhile re- gards the chemical elements thus indicated as so many closed doors, through which he knows however that the right way to the ultimate sources of the truth must lead. To him, as to the physicist, to the mineralogist, and even to the biologist, a mental ideal hovers before the mind, according to which all differences are to be reduced at last into pure relations of number, so that the whole universe, at least on its ANCIENT PHILOSOPHY. 3 1 outer side, presents itself as a mathematico-mechanical problem. We know too little of Pythagoras and the sources on which he drew for his inspiration. But however much he may have owed to Egypt, we can- not too much admire the profound originality of the man who forestalled the ripest conclusions of modern science, and was penetrated by the conviction that there was the same principle underlying the har- monies of music and the motion of the heavenly bodies, and that the essential element in all things was ever their numerical relation. It is true that, neither in ancient nor modern philosophy, was any one, before Kant, able to explain the nature and origin of number and the possibility of its genesis. But even among the ancients there was some doubt and hesitation as to the relation of number to actual things and the real opinion of Pythagoras. Thus we are told : ' Not hy number, but according to number, Pythagoras maintained all things to have been originated \' And Aristotle says : ' The Pytha- goreans maintain that things exist only by a kind of imitation of the relations of number ^' In other places he says, on the contrary, that the Pythago- reans considered number to be the real being, the base of all creation ^. It is certain that all Pythago- rean thought was dominated by the fundamental view, that the truth was only to be found in number, and it is also certain that by the application of this principle to physical problems, the Pythagoreans were enabled to reach important discoveries, which ^ Stob. Eel. i. p. 302 : TIvBaySpas oix e| apiBjiOV, Kara Sc apiBimv eXcye navra yiyveadai, " Metaph. i. 6 : Mifirjaei to. ovra cpaa-lv (imi tS>v apidpav. ' Ibid. i. 5 : 'Apxnv dmi koX ws vXt]v toIs oucri. 'Apidp.ov elvai rrpi ov- 32 A^SrCIENT PHILOSOPHY. slumbered through oblivion and neglect for ages, until again brought to light and confirmed by the same method, matured and perfected in later genera- tions. It is weU known that the Pythagoreans had anticipated the Copernican system. Copernicus him- self refers to Nicetas ^ and Philolaos ^- This cor- rect insio-ht was withheld from mankind for some fifteen centuries through the authority of Aristotle. For the rest, the high estimation in which mathe- matics were held by the Socratic school appears from the famous dictum of Plato, MijSeh ayewiuLeTpijTOi elairw, as well as from many other passages, among which the following is especially instructive, as it complains of the neglect of this science among the Hellenes and praises its cultivation among the Egyptians (Laws, vii. 819): 'AH freemen, I conceive, should learn as much of these various disciplines as every child in Egypt is taught when he learns his alphabet. In that country, systems of calculation have been actually invented for the use of children, which they learn as a pleasure and amusement ... I have late in life heard with amazement of our ignorance in these matters ; to me we appear to be more like pigs than men, and I was asliamed, not only on my own behalf, but on that of all Hellenes^.' It might have been supposed that the number- philosophy of the Pythagoreans would have entered into alliance with the atomic theory of Demokritos, and that the empirical sciences, on exact or ma- thematical principles, would have begun at once to flourish among the Greeks. This however was not the case, and Lange throws the responsibility on the ^ As quoted by Cicero, Quaest. Acad. ii. 39. ^ Plutarch, De Placitis Philos. iii. 13. ° Jowett's Translatiou. ANCIENT PHILOSOPHY. 33 Socratic school. ' Undoubtedly remarkable results would have been reached in this way by classical antiquity, had it not been for the reaction which proceeded from Athens against the tendency of phi- losophy towards natural science, and which so de- cidedly obtained the upper hand \' This may be true, notwithstanding that the re- action itself was a stage of the utmost importance in the development of philosophical thought and a great boon to mankind. The more or less avowed hostility against Aristotle and his method entertained by the philosophical re- presentatives of empiricism, from Bacon down to our own times, may have for one of its chief reasons that they saw how, in more than one way, he set aside or falsified the strict principle of natural necessity, the one firm foundation of all empirical knowledge. The introduction of an immaterial elenient, teleology, or the doctrine of final causes, which took up so large a place in the sciences of organic life founded by him, and more especially the dialectical trilling and reasoning from ready-made formal propositions, the imjDortation of logical mental processes into the sober observation of sensible perceptions in the phenomenal world — all this was in direct contradiction to the strictness of scientific method. The salient point of the stand- ing controversy is indicated in the following pas- sage of a distinguished anti-Aristotelian, who was able, nevertheless, to admire the intellectual great- ness of his adversary ^ : — ' In the old world the greatest and most merito- rious student of nature would resort to utterances like ^ Lange, Gesohichte des Materialismus, i. ig. ^ Eobert Mayer, Die Mechanik de.r Warme, p. 247. VOL. L D 34 ANCIENT PHILOSOPHY. this to explain, e. g. the properties of the lever : the circle is such a marvellous thing that it is easily con- ceivable how the motions which produce a circle should also present the most remarkable phenomena. If Aristotle, instead of applying his extraordinary talents to meditations upon the stationary point and the revolving line, as he called the circle, had investi- gated the numerical proportion between the length of the lever and the pressure exercised, he would have become the founder of an important branch of human knowledge. . . . The rule which should have been followed in order to lay the foundations of natural knowledge in the shortest conceivable space of time may be briefly stated. The most obvious and fre- quent of natural phenomena should have been sub- jected, by the help of the senses, to a careful investigation, which should have been continued until the chief conditions, which may be expressed in numbers, had been elicited.' ' These numbers are the sought-for foundation of an exact study of nature.' The influence of Sokrates is generally represented as an energetic reaction against the doctrine and practice of the Sophists. The Greek Sophists bear a striking family likeness to the French revolutionary thinkers of the last century. The vital characteristic of both is a kind of intoxicated self-exaltation of intelligent reason, possessed with an overweeniag sense of its own superiority as it casts off the bandages of the old religious conceptions. It is as true of the age of the Greek Sophists as of that of the French Encyclopsedists, that the morals, which had grown up together with the religious dogmas, were impaired with them, that individualism, sen- sualism, and a superficial rationalism put an end to ANCIENT PHILOSOPHY. 35 all sincere devotion in tlie search for truth and in the investigation of the moral principles of life, until at last an all-destroying scepticism, a dialectic and rhe- toric to which everything was mere sport, threatened to take possession of the popular consciousness. The old dogmas had lost their power, truth and morality needed to be built afresh on deeper foundations. The threatening danger roused among the Greeks, Sokrates, and in the eighteenth century, Kant. 'Between Sokrates and Kant,' says Schopenhauer \ ' there are many points of resemblance. Both reject aU dogmatism, both profess complete ignorance as to things metaphysical, and the speciality of both lies in their consciousness of this ignorance. Both maintain, on the contrar}', that the practical question as to what men should do or leave undone may be ascer- tained with certainty, and this by themselves without further theoretical preparation. It was the fate of both to have immediate successors and declared dis- ciples, who nevertheless departed from their prin- ciples in this very particular, and, cultivating metaphysics, introduced entirely dogmatic systems of their own ; and further, that notwithstanding the great divergence of their several systems, all pro- fessed themselves to be derived respectively from the doctrine of Sokrates, or of Kant.' My plan only allows me to deal with the theo- retical side of the Sokratic philosophy, and that of his successors, in order to show wherein the opposition to the earher doctrine consists, together with the deepening of philosophic thought and its increasing tendency in the direction of what is the principal subject of this work. ' Parerga und Paralipomena, i. 46. D 2 36 ANCIENT PHILOSOPHY. The suLstance of the Sokratic doctrine is a rational psychology, educed from the conviction that human reason is a principle that may be opposed to the powers of nature, which had hitherto received almost exclusive attention, or was at least altogether distinct from these ; that we possess in it a source of eternal truth, amid the deceptions of the senses, a firm and lasting resting-place amid the eternal changes and transformations of all things, and hence too a secure and irremovable basis for moral action and all the higher possessions of mankind, the existence of which was questioned by the Soj^hists, because they derived all such ideas from human convention or ordin;mces, i.e. subjective inclination. This explains why Sokrates occup)ied himself principally with definitions of moral ideas, and what he meant by the often repeated assertion that virtue was knowledge. This may be seen also from particular illustrations. The opposition to the doctrine of strict natural neces- sity of an established external causal chain, appears most clearly in the well-known passage ^ in which Sokrates speaks of Anaxagoras, who first made the modest attempt to introduce a rational principle, the cow, as an explanation of the nature of the world ; and in which he describes his disappointment on finding, instead of what he expected, e. g. explana- tions why the earth is like a dish, why it is best for it to be so, &c., only explanations from natural causes. This was, according to Sokrates, as if some one were to be asked why Sokrates was sitting in prison and then began to explain the act of sitting in accordance with the rules of anatomy and phv- siology, instead of speaking of the condemnation which had brought him there and of the thoughts ^ Pliaedros, 97. ANCIENT PHILOSOPHY. 37 wliich had led liira to reject the means of flight and await his destiny where he was ^. The incompleteness of materialism, or the expla- nation of the world by external mechanical causes, is here plainly visible, and hence proceeds another and far more important principle, which it becomes necessary to investigate. There is hardly any mention in Plato's works of Demokritos and the theory of atoms, but the omis- sion is well supplied by Aristotle. The latter fully recognised the one-sidedness of the materialistic view and pointed it out with great force, a'propos of the manner in which Demokritos conceived the soul as the vital principle of the body. According to this explanation, the soul was to consist of subtle, smooth, round atoms, like those of fire : these atoms were extra- ordinarily mobile, penetrating the whole universe., and bringing about all the vital motions in human beings. ' If this be so,' says Aristotle, ' then there are tivo bodies in every one, and if the infinitely subtle atoms may be conceived as the cause of motion, there is no reason why the same effect should not be ascribed to the larger and coarser parts.' But this, as he expressly insists, does not constitute the essential nature of the soul, nay cannot so much as be an accident of it. The essence of the soul consists in choosino- and knowing, and mechanical explanations, mere causes of motion, can never afford the slightest explanation of the proper functions of the soul, i.e. ' The same thought hsis been expressed by Leibniz wliere he says one might explain Ceesar's crossing the Eubicon by the laws of mechanics, contraction of muscles, &c., whereas to the true un- derstanding of Caesar's step, the whole history of Kome, psycho- logical insight into the remarkable personality of the consul, and much else, were indispensable. 38 ANCIENT PHILOSOPHY. of thought, perception, pleasure and pain, or the like \ Upon this Lange takes up the cudgels and main- tains that Aristotle failed to understand the greatness of Demokritos, which consisted precisely in the rigorous logic with wluch he brought all actions back into the orderly chain of mechanical causation. 'Any system of philosophy which aims seriously at com- prehension of the phenomenal world must return to this point. The special case of those motions which we call rational must be explained by the universal laws of all movement, or there is nothing really explained. The failing of all materialism is that it ends with this explanation, just where the highest problems of philosophy begin. But any one who, re- lying on imaginary rational knowledge, should dabble in would-be explanations of external nature, including the rational actions of mankind, is working to upset the whole foundations of our knowledge, whether his name be Aristotle or HegeP.' This is an outbreak of the animosity above referred to as subsisting between positive and scientific thinkers and the memory of Aristotle. Lange is certainly in the right from the standpoint of the external contem- plation of things, but when we are dealing with the soul, with reason, in a word, with consciousness, the mechanical theory has to submit ; it has a right to be heard, but it is no longer dominant, in fact it is dominated in accordance with its own laws. It was the merit of the Sokratic school to have clearly seen and proclaimed this. A further and more considerable merit may be claimed for Aristotle, in opposition to the material- istic school, namely, his insistence upon the ' final ' Arist. de Anima, cap. 5. ' Geschiclite des Materialismus, i. p. 20. ANCIENT PHILOSOPHY. 39 causes ' or adaptation of means to ends in nature. A vast portion of the whole realm of natural ex- istence and development remains absolutely closed against those who fail to recognise this. These things can only be understood, or indeed exist, with the assumption of an intelligent principle, which does not, of course, mean to say that a maker or creator outside the world has made things as they are, to suit his own purposes or the purposes of mankind. Schopenhauer observes : ' Three great men have wholly rejected teleology, or the theory of " design," and many little men have chanted in echo after them. They are Lucretius, Bacon of Verulam, and Spinoza. But in all three we see clearly the scarce of their denial, namely, that they imagined teleology to be inseparable from speculative theology, of which they had so great a dread as to wish to get out of its way when they scented its approach from afar. . . . The attack of Lucretius (iv. 824-858) upon teleology is so crass and crude as to answer itself Bacon does not distinguish between organic and inorganic nature (which is the point in dispute), but mixes them in his illustrations indiscriminately together. He then banishes final causes from physics into metaphysics, which is to him, as to many even at the present day, almost synonymous with speculative theology. Spinoza could think of no other expedient to bar the way against the physico-theological proof and the view based upon it, that nature exists for the sake of man, than the desperate one of denying any adaptation in the works of nature, a contention which must appear monstrous in the eyes of all who have any knowledge of organic nature. Aristotle contrasts very favourably with these later philosophers, and indeed appears in his most brilliant colours on this occasion. He goes 40 ANCIENT PHILOSOPHY. straight to nature, and is untroiibled by any physical theology. The idea has never entered his mind, and it does not occur to him to look at the world with a view to deciding whether it is a bit of machinery or no. But after honest and diligent study of nature, he discovers that she works everywhere towards some purpose, and he concludes, "Nature does no- thing in vain\" And again in the books De Partibus Animahum, wliich are his comparative anatomy: " Nature does all things for some purpose or other. At every turn we say that such a thing exists for the sake of such another, whenever we see an end towards which the movement tends. We gather from this that there is something of the kind that we call nature. But the body is a tool (organ), for every member is there for some purpose, and so also is the whole." At the end of the books De Gene- ration e Animalium he expressly recommends tele- ology, and blames Demokritos for having denied it, which is just what Bacon, in his prejudice, selects for praise. In point of fact any sane and normally con- stituted mind would arrive at teleology from the observation of organic natiire, but, unless under the influence of inherited opinions, by no means equally at natural theology, nor at the anthropo-teleology condemned by Spinoza. With regard to Aristotle, it should be noted that his teaching, so far as it deals with inorganic nature, is full of errors, as he is guilty of the most serious blunders in the rudimentary con- ceptions of mechanics and physics. But it is quite otherwise in his treatment of organic nature ; this is his proper field, and here we can admire his wealth of knowledge, his keen observation, and his profound insight.' ' De Respir. c. lo. ANCIENT PHILOSOPHY. 4 1 All this Aristotle was able to accomplisli : he might liave become the founder of Natural History, because he saw and recognised the sway of intelli- gence in nature and assigned its due place thereto. But if we compare with the above lucid exposition of Schopenhauer the following passage from a generally sound and serious thinker, we shall see what a vast confusion of ideas still prevails with regard to the interpretation of nature, making the demand for serious inquiry and a return to the metaphysical principles of knowledge an irresistible necessity. Lange says : 'We find in Demokritos no trace of that false teleology which may be called the arch enemy of natural science ; but Ave also find no attempt to explain the development of design ly the blind sway of natural necessity (!!). We know that this last fundamental proposition, common to all materialism, took its rise, in a clear though somewhat rugged shape, from the Hellenic philosophy. What Darwin, with all the abundance of positive know- ledge at his command, has done for the present generation, was done for antiquity by Empedokles, in the simple and momentous suggestion that cases of adaptation abound, because in the nature of things it happens that what serves its pu^yose is preserved, and what fails to do so perishes at once.' What a chaos, a medley of opposite and irrecon- cilable conceptions M And yet the fallacy here iu- ' Still plainer and more startling is the following passage (he. cit. i. 72) about the materialism of the Stoics: 'That sounds sufficiently materialistic, and yet the decisive feature is wanting to this materialism — ^the pure material nature of matter ; the origination of all phenomena, including adaptation and intel- ligence, 6y the motion of matter in accordance mth universal laws.' 42 ANCIENT PHILOSOPHY. volved is no other than the very programme of the majority of contemporary Darwinians : ' To explain everything without exception by exclusively me- chanical causes.' While Aristotle had most to say about Demo- kritos, we find in Plato frequent points of connection with Herakleitos, whose depth received due recog- nition in a well-known titterance of Sokrates. The reaction against naturalism and sensualism, which led naturally, under his guidance, to human reason as the true source of all kiiowledge, roused his greatest disciple to the conviction that it belonged to the nature of reason to be able to separate and re- tain what is durable and persistent, as a fixed pole amid the tmiversal flight of phenomena. This is the first condition required for the existence of any kind of knowledge. For the idea of change itself presupposes that the earlier condition is held fast by the mind ; the content or matter of know- ledge is always something neiv, but never something different. ' We could not take for granted even the possibility of knowledge,' says Sokrates in the Kra- tylos\ 'if everything were changing and had no persistence. For if, for instance, this idea, know- ledge, remains unchanged in all that constitutes it knowledge, then knowledge has permanence and exists. But if the idea of knowledge itself is changed, it becomes transformed into an idea other than the idea of knowledge ; and it is therefore no longer knowledge. But if it were alivays changing, Let us invert the terms — the origination of the motions of matter, including weight and all inorganic movements, by intelligent prin- ciples in accordance with the universal laws of thouo-ht, and the whule absurdity of the proposition becomes evident. ^ Kratylos (Jowett's translation), 440. ANCIENT PHILOSOPHY. 43 there would never be any knowledge at al]^ And for the same reason there could be neither an object nor a subject of knowledge. If however there exists a subject and an object of knowledge, if moreover the Beautiful, the Good, and every other kind of being exists, these ideas obviously bear no resem- blance, as we maintain now, to the current of motion.' We see from this passage, which also contains the germ of the Platonic theory of Ideas, that the func- tion of the reason is virtually that which Goethe characterises in the language of poetry — ' Und was in schwankender Ersclieinung schwebt, Befestiget mit dauernden Gedanken.' Eeason and its conceptions constitute the firm starting-point of true knowledge in the whirlpool of the phenomenal world, sensible impressions, and vicissitudes. And this great truth is of siich sig- nificance that its discovery may also be said to have opened the way for the fiist time to self-examination and self-knowledge. Eeason, or the rational principle (to voinn^oi'), is possession of the ideas, e.g. of the good, the true, the beautiful ; this possession is lasting and un- questionable ; the ideas are recognisable everywhere, and always as the property of the reason. The question is how to find a bridge which will unite these ideas and the phenomenal world of sense and matter. For as to the latter Plato held the Hera- kleitean view of the eternal flux, alternate growth and decay, to be unassailable. At this point the antagonism between the Platonic ^ What Plato was the first to express clearly and convincingly was to be thoroughly established by Kant. 'If time and space were not original possessions of the intelligent subject, there could be no such thing as experience.' 44 ANCIENT PHILOSOPHY. doctrine and materialism first presents itself. To Plato, reason is an active facility of the human soul. Materialism leads necessarily to sensualism, as soon, that is, as it discerns its own incompleteness, and wishes to take the spiritual side of things into account. It explains the latter, like everything else, as an effect. In other words, the senses are stimulated and agitated from without, they feel, and then from out of these feelings the images of the outer world form themselves, the whole intellectual life accomplishing itself mechanically, of itself Sensible perception is not the source of knowledge,- but knowledge itself In the age of Sokrates this view was represented by Anaxagoras, and it was subsequently developed with strict materialistic logic by Epikuros. The images in the understanding are produced by a constant emanation of infinitesimally small and subtle parts from the surfaces of bodies.. In this way copies of the things enter materially into us ; their frequent repetition gives rise to the images of memory, and so the soul, without itself knowing how, attains to thought and a perception of univ^rsals, by the sole constant action of the outer world. Perception and sensibility then remain, notwithstanding the dis- tinctly spiritual (i. e. conscious) character of their nature, imprisoned in the circle of materialism. This opinion is the more probable because the organs of sense, by means of which perception is accom- plished, are themselves objectively perceptible, i.e. material. Hence even Plato ascribes the perceptions of sense directly to the organs, the eyes, ears, and other bodily instruments, while he shows with vic- torious cogency the necessity of an intellectual prin- ciple, which combines, compares, and distinguishes the common element in aU perceptions, and so ANCIENT PHILOSOPHY. 45 penetrates to the essential qualities of things. ' For/ says Sokrates, ' no one can suppose that we , are Trojan horses, in whom are perched several uncon- nected senses, not meeting in some one nature, of which they are the instruments, whether you term this soul or not, with which through these we per- ceive objects of sensed' Sound and colour, taste and smell are different things, but by what power or instrument, asks Sokrates, does that sense take effect which indicates the common qualities of things per- ceived bv different senses, such as beinsf and not- beinff, likeness and unlikeness, sameness and differ- ence, unity and other numbers, etc. Theastetos is compelled to reply that there is no separate organ for these things, but ' the soul perceives the uni- versals of all things by herself^.' The soul perceives equally by the touch the hardness of that which is hard and the softness of that which is soft. ' But their existence and what they are, and their oppo- sition to one another, and the essential nature of this opposition, the soul herself endeavours to de- cide for us, reviewing them and comparing them with one aiaother.' ' The simple sensations which reach the soul through the body are given at birth to men and animals by nature, but their reflections on these and on their relations to being and use are slowly and hardly gained, if they are ever gained, by education and long experience.' ' No one can attain truth who fails of attaining being, and he who misses the truth of anything can have no know- ledge of that thing ; therefore knowledge does not consist in impressions of sense, but in reasoning about them, and the two are not identical ■'.' Starting from this newly-won point of vantage, 1 Thesetetus (Jowett's translation), 184. ^ lb. 185. ^ lb. 186. 46 ANCIENT PHILOSOPHY. ■which Leibniz and Kant were to take as starting- points hereafter, Plato proceeded towards fresh and pregnant discoveries, a part of which still under- lies our whole mode of thought, whilst the one- sidedness of some of his preconceived views has also endured as a legacy of hampering oppression to subsequent generations. The first great truth for which we are indebted to him is that, in order to direct human knowledge to its proper goal in the interpretation of the true nature of things, we must start from knowledge itself, from the peculiar gift of reason which has been allotted to mankind. The 'Know Thyself of the Delphian God is the master-key of which in a happy hour Sokrates and his great disciple have possessed themselves. The student's gaze is turned inwards ; — ' Es ist niclit drausKen, da suclit es der Thor, Es ist iu dir, du briiigst es ewig liervor.' A theory of knowledge is now possible and neces- sary; it was created by Plato and completed by Aristotle with the addition of Logic. This is the positive side. On the negative side must be set the premature conclusion that this reason must be the property of an immaterial substance, the soul, to which pure thought belonged as its sf)eciality. This is again the ineradicable realism of the whole ancient world. Philosophy is striving after being, it insists upon an ontology. As there is a pure thought, it introduces by hypostasis a pure thinking substance. Plato indeed has an easy task in dealing with materialism. For though he could not persuade the Giants and Gods who were fighting about the nature of essence \ and who ' contended that •' Sophist, 244. ANCIENT PHILOSOPHY. 47 the things only which can be touched or handled have being or essence,' yet all thinkers would certainly be on his side when he maintained that justice, reason, virtue, etc. are not material entities, and that the soul to which these qualities belong must therefore also be immaterial. But it is one thing for the soul to exist and another for it to be self-existent, and the problem had to wait till Kant came to give it its due form. Plato exalted the soul into a self-sub- sisting subject of pure thought, free from all de- lusions of sense. He maintained its immortality, and anticipated that after death, when released from the obscuration and fetters of a material body, it would know with far more perfect knowledge the true nature of things. This is set out more at length in the Ph^do (10) and Timseos. The summary of his expo- sition in the latter dialogue is given by Sextus Em- piricus in these words : 'It is an old adage, accepted too by the physicists, that like can only be explained by like. Plato has used this argument in the Timseos to prove that the soul is immaterial. Light, he says, which perceives light, is of the nature of light, hearing which catches the vibrations of the air must correspond to the nature of air, and similarly the sense of smell by which vapours are perceived must be vaporous, and the sense of taste which receives fluidity must partake of the nature of fluids. And the soul too, vi^hich conceives things immaterial, such as the number and limitations within which bodies are contained, must itself be immaterial 1.' The passage is interesting because the reference here is only to the pure forms of mathematics, which Kant ^ Adv. Math. vii. 116, 119. (See also Schopenhauer's Parerga, i. 48.) 48 ANCIENT PHILOSOPHY. will show to be the proper a iwiori material for reason. The second great truth is that thought is accom- plished by means of conceptions and ideas, and that these always contain or represent something uni- versal, different both from material things and from sensible perceptions ; that these abstract, general ideas are the true object of rational thought or in- tellectual activity, and that in them the reason dis- cerns the permanent, essential, and eternal amid the stream of appearances. Tliis great truth, the doctrine of abstract ideas, or universals, sways the whole after- time, remaining as an apple of discord throughout the history of medieval philosophy. It was received as an established fact by all modern philosophy, and, as Locke was the first to see, it will one day yet come to be of the greatest significance for a knowledge of the nature of human reason, namely, when people have become convinced that the history of the origin and development of the human reason may be written at last — by the help of the philo- sophy and history of language. The darker side of the Platonic doctrine of Ideas, which otherwise can hardly be overpraised, is due to the ontological ambition which here again over- reaches itself by transforming these ideas into real, essential, self-subsisting things. We see plainly how Plato was led to this assertion. Like all the other philosophers of antiquity, he regarded as the final problem the question, What is real Being in contra- distinction to appearance, to phenomena l He saw the material world with the correlated sensible per- ceptions in eteinal flux and change, he felt that the reason aspired after permanency, such as it pos- sessed within itself. And thus the material world ANCIENT PHILOSOPHY. 49 was degraded into a seeming existence, a darkening veil, while truth and reality were attributed only to the objects of reason, the ideas. ' First,' he says, 'we must determine what is that which always is and has no becoming, and what is that which is always becoming and has never any being. That which is apprehended by reflection and reason always is, and is the same ; that, on the other hand, which is conceived by opinion with the help of sensation and without reason, is in a process of becoming and perishing, but never really is\' The ideas are the eternal elements to which true being must be conceded. While single beings or material individuals pass fleet- ingly by, arise and decay, we see that their kind lasts on, or, to express it in the more drastic language of Schopenhauer, the ardent adherent of the doctrine of ideas, ' It is the saiue cat that plays in your yard to-day as played and felt and was 4000 years ago.' The ideas are the prototyjDes of things, disguised and obscured by matter in the phenomenal world, which stands with Plato for the manifold, the uncon- ditioned, indefinite, fluctuating, the relative, or in fact for the not-being. Even the soul imprisoned in a body may however emancipate itself from this dark- ness and attain gradually to a comprehension, or rather a recollection of the ideas of things. For all knowledge is recollection. The soul, in its purity, luminous and immaterial, dwelling in a former state of existence with the eternal gods, has beheld in direct vision these ideas or prototypes of things, the creations of the gods. We shall see hereafter how much of profound truth lies hid in this mythological . disguise. The next point to be observed is, that if meta- ^ Timseos, 27, 28 (Jowett's Translation). VOL. 1. E 50 ANCIENT PHILOSOPHY. physics is the science of the inconceivable, upon which rests all the intelligibility of things, and of the truths necessarily presupposed, which the critical reason afterwards discovers for itself, by cautiously eliminating all empirical knowledge and all logical deduction, — then, it must be admitted, the sphere of metaphysics is made too conveniently wide and com- prehensive. To claim all ideas, that is to say, every- thing which human language designates by a word, everything that presents itself as a distinct being in the phenomenal world, whether it be hairs, dust and dirt, or tables and chairs and benches, as an a priori possession of the soul, and to foist it upon the ever- lasting gods, is tantamount to reducing the whole of philosophy to a matter of religious faith ; whereas its chief aim has always been to attain independent existence, and knowledge in the strength of its own nature. To avoid mistakes and misjudgments we must keep before our minds the whole grandeur of the new truth as it appeared for the first time at the dawn of idealism. Other objections and quahfi cations of equal weight have been urged even in antiquity, some of which did not escape Plato himself, if indeed the Par- menides is by his hand. The Platonic duahsm served to accentuate the chasm between the world of ideas and of phenomena, a difficulty which presents the real crux of modern philosophy. Plato's plan was to allow the phe- nomena to become absorbed in the ideas, while the material world was banished into the realms of non- existence. But this is evading, not solving the difficulty, for in all that Plato himself predicates of matter we recognise qualities that only belong to something which has a real existence. That matter ANCIENT PHILOSOPHY. 5 1 opposes itself to the formative power of ideas, that it is that wherein the maker of the world reproduces the ideas as a mechanic works upon his material, that it is not merely an impediment to knowledge by its mutability and diffusion in space, but that it actually sets itself as a bad, ungodly principle in direct antagonism to the creative cosmic forces — these are too grave accusations to be directed against what does not exist. Matter may be the negation of knowledge, but on that account to deny its ex- istence is to identify being and knowing, a course which is easily accounted for by the predominance of the old ontological phantom at this as well as at every other stage in the history of ancient philo- sophy. This difficulty is brought out by Parmenides in the Dialogue^ when Sok rates makes a cautious at- tempt to distinguish between ideas as thoughts of the soul, and ideas as they constitute the imity of things in the phenomenal world. Either the phe- nomenal world must be endowed with intelligence, so that all things think, or it must be able to bear within it thoughts, without however thinking. And when Sokrates suggests that the ideas might be the patterns existing in the realm of being, and single things only copies of them, Parmenides repHes, with justice : Copies exist because of their resemblance to the original, and if the original pattern is an idea, the copies cannot be anything different ; each idea therefore must presuppose another and then another, in an infinite series. And he concludes his objections by admonishing Sokrates : ' As yet you understand a small part of the difficulty which is ' c. 6. E 2 52 ANCIENT PHILOSOPHY. involved in your assumption, that there are ideas of all things, which are distinct from them.' The hmits within which logical idealism is con- fined have remained always impassable. If the mind is self-existing, wholly independent of matter, then all its functions and all its objects may be of an intellectual kind, and there is no possible transition to the phenomenal or the objective world. The only alternatives are, either — To attribute true, external reality to intellectual objects, i. e. to the ideas, as was done by the greatest representative of ancient idealism, Plato, who left ancient philosophy as ontological as he found it; Or — to doubt the reality of external objects and to conceive them either as the product of the mind itself — as it were a true kind of dream — or, again, to bring them into relation with the conscious in- telHgence by a miracle ; and this latter path has been followed by modern philosoj^hy since it ac- cepted, with Descartes, the intelligent subject as the sole starting-point of all our knowledge. Deliverance from the insoluble dilemma was only to be brought to the much-tormented mind of man by Kant, and by no one before him. The reality outside the thinking subject claimed by Plato for the ideas, rightly roused the antagonism of his great pupil Aristotle, whom we have to re- cognise as the greatest representative in the old world of empiricism and the scientific method ; not- withstanding the repudiation and hostihty which he has met with from the modern representatives of the same tendency. He showed how the ideas constituted a second world by the side of the actual one, how they must necessarily remain eternally stationary, disconnected, ANCIENT PHILOSOPHY. 53 ineffective and motionless, liow there could be no causative powei' in the bare idea, since the cause of events lay always in something moving, i. e. in me- chanical natural force ; in a word, all genesis of things from one another, all connection of things one ■with another, becomes impossible as soon as the ideas are supposed to be self-subsisting, individual substances. While Plato had fairly thrown empiricism over- board, Aristotle accepted it as the foundation on which all knowledge must be rooted. In reality single things do exist, this particular horse, this par- ticular tree ; always and under all circumstances thought must proceed from the particular substance, the ToJe Ti, as to which a general statement must be made. The real being is that which is and can be subject only, never predicate. At the same time Aristotle is far from acquiescing in the disintegration of the world according to Demo- kritos, and seeking for explanation among the phe- nomena alone. He is a worthy follower of Sokrates, and knows that we must begin with reason and its functions, with general truths and principles. He demands a jprima ^JiilosopMa whence everything else is to be derived by the mind, but which must serve first as a base for the conception of nature and its general features. He enunciates the great principle that there can be no science of particulars, and also no science of single sensations ; and that universals, abstract ideas, are the necessary factors of the faculty of knowledge. He says, in agreement with his great master, '-^pxh '^«' reXo^ voCs'^. But as to the origin of these abstract ideas, he diverges from the latter, and enters upon an opposite ' Eth. Nic. vi. 12. 54 ANCIENT PHILOSOPHY. course. These ideas are not the original possession of reason, but the latter has only jpotentia, a dis- position to frame and to develope these general notions. They contain, it is admitted, as Plato rightly divined, the essential elements of things. But tlie human soul has a power of grasping and retaining these essentials, which is wanting to the souls of brutes. And, in thus following the reasoning of Plato, Aristotle ascribes ^ separate existence, im- materialness and immortality to the kind of soul which is capable of this special rational thought. But he restricts this concession by saying that if thought is not possible without perception and imagination, the soul cannot be conceived apart from the body. And Schopenhauer^ says with truth, that in other passages, e.g. De Anima, iii. 8, he lays down what has been since formulated in the pro- position, ' Nihil est in intellectu quod non prius fuerit in sensibus ;' so that he denies the condition according to which the soul might be conceived as an independent being. The relationship between Aristotle and Plato may be stated thus, in order to do justice to both : — After Plato had accomplished the task of tracing the organisation and functions of the reason to a certain depth and so casting the light of this one spiritual principle upon the world as it presents itself to the human mind, Aristotle next began to seek, by the light of this knowledge, for the path from Platonic metaphysics to physics ; he sought to vindicate the rights of the actual, of the material world, of sensible perception, and particular ex- istences, and he thus became the philosophical ^ De Anima, i. i. 2 Parerga, i. 48. ANCIENT PHILOSOPHY. 55 founder of the inductive method, whicli starting from the given particulars proceeds by abstraction to the universal and regular. He allowed the rights of reason, but demanded also due regard for the actual and sensible, which, he saw, must furnish the ma- terial for rational thought ; he knew, as Schopen- hauer points out, that all pure and abstract thought has borrowed its original substance from direct ex- perience or intuition. And what constituted in his eyes the essence of things, the universal which was to be apprehended by the reason, the to tI ^v elvai, which makes every- thing what it is "? His answer is, the Form ; a truth which remained long as a dormant germ in the human mind, till at last it unfolded itself with Kant in a rich growth of philosophic clearness. This form however clearly demanded as a preliminary the corresponding notion of matter, and Aristotle has the further merit of having grasped the full significance of this important conception and having assigned to it its place in the general scheme of nature. Matter is the permanent, unchangeable ; all changes take place in it, but they are only changes in the form ; mere formless matter (materia prima) and pure form do not exist, the two are everywhere united {aivoKov). Eational knowledge apprehends pure form, and it is in so far the form of forms. There is a series of beings, so that the one which from one point of view is form, in another is matter. The importance of these luminous principles is evident, and no less so what was incomplete and con- tradictory, and continued to torment posterity ac- cordingly. To the latter category belongs the con- tradiction that anything so external as pure form can constitute the essence of anything, the exaltation 56 ANCIENT PHILOSOPHY. of matter to the dignity of self-existence ^ (or false realism again), and lastly, tlie conception of matter as a pure, formless, passive substance, which must receive its motive impulse and its form from without, i. e. from the world-creating, absolute IntelHgence. The latter is a false conclusion a imori, the origin of which must be pointed out. The Universals or general notions are, according to Aristotle, educed by the human intellect, which is alone capable of this kind of knowledge, from amongst the things presented; the reason comes in contact with the Divine Maker, whose thoughts it thinks again by conceiving their pure forms. The difference between Aristotle and Plato shows itself here also, the former conceiving human reason more as an intelledus ecty])us, the latter as an intellecius archetypiis. With the realisation of the mind and its forms on the one hand, and of matter with its forms on the other, the philosophy of antiquity had reached its utmost accomphshment. Plato and Aristotle are the electric poles which gave this direction to the current of thought for the next two thousand years. The closing period of ancient philosophy may be briefly characterised by a summary of its results. Four elements present themselves as the ultimate elements of being, and must be opposed or reconciled as realities. As it has been the tendency of philoso- phy until Kant to set more and more on one side the self-existent, or 'things in themselves,' the following table will show the connecting link between ancient ^ The effect of this error meets us jarringly in the doctrine of the Stoics. Eeal existence is always material, and therefore, God, the soul, the virtues, the affections, in a word all ideas, must be material. ANCIENT PHILOSOPHY. 57 and modern philosophy and the progress from one to the other. The Thing in itself. Idealism. Eealismi. (Apriorism). (Empiricism). Plato. Aristotle. A. B. a. The Mind. a. Matter. b. The Ideas. b. Form. We shall see how Descartes consciously approached the task of eliminating the subordinate members Ab and Bb, and disputing their self-subsistence. There remained then the two chief opposites, which remained unreconciled till the advent of Kant. In conclusion, I will briefly attempt to show, by the light of a truer theory as to the origin of reason, how the first attempts of this faculty at self-examina- tion must necessarily have led to these great results reached by Aristotle and Plato. The obscure consciousness of this origin and the method conditioned by it served as a guiding star to these great Greeks, who succeeded in carrying to a considerable distance their investigation of the action, nature, and function of reason. Having reached a certain limit, they were unable to proceed further, and assumed some forms of thought to exist a priori, and to be incapable of further solution, which are known by us to be empirical, i. e. capable of historical explanation. But the Greeks did not distinguish between innate and a priori, they took for granted the rational man with all his gifts, and did not dream of seeking for his origin, or the stages of his earher incomplete development. Epikuros alone, whose views concerning the gradual develop- 58 ANCIENT PHILOSOPHY. ment of the liuman race are contained in the fifth book of Lucretius' didactic poem, is an honourable exception to this rule. But as his explanation of the origin of language is throughout materialistic and sensualistic, while the natiire of the reason was not recognised as an object of investigation, no further progress was made beyond this feeble, though me- ritorious beginning. The profound study of more extensive linguistic material and the important results which comparative philology has placed at the service of the philosophy of language enable us to affirm that human reason came into existence with and ly language. General ideas were made possible by words, and they originate with sensible intuitions, but they become exalted, per- fected, differentiated and spiritualised by a gradual growth and evolution continued through the ages. The real point however whence all language and all reason has sprung is the common activity of men and the creations due thereto. In proportion as the latter are multiplied, light is thrown upon the two dark regions, the inner consciousness of man, and the hitherto uncomprehended outer world which is acces- sible to impulses of sense alone. The sensitive, conscious subject is necessarily pre- supposed in all knowledge, but for a length of time this fact remains obscure. By a peculiarity of human reason the objective or external world is intelligible at an earlier stage than what is within. The former serves even as a key to the latter. Before the dawn of reason the external world itself is an object of desire, fear, and hatred, but not of knowledge. But what first made Reason possible ? The action of the feeling and conscious being upon the external world. This effective action marks the real boundary ANCIENT PHILOSOPHY. 59 between two otherwise separate and mutually unin- telligible worlds, the worlds of feeling and of matter. This boundary is the proper domain of reason and of the spiritual formative will ; what is formed reappears in consciousness as perception, but as something well known, famihar, and intelligible. This is the origin of the human faculty of representation or imagina- tion, which grows along with reason, strengthens it, and continues uninterruptedly to act, and to be acted upon by it, so that some eminent thinkers (e. g. Berkeley and Hume) have taken both to be iden- tical, and have held all conceptions to be the same as intuitions or 'ideas,' in the sense in which the word is used by Locke, i. e. mental representations of existing objects. The formative activity of mankind had to pass through its period of development, of slow and con- tinuous progress towards perfection. And this was only possible by the help of language. Language is the echo within of what has been done without, and in this too it serves to connect the external and the internal. But it is much more than this, it obeys the authority of the human will, it is at the present day an instrument upon whose keys (i. e. words) the human mind plays with marvellous skill so as to bring out enchanting harmonies. This power, which now seems to call for such astonished admiration, arose from very trifling and apparently insignificant beginnings : from the circumstance that in the few and unimportant pursuits which were carried on in common by primitive groups of men, certain sounds associated themselves with the action, which dif- ferentiated themselves and gradually acquired the power of recalling to mind these actions and the sensible image of their phenomenal effects. The 6o ANCIENT PHILOSOPHY. cries thus acquired a meaning, and so became tbe germs or roots whence all human speech has been regularly developed^ notwithstanding all differences of sound. This is the origin of words, and it is at the same time the origin of ideas. For words and ideas are inseparable, like body and mind ; they are the same thing under different aspects. A spiritual tradition becomes possible through words, and the community lives a common spiritual life. The same capacity is developed and educated in the younger generation, and the life of the com- munity continues on from millennium to millennium, with heightened and perfected intellectual vitality. We can appreciate now the profound wisdom of Plato in the utterances : ' In these ideas or concep- tions ' — whose dependence upon language he did not conjecture — ' the whole work of human reason is accomplished.' What is the lasting, inalienable pos- session of this same reason ? Surely that which it can ever form and produce again and again at will, its own creations, whereby the contemplative faculties too are constituted, so that the mind learns gradually to conceive the remaining objects of the outer world also in their appropriate forms and to designate them by names. The very word chosen by Plato points to this origin of his doctrine of ideas. That which Plato adds to his doctrine as an appen- dix, or as something merely incidental — namely that human manufactures too, such as tables or beds, are formed in accordance with eternal ideas — appears to us as undoubtedly, what it was unconsciously with him, the starting-point of his theory of the universe. This appears too from the expression which he often makes use of as the equivalent of ideas, patterns ANCIENT PHILOSOPHY. 6 1 (TrapaSeLjimaTa ^), after which the actual beds and tables are supposed to be made ; and again from what he says of the relations between matter and ideas, showing how the carpenter and the smith must be able respect- ively to put their idea of a shuttle or an awl into the iron or wood and so realise it^. The iron and the wood, i. e. the material, are of little consequence, the idea is the principal thing. Thus for Plato, as for the human reason itself in its infancy, the world of human labour furnished the key which was to interpret the mysteries of the world to human reason. We can now understand the connection with the universalia ante rem, and the recollection of a former state of existence. If we start, as Plato does, from reason as an ultimate datum, as an original property of the human soul admitting of no further explanation, it follows necessarily that the smith produces his awl and the carpenter his shuttle in accordance with the idea that is present to his reason. Bvit the question remains how the men of to-day have become familiar with these ideas; how it comes that they are now really creative so that countless objects are formed in accordance with them 1 Certainly only because in the dim remotest past, the thing itself and the idea of it were formed at once by our ancestors, or rather developed out of some still earlier creation. This being, when first created and first thought, passes by tradition into the thought and action of unnumbered ^ Parmenides, 132 (Jowett's Translation). 'The more probaWe view of these ideas is that they are patterns fixed in nature, and that other things are like them and resemblances of them ; and that what is meant by the participation of other things in the ideas, is really assimilation to them.' ^ Kratylos, 389. 62 ANCIENT PHILOSOPHY. generations, and is there constantly renewed, and in fact does only become present to the mind of indi- viduals through a reminiscence of the former condition of the race. In the same way the present generation knows famiharly all the classes or orders of natural beings, because from ancient times the image of them has been imprinted on the mind and thoughts in this particular manner and under these particular forms. Lanp;uae:e has wrouo-ht this miracle: this much is certain, and at the piesent day there is httle diffi- culty in recognising the fact. But we must concede to Plato that this would have been impossible with- out reminiscence, and this is exactly the chief and most fruitful miracle, that the thought and feeling of remotest ages, borne along, as upon a stream, by language, should make its presence felt, on and on in every member of an ever-growing, ever- new humanity. Aristotle too shows clearly in all the features of his doctrine the impress which the origin of reason has stamped upon its whole later development. As he differs from Plato in removing the centre of gravity, of being and knowledge, more towards the objective or actual world, we should expect him to seek his principles also on the objective side of the boundary we have indicated. And this is in fact the case. He gives the name of Matter to the unknown Somewhat, lying in that direction, to which he as- cribes absolute being. The name itself bears on its forehead the tokens of its origin. "YX,] or materia is the timber out of which human activity prepares the most various objects and implements. Generalised the word comes to mean the raw material which is the necessary substratum of all that is done or wrought. That which human intelligence lends to this material ANCIENT PHILOSOPHY. 63 is its form, whicli is the second most essential and important principle for the comprehension of the whole world. But matter is not merely formed and modified by human energy; by some force to us un- known, it is itself always active and creative of new objects and new effects, which forthwith distinguish themselves in form. This matter, which is imperish- able through all the changes of its form, appears properly as a substance, though the active, creative, and formative element is the world-spirit, the Deity. And here we come to the explanation of the uni- versalia post rem. Human knowledge has first to dis- cover these forms in nature, and to make them its own by experience, which becomes possible through reason ; for feeling is the form of what is felt, but the reason is the form of the forms. For the rest, it may be observed that our theory of the origin of reason goes as far to justify the views of Aristotle as those of Plato ; for although the creations of man- kind indeed proceeded from obscure impulses of the will, they only grew into thoughts and conceptions by the sensible perception and contemplation of what was created. They were thus in the beginning more j)os^ rem, and afterwards more frequently ante rem. In many passages of Aristotle we see clearly how the true germs of his fundamental principle lay in this unconsciousness of the origin of human reason and the properties which it has derived from its origin. Thus especially in the famous passage ^ : ' But the soul may be compared to the hand, for the hand is the tool of tools, as the mind is the form of forms.' There is a profound reason for this parallel between the hand which shapes all things and the mind which comprehends all forms. ' All things that become,'- he ^ De Anima, iii. 8. 64 ANCIENT PHILOSOPHY. says in another place, 'must become something as something oiit of something i.' This is just the scheme of human action. But the form is the essential part of the thing, as he says : ' The nature without the matter is what I call the essence of a thing ^.' It has still to be observed that Aristotle, as he combined logic and a theory of knowledge with the explanation from natural causes, reconciled a greater number of principles than Plato, who never passed beyond the sphere of rational thought. His classifi- cation of causes under four categories, which bears a remote resemblance to Schopenhauer's ' Fourfold Eoot,' is a case in point. They are, matter, motion, form, and purpose ; but here too the a jiriori form of human action is unmistakable. As form is the essential point, it becomes the aim of action, and in so far it precedes as (imagined) cause the real effective action (or motive cause). I have expressed my agreement with Schopenhauer in reckoning it among Aristotle's chief merits that he introduced the con- ception of design into the philosophy of nature. It is self-evident that here also human action could only serve as a type and lantern. He observes, with the obvious intention of explaining one by the other, ' If architecture were in the wood itself, it would then work as nature does.' It still remains to note the false a priori track into which Aristotle was beguiled by his point of departure. Because the idea of matter had presented itself to him in the original scheme of hiiman activity, he was led to conceive this as throughout passive and without qualities ; for his highest ideal was naturally ^ Metajoh. vi. 7. ^ Loc, cit., Ae'ym 6' oiiuiav avev vXrjs to ri rjv elvai. ANCIENT PHILOSOPHY. 65 a kind of matter, wMcli the formative human mind might modify and work upon at will, since the form was the essential part of the thing. This separation of the inseparable gave rise subsequently to great contradictions and confusion of thought. The ques- tion arose whence motion was imparted to matter. Aristotle himself only attempted to fill in the gap by the most forced and laboured explanations, or rather, he was obliged to have recourse to a deus ex machina, when he assumed the existence, beyond the starry spheres, of God as the primus motor, the nrpSyrov klvow ukIvtitov, that maintained all things in eternal motion. We shall see how this funda- mental error of a self-subsisting quality-less matter weighed upon Descartes and his successors until Leibniz at last threw daylight on the point, by showing that the true essence of matter lay in action or force. We have seen how the two greatest philosophers of antiquity had sounded the problem of metaphysics to a certain depth, though they were still far from the really final question, considering that one assumed those functions of the reason which admit of histo- rical explanation to be ultimate truths, while the other behoved himself to have attained the source of all reality and its thinkableness by the realisation or hypostasis of matter. They had discerned the natural external forms of rational thought, and believed themselves to have penetrated its inmost nature, and so to have drawn back the veil which shrouded the mystery of being. They took man for granted, and after his image made the world. They were still in the outer court of metaphysics. Much laborious effort remained before a mortal could VOL. I. F 66 ANCIENT PHILOSOPHY. dare to boast of having penetrated to tlie very sanc- tuary and to ask the decisive questions : — What is the last inalienable and unquestionable possession of reason 1 And why does it necessarily think in this wise, i. e. with the fundamental conceptions of matter and form 1 And can we after all ever learn anything respect- ing being itself? Are we not rather confined within the bounds of the original forms of reason, and doomed never to escape from them 1 MEDIEVAL PHILOSOPHY. Ev apxfl rjv 6 \6yos Kai deos tjv 6 Xdyor' iravra 8i avTOv iyev£TO, Koi Xp\s aiiTov eyeyero ouSe ev. — Ev. JoH. i. I. The dark night of the Middle Ages has long been the subject of fable. There is no word of scorn or contempt which has not been hurled at the philosophy of the Schools. This lay in the nature of things. Every age in its youthful pride of life thinks itself justified in picking holes in the work of its bygone, superannuated predecessor, and in clearing the ground for its own new and wiser labours. A still later day does justice to both. It sees that each generation begins its progress by riding on the shoulders of the last, and that even the fiercest opposition directed against the past is only a phase of its continued development.' And accordingly it is now freely admitted that among the much-despised Schoolmen there were thinkers of the first rank, whose names may be set by the side of the most briUiant philosophers of ancient or modern times. But with this we are not now con- cerned. Every age should be measured by its own standard. The human mind was not, as has been imagined, asleep during the thousand years of medi- sevalism ; still less was it sunk in the rigidity of death. There was development, albeit the slow development F 2 68 MEDIEVAL PHILOSOPHY. of autumn, when all the juices are transformed into food and garnered up to nourish in the coming spring the fresh green, luxuriant growth, and supply mate- rial for a new and blooming world. Any one who surveys with comprehensive gaze the development of philosophy as the thought of the world and its relation to mankind, will see in the tranquil intellectaal industry of the Middle Ages a great and significant mental crisis, an important and indispensable link between ancient and modern philosophy. It will be necessary to indicate, as has not I think been done before, the boundaries which separate these three great epochs. I. Ancient philosophy is the philosophy of pure Objectivism. This starting-point is natural. It is the same as repeats itself to-day in the growth and development of every human child in its in- dividual existence. The objective is the truly ex- isting ; towards this all thought and reflection are directed as to the pole-star of true philosophy. The Sophists, who first exalted the subjective element in human knowledge and described man as the measure of all things, were unmasked by the wisest of the Greeks as dangerous, immoral, deniers of truth and virtue, deceivers of men, and given up to ridicule as devisers of verbal snares and entanglements. The greatest achievements of ancient philosophy sprang, characteristically, from the reaction against subjectivism. The Beautiful, the True, the Good, are something real, not mere thoughts or images of human fancy. Sensation is either the means, the tool by which the thinking mind receives the actual world into itself, or it is itself thought, the im- pression or product of reality in man. Even the MEDIEVAL PHILOSOPHY, 69 highest discovery achieved in antiquity, that all knowledge has universals, not individuals, for its object, leads only to the spreading out of these objects in the world of reality either as Platonic ideas or Aristotelian entelechies. Language and reason are one. It occurred to no one that the word as something audible should be separated from the idea as something intelligible ; nor did any one so much as guess at the origin of ideas, as human concepts, and their connection with sensible stimuli and perceptions. The Lockian noogony was incon- ceivable to antiquity; on the contrary, the effort to objectivise, to lend being and reality to all things, prevailed everywhere. The universals had hardly been discovered to be the true objects of human thought, when they themselves became realised either, according to Plato, as specially existing en- tities, side by side with the material things of sense, or, according to Aristotle, as the essential forms of things. That anything should exist only in the human soul, only as perception, thought, or repre- sentative consciousness — such a conjecture never pre- sented itself to the minds of the ancients. Hence aU their art too aims at objective creation. All the philosophical systems of antiquity bear this stamp of objectivity. The Godhead is, even for Plato, the Demiurges by whom the world is formed, and for Aristotle the first motionless mover of the spheres. The enigmatic metaphysical conceptions with which the Middle Ages tormented themselves were curtly set aside. Time is in Plato's eyes identical with the motion of the sun {xP°^°^ ^ "^^^ ovpavov KLvriai's or rfKiov KLvrja-i^, Tim. 37)- And m the same way lie identifies space with matter. Accord- ing to Aristotle, space is something like a vessel, 70 MEDIEVAL PHILOSOPHY. separable from the things which it contains, and therefore neither matter nor form: it is in matter, which is therefore the place of place ; it is that which lies beyond the limits of the terrestrial sphere. Time is, to him, the number of motion, considered as earlier and later. He only once observes, with deep insight, that it might be doubted whether there would be any time, if there were no soul (Phys. iv. c. 14), and decides that if soul or mind is alone able to count, there would be no time without mind. The logical development of objectivism resulted on the one hand in materialism, and on the other in individualism. From the first beginnings of Greek philosophy we see the two tendencies distinguish- ing themselves, when Thales proposes water as the base of creation and at the same time assumes the whole world to be filled with gods^ ; for the gods are individuals who act in or behind phe- nomena. The two principles could only lead to irreconcilable conflicts, for the individual personal powers were only determined by their own wiU and therefore could never become objects of scientific knowledge, while with the conception of matter strict necessity or natural law had been introduced. For this reason Demokritos and his successors are comited as mortal enemies of religion. Hence too the lofty enthusiasm with which Lucretius proclaims the doctrine of Epikuros, and soars above the re- ligious delirium which still enveloped the world in its gloom. It was an enthusiasm proceeding from reason's attainment of self-consciousness, when it first began to recognise in the broad world spread out before it such law and order as constituted its own very nature. Eeason for the first time be- Ba\rjs lorjBrj navra jrXijpi; 6eS>v elvai. Arist. de Anima, i. 5. MEDIEVAL PHILOSOPHY. 7 1 held its own image in tlie mirror of objective ex- istence. And althougli the materialistic school proper did little in antiquity to advance the exact sciences, Lange is right in saying^, ' that merely to refer the enigmatic processes of nature, growth and decay, the seeming disappearance and unexplained renewal of matter, to a single all-embracing, so to speak, tangible principle was itself something like Columbus's egg in the natural knowledge of an- tiquity. All the divine and daemonic goblin array was set aside at a single stroke, and whatever naturally profound minds might be inclined to think of what lay behind the phenomenal world, this world itself now lay -unclouded before the spectator's gaze. Even genuine disciples of Plato and Pythagoras experimentalised or meditated on the processes of nature without confounding the world of ideas or mystical numbers with the immediate data of sense. This confusion, which has been so marked in the philosophy of some modern Germans, only began to appear in Classical antiquity with the general decay of culture in the time of the Neo-Platonic and Neo- Pythagorean rhapsodies.' Lange accounts for this intellectual sobriety by the admixture everywhere of materialistic elements ; but in my opinion it is due to the essential character of the ancient mode of thought, to the naive, unhesitating objectivity which always starts from and proceeds towards the actually existing. The greatest achievement of the old world in moral or practical philosophy, the doctrine of the Stoics, which aspired to make men independent of destiny, and by throwing them upon themselves to raise them above themselves, bears throughout the ' Geschichte des Materialismus, i. 95. 72 MEDIEVAL PHILOSOPHY. stamp of this character. Notwithstanding their affinity with Christianity, which allows some Stoical views to be called distinctly Christian, the Stoics were unable to free themselves from the objective delusion and the supremacy of words; and they maintained accord- ingly the material nature of the Deity, of the human soul, and even of the virtues and abstract concep- tions, relying on the argument that everything real must be corporeal. ' Primum exponam,' says Seneca, 'quid Stoicis videatur, tum dicere sententiam au- debo. Placet nostris quod bonum est, esse corpus; quia quod bonum est, facit ; quidquid facit, corpus est. Quod bonum est prodest, faciat autem aliquid oportet, ut possit ; si facit, corpus est. Sapientiam bonam esse dicunt, sequitur, ut necesse sit illam corporalem quoque esse.' (Epist. io6.) In the same way, justice, courage, soul, virtue, arts, errors, affec- tions, discourse, thoughts, even silence and walking, are corporeal things (Epist. 113). No greater proof of absolute objectivism can be imagined than that the school which taught monotheism, the immor- tality of the soul, the universal brotherhood of man, and recognised virtue and wisdom as the only true good, should have been able to conceive aU human conceptions only as corresponding bodies. The Christian dogma of the resurrection of the body and of transubstantiation had much in common with this doctrine, and among the Fathers of the Church we accordingly find TertuUian adopting as his own the views of the Stoics. The world, according to the Stoics, is the embodied, or objective Logos (XoyiKov etrriv 6 Koarfioi), an Uninterrupted causal mechanism presides everywhere, and all things accomplish their predestined work in accordance with this order. It is in a sense an anticipation of Spinoza's monism. MEDIEVAL PHILOSOPHY. 73 Briefly: What has no objective existence is no- thing. This is the ruling idea of ancient philo- sophy, and hence we see that Plato goes so far as to doubt the existence of matter because of its mutability and perishableness ; while Aristotle ridi- cules the Platonic ideas as phantasms, and in all his investigations into metaphysical conceptions, such as the infinitude of space, etc., always contrives to state the question in this way : ' Is it anything Eeal or not 1 ' Diksearchos, his disciple, is thus quite con- sistent when he maintains : ' Nihil esse omnino ani- mum, et hoc esse nomen totum inane frustraque ani- malia et animantes ap2)ellari, neque in homine inesse animum vel animam, vimque omnem earn qua vel agamus quid vel sentiamvis in omnibus corporibus vivis sequabiliter esse fusam,' etc. (Cicero, Tusc. i. lo.) We have seen that the most various forms of philosophy are possible upon the foundation of ob- jectivity. Materialism, Idealism, Ptealism or In- dividualism, Monism, and all the other systems known to us in later philosophy, grow out of this soil. Their significance and their connection with the common principle of their foundation only appears from the fact that all the difi'erent principles set up agree in possessing the character of reality : Matter, Ideas, Forms, or Individuals, spirituafised bodies, etc., agree in having only a real existence. Even the Scepticism of antiquity does not escape from this mental fashion. When it brings together the conclusions of the different dogmatic schools and says, All philosophical wisdom is nought, this does not mean that the reality of things is called in question, but rather, on the contrary, that man should content himself with realities and not dream of reachmg a satisfactory explanation or true knowledge of the 74 MEDIEVAL PHILOSOPHY. reasons for what exists. There is an existing reality, but the thoughts of men are error and de- lusion. The sceptics urge as a crushing argument against objective dogmatism the incongruities of thought and reahty, the relativity of knowledge, and so to a certain extent the share of the know- ing subject in cognition. With the same weapon at a later date Hume will take up the struggle and give a decisive bent to the course of modern philosophy. The objective points of view had been fairly ex- hausted in the old world ; nothing new remained to be deduced from it. At the same time it had failed to afford any satisfaction, and rather left things with the antagonism between different views at its strongest, and most seriously so in the most pro- found, i.e. the Platonic doctrine, in which scarcely any allowance was made for the essential element in the objective theory of the universe, namely, matter and individualism. II. With the decay of the old culture a new doctrine announced itself, which was to start from the opposite standpoint and thence attempt to com- piehend and explain the universe by a single prin- ciple, — the Christian pliilosophy, namely, which is properly speaking a pure Subjectivism, and might be best characterised as the doctrine of the Absolute Mind. When I say pure Subjectivism, this must not be understood in the sense in which the idea has been made familiar to us by Descartes. There was no discovery as yet of the individual subject, the think- ing Ego, as the source of all knowledge, nor of the great truth which followed on the discovery of the Subject to supplement it, with its necessary com- plement the Object, nor therefore of the polarity MEDIJEVAL PHILOSOPHY. 75 or relativity of human knowledge. But human thought had begun to turn, with an irresistible and growing motion towards the other pole, in order to win there a firm standing-point from whence it might subdue all things to itself The world was made subjective in the person of a God outside the world. As formerly the objective outer world, so now this God is recognised as the source of all being and all knowledge. The highest truths are revealed by him to the human mind, the latter must listen to the voices that speak within, he must learn to understand 'Wie sjyricht ein Geist zum andern Geist.' Nature is still haunted by the shades of the old gods, and is therefore sinful, subject to evil spirits, and full of snares and temptations. To turn away from the world and its seductions, to retire into one's own heart, penance and asceticism, solitary inter- course with God, become the most serious of duties. The renunciation of the bright realms of the objective world naturally leads to mystery and mysticism. We see these accordingly co-operating with the first dawn of Christian philosophy to trans- form and translate the old philosophic doctrine in its own sense ; just as at the close of this whole period, when human wisdom had once more ex- hausted itself in vain, there was a return to the pure primitive spirit of Christianity ui Eckhart, Tauler and Suso, proclaiming the direct beholding of all things in God as the source of all enlighten- ment and the resting on his heart as the sole and highest wisdom. Among the philosophic systems of antiquity there were only two that were akin to the new doctrine and allowed themselves to be interpreted in its spirit : these were the Platonic Idealism, and the 76 MEDIEVAL PHILOSOPHY. numerical harmonies of the Pythagoreans. We see accordingly Neo-Platonists and Neo-Pythagoreans rising out of the ruins of the systems which had perished in the universal flood of scepticism and erecting their new constructions upon the plan and in the spirit of the new truth that is being everywhere proclaimed. Enthusiasm, ecstasy, subjec- tive absorption in infinite depths, — things altogether unknown to the old philosophies, — become powerful and strive towards the ideal which the revolutions of time have brought to birth and before which the radiance of earlier ideals is extinguished as stars in the sunlight, towards the unchangeable, eternal unity, towards the primal being, the pure Christ, whom it is only possible to behold, to divine, to feel immediately, and whose existence the dialectic of the reason will in vain endeavour to deduce from the fleeting and illusory world of phenomena. The sen- sible and the intelligible world are opposed to each other ; the latter is alone true ; the reason rises in the world of ideas above the changes of time and the differences of space. Everything has proceeded by emanation from the eternally one ; but by sin the souls have fallen into the fragmentary condition belonging to life in the material world. The soul therefore has a longing to reunite itself to its source. Schopenhauer is certainly right in pointing out^ the traces of Oriental, and especially Indian or Egyptian influences in the dogmas of Neo-Platonism which became associated with the Platonic doctrine of ideas. For the first time in Western philosophy, we find idealism proper in Plotinos (Enn. iii. 7. 10), where he says, ' The only space or place of the world ' Parerga, i. p. 63. MEDIJi:VAL PHILOSOPHY. 77 is the soul,' and ' Time must not be assumed to exist outside the soul.' The soul thus became the creator of all this side of the world, when it passed out of eternity into time. Hence the goal of all desire is to escape from this temporal birth, this metempsychosis, by renunciation of the things of sense, to take re- fuge in the region where there is no more change or transformation, rising to the pure world of ideas, and thence to unite itself in direct contemplation with God, the world-soul, the eternally Perfect One, to be lost in the abysses of his being and so elude the bondage of imperfect, ever-restless individualism. On the whole, it may be said of Neo-Platonism that it was completely dominated by the new tendency of thought, the opposition of the purely spiritual to everything material ; a more pregnant sign of which can hardly be given than the mention that Plotinos professed to be ashamed of having a body and would never say from what parents he was descended. The thought peculiar to Hebrew monotheism, ' The world is a creation of the Spirit,' offered a suitable channel into which all the longing and aspiration of the ages poured itself, thus determin- ing the whole mental development of succeeding generations. Like the ancient materialism. Christian mono- theism was now to banish the demons and magic terrors of the natural world, which was thus left free, a region no longer closed by fear or prejudice against tranquil investigation or aasthetic contem- plation. One nature served the one God, it was the work of his hands. 'It is a notable characteristic,' says A. v. Humboldt, ' of the nature poetry of the Hebrews that by a reflection of the national mono- 78 MEDIEVAL PHILOSOPHY. theism it always embraces the whole universe in its unity, the life of earth as well as the glittering firmament. It seldom dwells upon particular phe- nomena, but rejoices in flights concerning great masses. One might say that in the 104th Psalm alone the image of the whole Kosmos is traced out.' A more intimate feeling for nature first became pos- sible in Christianity as men allowed themselves to rejoice in the beauty of nature and to imagine and discern the providence and handiwork of the Deity within it, until at length when the days are fulfilled, the time would come when they no more needed to seek in it for light or knowledge. The latter was for a long time withheld. The Gods of nature had been driven away from the old world by the advancing knowledge of nature ; the conflict between faith and reason had resulted, as it always does, in the discomfiture of faith. The heart of man was burning for a new object of reverence, for a new faith that should lend true value to this fleeting life and bring it into relation with the Eternal. It turned away therefore from the cor- rupted nature worship, and sought in purity of heart, in recollection of spirit, in aspiration after the Godhead, for truth and illumination. From gene- ration to generation the chasm was allowed to grow and widen between mind and matter, and men learned thus to look upon the whilom one and undivided as two distinct Beings of different natures. The whole of modern philosophy has been perplexed and tor- mented over the consequences of this antagonism. For the Christian consciousness the reconciliation was effected from the first. Was it not the Spirit which knows and creates and produces all things 1 Poor Plato, poor Aristotle, say the Fathers, you were MEDIEVAL PHILOSOPHY. 79 forced laboriously to seek out tlie architect of the world behind the veil of his works, whereas he reveals himself directly to the soul of every Christian. For a Christian, faith was knowledge and wisdom. To seek for knowledge in nature was to tread the old dark ways, asking wisdom of devils instead of God. As the life of the mind is hidden and can only be expressed by symbols, i. e. by sensible images which must be interpreted in another spirit, it is easy to understand that the first attempts at a Christian philosophy, which were made by the Gnostics, con- sisted of allegorical and phantastical creations of mystical ideas compounded out of oriental mysticism and adaptations from Greek philosophy. They all agree in one point, that an invisible, inconceivable, incomprehensible, immutable, primseval Being is the cause and foundation of all things. This primal monad {/jlovu^ ayyewrjroi) has given birth to all things. He is the Bythos or Abyssus by whom the con- substantial Silence (o-iyi?) was impregnated. Hence proceeded Knowledge (vod?) and Truth, and these four compose the Pythagorean rerpaKTVi, the root of aU things, etc. Metaphysical numbers, aeons, emana- tions, beings intermediate between God and the world, but all of a purely spiritual nature, play a great part. And we see clearly how a spiritual mythology might have been developed, from the unity of the Absolute Spirit, at the root of Chris- tianity, which would have differed radically from the ancient one by its allegorical and mystical form as dis- tinguished from the objective and personal character of the former. Schopenhauer observes with justice^ that the attempt of the Gnostics to introduce middle ^ Parerga, i. 65. 8o MEDIEVAL PHILOSOPHY. beings like the Pleroma, the ^ons, the Hyle or Sophia, between the spiritual first cause and the world was analogous to that made afterwards by Descartes to attenuate the contradictions which the assumption of connection and reciprocal influence between a material and immaterial substance carried with it, such as his assumption of ' animal spirits, nerve-sether,' etc. Both disguise what they cannot explain. The sound instinct of the Catholic Church rose in resistance to this esoteric Gnostic mysticism. The Apologists and Fathers of the Church sought to pre- serve in its purity the simple Christian doctrine, as containing all wisdom in itself and transcending the vain and subtle imaginations of the human wisdom of ancient philosophy. God is a supernatural being, incomprehensible to the reason. What we know of God we only know /rom him, and with this, which is the true Gnosis, we should rest content. There is but one God from whom all things have proceeded and by whom all were created. We can under- stand how in that age of passionate enthusiasm, young ardour, and unbroken energy, Tertullian's faith should have exclaimed, in scorn of reason and all the wisdom of philosophy, ' Credo quia absurdum est : certum est, quia impossibile est ! ' But reason could not long abjure her rights, and the very fact that the Christian apologists were obliged to represent the false gods of antiquity as absurd and irreligious, compelled them to have re- course to grounds of reason to make their con- victions accessible to others. Thus the ^dews of the old philosophers, and especially of Plato, were re- ferred to to show in how many points they approached to the Christian doctrine. They had striven by the MEDIiEVAL PHILOSOPHY. 8 1 light of reason towards that which God had made known by supernatural revelation to Christians. They had as it were stood in the outer court of the temple. But everywhere the opposition between the mind and body was insisted upon as the most important argument. Just as the human mind is one and rules the body with its many members, so there can be but one God to rule the world. 'Deus autem qui est seterna mens ex omni utique parte perfectse consummatseque virtutis est . . . Deus vero, si perfectus est, ut esse debet, non potest esse nisi unus.' (Lact. Inst. i. 3.) It has often been said, that the great idea of Descartes upon which modern philosophy is founded, is to be met with in St. Augustine, who appeals to the certainty of self-consciousness in refutation of scepticism. ' Tu qui vis te nosse, scis esse te ? Scio. Unde scis 1 Nescio. Moveri te scis 1 Nescio. Cogi- tare te scis 1 Scio.' (Sol. ii. i.) And again : 'Omnis qui se dubitantem intelligit, verum intelligit, et de hac re quam intelligit certus est. Omnis igitur qui utrum sit veiltas dubitet, in se ipso habet verum unde non dubitet, nee ilium verum nisi veritate verum est. Non itaque oportet eum de veritate dubitare qui potuit undecumque dubitare.'' (De Vera Rel. 73.) Doubt may prevail as to whether our souls are fire or air, but it is impossible for men to doubt that they feel, will, think and judge, for doubt itself pre- supposes all this. The soul has no certain know- ledge except that of itself : ' Nihil enim tam novit mens quam id quod sibi prsesto est, nee menti magis quidquam prsesto est quam ipsa sibi.' (De Trinit. xiv. 7.) We can only believe in the existence of external bodies, and we depend in the same way upon belief as to the temper, character, and will of VOL. I. a 82 MEDIAEVAL PHILOSOPHY. other men. What we know, we also believe ; belief itself is a way towards knowledge. There are certainly important and remarkable points of agreement between these statements and the fundamental principle and reasoning of Des- cartes. It may be said that Augustine, who so emphatically indicated the direct certitude of self- consciousness, and recognised it as the foundation whence all other certainty must be derived, is the real ancestor of Christian philosophy and Christian Scholasticism, and all that has sprung from these roots. He stands thus in opposition to the whole of ancient philosophy, in which suljjectivity was synonymous with insecurity and deception, and which accordingly strove with all its might towards objectivity or being. But we must not overlook the vast divergences between the Augustinian and Cartesian doctrines, if we are to form a correct estimate of the course of philosophical development. Augustine uses his own consciousness only as a step from which to raise himself up to eternal truth, the certainty of God's existence. ' You doubt 1 ' they both begin ; ' therefore you think. Your thought and consciousness are therefore certain.' But now Augustine continues : As certainly as you live and think, so certaialy God lives and is a Single Being, a spirit like your- self. Descartes takes the reverse way and says : As certainly as God lives and is eternal truth, so certainly is my thought of an external world not delusion. The difference is that mediseval philosophy drew from the world the proof of the existence of God ; Descartes deduced from the existence of God the certainty of the existence of the world. This indeed is certainly his weakest point, but we see already MEDIEVAL PHILOSOPHY. 83 how with him philosophy which had hitherto be- lieved itself to be the doctrine of the Absolute In- telligence, was to become the doctrine of the Sub- jective Intelligence. The knowledge of self was first derived from the knowledge of God. This is perhaps the most im- portant and strongest point of contrast between the age of Christendom and the preceding ancient and sub- sequent modern periods. In brief and notable words Augustine expresses this thought, as at once the rule and the aim of all spiritual research : ' Deum et animam scire cupio. Nihilne plus ? Nihil omnino.' (Soliloq. i. 7.) ' Beus semper idem, noverim me, noverim te.' (lb. ii. 4.) But human reason must re- cognise a something higher than itself, seeing that it is changeable, perishable, and subject to many errors. This supreme, eternal, unchangeable truth is God, and can only be bestowed by him on man. Theology and Theosophy take the place of the ancient ontology. All the incomprehensibility of the world and our own nature is thrown into the shade by the incomprehen- sibUity of the Godhead, which embraces and includes aU that is, but cannot itself be determined or con- ditioned by any name, number, space or time, by any knowledge under any attribute. And these ques- tions as to the nature of the human mind — which by its union with the body is confined within the limits of space and time, wliile at the same time it par- ticipates in the nature of the unconditioned eternal Deity — assumed for the first time a transcendental character. As the one God is present everywhere throughout the world, so the one soul is present indivisibly in every part of the body. It is there- fore a special spiritual substance, which has nothing in common with the corporeal nature. Questions G 2 84 MEDIEVAL PHILOSOPHY. as to the nature of time, space, number, divisibility and the hke, had now become inevitable ; their import- ance and significance only revealed themselves in the course of controversy. But other contradictions of the highest importance, directly connected with the fundamental principle of monotheism or the Absolute Intelligence, presented themselves as well. As ancient objectivism had a decided tendency towards materialism as the prin- ciple of unity and intelligibility, treating individualism as the principle of separation and incomprehensibility, so Christian monotheism leads conversely towards the opposite pole, and takes as its standpoint the unity of the mind, from which and by which all things are created, governed and interpreted, v/hile the foreign and incomprehensible element lies in the manifold multijjlicity, divisibility, and passivity of matter. The scholastic explanation is thus strictly logical in treating time and space, in which all things material are presented, as the real princiina individuationis. Stdl more startling is the contrast between the eternal, unchangeable All Spirit, or God, and the individual spirits which are created and called into being by him : although, in accordance with the principle ' operari sequitur esse,' they cannot be conceived to confront with independent energy the abyss of Omni- potence and creative power of the One. This diffi- culty becomes of the utmost importance because the cardinal question of practical Christianity deals with the responsibility of mankind, which presupposes freedom and independent power. Antiquity might assert the absolute determination of human action by conditions \ Velleius Paterculus might make the ^ Thus, according to Aristotle, Sokrates said Ovk i(f>' ijfiXv yivia-Bai TO (TTTOvbaiovs fivai rj (jiaiXovs. (Eth. mag. i. 9.) MEDIEVAL PHILOSOPHY. 85 divine nature consist in its necessity, as when he says of Cato : ' Homo virtuti consimilhmus, et per omnia geuio diis quam hominibus proprior : qui nunquam recte fecit, ut facere videretur, sed quia alUer facere non ^joterat.' (ii. 35.) But in a yet hig-her degree, whether by his omnipotence or the irresisti- hleness of his workina;, the Christian God must still more inevitably have put an end to all possibilities of individual liberty. The tinest minds accordingly begin at once to torment themselves over this prob- lem, how to reconcile the divine foreknowledge with the free self-determination of the human agent. The logical and candid ones, like Augustine, Calvin and Luther, arrive at the impossibility of human freedom. While the two first hold fast to this, that a great part of the human race ' prsedestinati sunt in asternum ignem ire cum diabolo,' the latter speaks without disguise : 'Concessa prsescientia et omnipotentia, sequitur na- turaliter, irrefragabili consequentia, nos per nos ipsos non esse factos, nee vivere, nee agere quidquam, sed per illius omnipotentiam.' (De Servo Arbitrio.) And in another place : ' We do not exist by free-will, but of necessity; we ourselves do not act, but God acts in us in accordance with his eternal, infallible, un- alterable wisdom ; inevitable logic forces us to this confession.^ In other words, Christian monotheism has an ir- resistible tendency towards Pantheism ; in both the individual existence is completely swallowed in the absolute mind. There is therefore no greater con- trast than that between the ancient polytheism and the pantheism of Vanini, Giordano Bruno, and Spinoza, and only a complete misconception of their nature could lead to an afSliation or even comparison of the two. In the first the individual will breaks through 86 MEDIEVAL PHILOSOPHY. everywhere ; in tlie latter it is wholly eliminated. The scientific knowledge of nature, which only be- comes possible by the denial of the first, had to wage a bitter war against it in antiquity; the latter was accepted and invoked in the renaissance of natural science, as the fundamental prmciple of the new theory of the universe which had become necessary. Accordmg to antiquity the gods dis- played their power by breaking through the laws of causation, as when Jupiter thunders and hghtens from a cloudless sky : Pantheism is the definite expression of a complete natural order, the completed inter- penetration of mind and body, God and the world. The transition was naturally furnished by mono- theism, the belief in the Absolute Intelligence, the creator and ruler of the world, who has ordered all things well and wisely, whose thoughts we think as we learn to know the laws of nature, its classes and kinds ; and whose power reveals itself there- fore not merely in the mighty and terrible con- vulsions of nature, — though these, together with the miraculous contraventions of the natui'al order, bear witness to him too, — but also most profoundly and most purely in the harmonies of things, in the marvellous structure of every living thing, by the side of which all human art and skill seems the coarsest bungling. It is therefore not surprising that we should be encountered at the very beginning of the Scholastic philosophy by an attempt to reconcile Pantheism and Monotheism, in the writings, namely, of Johannes Scotus Erigena, who flourished in the ninth century, and who received his impulse from the pseudo- Dionysius Areopagita, whose works he translated into Latin, so procuring for them considerable in- MEDIEVAL PHILOSOPHY. 87 fluence on the philosophy of the West. In Diony- siup, who was also a favourite authority with the mediaeval mystics, and had himself been much under the influence of Neo-Platonism, attention was for the first time turned to the formation of ideas and logical forms, a subject the study of which was destined to elicit in the future of Scholasticism so much intellectu.al acuteness and so much futile wrangling. According to him there is an afErmative theology [KaTa(pariicn) and a negative, abstract one [aTTocpaTiK^) : the first descends from God to created things, which multiply and specialise as we proceed (in which he is approaching Aristotle) ; the latter pur- sues the opposite course, and by continuously think- ing away, attains to higher and higher abstractions, till at last it reaches the One which embraces all things in itself, being and not-being together, the Un-named, of which nothing may be predicated, the highest knowledge of which consists in negations and is thus the ignorance of mysticism. In Johannes Scotus, who carried out the ideas of Dionysius with closer logic and profounder genius, the difficulty of reconciling the existence of sin and evil with the divine beneficence presents itself as a source of tormenting doubts, and with infinite pains and ingenuity he seeks to lessen the difficulty by treating evil and sin as properly nothing : — 'penitus incausale et insubstantiale !' The other expedient — that God created men free — has been shown by Scho- penhauer in many passages ^ to be a case of ' wooden iron,' since liberty and createdness are essentially irreconcilable notions. For the rest, we find in this remarkable man's ^ E. g. Parerga, i. 67. 88 MEDIiEVAL PHILOSOPHY. writings the germ of all tliat Scholasticism was sub- sequently to set forth at large, and which was to be- come the subject of the most far-reaching speculation and the most embittered controversy. It is interest- ing to observe here the first rise of these questions, and to see how at that date views were allowed expres- sion as harmless which the authority of the Church was to condemn and anathematise a little later. The fact was that in those days of living faith neither the aiithors nor the Church had any conception of the danger of these views and their subsequent destructive effect. Nothing could show more plainly the naive cer- tainty of his belief that all truth was given in the Christian religion, than his frankly expressed con- viction that the true religion was identical with true philosophy; that accordingly true reason and au- thority could never contradict each other, and that whenever the authority of the Fathers, who had themselves been guided by reason only, seemed to conflict with the verdict of true reason, the latter was to be followed. ' Auctoritas ex vera ratione processit, ratio vero nequaquam ex auctoritate.' The whole world has proceeded from God ; his beholding is an act, his act a contemplation ; God is the substance of all things. Man sums up all preceding existence, spiritual and corporeal : — he is a mikrokosm. The conflict between ideas and thino-s forms the real substance of the debates and investigations of Scholas- ticism ; at the same time the Middle Ages were called upon to serve as a period of transition between ancient and modern philosophy, and to prepare the minds of men for the momentous thoiiofht, which is even yet hardly understood, that there is no reality precisely corresponding to the notions of men, and MEDTJEVAL PHILOSOPHY. 89 that what constitutes our reality is simply our own mental representations. The way could only be prepared for this truth by a philosophy which took its start from the absolute intelligence. Aristotle's doctrine of the Categories acquired the utmost importance in Scholasticism : the Categories are properly kinds of affirmation. Lange ^ observes that instead of seeking for the highest wisdom behind the Categories, the fact should have been recognised ' that Aristotle in establishing them was endeavouring to lay down how many principal ways there were of saj'ing about anything what it was, and that he was misled by the authority of language into confusing kinds of propositions with kiods of being.' He then continues : ' Without enter- ing here into the question how far he may have been justified in treating forms of thought and forms of being as parallel, and in assuming a more or less exact correspondence between the two, it must be observed that the confusion of objective and subjective elements in our conception of things, which became in its crassest form the very foundation of Scholas- ticism, is among the most characteristic traits of Aristotelian thought. The confusion was not intro- duced into philosophy by him, on the contrary, he it was who hegan to distinguish between what the unscientific consciousness was always inclined to identify. But Aristotle did not get beyond the very imperfect beginnings of such a distinction ; and exactly those elements in his Logic and Metaphysics, which in consequence of this were most perverse, were seized upon by the untutored nations of the West as the corner-stone of wisdom, just because they ^ Geschichte des Materialismus, i. 159. 90 MEDIAEVAL PHILOSOPHY. were most congenial to their undeveloped under- standino's/ O Truth and error are most strangely intermingled in this account, and the most important problems and achievements of philosophy are altogether ignored or treated as incidental. Aristotle did not distinguish between the objective and subjective elements of knowledge, because this distinction is the ripest fruit of modern philosophy; because the whole of ancient 23hilosophy was essen- tially objective ; and because while the distinction between sensible perception and thought (phenomena and noumena) had been established, that between thought and being was still unknown ! On the contrary, in the eyes of all antiquity the points at which thought was held to aim was (and could not conceivably have been anything but) actual Being (to oVrwf 6V). Logic, dialectic, and the rest were only the sails and mill-stones by the help of which the pure flour of reality was to be extracted unadulterated from the grain. PhUosophy therefore had to pass through a great convulsion before the question of the relation of thought to being could be stated ; all preceding problems had to assume another aspect, as it were turning their shadow side uito the light. This great revolution was rendered possible by the Christian philosophy. Hence the interest and promise of the question, which provokes Lange's shrugs of compas- sion at the outset of Scholasticism : whether the five notions ^ which Porphyry extracted from the logical writings of Aristotle, and his ten Categories, were names, that is to say forms of thought, or real ' Genus, diiferentia, species, proprium, accidens. MEDIAEVAL PHILOSOPHY. 9 1 entities. The whole question of the Universals, with which the Middle Ages were to occupy themselves so much, connected itself with this problem. Thus while antiquity, at its height, could only discern true copies of things in the Platonic ideas, it was reserved for the Middle Ages to consider the nature of thought in itself, — for the thoughts of God were creative too, — and to formulate the problem ' How do we pass from thought to being 1 ' After which the final question becomes possible, 'What is the relation of thought to being 1 ' — which has been an- swered by Kant. Christian philosophy is thus an important and indispensable link in the development of human thought. We cannot therefore agree with Lange in seeing only a sign of 'the barbarism of the western nations' in the disciple and follower of Alcuin, Fredegisus, and his treatise ' De Nihilo et Tenebris,' when he argues that Nothing cannot be a pure negation, but must indicate something real, as darkness does, because every name means something, and therefore Nothing itself must have some kind of being, which is further confirmed by the suggestion that Nothing was the material out of which God created the world. We shall rather see and welcome in this the first crea- tive essays of a healthy vital impulse which com])ares ideas and things, and can therefore proceed to dis- tinguish them. On this untrodden path then Erigena proceeded boldly forward, explaining ' darkness,' ' si- lence,' and the rest as conceptions of the thinking mind. Not less significant is his contention that the absentia of a thing and the thing itself are generically alike, as light and darkness, sound and silence. Aristotle had touched upon this when he distin- guished the airocpaa-ti or logical negation from the 92 MEDIEVAL PHILOSOPHY. a-Tepija-ii or real negation. Here the problem of the relation between thought and being obtrudes itself already; and this important question, which here only appears in the form of an ajjerfu, will meet us again at the period of its approaching solution, in the im- portant work of Kant, ' Versuch den Begriff der ne- gativen Grossen in die Weltweisheit einzufuhren. 1763.' A different hemisphere from that of ancient philo- sophy has been reached when we find ourselves sur- rounded by such questions as, ' Nothing must be something, because every word must mean some- thing ; ' or ' Darkness and Silence are negative in thought ; there must be some real negation an- swering to them.' We are here at the antipodes of the state of mind which accepted as the most positive of certainties that there miist be some- thing in the mind, and that no other starting-point could lead towards the world of things and its re- lations. The new generation was already accustomed to imagine the creative world-spirit surrounded by heavenly beings of a purely spiritual nature, with Seraphim and Cherubim, Thrones, Dominions, Virtues, Powers and Principalities, Angels and Archangels. And as early as Claudianus Mamertus (ob. 477) meta- physical enquiries began as to the immaterial nature of the soul, to which quantity, in the way of exten- sion, cannot be attributed ; whose only magnitude is virtue and wisdom, whose motion is only in time not space, and so forth, in confutation of the antique materialism of TertuUian's views. But the most important conception which me- diaeval philosophy was to originate and bequeath to modern times, was that of the concept (con- ceptus) itself; something purely intellectual, an object MEDIEVAL PHILOSOPHY. 93 born of the mind itself, which nevertheless has mar- vellous unexplained relations to reality, the full elucidation of which remained for a still remote future. To discover these relations began hence- forward to count as the chief business of philo- sophy. All the conti'oversies of Scholasticism turn upon the Universals ; these universals are repre- sented in modern philosophy by concepts, or general ideas. These considerations were- aroused, as has been shown, by the doctrines of Plato and Aristotle. The Pantheistic turn of Scotus Erigena, for whom all things proceed from the Deity as the true substance, and strive to be reabsorbed again in him, who held the highest abstractions to be the highest truths, who understood by the mystical Nothing the supreme superessential, incomprehensible nature of God him- self, whilst on the other hand he makes God the sum of all beings and all realities — this Pantheistic bent prevented the antagonism from becoming sensible as yet : it is needless to add that according to him the Universals exist before the things (i.e. in God) as well as in things. The growing familiarity with the works of Aristotle — so highly revered as an authority — lent to Scholas- ticism its peculiar character. The dialectic method, of starting from ideas and thence, by continued ])ro and contra, deducing true conclusions, was the favourite. It was congenial to an epoch which be- Heved knowledge could only be derived from the mind, and wholly despised nature, reality, and ex- perience. It is unquestionable that the discussion of the con- tradictions between Plato and Aristotle, in the Chris- tian philosophy, helped the latter to grasp its own 94 MEDIJEVAL PHILOSOPHY. problem with a degree of uuity and comprehensive- ness which it could not otherwise have attained. The incurable pluralism of Greek philosophy was really got rid of by Christianity. Instead of the Aristotelian substances, Substance was conceived, its attributes and accidents were investigated, and the idea was actually so boldly generahsed as to include within itself the worlds of matter and spirit. The Pluralism of the Platonic ideas was set aside when for the first time men found themselves in a posi- tion to realise to themselves the growth of ideas ivitliin the human soul, — a clue for all future philo- sophy! From this point of view a passage from Hen- ricus of Auxerre (in the 9th century) is of great interest, as it contains a kind of theory as to the origin of reason, and seems partly, though of course imperfectly, to forestall some of the views of Locke and Leibniz : ' Sciendum autem quia propria nomina sunt innumerabilia ad qua3 cognoscenda intellectus nullus seu memoria sufiicit, h^c ergo omnia coartata species comprehendit et facit primum gradum qui latissimus est, scilicet hominem, equum, leonem et species hujusmodi omnes continet ; sed quia haec rursus erant innumerabilia et incomprehensibilia, alter factus est gradus angustior jam, qui constat in genere, quod est animal, surculus et lapis : iterum h^c genera, in unum coacta nomen, tertium fecerunt gradum arctissimum jam et angustissimum, utpote qui uno nomine solum constet quod est usia ^.' Tliis is genuine NominaHsm ; but what a change in the standpoint compared with that of Aristotle and the ancients ! The latter saw the Universal in thincrs, to and cared for nothing else ; the human soul had only ' TJeberweg, Grundriss der Gescliichte der Philosopbie, ii. p. 125. MEDIEVAL PHILOSOPHY. 95 a special power of perceiving the Universal ; but here we find Christian philosophy, unconcerned about the nature of actual things, — were they not all the work of God ? — boldly maintaining that the soul itself ori- ginates an orderly covirse of intuition and designation. The Christian belief in an immortal, independent, divine soul, was also connected with the avowed ab- solute subjectivity which permitted the development of extreme nominalism and made it possible to say : ' These so-called Universals or kinds, to which you attribute true reality, are only my own creations, or in still harsher form, are the sounds caused by my own mouth, flatus vocis.' A passage quoted by Cousin ^ from the Commentary on Porphyry attributed to Eabanus Maurus is characteristic in this respect ; the object of thought is expressly distinguished from the actual things which alone have real existence : ' Genus est quod prsedicatur. Res enim non prwdicatur. Quod hoc modo probant: si res prsedicatur, res dicitur ; si res dicitur, res enuntiatur; res profertur ; sed res proferri non potest ; nihil enim profertur nisi vox, neque enim aliud est prolatio quam aeris plectro linguae percussio.' It is true the expression is crude, but the thoughtful reader will detect in it the im- plication of a great truth, which was wholly unknown to the ancients. The victory which the doctrine of the Eealists — i. e. those who attributed true reality to Kinds, Universals, or (Platonic) Ideas — gained by the help of ecclesias- tical authority on the occasion of the public decision of the controversy at the Council of Soissons (1092), when the representative of Nominalism was compelled to recant, was owing no doubt to a foreboding of the ^ Ueberweg, 1. c. p. 126. 96 MEDIiEVAL PHILOSOPHY. relationship between Nominalism, logically carried out, and Naturalism or Materialism. The Church felt that its own strength lay in the rigid upholding of the pure spiritual element. The Nominalist doctrine had already shown itself dangerous to the first and highegt doctrine, the mystery of the Trinity. If only single beings possess reality, tritheism becomes un- avoidable, and this point excited universal notice. Every a.ge tests the truth of a new doctrine by apply- ing it to that which it has most at heart ; in the ages of faith this was the Christian doctrine, as in our own day we ask whether the tendency of Darwinism is aristocratic (as Haeckel assures us), or social-demo- cratic (as Virchow inclines to think). The arguments which Anselm of Canterbury brought to bear against nominalism all turn upon the impropriety of judging spiritual natures by the coarse standards of ordinary sense. He ridicules those dialecticians who think that words, the flatus vocis, exhaust the nature of the univejsal substances, who imagine that colour' must be a body and wisdom a soul, who, wholly swayed by their imagination, can only believe in the existence of that which is immediately before their eyes. He calls them dialectic heretics, pointing there- by to the discord which was beginning to separate reason and dogma, while earlier times had remained unshaken in the belief that revelation was completely in harmony with reason and could be demonstrated by the latter. His Credo ut intelligam thus assumes a peculiar character : it may be supplemented : I believe things transcending my powers of comprehension, but which show me the way by which I may attain to true knowledge. The existence of Universals as pure spiritual entities is lighted up by the mysteries of faith, for the comprehension of which they are indeed MEDIAEVAL PHILOSOPHY. 97 necessary : ' Qui enim nondum intelligit quomodo plures homines in specie sint homo unus, qualiter in ilia secretissima natura comprehendet, quomodo plures personte, qnarum singula queeque est per- lectus Deus, sint Deus unus 1 et cujus mens obscura est ad discernendum inter equum suum et colorem ejus, qualiter discernet inter unum Deum et plures rationes ; denique qui non potest intelligere aliud esse hominem nisi individuum, nullatenus intel- hget hominem nisi humanam personam.' (De Fide Trin. c. 2.) The very fact that in the Middle Ages those whom we now call Idealists were called Eealists, is signifi- cant and instructive. It shows the assiimption from which opinion started. The Spiritual was taken for granted, and from thence men proceeded towards reality, asking : Are these Beings conceived by the mind, these Universals, actual things 1 For Plato and Aristotle they were only reflections, e'lSr], iSeat, in the human soul, derived either from memory of a former state or the direct contemplation of real beings in the present. The one view is objective, the other subjective. If the doctrine of Absolute Intelligence forms the real substance of mediseval philosophy, the summit of its unimpaired existence was reached m the well- known cosmological and ontological proof of the existence of a deity furnished by this same Anselm of Canterbury in his Monologium and Proslogium ; which, although their weak points were indicated in the author's lifetime by the monk Gaunilo, yet stood for centuries, like citadels, commanding the whole realm of philosophy, untU at last the mine kmdled by Kant exploded and blew them into the air. The assumption underlying this demonstration is that it VOL. L H 98 MEDIEVAL PHILOSOPHy. is possible to proceed^ by dialectic inferences from thought to being. We think the good, the lofty, the true, therefore these universals have an existence independent of things. But we must then also neces- sarily think a supreme good, a supreme truth, a supreme justice, and this is God, the absolute Being : all individual existences are conditioned, and prove by the very fact that there must exist an rdtimate source, a caitsa jirima, with nothing superior to itself This Absokite Intelligence has created the world, and continues to preserve it in existence : all things existed first in his thoughts, before they attained reality. In individuals nothing is just, good, or true, except in so far as it participates in the absolute Justice, Goodness, and Truth. This is the cosmolo- gical proof, wlrich reasons from our relative thought to the Absolute. The ontological proof, on the con- trary, derives its conclusion from the definition of the idea itself. It is possible to think of a Greatest, a Highest, a Necessary Being : therefore this must actually exist. For if it did not, it would be only in intelledu, it would therefore not be really Greatest, Highest, — id quod non cogitari potest non esse. It is the same proof as that which will meet us again under many disguises in Descartes, Spinoza, and Leibniz, whose dependence upon mediseval thought is shown in nothing more clearly than in this. The ens realissi- mum, necessarium, the causa sui, id quod non cogitari potest nisi existens, the causa prima, all trace their origin to the scholastic argument according to which reality, like any other predicate, is included in the idea of substance, and then by analytical judgment discovered to belong to it of right. No doubt was felt at this period that necessary links of connection must lead from thought, mind, and idea to reality; MEDIEVAL PHILOSOPHY. ._ 99 the impossibility of this was only proved to the world by Kant. The first attempts at reconciliation between the extremes of Nominalism and Eealism were made in the twelfth century, by Abelard, so famous for his eloquence and his ill-fated love. His keen intellect was the first to discern the important distinction be- tween words, as mere sounds, and the conceptual content corresponding to them. Eemusat describes his attitude as follows ^ : ' Ce n'est pas le mot, la voix, mais le discours, sermo, c'est a dire I'expression du mot qui est attribuable a divers, et quoique les discours soient des mots, ce ne sent pas les mots mais les discours (meaning clearly the sense of the words) qui sont universels- Quant aux choses, s'il ^tait vrai qu'une chose put s'afiirmer de plusieurs choses, une seule et meme chose se retrouverait egalement dans plusieurs, ce qui repugne.' He had thus a clearer in- sight into the nature of language than any of his predecessors, while he agreed with John of Salisbury (Metal, ii. 1 7) in thinking, rem de re j)raedicari mon- strum esse. The essence of his doctrine is Concep- tualism, and it seems as if the important determina- tion of the meaning attached to conce]}tus, notion or idea, was also due to him. It was only in harmony with the natural course of things, and of mediseval thought, that he should first locate this concej^his mentis in the Spirit of the Trinity, where its efiects must be creative, aud so turn to the universalia in rebus. If it is, as we believe, one of the most im- portant discoveries of moderii philosophy that all human thought takes place by means of ideas, that these are purely mental objects, which however have ^ Abelard, ii. 105 (ap. Ueberweg, ii. 152). H 2 lOO MEDIEVAL PHILOSOPHY. no other matter or content than what is derived from the objective world of sense, — it will be easy to estimate the importance and the fruitfulness of this discovery of Abelard's. In the same way as he dis- tinguished the word as sound from the idea, he distinguished the latter also from the things to which it refers, and gives it thus a really intermediate place between mind and fact, while he also recognises in words a significatio intellectualis and realis, and says of the definition 'nihil aliud est definitum, nisi decla- ratum secundum significationem vocahuhtm.' The pro- gress is undeniable from antiquity which sought to translate things into ideas, to scholasticism which translates ideas direct into things. For the rest, scepticism was already astir in Abelard's mind, as is shown by his work ' Sic et Non,' in which he brings together all the contradictory propositions which have emanated from authority, and by the utterance which is bold for his age : ' Dubitando ad inquisitio- nem venimus, inquirendo veritatem percipimus.' His doctrines were condemned in two synods. The great schoolmen of the next age, among whom Albert of Bollstadt (Albertus Magnus) and Thomas Aquinas stand out pre-eminent in comprehensive learning and acuteness, accepted the former versions of the problem, of the Universals, and admitted their existence in a threefold sense, as ante rem in the mind of the Creator, as in re, accordina: to the Aristo- telian conception, and also as ]}ost rem as ideas arrived at by abstraction. To Thomas Aquinas the universale in re is the quiddity, or substantial form, which is ab- stracted by the reason, and is distinguished from the accidental forms or non-essential qualities. For the rest, these great thinkers are not unaware of the in- compatibility between reason and the ecclesiastical MEDIEVAL PHILOSOPHY. lOI dogmas. Albert the Great, whose researches were directed towards the hitherto proscribed or despised natural sciences, passed beyond the limits of the credo ut intelligam when he recognised that there were dogmas inaccessible to the natural light of reason, and therefore necessarily objects of faith. He distinguished between philosophic and theological truth, demanding tliat the former should be con- sidered philosophically, and professing in matters of religion to prefer the authority of Augustine to that of Aristotle, while in matters of natural science Aristotle was to be believed in preference. The antagonism appears still more sharply in St. Thomas of Aquin, who confesses most of the dogmas of the Church to be unattainable by natural reason : this can at most prove that they are not contrary to reason, it can never reach them by its own unaided principles and can therefore not demonstrate their truth. On that very account they are matter of revelation, and faith becomes a merit, a virtue, an affair of will rather than of intelligence. Natural theology, as set foith in Aristotle, is, as it were, only a preparation for the higher knowledge of Christianity, and in the same way the light of nature is a handmaid to faith. Here we find demarcations and adjustments where a little later irreconcilable antagonism will present itself. The contrast between the general and the particular, the one and many, reason and sense, which lies at the root of all knowledge, is also at the bottom of this problem of the Universals. The ancients them- selves knew that there could be no science of par- ticulars, nor therefore of affections of sense, and the fact was clearly and precisely enuntiated by both Plato and Aristotle. Each spoke only from his own 102 MEDIAEVAL PHILOSOPHY. standpoint, and under the influence of the prevailing objectivism. Plato attributed reality to ideas ex- ternal to the phenomena, Aristotle to forms within the phenomena. This was the irreducible remainder of ancient philosophy ; what is posited as real cannot be reduced to other elements, it remains individual, and pluralism is the result. The God who orders the world, the mover of all things that move, is a mere expedient. It remains to be seen what answer to the question regarding the individual was given by the doctrine of Absolute Intelligence, or Christian pliilosophy. The most logical reply would have been, as has been said already, that the individual should be absorbed in the former, i.e. Pantheism. But the profound ethical spirit of Christianity was opposed to this ; morality is only possible with self-determination, i. e. indivi- dualism. The individvial, or rather the self-subsist- ence of separate things by and outside the general, universal spirit, is therefore what has to be explained, and of this problem Scholasticism gives various solutions. I. St. Thomas, inspired by Aristotle and his com- mentator Avicenna, placed the principium individua- tionis in matter. It is only by this that species turn to individual beings, and assume material existence in a determinate place and time, hie et nunc. Matter is always undetermined, and has only a quantitas de- terminata, it is the substratum which receives the form, the {nroKelfj.evov or subject. There are, it is true, also immaterial forms, formse separatse, God, angels, human souls, but everything perceivable by sense is a form inseparably bound up with matter. These views include the antithesis of matter and mind, the recognition of matter as the universal substance with MEDIEVAL PHILOSOPHY. I03 only quantitative differences, space and time as their essentia] conditions, form inseparable from matter — all rays of liglit pointing to the path Descartes and Kant are to follow in the future. In Aquinas too we find ideas as to the nature of human knowledge that seem to belong to a later age than his. Human knowledge is only possible by the action of the objects on the knowing soul : one who is deprived of a sense, like those born blind, is without the corresponding concepts; the senses cannot grasp the nature of things, but only their external accidents, and yet the human intellect requires the phantasms of them, which it renders intelligible by its power of abstrac- tion. His criticism on the Platonists is as striking as it is profound and far-sighted : ' Intellectus humani, qui est conjunctus corporis, proprium objectum est quidditas, sive natura in materia corporali existens, et per hujusmodi naturas visibilium rerum etiam in invisibilium rerum aliqualem cognitionem ascendit, de ratione autem hujus naturae est quod non est absque materia corporali. Si j^i'oprium objectum nostri intellectus esset forma separata, vel si formse rerum sensibilium subsisterent non in particularibus secundum Platonicos, non oporteret, quod intellectus noster semper intelligendo converteret ad phantas- mata.' (Sum. TheoL i. qu. 84.) 2. In contradistinction to St. Thomas, Duns Scotus places the essence of Individualism in form, rather than matter. All beings except God have a material, and a form, which is however indefinitely more ex- alted in the case of spiritual than of corporeal beings. But from out of this universal existence, the par- ticular existence of individual beings constitutes itself by the accession of positive conditions, so that the individual nature, the hsecceitas, is superadded to the I04 MEDIEVAL PHILOSOPHY. universal nature, the quldditas. We are generally accustomed to regard these abstractions as the acme of Scholastical absurdity. But it should be re- membered that this last expression means no more than what Aristotle had maintained against Plato, namely, that nothing really exists except the in- dividual, ToSe Ti. Duns Scotus has done nothing but carry the reality of Aiistotle into the higher region of ideas, which is surely an important pro- gress : where else can it belong 1 When Kant comes to exjDlain the case as to this hascceitas, will he show it to be something real \ The analysis of the idea as such and its accurate investigation are due to Scholasticism ; and without this careful anatomy of mental processes modern philosophy would never have become possible. Even Lange does not hesitate to recognise a progress even in the subtleties of the scholastic (Byzantine) logic ^: 'Any one who at the present day is still (!) inclined to identify grammar and logic, would at least derive some profit from the logicians of that century, for the latter tried seriously to make a logical analysis of the whole of Grammar, in the course of which they succeeded indeed in creating a new language, the horrors of which were held to be past exaggeration by the Humanists. . . . But the fundamental intention of all this diligence was perfectly serious, and sooner or later the whole problem (of language and thought) will have to be reconsidered, though it may be with a very different bearing and purpose.' Duns Scotus was an acute but very hierarchically- minded man. He believed himself to be serving the authority of the Church by restricting the lights of ' Gescliiclite des Materialismus, i. p. I'j'j. MEDIEVAL PHILOSOPHY. 105 reason even more than his predecessors, and de- claring the truths which had formerly been recog- nised as the subject of natural theology, such as the creation of the world and the immortality of the soul, to be incapable of proof Knowledge according to his view has nothing to do with faith ; theology has more practical than theoretical significance, the will of God^ is the only cause of the truths of faith ; the duty of man is to believe, i.e. to submit willingly to the authority of the Church. The will of man is not dependent on his knowledge, but he is able to determine it without rational o-rounds ; voluntas est superior intellectu. The breach between faith and knowledge was com- pleted by the Franciscan William of Occam (d. 1347), the restorer of Nominalism. According to him there is no truth of theology, not even the existence of God, that can be proved by rational arguments. He throws a new light upon the enquiry into the nature of Universals and of the individual. Tilings are allowed once more to come within the field of vision. In the golden age of the Christian philosophy the Absolute Intelligence, God, is the source of all truth, the quintessence of all reality, the only true postulate needed for knowledge, and leading necessarily there- to. Now however the long-despised and disregarded object again rises on the horizon in all its enigmatic '■ According to St. Thomas Aquinas, God commands wbat is good, because it is good: according to Duns Scotus, good is good because God wills it. The domain of reason grows more and more restricted. We shall see how, in the next period, its claims grew in the same matters in an opposite direction. According to Descartes, a mathematical proposition is true (an aeterna Veritas) because God so wills ; according to Spinoza, it is an idea of God because it is in accordance with reason. Io6 MEDIEVAL PHILOSOPHY. obscurity, and calls for a solution, which antiquity was unable to give notwithstanding its exclusive attention to this aspect, and which theological wisdom, by re- stricting itself to the domain of faith, could no longer even attempt. But the return to Nominahsm is by no means a simple resumption of the Aristotelian standpoint. In the interval the whole natu.re of the question had rmdergone a change corresponding to the intellectual work accomplished, and though the aspect was the same as from the earher standpoint, the outlook was from a higher elevation commanding a wider prospect. Gradually, and perhaps still con- fusedly and unconsciously, the true objects of the mind, ideas, had been substituted for the Aristotelian objects. Occam hits the weak point of the Platonic doc- trine of ideas, its pluralism. If we make the Uni- versals into real things, existing outside our thought, they turn into single things, individuals. And it is just as impossible to attribute separate existence to the Universals within the things, for this would also be multiplying them. It is we ourselves, our ab- stracting intelligence, that so surveys the really ex- isting single things that the common element belong- ing to them detaches itself and is conceived and comprehended by the mind, only liowever as an Idea, conceptus mentis ; except in the mind, this idea has no existence save as a word or other conventional sign. Thus, according to Occam, the principle of in- dividuation resides in the individual itself, which exists independently and must be accepted as a preliminary part of the problem to be solved. The individuals alone are truly real, 'quselibet res ex eo ipso quod est, est lixc res.' We think and know MEDIEVAL PHILOSOPHY. I07 by means of universals, but it by no means follows that they therefore possess reality. The real in- dividuals are represented in due order and connection by the corresj3onding ideas : these ideas with their verbal equivalents are called termini, and hence the adherents of Occam were rightly called Terminists, to distinguish them from the extreme Nominalists, who saw in Universals mera nomina or arbitrary signs ^- The change may be hailed as the first dawning ray of modern philosophy, since here for the first time the relation of the subject to the object is conceived as the starting-point and fundamental principle of knowledge. For though the termini as such exist only in the percipient mind, they are not arbitrary, like conventional signs or sounds, but they arise by natural necessity out of the intercourse of the mind with things, i. e. as an effect of the latter. Word, idea, and thing seem for the first time to be sharply distinguished and their interdependence shown ; the reason has been forbidden to overshoot herself, Avhile all that follows from the distinction was reserved for future philosophy to explore. The transformation of things into concepts, the origin of concepts, of language and similar problems, may henceforward be detected by keen eyes as luminoiis spots which will disclose themselves after centuries as the beacons towards which philosophy has been directing all her course. Abstraction, the capacity the mind has of forming general ideas, is not an active power of the under- standing or the will, but it accomplishes itself na- turally and inevitably as our perception leaves behiDd it an image in memory (habitus derelictus ex primo ' See Prantl, Gescliichte der Logik im Abendlande, iii. 344 ff. I08 MEDIEVAL PHILOSOPHY. actu 1), and thus the similar perceptions consolidate or melt in one. It follows from this characteristic of our knowledge that it is all founded upon intuition or perception ; which is of two kinds, external and internal. This alone can tell us tliat anything is ; the judgment is then completed by the understand- ing. Abstract knowledge warrants no judgment as to the existence or non-existence of a thing. The senses give us no certain knowledge of things, they only acquaint us with certain signs, which have in- deed a certain relation to them — as smoke to fire, or sighs to pain. Just so words are a-wQ^iKij, arbitrary, conventional signs of ideas, of the conceptus mentis ; they are thus signs of signs, and indirectly of things. Any one who appreciates the significance of these words will feel that a new age has begun since the speculations of Plato and Aristotle, or the words in which Cicero summed up the general theoiy of an- tiquity, ' vocabula sunt notse rerum ^.' Our mind is most exposed to error in the judg- ment respecting external things, suggested by the external kind of intuition. The senses are less to he depended on than the intuitive knowledge of our own inward states. ' Intel lectus noster pro statu isto non tantum cognoscit sensibilia, sed etiam in par- ticulari et intuitive cognoscit aliqua intellectibilia quas nullo modo cadunt sub sensu, cujusmodi sunt intellectiones, actus voluntatis, delectatio, tristitia ■ This expression is much more just than those current in our own day, such as ' Zurtickbleiben von Eesteu,' or, worse still, ' Nar- ben in den Nerven,' and ' schwingende Vorstellungeii,' words without any meaning in particular. Occam touches the two real points, activity and haljit — showing once more how much we have still to learn from the despised dark ages of medisevalism. * Herder, however, repeated this view in the last century. MEDIEVAL PHILOSOPHY. IO9 et hujiismodi quse potest homo experiri inesse sibi, quge tamen noii sunt sensibilia nobis, nee sub aliquo sensu cadunt.' But it is only the states, not the nature or essence of the soul which is to be known in this way. Whether the sensations and emotions, the acts of thought and will proceed from an immaterial being is uncertain^ . Granted that these are only loose blocks rather than a complete edifice, they are the blocks with which the greatest thinkers of modern philosophy, Descartes, Locke, Hume and Kant, liave constructed their great erections. Especially in the two English writers the above argument will meet us in almost the same words. As Occam did not shrink from the ultimate consequences of his views and was prepared to trace back to principles which could only be de- rived from experience, even the syllogistic thought which was supposed to lead to necessary truth and self-evident knowledge, it may be asked whether Locke and Hume are not reallv restorers of his view, according to which experience was implicitly made the sole source of knowledge ; and whether the whole English philosophy of the present day, that of John Stuart Mill, Lewes, and the rest included, is not really standing at the very same point as the Franciscan monk of the fifteenth century. The Church had thus renounced the attempt to regard the truths of salvation as fitted for the illu- mination of reason, or to seek proofs for them in the latter. The attempt of Eaymond de Sabunde, which has been immortalised by one of Montaigne's most interesting essays, to prove the doctrines of Christianity by natural revelation, continued to stand ' TJeberweg, Grundriss, ii. 235. no MEDIJS\^AL PHILOSOPHY. alone. Eeligious faith drew back into its original starting-place, the depths of the human soul. Dis- gusted with the dry intellectual refinements and disputes of the Schoolmen, the finer minds of the ao'e took refuofe in inward revelations, the direct intercourse of the soul with God, and the holy calm of mysticism. The subject seeks with all the powers of the soul to reach and mingle with the Absolute Intelligence, to rest in it, to know and to behold the supernatural truth. The separation between subject and object had accomplished itself in the conscious- ness of the age, and modern philosophy was heralded. The aspirations of the whole preceding period con- centrated themselves in the souls of the chosen few. In union with the object, they said, is true know- ledge only to be found ; let us become one with God. This longing finds its most touching expression in the exhortation of Master Eckhart, the mystic : ' Ach lieber Mensch, was schadet es dir, dass du Gott vergonnst, dass er in dir Gott sei 1 ' To sum up briefly the results of the intellectual work accomplished by Occidental humanity in the Middle Ages, we find : 1. By starting from the Absolute Intelligence, the chief cravings of the reason, after unity and spirit- uality, receive due satisfaction. The individual Gods of popular belief, the in- dividual atoms of Demokritos, the individual ideas of Plato, the individual substances of Aristotle, dis- appear, and in their place there reigns the one God, the one matter, the one svibstance. 2. Metaphysic, something transcending the Ob- jective, becomes possible. The material and the spiritual are separated. The elements of the former are investigated. The way is prepared for Descartes' MEDIEVAL PHILOSOPHY. Ill distinction between extended and thinking sub- stance. 3. The laws of the thinking mind are attentively and assiduously observed. The place of the objects and Platonic ideas is taken by concepts. The special onesidedness of mediaival philosophy consisted in tlae absorption of all individuality by the Absolute Intelligence. The crisis announced itself by the threatening re- assertion of the objective world, as a relapse towards the objectivism of antiquity. But the spiritual standpoint was not to be lost : against the oppressive supremacy of the objective world, the conviction reared itself that the true point of departure must be spiritual ; but it is not the absolute but the individual intelligence that Descartes proclaims as the first and only certainty. In the Cogito the relation of subject and object is implied as the primary condition of all knowledge. It is the vital principle of,piodern philosophy. To investigate this relation, to lay down exactly what belongs to the subject, what to the object, and how they act upon each other, these are the problems for modern times. We shall see grave oscillations towards one or other extreme, till at last the key to the problem is found by Kant ; we shall see the systems of antiquity revive for a time and then, one after the other, pass away for ever. The true deliverance from error is only reached when the source of the error has been discovered. And therefore, in the whole history of the world, no other intellectual feat has had the emancipating power of that of Kant. He will show that there is an element of truth 112 MEDIiEVAL PHILOSOPHY. in every system, but that all are incomplete ; he will show that they have their origin in the nature of the human reason ; and he will lay bare the nature of this reason to its very roots, and so put an end for ever to the controversies of the schools. Thus the development of modern philosophy stretches itself before us as a clearly defined problem at the outset, with a complete solution at the close. The Cartesian Cogito corresponds to the Kantian Dianoiology. We have now to trace the path lead- ing from the one to the other. MODERN PHILOSOPHY. DESCABTES. (1596-1650.) Novs opd Kal vovs dKovet, rakXa Kov]). 'The stone is not in my mind, but only the idea of the stone,' de- clared Plato, and forthwith a separate reality was assigned to ' ideas ' in the world of things. It was Descartes' merit to have conceded real existence only to the universal principles of matter and thought advocated by both philosophers, while denying the real separate existence of objects derived from these and their title to the quality of 'things in them- selves.' The progress involved in this step is too immense to need dwelling on. In this generalising of the two opposites there is involved the reconcih- ation of another opposition which confronts us irre- concilably in the future, from Leibniz to Kant, that namely between the individual and the general. The latter alone can be the object of reason, to which it is akin, on this alone can reason operate and found its corner-stone, the principle of causality. It is exactly their character of generality or universality which invests ideas or forms of thought with their DESCARTES. 1 3 7 value and significance. But reason must not stop short at these or exalt them into special or individual existences, it must press on toward higher principles of tmiversality, from whence these derive their true nature and origin. And this is what Descartes himself did, by exhibiting the two substances together as the true source from whence all intellectual and material forms derive their being 1. There is no organised body, however elaborate its structure, but what must be conceived as a modification of extended substance, i.e. of matter working according to strict mechanical laws ^. This alone will serve to make ' Descartes, Prino. Phil. i. 53 : 'It is true that a substance may be perceived by means of any attribute, but tliere is always one quality which more especially constitutes its nature and essence and to which all others may be referred' (the quality which Spinoza afterwards called ^;a?- excellence ' attribute ' in contradistinction to ' modes '). ' Thus the nature of all material bodies consists of ex- tension in three dimensions, as thought constitutes the nature of the thinking substance or mind. For anything that can be pre- dicated of a body presupposes extension, and is only a state of extended substance ; and similarly whatever goes on in the mind can only be a special condition of thought. Thus we can only conceive figure as something extended, or motion as taking place in extended space; and similarly imagination, perception, and will can only occur in an intelligent, i. e. a conscious being. On the other hand, extension can be conceived without figure or motion, and thought, or consciousness, without imagination or perception ; and the same holds good of the remainder, as every attentive reader will perceive.' ^ 'In the whole of Nature there is thus only one and the same material, to be known only by the fact that it is extended. All its clearly recognisable qualities thus reduce themselves to this : it is divisible, and its parts are movable, and therefore it is capable of all the states which may follow from the movement of its parts. For a merely imaginary division effects no change, all the variety and differentiation of its form depend upon motion. And this has been already observed from time to time by philosophers, who have maintained that Nature is the principle of motion and rest. For they understood by Nature, that in accordance with which all 138 MODERN PHILOSOPHY. everything else conceivable, even though it remains incomprehensible itself. Similarly as to ideas. Ideas themselves are but modes of the thinking substance, of which the only true attribute or quality is thought, including under that term aU forms of consciousness. A broader space is cleared for the transition and develop- ment of forms, of which Aristotle could only indicate the general outline, by breaking down the waU of separation between organic and inorganic being. As Descartes suggests, animals are mere machines. And in the same way it became possible to trace the de- velopment of ideas, and the connection (by favour of the concursus divinus) between them and sensations, or the organs of perception ; a thought upon which it was possible to erect subsequently a system of empirical psychology, tracing the evolution of mind and the intellectual faculties, in opposition to the theoretical psychology of Plato. 3. Descartes credits the soul with the aboriginal possession of certain truths and presuppositions from which all thought necessarily proceeds : e.g. Ex nihilo nihil fit; impossibile est idem esse et non esse, etc. These are ' seternee veritates.' 'It is also en- dowed with certain innate ideas, such as God, sub- stance, thought, truth, extension, and the like ^. There is least room for deception in regard to the truths of mathematics, which are not derived from sensible experience : and the superior certainty universally material bodies assume the forms under wliicli we perceive them.' lb. ii. 23. ^ These views gave rise subsequently to the violent controversy directed against innate ideas, and Locke — who, as a decided em- piricist, never leaves the ground of realism, and wishes to deduce everything from sense-perceptions — was impelled by that very fact towards the true and very important discovery, that the origin of ideas was the point requiring investigation. DESCARTES. 1 39 conceded to the conclusions of geometry arises from the fact that geometricians consider bodies only as magnitudes occupying space. 'We enumerate different parts in space, and ascribe size, form, and local movement to the parts, and a certain duration to the movements. Meanwhile we are not only fully acquainted with all these general conditions ; we are also able to discern, on directing our attention to them, innumerable special facts concerning forms, number, motion, and the like, the truth of which is so completely in accord with our own nature that its discovery does not affect us as something new, hut rather as something formerly known and now remembered, or as if our attention had just been called to something that was in us before, though the eyes of the mind had not yet been directed to it. And the most remarkable thing is that we find in ourselves innumerable ideas of things, which, although not to be observed without difficulty, yet cannot be treated as non-existent ; and whatever we may choose to think of them, they possess a true and unchangeable nature, and therefore cannot be the creatures of our inventive fancy. Thus, for instance, different properties of a triangle may be demonstrated so that we have to admit their truth, although we had never thought of them before as belonging to the idea of a triangle.' (Meditationes, i.) On the whole we must recognise in these views of Descartes an im- perfect expression of the doctrrue, afterwards laid down by Kant, of the a p'iori, or the metaphysical postulates of human knowledge. 4. Everything in the material world is accomplished in accordance with mechanical laws ; hence all pheno- mena must be referred exclusively to efficient causes, The soul is powerless to effect any change, since the 140 MODERN PHILOSOPHY. quantity botli of matter and motion in the universe remains eternally the same ^. 1 In this connection (Princip. Pliilos. ii. 36) Descartes eminciates for the first time the principle of the conservation of force sub- sequently developed and demonstrated by Eobert Mayer : ' For although this motion is only a state of the matter moved, it yet forms a fixed and definite quanhtm, which may very well remain the same in its totality throughout the world, notwithstanding the changes in single parts, as when the rapid motion of a small body communicates slower motion to a large body, so that in propor- tion to the loss of motion in one body is the increase of impetus conveyed to another.' . . . And it is altogether rational and in accordance with the idea of God as an immutable being . . . ' that God who has allotted different motions to the various portions of matter at their creation, should also maintain the same amount of motion therein, as he maintains the matter itself of the same kind and in the same relations as when created.' The relation of motion to rest was also clearly developed by Descartes (Princip. Philos. ii. 26) in the same sense as the Leibnizian formula, that rest is only a kind of motion, which has given rise to the distinction, of so much importance in modern science, between vis viva and tension. ' For I must observe,' he says, ' that we labour under a great prejudice when we assume that more energy is required for a state of motion than of rest. "We take this for granted from child- hood onwards, because our own bodies are moved by an act of will, of which we are always conscious, while they are fixed to the ground when in a state of rest, by their own weight, of the action of which we are unconscious. For weight and other causes un- perceived by us resist the motion we wish to communicate to our limbs and produce the feeling of weariness, and thus we imagine a greater degree of activity and force to be required in initiating motion than in arresting it, since we attribute to other bodies the same kind of effort with action as we are conscious of in our own members. But we may easily disabuse ourselves of this prejudice by reflecting that we have to make this effort, not merely in order to move, but also to arrest the motion, of external bodies. Thus it requires no greater exertion to push off a boat lying in still water than it does suddenly to stop the same boat when it is moving, or at least scarcely any greater, for we must allow for the action of gravitation and the resistance of the water, which by themselves would cause the motion to come gradually to an end.' DESCARTES. 14I The mind however is perfectly well able to determine the direction of the movement, by making use of the efficient causes, under favour, of course, of the concursus divinus. This is an important truth, and serves to explain both the fact of organic develop- ment and the supremacy of man over all other beings. And, in proportion as, after continual expeiiments and attempts, men's technical capacity culminated in the acquisition of tools, whereby, in accordance with mathematical principles, their insight into the nature of efficient causes was enlarged ; in the same pro- portion they were enabled increasingly to direct the motions of nature towards their own purposes, and to rule and regulate an ever increasing quantity of natural force. But, at the present day it is hardly ne- cessary to observe, that amidst the enormous changes wrought by man over the whole surface of the globe, no particle of motive force is either created or destroyed. 5. Another important and fruitful discovery is that of the relativity of all motion : the bearing of which upon the Critik der Beinen Vernunft may be indicated here. For if the chief merit of the latter work lies in its having demonstrated the relativity of all human knowledge, and shown the impossibility of passing thence to the Absolute, an important step towards the truth was surely won, when it came to be seen that in the whole of this objective outer world no change can be conceived by itself, but only in relation to something else. ' In order to determine the place of a thing, we must look at other bodies which we assume to be stationary, and as we look at it in relation to different bodies at the same time, we may say that it is both in motion and at rest. If a ship is sailing on the sea, a man seated in the cabin remains in the same place, if he 142 MODERN PHILOSOPHY, considers the parts of the ship, to which his re- lation has not changed, but at the same time he is constantly changing his place in relation to the shores which he is leaving and those to which he is approaching. And if we assume further that the earth is in motion and proceeding just as far from west to east as the ship is sailing from east to west, we must say again that the man in the ship does not change his place, as determined in relation to fixed points in the heavens. If however we further assume that there are no such fixed points in the universe, we may conclude that no spot in any object is really motionless, but is only arbitrarily so considered.' (Princip. Phil. ii. 13.) 6. We have already observed that the systems of Demokritos and Epikuros show a direct relationship to the purely mechanical conception of nature ; but it was also an important advance upon their doctrines when Descartes dispensed with the idea of a vacuum, which they had assumed as the only other requisite for the universal dance of atoms, and which he showed to rest on prejudices implanted by common experience. In point of fact, the rarity or density of bodies depends upon the interstices or pores which are themselves occupied by other matter of greater and greater rarity. This conception requires one important cor- rection, which was supplied by Kant, that bodies are really only so many spaces, filled with force, but that there is no intellectual impossibility in the way of our conceiving such force to become gradually in- definitely difiused, and consequently enfeebled. StUl Descartes must be allowed the merit of having been the first to oppose the crude atomic theory, which was obvioi;sly derived from the prejudice above referred to. DESCARTES. I43 « We may now turn to those sides of the Cartesian system which contain obvious weaknesses and incon- sistencies, which the future development of philosophy was called upon to reconcile or eliminate. And of these first of all : — I . The definition of body. According to Descartes, the nature of body is hardly distinguishable from that of the space wliich it occupies. Extension is the sole property of extended substance, or the material world. ' We must know,' he says, ' that the nature of matter or body in general does not consist in hard- ness, or weight, or colour, or any other sensible quality, but only in its extension in length, breadth, and height. For weight, colour, and all such qualities which are perceived in matter, may be set aside, as well as hardness, and yet the material thing con- tinues to exist, and therefore its nature cannot be de- termined by any of these qualities. (Princ. Phil. ii. 4.) ' Nothing obliges us to regard all subsisting bodies as sensibly perceptible.' (lb. 7.) 'For it is only in thought, not in reality, that magnitudes are distin- guished from extended substance.' (lb. 8.) ' We shall easily see that it is the self-same extension which constitutes the nature of body and the nature of space, and that one can no more be distinguished from the other than the nature of the species from the nature of individuals, if we abstract, e. g. from our idea of a stone everything that does not belong to its nature as a body. In the first place we may eliminate the idea of hardness, which the stone loses, without ceasing to be a body, if it is fused by heat or ground to powder. Colour may be eliminated, as there are transparent or colourless stones ; weight, for there is nothing lighter than fire, which is nevertheless counted as a body; finally, cold and heat and all other 144 MODEKN PHILOSOPHY. qualities, because we may not have observed tbem in the stone, or may know that their loss or change would not affect the material nature of the stone. We shall thus see that in the idea of the stone, scarcely anything will remain except extension in length,' breadth, and depth, which exists equally in space whether occupied by matter or void.' (lb. ii.) For this reason too a vacuum is impossible, ' because the extension of space, or a place enclosed by the ex- tension of matter, are the same thing,' and because it would be absurd to attribute extension to nothing, (lb. 1 6.) 'If God removed all the bodies contained in a vessel, its sides would touch because there would be nothing more between them.' (lb. i8.) In a word, ex- tension, space, and matter are the same, or nearly the same — they are substantia extensa. It is apparent how even this lucid thinker was led to confuse sub- stance with its sole attribute, extension, to such an extent as to ascribe reality to non-existerLce — the mere form or possibility of extension — only because the same word was used as in characterising reaUy ex- isting extended objects. In many passages however he seems on the verge of truth, as when he discerns that there is a material difference between the exten- sion of bodies, of which the forms may change with- out involving more than a change of place, and the extension of space, which is always assumed to be universally one and unalterable. (Princ. Phil. ii. lo, 1 2.) But he concludes the section which is devoted to this consideration with the express declaration, ' I recog- nise no other matter in the bodies of things than that divisible, figured, and moveable substance which geometers call magnitude and take as the subject of their demonstrations, and I recognise nothing as real in this matter except such divisions, figure, and DESCARTES. I45 motion, and whatever may be deduced with mathe- matical certainty from those universal ideas. And as all natural phenomena may be explained from these, I cannot consider any other principles of natural science as either trustworthy or desirable.' (Princ. Phil. ii. 64.) The central truth is here in view, scarcely veiled by the accompanying error. What cannot be ex- plained mathematically, cannot be explained at all ; the mathematical is the only method applicable to reality, and to make the use of it possible, it must have one single universal quality to deal with : this is dimension, a mode of extension. If at the present day we have just ideas as to the nature of body, if we have learnt to regard impene- trability and weight as inseparable from the idea of it, we are still bound to remember that all these qualities are based in the last resort upon the idea of space, and that the latest result of the Critique of pure reason applied to bodies is to define the objective world as 'that which moves in space.' We shall then admire the vigour of the intellect which first grasped the idea that the true reality of all existing things must be deduced from the ideas of space. The dif- ference may be stated thus : Descartes, starting from the idea of substance, and beheving accordingly in the external world, was compelled to look on space as something real, otherwise all those bodies which existed as space-ideas would lose their reality also, while Kant, who was deeply convinced of the ideality of space, was compelled to transform the things existing in space also into ideal forms. Both how- ever saw clearly the prime necessity which made 'only one nature and one science of nature' pos- sible. VOL. I. h 146 MODERN PHILOSOPHY. 2. The assumption of specific differences in the bodies originally created by God— i. e. in different parts of extended substance— was a grievous burden, left by earlier schools of thought, and impaired con- siderably the simplicity of the mechanical theory and the possibility of explaining everything by a single principle. According to Descartes every body has an external superficial extension (its apparent volume), and an internal extension which is limited by the si^e of its interstices or pores. As there is no vacuum, each of these spaces is again filled by some thinner bodies— how they can be so is not exactly explained — and changes of form only take place by means of changes in this inner space, that is to say by the con- traction or expansion of the walls of the pores. There is thus given us a multiplicity of material beings, even though their differences may be only modes of extension. But this involves a rigid separation of the original substances, and the wholesome prin- ciple of transition, of the rise of one form from another, because of the essential unity of matter, has its action interfered with. A new kind of pluralism, therefore, is introduced in the midst of the material world, and is left for the future to dispose of Accord- ing to Descartes, the different modes of extended substance were created by God, who at the same time set each of them in motion. Both the material sub- stances and the quantum of motion in the whole re- main the same for ever ; there are only changes of place and form, effected by the communication of motion, by pressure or impulse. This unexplained opposition between matter and motion arises from the necessity of our nature to imagine a subject for every activity, and therefore also for every motion. And here, as has been said, the path of progress leads us DESCAKTES. 147 past Leibniz to Kant, who will show us that bodies, in relation to our thought, can be nothing more than an x of which we can only predicate one quality, viz. motion, or change of place. But we must not overlook the fact that this distinction between matter and motion, as laid down by Descartes, is in a certain sense pre- liminary to the attainment of greater clearness ; for on the one hand, the conception of motion in its sim- plicity, and on the other the conception of matter as a purely space-idea, seem in a measure to involve the elements of Kantian thought. 3. The unexplained duahsm of the suhstantia cogi- tans and substantia extensa not only jars upon the most general and wide-spread convictions, but it results also in obvious internal contradictions. Not even the driest and dreariest materialist, not the most fanatical theologian would be willing at the present day to iden- tify himself with Descartes' reiterated view that ani- mals are nothing but very skilfully constructed, soul- less machines. Further, the destruction of the human machine, i. e. of the human body, is followed by death, disturbance or confusion in the machine is followed by abnormal determinations of the will and of know- ledge. But if the soul is dependent to this extent upon the machine, it cannot well be regarded as a self-subsisting thing in itself, a substantia cogitans. In spite of this Descartes remains faithful to the great truth that the body can never be conceived as the cause of the soul, or the latter explained by its help. 4. Notwithstanding the simplification undergone by the idea of ' substance,' it still remains a heavy burden, imposed by the past and acting as a drag upon all real progress towards the goal of philosophical reflection. The persuasion of antiquity that all speculation must take its start from Being, was L 2 148 MODERN PHILOSOPHY. shaken to its roots by Descartes' deep and searching doubts, and in its place the notion dawned that the true point of departiire was to be found in the thinking subject, a ground that has never since been abandoned by modern philosophy. But as soon as the predicate of consciousness was discovered as something vmquestionable, the idea of substance fortliwith presented itself, as the existing support and subject of the predicate, and hence arose the suhstantia cogitans. The exclusion of everything external, manifold, various, or divisible, as given in extension and space relations, from the uniform, inward, unextended region proper to consciousness, necessitated the assumption of a second substance, having nothing in common with the first : and hence arose a chasm that could neither be closed nor bridged. A special difficulty is placed in our way by the suhstantia cogitans, which, according to the ex- pression of Descartes, has dived into the body. For although it may be easy to recognise in extended matter stretching itself in aU directions through space the one united self-sustaining substance con- ditioned in all its parts by unbroken causal and mechanical connections, a similar connection between different minds, as parts of a single substance, is abso- lutely inconceivable, the rather as the minds must be shown to exist in definite places, whde they are separated from each other by intervening bodies. This spiritualistic tendency of Descartes, if logically followed up and developed, led with necessity to the theory of Malebranche, who speaks of God as the 2dace of spirits, and consequently adds, ' Nous voyons tout en Dieu.' But what is the ' place of spirits ' 1 Obviously only a mythological expression, suggested by the idea of a spiritual substance, and serving to DESCABTES. 1 49 reinstate the inevitable idea of space at the very point from which it had been banished. The idea of substance, towards which philosophical speculation is constantly being attracted, labours under one fundamental disadvantage, a disadvantage that lies in the nature of human thought and its opposition to the real, individual world which is its object, — the chronic tendency, in a word, to raise the predicate into a subject, to place a corresponding thing by the side of the thought. But the lines of demarcation, the conditions of limitation, to which ideas owe their origin, have no counterpart in nature : and on the other hand it is the peculiarity of general ideas that in forming them we disregard the differences and demarcations of nature, that is to say, of individual existence, and consider everything rather from the point of view of universal qualities or predicates. By this road of generalisation, thought arrives at an ultimate idea in which predicates disappear and individual differences are absorbed, namely the idea of Being. When this idea comes to be realised, it seems to include all actual existence, and thus originates the idea of substance. It is however evident that nothing can be made of this concep- tion, for it is only in proportion as it becomes invested with predicates that it acquires reality and interest for the mind. Nevertheless this seems to be the point of contact between what is thought and what exists, and accordingly the misguided reasoning which imagines it can derive all knowledge from itself, often mystifies those who trust it with empty tautologies, such as, ' Being is ; what is, is, and it is so because so it is.' As soon as the reason has recourse to Being, as the necessary support of all predicates, it abdicates its sceptre in favour of another source of knowledge, 150 MODERN PHILOSOPHY. which is able to accept and deal with realities. For bare Being can give no food for thought; the ab- sence of predicates is the absence of any describable or cogitable nature, and here therefore the individual, the perfectly- determined but unknowable existence, enters again upon its rights. The individual alone really is. Hence the development of philosophy con- sists in a constant struggle between predicates and reality, or between thought and words, in so far as the latter assume to themselves equivalence with true, independent reality \ The energetic and victorious attack of Kant was the first which finally disposed of the idea of sub- stance ; but it should be remembered that Des- cartes' view of it marked an important stage upon the road to this goal. For while he assigned to it the widest predicates, which are taken for granted in ^ Tlie ontological proof of the existence of Grod, which occupied men's minds for so long, until its nullity was demonstrated by Kant, rests upon the delusion that existence in thought is identical with real existence, so that the latter may be derived from the former as its source. Substance, the Absolute, the ens absolute necessarium, the causa sui, cujus essentia involvlt existentiam, are all only so many vain attempts to found existence upon thought, and to dis- cover in the latter certain principles from which the world of reaUty may be deduced. These circular windings of human reason, tliis unprofitable trifling with its own creations, had been already condemned by Aristotle (Analyt. Post. ii. 7), to 6jj elvai oix ova-U ovdii/t, ' Being cannot constitute the essence of any existing thing.' Yet Aristotle himself believed that knowledge must start from Being or Substance. Hobbes seems to have been the first to protest energetically against this idea (Lev. cap. 46), and to have pointed to the root of the evil as lying in the confusion of words with things. ' Hobbes,' obsei'ves Lange, ' undoubtedly hits the right nail upon the head when he regards the hypostasising of the copula is as the source of countless absurdities. Aristotle made the word " Be " into a thing, as if there were some object in nature, designated by the word Being.' (Geschichte des Materialismus, i. 2 4 1 .) DESCARTES. 151 all tliought, it became evident which were the citadels against which attacks would have to be directed. The multiplicity of substances had only confused the mind and given occasion to unproductive struggles ; hut when all external phenomena were treated as modifications of the one substantia extensa, and all internal affections as modes of the one substantia cogitans, a regvdar campaign became strategically possible and secure of victory. Descartes himself betrays in one place his con- sciousness of the emptiness and want of matter in the bare idea of substance, as well as of the task imposed on his philosophy of reducing still further the number of ' things in themselves.' The passage may be quoted on account of the connection with the Kantian doctrine, which here appears with especial clearness : ' Thought and extension may be con- sidered as that which is constituted by the nature of thinking and material substance. . . . They ought then only to be conceived as the actual thinking and extended substance, i.e. only as mind and body^ ; in this way they are most clearly and correctly con- ceived. It is also easier to conceive extended or thinking substance than substance by itself without thought or extension. For it is somewhat difficult to separate the idea of substance from the ideas of thought and extension, as the distinction can only take place in thought, and an idea does not become clearer by having less included in it, but only by having what is included clearly distinguished from everything else.' ^ Kant says exactly the same, only in inverse order, i.e. mind and body are only ideas of the inward and the outward sense, and there- fore respectively, thought (or, according to Descartes, affections of consciousness) and extension. 152 MODERN PHILOSOPHY. ' Thought and extension may also be regarded as states of substance, in so far, that is to say, as the same mind may have different thoughts, and the same body, without changing its mass, may be vari- ously extended, sometimes more in length, sometimes more in breadth or depth, and again conversely. In this case they are modally different from the sub- stance, and can be conceived as distinctly as it can, provided only they are not regarded as substances, or things distinct from each other, but as different conditions of the same thing. For inasmuch as we consider them in the substances whose states they are, we distinguish them from those substances, and discern what they truly are. If, on the other hand, we attempted to consider them apart from the sub- stances in which they dwell, we should have to think of them as self-subsisting things and thus confound our ideas of states and substances.' (Princ. Phil. i. 63, 64.) We see in all this the widening of the gulf be- tween individual existences and universal predicates. In Spinoza it is completed, and all separate ex- istences are swallowed up in substance. Leibniz will make the attempt to reconcile the rights of the former with the postulates of reason, and Kant will finally show that the gulf follows inevit- ably from the nature of thought, that there is an absolute distinction between the worlds of thought and reality, and that the two qualities assumed by Descartes to be alone truly real, and which he there- fore exalted into substances, are after all only ideas of the subject, and therefore reducible to no other foundation than the Cartesian cogito. 5. We have above noticed Descartes' claim to re- cognition for having advocated tlie mathematical as DESCAETES. 153 the only true method of interpretation for the phe- nomena of the external world, which in all cases have to be reduced to quantitative differences. It is well known that Descartes, like Leibniz, was a dis- tinguished mathematician ; the foundation of ana- lytical geometry alone would have established his fame. It is not therefore surprising that his mind, when dissatisfied with the ]3rinciples of metaphysics, should have turned with longing to physics and physiology for the interpretation of the world-me- chanism, as it appeared in his grand and simple con- ception ^ Here stern necessity rules with unbroken sway, and the visible relationship of cause and effect. ^ Lange(Geschichte des Materialismus,!. 203)indeed maintains that Descartes attached less importance to the whole metaphysical theory usually associated with his nanie, than to his investigations in mathematics and natural science and his mechanical theory of natural processes. I must confess that I cannot share this opinion, which the passage quoted by Lange by no means seems to bear out. The passage in question (Discours de la M^thode, i. p. 191, Cousin) runs as follows : ' Although I was well pleased with my speculations, I believed that others had been not less well pleased with theirs. But as soon as I had attained some general notions in physics and on applying them to divers problems had observed how far they reached and how different they were from those commonly accepted, I thought I could not allow them to remain concealed, without a breach of that law which binds us to care for the general welfare of mankind so far as in us is. For these ideas have shown me the possibility of attaining opinions of great practical fruitfulness for the life of men, and that, instead of the speculative scholastic philo- sophy, a practical one may be established whereby the forces of fire, . water, air, the stars, the heavens, and all other bodies around us may be known as clearly as the work of our own artificers, so that we may be in a position to apply them, like these, to our own pur- poses, and in this way make ourselves lords and proprietors of nature.' What Descartes here announces in prophetic vein has been literally fulfilled. The high station now held by natural science. 154 MODEEN PHILOSOPHY. The time had not yet arrived for the idea of causa- tion to be tested and, together with the whole sum of mathematical knowledge, to be traced back to its real source. The idea of cause was looked upon as an unassailable possession, and the work of specu- lation seemed to be only to discover the corre- sponding members, and to connect each thing with its cause. We know that among the ancients Aristotle attempted to investigate and distinguish the various kinds of causes, bvit even he failed, as Schopenhauer' has pointed out, to reach a distinct consciousness of the important difference between material cause and intelligible reason. Aristotle however did good ser- vice by calling attention to the matter ; he con- stantly appeals to the nature of knowledge, and treats the theory of perception as an important part of the task of philosophy. His distinction between final and efficient causes {§vo rpowoi ri;? aiV/as' to ou eVe/ca Kai ro e^ ava^Krj<;) remains a valuable possession of human thought, and with it the knowledge that real necessitating belongs only to the latter of these. the vast transformation of practical life effected by its help, these only became possible through the strict application of the mechanical principle. And the latter is a philosophical idea, a fruit of Descartes' speculation. What he relies upon in this passage is the scriptural saying, ' By their fruits ye shall know them.' A philosophy which enables its adherents to solve large and difficult problems, estab- lishes thereby strong claims to acceptance as truth. He himself says of explanations derived from his own main principles : ' Cum ex- perientia maximam effectuum istorum partem certissimam esse arguat, causae a quibus illos elicio non tam iis i^rohandis quam explicandis inserviunt contraque ipsce ah illis -prohantur' (De Methodo, ad fin.) How vast has been the influence of Kant upon all the sciences I How little has the philosophising of Fichte, Schelling, Hegel, Herbart, and the rest produced except — empty words ! ^ Die vierfache Wurzel dee Satzes vom zureichenden Grund, p. 8. DESCAETES. 1 55 The multiplicity of the forms to which Aristotle ascribed reality, and especially his increasing pre- occupation with the organic world in which adap- tation is the rule, naturally contributed to facilitate the reflection. It seems as if the mathematico-mechanical treat- ment of the phenomenal world constrains the mind to confess : there is but one kind of cause, or like the Schoolmen : ' Non inquirimus an causa sit, quia nihil est per se notivis.' (Suarez.) This belongs to the special character of this source of knowledge, for in geometry, which starts with construction, knowledge and existence proceed at once from the same cause. The conception of the world as a single extended moving substance accustomed the mind to recognise everywhere similar compelling causes, ad- mitting of no further investigation. Fatal consequences followed from this promi- nent recognition of the mechanical necessity of all events, and the equally stringent intellectual neces- sity of mathematics, both for Descartes himself and Hs successors, especially Spinoza, as the various kinds of causes became confused and, e.g., reason was substituted for cause,^an error of which mimerous and striking examples have been taken by Schopen- hauer from Spinoza's works (loc. cit. p. 12-15). Hence too the same kind of necessity which prevails in mathematical thought is transferred to all other reasoning, and mathematical constructions are ap- phed to ideas that have a very different origin. An example is offered by the ' ontological proof and the ens necessario existens ; and as the keystone of his system, Spinoza asserts the mathematical necessity of events, because it follows from the idea of God that everything shovild necessarily happen as it does ] 56 MODERN PHILOSOPHY. happen, in the same way as it follows from the nature of a triangle that its corners should be equal to two right angles \ Hence too the attempt to clothe philosophical conclusions in mathematical forms which by no means suit them, an example set by Descartes in the Appendix to the Meditations, and followed, unfortunately, by Spinoza in his Ethics, where in- stead of allowing his ideas to express themselves Avith natural freedom, they are imprisoned in the apparatus of propositions, demonstrations, schoha, and corollaries. For the rest, here too Descartes abandoned further metaphysical research, or investigation of the data of consciousness, in favour of mathematical truths, which he held to be derived, as eternal truths, from the will of Grod : ' I say it would be as possible for God to cause it not to be true that the radii of a circle should be equal, as it was for him to create the world.' (Epist. i. no.) At this point however Spinoza, in open opposition to his predecessor, energetically defends the rights of reason, observing : ' It is held to be certain that the judgments of God altogether transcend human comprehension, and this would suffice to make truth eternally inaccessible to mankind, if another norm of truth were not provided for them by mathe- matics, which do not inquire after ends or pur- poses, but after the properties and characteristics of figures^.' This assumption of a single, universal, strict causal nexus, such as the phenomenal world suggests to the reflective mind, leads necessarily to a one-sided and erroneous conception of the intelligible principle in the world. For although in this also laws and internal " Spinoza, Eth. i. Prop. 17. schol. * lb. i. Prop. 36. DESCARTES. 157 necessity prevail, these are of a quite dijfferent kind from the necessity of nature. Every intellectual force struggles after freedom, and attains the same in proportion as it develops and spiritualises itself, and hence the highest kind of freedom known to us is that of human knowledge. The decisive principle then should have been found in this, and failing such verification, the natural consequence was a material- istic reaction, denying mind and conceding only natural necessity, and Spinoza's union of a causally determined substance at the same time material and intellectual. THE MATERIALISTIC TENDENCY. GASSENDI. HOBBES. Langb rightly indicates Gassendi and Hobbes as the revivers of the materialistic theory of the -uni- verse ^- These two men, of whom the first was to some extent an antagonist of Descartes, while the latter attached himself to Bacon, were yet powerfully in- fluenced by the new ideas, so that the materiahsm founded by them bears clearly the imprint of Car- tesian thought. The doctrines of Epikuros and Lucretius were brought up again by Gassendi (trimmed with a httle Christianity as the taste of the time and his status as a Catholic priest demanded) and opposed m their clear simplicity to Aristotle and the Schoolmen. Gassendi is the founder of the modern atomic theory. And wherein, we may enquire, does modern ma- terialism differ from the doctrines of Demokritos and Epikuros 1 To make this clear we must again revert to the materialism of antiquity and its relation to other systems, and especially to the opposition between Herakleitos and Demokritos. Herakleitos, as we have shown, dwells upon the etei-nal change and motion in the One, which under- lies all change {pTroKelixevov), and places the rational ' Gescliichte des Materialismus, i. p. 223 ff. GASSENDI. HOBBES. 1 59 principle of unity in the foreground, while to nature and experience he grants only this eternal flux or change. Demokritos, on the other hand, conceives the many, the infinity, multiplicity and variety, that is to say the material principle of nature, — as the essential. Philosophically or rationally speaking, the sameness of nature among the infinite and manifold atoms, that is to say, weight and form, out of which all the various appearances given by sense-perceptions arise, is the only thing explained. The individual is the most important postulate with Demokritos, while according to Herakleitos and the Eleatics it is entirely swallowed up by the One. It corresponds with this contrast that Demokritos was regarded by the ancients as a great jpolyhistor, and himself boasts of the extent of his travels and the range of his ex- perience \ while the significant saying, TroXvuaQlri voov ov SiSaa-K£i, is ascribed to Herakleitos. A similar contrast meets us in modern philosophy, between Spinoza, the retired hermit who plunges into the abysses of pure being and despises the world of ex- perience and empiricism, and Leibniz, the represen- tative of individualism, the travelled and accomplished man of the world, and a writer admired for his uni- versal genius. The first expression of the mechanical theory of nature is to be found, as before observed, in the doctrme of Demokritos. All that happens follows from the pressure and impact of moved, i.e. falling, atoms in the void. A strict, unbroken causal chain, together with the character of necessity, predomin- ates in this view, and hence in antiquity as now, the absolute necessarianism became associated with ^ 'Eyo) 8e tS>v kot (ixavTou Mpamav yr\v TrXfiorj/v €7ieiTXavrj(rdlir]V loro- peav TO lifiKiara. Clem. Alex. Strom, i. p. 304. l6o MODERN PHILOSOPHY. materialism as its especial characteristic, though at the same time it was regarded as an unworthy infringement of what we feel to be highest in our- selves — our freedom and our responsibility. It is however a rigidly logical consequence from the thought that recognises only one kind of cause. And it must not be forgotten that this same necessity gives its only firm foundation to the study of nature, which has always to deal with appearances, and that without it there could only be a wild dance of atoms, nowhere law and order. What stood in the way of the development of materialism in antiquity was that the doctrine of atoms was not connected with mathematics and so made to serve, as it is peculiarly adapted for doing, as the foundation of exact scientific research. The physical explanations of Demokritos and Epikuros are indeed often ingenious and acute, and remind us in many ways of modern views, but they remain in the region of hypotheses, because they despise or disregard observation and experiment and the nu- merical iDroportions to be learnt therefrom. Larger and smaller atoms, colfisions producing vortices of motion or motion in the line of impact, fine, smooth spiritual atoms present in the pores of all bodies and emitted from every surface, hook-shaped atoms that attach themselves and the like, these are the only principles of explanation by which it is sought to elicit something general, that is to say laws, from something individual, which atoms certainly must be considered to be. Thus it befell that the principle of necessity, in itself wholesome, precious, and rational, became trans- formed into another, seemingly opposite principle — that of chance. Demokritos' avajKii was at the GASSENDI. HOBBES. l6l same time Tv^n ^ And in fact this desjoerate union must be entered upon as long as numher fails to supply fixed points at which the individual can be brought under the general law, as long as falling atoms in continuous succession ofter — it is true a chain of causes, but — no general principle of explanation for the thread of causation. Like Tantalos, human reason in view of the rushing stream of phenomena could only say : ' I see indeed necessity, but for me it is always accidental ! ' As the product of remote antiquity this theory of atoms may claim our admixation, but important transformations awaited it at the hands of Baconian empiricism before it could come to life again after the deathlike rest of centuries, and then, m the mathe- matical era of Descartes, take its place in the front rank as an ally against the decaying Scholastic philosophy and its unfruitful trifling with ideas that exact science showed to be unfounded. Fertilised by experience, observation, and especially by the strict mathematical theory of Descartes, Atomism was destined to become the mould in which all vigorous speculation regarding the natural world was to be cast, and to render the most intricate, evanescent, almost imperceptible of phenomena at once clearly intelligible and comprehensible. The idea of material substance as laid down by Descartes is combined by Gassendi with the idea of atoms. They are the permanent element, the form of the changeable. Another great advance was made by Gassendi's identification of the atoms' weight ■ ^ By both he denies the existence of any other than efficient causes, i. a internal spiritual causation as well as final causes or ends. This should not be overlooked, as it is the ground of all our knowledge of nature. VOL. I. M 1 62 MODERN PHILOSOPHY. with their proper motion, so that the long-lived error of imponderability, which lasted even to our own day, was virtually confuted, the erroneous theory of matter found in Descartes was rectified, and the true essence of all material existence, motion, was clearly appre- hended. The atoms (created and set in motion by God) are the seed of all things, from them, by generation and destruction, everything has been formed and fashioned and still continues so to be. All growth and decay is but the union and separation of atoms. When a fagot is burnt, the aggregation of atoms is dissolved, and the atoms reappear in new forms and combinations as flame, smoke, ash, &c. It is plain that the preliminary conditions of a healthy system of physics and chemistry are contained in these views. It is also interesting to observe that Gassendi explained the fall of bodies by the earth's attraction, and yet, like Newton himself, held actio in distans to be impossible. He assumed in all such processes, as in magnetism &c., the necessary presence of some direct material intervention, a view which, however much it may run counter to contemporary opinion, will hereafter reveal its full truth and force in new and clearer ideas. And here, not to overlook a transcendental forecast of Gassendi, it may be observed that he regarded space and time as something distinct from matter, neither substance nor accident. When all things end, Space extends into infinity; Time was before all cieation, and flowed on then as now ^ Hobbes limited the scope of philosophy to the mathematico-physical interpretation of natural pro- cesses. For him the whole of philosophy consists in '' Lange, Gescliichte des Materialismus, i. 231. GASSENDI. HOBBES. 1 63 that one region of it, circumscribed and marked off by Descartes. According to Hobbes philosophy is, ' Knowledge of effects or phenomena derived from correct conclusions about their causes, or the same knowledge of causes derived from their observed effects. The aim of philosophy is to enable us to predict effects, so that we may be able to utilise them in life.' Lange ob- serves that this use of the word philosophy is so deeply rooted in Enghsh that it scarcely corresponds to what is understood by the name in other languages. A 'natural philosopher' has come to mean a student of experimental physics. Admirable in itself, and in full accord with this definition of philosophy as the mere interpretation of nature, is Hobbes's discernment of the infinite simphcity of the course of human reason. 'All reasoning is calculation, and all calculation is reducible to addition and subtraction.' In other words, for the human reason, all qualitative differences reduce themselves to quantitative ones, the question is everywhere only of a more or less ; a view agreeing exactly with that of Descartes. In connection with the above we may note his superiority to the danger of deception arising when the human reason is entangled in verbal fetters, as in the case quoted above (p. 150, note), where he attacks the Aristotehan Being. He says of the Co- pernican theory, the truth and importance of which he unreservedly admitted, that it had been strangled m antiquity in a noose of words. His utterances on the subject of speculative theology are also significant, and show that he had attained a clear view of the boundary line of transcendentalism. The connection between causes and effects leads M 2 164 MODERN PHILOSOPHY. necessarily to the recognition of a causa imma, an ultimate source of all motion, only the determination of its being remains altogether unthinkable, as it contradicts the nature of thought, which consists in addition and subtraction. At this point, where reason is arrested, religious faith assumes her rights. The onesidedness of materialism — that is to say the introduction of mechanical causation into regions where the mind has to be taken into account — re- appears plainly in the political theories of Hobbes, to which he attached the highest importance. One cannot but admire the iron consistency with which the theory of rigidly mechanical causation is applied, and the way in which the statics and dynamics of single forces alone are recognised in what we are accustomed to consider the highest intellectual or- ganisation — the body politic. The state arises immediately out of atomism. It is remarkable that Hobbes does not even concede to men the social impulses or instincts of ants, bees, &c., and so rejects the X^wov ttoXitikov of Aristotle. The state of nature for mankind is one of war. It seems as if he was dimly influenced by the thought that the rational principle, which obtains in the state, is something i&r higher than brute instinct, and that the absolute supremacy of the state, which is his ideal, is iudifierent to sympathy, but allots to each his right, which indeed only comes to be right because of the might behind it. For right and wrong, good and evil, virtue and vice have no meaning in themselves ; they originate in the political order, by the supreme will of the state. The Contrat social with him, as with Rousseau, supplies the original foundation for the state's constitution. Every man says to his neighbour, 'I convey to that man or this GASSENDT. HOBBES. 1 65 institution my rights of self-government, on condition that you also convey to it the same rights over yourself.' Thus the omnipotent authority of the state rises out of atomism ; the sole will that puts an end to the state of nature and establishes the kingdom of reason : ' hsec est generatio magni illius Leviathan, vel ut dignius loquar, mortalis Dei.' The state only punishes in order to maintain itself; religion or the fear of invisible powers are only political expedients. It must be confessed that such a positive relation- ship between might and right, in which everything which the state ordains is good, reasonable, and sacred, while criticism, in the name of higher prin- ciples, is rejected as injurious to the commonweal — this view agrees perfectly with the simple materialistic, mechanical theory of the universe in which also no- thing is recognised but the necessary working of real forces. And the system of Hobbes is certainly the most complete expression of rigorous materialism. Its dependence on Descartes appears in the fact that he discerned the incompleteness of the Baconian em- piricism, and by no means desired to restrict the activity of the mind to the mere analysis of sen- sible facts, but assumed, with Descartes, that the synthetic method should be applied in all cases, according the due place of honour to mathematics in the interpretation of nature. According to Hobbes, there is only one substance, namely matter ; an immaterial substance is a con- tradiction in terms. But matter as such, strictly speaking, does not exist, it is properly todies that exist ; realism and individualism thus meet, as they do in all genuine materialism. The idea of matter l66 MODERN PHILOSOPHY. is reached only by abstraction, it is only a name for the conception of bodies in general. The accidents of matter have no real existence, they are only the way in which bodies are conceived. The only reality is that which fills space and is coextensive with it. Extension and form are the only qualities without which we are unable to imagine bodies as existing ; all other accidents, such as motion, rest, colour, hard- ness and the rest, may change. Such change how- ever is only an alteration in the representation given by our senses, the quantum of the body continues unalterable. Here however we are constantly de- ceived by the counters of our verbal currency, which lead us to imagine that something quite different is before us, that from one thing another quite diflPerent has been produced. In fact all change is simply motion, or change of place among the component parts of the body. We have here the subjective representation ; the part of the subject in the perception of things is set forth strongly for the first time, an idea which, rendered possible by Descartes, leads through Locke to the final investigations of the Kantian Critik. And in this Hobbes not only rises above material- ism, he points, unconsciously, to a fixed point from whence it will hereafter be upheaved and destroyed. It is only necessary to bring together the various conclusions he maintains, and this will become ir- resistibly plain : ' Matter is nothing real, but a general notion derived from the principal qualities of bodies. The accidents do not belong to body as, such or in itself, they have no objective existence, but are the ways in which our senses are affected hy hodies. Even the ideas of substance and accident depend ultimately only on our arbitrary conception, GASSENDl. HOBBES. I67 and the linguistic determination of ideas, i.e. words : they are throughout relative. If we say, here a new thing has come into existence, we make use of the mental form of substance ; if, on the contrary, we judge that a pre-existing body has acquired a new quality, we still remain within the limits of the conception of accident.' These few sentences are enough to show the ad- mirable intellectual vigour of the English thinker and the extent to which he was in advance of his age. The knowledge of the dependence of thought on words, the importance of which is even stUl too generally neglected, would alone suffice to stamp him a great thinker. In all the sentences above quoted there are germs and intimations of the Kantian Idealism; it may even be said that the idea of substance was already partially divested of its reality and assigned to the sphere of the subject ; but Hobbes pursued his conquests no further, he thought that the task of philosophy was accomplished with the completeness of realism, and to him nothing was real but bodies and their motions. Thus, throughout his description of perception, he does not concern himself about what is internal in the process, i.e. the sensitive subject, his only object is to bring this branch of phenomena to take its place logically in his system of complete Realism. Hence he regards aU sensible perceptions as movements of infinitely small atoms that act upon the organs of sense and cause reaction in them. From this re- sistance there arises the disposition to conceive the object as something external, — ' ex ea readione ali- quamdiu durante ipsum existet phantasma, quod prop- ter conatum versus externa semper videtur tanquam I 68 MODERN PHILOSOPHY. aliquid situm extra organumi.' What a simple solu-- tion is offered here of the psychological problem of the externalisation of our mental representations, which in our time has been so obscured by mystical rhetoric ! Sensible qualities thus do not belong to things, i.e. bodies in themselves, but only exist sub- jectively. Light and sound are only motions of minute particles, which are perceived by us, and they can only be perceived by us because they pro- duce analogous movements in the particles of our organism, — for like can only act upon hke, and ob- jects in motion only upon moveable objects,— and it is only our resistance, reaction or counter movement which leads us to refei' the effect to an external object as its starting-point. It will be seen from this explanation how much Hobbes assigned to the thinking and feeling subject, viz. the sensible affections with their qualitative vari- ations, the apprehension of the different accidents of things, and of the difference between substance and accident, analj^sis and division, synthetic conclusions and conjunction ; — he passes by all this indifi'erently, and so far as appears treats it as the plainest thing in the world, while all the time he was on the verge of raising the question, how it comes to pass, for instance, that the subject takes the various accidents of things for essential qualities of things, if not indeed for things in themselves. This follows however from the rigorous carrying out of the one mechanical principle from which everything was to be derived and by which every- thing was to be explained. Only one kind of cause was recognised ; the old difference between the phe- nomenal and the real world of rational thought was ' De Corpore, iv. 25. GASSENDI. HOBBES. 1 69 again brought out, and the world of moveable matter — or rather of moving bodies — was declared to be the true real world, in so far as its determination was calculable arithmetically or mathematically, so that the highest product of reason was necessarily the self-knoivledc/e of inatter in motion. It is indubitable that the spirit of this doctrine is directly descended from Demokritos and Epikuros, but it is also certain that the spirit of Cartesianism has penetrated and fertilised it, so as to make it for the first time philosophically productive. Modern materialism is mathematical. While in antiquity mathematics were only applied to astro- nomy and mechanics proper, modern science has ex- tended this principle, as the only valid one, to all natural phenomena, since all have to solve mechan- ical problems ; so that the prophetic utterance of Descartes has been fulfilled, that the powers of re- mote celestial bodies and the mysteries of organic nature might be made as intelligible as the handi- work of mechanics and labourers. But meanwhile the law of necessity comes more and more into the foreground ; for in proportion as the hidden mysteries of nature are laid bare to the scientific eye and proved to be mathematically re- ducible to the simple element of mere forms of motion, in the same proportion the mind learns to recognise everywhere order and regularity, the supremacy of simple natural laws, which are the same in every time and place. It is thus enabled to extend the chain of causation forwards into the farthest corners of space, backwards into the remotest past, by the light of science to look forward into the events of future ages and to determine confidently what befell millions of years ago, before any human spirit breathed or 170 MODERN PHILOSOPHY. the foot of any rational being had trod the face of earth. Thus Demokritos' chance (Ti^x»;), by means of science and for scientific purposes, turns more and more clearly into necessity [avayKrij. But to see through this necessity and to discern that it lay in the nature of knowledge itself, this was reserved for the greatest of philosophers, for it re- quired the sagacity of a Kant. THE IDEALISTIC TENDENCY. GEULINX. MALEBBANCHE. BERKELEY. The starting-point of Cartesian philosophy was emphatically idealistic, its progress throughout real- istic. The transition from one to the other was accomplished — not to say necessitated — by means of the idea of God. The keys of true knowledge, true understanding of the universe, bestowed by the Deity upon mankind are the mternse veritates, and among these we must understand more especially mathematical knowledge. Only what man discerns in this way, and with this help dare et distinde intelligit, that alone bears the stamp of certainty, everything else is exposed to the illusions of sense and uncertainty. We have seen how materialism erected its system upon the base of certainty thus indicated by Des- cartes, without troubling itself further about the premisses from which this proof of certainty was de- rived by metaphysical reasoning. It might have been foreseen that other minds would occupy themselves anew with these premisses, and attempt a profounder and more consistent develop- ment of the foundations of the Cartesian system. Among these minds, Geulinx and Malebranche call principally for remark. One is accustomed to associate the name of Geu- linx with the thought of Occasionalism, the attempt to overcome, in a way more satisfactory to the human mind, the difficulties created by Descartes in his I 72 MODERN PHILOSOPHY. separation of mental and physical processes. For, notwithstanding the hypothesis of divine co-opera- tion, the mutual influence (mfluxus physicus) remains incomprehensible. Hence nothing remained except to make God the real author of all mental and bodily changes. On the occasion of a bodily process, God calls up an idea in my mind ; on the occasion of an act of will, God causes a corresponding movement in my body. But this interesting thinker really deserves most attention for his attempt to erect a new theory of knowledge on Cartesian principles, and to trace direct to the primitive spring of consciousness some things which Descartes had only thought it possible to explain by his theoiy of divine intervention^. Descartes had derived the truths of mathematics, upon which all clear and distinct knowledge rests, as Plato had derived his Ideas, wholly and solely from the will of God. The pure thought, made 2iossible by mathematical ideas, which was contrasted with sensible representations (imaginatio), makes use of these ideas because it has been so ordained by God. Even in regard to our most primary per- ceptions, e.g. that 2-1-3 = 5, we might become the victims of a supernatural delusion effected by a malignant spirit. In the same way that it had been objected against the reality of the Platonic ideas that they stand to each other in a relation of superiority and inferiority; in the same way Geulinx pointed out with regard to mathematical notions that they stood in an order of logical dependence, one of them being derived from another, Avhence it followed that all alike must be ^ Cf. Ed. Grimm, Arnold Geulinx' Erkenntnisstlieorie und Oc- casionalismus. Jena, 1875. GEULINX. MALEBRANCHE. BERKELEY. 173 deduced from the nature of our thought itself He instances several truths which could not be altered, in any way by the will of God, e.g. that A = A. Such truths are the foundation of all mathematical demonstration. To maintain the falsehood of the proposition 2 + 3 = 5 ^s to maintain that the meaning of two and three does not equal the meaning of 2 and 3, in other Avords, that A is not equal to A ; to admit the possibility of the radii of a circle not being equal is to admit that the straight line, by the revolution of which round one end the circle is formed, is not equal to itself Such truths as these are antecedent to the will of God ; they follow from his nature and his intellect. ' These truths,' says Geulinx, ' have their seat in our understanding, in so far as our understanding is in harmony with the divine, when we perceive them in God, and God after this manner.' Here plainly the origin of innate ideas is referred to the nature of the intellectual faculties, instead of to the will of God, which in itself is a material step in advance. In regard to the definition of matter also, Geulinx endeavoured to attain a higher degree of clearness than Descartes, whose weakness on this point has already been noticed. If space and matter are the same as to their essence (extension), how can they be distinguished by us 1 And how, on the other hand, can they be identical when space is infinite and indivi- sible and matter finite and divisible ? There must be a certain process of thought by which I produce the idea of matter, as a mode of the innate idea of space, from this idea itself. It is accomplished by a kind of abstraction, the nature of which Geulinx professes himself unable to define. Equally fine observations concerning the nature of 174 MODERN PHILOSOPHY. consciousness are to be found in Geulinx. All the definitions that may be given of mental processes do not deserve this name; they occur really by means of a figure, metaphor, or comparison. ' Quid sit amor, dici non debet; res ea nobis per conscientiam et intimam experientiam quam notissima est. Et id generatim obtinet in iis omnibus, quse ad cogitationes nostras, ad intellectum atque sensum, voluntatem item et animi affectus pertinent ; hsec enim omnia nobis, ut dixi, per conscientiam notissima sunt, nee possunt unquam definitione uUa declararii.' There is even in Geulinx a foreshadowing of the doctrine of Schopenhauer, that what appears in our imagination as external motion, is internally will : ' Hsec actio (qua membra nostri corporis movemus) nihil aliud est quam volitio, sentimus nempe et cla- rissime nobis conscii sumus, hoc solo membra nostra moveri (in quorum scilicet motibus imperium ha- bemus) quod moveri ea vehmus, licet interim ignari simus quo modo motus ille fiat.' Here occasionalism falls quite into the background, which elsewhere rests upon the erroneous assumption that an activity can only be exercised by one who discerns how it originated, upon which God is introduced as the summus opifex. Another very welcome feature is that Geulinx is the first among philosophers to feel called upon to vindicate the rights of the much contemned and abused senses, which had been degraded into mere nothingness, or at best into a handmaiden for the more distinguished rational cognition with which, as alone true and valid, it was always being con- trasted : ' There can be no doubt as to which is in itself the true world, the world of pure thought or ' Ed. Grimm, loc. cit. p. 14. GEULINX. MALEBEANCHE. BEEKELEY. 1 75 that of sensible perception. Which however is the more beautiful, the more honourable of the two ? I find few qualities in that world which, as the truly existing, gives occasion for the existence of the other. There is no change but that of motion. How far otherwise in the world of our senses ! Here I behold the light of the sun, the blue heaven's vault above me ; the flowers deck themselves out in aU the glorv of their varied colouring, I listen to the souo-hino- of the waves, the murmuring air, and clamour of the Storm. No doubt this world is the fairest, the most worthy of its divine author! We gaze with admira- tion upon the Deity, whose unspeakable magic takes occasion of our bodily motions to call up this world in us ; and we look up to him with stdl deeper admi- ration when we discern the spell running through this Grod-created nature. The world of ideas resembles a dry treatise ; the world of sense, on the contrary, a poem of phantasy^.' (Phys. Vera, Introd.) Still more important are the investigations initiated by Geulinx, in which, it may really be said, that he approaches the Kantian conception of the problem of knowledge. Amongst these must be placed first of all the question, whether there can be any know- ledge of things apart from the forms of our thought, that is to say, in Kantian phrase, any knowledge of things in themselves ? Such a question, uttered for the first time, . breathes the whole spirit of modern philosophy. GeuHnx's answer to the question runs as follows : ' When we think and judge — for judg- ment is the soul of thought — we use a subject and a predicate. The subject must be conceived, by means of a fundamental internal faculty of our mind, which cannot be further defined, as a Being (ens). I conceive ^ Ed. Grimm, loc. cit. p. 48. 176 MODERN PHILOSOPHY. the thing thus contemplated as one, by including all its parts, and excluding the thing itself from everything else. This unity does not belong to, e.g. a table as it is in itself, but is completed only in our mind (totatio). We must further ascribe the predi- cates to the subject, i. e. we must declare something about it. Every subject only becomes a subject when it is conceived as being (ens). This is the nota sub- jedi. When we add this note to an adjective, it becomes a subject (the good, the sweet) : when we subtract this note from a substantive, it becomes a predicate (the man is a judge). The great question concerning substance and accident thus reduces itself to the grammatical distinction between substantive and adjective.' Such a sense of the dependence of our thought upon the forms of speech betrays a pro- found insight into the nature of knowledge and perception. ' But how does it happen,' he asks further, ' that certain qualities are chiefly indicated by substantives and others by adjectives ? The distinction seems to have arisen because certain things appeared perma- nent and durable, such as bodies, and others again more fugitive and variable, such as heat and cold, light and darkness, colour and sound. Out of the durable ones in the first instance substantives and substances were formed, and out of the fusitive and changeable ones adjectives or accidents. But the dis- tinction itself proceeds wholly from sensible percep- tion, by which the human mind is almost always governed, so that the distinction is accepted in our thought as something actually existing. Thus nothing appears more permanent to our sensible perceptions than the body; the mind however altogether eludes theu- glance. And therefore we need not be surprised GEULINX. MALEBRAlSrCHE. BERKELEY. 1 77 that there have been people who held the soul to be an accident of the body, and characterised man as a cor])us animatum rationale^.' Credit has already been given to Hobbes for having divined that the true source and form of thought was to be found in language, and the same praise, only in yet higher measure, must be conceded to Geulinx. It was reserved for the present age and the rapid strides which comparative philology has made in it to discover the immeasurable importance of the study of language to all sound philosophy. But honour and admiration are none the less due to the first heralds of the scarcely dawning day. Greulinx made use of the new knowledge to drive the countless categories and petrified notions of scholasticism out of the field. The two real forms of thought, to which everything is referred, are those of Substantive and Adjective, or Subject and Predi- cate. He says in express terms that his opponents (the Aristotelians) were indignant ' at seeing their highly praised metaphysical chrysalis appear in its perfect form as pure Grammar. But they need not be ashamed of this science ; indeed there is nothing more worthy of a philosopher than this same grammar, for it is the science of the most primary and universal forms of thought ^.' By the help of these premises, the main question, as to the possibility of a knowledge external to the forms of thought, answers itself Knowledge neces- sarily declares something about things, and therefore must be clothed in words. But as soon as the under- standing conceives any object as a something, it has already invested it with the form of its own thought, that of the subject. The predicate and copula are ' Ed. Grimm, loo. cit. p. 61. ^ Id., loc. cit. p. 63. VOL. I. N 178 MODERN PHILOSOPHY. introduced in the same way, and tlius the forms of two mental activities are apphed to the thing. In other words, no knowledge of things is possible out- side the forms of thought. Keason is superior to sense. Knowledge of things, apart from sensible perception, only becomes possible by means of a higher faculty, which brmgs them be- fore us, namely, reason. If there were a stiU higher faculty than this, we could reject all rational as well as sensible knowledge and rely only upon it. But no such faculty exists, and we must therefore con- ceive things under the mental forms of our reason ; for things in themselves can never become the objects of cognition. This view itself is valuable, and will preserve us from many errors. If I see a stick in water as bent, there is no error about the fact ; error only begins when I maintain that the external reality corresponds to my sensible perception. And similarly, men are not in error so long as they conceive things in the forms of human thought, but only when they ascribe these same forms to the things in themselves. To conceive the things under these forms is a necessity which the wisest cannot escape, but he may refrain from judging the forms to pertain to the things in themselves, and herein indeed his wisdom consists *. We see in all this a worthy prelude to the Kantian Critik of pure Eeason ; the same clearness and caution, the same method, the same insight that all human truth and certainty must be derived from reason, that the task of philosophy is to establish the limiting conditions of this faculty, and that human knowledge cannot attain to the discernment of things in them- selves. ^ Ed. Grimm, loc. cit. p. 66. GEULINX. MALEBRANCHE. BEKKELEY. 1 79 Geulinx restricts his criticism to the forms of judg- ment, wliich in tliemselves are empty and insignifi- cant in his eyes ; and side by side with them he allows innate ideas to subsist, treating these through- out as substantial. And hence he repeatedly maintains, that although we can only know in accordance with the forms of thought, and must translate everything into these forms, still body and mind are self-sub- sisting objects, or substances: — a contention which enables us to measure the depth of the abyss into which Kant still had to plunge to rescue truth. Malebranche may be dealt with more briefly. His penetrating mind too felt oppressed by the unmi- tigated opposition of the two substances as presented by Descartes. He too rejected as inconceivable the influxus physicus, since mind could never act on matter, nor matter on mind. Schopenhauer however is right in observing that he forgot that the influxus ^Jiysicus had already been assumed in the creation and government of the material world by a spiritual God. Malebranche's attempt to reconcile the two oppo- sites is inspired rather by the spirit of Platonism than that of mathematical science. He enquires, how the mind attains to ideas of material things and of an external world existing independently of itself 1 For it is certain that what is conceived by the intellectual nature must itself be of a spiritual kind, belonging to the forms of consciousness : the material can never act on the immaterial. But what causes the soul to ascribe reality to ideas, or reality to enter the soul in the form of ideas 1 The view is here clearly that of Plato, combined with the Cartesian limita- tion to subjective consciousness and the two sole substances. Malebranche seeks his solution by regarding the N 2 l8o MODERN PHILOSOPHY. suhstantia cogitans as a whole, apart from its connec- tion with the material world ; for as the suhstantia extensa subsists throughout space in a constant, inde- structible relationship of material interaction, in the same way an inward, uninterrupted connection of cause and effect binds all intelligences to the causa lorima, i. e. the Deity. The Deity then is the Abso- lute, Intellectual Substance, the thinking Principle which bears and comprehends all ideas within itself, and beholds and knows all things as they essentially are. The human soul only attains through this me- dium to the knowledge of things, and so to the conception of an external world. ' We see everything in God : God is the place of spirits."" We see here not only the affinity with Plato, but also a sincere attempt to reach a logical and satis- factory solution by starting from the Cartesian pre- mises. At the same lime, in a way rather dangerous to the Christian opinions of the author, the indi- viduality of spirits is swallowed up in the absolute, intellectual abyss of the Godhead ; the path he has entered upon could only lead, if followed further, to Pantheism. In general it may be observed that Pantheism was not easily avoidable according to the principles laid down by Descartes. In proportion as the idea of substance was extended and made more and more to include all reality, it attained to a unity of nature, which, though it did not indeed exclude the mutual determination of parts, postulated a complete un- conditionedness for the whole, from whence every- thing else was to result as from the causa ^rima. The view of Malebranche recurs again in the doc- trine of Spinoza, and there, as we shall see, leads that generally profound thinker into a labyrinth, where GEULINX. MALEBRANCHE. BERKELEY. I Si he wanders in obscurity without finding any outlet for himself. Thus he says, in the fifth proposition of the second part of the Ethics, that the formal ex- istence of ideas has its cause in God alone in so far as his nature is intellectual, but not in so far as he is conceived under any other attribute. ' That is to say/ he adds explanatorily, 'both the ideas of the divine attributes, and those of individual things, are caused, not by their objects, or the things represented, but only by God in so far as he is an intellectual being.' This is quite the course of thought seen in Malebranche : ' Nous voyons tout en Dieu.' The efforts of the two above-named thinkers to reconcile the idealistic and realistic points of view broke down in the same way as Descartes' explanation. There is no method by which we can combine in the idea at once all that it has been assumed as exclud- ing and as containing ; but there always remains as a last resource an appeal to the Deity by whose intervention all impossibilities are rendered possi- ble. Both Geulinx and Malebranche endeavoured so far as possible to lighten the labours of Divinity, to leave as few impossibilities as possible to be so accounted for, and accordingly to allow more for human consciousness and intelligence. They were in this more consistent Cartesians than Descartes himself, and pursued the road he had so boldly entered upon for another long stage in advance, before they too gave way and began to resort to a supernatural explanation, of the connection between the material and the immaterial world. The road of both was that of Idealism, but they did not pursue it to the end. This was reserved for another thinker, whose work must be noticed here because of its relation to theirs, although he belongs to a later date 1 82 MODERIT PHILOSOPHY. than Spinoza, Locke, and Leibniz, and was to a certain extent influenced by their speculations. This thinker is Bishop Berkeley (1684^1753). Schopenhauer observes 1; 'Berkeley, although later, and knowing Locke, followed the track of the Cartesians to its furthest logical conclusion, and so became the author of the only real and true sj'stem of Idealism, which maintains that the ex- tended matter filling space, i. e. the sensible world in general, can have no existence as such except in our mind, and that it is absurd, indeed contradictory, to ascribe to it as such an existence outside our thought and independent of the knowing subject, and consequently to assume the existence of a self- subsisting matter. This profound and just notion constitutes the sum and substance of his philosophy. He has hit upon and clearly distmguished the ideal element, but the real escaped him, indeed he con- cerned himself little about it, and only offers occasional, partial, and incomplete utterances on this subject. The will and omnipotence of God is the direct cause of all the phenomena of the perceptible world; that is to say, the real existence of all the objects of our thought is attributable to knowing and willing beings only, such as we are ourselves, and therefore these together with God make up reality. They are spirits, that is to say, knowing and willing beings ; for he maintains will and knowledge to be inseparable. He has also in common with his predecessors the belief that God is better known than the apparent world, so that any reference to him appears as an explanation. It may be that his clerical and episcopal status imposed too heavy shackles and limited him to a narrow range of thought, beyond which he was '■ Parerga und Paralipomena, i. p. 1 4. GEULINX. MALEBRANCHE. BERKELEY. 1 83 on no account to stray. Hence he could make no further way, and the true and the false had to keep house together in his brain as best they might. This applies indeed to the works of all these philosophers, with the exception of Spinoza.' The matter may also be stated in the following way: According to Descartes, the highest a priori idea is that of being or substance. He did not originate the contrast between thought and being, whence the salutary distinction between objective and subjective existence has been derived, but he dwells only on that between thought or consciousness and material extension. He attributed being equally to both, hence his substantia cogitans and extensa. His two successors, Geulinx and Malebranche, remained at the same standpoint. Berkeley was the first to doubt the reality of extended, material substance, and indeed to transfer all things into the realm of mind, and to explain all ideas of external objects as products or even functions of the latter. And this alone is true idealism, the logical development of the fundamental truth of Cartesianism ; and at the same time the overthrow of Cartesian dualism, by the substitution of Henism — the assumption of but one kind of substance. The salutary effects of the Berkeleyan train of thought, together with its weaknesses and onesided- ness, may be easUy summed up. Its merits are: I. That the idea of substance— at least on one side — was completely done away with, and the fallaciousness of the inference was shown, which concludes from affections and representations of consciousness to actual things existing outside consciousness, and then attributes equal reahty to these. The cumbrous legacy of scholasticism, the idea of substance, with 184 MODEEN PHILOSOPHY. which Descartes and his successors were weighted, was at least diminished by half. 2. Chief stress was laid upon the point towards which modern philosophy was first directed by Cartesian insight, and from whence alone sure results are found attainable, namely consciousness, or the thinking mind. A criticism of the processes of consciousness might lead ultimately to an ex- planation of how and by what right this consciousness assumed the existence at the same time of its own ideas and of external objects corresponding to them. And from this point of view Berkeley also may be reckoned among the precursors of Kant. But the onesidedness of this theory is at least equally self-evident. When Berkeley makes con- sciousness create everything out of itself, and in a certain sense, spin eveiything out of its own sub- stance, the gates are shut upon experience. The arrowth and genesis of ideas, which contradict them- selves, are in conflict with and eventually neutralise each other, and yet all lay claim to correspond more or less with an existing reality outside ourselves, — all this becomes wholly incomprehensible and tmintelli- gible. Berkeley, like all his predecessors, is obliged to take refuge with the Deity, who is the true author of all mental processes, by which these ideas are called up in our minds and made to follow each other in orderly sequence. The only difference between his doctrine and that of Geulinx and Malebranche is that, according to the latter, the material world, which by the divine co-operation we think of as real, does also actually and really exist, while accordingly to Berkeley it is a mere phantasm, f ' Berkeley's theory is the direct 'opposite of ma- terialism. As the latter assumes matter to be the only GEULINX. MALEBBANCHE. BERKELEY. 1 85 self-subsisting reality, so Berkeley assumes mind or consciousness. The being of matter consists only in its being presented in thought. Esse = percipi. And it is not to be denied that if the choice lay only between these two extremes, the spirit of Cartesianism and of modern philosophy would allow the claims of the latter view to the larger share of truth, for con- sciousness alone is directly given and certain. And yet Berkeley too is unfaithful to the trvie starting-point of the Cartesian philosophy, which consists in the conscious Ego, the thinking subject. The idea of substance, from which he has freed him- self on the material side, still holds him prisoner upon the other, immaterial side, and forces him into illogical conclusions. For if true being consists only in being perceived, by what right can m}^ con- sciousness assume the existence of beings distinct from myself, but able like me to think, imagine, and will 1 How can I ascribe actual reality to them, or even to the Deity, since I have no assurance of their existence save from my own thought and imagination. Must we not, with strict remorseless logic, apply also to the existence of these spiritual beings the doctrine that the ideas of the conscious subject have no reality outside his consciousness 1 Must not the well-known utterance of the mystic poet be recognised as full and valid truth : — 'Ich weiss, class ohne mioh Gott nicht ein Nu kann leben, Werd, ich zu nicht, er muss von Noth den Geist aufgeben.' Angblds Silbsius. After all, Berkeley's chief merit consists in his having been the first to give utterance to the funda- mental truth of idealism, which Schopenhauer, at the beginning of his chief work, has formulated as follows : ' The world is my idea — this is a truth 1 86 MODERN PHILOSOPHY. which holds good of every living and knowing being, although man alone is able to reach a reflective abstract consciousness of it : and if he really does so, he has already attained philosophical discretion. It will then be clear to him that he knows no sun, no earth, only an eye which sees the sun, a hand which feels the earth ; that the world which surrounds him is only there as thought, that is to say, only in re- lation to something else, namely, the thinker, he him- self If there is any truth that may be enunciated a priori it is this. . . . The subdivision into object and subject is the only form under which any kind of mental representation whatsoever, abstract or intuitive, pure or empirical, is generally possible or thinkable. No truth is therefore more certain, more independent of any others, and less in need of demonstration, than this : that everything which exists for our perception, .and therefore the whole world, is only object in relation to the subject, in- tuition in relation to the intuitive mind, in one word, Idea.' ' This truth is in no way new. It was involved in the sceptical considerations from which Descartes started. But Berkeley was the first to give it de- cided utterance ; he has won thereby undying fame in philosophy, even though the rest of his doctrine cannot be maintained ^' ^ Schopenhauer, Welt als Wille iind Vorstellung, i. p. i. THE MONISTIC TENDENCY. SPINOZA (1632—1677). We have seen liow the iiDreconciled and irrecon- cilable elements in the Cartesian dualism ended in leading by a double road to Henism, according to which either matter or mind, substantia extensa or substantia eogitans, had the right to existence alone conceded it, while the other side was either ignored or treated with indifference, as for instance when the mind was regarded as an accidental affec- tion of matter, or the material world as the product of the intelligent consciousness. Materialism reposed contentedly upon the couch prepared for it by Descartes, a strictly causal, me- chanical theory of the universe ; and its rest was untroubled by the alarming certainty that matter, extension, number, cause, in short the whole real and palpable external world, necessarily presupposed a sensitive and intelligent consciousness, without which it could have no existence for mankind. As soon as this truth began to force itself irre- sistibly on the minds of serious and conscientious thinkers, they sought with despairing energy to find in their one acknowledged principle some point d'appici towards the other side, an endeavour in which they naturally shared the fate of the arch- har Miinchhausen, when he tried to lift himself and his horse out of the morass by his own pigtail. Among these impossible attempts may be reckoned MODERN PHILOSOPHY. the problem proposed by Hobbes (simply repeated with variations by Lange^) and claaracterised by him as one of the highest and most important that can occupy the human intelligence, 'What kind of motion can it be that produces the feeling and imagination of living creatures?' One might as well ask: 'How ^ Geschiclite des Mateiialismus,i. 237. Cf.the passage quoted above, p. 41, note. Whenever Lange gives expression to the opinion that the processes of thought and sensation ' may be explained as a special occurrence arising out of universal mechanical natural necessity,' he falls into that same materialistic self-deception. It must how- ever be acknowledged that in many, nay in most passages, this excellent writer fully recognises the infinite difficulty of the firoblem, and points to the direction in which the solution must actually be sought. Resolution to follow this path indeed failed him. Thus when speaking in blame of Aristotle, who elevated his forms in transcendental fashion into causes of motion, and thus struck a fatal blow at the root of the study of nature, while Demokritos had been on his guard against following these clues into further metaphysical depths, Lange observes : ' Here the Kantian Critik of Eeason was needed, to cast a first faint ray of light (!) into the abysses of a secret, which is still, after all the progress of natural sciences, as piofound to-day as it was in the age of Demokritos.' (lb. i. p. 19.) Another crude expression of the materialistic pre- judice is to be found in Dubois-B,eymond's ' Grenzen des Naturer- kennens,' p. 34: ' The theory of descent, taken together with that of natural selection, forces the idea upon the student, that the soul has come into existence as the gradual product of certain material com- binations' To exhibit still more cleaily the helplessness of modern science in the face of the dualism which seems innate in human natuie, it may be noted that Ueberweg is driven to the assumption that ' the law of the conservation of force will reappear in psychical processes,' until at last in a letter to Lange he resigned himself to the despairing confession : ' If you can help me out of the strait I shall be your debtor indeed ; but it will not be enough for you to show me the improbability of what I myself see to be very little probable in itself, but you must open some other outlook to me, that shall at least strike me as moderately plautible. / Jcnow no such.' (Lange, loc. cit. ii. p. 518.) SPINOZA. mucli thouglit and imagination will suffice to set a mill-wheel or a steam-engine in motion V Spiritualism too needed equally to be inspired Ly a stronger faith than that which removes mountains, in order, after scornfully rejecting 'that stupid thoughtless somewhat' known as matter into the realm of nothingness, calmly to resist the stormy force with which the outer world proclaims its ex- istence every second, and to transform the whole content of knowledge into an airy appearance, or a mere dream with which a cunning magician mocks our slumbers. But the very stress of compulsion, which drove such distinguished men to such extravagant ex- tremes, shows of itself the enormous difficulty and perplexity of the problem, and should lead us to more modest criticism of the Cartesian dualism than is usually indulged in. There was only one other path left open, and this was trodden by Spinoza, that namely of endeavouring to restore to its original natural unity what had been separated in thought. In this human reason returned to its first instinctive conviction, but the newly-won truth was really something quite different. For there are always three stages visible in the progress of human reason, from confounding to distinguishing, from distinguishing to comparing, and from com- parison to the establishment of a higher unity. On this subject Geiger observes^: — ' The human reason pursues its course forwards and sideways, and often returns upon the point from whence it started, only with a change : so that when its action seems to have become the same as before, ' Ursprung und Entwickelung der menschliclien Sprache und Vernunft, i. p. 91. I90 MODERN PHILOSOPHY. there is a difference in its mode of j^erforming the same operation. Man strides from belief through doubt to knowledge, and often after a long course of experience he reaches the goal of convictions which were taken for granted from the first by the unthinking. And yet this circviitous course cannot be looked upon as superfluous, for its accomplish- ment leaves the mind enriched with the boon of consciousness.' Thus from the earliest times mind and body were held to be one and the same, and if the sight of death made it necessary to assume a separation, the surviving soul was still imagined with a new kind of material existence, a body only of a finer and more airy substance, in which the spirit dwelt as before, aud wrought good or evil to those left behind. Hence Ancestor or Manes worship. The busy and fertile fancy of the earliest races was also penetrated with the conviction, that all the powers of nature, which we now class as soulless, such as clouds, storms, rivers, sea and sky, were all living, conscious beings like ourselves, only immortal and furnished with superior might : hence mythology and polytheism. But it was another and far harder task to reunite what had been sharply separated and distinguished by Descartes, in conformity with the general opinion of many centuries. Spinoza himself indeed was not altogether without precursors, and among these has rightly been reckoned the profound Pantheist, Giordano Bruno (b. 1550, burnt 1600), who in high poetic flights divines again a soul within the universe, and instead of regarding matter as something merely passive, or in Aristotehan phrase, as the bare possibility of becoming, maintains rather that everything proceeds from it and is pro- SPINOZA. 191 duced by separation and development : ' and there- fore matter is not destitute of the forms, but, on the contrary, contains them all ; and as it unfolds what has secretly been borne within it, it appears in truth as the whole of nature and the mother of all that lives.' But we must not forget the distance from these essays in which emancipated thought first tried its wings, under the stimulus of the Copernican theory of the universe, between the profoundest conjectures of a Giordano Bruno, a Campanella or the like, and the pupil of Descartes, ti'ained in the strictest dis- cipline of mathematical thought, and fully conscious of the difficulty of the problem before him ; recog- nising on the one hand the strict mechanical depend- ence or irrevocable antecedents of all material change, and on the other the irreconcilability of the latter with that other kind of causation which we meet with in our own consciousness, and which is more certain, that is to say more primitive, than any other. No doubt Spinoza would have remained faithful to Cartesian dualism but for the logical necessity which compelled him to perceive a gap in his master's system, an internal contradiction, a false deduction from imper- fectly defined or conceived ideas. This, together with the revolt of those secret convictions which rest upon the common sense of mankind and for which a philosophical foundation had been laid by the Humanists, and even some free-thinkers among the Schoolmen, e.g. Pomponatius, who denied the immortality of the soul and disclosed the incon- sistency between the idea of the divine omnipotence and human free-will, — this all combined to show him the urgent need for some correction of or some point of view beyond the former doctrine. 192 MODERN PHILOSOPHY. It is again the idea of substance from Avhich every- thing is to depart and into which everything is to revert. As we see, this idea embraces, according to Descartes, the whole of existence ; and by a fallacy, a violent transition from the imagined to the actual, the character of necessary existence is added to it. Now Spinoza raises no objection to tMs necessity, on the contrary, he accepts it as a starting-point, ob- serving : ' Per substantiam intelligo id quod in se est et per se concipitur,' after this idea has already been introduced as causa sui; of which it is said, ' per causam sui intelligo id cujus essentia involvit existentiam ; sive id cujus natura non potest concipi nisi existens.' But Descartes, while including all existence under the idea of substance, at the same time distinguished two kinds of existences, to both of which the honour- able name of substance was to be accorded. The philosophical conscience of Spinoza revolted against this. It is impossible, he held, that existence should be one, and then again at the same time two ; there can only be one substance, which is by nature eternal, infinite, indivisible, and furnished with infinite per- fections, i.e. qualities or attributes. This substance he too calls Deus, — though most frequently with the addition sive natura, — and of this it is said, 'Preeter Deum nulla dari, neque concipi potest substantia' (Eth. i. Prop. 14); and again, ' Quidquid est in Deo est et nihil sine Deo esse neque concipi potest' (Prop. 1 5) . This God is the immanent cause of all things ; his existence and his essence are iiniim et idem (Prop. 20). Philosophical speculation is here straining towards the same heights as the Eleatics sought for, the eternal, unchangeable one (ei' kuI vrar). But here too SPINOZA. 193 there is a wide difference. The Eleatics acknow- ledged unity as the rational principle, but were unable to proceed from it to the manifoldness of the world, and hence the phenomenal world was dis- posed of offhand by Parmenides as the 'not-being,' while Zeno pointed out the inner contradiction into which reason fell in conceding reality to the many. Spinoza's substance was the all-embracing, all-com- prehending reality, in which all single existences find their place ^ , and may be conceived as grasped in connection with the whole by its necessity and rationality, while apart from this connection, con- sidered as existing in themselves, they can only be the objects of erroneous, i. e. imperfect, incomplete perception. Imagination is the greatest foe to true knowledge ; for while we imagine single things, characterise them with words, and withdraw them by abstraction from their place in the great general order, we bestow the character of substance upon accidents, and sever and divide what in nature is undivided and con- nected. We can only attain to true knowledge by conceiving the universe as one, and considering it as existing, not in time but suh specie leternitatis. Descartes' mistake was to bestow the character of self-subsistence upon the two predicates, thought and extension. This error revenged itself by making the union or interaction of the two substances perma- nently impossible and inexplicable. In fact the two predicates, extension and thought, are only two attri- butes of one and the same substance. The attributes are the eternal, immutable qualities of substance, ' This appears clearly from Eth. v. 24 : ' Quo magis res singulares intelligimus, eo magis Deum intelligimus.' VOL I. O 194 MODERN PHILOSOPHY. which exjjerience does not make known to us, but which themselves underhe all our experience ^. Medi- tation upon these attributes leads to true, pure know- ledge, which consists in this, that everything is brought into connection with the prime source of all existence, that is to say, with God, in whom all things live and move and have their being. Human thought approaches to perfection in proportion as it becomes a partaker in the divine, towards which its upward struggles are directed. All separate exist- ences, mankind, individual men, are only modifications of the infinite substance, comparable to the curling waves, which form and vanish again upon the surface of the ocean. AU separate existences, alike material or spiritual, are held together by the rigid iion bond of causahty. It is only in the All that freedom and necessity are the same, for God creates and causes all things ex necessitate naturae suse, for he is infinite, untrammelled, and hence cannot be determined by anything else to act or work. Omnis determinatio est negatio. The great problem of matter and mind is thus solved by Spinoza in the simplest, the most startlingly simple way, to which the saying simplex sigillum veri is surely applicable. As Goethe, Spinoza's greatest disciple, says. There is no mind withoiit body, no body without mind. Both are one, they are a Monon, which our thought grasps by abstraction now on one side, now on the other, modo sub attributo extensionis, ^ ' Nulla experientia id (quod ad essentiam pertinet) unquam nos edocere poteiit. Nam experientia nullas rerum essentias docet, sed summum, quod eflficere potest, est mentem nostram determinare, ut circa certas tantum essentias cogitet. Quare, cum existentia at- tributorum ab eorum essentia non diflferat, earn nulla experientia poterimus assequi.' Spinoza, Epistolse, xxviii. SPINOZA. 195 modo cogitationis ; and then because they are denoted by different words, it is hastily assumed that different independent beings exist corresponding to their names. In reahty instead of one matter and one mind, there is a single Something, which is both at once. Each taken in itself is imperfect : the two qualities are distinguishable but not separable. A causal nexus must not however be assumed, con- necting the two attributes. We should not ask if and how thought can act upon the body or the body on thought ; in the world of extension everything is accomplished in accordance with stern, mechanical laws, while the mind proceeds only by the inward linking of ideas : only because the two worlds are one and the same, there is a mental change cor- responding to every material one, and conversely. Hence the fundamental perversity of such questions as are propounded as the greatest problems in one- sided henistic systems, e. g. How can mind and con- sciousness originate out of bodily modifications 'i How can mind produce out of itself our ideas of bodies and the things themselves ? In relation to man the essentials of the monistic view may be formulated as follows. Our body presents itself to us in twofold fashion ; first as external, material, an object among objects, and then again as consciousness, feeling, will (all these expressions must be used together to characterise the nature of mind), or in a word as in- ternal. It is only himself that man knows immediately in this twofold character : everything else in nature appears before him as external, as object. But he soon acquires, by intercourse with his kind, the obser- vation of kindred lives, and finally, from irresistible rational grounds, the conviction that there is life in the whole of nature, that this inward property does not 2 196 MODERN PHILOSOPHY. belong to himself alone, but that, in greater or less de- gree, aU other beings participate in the same. These degrees of consciousness constitute the degrees in the variety of things, and supply the standard of ]Derfection clearly laid down in Spinoza's words : ' plus realitatis habere, i. e. plus agere, minus pati.' Schopenhauer himself was compelled to recognise the latter truth, although with him consciousness was only a subordinate variety of animal life, subject to the wholly unconscious Will. He says in the Pa- rerga 1, ' Thus the degree of clearness in consciousness, or of reflection, may be regarded as degrees of reality in existence. But even in the human race itself these degrees of reflection or clear consciousness of personal or other existence are very numerous and gradually shaded. It must be admitted that some men have tenfold the intensity of being of others, m-e ten times as much. . . The majority of men only perceive things as they are in relation to the will of the moment, they do not reflect iipon the sequence and coherence in their own existence, let alone that of existence in general ; in a certain sense they exist without being aware of it. Hence the existence of the thoughtless proletaire or slave, who hves from day to day, ap- proaches materially nearer to that of brutes, who are altogether restricted to the present, than our own does. Or we may compare it with the hfe of a cautious, intelligent merchant, who spends his time in speculation, in the careful execution of maturely considered plans, who founds a family, provides for his wife, children, and posterity, and moreover takes an active part in the affairs of the commonwealth. Obviously such a man possesses far more of conscious existence than the former, that is to say his existence ^ Vol. ii. p. 630. SPINOZA. 197 has a liigher degree of reality. And if we turn now to the student who investigates, let us say, the history of the past, we find him possessing a consciousness of existence as a whole which extends beyond his own person and includes the course of the universe.' All this is implied in Spmoza's words : ' Quo unaquseque res plus perfectionis {or realitatis) habet, eo magis agit et minus patitur at contra quo magis agit, eo perfectior est.' Everything seemed to show that the monistic theory of the universe, which first received its clear expression in the West at the hands of Spinoza (though in the East it had spread long before), would soon become generally prevalent, while dualism would be wrecked on the rock of its own inconsistency and irreconcilableness with science, and Henism, which in our day means practically materialism, would be con- demned by its obvious incompleteness, and denial of the noblest and most essential qualities of humanity. The only difiiculty still left for monism to surmount lies in the inveterate prejudice, which has grown in the course of ages into a second nature, according to which we distinguish between an animate and in- animate world, or even think of matter as something purely passive. We can only clearly and completely comprehend the nature of any being, by endeavouring to understand, not merely its outside, or the way in which it presents itself to our imagination as an ob- ject in space, but also its inner nature. But at this point we are met by the difiSculty that the word inner, which is derived, like all our notions, from the ex- ternal world, and only applied metaphorically to the mind, is usually misunderstood by those votaries of natural science whose only object of investigation is this phenomenal world, i.e. matter ; for they imagine 1 98 MODERN PHILOSOPHY. themselves to penetrate by these processes into the very heart of organic things, and do not consider that aH the while they are still only dealing with what is external. They must succeed first in the laborious endeavour to ascribe all that they know best and most directly in themselves — as consciousness, feel- ing, and will — to all other existing things, and only then will the veil begin to lift itself which conceals the great secret. My task is here only to show the place occupied by Spinoza's doctiine in the course of the develop- ment of philosophical thought down to Kant's doc- trine of knowledge, and to indicate, as before, what new truths were contributed and what progress made by his help, as well as what was one-sided and incomplete. The gains were these : — 1. The establishing the idea of unity of substance, which put an end to the unnatural separation be- tween thought and extension. It was now possible to conceive every sensible process as at the same time a material modification of the organs of sense and as a variety or mode of consciousness. This salutary combination, arising out of the former no less salutary distinction or differentiation, lends clearly a double aspect to every question, i. e. quatenus res consideratur sub attribute extensionis, or sub attributo cogitationis. It is only a development of Spinoza's thought that leads Tyndall to give the characteristic title to his valuable work, ' Heat considered as a mode of motion^ i. e. according to Spinoza, is a modus extensionis. Everybody always knew that heat was also a modus cogitationis, i. e. a sensation. 2. Besides this, the notion of substance, as the last residuum of the old ontology, tended to evaporate SPINOZA. 199 into a single final unity, which strictly speaking amounted to nothing but piire, i. e. empty being, as to which men could know nothing whatever, except in so far as they themselves participate in that being. A complete change of front was thus effected. Hitherto the whole expenditure of strength had been directed to effecting conquests from the realm of one or other substance, but now it was both possible and necessary for the thoughtful intelligence to bring all its forces into the field against the idea of substance itself, and to show that this also was the creation of reason and must have its existence justified thereby. This, which was accomplished by Kant, is the turning- point in the history of philosophy: before him it was ontology, after him and through him it became dia- noiology, or a theory of knowledge. 3. It was one of Spinoza's merits to have intro- duced the conception of an absolute and perfect knowledge, such as the reason always aspires after, in contradistinction to that which is limited, sub- ject to the course of causation in space and time, and therefore conditioned by the boundaries of advancing knowledge. The only absolute knowledge is that which considers things in their eternal, infinite con- nection in God, i. e. sub specie ^ternitatis, and with- out the limitations of space and cause, and refers them al] to the true final ground of all things, the causa sui \ Here are the true principles of all being and all knowledge ; here the two flow into one. They are eternal truths, which not only explain and are > 'Intellectus res non tarn sub duratione, quam sub quadam specie eeternitatis percipit et numero infinito ; vel potius ad res peroipiendas nee ad numerum, neo ad durationem attendit ; cum autem res imaginatur eas sub certo numero, determinata duratione et quantitate percipit.' De Intellectus Emendatione, sub fin. 200 MODERN PHILOSOPHY. presupposed by appearances and modi, but also lead us to necessary existence and reveal to us its true essentia. This true, perfect knowledge is opposed to the Hmited, which only conceives things in their component parts, as under the limitations of time, and space, and number. The latter occupies itself only with the affectiones, the modi of substance, not with its true essentia''-. Spinoza overlooked at this jDoint that, according to his own definition, man himself was only an ephemeral modus of the infinite substance, and that it was as impossible for a transitory intellect, hemmed in on every side by limitations, to conceive infinite substance sub specie seternitatis, as it would be to thrust out from some rapidly moving body a lever that was to uproot the fixed world from its seat. Still this contrast between true, absolute, and uni- versal knowledge, and that which Avas limited by time, space, and causation, served to show the way to a clearer insight. It led to the salutary recognition of the limits of our reason, which forms the real task of metaphysics. Starting from this view, Kant was enabled to show that the first kind, absolute knowledge, is the unattainable ideal of human reason, which always strives after perfection ; while the latter ^ ' Seriem rerum singulavium mutabilium impossibile foret humanee imbecillitati assequi, cum propter earum omnem numerum superantem multitudinero, turn propter infinitas circumstantias in una et eadeni re, quarum unaquseque potest esse causa ut res existat aut non existat. Quandoquidem earum existentia nullam habet coiinexiouem cum earundem essentia sive (ut jam diximus) non est seterna Veritas Intima rerum essentia tantum est petenda a fixis atque Eeternis rebus et simul a legibus in iis rebus tanquam in suis veris codicibus inscriptis, secundum quas omnia singularia et fiunt et ordinantur ; imo hseo mutabilia singularia adeo intime et essentialiter (ut ita dicam) ab iis fixis pendent, ut sine iis nee esse nee concijii potsint.' De Tntellectus Emendat. SPINOZA. 20 I kind represents its necessary process, its one final possession, the forms into which it must translate the whole phenomenal world. 4. In many passages, and especially in his Trac- tatus cle InteUectus Emendatione, Spinoza displays a clear and penetrating insight into the true nature of knowledge and the path by which it must be reached, namely, a criticism of the intellectual faculties. He is clearly feeling for what Kant subsequently de- signated as the a ][)riori element in human know- ledge. ' In order to distinguish true and false ideas, we must,' he says, ' learn to understand the pecu- liarities of the intellect,' True thought is that which embraces objectively in itself the essence of a principle which needs no cause and can be known in and by itself The form of true thought must hence be sought in itself, not in its relation to other forms ; and it must not be derived from its own object, as if it were caused by that, but from the native force and nature of the intellect itself.' He gives as an instance an idea vera, the object of which depends upon our vis cogitandi and is not to be sought in rerum natura, and naturally selects a geometrical figure, the circle, for the purpose. He then adds : ' Unde sequitur simplices cogitationes non posse non veras esse, ut simplex semi-circuli, motus, quantitatis, etc., idea/ He speaks in the same way, at the beginning of the Tractatus, of the vis nativa, or native force of the intellect, which he explains as 'illud quod in nobis a causis externis non causatur ; ' and he characterises as an important task the attempt to enumerate all those ideas which are derived from the pure intellect and to separate them from the ideas of the imagination. Af the same time he warns the student against drawing any con- 202 MODERN PHILOSOPHY. elusions from abstractions when he is dealing with actual things, and not to confound what belongs to the nature of the intellect with the real facts about particular things i. Finally, he insists, as upon the foundation of all true knowledge, on the need to seek first the cognitio intellectus ej usque proprietatum et virium ; and at the same time he points out that in everything else truth is only reached by the help of correct definitions, tested and established by corre- sponding methods, while as to the intellect we are left without any further test or standard, so that the correct definition must be self-evident : ' quod vel definitio intellectus per se debet esse clara vel nihil intelligere possumus.' All these are so many finger-posts, point- ing and preparing the way to a future examination of the pure intellect, or pure reason, its vis nativa, 2)T0prietates, and the like. 5. Lastly, it should be noticed that Spinoza, like all considerable thinkers, was well aware of the source of error lying in words and the self-deception of the human mind, which, as soon as it meets with a word, forthwith imagines that some equivalent thing or reality must exist to correspond with it. ' For as much as words are part of imagination, that is, ^ In the Appendix to the Cartesii Principia Philos. more Geometrioo Demonstrata (1663) Spinoza insists, ahnost in the very words of Kant, upon the difi'erence between the entia rationis or viodi cogilandi and real things : ' Ex omnibus supra dictis inter ens reale et entis rationis ideata nullam dai'i convenientiam apparet. Unde etiam facile videre est, quam sedulo sit cavendum in investi- gatione rerum, ne entia realia cum entibus rationis confundamus. Aliud enim est inquirere in rerum naturam, aliud in modos quibus res a nobis percipiuntur. Haec vero si confundantur, neque modos percipiendi, neque naturam ipsani intelligere poterimus ; imo vero, quod maximum est, in causa erit, quod in magnos errores inci- demus, quod plerisque hucusque accidit.' SPINOZA. 203 since we form many conceits, according as words are framed in the memory, at random, by reason of some bodily state ; so it is not to be doubted that words like the imagination may be the cause of many errors unless we guard ourselves against them with much care. Add to this that they are constituted to suit the taste and capacity of the vulgar, so that they are only signs of things as they are in the imagination, not as they are in the intellect, which is evident from the fact that on all those things which exist only in the intellect and not in the imagination negative names, such as incorporeal, infinite, etc., are always imposed : and even many things which are truly affirmative men express negatively, such as un- created, independent, infinite, immortal, etc., because the contraries of these are much more easily imagined; therefore these occurred first to the first men and usurped the place of positive names. We affirm and deny many things because the nature of words, rather than that of the things, admits of the affirmation and denial, and in ignorance of this we might easily take something false for the truths' The principal defect of Spinoza's system lies naturally in his idea of substance and the way in which it is educed ; so that in the first preliminary conception existence is tacitly imputed to the subject, and then analytically deduced from it, like the con- juror's trick in which, to the astonishment of the pubhc, an article is discovered where the performer has secretly had it placed beforehand. This leap from the mere idea, or what is thought, into the actual world is the most violent and break-neck salto mortale to be met with in any system of philosophy. If Spinoza had remained faithful to his demand, ' De Intellectus Emendatione, xi. § 88. 204 MODERN PHILOSOPHY. conceived in the true Cartesian spirit, that enquiry should start with the nature and properties of the intellect, he could not have failed to discover, that just as time, space and number, by which all things are explained, are yet themselves only modi cogi- tandi ^ similarly the idea of cause or causality is an original, not to say the only original possession of our reason ; and must therefore be first investigated, in all its varieties, ramifications and functions, before any direct application may be made of it to the world, or the degree of its certainty or reality. He ought therefore, before inferring a first cause of aU beings, and thence deducing his ideas of substance or God, to have verified the idea of causation within the subject itself, and then only have proceeded to enquire whether and how far this idea justifies a transition to a world of thought and matter, mani- festing itself in time and space. But he failed to enter on this verification, and the omission proved fatal at once to the first foundations of his system, and (at least in part) to its further development. It has been noticed already how persistently Spinoza confounds and identifies cause with reason in the obvious intention of arguing from ideas to realities^- In this indeed he was only following in the wake of Descartes, with his ontological proof of the existence of God. But in Descartes there was still some approach to a rational sequence, and the idea of God appears as the reason of his existence. Sjiinoza, on the other hand, creates at once a cause, by describing God, or what comes to the same thing, substance, as causa sui, which is as great a con- 1 Cogitata Metaphys. cap. i. ^ Cf. Schopenhauer, Vierfache Wurzel des Satzes vom zureich- enden Grrunde, p. 1 3, and examples there collected. SPINOZA. 205 tradiction or non-sense, as if it were said that some- one was his own father. I have already pointed out how Spinoza was dazzled by the methods of mathematics, or geometry, in which objects and definitions have their rise together, so that he began to dream of applying the same method with equal results to philosophical ideas. Hence his frequent comparison : as it follows from the nature of the triangle that the sum of its angles equals two right angles^, so, with the same necessity, it follows from the idea of the deity both that it exists and that it contains and produces all things. This is clearly expressed in the Ethics (i. 16), 'Ex data cujuscunque rei definitione plures proprietates intellectus concludit, quae ex eadem necessario sequun- tur,' whereupon, ex necessitate divinse naturse, infinite attributes may be deduced. At the same time, the Deity is also the efficient cause of all things. That mathematical certainty is the norm of trvtth, that its decisions are eternal truths, equally valid in all times and places, that its laws supply the firmest founda- tion for all other knowledge, as in mathematics itself everything is deduced from a few postulates, axioms, and definitions, — all this contributed to make it Spinoza's ideal of true knowledge. Spinoza's relationship to Descartes may also be characterised in this way. The latter took refuge in the transcendental idea of the Deity, to whom all things are possible, in order to prove the reality of the material world and the equivalence of the two substances. Spinoza took this equivalence seriously, ' 'Cum attendimus ad naturam trianguli, invenimus ejus tres angulos esse sequales duobus reotis ; si talem liabemus cognitionem Dei qualem habemus trianguli, turn omnis dubitatio tollitur.' De Intellectus Emendatione. 2o6 MODEKN PHILOSOPHY. and wished to show how the possibility became actual. He realised the transcendental idea and made the Deity into an immanent cause, by identifying God and the world and combining extension and thought in the same substance. However much of truth there may have been in the fundamental thou.a-ht, its execution was laboured and confused; all the more so because Spinoza, while postulating the idea of causation, everywhere assumed the ex- istence of only one kind of causation, and en- deavoured in consequence to represent thought as subject to the same kind of strict causal sequence as material changes, both being independent in themselves, and yet held together in necessary re- lationship. A thought can only be limited by a thought, a body by a body; each thought must be deduced from another thought, and so on to infinity, while a body can only be determined to rest or motion by another body. Spinoza's attempt to make it clear to himself and others how these two attributes, extension and thought, in complete causal independence of each other, can yet be so joined together in the same being as to be regarded as qualities of it — this attempt must be held to have failed altogether ; and again for the same reason; namely because it did not start from a thorough and exhaustive theory of knowledge, but only aimed at translating everything into ' reality.' Attention should be paid more especially to the contradiction involved in assuming extension to be a quite sj^ecial quality, altogether independent from thought, when in fact we can never know anythmg about this extension except what is contained in our thought concernina; it, so that at last everv- thing must be referred to that one quality. Spinoza SPINOZA. 207 himself says\ ' Sic etiam modus extensionis et idea illius modi una eademque est res,' which, as Scho- penhauer well observes, can only mean that our idea of bodies and the bodies themselves are one and the same thing. And all the while no proof is given of the existence outside our thought of something real, answering to our idea, but distinct from it. 'We have thus,' Schopenhauer contiiuies^, ' a complete realism in Spinoza's doctrine, so far as. the existence of things corresponds to the idea of them in our minds, for the two are one ; and therefore we know things as they are in themselves. They are extended in themselves (extensa) just as they present themselves in our minds, when they become the objects of thought (co- gitata). . . . Spinoza draws the line altogether on the ideal side, and stops short at the world as pre- sented in thought ; the latter, as characterised by its form, extension, he holds to be the real, which exists moreover independently of its presentation in thought. He is thus certainly justified in saying that what is extended and what is thought of, i.e. our idea of bodies and the bodies themselves, are one and the same. For things are only extended as they are thought and only thought of as extended ; the world as idea and the world in space are iu:ia eademque res. We have no difiiculty in conceding this. If extension were a quality of things in themselves, then our perception of it would be a knowledge of things in themselves ; he assumes this, and herein consists his realism. But as he has not laid its foundations by showing how a world of space exists, corresponding to the independent world thought of as extended, the fundamental problem remains un- solved. . . . Spinoza's bias towards the ideal side ^ Ethics, ii. Prop. 7, Schol. '^ Parerga, i. pp. 10-13. 208 MODERN PHILOSOPHY. shows itself in his readiness to beheve that reah'ty was to be found in the extension pertaining thereto, and the consequent acceptance of the perceptible world as the only reality outside ourselves, and the knowing subject (cogitans), as the only reality within us. And in the same way, on the other hand, he reduces the only true reality, the will, into an ideal, by making it a mere modus cogitandi, and indeed iden- tifying it with the judgment. (Eth. ii. Prop. 48, 49, "per voluntatem intelligo affirmandi et negandi facultatem;" and again, " concipiamus singularem ali- quam volitionem, nempe modum cogitandi, quo mens aftirmat, tres angulos trianguli sequales esse duobus rectis;" which is followed by the corollary, "Voluntas et intellectus unum et idem sunt ").' This severe criticism, which is just enough, so far as it refers to the object of knowledge, must be qualified by the consideration that Spinoza was the first to venture upon treating things, which presented themselves to our faculties of perception as alto- gether heterogenous, as qualities of one and the same being ; and to say, this thinking subject is at the same time matter and mind, these two are therefore only properties, not independent things. All drawbacks notwithstanding, this was an important progress. Great confusion and obscurity has been caused by the adoption among the successors of Descartes of the use of the term cogiiatio, which, as has been shown, was used by himself to characterise all the modifications of consciousness, in the widest possible sense. The point becomes clearer exactly in pro- portion as we approach the question, What is thought, strictly speaking, and how is it distinguished from other forms of consciovisness ? a question first fully and lucidly dealt with by Locke. SPINOZA. 209 Spinoza indeed contrasts reason and imagination, and says that the interchange of words and images with rational ideas is the cause of most errors, and accounts for this in the following words ^ : ' Verborum namque et imaginum essentia a soils motibus cor- poreis constituitur qui cogitationis conceptum minime involvnnt :' but he makes no attempt to investigate the connection between the ideas of reason and the imagination and sensible perception, contenting him- self with the most superficial explanations. The nature of ideas at least should have been clearly set forth, but on this point too he remains thoroughly obscure. Sometimes, as in the passage quoted above (p. 201), these ideas are identified with the simplest and most general conceptions, such as time, space, motion, mathematical figures, &c. Sometimes he tells us 'ideam quatenus est idea affirmationem aut ne- gationem involvere^,' which puts the idea on the same level as judgment. Then again he speaks of an idea ' rei singularis actu existentis ^.' Sometimes mind is the 'idea corporis*;' sometimes 'mentis idea' and 'mens' are 'una eademque res^;' sometimes the 'idese affectionum corporis ' are what the mind perceives ", and sometimes, in his own words, ' idea mentis (hoc est idea ideas) nihil ahud est quam forma ide^ quate- nus h«c absque relatione ad objectum consideratur ; simulac quis aliquid scit eo ipse scit se scire et simvl scit se scire quod scit, et sic in infinitum.' In short the word is used with the most fatal want of pre- cision, and resembles anything rather than an idea clara et distincta. The reason of all this confusion is that the boundary ^ Eth. il. Prop. 49, Schol. " Loc. cit. ' lb. Prop. 9. * lb. Prop. 12, 13. ° lb. Prop. 21. ' lb. Prop. 22, 23. VOL. I. P 2IO MODERN PHILOSOPHY. line is not sharply drawn between tlie Ideal, as the intelligent principle in the subject, and the Eeal, as the objective world, or matter of thought. Do- minated by his leading idea, that the ^vorlds of extension and thought are parts of the same sub- stance, Spinoza insists upon this truth, repeating it sometimes of the thinking subject, sometimes of the matter of thought, i. e. the material world. The only result of which is increasing confusion as to the notion idea, which sometimes denotes, as in the Platonic theory, the intellectual plan in accordance with which the material form of things is realised, sometimes the representation which the intelligent subject has of this plan, and, finally, sometimes the inner spiritual side of the subject, i. e. consciousness and thought. If the mind is the idea of the human body, it makes a considerable difference whether I understand by this mind, the living active principle which finds its adequate expression in the body, or the thinking being itself, or, lastly, the conscious- ness that this mind has of itself and of the affections of the body. This continuous interchanging of ob- jective and subjective constrained Spinoza to have recourse always to his God, as the sole possessor of adequate ideas of all things, whose ideas are com- pletely realised in the material world, so that it is plainly in this connection that the proposition is laid down (Eth. 3. 7), ' Oido et connexio idearura idem est ac ordo et connexio rerum.' Geometrical figures, i. e. those objects which come into existence by being thought, supply the illustrations here also. A really existing circle and the idea of this circle, which is in God, are one and the same. The circle, in so far as it is an extended thing, must be explained solely from the divine attribute of extension; the SPINOZA. 2 1 1 idea of the circle, on the other hand, must be derived from the next idea, and this again from another idea, and so ad infinitum, but always from something con- tained within the intellectual nature of the Deity. Here we should be justified in asking Spinoza to ex- plain how it comes to pass that two quite different causal series, the ordo et connexio idearum and the ordo totius naturae per extensionis attributum, con- tinue to subsist in complete parallelism, and why they can only be attributes of the same being. But we are told only, 'nee in preesentiarum haec clarius possum explicare.' (Eth. ii. 7, Schol.) This fundamental obscurity necessarily becomes increasingly obvious when human thought has to be explained. The true principle indeed is laid down (Eth. ii. 19) that the human mind is not conscious of its own body, and only knows it in so far as it is affected by other bodies. But instead of deducing thence the difference between thought or objective knowledge and mere dim consciousness or impulse, we are simply referred again to the Deity in whom, as an intellectual being, the true idea of our body and its modifications is to be found. In general, notwithstanding Spinoza's zeal against the application of human ideas to the universe, notwithstanding his protestations that good and bad, perfect and imperfect, ideas of design and such like, are absolutely inapplicable to the world as such, notwithstanding his care to eliminate altogether the idea of personality from his God, there is still an undeniable touch of anthropomorphism in his re- presentation of God as a tMnldng being, and the whole percej)tible world as a manifestation of his nature or a realisation of his ideas. He has quite omitted to observe that human thought — the only p 2 :2I2 MODERN PHILOSOPHY. kind from whicli we can draw any inferences as to the nature of other thought — necessarily presupposes an individual being, and a,n external world contrasted therewith, by which it is affected and supplied with the material for its thought. In the One, which is at the same time the All, difference and consequently consciousness and thought necessarily disappear. Thought is not a fundamental property of the world ; human thought and human reason have been pro- duced as an accident of this world ; our reason itself is finite, its duration exists in time, it had a beginning, and will not endure for ever ; it would be pre- sumptuous to ask what may come after it. But Spinoza attributes infinite thought to his God- World ; his God is like an architect, whose living stones are individual beings, men included ; each single being cor- responds accordingly to an idea of the Deity, though but imperfectly informed itself as to its nearest re- lations, and only able to attain adequate ideas of things by thinking them in their relation to God. Confused and imperfect ideas only arise from our having a partial consciousness of consequences apart from their premisses ^ Before closing this section it will be well to enumerate once more the points of most value to later generations of thinkers, which have been be- queathed to us by this seemingly obscure and per- plexing doctrine. And of these, first, the conception of nature as something living. There is nowhere ' Eth. ii. 28, 29. Cf. De Intellectus Emendatione : 'Quod si de natura entis cogitantis sit, uti prima froiite videtur, cogitationes veras sive adsequatas formare, certum est, ideas inadeequatas eo tantum in nobis oriri, quod 2>ars suiims alicvjus entis cogitantis, cujus quEedam cogitationes ex toto, qufedani ex parte tantum nostram mentem constituunt.' SPINOZA. 2 1 3 bare matter or passive machinery. All things, in- cluding apparently inanimate matter, have some inner quality. The degrees of consciousness may be thought of as infinitely various ; there is no consciousness so faint but what it might become still fainter, no clear reflectiveness but what may aspire after still higher clearness. It is true Sj)inoza should have placed this doctrine, which seems so incompatible with our re- ceived notions, in the foreground, instead of only re- ferring to it occasionally and as it were by the way: ' omnia, quamvis diversis gradibus animata,' &c. (Eth. ii. 13.) The fundamental principle of Monism should be, the more exclusion or isolation, the less conscious- ness. This idea was indeed first made possible by Leibniz, who made due allowance for what is in- dividual, and made that his starting-point, while Spinoza's ' thinking substance,' in spite of his efibrts to the contrary, by its assimilation to the thinking- man, necessarily tended to personify and individualise the All. 2. The Monistic idea casts an especially clear ray of light upon the great mystery of human thought. While antiquity failed to recognise any distinction between words and ideas or thought and speech, the epoch-making generalisation of Descartes has enabled us to distinguish between a word, the utterance ot which is only a bodily change or motion, and its spiritual content, the idea. Both Descartes and Spinoza showed the general and not yet extinct behef that thought is antecedent to speech, and that the soul is thus first in possession of ideas which it subsequently denotes or expresses in words. Down to the second half of the present century we meet with no trace of a perception of the dependence of thought on language, which must be called not only 214 MODERN PHILOSOPHY. the fulcrum and adminiculum, but the very lody of thought. And yet it is a thought quite in harmony with the spirit of Spinozism, that language and thought are one and the same thing, only viewed from different sides, i. e. once quatenus res est ex- tensa, and once quatenus res est cogitans, or as ex- ternal and internal ; that the two are distinguishable, but not separable; that it is just as impossible to have thought without language, as language without thought. Not less certain is it that the ohject of speech and thought, i. e. that which we are in the habit of characterising as the matter, or content of thought, could have no existence without this two-sidedness of the material and the mental elements. For there is no external w^orld capable of being grasped at once by our thought, without a preliminary idealising transformation, so that all external existence must undei'go a kind of traussubstantiation ; just as every- thing internal or spiritual, before it can be spoken or thought, must be converted into sometliing material or sensibly perceptible. This proceeding of language, which is known as the metaphorical or tropical, used to be generally regarded as a mere rhetorical ornament, although a glance at any dictionary would have sufficed to prove that it constitutes the real essence of language. The idea of matter has as much of an ideal character as the idea of spirit has of a material and sensible origin (spiritus, anima, ruach). Neither are things in themselves, but both objects of thought ; and in this the philosophy of language agrees entirely with the Transcendental philosophy. 3. Objects, says Spinoza (Eth. ii. 5), are not the cause of ideas ; the enchainment of ideas depends wholly and solely upon the intellectual nature of the SPINOZA. 2 I 5 Deity, so that one idea follows and springs from a preceding idea, and so on in infinite succession. An element of profound truth must be recognised here, however strange and repugnant it may seem to us to assume strict causation betw^een ideas, without any reference to their objects. I will not insist here upon its transcendental result, that thought must necessarily contain within itself the principles of truth, since it cannot possibly receive them from external objects, which virtually establishes the independeace of the intellectual principle from the external material world. Neither will I point out here that the whole development of the universe, in which one form always proceeds from a kindred form, can never be made intelligible by means of mechanical causes pertaining to the world of extension ; but must be regulated by the intelligent principle, though indeed neither the Platonic, nor the immanent ideas of Spinoza adequately elucidate the problem. It will be enough to show the validity of this proposition of Spinoza's in regard to the creative energy of the human mind, and especially the development of lan- guage and concepts. For the activity of mankind, the revolutions effected by men on the world's surface, are not caused by external objects, but wholly and solely by the inner, active intellectual nature of mankind ; their origin is traceable through an immeasurable chain of past races, during whose transitory existence in like manner thought has proceeded from thought and creation from creation in a spiritual sequence of the same continuous causal character as the illimitable generations of animal species. It is also one of the most certain discoveries of the science of language that never, in the whole course of linguistic develop- ment, has a word or notion been educed from an 2l6 MODERN PHILOSOPHY. external object, but always uninterruptedly an idea from an idea, as in the outward activity of men creation follows creation, — a literal confirmation of Spinoza's proposition, 'Kerum singularium idea; nou ipsa ideata, sive res perceptas pro causa efiiciente agnoscunt, sed ipsumDeum, qiiatenus est res cogitans,' in which we have only to read the intellectual j)rin- ciple, or human reason, instead of Deus. Geiger ob- serves, in agreement with Spinoza, 'Language and thought are only made intelligible to us when we discern that our will is not a contemporary offspring of a given stimulus, nor our belief of an intuition, our conception of a phenomenon, or our thought of an object ; but that it is the past, — from the beginning when the All emerged from primasval nothingness, down to the present moment, when an atom of the eternal world-force has constituted this ego of ours, — which lives, believes, thinks and feels in us; and that therefore it is behind, not around u.s, that we must look for the key to the riddle within and with- out and the source and origin of all true being The forms of thought do not proceed either from us or from things — from field and wood, as the poet has it ; but each one of them had its rise and origin from a preceding form, as one animal generation gives birth to another \' Thus the nature of thought consists not in perceptions of objects, but in conceptions, re- ceding in unbroken filiation through an immeasurable past, in an order which science must trace back to the hoar anticpiity in which thought and language had their beginning. This holds good not only of all thought, but of the perceptive faculties as well, which have become so highly developed in mankind ' L. Geiger, Ursprung und Entwickelung der mensohliclien Sprache und Vernuuft, i. p. io8. SPINOZA. 217 as a consequence of this mental activity. The same truth must even be applied to the sensible perceptions of the lower animals, which are also impossible with- out some germs of thought. We and they perceive things as we do, because of the immeasurable suc- cession of intuitions and perceptions which has gone before us in the past, and which is being continued, through the present generation to future ages and races. Mind begets mind, consciousness consciousness, perceptio ex perceptione, conceptus ex conceptu, idea ex idea. Isolated mechanical existences afford us no explanation ; we can only admit that such and such mental phenomena would be impossible without such and such material ones. And it is easy to see what tragical results must follow, from the confusion and interchange of the two elements, if we glance at the numerous and ill-fated theories of the origin of language, which have attempted to estabhsh a causal connection between the mental content of ideas and the audible sounds of words. 4. It appears from many passages, both in the Ethics and in his letters, that Spinoza was fairly on the way towards Transcendental Idealism, and therefore to the Kantian doctrine, according to which phenomena must be distinguished from things in themselves. In the interests of clearness he should at this point have freed himself from the Cartesian ideas of substance, cause, &c., or rather have subjected them to careful investigation. He says (Eth. ii. 16) that the way in which we are affected by external things depends much more upon the constitution of our body than on the nature of the external things. In the Scholium to the seventeenth Proposition he adds : ' Corporis humani affectiones quarum idese corpora externa velut nobis preesentia reprEesentant, rerum imagines 2l8 MODERN PHILOSOPHY. vocabimus, tametsi rerum figuras non referunt ; ' and continues that the mind does not err so loDg as it stops short at imagination ; error only begins when these things are assumed to exist objectively. He even admits that the self-knowledge of the miud can- not proceed further than a conception of the affections of the body (prop. 23). Similarly he observes (prop. 25) that an adequate knowledge of the foreign bodies acting on our own cannot be derived from the affec- tions of the latter, which is an admission that a true knowledge of things in themselves is impossible, for (prop. 26) ' mens humana nullum corpus externum, ut actu existens percipit, nisi per ideas affectionum sui corporis.' And in the corollary to prop. 29, the con- clusion of the whole matter is summed up, that the human soul, in so far as it contemplates things accord- ing to the common order of nature, cannot attain to adequate but only to confused and partial knowledge either of itself, its own body, or external things. In reference to Space and Time, Spinoza also gives expression to views which seem like a faint fore- shadowing of the Kantian doctrine. Even in the Cogitata Metaphysica he says (cap. 4) that the duration of a thing is non nisi ratione distinguishable from its existence, and that this accordingly is a token of its existence, but by no means of its essence. In like manner he observes in the passage above quoted (p. 202, note) that there can be no real agreement between actual things and the modi imaginandi; and he includes among these entia rationis, ' tempus, numerus, mensura et si quas alia sunt.' He expresses himself most clearly in the 29th Letter ^, where he distinguishes the knowledge which is limited by space and time from the true knowledge ' Opera, ed. prino. p. 467. SPINOZA. 219 which deals with the eterua], infinite, and indivisible substance ^ : ' Moreover since we can determine du- ration and quantity at will, conceiving the latter apart from substance, and the former apart from its relation to things eternal, time and measure (space) come into being ; time to determine duration, and measure to determine quantity, in order that we may imagine them as easily as possible. Then because we separate the affections of substance from the substance itself, and classify them, in order that we may imagine them the moie easily, numler originates, whereby we determine the same. From which is clearly to be seen that measure, time, and number are nothing but modes of thought, or rather of imagination (i. e. according to Kant, forms of sensibility). Where- fore it is not strange that all who, by the help of similar notions, and these moreover badly under- stood, have attempted to interpret the course of nature, entangled themselves marvellously in such wise as to be unable to extricate themselves without violence and the admission of absurdities, yea of the very utmost absurdity. For there are many things which are not accessible to the imagination, but to the intellect alone, svich as substance, eternity, and others. And if any one endeavours to explain such things by means of notions which are only auxiliaries of the imagination, he is only as it were labouring to make his imagination run mad. For even these ^ ' Quantitas duobus modis a nobis concipitur : abstracte scilicet, sive superficialiter, prout ope sensuum earn in imaginatione babe- mus, vel ut substantia, quod non nisi a solo intellectu fit. Itaque si ad quantitatem prout est in imaginatione attendimus, quod sasjDis- sime et facilius fit, ea divisibilis, finita, ex partibus composita et multiplex reperitur. Sin ad eandem, prout est in intellectu, at- tendamus, et res ut in se est, percipiatur, quod difficillirtw fit, turn ut satis demonstravi, infinita, indivisibilis et unica reperietur.' 2 20 MODERN PHILOSOPHY. modes of substance can never be rightly understood, if they are confounded Avith these entia rationis or auxiUaries of the imagination. For when we do this we separate them from substance and the mode in which they have proceeded from eternity, without which they cannot be rightly understood. ' For the clearer apprehension of which, take this example : — If any one were conceiving duration in the abstract ^, and then, confounchng it with time, proceeded to divide it into parts, he would never understand how e. g. an hour could pass away. For in order that an hour should pass away, first the half must pass and then the half of the remainder, and then the half of that remainder, and if one continues thus dividing to infinity one will never come to the end of the hour. Therefore many who are not accustomed to distinguish the things of the mind from realities maintain duration to be composed of moments, and so fall into Scylla in their desire of avoiding Charybdis. For to make dviration consist of moments is the same as to make number consist of the addition of noughts. ' But from what has been said it appears sufficiently that neither number, nor measure, nor time, since they are but aids to the imagination, can be infinite (for otherwise number woidd not be nimiber, nor measure measure, nor time time) ; hence too is clearly to be seen why many who confound these three with actual things, because they are ignorant of the true nature of things, actually deny the existence of the Infinite.' It only remains now to indicate summarily the great stride in the progress of philosophical thought marked by Spinoza's doctrine. It is true that his ^ i. e. in itself, apart from its relation to eternity. SPINOZA. 221 conception of substance seems on the one hand to make all knowledge impossible, and on the other to make all experience superfluous ; for if our appre- hension of things in time and space is only an illusion of the senses, if all determination is negation, by what ladder can the human mind, which has no resource but in these forms, scale the height from which it is to view the universe sub specie seternitatis ? But all this notwithstanding, it should be remembered that Spinoza was the first to realise that ideal of Reason towards the unity and completeness of which others had aspired in vain, and that thus through him scientific Tcnoivledge, in the special sense of the word, first became possible. It is certain that all pluralism is a shock to reason, and that a multiplicity of fundamental principles represents only so many unsolved and incomprehen- sible riddles. As in religion primitive polytheism naturally passes into monotheism, so philosophical speculation, after having tentatively brought toge- ther the most various principles as constituting the nature of things, must end by attaining to a unity in which all these principles meet and harmonise. This is the way in whicb human reason is compelled by its nature to proceed. Its endeavours can only be arrested if it pauses on its course to consider and ex- amine its own nature, and so makes the discovery that this unity really lies only in itself \ and that the ^ ' The order and regularity in phenomena, which we call nature, is supplied by ourselves, and we should not find them there unless we had first imported them. . . . Extravagant and absurd as it may seem to say that the understanding is the source of the laws of nature, and therewith of the foi'mal unity of nature, such an as- sertion is as correct as it is conformable to its object, namely ex- perience.' Kant, Critik der reinen Vernunft, pp. 112, 114. 222 MODERN PHILOSOPHY. world can never offer it what it seeks ; in other words, if it discovers that the work of philosophy consists in tracing out the limits of human knowledge and in teaching ' Quid valeant humeri, quid ferre recusent.' Spinoza represents the culminating point in this endeavour to find unity in the world of reality. It is undeniable that ancient philosophy ended in plural- ism. The Platonic ideas stand in no such relation to each other as that one generates or conditions another in any way that would enable them to be combined in a regular system, explanatory of the actual order of the world. In like manner the Aristotelian Forms, or Entelechies, have an unavowed multiplicity, which cannot receive the slightest elucidation from the con- ception of matter, from which they were all formed. These ideas onlv cease to be unintellia:ible, as the human mind comes to be recognised as the native soil whence they naturally originate, growing up in constant causal coherence. The memorable turning- point after which this knowledge became possible was reached on the day when Descartes consigned to philo- sophy, as a secure and inalienable possession, the one word Cogito. I say it became possible, for everything else had still to be accomplished by the philosophy of the future. The other principle introduced by Descartes is far more perfect, indeed almost entirely complete — the one namely by which he swept away the Aristotelian formse substantiales, the occult qualities, quintessences, &c., and established once for all a solid base for science — the principle of mechani- cal causality. Something however of the unsatisfactory incom- pleteness belonging to pluralism still adhered to the surviving unqualified dualism. The labours of the SPINOZA. 223 mind were lessened, but not wholly relieved. The mathematical nnethod had introduced the strict rule of law in the external world, but where were the laws of the immaterial substance to be found ? The mind was supposed to be in possession of certain eternal truths, and it was maintained that whatever was dare et distinde discerned by the mind had a claim to certainty; but where was the criterion of certainty, where the system which is to deduce every- thing here from the uniform nature of thought and consciousness, as elsewhere from the single principle of extension and motion ? It cannot be denied that the Eetemse veritates, the universal s, were an unfounded a priori, i.e. a concealed pluralism. Geulinx alone, by attending to the form of judgments, endeavoured for the first time to trace the operations of the mind, i.e. the nature of thought, and, as we have seen, disclosed the real lurking-place of the notion of substance. Another weakness on the same side of the Cartesian dualism must also be noted. The only thing which is really ^ls, which is in our own power, is our thought, by which Descartes understands all forms of con- sciousness, knowledge, will, imagination, sensible per- ception, &c. This is, from one point of view, the great truth of idealism, that the source of all direct know- ledge is to be found in consciousness ; but from another — latet anguis in herba. Are our thoughts really so much in our own power ? Or are we not rather, in re- lation to them, conditioned and overruled by countless influences which have their source in the thought of our contemporaries and, still more, in that of an- tiquity 1. And even if thought were really thus inde- pendent, if furthermore the will were subject to its dominion, what does that prove concerning this 2 24 MODERN PHILOSOPHY. spiritual substance? Does it not tend to become a mythological entity, whieb so far from being and working in subjection to universal laws, would just think and act because it chooses 1 In other words, in spite of the apparent simplicity of the two prin- cijjles, is not the purely individual element introduced here, on one side, which is quite as incapable of becoming the object of knowledge as isolated sense- impressions 1 Thus the Cartesian dualism is not only divided against itself ; even on the one — the intellectual — side there are numerous gaps and inconsistencies. This is especially obvious in the traces of its effects upon contemporary thought. The two substances, which have nothing in common with each other and there- fore cannot act on each other, are mutually indif- ferent and may subsist tranquilly side by side, so long as neither takes any notice of the other. But as this is not easily carried out, each time that they approach, great confusion and excitement is produced. The born man of science, a mathematician and me- chanician, is. distracted when reminded that there is such a thing as immaterial causation, and cries out, ' Noli turbare circidos meos ! Tbere is but one causal chain- — the mechanical. There is no excep- tion to the law of the conservation of force.' The genuine philosopher, on the other hand, to whose share the higher problems of the mind have fallen (not an apprentice escaped from the surgery or the chemist's laboratory), vexes his soul continuously over this stupid, lumjjish matter, which notwith- standing its phantasmal nothingness persists in thrusting itself staggeringly upon him at every turn. Spinoza delivered the human mind once and for ever from these perplexing torments, and any mortal, SPINOZA. 225 who suffers from them still, may turn confidently to his writings as a healing fontaine de jouvence. The universe has no outlaws ; strict causality rules every- where ; as miich in the world of mind and thought and conscience as in the material world where its presence is already generally assumed. Why should this seem an unwelcome infringement of the freedom of the will 1 Does not all rational and moral con- duct obey an internal compulsion ex necessitate naturae suaj, while fools and wild beasts own no such law and therefore seem in one sense more free '{ Science only becomes possible by this means, since the succession of things and events can only be explained if they are referred to the causal bond. Only between thought or consciousness and the attribute of extension in the material world no causal connection is conceivable ; they are two quite different properties, and there is no reducing them to an equa- tion, so as to allow of reciprocal causation. All serious thinkers, such as Descartes, Geulinx, Malebranche, and soon afterwards Leibniz, saw this plainly, and •sought for a third and higher cause which might be the common condition of the unquestionable parallel- ism between the two worlds. They all agreed in having recourse to the Deity as this third cause, while they overlooked or disregarded the simplest solution of the problem, namely, that the differing elements were one and the same. Why should they Bot be so "? Are not we ourselves walking instances of a similar possibility % Have we not all an inward and an outward property — the former will and con- sciousness, the latter motion ? Daylight dawns upon the widening prospect ; the sunrise crimsons the far horizon ; the old error has been explained away, and the forms of thought VOL. I. Q 2 26 MODERN PHILOSOPHY. suggested by false views of causal connection^ are dis- carded. How can an idea be the cause of a material creation % Because the Being that thinks is also at the same time an extended or material one, able to act upon the outer world in accordance with me- chanical laws. How can the mind be reflected in strange material elements % Because the sensitive being is at the same time provided with bodily organs, which are moved by strange bodies, and by their own sensitiveness act as intermediaries of per- ception. Thus there are creative ideas answering to natura naturans, and ideas which reproduce and reflect creation, natura naturata. There is no strange ghostly gviest lodging in the world ; every- thing partakes rather of its own nature, is flesh of its flesh and soul of its soul. Hence sensible per- ceptions have their place in the material world, and motion its significance for the world of spirits. The points where Spinoza's doctrine needed to be contiDued, developed, and corrected by his im- mediate successors may be enumerated as fol- lows : — I. In the first place, Spinoza's substance, or God- world, had swallowed up all difFerence and multi- plicity in its own unity ; it was therefore necessary to re-extract the really existing manifoldness and allot its proper place in the general order to each separate and special existence. This is done by the ^ E.g. I move my arm because I will. Because we tliiiik, we speak — clothe oin- thoughts in words. We first perceive an object and then project it externally. The mind is the cause of the development of the world, the world is the cause of the develop- ment of the mind, and so on. In all these examples, the applica- tion of the causal idea is erroneous, for in each case there is not causation but identity. SPINOZA. 227 recognition of Individualism, which constitutes the true essence of all separate existence. The propo- sition that all determination is negation is thus only partially true. (Leibniz.) 2. Spinoza's uniform application of the notion of cause to the world of thought and matter alike ■without distinction, must be set aside ; object and subject melt into one with him, and hence arises the frequent interchange of causa and ratio, the material cause and the mental reason. This essential distinction must be restored and clearly defined. (Leibniz.) 3. The beginning made by Spinoza, in recognising the causal dependence of spiritual phenomena, cleared the way for an attempt to examine more closely into the nature of human knowledge and its connection with sensible perception, an attempt which will throw light upon the importance and necessity of Empiricism. (Locke.) 4. Upon this the necessary distinction between subject and object becomes self-evident, and a criti- cism of sensible perceptions becomes possible in its turn, as we ask, what, in the last resort, is purely subjective, and what qualities belong to the object as such. The distinction between qualltates primariee and secundariee is contributed by Locke. 5. The superiority of human knowledge is due to its possession of a special class of objects which we call ideas or conceptions. By and with their help all human thought is accomplished. In order there- fore to decide upon their substance and reliability, the origin of ideas must necessarily be investigated, since they have neither existed from eternity nor been implanted by a miracle in man. (Locke.) 6. Spinoza's idea that the existence of individuals Q 2 2 28 MODERN PHILOSOPHY. was but partial and apparent needs to be further carried out. His recognition of the greater and less degree of reality possessed by these beings must be joined on to the perception, in all things, of gradual development and transition, by which the infinite variety and lavishness of natural forms is to be accou.nted for and explained. This principle of the continuity of forms must be applied also to the causal sequence and will serve to verify its pre- tensions. In this way the origiji of man, his higher liberty and intellectual superiority, becomes for the first time the object of investigation and a not in- soluble problem. (Leibniz.) 7. The definition of material substance, as laid down by Descartes, suffers from one grave imper- fection. According to Spinoza the universe is life and activity; jj)lus agere, minus ixdi is his measure of perfection, and thus he nowhei'e gives us anything really passive ; the true essence of things consists rather in their effective activity. Hence the mere empty idea of extension is insuificient — some other must be put in its place ; and for material sub- stances the only other possible is the idea of Force. (Leibniz.) THE EMPIRICAL TENDENCY. LOCKE (1632—1704). ' The proper study of mankind is man.' We have seen that Geulinx was the first to for- mulate the demand which it is the great merit of the Kantian Criticism to have satisfied ; and this demand, that philosophy should ascertain and trace the limits of human knowledge and understanding, was now clearly and expressly repeated by Locke. He says in the Introduction to his Essay concern- ing human understanding : ' I thought the first step towards satisfying several enquiries, the mind of man was very apt to run into, was to take a survey of -our own understandings, examine our own powers, and see to what things they were adapted. Till that was done, I suspected we began at the wrong end, and in vain sought for satisfaction. . . . Thus men, ex- tending their enquiries beyond their capacities, and letting their thoughts wander into those depths where they can find no sure footing ; 'tis no wonder that they raise questions and multiply disputes, which never coming to any clear resolution are proper only to continue and increase their doubts, and to confirm them at last in perfect scepticism. Whereas, ivere the capacities of our understandings well considered, the extent of our knowledge once discovered, and the horizon found, which set the bounds between the 230 MODERN PHILOSOPHY. enlightened and dark parts of things, hehveen what is and vAat is not comiwehensihle hy lis ; men would perhaps with less scruple acquiesce in the avowed ignorance of the one, and employ their thoughts and discourse with more advantage and satisfaction in the other.' Although it was plain that the Cartesian starting- point, the Cogito, must lead ultimately to this view, we must grant to Locke the same kind of praise as that accorded by Aristotle to Anaxagoras for having first recognised intelligence {yov^) in the world, since he first distinguished reason, as a special faculty in the mind, and thought proper, from the other so- called modi cogitandi, will, feeling, imagination, etc. He saw plainly that the essence of human superiority lay in this point, and that on it must rest the lever by which all the rest was to be upheaved. ' Since it is the understanding that sets man above the rest of sensible beings, and gives him all the advantage and dominion which he has over them, it is certainly a subject, even for its nobleness, worth our labour to enquire into.' A certain degree of mysticism or illuminism always lurked among the opinions of Descartes and his suc- cessors, since the seternaB veritates, and the 'clear and distinct' understanding, which are assumed with- out foundation, can only be finally explained by a participation in the divine reason. Reason as a natural gift, operating by natural means, and explicable by natural processes — this conception constitutes an undying title of honour for Locke, even when due weight is given to his obh- gations to Descartes, whose conception of the unity of all consciousness under the general idea ' Cogito ' had paved the way for a juxtaposition of sense and LOCKE. 231 reason, in whicli the latter could appear as lineally descended from the former. Now at last Empiricism had found the true course. The material world is no longer the only object of observation and intelligent examination : the con- nection between it and immaterial nature, the in- creasing volume of the latter as it is fed by all the streams of sensibility, in a word the growth and development of the mind itself, has become an open secret, of which any who will may henceforward master the key. Descartes had chased the meagre ghosts of scho- lasticism out of the field, and had rebuked the pre- sumptuous claims of the reason to contain within itself a treasure of facts and conclusions fit to solve all problems presented from without. Locke rendered the same service to the inner world. ' No Innate Ideas ' was the device under which he fought, repelling numerous and vigorous assaults. As, before Descartes, all matter was occupied by spirits, qualitates • occultge and formse substantiales, scaring from their entrenchments all reasonable ex- planations, so,' before Locke, innate ideas held un- disputed sway over the minds of men. The attack had to be directed against these, and only a life and death struggle could decide whether rational ex- planation or mysticism was to have the right of explaining the nature of reason itself Compromise was impossible, and, as we know, Locke emerged victorious from the affray. If ideas are innate they are a raysterj^, not to be investigated or explained. Throughout the con- troversy Locke follows the same ro,ute as nature, and begins by appealing to what is known of children. God, Liberty, Immortality — are these ideas innate. 232 MODERN PHILOSOPHY. already existing in the infant that can do nothing but scream when it is uncomfortable ? If however it is said that these ideas and truths are outlined already in the soul and pass into consciousness as the reason ripens, this is virtually saying that reason makes men know what they knew already. And then, where is the limit to be drawn 1 If mathematical truths are innate, all relations of space and number must be so equally; if aU self-evident propositions are innate, such truths as that sweet is not bitter, black is not white, &c., must be innate also. It did not occur to Locke to deny that much in the child was really innate, but everything upon which past philosophy had laid most stress, ideas, eternal truths of the understanding, as well as reli- gion and morality, in a word, rational thought and the highest peculiar faculties of humanity, are not innate, but, on the contrary, the product of develop- ment and individual acquisition, subject of course to the influence of education, without which indeed man can scarcely grow up human. If however the human child does not come into the world with an inborn treasure of certainties, truths, and conceptions, where then is the true origin, the sole prime source of all our ideas and knowledge, to be sought 1 In experience alone, which we receive by the gates of the senses : ' nihil est in intellectu quod non prius fuerit in sensu.' The soul is originally a tabula rasa, a blank sheet upon which experience and sensation write at will. On account of this empirical bent, Locke has been treated as a mere disciple of Bacon, while the views of the Fiench materialistic school, and more par- ticularly of Condillac, have been represented as the LOCKE. 233 logical outcome of his doctrine. In both these cases injustice is done to the philosopher. The external connection indeed cannot be denied, but by the philo- sophical s\ibstance of his doctrine, Locke belongs to the group of leading thinkers who approached seriously the greatest problems of nature and mind. The method of observation and experiment advocated by Bacon dealt only with nature, Locke's doctrine endeavours by the same method to solve the mystery of the Cogito. He is thus a worthy successor of Descartes, from whom he had learnt much. As to the French materialists, our estimate of their in- significance is shown sufficiently by the fact that it seems unnecessary to give them any place at all in this historical sketch, since their work consisted simply of wire-drawn reproductions of a few scraps and fragments of Lockian doctrine. Condillac's ex- planation of thought as une sensation transformee and the ingenious allegory of the animated statue have no claim to originality. French materialism was simj^ly a logical development of one side of Cartesian thought, combined with Epicurean sensual- ism and Lockian empiricism. All hinges on the two ideas of I'homme machine and joenser c'est sentir ^ Cabanis (1757-1808), Destutt de Tracy (i 754-1 836), and Maine de Biran (i 766-1824) were the first of the ' Diderot and Voltaire are exceptions ; the first too profound, the latter too clear-headed to rest satisfied with the empty hollow- ness of materialism. The former was by conviction a monist, the latter incHned to the same view, although it was not his nature to lose himself in philosophical depths. ' Je suis corps et je 2)ense : voiU tout ce que je sais,' Voltaire writes in his Letters from Eng- land, and he expressly declares that 'any one who maintains mere material movements to be sufficient to produce feeling and thinking beings, must have lost all traces of sound human under- standing.' Rousseau stands apart in his century. 2 34 MODERN PHILOSOPHY. French scliool whose efforts call for recognition. As a whole the school remained unfruitful, stopping short of the all-important truth, the connection between thought and language. The greatness of Locke is shown by his recognising this truth so much in advance of his age, even though the true source of the dependence, the identity of thought and speech, had not yet dawned on him. But his eagerness to probe the nature of human reason to the bottom, and the analytical skill n«eded to found this chief human gift upon a scientific basis, led him naturally into investigations of the nature of language, and these sections of his famous work are full of new and luminous points of view which contain some truth already, and the promife of more. Locke states it as his purpose 'to enqtiire into the original certainty and extent of human knowledge, together with the grounds and degrees of belief, opinion and assent, . . . and to consider the discerning faculties of a man, as they are employed about the objects (i. e. ideas) which they have to do with. . . . And 1 shall imagine, I have not wholly misemployed myself in the thoughts I shall have on this occasion, if in this historical, plain method, I can give any account of the ways, whereby our understandings come to attain those notions of things we have, and can set down any measures of the certainty of our knowledge on the grounds of those persuasions which are to be found amongst men, so various, different a,nd wholly contradictory.' Locke reckons sensible perceptions among simple ideas. The organs are the channels leading them to the mind. The soul is as little able to create ideas out of nothing or to destroy those which have been framed as a man is to create or to destroy the LOCKE. 235 smallest mote in tlie sunbeam. No idea of colour can be given to the blind, nor of sound to the deaf. Reflection is opposed to sensation. The latter is experience of the external world, the former of the inner one, i. e. the states of the souL The mind in this is sometimes active, sometimes passive. Per- ception is the representation of things external given by sensible impressions. The mind in this is purely passive, it is as powerless to escape or alter these im- pressions as a mirror to change the objects reflected in it. Retention is the revival of former representations, the important power of memory and recollection, and the mind in this is not wholly passive. There is a natural defect of the human mind, associated with the faculty of recollection, namely, that the latter only recalls its objects in succession : ' Whereas we can conceive some superior, created, intellectual beings which in this faculty may so far excel man that they may have constantly in view the whole scene of all their former actions, wherein no one of the thoughts they have ever had may slip out of their sight.' All these functions belong also to the lower animals. The highest property of the reason is the power to compare, distinguish, unite, and separate ; and in this the human mind far surpasses that of brutes, in virtue of the gift of abstraction, or universal notions, which he alone possesses, and of which anon. In all this we see a general outline of the analysis of mental operations, and their dependence on the world of sense, subsequently carried out with so much clearness and precision by Kant. Kant will modify and correct ; he will show that even in mere percep- tion or representation some active co-operation of the mind is necessary, such as is still more apparent in reproduction or recollection ; but the main outline was 236 MODERN PHILOSOPHY. drawn by Locke. The opposition insisted on by Kant between mere receptivity, or passivity of sensibility, and the activity of thought, is hinted at in Locke, though the real weakness and one-sidedness of his doctrine has its origin in his neglect of this distinction. Another important distinction, that is drawn by Locke, is that between sensations and the real, essential qualities of bodies, or the distinction between qualitates prim arise and secundaria. If we can only learn by experience of the external world as much as affections of our senses tell us, it becomes a question how much of the data of experience is due to this subjective element, and must be allowed for accordingly, if we wish to attain to knowledge of the thing as it is in itself It is obvious, for instance, that the sweetness of honey exists in o^^r palate, not in the honey itself; heat, light, colour, sound are only feelings in me, not qualities in things, and can only be regarded as the effects produced by them on my organs of sense. What then are the qualities per- taining to things in themselves, which constitute tlieir nature and being 1 Obviously those primary and original qualities which are inseparable from the idea of matter, which are the same under all circum- stances and present in the smallest atoms, that is to say, solidity, extension, figure, position and number of parts, motion, &c. ^ ' The ideas of primary qualities of bodies are resemblances of them, and their patterns directly exist in the bodies themselves ; but the ideas, produced in us by these secondary qualities, have no resemblance of them at all. There is nothing hke our ideas existing in the bodies themselves. They are in the bodies, we denominate from them, only a power to produce those sensations in us, and what ' Essay i. cap. 8. §§ 11-15. LOCKE. 237 is sweet, blue or warm in idea, is but the certain bulk, figure and motions of the insensible parts in the bodies themselves which we call so.' We see here how Locke bridged the passage from the sub- jective or represented to the real world ^ And this separation also was a prelude to the great leading idea of the Kantian Criticism. The ideas of sface and time are carefully weighed by Locke, and the fundamentally erroneous identifi- cation of matter with space extension, introduced by Descartes, is set aside. Locke substitutes for it the idea of solidity ^, which 'we receive by our touch, and which arises from the resistance which we find in body, to the entrance of any other body into the place it possesses, till it has left it. There is no idea, which we receive more constantly from sensation, than solidity. . . This, of all other, seems the idea most intimately connected with and essential to body.' But space and solidity are distinct ideas, as are body and extension. Space therefore may be imagined ' either as filled with solid parts, so that another body cannot come there, without displacing and thrusting out the body that was there before, or else as void of solidity, so that a body of equal dimensions to that empty or pure space may be placed in it, without the removal or expulsion of anything that was there.' Space, time, and number are three simple stock ideas, capable of endless modifications, from which accordingly innumerable modal ideas can be derived. We obtain the idea of space by means of sight and touch ; every measure within it may be conceivably ^ ' Solidity, extension, figure, motion, and rest would be really in the world, as they are, whether there were any sensible being to perceive them or not.' Essay ii. cap. 21. § 2. '^ lb. cap. 4. § i; cap. 13. § 11. 2 ^8 MODERN PHILOSOPHY. •J increased, and it leads thus to the idea of infinity. The position of an object can only be determined in relation to something else ; the place of the universe cannot be determined, it is identical with formless, im- measurable space. Without space naturally neither solidity nor motion are possible, but the latter, the true qualities of matter, differ toto caelo from space. Material atoms may be divided and moved in various ways : it is as impossible to divide space in reality as in imagination ; to consider portions of it apart is not separation. The parts of space are Hkewise im- moveable. But to the question, whether space then is substance or accident, there is no shame in replying, We do not hnoiv. Only let all beware of the mislead- ing sophistries in which one is entangled if one becrins to take words for things. It is equally hard to say what time is. St. Augus- tine's answer to the question is clever : ' Si rogas quid sit tempus, nescio, si non rogas, intelligc' We reach the conception by reflecting upon our feelings and thoughts in the order in which they succeed each other in the mind : without enduring perceptions, we should not have the idea of duration or time. The idea of succession cannot be derived from motion; on the contrary, the latter has to be translated into a mental sequence. The succession of feelings or thoughts always occupies a perceptible portion of time, even when its rapid passage leaves us uncon- scious of the fact, while the movement of the hour- hand or the growing grass is too slow for us to ob- serve. Time and its measurement are something different. Time in itself always follows the same even, uniform course. But we can never say of any particular measure that we adopt, that its parts or periods are perfectly equal. Certain irregularities LOCKE. 239 have been detected m the motion of the snn, which passed for so long as the most reliable measure of time. The movements of the pendulum also are subject to variations arising from unknown causes. It is not possible to prove with absolute certainty the exact equality of two immediately successive periods, and we have to rest satisfied with apparent equality. The idea of time, like that of space, conducts us ne- cessarily to that of infinity, i. e. to the idea of eternity. The idea of time, then, also springs from the two universal sources of knowledge, feeling and reflection. The disappearance and return of ideas in the mind gives us the notion of succession ; the pei-ception of identical existence, by the abstraction of these repre- sentations, gives us the idea of duration, while by unrestrained addition and multiplication of this given duration we attain the idea of eternity ^- Time and space have much in common : both are infinite and cannot be limited by the woild of matter. It is always possible to think away bodies and motion, but the most perfect mind would be unable to con- ceive limits to space and time. I can imagine space without bodies, but I cannot imagine the non-existence of space. The portions of time and space which we assign for the measurement of things are only dis- tances in the boundless uniform ocean of eternit}^ and infinity. Everything has its when and where, in relation only to other known existences. Time and space consist indeed of parts, but are reckoned as throughout of similar nature and as simple ideas ; each portion of time is itself time, each portion of space, space. We have as little conception of their smallest atoms as of their limits, we can always diminish or increase the unit thought of. The parts ^ Essay ii. cap. 14 and 17. 240 MODERN PHILOSOPHY. of both are absolutely indivisible ; continuitj is a necessary property of space and time. The differences are that space extends itself in all directions, while time has only one dimension. The present moment is the same for all things, while no two things occupy the same space. As the parts of time are incapable of permanence, so are the parts of space of succession ^ . But of all ideas, there is none so simple, so famihar, and so peculiar to humanity as that of unity and number. Angels and men, objects, thoughts, things temporal and extended, aU are united in number. Everything that the senses and the ideas derived from them are unable to grasp, on account of its im- perceptible or overwhelming size, becomes fixed and definite as soon as it is conceived numerically, and here no limit is assigned. Numeration consists only of addition and subtraction, and both operations may be continued to infinity. Words seem even more necessary and indispensable for numerical combma- tions than for the formation of any of our other ideas: to a tiibe that has no word for six, everything above five appears as an indefinite many, and the difficulty, which children have in learning to reckon, arises partly from inability to group their ideas in the strict logical order which has to be estabHshed among ideas of number -'. The infinity of space and time and the infinite divisibility of matter depend upon this unbounded power of addition and subtraction. Such infinity transcends all human comprehension. Hence the existence of God, who fills the infinite space and en- dures throughoiit eternity, is an object of faith only. For our reason eternity and infinity are negative ideas, ' Essay ii. cap. 15. ^ lb. cap. 16. LOCKE. 241 and the attempt to give them positive significance 'has only resulted in controversy and contradictory opinions, since our limited powers of comprehension fail before the overwhelming elevation of the objects In regard to the idea of Force, Locke was still much under the influence of the Cartesian distinction. The modifications of things lead us to assume every- where active and passive potentialities. Properlv speaking, matter is wholly passive, while the supreme iafinite mind is everywhere active. We cannot ac- quire the idea of action from sensation, but from reflection, for there are in general two kinds of action only, motion and thought. The idea of thought cannot possibly be derived from bodies, and as for motion, bodies always receive it from without ; it is therefore passive rather than active. For even when one body imparts to another the movement it has itself received, this only spreads and communicates what the body had passively received. Sensation gives us therefore a very obscure impression of the first beginning of action, as the origin of motion. If we attend to the processes of oiir own mind, we see much more clearly and accurately that it is tve our- selves that originate and continue thought, that we ourselves produce or arrest various kinds of motion, in accordance with our thoughts, in other words, accord- ing to our arbitrary choice. The understanding is the faculty of perception and intelligence, but the power of self-determination towards motion or rest, thought or no thought, is called will. We must however be on our guard against assuming the existence of separate activities or regions of the mind, corresponding to these names. The power of acting, in accordance with one's own 1 Essay ii. cap. 17. VOL. I. K 242 MODERN PHILOSOPHY. choice or mental inclination, is called liberty. Its opposite is not necessity, but tlie Avant of freedom : for if I will what is necessary, I am free. The soul, when awake, is always thinking something ; it is free in so far as it is able to direct and concentrate its thoughts and order them in regular sequence towards what is agreeable to it. So far as a man's power of acting or not acting, in accordance with his own thought and choice, extends, so far extends his freedom. Freedom thus concerns action only, not will. It is a direct con- tradiction to speak of the freedom of the will. What manner of thing could that be which had equal free- dom to will and not to will \ Clearly a monstrosity, a chimsera. On the contrar)^, the more precisely the will is determined or conditioned, the more it struggles after freedom and the less it submits to be determined from without \ Locke also wrestled gallantly with the idea of substance, showing it to be an obscure, unknown something, in which we combine a particular aggre- gate of qualities or predicates. If any one inquired what is the subject in which this weight and that colour reside, and was told. These solid and extended parts — he might ask again, What is the subject of these extended parts 1 which would place us in the same difficulty as the Indian, who, after saying that the world rested on the great elephant and the elephant upon a great tortoise, could only suppose the tortoise to rest on ' Something, I know not what.' We are like children, and always seek some substitute, when clear ideas fail us. ' Material substance ' and ' immaterial substance ' are something which we imagine underlying and sup- porting, now the sensible, perceptible properties of ' Essay ii. cap. 21. LOCKE. 243 external objects, now the forms of consciousness whicli we perceive in ourselves. But what this thing may be, we know as little in the one case as in the other. Forces and eflPects constitute the major part of our ideas of substance : the magnet draws the iron, the fire melts the gold ; and the simple ideas of thought, wUl, etc. are as clear as those of solidity and extension. But we know as httle about the nature of material substance as of the substance of mind. The qualities of bodies, such as cohesion and weight, are just as in- comprehensible as the thought and will of the mind ; and the simplest mechanical 23rinciple of the com- munication of motion by impulse from one body to another, is equally incomprehensible. On the other side, however, though we cannot possibly conceive the production of the effect, we have constant ex- perience of all our voluntary motions, as produced in us, hy the free action or thought of our oivn minds only^ It should therefore be considered, whether it is not the nature of spirits to be active, and of matter to be passive. And as all created spirits are at once active and passive, it might be con- jectured that ' created spirits are not totally separate from matter ^.' In a word, all oiir ideas of substance are but ' col- lections of simple ideas with a supposition of some- thing to which they belong and in which they sub- sist;' and most of the simple ideas that make up our complex ideas of substances, are not positive qualities, but ' powers,' a fitness or capacity to operate and be ' An easy leap across the gulf created by Descartes, which sounds at least like a relapse into the old errors. ^ Essay ii. cap. 23. § 28. The Leibnizian doctrine of monads is clearly anticipated here. R 2 244 MODERN PHILOSOPHY. operated on by various other substances (relativity, causal relation). These short extracts will suffice to mark Locke as a worthy fore-runner of Kant. He led vigorous on- slaughts against the strongholds of the ancient dog- matism, and that at the very points where Kant was to force an entrance afterwards. Locke shook the walls, Kant laid them in ruins. Locke proclaimed the impossibility of forming any clear idea of substance in general ; he insisted upon space, time, and causality as the most important elements of human knowledge, a recognition which virtually establishes the relativity of knowledge ; and he proceeded lastly to trace back all our knowledge to sensation and reflection, and to propose the origin of ideas as the chief problem of philosophy. In all this he was reintroducing into philosophy a principle which had threatened to disappear altogether before the doctrine of substance, and especially of the una substantia of Spinoza, namely, the principle of indi- vidual existence. It is not substance that thinks, but the individual being, opposed to the whole re- maining universe, and receiving it into his conscious- ness by sensation and reflection — man himself The Self of a thing is that proper particular exist- ence of it in space and time whereby it is absolutely separated and distinguished from other things ; as a unit. This applies to finite things. The existence of God, without beginning or end or limit, can have no relation to space or time. But everything except God, whether bodies or spirits, must have a definite beginning in time and space, permanence, uaity, con- ditioned throughout in time and space, an untransfer- able existence of their own : all this is the jprincijyiiim individuationis. In the case of composite things it is LOCKE. 245 necessary to distinguisli carefully what it is that pro- perly constitutes their unity. A mere mass consists simply of so many material atoms, and continues the same however differently they may be intermingled, hut it is quite otherwise with the unity of organisms, plants, or animals. In these the material particles change continuously, there is continuity and com- munity of life, of organic movements or functions. Personal identity consists of continuity of con- sciousness, whereby a rational being can bring his present existence into connection with his former action and thoughts, and consider itself as itself, the same thinking thing in different times and places. The question about substance is thus quite indif- ferent. Continuous consciousness, whether it sub- sists in one and the same undivided substance, or in several substances, received successively into the organisation, this alone is the essence of pei'sonal identity. Just as animal identity exists, notwith- standing the continuous change and succession of the material particles which compose the animal body, so personal identity may be preserved through similar succession and change of substance. Besides, why may not several particular spirits unite together to make up one single consciousness, as many particular bodies are united to build up a common life. Person is a judicial term, and personality the foundation of all responsibility. Every action outside the present moment must, in so far as the doer is to be held accountable for it, be brought into the unity of con- sciousness, and be recognised by himself as belonging to him, and so united with his actual self ^ This im- portant and new manner of view is completed and developed in the philosophy of Leibniz. ^ Essay ii. cap. 27. 246 MODERN PHILOSOPHY. We now come in conclusion to Locke's liigliest and most admirable merit, his insight into the nature of general ideas, and the connection between the latter and language. The faculty of abstraction and the general ideas arising from it are proper to man alone and form the true nature of his reason. Abstraction is the faculty of generahsing under a certain name the ideas received from single things. Everything that has to do with the real existence of these single things, such as time and place and other concomitant qualities, must be separated, and the idea alone presented to the understanding apart, and made applicable, under a particular name, to all the things in which it is met. The same colour which I perceive here in milk, there in snow, becomes under the name white a general idea for all things in which this colour may at any time be found. Even if it might be doubted whether animals do not, up to a certain point, combine and extend their perceptions, this faculty of abstraction at all events constitutes a great advantage or superiority possessed by man. As animals have never been known to make use of words or other signs to express any kind of general idea, it is impossible to conclude otherwise than that they are destitute of the power of forming general ideas by abstraction. Imperfection of the organs cannot be the cause of the want of speech, for many animals can articulate several words quite clearly, and a man who, through imperfection of the organs, is unable to speak, finds means of expressing certain general ideas by the use of other signs. Perhaps the true and peculiar distinction between the human species and other animals consists in this faculty of abstraction. Among other animals the LOCKE. 247 activity of the mind is restricted within the narrow circle of isolated impressions from external objects, and their ideas are incapable of widening by abstraction. But the origin of all general ideas is to be found in sensible perceptions \ The simple ideas thence de- rived cannot be defined. No explanation will convey any idea of colour to the blind. Words cannot help, for they are only sounds. To endeavour with words to make any one, who has not had experience of the sensations, realise the taste of an apple, or its red and white colour, is the same as trying to make sound visible and colour audible, or rather to make hearing a substitute for all the other senses, so that we should taste, smell, and see with our ears. All immaterial ideas are originally taken by metaphor from ideas of sensible perception^. The things themselves, and the ideas which we have of them and which we characterise by general names, are naturally altogether different. The former are real, the latter nominal essences. Gold is to us something yellow, heavy, solid, — but we are far from exhausting its inner qualities by this conception. How different is our idea of man from the real being. If I had such an idea of man as the divine Artificer, who beholds all the inmost springs of his bodily and ' Essay ii. cap. 2. Cf. Schopenhauer (Welt als Wille und Vor- Btellung, i. p. 48) : ' Although conceptions differ fundamentally and materially from sensible intuitions, they stand in a necessary re- lation to the latter, without which they could not exist, a relation which accordingly makes their whole nature and essence. Eeflection IS necessarily an imitation, a repetition of the primitive images of the world of intuition, though an imitation of an unique kind in a wholly heterogeneous material. The whole world of reflection rests upon that of intuition as its base.' ^ Essay iii. cap. 3 and 4. Compare with this the observations of Max Mailer (Lectures on the Science of Lang-uage, ii. 372, ninth ed.). 248 MODEEN PHILOSOPHY. spiritual nature, this would bear the same sort of relation to my present notion as the conception of the artist who executed the Strassburg clock does to that of the peasant who stands gaping at it from below. The true reality of things, the so-called formie siibstantiales themselves must always remain incomprehensible to us. In nature herself there are innumerable transitional links connecting different species, which escajoe us, but which make a con- tinuous chain from the lowest inorganic being up to man. We only classify them according to the predicates and qualities which we regard as belong- ing to the essence of each, without knowing whether they are so really. A question which has to be answered in reference to all classification according to genera and species is this : Was it the intention of nature to elaborate her works according to a definite number of unalterable forms or types, and is this number really continuously maintained throughout the production of things ? As long as this question remains unanswered, our classi- fications cannot be founded upon realities, but are only arranged in accordance with certain sensible phenomena. The difference between real and nominal essence is indicated by language. I can say. An extended solid body moves, but I cannot say. Extension and solidity move, though my conception of body includes no other predicates than these. Similarly I can say, A rational animal is capable of sociability and speech, but not, Reason and animality are capable of sociabi- lity and speech!, q^j, thought therefore, as embodied in language, distinguishes itself between the abstract and the concrete. ^ Essay iii. cap. 6. LOCKE. 249 Things are held together in nature by the unity of their essence, as their different quahties, are held together by our conception in the unity of thought. The things themselves, too, are types which we en- deavour to embrace in our general ideas, without however succeeding in ever reaching their individual- ity. Ideas of mixed modes, on the other hand, may include the utmost variety of objects, furnished by the widest experience. 'What a vast variety of different ideas does the word triumphus hold toge- ther and dehver to us as one species !' and so of procession, inquisition, and other words of the same kindi. The following acute remark, if logically followed out, would have led to very important conclusions : 'From what has been before said, we may see the reason why, in the species of artificial things, there is generally less confusion and uncertainty than in natural species. Because an artificial thing, being the production of a man, which the artificer designed, and therefore well knows the idea of, the name of it is supposed to stand for no other idea, nor to import any other essence, than what is certainly to be known and easy enough to be apprehended. . . . Why should we not think a watch and pistol as distinct species one from another as a horse and a dog, they being expressed in our minds by distinct ideas, and to others by distinct appellations"?' The conclusion that the earliest and most natural ideas of men, and so also their earliest vocal expressions, must have originated from their oivn creations might have been deduced from this observation. In another passage too Locke seems to skirt unconsciously the edge of the discovery that language originated from action, and 1 Essay iii. cap. 5. ^ II^. cap. 6. § 40, 41. 250 MODEKN PHILOSOPHY. more particularly from common action. ' It is worth our observing,' he says, ' which of all our simple ideas have been most modified, and had inost mixed modes made out of them, with names given to them ; and those have been these three ; thinking and motion (which are the two ideas which comprehend in them all action) and power, from whence these actions are conceived to flow. . . . For action being the great business of mankind, and the whole matter about which all laws are conversant, it is no Avonder that the several modes of thinking and motion should be taken notice of, the ideas of them observed, and laid up in the memory, and have names assigned to them ; without which laws could be but ill made, or vice and disorder repressed. Nor covild any com- munication be well had amongst men, without such complex ideas with names to them^' The following remark is equally profound, that ' many words which seem to express some action, signify nothing of the action or modus operandi at aU, but barely tlie effect. . . . When a countryman says the cold freezes water, though the word freezing seems to import some action, yet truly it signifies nothing but the effect, viz. that water, that was before fluid, is becom.e hard and consistent -.' Locke begins by professing his own ignorance ' how the ideas of our minds are framed, of what materials they are made, whence they have their light, and how they come to make their appearances,' and appeals to experience as his only guide ; but tliis initial doubt prevailed on him to direct the illumina- ting power of his genius towards this obscure region, in which he cast new and important light upon the origin of ideas, or the function of the thinking ^ Essay ii. cap. 22. § 10. ^ lb. § 11. LOCKE. 251 faculty, so furnishing at once guidance and material for future enquirers. Language and ideas are thus the two inestimable means of all human knowledge. But in them too and their imperfection the true causes of most errors, false or premature opinions, and endless em- bittered and profitless controversies, are to be found. Among these causes the first and most important is, that the majority of men imagine that whenever a word has been given them, a suificient explanation has been given also. Instead therefore of subjecting the content of the idea to a careful examination, they utter like parrots the words they have glibly learnt from childhood, and do not think at all. To this must be added the difficulty, not to say impossibihty, of securing that two men shall think the same thing, when using the same words. No man has the power to make others have exactly the same ideas in then- minds that he has, when they use the same words that he does. In regard to the most important ideas, those of morals, do not we learn the words before we have the least con- ception of the things, and then afterwards join to them some idea as best we can ■? Hence the endless disputes about religion, faith, grace, etc., while every one believes he must make his own ideas, clear or hazy as the case may be, the standard of the meaning of the words. Most of those who are readiest to dispute about religion and con- science, chiirch and creed, might and right, would be silenced if they were summoned to keep to the matter and not to words with which they perplex themselves and others. Most controversies are mere logomachies, in which each side thinks something different or nothing at all cqorojMs of the words they 252 MODERN PHILOSOPHY. agree in using. By paying close attention to the meaning and the matter itself, without attaching themselves to words and names, men would soon come to an understanding, were it not that passion and interest withhold them from confessing the truth. Language ought to serve for the acquisition of know- ledge and its ready communication. Words without clear and definite ideas are empty sound. And he who did but fill folios with obscure, unintelligible words, would gain as little knowledge as any one who studied the titles and not the contents of the books in a large library. Language and ideas belong es- sentially to one another. ' He that has complex ideas, without particular names for them, would be in no better case than a bookseller, who had in his warehovise, volumes, that lay there unbound, and with- out titles which he could therefore make known to others only by showing the loose sheets, and can communicate them only by tale^.' The man is un- able to communicate his complex ideas for want of words, and therefore has to use words for all the simple ideas which go to make up the complex one. Locke also pronounces a severe sentence of con- demnation upon 'the obscure and unintelligible discourses and disputes ' of scholastic philosophy, words of righteous indignation which are just as crushingly ajoplicable to modern scholasticism as to that of the Middle Ages. He speaks of the practical inutility of the 'curious and inexplicable web of perplexed words ' with which these profound doctors win commendation, all the more becatise they could ' Essay iii. cap. lo. § 27. Kant has used the same image to illustrate the relationship of ideas and intuitions. The same idea was clearly floating in Locke's mind, though he thought of ideas instead of intuitions, and words instead of ideas. LOCKE. 253 not be understood, and continues : ' Nevertheless, this artificial ignorance, and learned gibberish, pre- vailed mightily in these last ages, by the interest and artifice of those, who found no easier way to that pitch of authority and dominion they have attained than by answering the men of business and ignorant with hard words, or employing the ingenious and idle in intricate dispute about unintelligible terms, and holding them perpetually entangled in that endless labyrinth : . . . retreats more like the dens of robbers or holes of foxes, than the fortresses of fair warriors ; which if it be hard to get them out of, it is not for the strength that is in them, but the briars and thorns, and the obscurity of the thickets they are beset with. For untrvith being unacceptable to the mind of man, there is no other defence left for absurdity, but obscurity ^.' One of the greatest and commonest sources of error, which seems almost unavoidable as long as human thought is associated with words and ideas, lies in the confusion of words with things, i. e. the illusion that there must necessarily be a self-subsisting reality corresponding to the word. Thus the Peri- patetics take their substantial forms, their vegetative souls, the horror vacui, and even the categories for actual beings, while the Platonists did the same with their ideas, and the other sects with their fundamental principles. ' How many intricate disputes have there been about matter, as if there were some such thing really in nature, distinct from body!' and yet this distinction only exists in our imagination, for ' body stands for a solid, extended, figured substance, whereof matter is but a partial and more confused conception, leaving out extension and figure.' The principal ^ Essay iii. cap. lo. § 8, 9. 2 54 MODERN PHILOSOPHY. cause of this eternal error is — as Locke acutely saw — tradition. It would be difficult to persuade any one that the words which were used by his father or schoolmaster, the parson of the parish or some reverend doctor, signified nothing that really existed in nature \ The method of the schools, to lay down the most general principles, and then to deduce the rest from these, as from eternal truths, is uncongenial to Locke. Nothing, he holds, can be inferred from these proposi- tions; everything turns upon the correctness of the ideas involved in them. The principle of identity (what is, is) and of contradiction (the same thing cannot at the same time both be and not be) may lead in that way to the most contradictory results. If any one agrees with Descartes in defining body to be nothing but extension, he may easily demonstrate that there is no vacuum (i. e. no space void of body) by the maxim what is, is ; but if the note of solidity is added to the conception of body, the existence of space without body will be as easily demonstrated as the contrary was by Descartes ". All these principles, which are extolled as the bulwarks of truth, can afford no protection against errors arising from the careless or confused use of ideas. Locke's endeavour was to give in all cases a fixed and definite sense to the ideas which have been handed down to us by the tradition of generations and by means of language, and which have been so far obscured and confused by the countless accidents attendant on their origin as to be unavailable for philosophic use without such revision. A profound insight into the nature of speech and reason must convince us that this is impossible to a single mind, ' Essay iii. cap. lo. § 15, 16. '' Essay iv. cap. 7. § 11, 14. LOCKE. 255 that in fact our whole thought is bound up with these forms, and accomplishes itself according to them by a kind of natural necessity, so that it is only a matter of development, of slowly ripening in- telligence, when tlie human mind frees itself grad- ually from the prejudices and conceptions of the past, and substitutes for its former childish Logic, which contained all the truth then accessible, a purified, more adequate, self-conscious logic of ideas. The solar wheel which, revolving in or with the heavens, was for long millenniums among the most certain facts of the primitive races, — the chariot of the sun, driven by Helios above the brazen vault, succeeded it ; — then a vast fiery disk, and, lastly, a huge central body round which our earth revolves, held by the invisible band of attraction. And now we have to confess that this last power, attraction, is no more intelligible to us to-day than the divinities of the past, and will have no doubt in time to make way for a clearer and more complete conception. Thus the growth, reformation, and transformation of ideas, constitutes itself the very process of rational develop- ment. We, however, whether we choose or no, are subject to this rule, and the sum and substance of all the ideas of a period is only the expression of the prevailing view as to the world at large. The great problem of the connection and relation between the spiritual and the material world is likewise touched upon by Locke and expounded upon Cartesian principles : ' All power relating to action, and there being but iivo sorts of action, whereof we have any clear idea, viz. thinking and motion ; let us consider whence we have the clearest ideas of the powers which produce these actions. Of thinking, body affords us no idea at all, it is only from reflection 256 MODERN PHILOSOPHY. we have that ^.' ' There are but two sorts of beings in the world, that man knows or conceives. First, such as are purely material, without sense, perception or thought. Secondly, sensible, thinking, perceiviag beings, such as we find ourselves to be. . . . It is as impossible to conceive, that ever bare, incogitative matter should produce a thinking intelligent being, as that nothing should of itself produce matter. . . . Matter by its own strength cannot produce in itself so much as motion : the motion it has must also be from eternity, or else be produced and added to matter, by some other being more j)Owerful than matter ; . . . yet matter, incogitative matter and motion, whatever changes it might produce of figure and bulk, could never produce thought. ... If we suppose bare matter, without motion eternal ; motion can never begin to be ; if we suppose only matter and motion first, or eternal ; thought can never begin to be ^.' But if we suppose matter itself to be cogitative, fresh difficulties arise, for the question presents itself, whether every particle of matter thinks? And if this is denied, the unanswerable question remains, 'how a composition of jsarticles of matter, each whereof is incogitative,' is to form a whole, possessing the faculty of thought. The only remaining hypothesis is that of an eternal intelligent Being, who has created matter out of nothing. If it is objected that we cannot conceive this, he replies, neither can we conceive how our bodily limbs are moved by our own will. ' This is matter of fact which cannot be denied : explain this and make it intelligible, and then the next step will be to understand creation. For the giving a new determination to the motion of the animal spirits (which some make use of to explain ^ Essay ii. cap. 21. § 4. ^ Essay iv. cap. lo. § 9, 10. LOCKE. 257 voluntary motion) clears not the difficulty one jot. . . . If you do not understand the operations of your own finite mind, that thinking thing within you, do not deem it strange that you cannot comprehend the operations of that eternal, infinite mind, who made and governs all things, and whom the heaven of heavens cannot contain ^.' Here Locke, Hke all other philosophers, resorts to the Deity, who accomplishes the miracle which to us is incomprehensible. But in another passage which has called forth loud and repeated eulogy from Voltaire, and violent attacks from bigots, he admits the possibility of matter being endowed by God with the property of thought : ' We have the ideas of matter and thinking, but, possibly, shall never be able to know whether any mere material being thinks, or no. . . . We know not wherein thinking consists, nor to what sort of substances the Almighty has been pleased to give that power, which cannot be in any created being, but merely by the good pleasure and bounty of the Creator. For I see no contradiction in it that the first eternal thinking being should, if he pleased, give to certain systems of created matter, put together as he thinks fit, some degree of sense, perception, and thotight. . . . What certainty of knowledge can any one have that sense-perceptions, such as e. g. pleasure and pain, should not be in some bodies themselves, after a certain manner modified and moved, as well as that they should be in an immaterial substance upon the motion of the parts of body ■? Body as far as we can conceive, bemg able only to strike and affect body; and motion according to the utmost reach of our ideas, being able to produce nothing but motion; so that when we ^ Essay iv. cap. 10. § 18, 19. VOL. I. rf 258 MODERN PHILOSOPHY. allow it to produce pleasure, or pain, or the idea of a colour or sound, we are faia to quit our reason, go beyond our ideas, and attribute it wholly to the good pleasure of our Maker. ... It becomes the modesty of philosophy not to pronounce magisterially, where we want that evidence, that can produce knowledge. And therefore it is not of such mighty necessity to determine one way or the other, as some over-zealous for or against the immateriality of the soul have been forward to make the world beheve. Who either, on the one side, indulging too much their thoughts, immersed altogether in matter, can allow no existence to what is not material ; or who on the other side, finding not cogitation within the natural powers of matter, examined over and over again by the utmost intention of mind, have the confidence to conclude that omnipotency itself cannot give perception and thought to a substance which has the modification of. solidity. He that considers how hardly sensation is, in our thoughts, reconcileable to extended matter ; or existence to anything that hath no extension at aU, will confess that he is very- far from certainly knowing what his soul is. It is a point which seems to me to be put out of the reach of our knowledge. . . . Since on whichever side he views it, either as an unextended substance, or as a thinking, extended matter ; the difficulty to conceive either, will, whilst either alone is in his thoughts, still drive him to the contrary side. An unfair way which some men take with themselves who, because of the unconceivableness of something they find in one, throw themselves violently into the contrary hypothesis, though altogether as unintelligible to an unbiassed understanding ^' ^ Essay iv. cap. 3. | 6. LOCKE. 259 This argument serves Locke as an illustration to prove that our knowledge is limited, not only by the scanty number and imperfect nature of our ideas, but also by its failure to come up even to these. On the contrary, in the attempt at their application we become entangled in doubts, difficulties, and con- tradictions. Locke might have drawn hence the conclusion that the merely empirical origin of our ideas was not to be accepted unreservedly, since mere experience, even in the condensed form of ideas, can never fall into self-contradictions. Some other ele- ment must therefore enter into the formation and comparison of ideas, some interpreting and explaining faculty must co-operate, the unconscious postulates of which are the subject of metaphysics. The in- compatibility of the ideas dealt with here may however be easily explained. It proceeds from the fact that something has been included in each of the con- ceptions which the other absolutely excludes. Locke conceived matter as extended, consisting of parts, moveable, passive, and mind as alone consciovis, thinking, perhaps also moving, in any case active. Such ideas must naturally and for ever exclude each other. Truth can only be reached when it is seen that thought has separated, by abstraction, what in reality never appears as separate, or in other words, that not one of our ideas corresponds to a true reahty, but that aU are woven with a woof of ideality. Locke did not go beyond this modest attempt to assert the possibility that a material being might at the same time be a sensitive one. Indeed he seems to have looked with surprise at his own audacity, for in the tenth chapter of the same book he weakens the force of his argument by proving the opposite. To sum up once more the great achievements of s 2 26o MODERN PHILOSOPHY. this fertile and vigorous thinker, we have to reckon as real and novel additions to the store of philosophic consciousness, — 1. The empirical, observant study of the human reason, as the gift most characteristic of mankind and the source of all higher knowledge. The per- ception that general ideas are the true objects of the reason ; that they originate natvu-ally, and are jjerfected in men by abstraction ; an intimation of the connection between them and language ; the statement of the problem as to the origin of these ideas ; the tracing them back to sensible impressions, and the indication of the connection between sense and reason. 2. From what has been said, it follows that the individual thinking man is the true subject of all knowledge. All his ideas and thoughts proceed equally from individual perceptions or contact with the external world. The necessary limitation of aU knowledge follows. To appreciate the new truths at both these points it needs but to contrast the undeterminate sub- stantia cogitans with its innate ideas and eternal truths. The reality of the individual is maintained in contradistinction to the mere mode of Spinoza. The idea of development becomes possible, as the reason obviously passes through a course of develop- ment. And thought, represented by Spinoza as ac- complishing itself by the same strict causal laws as everything else in mind and body, was fertihsed and vivified by the recognition of laws and functions pro- per to itself. 3. The idea of sid)stance was shown to be in- accessible to human knowledge, and its origin was referred to the nature of thought. LOCKE. 261 4. The distinction between our sensible impres- sions and the true qualities of objects, between quali- iates primarise and secundaria}, points the way to the future distinction between things as thought or imagined, and things by themselves. The gaps and imperfections of the Lockian doctrine are : — 1. The hesitation between individualism pure and simple, which can only conceive things as they are given by the senses and imagination \ and can there- fore never go beyond its subjective standpoint, and the assumption of an objective woi'ld, actually existing in itself in space and time. 2. This indecision prevented Locke from entering upon a more thorough investigation of the nature of reason, and showing what is originally proper to reason and what nature and characteristics have grown up and been developed through the reception of sense-impressions. To Locke the mind appeared as an originally dark room, into which rays of light from the outer world penetrate by certain rifts and cracks, and so increase and complete the thinking faculty. The active side of this faculty, however, is much neglected and often wholly overlooked, while the analysis of reason has obviously to occupy itself most with this ; the nature of the senses and conjec- tures as to the true nature of the outer world being of comparatively little consequence. 3. Thus the whole function of thought and rational ' ' I, as an indiyidual, am fixed and determined as the subject of knowledge, and it is impossible that I should know the finite object in itself, much less the infinite. I can only know either of these indirectly, in so far as they come within the range of my con- sciousness, in so far as they are represented in my sensations and my thoughts.' 262 MODERN PHILOSOPHY. knowledge appears as a process effected from and by the world of sense without. 'According to Locke, the real, i.e. matter, generates images or the ideal in the knowing mind by impulse or shock. We have thus here a fine massive realism, which, pro- voking contradiction by its very exorbitance, occa- sioned the idealism of Berkeley ^' And as Locke, in accordance with his strict empiricism, represented the law of causality itself as a discovery from experience, he suggested Hume's doubt, who declared the whole causal conception to be unreal and naught, and so in his turn gave occasion directly to the profound investigations of Kant. 4. Locke's profound and important view that general ideas are the true objects of thought was not as much utilised and developed by him as the importance of the subject and the simplicity of the principle allowed and required. It was necessary, and he himself held it to be the chief task of philosophy, to examine carefully into the origin of ideas, and that not only by means of sensible perceptions or self-observation ; the origin of ideas from preceding ideas as revealed in the history of human language should have been set forth too. It is true that in the age of Locke such an undertaking would have been difficult, not to say impracticable, as the Science of Language as yet was not. Otherwise Locke would have had to surrender his erroneous belief that man can form ideas without words, and that the latter are only conventional signs for ideas already existing in thought^. Clearer knowledge on this point would have en- abled Locke to define the concepts of thought and ' Schopenhauer, Parerga, i. p. 16. ^ See Max Muller, Lectures on the Science of Language, ii. p. 75. LOCKE. 263 of ideas far more sharply, and he would not then have ascribed to mere sense-impressions the character and value of ideas. ' It is certain that the mind is able to retain and receive distinct ideas long before it has the use of words, or comes to that, which we commonly call the use of reason. For a child knows as certainly, before it can speak, the difference be- tween the ideas of sweet and bitter (i. e. that sweet is not bitter), as it knows afterwards (when it comes to speak) that wormwood and sugar-plums are not the same thing ^.' The discovery that the key to the mystery of thought lies hid in language was not to ripen till a much later day. The first clear indication, besides those given by Geulinx and Locke, is to be met with in Schopenhauer, in various passages of his chief work, Die Welt als Wille und Vorstellung, especially vol. i. pp. 566-70, where he hazards the conjecture that the real categories of thought will be found ia the partes orationis, that is to say in grammar. Very true and pertinent is his observation about Locke (ib. p. 45) : ' It is very surprising that no philosopher has yet traced all the various mani- festations of reason back to one simple function, which might be recognised in them all, by which they might all be explained, and which would there- fore be seen to constitute the proper, inner nature of reason. The admirable Locke, indeed, describes abstract universal ideas quite rightly, as marking the distinction between man and beast, and Leibniz repeats this with complete assent. But when Locke comes, in his fourth Book, to the explana- tion of reason itself, he loses sight of this chief characteristic altogether, and falls into an hesitating, ' Locke, Essay i. cap. i. § 15. Cf. the admirably clear refutation of this view by Max Mtlller, loo. cit. p. 77. 264 MODERN PHILOSOPHY. indefinite, fragmentary expression of incomplete and second-hand opinion, and the same must on the whole be said of Leibniz in the corresponding passage of his work.' At the same time, Locke's intellectual greatness, and the extent of his influence upon the subsequent development of philosophy, is duly recognised by Scho- penhauer, in the following passage : ' Locke was the first to proclaim the great doctrine, that a philosopher who wishes to prove or derive anything from ideas must first investigate the origin of these ideas, as their content and everything thence deducible must be determined by their origin, as the source of aU the knowledge attainable through them.' The history of the develojmient of human ideas is in fact the most important, if not the only task of the philosophy of the future ^ ^ As this truth is still only just beginning to dawn upon the general consciousness, the following utterances of a distinguished thinker, who obviously had some perception of its truth, may be quoted here : 'Locke's Critique of Reason eventuates, accordingly, in a criticism of language, which, according to its leading idea, is of higher value than any other part of his system. The important distinction between the purely logical and the psychologico-his- torical elements in language had the way prepared for it by Locke ; but apart from the preparatory labour of philologists, little material progress has been made since. And yet by far the greater number of the conclusions which are applied in philosophic science only go, as it were, upon all fours because ideas and words are being con- tinuously interchanged.' Lange, Geschichte des Materialismus, i. 2 7 1 . THE INDIVIDUALISTIC TENDENCY. LEIBNIZ (164=6—1716). ' Le grand secret de la vie est la permanence des forces et la mutation continuelle de la matifere.' Flourens, De la Vie et de I'lntelligence. We have seen how in Locke the individual was reinstated in. his rights, the Cartesian starting-point renewed, and the cogito referred with increased clear- ness and precision to human thought properly so called. Our study of the individual thinking man is the source whence all information respecting the value, limits, and origin of knowledge must be derived. Though the matter of knowledge proceeds from particulars, i.e. from single perceptions, enquiry only confirmed the truth enunciated by Aristotle, that thought depends upon general concej^tions, and that accordingly predicates and their combinations constitute the essence of all our intellectual opera- tions. The task which Leibniz proposed to himself was to give the individual a place in the self-subsisting world outside our knowledge, and to attempt an interpretation of the universe in which, starting from individuals and particulars, whose dependence from and co-operation with the whole should be recognised, a certain independence and self-subsistence should also be recognised as constituting their true essence. The individual separate existence of things finds 266 MODERN PHILOSOPHY. its first expression in the atomic theory of De- mokritos and Epikuros. This corresponds to the natural course uniformly taken by the human reason, which always begins by looking for its principles in the objective world, and only discovers at a later time their true source within itself. It is there- fore nothing strange that the multiplicity of sense- perceptions should receive their first explanation from the objective unity of the external world. But what lends its real philosophical value to this idea is the unity of nature, XTnconsciously underlying the multiplicity of individuals and recognised by the process of abstraction, in which reality is conceded only to those sensible quahties of things which admit of quantitative determination, such as form, position, motion, weight. And these are the same qualities which constitute the base of the mathematical view of nature, and form, in other words, the true nature, the qualitates frimarise of matter, recognised by all true science and all later philosophy, including that of Descartes, Spinoza, Locke, Leibniz, and Kant. A thinker hke Leibniz, who early recognised the profound significance of individual existence, was naturally attracted towards the atomic theory, while yet he could not faU to discern its incompleteness, and its collapse at the very point where the real diffi- culties of the philosophic problem begin. From this point of view his own account of his earher days, given in a letter to Eemond de Montmort\ is inter- esting : ' I remember that, for days together, I used to walk up and down in a little wood near Leipzig, called the Ptosenthal, considering whether I should retain the substantial forms. The mechanical view gained the upper hand at last, and led me to mathe- ' Leibnitii Opera Philosophica, ed. Erdmann, p. 702, LEIBNIZ. 267 matics. But when I sought for the ultimate prin- ciple of the mechanism in the laws of motion I returned to metaphysic, from the material to the formal, to the assumption of Entelechies, and at last discerned, after often revising and developing my ideas, that monads, or simple substances, are the only real substances, and that individual things are but phenomena, though indeed well-founded and mutually dependent phenomena/ It is difficult for the present generation to realise the significance of the Leibnizian system. We must recall the vast contradictions and inconsistencies in which human thought had landed itself before him, in order to do justice to his philosophy as the last vigorous attempt at a reconciliation of the real and the ideal worlds, instead of regarding it as a laborious concatenation of self-made difficulties. The antagconism between individualism and uni- versalism gives birth to opposites, which may be tabulated as follows : — Freedom and self-determination Omnipotence and predestination of the individual being. of the Divine Creator. Activity, inner consciousness and Passivity of matter. intelligence. Unity and indestructibility of Infinite divisibility of matter. substance properly so called. Intellectual perception, final Absolute, invariable mechanism, causes. efficient causes. Atoms, according to Demokritos. Substance, according to Spinoza. Leibniz was an exceptionally many-sided thinker, entering, and always with some degree of creative power, upon every field of human knowledge. His attachment to Aristotle has its root in a certain in- tellectual affinity. The resemblance lies in the rest- less genius which illuminates the darkness with its 268 MODERN PHILOSOPHY. flashes and reveals new views and possibilities, but never endures long enough for a complete structure to be developed out of a single principle. Hence with bim, as with Aristotle, repetitions are frequent, and abrupt transitions which disappoint expectation at the most critical moment. Kant says of him : ' The celebrated Leibniz possessed real insight, by the help of which the sciences were enriched, but he was still more fertile in conceptions for the complete execution of wliich the world looked in vain.' With such a temperament it is not surprising if his pre- mises were often vacillating and insecure. He says himself in a letter to Thomas Burnet, after describing his struggles, before deciding between Aristotle and Demokritos: ' Cej)endant j'ai changd et rechange sur de nouvelles lumieres et ce n'est que depuis douze ans environ que je me trouve satisfait.' The name of Leibniz is however indissolubly as- sociated with two ideas, in his own eyes the in- separable parts of a single whole, namely, the doctrme of Monads and the j)re-established Harmony. The former, though only a germ, is a lasting and valuable philosophical possession, of which we shall hardly see the full development until vajious an- tiquated prejudices have passed away. The latter, on the contrary, is a mere dogmatic artifice for evading a question which has been so stated as not to admit of solution. As however often happens,, the father was most attached to his least hopeful offspring, and he was wont, especially in his later years, to return again and again to this favourite error, when ui his controversy with English philosophers he wished to accentuate the agreement between his doctrine and the dogmas of Christiarnty. Leibniz, who was committed to a reconstruction LEIBNIZ. 269 of the real world, logically starts, like Spinoza, from the idea of substance. He summarily dismisses the doubt suggested by Locke as to the justice of this conception. 'The idea of svibstance is not so obscure, he thinks, as people imagine. What is necessary may be known of it as much as of other things ; nay the knowledge of the concrete always precedes that of the abstract ; and people learn to know hot things much earlier than heat ^' This passage would suffice by itself to show that the essential characteristic of substance, that is to say existence, was educed from concrete particulars, or, ui other words, from the individual existence of the human mind, and must consequently reside also in single things. Descartes had laid down that it was necessary in explaining things to revert always to les natures simples ; Leibniz discerns the true substances simples in individual units whose true nature consists in their existence and determination, or, as he puts it in his first Dissertation, in the language of the Schoolmen, ' Omne individuum tota sua entitate individuatur.' He is thus, according to Scholastic ideas, a decided Nominalist, and holds that the par- ticular has a claim to actual real existence. These original units are the monads. The monads are each its own independent world, simple, inde- structible, and exclusive of all remaining existence : their qualities are described as follows. They must be immaterial, for matter is infinitely divisible, that is, destructible, and moreover matter is altogether passive : for action and intelligence to result, it must be penetrated by these infinitesimal, unextended, infinitely numerous units of which per- ^ Nouveaux Essais sur rentendement humain, p. 238, Erdmann. 270 MODERN PHILOSOPHY. ception and will are properties. For it is impossible that merely meclianical causes should produce any- thing like consciousness and perception. The monads might also be called entelechies or souls, but the latter idea is by far the most perfect. The dim conscious- ness which veils our perceptions in syncope may serve as an image of the simple monad ^ It is certain that Leibniz conceived the whole world to be penetrated with these immaterial monads, and, fro tanto, as organic, so that nothing could exist without secret properties, individual character, and self-determination. This at least follows from his expression, ' II faut rdunir Democrite et Spinoza ; ' that is to say, everything is individualised and every- thing is animated. He says in a letter to De Mai- zeaux 2, ' You do not understand what other bodily substances there are besides animals, whose complete annihilation has hitherto been erroneously assumed. But if there are in nature other living organised bodies besides the lower animals, as is very probable, as the example of plants may show, these bodies must also have simple substances or monads, which give them life, i. e. perception and will, although this per- ception need not be sensation. There are obviously an infinite number of possible degrees of perception, and that also among living beings.' Similarly in the Monadologie, he says * : ' There is a world of creatures, of living things, animals, ente- ' Monadologie, Erclmann, p. 706. ^ Opera, ed. Erdraann, p. 676. He expresses his views still more clearly in the letter to "Wagner, Erdmann, p. 466: ' Natura ubique organica est, et a sapientissimo auctore ad certos fines orJinata, nihilque in natura incultum censeri debet, etsi interdum non nisi rudis massa nostris sensibus apparet.' ° Monadologie, §§ 66-70. LEIBNIZ. 271 lechies, souls in the minutest particle of matter. Every part of matter may be considered as a garden full of plants, or a tank full of fishes. But every branch of the plant, every member of the animal, every drop of its juices is again a similar garden and a similar tank. There is thus nothing uncultivated, nothing unfruitful, nothing dead in the universe, no chaos, no disorder. Every living body has a central monad or ruling entelechy, but the members of the living body are full of living things, plants, animals, each of which again has its own entelechy.' When the time comes for describing the connection or concomitance of the monads and the material world, the same obscurity appears in Leibniz as ia Spinoza, when he attempts to explain at once the unity and the independence of the two causal series, of mind and matter (p. 206 ante). The monads with their unextended immaterial nature, endued with perception and appetite, contain the true indestruct- ible essence of substance, and so far Leibniz starts upon the original line of Descartes, according to whom consciousness is the most certain and primitive of qualities, while matter and extension sink into the rank of phenomena. Leibniz frequently expresses himself in this sense, and so to some extent, as Scho- penhauer observes \ anticipates both his own and the Kantian doctrine, 'quas velut trans nebulam vidit.' Thus much is certain, that there can be no direct action of monads upon matter or of matter upon monads, and accordingly an appeal to the Deity as the central monad becomes necessary here. This power has so ordered everything in both worlds from the beginning, that through the whole course of time the correspondence between the two is unfailingly exact, ^ Parerga, i. 80. 272 MODEEN PHILOSOPHY, and eyerj thought or act of will is attended by a modification of material substance, answering to it as if the connection between the two were causal. There are three alternative explanations, as in the case of Leibniz's well-known illustration of two clocks keep- ing exact time together. 1 . That the same mechanism regulates the motion of both : 2. that some one from time to time readjusts their works so as to bring them again into agreement ; or 3. that both were from the first so perfectly constructed as to make divergence impossible. The influxus physicus would correspond to the first case, but is inadmissible, since it is incon- ceivable that miiid shoidd act upon matter or matter upon mind. .The second hypothesis corresponds to the occasional causes of Malebranche and Geuhnx, which presuppose continuous divine intervention; the third hypothesis alone is worthy of the Deity, and this is the doctrine of the pre-estahlished harmony. The points of contact between Leibniz and Des- cartes and Spinoza, as well as those of divergence, are easily visible. The Cartesian cogito involves the purely subjective, individual standpoint of the ego, an intellectual being whose original properties are thought, feeling, and will. As Leibniz, and subse- quently Schopenhauer, used this ego as a key to inter- pret the universe, they necessarily attributed to the innumerable other egos the same attributes that they had met with in their own. Leibniz is thus to a certain extent at one with Descartes and his sub- jective method, and with Spinoza's broad universalism. The latter brings the manifold into unity, treating it as a mere rip])le on the surface, while Leibniz saw always the component units within the manifold ^ ' The metaphor used by Leibniz is charactei'istio of his opposition to Spinoza — that the monads are rays (fidgurations) of the Deity. LEIBNIZ. 273 The Leibnizian theory may thus be described as an exaggerated individualism, Spinoza's doctrine as an extreme universalism. Human thought is carried on within the universe, and is only to be explained by the help of abstraction and opposition, i. e. by indi- vidualism. Hence human thought can never succeed in looking at the world from without, still less has it the right to impose its own nature upon existence and say Deus est res cogitans. But it is a no less capital error to reduce everything to individual ex- istence, and to assume the latter to subsist as an unchangeable entity through all eternity, as if all ideas, strivings, and effects crystallised in unex- tended points, without considering that this indivi- duality itself is a product, — however mysterious and unfathomable one of its elements may be, — of an im- measurable woild of forces around, and an equally immeasurable duration of forms of consciousness and intellectual effort, which must be taken to- gether to account for the present constitution of the individual, its thought, and will, as actually existing. It may be said : Spinoza represents the world as if there were no individuals, Leibniz, on the other hand, as if there were no universals. The former leaves unexplained the way in which particular things detach themselves from the universal sub- stance and assume an independent existence, while Leibniz is compelled to resort to miracles to explain the coexistence and interaction of the monads or in- dividual existences ^ It is the old quarrel between Herakleitos and Demokritos. ' Monadologie, §51:' Mais dans les substances simples ce n'est qu'une influence ideale d'une monade sur I'autre qui ne peut avoir son effet que pas I'interveution de Dieu, en tant que dans les idees de Dieu une monade demande avec raison que Dieu en reglant les VOL. I. T 2 74 MODERN PHILOSOPHY. The opposition between matter and mind is worked out much more profoundly by Leibniz than by Des- cartes. According to the latter, matter is identified with extension, and becomes, together with motion, the object of purely mechanical explanation. Leib- niz, on the contrary, discerns that although motion, as associated with matter, appears to us as passive and mechanical, yet, viewed in itself and traced to its true source or fons mechanismi, there is also an element of activity in it, the interpretation of which is to be sought in our ovm consciousness, and not without. Hence he distinguishes the materia ^rima, to which form is properly opposed, from the materia secunda, which is already moulded. 'Materia est quod consistit in antitypia seu quod penetranti resistit, atque ideo nuda materia mere passiva est^' Bodies possess a certain vis activa apart from matter ; their nature includes some entelechy, soul, or something analogous to a soul. Every monad has an organised body, but there are endless grades of animation, and the lowest escape our observation as infinitely slight movements do. ' Les corps agissent selon les lois des causes efSci- entes ou des mouvements. Les 4mes agissent selon les lois des causes finales par appetitions, fins et moyens. Et les deux rfegnes, celui des causes efEci- entes et celui des causes finales, sont harmoniques autres d^s le commencement des choses ait regard k elle. Car puis- qu'une monade cr66e ne saurait avoir une influence physique sur I'interieur de I'autre, ce n'est que par ce moyen que I'une peut avoir de la d^pendance de I'autre. § 56. Or cette liaismi ou cet accommodement de toutes les choses creees k chacune et de chacune a toutes les autres, fait que ohaque substance simple a des rapports qui expriment toutes les autres et qu'elle est par consequent un niiroir vivant perp(5tuel de I'univers.' ' Epistola ad Bierling, Erdmann, p. 678. LEIBNIZ. 275 entre evix ^.' Everything occurs in the world of mind as if there were no bodies, and in the world of matter as if there were no soul. We may discern here a foreshadowing of the truth that in the slightest and most rudimentary modifica- tions of material phenomena an immaterial principle is involved, which naturally never becomes apparent to the senses, but to which we have a key in ourselves, where we know the same power as consciousness or will. In this way the order of beings, according to their degree of animation, or in other words, according to the elaborateness of their oi'ganisation, with its attend- ant of heightened consciousness, becomes intelligible to us. Leibniz is clear on this point in the letter to Wagner (Erdmann, p. 466) : ' The modifications of the antitypy (impenetrability) are only changes of place, the modifications of extension are only changes of magnitude and form : in all this matter appears as purely passive ; but in motion itself there must reside an internal principle which is quite different from the matter that is moved.' Schopenhauer calls this principle Will, and does not ascribe consciousness to it ; Leibniz, after Aristotle, calls it Entelechy, and sees in it something analogous to the human soul, and therefore some kind of consciousness, which may be conceived at many degrees of illumination ; and, with far more justice than Schopenhauer, he gives it accordingly the name of percep/^'ow. ' I reply, thirdly,' he says, ' that this active principle, this prime Ente- lechy, is in truth also an indestructible vital principle, endued with the faculty of perception. It is this which, in the case of animals, I regard as their souls. In assuming matter to be in aU cases attended with ^ Monadologie, § 79- T 2 276 MODERN PHILOSOPHY. principles of activity, I assume also everywhere vital principles which perceive, or monads, so to speak metaphysical atoms, which are indivisible and inde- structible.' ' As to what regards the soul, this may be taken either in a wider or a narrower sense. In tlie first sense, it is the same as hfe itself, a principle of inward activity existing in a simple thing or monad and corresponding to its external activity. This parallelism between the outward and the inward, or representation of the former in the latter, of the com- plex in the simple, of the many in the one, really constitutes perception, and this is not the exclusive possession of animals, but is shared by all perceiving beings. In the more restricted sense, the soul is a more noble kind of life, a life of feeling, not the bare capacity for perception, but conscious feeling, with which attention is associated. The third and high- est kind of soul is the human, the anima rationalis, whose essence consists in the power of drawing gene- ral conclusions : ut ergo mens est anima rationahs, ita anima est vita sensitiva et vita est principium perceptivum. There is also a^perce^tio insensihilium, as I should be unable e. g. to perceive green, unless I could at the same time perceive yellow and blue, by a mixture of which colours it is made. A soul or an animal before its birth and after its death differs from those now living, not in its nature, but only in its place in the order of things and its degree of perfec- tion. Matter, or the outer garment, changes con- tinuously ; it is a natural mechanism, always in flux ; the organism is like the ship of Theseus, of which every part had been renewed ; the organic form is constantly renewed from the monads. Genii cannot exist without bodies, but have far more perfect ones, and perhaps have the power of changing their bodies. LEIBNIZ. 277 The same analogies run through the whole of nature, and it is easy to distinguish the iiner from the coarser elements, both of wliich follow the same kind of course. God alone is true substance, without material admixture, since he is always actus funis, not like matter, endowed with the power of suffering. All created substances are clothed with matter, thev have the property of the antitypy, which effects by natural means that one thing shall always be external to another and not penetrated by the other.' He speaks in the same way in his Com- mentatio de Anima Brutorum (Erdmann, p. 463) : 'No one will believe that there is any power of perception in a mill, a watch, or similar aitificial machines. However delicate the organic mechanism may be, we can still imagine it indefinitely en- larged, so that we could move about among its parts as we do in a mill, and still we should find everywhere parts only, not j^erception. Hence it follows certainly that it would be impossible to deduce either perception, acti^dty, or motion from mere mechanism or materia nuda. It is therefore necessary to assume something in addition to matter which shall serve to explain at once the inner ac- tivity or perception, and the outer activity or mo- tion. We call this principle substantial, vis pri- mitiva, Entelechy — in a word, soul. This active element must be conjoined with the passive to con- stitute substantia com,j)leta.' These passages show us the salieiit points of the Leibnizian theory. One admires the intellectual application expended in separating what is naturally united, so that throughout motion represents the fleeting, ephemeral, purely passive aspect of matter, while nevertheless a kind of consciousness is associated 278 MODERN PHILOSOPHY. with this, having nothing in common with the motion to which it corresponds, — but so perfectly regulated by the Divine watchmaker that the two continue in perfect correspondence throughout eternity. And human freedom is to be preserved at the same time, notwithstanding the regular course of the world on its mechanical side alone makes all divergence from the prescribed course impossible ! Schopenhauer, who is seldom quite just to Leibniz, speaks on this point with great severity^: ' The monstrous absurdity of his assumption was promptly pointed out by a contemporary, Bayle, who placed the necessary con- sequences in the clearest light.' But he adds : ' Yet the very absurdity of the hypothesis which a thought- ful mind was brought to accept, itself proves the magnitude, the intricacy, and the difficulty of the problem attempted, and how impossible it is to evade the difficulty by mere denial of its existence, as has been attempted in our days.' The premisses upon which Leibniz based his system were partly errors which have since his day become exploded, and partly truths which have not even yet received due recognition. I reckon among the former : — 1. The view established by Locke and Newton, with the concurrence of the Cartesians, that matter is something purely passive, which received its first impulse from the divine hand and continues to re- volve soul-lessly, retaining always the same quantum of motion as at first, and forming thus an invari- able mechanism explicable according to mathema- tical rules. 2. That mind is necessarily simple, and therefore cannot be a quality of extended matter. It is thus ^ Parerga, i. p. 8, LEIBNIZ. 279 exalted into a substance, a ' thing in itself/ and the old dualism is accordingly revived. 3. That because the individuality of things con- stitutes their essence, these are the Absolute, and the individuals characterised, — like the Platonic ideas, only in countless numbers, — must all continue to exist through eternity. It is true that continuity of individual coDsciousness is only attributed to man, both on account of the higher dignity whereby he enters into communion with the spirits who have intercourse with God, and because of the theological dogma of rewards and punishments. The truths are : — 1. The animation of all things; the recognition of an inner active principle co-operating or rather operating in everything which stirs or moves. 2. The emphasising of the individnal, as to which we feel and are taught by nature that it constitutes the true essence and differentia of all things, which are ever striving not only after subsistence, but after heightened and developed being. Two prevalent errors were herewith corrected : — {a) That of Spinoza, whose one substance swallowed up all particular existences and made them incom- prehensible. This is disproved, as Schopenhauer observes, by the unspeakable sufferings of the world and the ruthlessness of nature. (b) The error that universals, the elements of thought, can ever include or express what is indivi- dual. This error flourished down to our own day in the natural sciences, where it was assumed that all so-called natural forces were entities, things in them- selves, until the pregnant word was spoken by Ptobert Mayer, ' Forces are concretes.' Just as Leibniz had said : ' On a raison de refuter les Cartesiens quand 28o MODERN PHILOSOPHY. ils disent que Tame n'est autre cliose que la pensee, comme aussi quand ils disent que la matiere n'est autre chose que I'etendue. Car lame est un sujet, ou Concretum qui pense, et la matiere est un sujet etendu ou dou6 d'dtendue. L'Ecole a raison de distinguer les Concrets et les Absiraits, lorsqu'il s'agit d'exactitude ^' 3. The problem of sensible perception and the inner structure of the organism can only be solved by assuming universal and particular animation, ex- tending throughout the most minute material atoms, i. e, by the ^erce]j)tions infiniment ])etites of Leibniz. The so-called ' Philosophy of the Unconscious,' which has been proclaimed in our days with oracular preten- tiousness and a bombastic waste of crude phraseology, contains a slender kernel of truth, long ago discovered by Leibniz and clearly traced out into all its ramifying consequences. There are innumerable infinitely small perceptions of the body which do not attain the clearness of the intellectual principle which attends principally to the action of the chief organs of sense (the central monad of the rational human mind), and they remain therefore in the obscurity of an apparent unconsciousness. Leibniz correctly uses these dim per- ceptions to explain not only the vegetative functions of the body, but also the so-called mechanical or instinctive actions of men, i. e. those which have come from habit to be performed unconsciously. It is impossible to close our eyes to the presence of a perceptive element in such acts as walking, dancing, writing, or playing the piano, quite independent of the central consciousness, and indeed oulv liable to have its accuracy disturbed by having the attention of the latter directed towards it. This idea, which, ' Lettre a Remond de Montmort, p. 736, Erdmann. LEIBNIZ. 281 SO far as I am aware, has never received its due con- sideration, should be associated with the Darwinian doctrine of development as one of the most important principles of explanation. 4. This idea is closely connected with the thought of those continuous, gradual transitions which meet us evervwhere in nature, and laup-h at the ricid lines of demarcation which men lay down for their own guidance in dealing with isolated kinds or species. Leibniz's two favourite and fundamental axioms are Natura non facit saltus, and Non datur vacuum formarum. All changes are effected upon the infinitely Kttle, and a natural order in which all is organisation supplies material for an infinite multi- plicity of living beings. The same gradation obtains in the ease of minds as in the material world. There is a great difference between the feeling of animals and the reflection of human thought. 'II est raisonnable aussi qu'il y ait des substances capables de perception au-dessous de nous, comme il y en a au-dessus, et que^ notre ame, bien loin d'etre la derniere de toutes, se trouve dans un milieu dont on puisse descendre et monter ; autrement ce serait un defaut d'ordre ^.' ' I believe, at least,' he says elsewhere, ' that there is this analogy between minds and bodies, that as there is no vacuum in the material world, so the greatest possible multiplicity and variety exists amongst reasonable creatures. There is a complete series or gradation of beings from ourselves downwards, each variety only infinitesimally inferior to the last, iintil we reach the lowest of natural objects with the least possible measure of organisation ^' Especially interest- ing is the passage in a letter to his friend Hermann, ' Sur le Principe de Vie, Erdmann, p. 431. ^ Nouveaux Essais sur rEntendement Humnin, iii. 6. § 12. 282 MODERN PHILOSOPHY. in wliicli the subsequent discovery of zoophytes and polypi is forestalled : ' I should marvel less at the discovery of such animal plants, because I am con- vinced that such things must have an existence in creation. They will perhaps in time be discovered by naturahsts, when the infinite hosts of Uving creatures,' that escape ordinary observation by their minute size or their concealment in the recesses of earth and water, come to be investigated. Observa- tion is a thing of yesterday : how then can we deny a priori the existence of that which we have as yet had no opportunity of seeing 1 ' Another striking observation refers to the much debated question of essentia reales, which in fact includes the important joroblem of the nature of kinds and species, and by which throughout the middle ages philosophers were divided into the two camps of Nominalism and Realism : ' If the essentias reales are taken to be only substantial patterns, or types — such as a body and nothing else, an animal without other special qual- ities, a horse without individual characteristics — one might fairly condemn them as chimeras ^ And I believe that no one, even of the chief realists, has main- tained that there are as many purely generic sub- stances, as there are genera. But this does not prove that the essentige reales were mere signs- I have often pointed out that there are possibilities of resemblance. . . . One cannot form too vast an image of nature's liberality, it transcends all human thought, and a,ll conceivable possibilities find themselves realised upon her great theatre. There were formerly two axioms in philosophy: that of the Eealists made nature a spendthrift, that of the Nominalists a miser. The ' Tliat is to say, if reality is attributed to Universals, or to Platonic Ideas as such, as was done by the Eealists. LEIBNIZ. 283 former asserted Nature's horror of a vacuum, the latter that Nature did nothing in vain. Rightly understood hoth principles are true. Nature is lavish in her ejBFectSj and economical in the means or causes which produce them ^.' One asks oneself involuntarily how it was that Leibniz failed to formulate the Darwinian theory of development, when his sketch of the processes and action of nature was so entirely in harmony with the modern theory of descent, and one might even say based on more profound insight than our short- sighted estimate of ' living ' things, and their type, the primseval cell. He starts from the idea that all nature is animated and organised. The only ex- planation of his having stopped short where he did, seems to be his preoccupation (i) with the religious dog-ma that the world and all hvino- creatures were created, and (2) with the dogma of the Pre-established harmony, derived from the former, and the conviction of the impossibility of union between mind and matter. After this cursory abridgement of the Leibnizian philosophy we may proceed to consider his important suggestions in isolated fields of thought, and to begin with his contributions to I. llie theory of intellectual jjerceftiori. I. The first point to notice is his addendum to the Lockian 'Nihil est in intellectu quod non prius fuerit in sensu :' to which Leibniz adds the significant words nisi intelledus ijose. We might almost believe this to mean that Leibniz had undertaken to champion the cause of the 'innate ideas,' which Locke had ' jSTouveaux Essais, iii. 6. § 32. p. 320, Erdmann. 284 MODERN PHILOSOPHY. struggled so hard and so successfully to banish from jDhilosophy. The resumd which he gives, in a letter to Bierlino- of his criticism on Locke in the Nouveaux Essais would warrant such a view : ' Locke wanders far from the truth in the chief matter, and he has failed to discern the nature of the mind and of truth. If he had rightly weighed the difference between necessary truths and those which we reach to a certain extent by the way of induction, he would have seen that necessary truths can only be de- monstrated by principles implanted in the mind, the so-called innate ideas ; for the senses teach' truly ivliat happens, but not what happens necessarily. He has also omitted to consider that the idea of Being, of Substance, of Ideality, of the True and the Good must have been innate in our mind, be- cause it is itself innate, and comprehends all these things in itself.' In reality however Leibniz approaches steadily towards the Kantian doctrine of a jjriori elements in knowledge, as when he shows that mere experience cannot reveal necessary or universal truths, in which there is always something contributed from our own inner nature ^ : ' The senses, though necessary for all our actual knowledge, are not sufficient to have given the necessary or universal truths, since the senses give only instances, that is to say, particular or- individual truths. But the examples, which con- firm a general truth, do not suffice to establish the universal necessity of this same truth ; for it does not follow that what has happened, wiU always happen in the same way. . . . Whence it appears that necessary truths, such as we find in pure mathematics and especially in arithmetic and geo- ' Nouveaux Essaip, Avant-projsos, Erdmaun, p. 195. LEIBNIZ. 285 metry, must have principles of which the truth does not depend on the examples, nor, therefore, on the evidence of the senses, though without the senses no one would have begun to think of them. This distinction must not be neglected, as was Seen by Euclid, who demonstrates by reason what is sufficiently evident by experience and sensible images. Logic, morals, and metaphysics . . . are full of such truths, and their proof can only proceed from internal principles which are called innate. It is true that it is not to be supposed that these eternal laws of reason can be read in the soul, as in an open book, as the praetor's edict may be read in his album without trouble or research ; but it is sufficient that they can be discovered in us by dint of attention, of which the senses furnish occasions. The success of experiments serves to confirm the conclusions of reason, as in arithmetic a sum is proved, to avoid the risk of error in a long calculation.' In answ'er to the objection that particular pro- positions are accepted as indubitable truths by those who have no knowledge of more general maxims, he observes 1; 'It is true that we begin by perceiving particular truths, as we begin with the coarsest and most composite ideas ; but this does not prevent its being a fact, that the order of nature begins with what is simplest, and that the reason of the most particular truths depends upon the more general ones, of which they are only examples. And when any one desires to consider what is in us virtually, and prior to all ai^x^erception, he is right to begin with what is most simple. For general principles enter into our thoughts, of which they form the soul and the connection. They are 1 Nouveaux E&sais, Avant-propos, Erdmann, p. 211. 286 MODERN PHILOSOPHY. as necessary there as muscles and tendons are in walking, though we do not think of them. The mind rests constantly upon these principles, though it is not able easily to disentangle and represent them to itself distinctly and separately, because that requires close attention, and most people, being little accustomed to meditation, have none to give. Have not the Chinese articulated sounds as we have, and yet, having adopted another manner of writing, it has not yet occurred to them to make an alphabet of these sounds. Thus it is we possess many things without knowmg it.' The opponents of this view understand by innate truths those which would be instinctively approved, and these ought not to be confounded . . . ' But what is called the light of na- ture supposes distinct knowledge, and very often the consideration of the nature of things is nothing else than the knowledge of the nature of ovir mind and of those innate ideas which have not to be sought for without.' When challenged to produce a pro- position of which the ideas are innate, ' I should name the propositions of arithmetic and geometry, and there are no others to be found of necessary truths.' . . . But, if there are innate truths, must there not be innate thoughts ? Not at all : ' Car les' pensees sont des actions, et les connoissances ou les verites, en tant qu'elles sont en nous, quand m^me on n'y pense point, sont des habitudes ou des dis- positions ; et nous savons bien des choses auxquelles nous ne pensons gu^re \ ' ' In a certain sense it may be said that all arithmetic and geometry are innate, since we can realise their truths without any re- ference to experience, as Plato has shown in a Dialogue, when he introduces Sokrates leading a ^ Nouveaux Essais, Avant-propos, Erdmann, p. 212. LEIBNIZ. 287 child to abstruse truths by questions only, without ever teaching him anything. A man might therefore form these sciences in his library, and even with closed eyes, vpithout learning by sight or even by touch the truths he needed; though it is true that these ideas would never be considered at all, if we had not seen and touched things ^.' As to the eternal truths, it should be remembered that they are always at bottom liy])othetical, and only say, If the first is so, then the other is (necessarily) so also. These passages are sufficient to show that Leibniz did not await the sanction of experience to maintain those truths which the mind derived ' de son propre fonds,' or to point to a source of knowledge which indeed reqiiired the stimulus of the senses, but was essentially separate from them. His propositions are laid down apodicticaUy, as necessary, in the confidence that the human reason must originally have some- thing of its own : something which experience and the continual influence of the outer world through the senses may strengthen and develope, and which meanwhile grows into clearer consciousness of itself. Kant's great discovery of the a iwiori possessions of the human reason, which make experience possible, has the ground prepared for it here. As Kant introduced mathematics as the most powerful ally and the most brilliant confirmation of his doctrine, and assigned to it its proper place in the great classification of human knowledge, so Leibniz proved for the first time, what had been only guessed by the great thinkers of the past, from Pythagoras to Aristotle and from Descartes to Locke, viz. that the peculiar character of mathematical knowledge must furnish the key to the ultimate and most secret ^ Nouveaux Essais, Avant-propos, Erdmann, p. 208. 288 MODERN PHILOSOPHY. conditions of human reason, to its true nature and to its true, natural boundaries. 2. Leibniz laid down as tbe primary logical prin- ciples those of identity, of contradiction, and of the sufficient reason. ' In all demonstrations,' he says, ' I make use of two principles, of which one is that everything is false which involves a contradiction ; the second, that every truth, so far as it is not immediate or identical, must always have a sufficient reason, that is to say, the idea of the predicate must be expressly or im- plicitly contained in the idea of the subject ; and this holds good of demonstrations referring to things external as well as to internal ones, to contingent as well as necessary truths^.' The difference between necessary and contingent truths is very much the same as that between measur- able and immeasurable magnitudes. As we can reduce commensurable numbers to a common measvire, so a demonstration or reduction to identical propositions takes place in the case of necessary truths. In the case of surd numbers, on the other hand, the solution may be indefinitely approached, but the figures re- peat themselves in a circular series without end. In the same way, contingent truths require a pro- gressus in infinitum, an infinitesimal analysis which only God can complete. Hence they are only known with certainty and a priori by God. For the reason of the consequence is always to be found in its an- tecedent, which follows from another antecedent, and so in infinite succession. But this progressus in in- finitum is a reason in itself, as this must be found, ' At this rate all thought would be an analysis of composite conceptions, which would reach its goal when it had arrived at simple notions. Identical truths are excepted ; vide next note. LEIBNIZ. 289 outside the series, in God, the author of all things, on whom, much more than on their own causal con- nection, the earlier as well as the later must be assumed to depend. All truths therefore that do not admit of complete analysis, cannot be demon- strated by reasons of their own, but derive their ultimate reason and certainty from the divine spirit, and have not the character of necessity. All these I caU truths of fact ; and this is the real root of con- tingency, which has not, I believe, been pomted out before 1.' In this statement the human mind seems to be landing on unknown and undiscovered shores, and a distinction is perceived for the first time between the principles of thought, its inner logical form, and its contents, as originating from elsewhere. The new truths set forth are — a. All knowledge of fact has an empirical, con- tingent side, which can never be referred back to necessity. h. All certainty rests, in the last resort, upon the proposition of identity ; that is to say, reason is only fully satisfied when its operations end with a judg- ment of identity, and when the diff"erent elements under consideration are at last expressed in terms of each other, so that A = A^. c. All exclusion and difference rests, on the con- trary, on the principle of contradiction ; what is A, cannot at the same time be not-A. This propo- ' De Soientia Universali, p. 83, Erdmann. " Direct experience, such as that of our own existence, feeling, &o., and a 2>riori truths, rest on the proposition of identity, these because subject and predicate agree directly, those because subject and object are the same. Both kinds are therefore independent of demonstration. Nouveaux Essais, iv. cap. 9. § 2. VOL. L U 290 MODERN PHILOSOPHY. sition, according to Leibniz, lies at the foundation of all mathematical or necessary truths. d. The only principle of union between the thought which is on the one hand striving after unity and necessity, and on the other gathering in the mani- fold and diverse, is afforded by the principle of the sufficient reason, the clearest and most certain pos- session of the human mind. ' Ce principe est celui du besoin d'une raison suffisante pour qu'une chose existe, un evenement arrive, qu'une verite ait lieu. Est-ce un principe qui ait besoin de preuves ^ 1 ' The perception is dawning more and more clearly that, what has hitherto been sought in the world, such as unity and multiplicity, cause and effect, really lies at the root of the mental operations themselves, and must be sought out anatomically from the nature of the thinking mind and its primitive conditions. Philosophical investigation tends more and more to withdraw from what is objective and to take the Cartesian anchorage, the Cogito, for the starting-point of rational thought ; to see, in fact, more and more clearly that not Ontology, but Dianoiology is the thing required. This is true in regard to the pro- positions of identity and contradiction as well as to that of the sufficient reason, if we compare them with their doubles, the aeternse veritates, set up by Des- cartes himself: — 'Ex nihilo nihil fit.' ' Impossibile est idem esse et non esse.' These predicate heing, while identity and contra- diction refer to the reason itself and its elements, i.e. ideas. Three great thinkers repeat the same ontological proof of the existence of God, but we can ' Lettres entre Leibniz et Clarke, p. 778, Erdmaim. LEIBNIZ. 291 still see in their definitions of substance or Deity, as the first and last cause of all bemg, the progress that has been made from objective being to the source of thought. The reader will feel this by com- paring the following three propositions : — Descartes : ' Per substantiam nihil ahud intelligere possumus quam rem quae iia existit, ut nulla alia re indigeat ad existendum.' Spinoza : ' Per substantiam intelligo id quod in se est et per se concijpitur, hoc est, id cujus concepius non indiget conceptu alterius rei a quo formari debeat' (idea of being). Leibniz : 'II faut chercher la raison de I'existence du monde qui est I'assemblage entier des choses con- tingentes, et il faut la chercher dans la substance, qui porte la raison de son existence avec elle, et laquelle par consequent est necessaire et eternelle' (the reason of being). Descartes holds fast to the cause, Spinoza separates cause and reason, but allows them to be inter- changed ; Leibniz alone attains to the conception of the reason or the rational ground. Leibniz is still far from equalling the depth of the Kantian researches. He still considers the analytic method as the only one proper to human thought ; he does not realise that in every judgment, even the most ordinary one, synthesis and a priori certainty are involved as well. But the way on which he had entered led surely in the direction where the deepest mysteries of thought lay hid. The way was opened for the distinction between necessary and empirical knowledge ; for the first time that which is the mind's, was given to mind, in contradistinction to what belongs to the world or to reality. But the most important and most pregnant dis- u 2 292 MODERN PHILOSOPHY. tinction is that, contained in the principle of the sufficient reason, between reason and cause. We saw above in the philosophy of Spinoza, how much error and deception followed and could not but follow from the use of these principles as convertible. The prin- ciple of causality, upon which all earlier systems buUt blindly and unconditionally, — which is indeed the sole possession of human reason, and yet broke down whenever it was to be applied to the last problems, so that recourse had to be had to the causa sui, the causa prima, the Deus sive natura, — this princijole re- ceives now for the first time philosophic considera- tion, and becomes itself an object of investigation. The latter indeed was first entered on by Hume, whose doubt as to the reliability of the causal law made him act as the awakener of Kant. But the mere proclamation of this principle, as the primitive property of reason, was a progress not to be exagger- ated in the history of philosophic thought, of which the aim, since Descartes, has been to emancipate itself more and more from the external world, and to seek its sources within, where alone they are to be found, since what is given directly, i.e. in consciousness, must be more certain than what is given mediately through the other, viz. matter, or the external world. The self-deception of reason, in regarding objec- tive existence as the most certain and self-sufficing, takes effect here also. The causal relation pre- sents itself as a process accomplishing itself in the outer world and given thereby, so that at last the mind falls into the fundamental error of empiricism, in which Locke has shared, namely, that reason learns the fact of causality from the frequent re- petition of successive occurrences. It cannot indeed be ignored that reason itself plays an influential LEIBNIZ. 293 part in combining and uniting the causal links, since its most important task is to throw light upon the steps of practical conduct to be taken in ac- cordance with the conclusions regarding the future, based upon a knowledge of the causal series of the past. Thus its own proper name, ratio, ragione, raison, reason, is characteristic of the only case of its activity, i.e. the causal relation, which it applies to any fact or act before it. But it is long before it learns to distinguish correctly between cause and reason, and indeed, as we have seen, it continues still inclined to confound the two. It is only necessary to look closely at the analysis of the idea of cause, as bequeathed by antiquity, and held fast in the Middle Ages, to convince ourselves that the preponderance of the objective element made it impossible to conceive causality under the most important aspect of the rational ground (causa or principium cognoscendi). The classification into efficient causes and final causes (to whicli ' formal ' and ' material ' causes may be added) leaves the real ground of reason quite unconsidered, and assumes vsdth naive unconcern (i) that things act causally upon each other, (2) that man can change things in accordance with his intention. In the latter case, that of the final causes, a certain place is indeed allotted to reason, and scholasticism ap- proaches to a real insight : Causa finalis non movet secundum suum esse reale, sed secundum suum esse cognitum ; — but of the causa or the causae cognoscendi, there is never any mention. This most important point of view was only reached by Descartes, when, starting from the intelligent subject, the root and ground of the knowledge of this subject came to be investigated, and were shown to He necessarily within. 294 MODERN PHILOSOPHY. and not without it. The verification of our reason, as a special gift, necessarily presupposed in all know- ledge, led to a more attentive consideration of its operations, and this again could not but result in bringing into view what was everywhere silently as- sumed, viz. the principle of the sufficient reason. The Leibnizian principle of the sufficient reason thus for the first time, albeit somewhat tentatively, relegates the principle of causahty to the realm of the knowing subject, or to reason. The old pro- position, Everything in the world must have a cause, -will read now. In virtue of the principle of the suffi- cient reason no fact will be admitted as true or really existing, no judgment as correct, luiless a sufficient reason is forthcoming why it is thus and not other- wise \ 'Leibniz,' says Schopenhauer-, 'proclaims this pro- position with great solemnity in many passages of his works ; and gives himself airs of great importance, as if it was he who had invented it ; and yet he has nothing more to say about it than that each and all things must have a sufficient reason — which the world knew already.' This sneer, however, does not hit the mark, for we have not to do with the invention of a rational principle, but with the discovery of its true place and importance. That man thinks, and is con- scious of himself, was known long before Descartes; that everything is perceived in space and time was known long before Kant; and similarly the principle of the sufficient reason has always been made use of in thought, just as we use our bones and muscles in walking. But that it was one of the fundamental "to" ' Monadologie, § 32. ^ Die vierfache Wurzel des Satzes vom zureichenden Grunde, p. 16. LEIBNIZ. 29s and indeed the most important of rational principles, since tlie knowledge that one ball forces away another was first derived from it — this was not known before Leibniz, and his great merit is to have put the fact in its proper light. ' Causahty is in us,' this is the gist of Leibniz's thought. Hume will add, ' Causality is in us alone, and ought not to be transferred to the outer world.' ' Causality is in us and is of value and significance only in so far as it is applied to experience and reality,' will be the conclusion of Kant. 3. According to Leibniz there are three kinds of knowledge : (i) intuitive, which has a iwiori or mnate truths for its object ; (2) demonstrative, which is reached by the principle of the sufiicient reason 1; (3) sensible, which he characterises as an obscure or confused kind of knowledge. For this latter heresy Leibniz is again severely reprimanded by Schopenhauer 2. 'AH abstract knowledge,' he says, 'flows from intuition, and all its value and significance lies only in its relation to intuitive per- ception. For this reason the natural man always attaches much more value to what is known by direct intuition than to abstract ideas, or what is merely thought ; he prefers empirical to logical knowledge. But those who live more among words than deeds, who look more into books and papers than the real world, are of the opposite mind, and in their worst degeneracy turn into pedants and slaves of the letter. ' 'La Eaison consistant dans renohainement des Veritas a droit de lier encore celles que Fexperience lui a fournies pour en tirer des conclusions mixtes : mais la liaison pure et nue, distinguee de Fexperience, n'a a faire qa'k des v6rit6s ind^pendantes des sens.' Discours de la conformite de la foi avec la raison, Erdmann, 479. ' Schopenhauer, "Welt als Wille und Vorstellung, i. p. loi. 296 MODERN PHILOSOPHY. This is the only explanation of how Leibniz, together with Wolf, and all their successors, could go so far astray as, like Duns Scotus, to pronounce intuitive knowledge only a confused form of abstract know- ledge. To the honour of Spinoza it must be said, that his juster mind, on the contrary, declared all general ideas to have arisen by the confusion of what was intuitively known.' (Eth. ii. Prop. 40. Schol. i.) This criticism too is unjust, and the passage cited from Spinoza refers only to the first and original way in which general ideas were formed, as appears clearly from the scholium immediately following, where he says, in complete agreement with Leibniz, ' Ex his omnibus, clare apparet nos multa percipere et no- tiones universales formare primo ex singularibus nobis 2)er senstis mutilate, confuse et sine orcline ad intel- lectum reprassentatis.' When Leibniz represents sensible knowledge as confused, he is placing it in opposition to that which Spinoza, in the last-named scholium, calls ' scientia intuitiva, quod cognoscendi genus procedit ab adgequata idea essentia formalis quorundam Dei attributorvim ad adsequatam cogni- tionem essentise rerum.' The relation of sensible perceptions to the true nature of the things which excite them is conceived in exactly the same way by Leibniz. ' Sensible ideas are dependent on single forms and motions, and express these exactly, al- though we are unable to recognise the particular elements in the confusion of the infinite number and minute details of mechanical actions. But if we could really behold all the inner constitiition of the body (i. e. according to Locke its qualitates prima- rise), we should have a clear knowledge of its pro- perties, which might then be traced back to it by intelligible reasons ; even though we might never be LEIBNIZ. 297 in a position actually to perceive them with our senses. A rapidly revolving wheel with long teeth presents a kind of transparency to the view at its periphery; such is confused sensible knowledge, while intellectual intuition, the clear conception of the thing itself, easily distinguishes the teeth \' Schopenhauer's criticism is so far justified that Leibniz does not expressly distinguish between ra- tional and sensible knowledge, but regards both as generically ahke, the latter being only a less perfect variety of the former. But notwithstanding all this, an important truth was beginning to dawn at this point upon the mind of Leibniz, namely, that our sensible perceptions, considered objectively, are no- thing but unconscious mmieration. This idea, like the Lockian primary qualities, is only a natural conse- quence of the doctrines alike of Atoms and of Monads, hut Leibniz seems, as was not unnatural, to have first been led to it by his reflections on the na- ture of music, which consists in rhythmic intervals, or harmonic successions. He describes listenina' to O music as an ' exercitium arithmeticum nescientis se numerare animi,' and says: 'Musicdelights us, although its beauty consists only in regularity of numbers and in a numeration (of which we are not conscious) of the vibrations of resonant bodies, following each other at regular intervals. The pleasure of sight from pro- portion is of the same nature, and that of the remain- ing senses no doubt will be reducible to something similar, though we cannot so easily explain them '^.' If the pleasure which we receive by the senses, the Agreeable and the Beautiful, only rests upon the un- conscious numbers of regular rhythm, it necessarily ' Nouveaux Essais, p. 358, Erdmann. ^ Principes de la Nature et de la Grraoe, p. 718, Erdmann. 298 MODEEN PHILOSOPHY. follows tliat sensations in general can be nothing but a similar unconscious numeration, a view in perfect harmony with that above developed, respecting the infinitely little and therefore unperceived mechanical motions. ' For the nature of the mind consists of perceptions, and as we perceive the body as a whole, but do not perceive the infinitely little parts of which it consists, so the infinitely slight perceptions which are caused by the latter do not attain to the clearness of consciousness ^.' ' When we perceive colours or odours, it is only a perception of infinitely small forms and motions, so that our mind cannot possibly per- ceive the same distinctly, and so does not observe that its perception is made up of infinitely small percep- tions; just as in a mixture of yellow and blue powder, the separate particles are not seen, but the whole appears to us as green, so that we believe we see a new thing (ens) ^.' Natural science, it is well known, has given brilliant confirmation to Leibniz's conjec- ture, so far as colour is concerned, since the latter has been explained by vibrations of difierent duration : but as to the two more deeply-rooted senses, taste and smell, the empirical proof has still to be given, and undoubtedly will be given in due time. The theory of sensible perceptions as unconscious numeration, which was at least first imagined and suggested by Leibniz, is of very great metaphysical significance. Some ultimate and decisive questions naturally attach themselves to it. If the perceptions of sense are the original material of all further know- ledge, is this numeration the last point at which we can arrive 1 Is analytic empiricism therefore, which still consciously grasps the units in their vanishing ^ Epistola ad Bierling, p. 678, Erclmann. ^ Meditat. de Coguit. verit. et ideis, p. 81, Erdmann, LEIBNIZ. 299 minuteness, the last and only goal of the enquiring human mind 1 Hume will answer in the affirmative. Kant, on the other hand, will penetrate much further at this very point, and show that, in this very primary and original form of knowledge, in number, or perceptions in time, synthesis and the a priori form of time is presupposed, and by it alone experience rendered possible. Thus the ultimate boundary, the ne plus ultra of all knowledge, will be fixed. II. Physics. I . The concejptioii of Force. It is indisputably one of the chief merits of Leibniz to have elucidated this idea and to have laid it down as the fundamental conception for the study of nature. If the student of nature at the present day, in aU his experiments and inferences, starts from and returns to this idea, if in all the varying phenomena and manifold magic of the outer world, his endeavour is always to grasp the one natural force and to bring it into subjection to thought and law, this mode of viewing things traces its origin to Leibniz. He founded the dynamic conception of nature, which has since continued to prevail. Descartes, as we have seen, placed the nature of matter in bare extension, so that formally it became identified with space, and the most curious contra- dictions ensued. Locke, seeing these contradictions, introduced the idea of solidity as the primary quahty of matter, to which all other primary qualities were attached. Leibniz, on the other hand, put forward the one correct conception of force, maintaining that it is only in action that beuig makes itself felt, and reveals its existence : quod non agit, non existit. 300 MODERN PHILOSOPHY. ' Notliing is purely passive — id quod passivum est, nunquam solum reperitur aut per se subsistit ; — any- thing that was so would be unable even to receive or to retain an impulse of motion from without^' 'We only perceive motion, and so fax everything happens only in accordance with mechanical laws, but the cause of the motion, the fons mechmiismi, i.e. the active Force, must always be presupposed, and this is not to be explained mechanically, but metaphysically ^.' ' I was delighted with the fine methods of mathematicians for explaining everything mechanically, and I justly despised the methods of those who explained all things by forms and faculties, from which nothing was to be learnt. But as soon as I sought to understand the principles of mechanics themselves, I saw at once that mere extended magnitude would not suffice to enable me to comprehend the laws of nature shown by ex- perience, but that the conception of Force must be invoked, which is very intelligible, although it belongs to the region of metaphysics ^.' ' The most important, hitherto little known or little understood truths are associated with the idea of substance, the true nature of which can only be conceived by starting from the idea of force. This I propose to set forth in a sepa- rate work on the science of dynamics. For there is a great difference between active force and the so-called potentia activa or facultas of scholasticism ; the latter of which is a mere possibility of acting, if an external influence is brought to bear. But the vis activa is ' Epistola ad Hoffmannum, p. i6i, Erdmann. '■' ' Mea semper fuit seiitentia omnia in corporibus fieri mechanioe, etsi non semper distincte explicare possimus singulos mechanismos : ipsa vero prinoipia mechanismi generalia ex altiore fonte profluere.' lb. p. i6i. ^ Systfeme Nouveau de la Nature, p. 124, Erdmann. LEIBNIZ. 301 an Entelechy, intermediate between the mere facultas agendi and the actus itself, and needs no further in- citement to action than the removal of hindrances in the way. It is thus with the stone hanging by a strained rope, or a bent bow. The ultimate source of all motion is the original force lying in all bodies, which may be limited or restricted in various ways by the conflict or collision of other bodies. This force lies in all substances, and a certain action always arises from it. No bodily substance ever ceases to act, and this has not been sufficiently recognised by those who have supposed its nature to consist of extension and impenetrability only, and have imagined that it was possible for a body to be ever entirely at rest. Thus no created substance can ever receive the vis agendi from another, but only conditions and limita- tions of its own action 1.' It was through Leibniz that the conception of matter first became clear and serviceable for men of science, after its chief quality had been compared and assimilated with what was best known and most familiar to man, namely his own bodily force, which is the measure of everything else. This step must have shed a degree of light in the days of Leibniz comparable to that thrown in our own days by the discovery that force can only be measured by its effect, and the consequent estimate of natural forces by the worlt done. It is interesting, and helps to explain the develop- ment of the most important conceptions in natural science, to compare the utterances of Descartes and Leibniz on the subject of matter and its nature. We shall see from this more clearly how fluctuating and indefinite the idea continues, so that Descartes at ^ De Primas Philosophiae Emendatione, p. 122, Erdmann. 302 MODEEN PHILOSOPHY. times speaks the language of Leibniz, while Leibniz continues to hamper himself with the Cartesian definition. Descartes : ' Qui autem dicunt, actionem omnem ab agente auferri posse, recte dicunt, si per actionem motum solum intelligant, non autem si omnem vim sub nomine actionis velint compre- hendere, ut longitudo, latitude, profunditas et vis recipiendi omnes figuras et motus a materia sive quan- titate toUi non possunt.' (Epistolse, i. 86.) Leibniz: ' Principium activum non tribuitur a me materiae nudae sive primse, quae mere jjassiva est, et in sola antityj^ia et extensions consistit.' (Epist. ad Wagnerum, Erd. 466.) Here, where we can observe the intermingling of the conceptions of force and extension, where Descartes speaks of the poiver. of extension, while Leibniz calls resistance, its antitypy, something purely j^asswe, we can see too the difficulty of the birth-struggles of clear ideas, and how everywhere the new is entangled with the old, how it developes with slow but steady growth, and how something of the earlier impression is always carried on into the new. For even Leibniz himself, who first yielded to the conviction that the nature of matter must be sought in force alone, still retained some remnants of the former view. He still separated in thought the traditional conception of matter as the subject, the support of force, as that in which force appears, and thus he ascribed a real — or at least a phenomenal — existence to a mere thing of the mind, materia nuda, or prima. Hence it came to pass that he was obliged to attribute to it certain qualities which he derived from the dominant opinions ; in other words, his clear insight was obscured, and much which should have been deduced from the nature of force alone, as extension, impenetrability, resist- LEIBNIZ. 303 ance, still seemed to him an original property of matter, wMcli in itself was purely passive. Hence contradictory expressions and assertions, such as : ' Matter is that which resists penetration ; the first matter is therefore purely passive ^ ; ' the vis inertige which is defined as ' vis passiva resisiendi et impene- trabihtatem et aliquid amplius . involvens ^,' and the like. The fact, however, remains that the idea of Force, which is so exclusively and so effectively made use of in modern physics, because by it alone the two qualities of mutability (the transitional) and per- manence can be reconciled without contradiction, had its first origin in the mind of the great Leibniz. 2. The conservation of force. With the growing prominence of the idea; of force, and the increasing tendency to deduce all changes reveaHng themselves in matter from it, as a phasnomenon bene fundatum, the discovery of the great law of the indestructibility of energy was coming nearer and nearer. The primi- tive conviction which had always instinctively assumed the presence of something permanent, that law which was first formulated in the materialistic doctrine of Demokritos and Epikuros (ex nihilo nihil fit and nihil fit ad nihilum), was now advancing rapidly towards the clear and definite expression which in our days it has begun to reach, as the last cloudy remnants of the idea of matter were absorbed in the concep- tion of force, or, more accurately, of motion. The definition above quoted (p. 300), according to which force itself is inseparable from the idea of matter, so that motion is by no means always to be looked on as somethmg communicated, tended to ' Epist. ad Bierling, p. 678, Erdmann. ^ De Ipsa Natura, ib. p. 157. 304 MODERN PHILOSOPHY. accelerate the conclusion according to which (appa- rent) rest is only a restriction of the innate force within the body, which only awaits the removal of these obstacles in order to manifest itself in life. Leibniz knew very well that this law must exist a j)riori ; that it could not possibly proceed from experience, a view which seems not as yet to have dawned upon the majority of our men of science, who lose themselves in such phrases as that Natural science h&s, proved the law of the conservation of force ! As if anything could be proved by experience, which has to be taken for granted before the sUghtest experience can be acquired ! The universal mechanism of nature is the firm and indispensable base of all natural knowledge, and what is mechanism but the trans- mission of force ? Leibniz says, with great point : ' Spinoza (I am not afraid of quoting him when he says what is true) in a letter to Oldenburg makes a similar remark about a work of Sir Eobert Boyle, who, to tell the truth, delays too long over a number of fine experiments without drawing from them any other conclusion than that which he might have taken as his premiss, namely, that everything in na- ture is accomphshed mechanically, a principle which can only be proved by reason, and never by experi- ments, however numerous they may be ^' I can only briefly mention the controversy as to the measure of force, which was so long connected with the names of Descartes and Leibniz, dividing the learned world into two camps, and to which Kant him- self contributed in one of his youthful works ^. Des- cartes said that the measure of force is the quantity of ■■ Nouveaux Essais, iv. I2 ^ ( 1747 ^ Gedanken von der waliren Schatzung der lebendigen Krafte, LEIBNIZ. 305 motion, mv, i.e. mass multiplied by velocity. Leibniz said forces were proportioned as the square of the velocities mv"-. Descartes also maintained that the motion or quantum of movement in the universe always remains the same ; while Leibniz asserted, on the contrary, that it was not the quantity of motion but that of vis viva which remained the same. Descartes took the imparted motion as the unit of measurement, and this agrees with his funda- mental view, according to which matter is something self-su.bsisting (extended) to which the determined motion is communicated from without by God^. Leibniz, on the contrary, placed the cause of motion in matter itself, of which the true property is just this force motrice^. He therefore took as the sole standard the most imiversal manifestation of force, the one which underHes all natural science, gravity, and the free fall of bodies. ' According to my view,' he says, ' forces stand in the proportion of the heights from which the heavy bodies must fall to attain their velocity. But as the force in the universe remains the same and is sufficient to ascend to a corresponding height or produce any other similar effect, it follows thence that the amount of living force in the universe is maintained unimpaired ^.' ^ Epistol. ii. 25, 'Primo statui esse in tota materia creata certain quantitatem motus quae neque augeatur neque minuatur unquam ; atque ita, qimm corpus unum movet aliud, tantundem motus sui ipsius decedere quantum in aliud transfert.' Motion for Descartes is not a real quality, only a mode. ^ 'Je ne connais point ces masses vaines, inutiles et dans I'inaction dont on parle. II y a de V action fartout, et je I'etablis plus que la philosophie refue : parceque je crois qu'il n'y a point de corps sans mouvement, ni de substance sans effort.' Eclaircissement du Nouvtau Systfeme, Erdmann, 132. ^ Lettre a M. Bayle, Erdmann, p. 193. VOL. I. X 306 MODERN PHILOSOPHY. I will here only observe that in modern science the Leibnizian standard -f' has been accepted as the base of the principle of the conservation of force in the formula, ' Tlie sum of the vis viva and static force in the world remains the same always.' Leibniz has expressed this principle more or less clearly in many passages of his works : — ' The idea of Force is very different from that of motion, the latter of which is more relative. One must measure the force by the quantity of its effects [in modern English, tvor¥\. There is an absolute, a directing, and a resjoective force. All maintain them- selves in the universe, or in any machine which does not communicate with others ; the two latter together compose the first, absolute force. But the same quantity of motion is not maintained, otherwise the perpetuum mobile would be found, and the effect would be greater than its caused' ' Descartes beheved that the same quantity of motion was preserved in bodies. It has been shown that he was in error in this ; but I have j^roved that it is true that the same amount of moving force is preserved, which is what he confounded with the quantity of motion I' A passage in the correspondence between Leibniz and Clarke is very interesting for its bearing on this subject, as we gather from it, (i) the difficulty which this idea of the conservation of force met with at its birth, since even so clear-headed a man as Clarke could not disabuse himself of the common prejudice as to the genesis of force ; (2) how Leibniz, first of all mortals, caught a glimpse of the great truth which ' Lettre k M. Arnauld, Erdmann, p. io8. ^ Eclaircitsement du Nouveau Systfeme, p. 132, Erdmann.. LEIBNIZ. 307 ranks among the chief discoveries of Eobert Mayer, viz. the conversion of molecular into collective motion, and conversely. Clarke writes^ : ' I have shown that the active force in the world naturally suffers constant diminution. It is obvious that this is not a mistake, it is a consequence of the inertness of matter. For this inertness not only causes the diminution of velocity in proportion as the quantity of matter increases (which indeed is no diminution of the quantity of motion), but it also causes solid bodies which are quite hard and \m-elastic to lose all their inotion and active force, if they encotmter an equal and opposing force; another cause is therefore needed to impart new motion to them ' (i. e. reparation by means of the great Artificer). Leibniz replies : ' I had maintained that the vis viva in this vmi verse continues the same. It is objected that two inelastic bodies if they come into colhsion will lose some or all of their force. I say. No. It is true that the wholes lose it in relation to their collective movements, but the parts receive this as they are moved internally by the shock. The forces are not destroyed, but distributed amongst the particles. The effect is the same as when one changes large coins into small ^.' The application of these ideas to heat is found in the Nouveaux Essais^ : 'With regard to the opera- tion of most natural substances, analogy is the great rule of probability. What cannot be verified can only appear probable in so far as it agrees more or less with established truths. Since . the violent friction of two bodies produces heat and even fire, ' Erdmann, p. 785. ^ lb. p. 775- ^ iv. 16. § 12. X 2 3o8 MODERN PHILOSOPHY. since refractions of transparent bodies cause colours to appear, we judge that fire consists in a violent agitation of imperceptible particles \' &c. I have shown above that Descartes was penetrated with the sense of the unchangeableness and invari- ability of the mechanical principle in the world of matter ; he expresses the great truth that the soul is not in a position to produce or to destroy the least atom of motion. He sought some way of giving a foundation to the universal and positive certainty that by means of and in consequence of our feeling, thoiight, and will, we can move our limbs in ac- cordance with our conscious purpose : and he found the right way, which makes freedom possible within the bounds of an invariable mechanism ; for he saw that given forces, combined by superior intelh- gence, would be able to make other forces subject to them, by giving them the desired and serviceable direction. This is the true solution of the famous antinomy, which Kant himself maintained to be '■ Intimations of this idea, whicli was destined to effect a revolu- tion in the whole theory of nature, are to be met with in antiquity also ; tlie whole doctrine of Herakleitos appears to us to-day as a kind of anticipatory divination of the mechanical theory of heat. Plato is clearly reproducing Herakleitean ideas in the following remarkable passage of the Thesetetos (ix. 153) : — ' Sok. For fire and warmth, which are supposed to be the parent and nurse of all things, are born of friction, which is a kind of motion ; — is not that the origin of fire ? 'Thecet. Yes. ' Sok. And the race of animals is generated the same way 1 ' Thecet. Certainly.' It is also especially interesting that Sokrates-Plato interprets the Homeric golden chain by which all the gods failed to move Zeus, as the sun by whose motion in the heavenly space all life on earth and heaven was preserved, while its arrest would bring the destruction of all things. LEIBNIZ. 309 soluble, viz. how liberty can subsist in the midst of universal natural necessity. It is true this so- lution did not agree with Descartes' assumption of two substances, having nothing in common with each other. And it agreed equally little with the Monism of Spinoza, with the una substantia, for it is only possible with individual beings which act upon each other, i.e. with relative forces ; it is in- applicable to the All. Spinoza accordingly, consist- ently with his own assumptions, assumes everywhere the strictest necessity, while Descartes gave expres- sion to the truth which forced itself upon his con- sciousness, though in doing so he became unfaithful to his own principles; he had recourse to the spiritus animales, an infinitely subtle material which (not indeed without divine assistance) is moved direct from the soul, i. e. is dii'eded by its own proper motion, and causes the motion of our members in ac- cordance with the will, i. e. gives them their direction. This inconsistency did not escape Leibniz's pene- tration, and it was easy to hun to vanquish Descartes with his own weapons. He says in a letter to Ber- nouilli (1696)1: 'Not only the same absolute force, but also the same directing force (vis directiva) or quantity of direction (quantitas directionis ad easdem partes, or quantitas progressus) is preserved in the universe; and this is not measured as the square, but as the simple product of the mass and the velocity. For when two bodies moving from opposite directions meet together, the Cartesian law only says of the quantity of motion that the two motive forces must be added together, whereas it is only from the difference between the two that the quantity of progress or direction can be ascertained.' 1 Erdmann, p. 108. 3IO MODERN PHILOSOPHY. In another passage he says ^ : ' Descartes was per- plexed about the bodily changes which follow upon modifications of the soul, because these do not obey his law. He hit accordingly upon a very ingenious invention, and said, one must distinguish between the motion and the direction. The soul is unable to alter the motive force in any way, but it can change the determination or direction of the vital spirits, and it is thus that our arbitrary movements are produced. It is true he was careful not to explain how the soul could change the course of the body, since this is quite as incomprehensible as its im- parting motion to the body, since he does not, hke me, refer to the pre-established harmony as an ex- planation. But there is another important natural law, which I have discovered and of which Descartes was not aware, namely, that not only is the same quantity of vis viva always preserved, but also the same quantity of direction, in w^hatever dii'ection we may turn. That is to say, if one draws a straight line and assumes such and so many bodies moving in that direction, we shaU find that the quantity of progress on all the lines parallel to this straight line will always remain the same ; so that one can calcu- late the quantum of progress by deducting the force of the bodies tending in the opposite direction from that of the bodies moving ui the direction of the line ^- This law, which is as beautiful and universal ^ Eclaircissement du Nouveau Systfeme, p. 132, Ei-dmann. " This permanence of the direction in the universe follows from the principle 'Actio par est reactioni,' which holds good for the Cartesian measure of force (mv) of each movement beginning in the universe. Newton expresses the principle as follows : ' Aotioui contrariam semper et asqualem esse reactionem sive corporum duorum actiones in se mutuo semper sequales esse et in partes contrarias dirigi.' (Princ. Phil. Nat. Math. Axiomata, lex iii.) LEIBNIZ. 3 1 I as the other, is equally incapable of being violated, and this is the case in my system only, which establishes the conservation of force and of direction.' If one contemplates the vast multiplicity of motions, the play of vital forces on our own small planet, if one sees on the one hand how winds and waves seem in their motions subject to no law but chance, while, on the other, in the animal world, movements seem to originate by unrestrained arbitrary choice, and both determine themselves in every possible direction, — we shall cease to wonder at the error of which Epikuros furnishes the most striking example in antiquity, the error of supposing that the direction of motion is determined without cause, by mere arbitrary will, and so escapes the sequence of strict mechanical causation. If this were conceivable, men might fly without wings, or birds without a resisting medium, i. e. without air. According to Epikuros, the atoms fall with equal velocity in parallel direc- tions, in absolutely vacant space. In this he has the advantage of Demokritos, whose atoms have different velocities because of their different weights. Whence then is the multij^licity, the vortex of com- binations and separations 1 Epikuros helps himself out of the difiiculty — as modern Darwinism with the ceU hypothesis' — with an apparently small and insig- nificant petitio principii. ' Once, at some undeter- mined time, certain atoms found themselves induced to take a trifling lateral motion ^ !' Lucretius indeed, like Descartes, refers to the arbitrary movements of men and other animals. But Leibniz's keen gaze discerned all this to be so muck contraband in the strictly knit system of physical causation. 'Everything in the human body,' he writes, 'down ^ Lucretius, de Ker. Nat. ii. 251, 293. 312 MODEKN PHILOSOPHY. to the least detail of its phenomena, happens just as if the false doctrine of Epikuros and Hobbes, which as- sumes the soul to be a material being, were true ; that is, as if man were only a body, an automaton. The view of Descartes concerning animals (that they are only machines) has been transferred to men and attempts made to show that the latter, with all their reason, are only the passive playthings of images and mo- tions. And the endeavour to refute this error only served to prepare a triumph for it, for upon this side it is unanswerable. The Cartesians were almost as unlucky as Epikuros with the declension of atoms, of which Cicero makes such fun, when they tried to make out that though the soul was unable to impart motion to the body, it was able to give it direction. In fact it can do neither the one nor the other, and the materialists need not return to the subject, for there is nothing external to man capable of refuting their doctrine \' According to Leibniz there was but one issue from these difficulties and imavoidable contradictions be- tween the direct consciousness and the a priori cer- tainty of mathematical and physical axioms ; and this was the assumption of his pre-established harmony, which on that very ground seemed to acquire more irrefragable certainty in his eyes. He beheved him- self to have been the first to solve the eternal op- position between matter and mind. He failed to see that he himself too had given his system a dogmatic base in his divine Creator, that he had made the elephant stand vipon the tortoise, while he had no answer to the objection already referred to, addressed to him by Clarke in his last letter (171 6, imme- diately before Leibniz' s death) : ' On dit qu'il n'est pas ^ E^plique aux Reflexions de Bayle, Erdmann, p. 185. LEIBNIZ. 313 possible de concevoir comment una substance imma- terielle agit sur la matiere. Mais Dieu n'est-il pas une substance immatdrielle et n'agit-il pas sur la matiere M' III. Metajpliysics. In answer to his Lockian opponent, who pro- nounces metaphysics to be mere empty chaffering with words, which experimental knowledge is destined to supersede, Leibniz declares ' that we are now only at the beginning of the foundation of true meta- physics ; and we find already many truths founded in reason and confirmed by experience which refer to substances in general. I hope myself to have contributed something to the general knowledge of the soul and of spirits. Such a metaphysic was demanded too by Aristotle ; it is the science which he calls XriTovfievri, the Sought, which must stand to the theoretical sciences in the same relation as the science of happiness does to those arts of which it makes use, and as the arcliitect to the masons. There- fore it is, said Aristotle, that the other sciences must depend on metaphysics as the most general, and ought to borrow from her the principles which she has de- monstrated ^.' Leibniz was thus clearly aware of the nature and function of metaphysics ; if he failed to penetrate to its source, it was because he looked for this upon the opposite side, starting, not like Kant, from the sub- ject, but, like Aristotle and the Schoolmen, from Being, or Substance. ' Metaphysica agit turn de ente, tum de entis affectionibiis ; ut autem corporis natur- alis affectiones non sunt corpora, ita entis affectiones > ErdmanD, p. 787. ^ Nouveaux Essais, Erdmann, p. 372. 314 MODBKN PHILOSOPHY. non sunt entia ^Z The close bearing of the mathe- matical sciences on metaphysics, due to the former being occupied with the most general relations was clearly established by him. Scholasticism had main- tained that number was only an interruption of continuity, and therefore did not apply to immaterial substances. This Leibniz denied, for number is also, as it were, an immaterial figure, formed by the com- bination of the most various beings. God, angels, man, motion are four things. As number is there- fore something universal, it certainly belongs to meta]3hysics. We may thus call metaphysics the doctrine of all that is common to all kinds of Beings. This was approximately the standpoint of Scho- lasticism. Leibniz, like Descartes and Spinoza, was of the opinion that all knowledge should be proved mathematically, and so reduced to mathematical cer- tainty. He blames those who measure heaven and earth by this method and do not apply it to the more important knowledge of God, the Soul and the Good. ' Sunt qui mathematicum vigorem extra ipsas scientias quas vulgo mathematicas appellamus, locum habere non putant. Sed illi ignorant, idem esse mathematice scribere quod in forma, ut logici vo- cant, ratiocinari I' Yet Leibniz seems to have under- stood by this a higher kind of mathematics, to which arithmetic and geometry stand in the relation of parts to a whole, a method of calculation which was to deal with the analysis of ideas and from which he hoped great things : ' J'ai insinue ailleurs qu'il y a un calcul plus important que ceux de I'arithmetique et de la geometrie et qui depend de I'analyse des ^ De Arte Combinatoria, Erdmami, p. 8. * De Vera Methodo Pliilosophise et Tlieologiae, Erdmann, p. no. LEIBNIZ. 315 iddes. Ce serait une caracteristique universelle dont la formation me paralt une des plus importantes choses qu'on pourrait entreprendre\' In regard to metaphysical conceptions, in the 'Epi- stola ad Thomasium'(i669) Leibniz still reckoned four kinds of Entities, namely, Mens, Spatium, Materia, and Motus. Space is with him mathematical exist- ence or mere extension, while matter has the further qualities of resistance, occupation of space, and im- penetrability 2. But in his later writings he had reached a much greater depth of metaphysical insight. Thus he says in the ' Eeplique aux Eeflexions de M. Bayle ^ ' ' E6plique aux Eeflexions de Bayle, p. 191, Erdmann. Leibniz's idea was to introduce a new art, which was to reduce everything to exact mathematical terms and characters — ad expressionem cogita- tionum per characteres (De Scientia Universali seu Calculo philo- sophico, p. 83, Erdmann) — as the only method for putting an end to the controversies of the schools and the barren outcry of the sects. All paralogisms would then be shown to be mere errors of calcula- tion, and the disputes of philosophers would be ended by their sitting down to a table and saying ; Calculemus. It is true this art, like geometry, is only available in so far as it starts fi-om data, but these will he provided for it by all the sciences, medicine, jurisprudence, politics, &c. He promises that, with the help of this novum organum, the range of human knowledge will be as far increased as the range of vision has been by the telescope and microscope. This 'scientia universalis' was thus to accomijlish for knowledge in general what geometry and mechanics do for physics. This great plan of a Characteristica universalis, which was associated with the idea of a universal language, was a favourite dream of Leibniz, but it remained only a project. At the present day, when we know the dependence of thought on language and the impossibility of re- ducing human thoughts by mere analysis to mathematical precision, we can see the impossibility of its execution. The attempt made by Bishop Wilkins (1668) to found a universal language failed, as all others of a similar nature since made have done also. ^ p. 53, Erdmann. ^ lb. p. 189. 3l6 MODERN PHILOSOPHY. (1702) : 'I admit that time, space, motion and con- tinuity in general, as assumed by mathematicians, are only ideal entities, that is to say, they express possi- bilities, as numbers do. Hobbes has even defined space as a phantasma existentis. But, to speak more precisely, extension is the order of possible co- existences, as time is the order of possible changes, which, however, are so definitely connected, that these orders refer not only to real but also to pos- sible things, such as may take their place, just as number stands in a relation of absolute indifference to the res nuonerata. And although we never meet in nature with such absolutely identical changes as mathematics assume in dealing with motion, or with absolutely regular figures, such as geometry supposes ; yet there will be found nothing in nature in the least contrary to the law of continuity or any other exact rule of mathematics ; indeed it is only by these rules that all things can become generally intelligible. . . . Although mathematical considerations are only ideal, their application is to things actual, which are per- manently subject to these rules.' In the Nouveaux Essais ^ he gives the same de- finition of space : ' It is a relation, an order, not only of existing things, but of those which possibly might exist. But its truth and reality are founded on God, like all eternal truths.' Similarly he says of time ^, in reference to Locke's observation that the succession of ideas gives us the conception of time : ' A succes- sion of perceptions rouses in us the idea of duration, but does not create it. Our perceptions never have a sufficiently constant and regular succession to correspond to that of time, which is a uniform and ^ ii. 13. § 17. p. 240, Erdmann. ^ Tb. ii. 14. § 16. p. 241, Erdmann. LEIBNIZ. 317 simple continuum, like a straight line. The change in our perception gives occasion to think of time, and we measure it by uniform changes ; but if there were nothing uniform in nature, time would not therefore cease to be determined, just as space would still be determined though there were no fixed or motionless bodies. It is because we know the rules of multiform motions that we can refer these to uniform, intelli- gible movements, and so predict what wiU follow by taking these different movements together ^' A characteristic instance of the superior insight of Leib- niz as compared with the standpoint of Lockian empiricism is furnished by the objection of Phila- lethes (Locke) : ' It is very strange that, as men visibly measure time by the motion of the celestial bodies, tliey should nevertheless define time as the measm-e of motion 2' and its refutation. We see clearly that Leibniz had entered upon the ' Newton's definitions approach very closely to those of Leibniz, and point also towards the coming light of Kantian truth. ' Tern- pus ahsolutum, verum et mathematicum in se et natura sua absque relatione ad externum quodvis sequabiliter fluit alioque nomine dicitur Duratio. Relativum, apparens et vulgare est sensibilis et externa qusevis Durationis per motum mensura (seu accurata seu inaequabilis) qua vulgus vice veri temporis utitur, ut Hora, Dies, Mensis, Annus . . . Aocelerari et retardari possunt motus omnes, sed fluxus temporis absoluti mutari nequit.' Philos. Nat. Prino. Math. Defin. viii. Schol. He says similarly of space : ' Absolute space, in itself and without regard to anything external, remains eternally the same and immoveable. Relative space is any moveable dimension or measure of absolute space determined by our senses by the position of bodies.' Nothing need be said of the attack subsequently made upon Newton by Leibniz because the former maintained Space to be the sensorium of the Deity, for Newton either used the word metaphorically to signify the Omnipresence of God or attached no very definite idea to it. 2 Nouveaux Essais, ii. 14. § 22, p. 242, Erdmann. 3l8 MODERN PHILOSOPHY. true metaphysical path at the end of which the great discovery of the ideality of space and time was to be reached. A letter to des Bosses (1709) shows still more clearly the severance of the ideal space from reality. ' Space, like time, is a certain order (i. e. the order of coexistence) which embraces not only the real but also the possible. It is therefore indeter- minate, like every continuum, the parts of which are thought arbitrarily, not in reality, like the parts of unity or fractions. If there were other subdivisions of real things in the world, there would be other monads, other masses, but space would remain the same. For space is a continuum, but an ideal one. The mass is something divided, an actual number, an aggregate of infinite units. But in real things the units exist before the grouping, in ideal ones on the contrary the whole is before the parts. The neglect of this consideration has always led into an endless labyrinth ^' ' The parts of time and sj)ace,' said Leibniz in his correspondence with Clarke ^, ' taken in themselves are ideal things, they are therefore perfectly similar, like two abstract units. But this is not the case with two concrete units, two real periods of time, two real portions of occupied space, — these are actual.' ' I have shown that space is nothing but the order of the existence of things, which are considered as existing together. Thus the fiction of a finite, mate- rial universe, moving through infinite space cannot be admitted. It is unreasonable and useless, for apart from the fact that there is no I'eal space outside the universe, such an activity would be entirely pur- poseless, it would work without having anything to do, agendo nihil agere. These are the fancies of ^ p. 461, Erdmann. ^ p. 766, Erdraann. LEIBNIZ. 3 1 9 philosophers with imperfect conceptions, who make space an absolute reality.' Leibniz had thus clearly grasped the ideality of space and time ; but instead of remaining faithful to this principle and relegating the ideal to its true dwelling-place, in the feehng and thinking subject, he transferred these two forms or categories to the world or substance unconditionally presupposed by himself, and explained space as the order of coexist- ing things and time as the order of changes in things. But here the question had first to be asked, how such an idea as order in general came into existence, whether it is an original possession of human thought — for it is certainly only an abstract or intellectual idea — or whether the forms of space and time are not rather much the earlier and more primitive and serving rather to make the other conception possible. The same kind of vicious circle, or rather petitio prin- cipii, meets us here as in the pseudo-definitions of post-Kantian philosophers, who explain space as the measure of contiguous and time as the measure of suc- cessive things, — and then imagine themselves to have told us something, — as if measiire, contiguity, and suc- cession were possible without the primary forms of space and time. Order can only exist for a mind. The principle of the order of things can therefore be sought or found in the thinking mind alone. If Leibniz had fami- liarised himself with this thought, instead of assuming an order of things imposed from without, he would have remained within the true field of inquiry and would perhaps have forestalled Kant. He would then have enquired what primary possession unites the mind through the senses with a real or outer world, and thence first deduced the order of things in the mind. 320 MODERN PHILOSOPHY. Clarke was right in objecting that there was nothing abovit quantity in the idea of order. In his last letter he observes ^ : ' The author says now that space is not an order or place, but an order of places, [so that space again is taken for granted]. That does not prevent tlie same objection from holding good, that the order of places is no quantity. And when he says, time is only the order of successive things, and at the same time maintains that it is the quantity of duration existing between the single successive things, this is obviously contradictory.' For the rest, in his later works Leibniz clearly shows his insight into the nature of metaphysics and the distinction beween them and mathematics and their respective methods. Thus he says ^ : ' To ap- ply the geometric method to metaphysical objects is praiseworthy, but the attempt has met with httle success. Descartes, in spite of his powerful in- tellect, has never accomplished less than when he made use of it in his answers to objectors. For one gets off more easily in mathematics, because numbers, figures, and calculations are a protec- tion against the errors lurking in words ; but m metaphysics, where this aid is wanting, the strict- ness of the reasoning and the exact definition of ideas should supply the want ; but here is to be found neither of these requisites.' ' According to the usual expression, mathematical principles are those which we meet with in pure mathematics, such as numbers, arithmetic, geometry. But metaphysical principles refer to general ideas, such as cause and effect. Especially that great principle belongs here, ' Erdmann, p. 785. ^ Remarques sur la Sixi^me Lettre Philosopliique, p. 684, Erd- LEIBNIZ. 321 that nothing happens without a sufficient reason for its happening thus and not otherwise \' Hume wiJl attach his metaphysical investigations to this highest possession of human thought or reason, and from this point of departure estabhsh his own Skepsis, thus connecting Leibniz and Kant. If now we review the achievements of the Leib- nizian philosophy and its place in the development of philosophic thought, we shall find in it a peculiar agreement with the philosophy of Locke, and at the same time a direct opposition to the same. The agreement lies in the insistence upon the individual. Locke started from the individual thinking being, and asked. How does this being attain knowledge 1 His theme is 'An enquiry into the nature of under- standing.' Nature means, like its Greek equivalents, Physis or Genesis, the becoming, and the becoming of knowledge was to enlighten Locke as to its being. His answer ran : All knowledge is derived from sen- sation. Now sensation always presents things mani- fold, which the human understanding has to arrange in classes. It does so by means of general ideas, which constitute the great distinction of human, as compared with all other knowledge. But instead of examining more closely into this contrast of conceptions and per- ceptions, Locke contented himself with having pointed it out : dazzled by the discovery that ah. the mate- rial of knowledge is derived from without by means of sensibility, he conceived all knowledge to be as it were a mechanical product, and, hke his great pre- decessor in Empiricism, Bacon, he turned the reflec- tive faculty into an automatic mirror, which, without ^ R6ponse k Mr. Clarke, p. 751, Erdmann. vol. I. Y 322 MODERN PHILOSOPHY. further inner principles, just Herat et resonat at the stimulus of reality. Metaphysical principles lie out- side the scope of human knowledge. We learn by experience to know time, space, and infinity. If any one asks "What is space 1 the true answer is : I do not know. Leibniz too starts from the individual being. While Locke raises sensation or the passive re- ceptive element into a universal principle from which all subsequent knowledge is to be derived, Leibniz on the contrary places the active element in the foreground everywhere. Like Descartes, he is penetrated with the great truth that thought, con- sciousness, will are We ourselves ; all the rest is only indirect knowledge. Instead of the one sub- stantia cogitans of Descartes, he accordingly as- sumed an infinity of small substances, to which this property of thought essentially belonged. The in- ternal or representative faculty thus constitutes the proper nature of all substances. Kant points out that Leibniz attributed everything exclusively to the conceptions of the understanding and Locke to sen- sation, whereas these are the two sources of knowledge which have to unite, before we can know anjrthing at all. He shows that the fundamental error of the Leibnizian doctrine was (i) his treating the concep- tions of the understanding as the true matter of thought, and sensible intuitions as a similar, only less perfect and confused, kind of knowledge, and (2) his regarding phenomena as things in themselves, which could be comprehended by means of these conceptions. The important remarks on this subject in Kant's CritiJc der reinen Vermmft ^ are as follows : ^ On tlie Ampliiboly of reflective concepts. Transl. vol. ii. p. 2 3 1 . LEIBNIZ. 323 'We only know substances in space through the forces which are active in space, by either drawing others near to it (attraction) or by preventing others from penetrating into it (repulsion and impenetra- bility). Other properties constituting the concept of a siibstance appearing in space, and which we call matter, are vinknown to us. As an object of the pure understanding, on the contrary, every substance must have internal determinations and forces bearing on the internal reality. But what other internal acci- dents can I think, except those which my own internal sense presents to me, namely, something which is either itself tliougM, or something analogous to it 1 Hence Leibniz represented all substances, as he con- ceived them as noumena, even the component parts of matter (after having in thought removed from them everything implying external relation, and there- fore composition also), as simple subjects endowed with powers of representation, in one word, as monads! ' Leibniz therefore first assumed things (monads), and within them an internal power of representation, in order afterwards to found thereon their external relation, and the community of their states, that is, their representations. In this way space and time were possible only, the former through the relation of substances, the latter through the connection of their determinations among themselves, as causes and effects. And so it would be indeed, if the pure understanding could be applied immediately to ob- jects, and if space and time were determinations of things by themselves. But if they are sensuous intuitions only, in which we determine all objects merely as phenomena, then it follows that the form of intuition (as a subjective quality of sensibility) comes before all matter (sensations), that space Y 2 324 MODERN PHILOSOPHY. and time therefore come before all phenomena, and before all data of experience, and render in fact aU experience possible. As an intellectual philosopher Leibniz could not endure that this form should come before things and determine their possibility, a cri- ticism quite just when he assumed that we see things as they are '.' ' He compared all things with each other by means of concepts only, and naturally found no other differ- ences but those by which the understanding distin- guishes its pure concepts from each other. ... In one word, Leibniz intelledualised phenomena, just as Locke, according to his system of Noogony (if I may use such an expression), sensualised all concepts of the understanding, that is, represented them as nothing but empirical, though abstract, reflective concepts. Instead of regarding the understanding and sensibi- lity as two totally distinct sources of representations, which however can supply objectively valid judg- ments of things only in conjunction with each other, each of these great men recognised but one of tliem, which in their opinion applied immediately to things by themselves, while the other did nothing but to produce either disorder or order in the representations of the former ^.' In these passages the relation of Kant to all preceding philosophy, as well as to these special pre- decessors, is clearly manifested : the keynote is the elimination of the idea of substance, to which these like all the rest return, after attempted flights, as to the only sure and certain foothold. This contrast alone shows the eagle strength of wing with which Kant's genius was to bear him into the pure heights of idealism, where gravity no longer chains his flight. ^ Loc. cit. p. 232. ' Loc. cit. p. 235. LEIBNIZ. 325 To sum up once more the connection between modern philosophy and these its two great repre- sentatives : — I. The cogito of Descartes determines (i) the sub- jective (individual), (2) the idealistic starting-point. The material world presents itself as substantia ex- tensa, as one uniform system, while the substantia cogitans is a complete enigma. IT. Materialism and idealism build on the founda- tion of one or other substance. Subjectivity and indi- viduality threaten to disappear (the spiritual through the atoms, the material by means of ideas) ; they will be completely absorbed III. By means of the una substantia. Monism itself. IV. After the idea of unity, a fruit of the Car- tesian ideahsm, has been sufficiently invigorated by the revision and development of the idea of sub- stance, the rights of the manifold assert themselves again, and individualism revives in a new and more perfect form. JjQr-KTf. V Leibniz Founds it upon the renewed Starts from the multiplicity cogito, enquires after the origin of substances to which he at- of ideas, and finds it in the tributes thought. As they are multiplicity of sense - impres- things in themselves and inde- sions. The understanding is only structible, it is the task of reason orderly sensation. to distinguish them. Sensation is only imperfect understanding. The reader will see from the above contrasts how the standpoints are changed in the course of deve- lopment, how irreconcilable opposites melt into one, and how after the first introduction of idealism by Descartes, its tone and character were borrowed by the most realistic of systems. For there can be no 326 MODERN PHILOSOPHY. doubt that Locke, the realist and empiricist, here combines Platonic and Herakleitean ideas, the eternal flux and change of sense-impressions with the dura- tion and permanence of ideas : and yet he is all the while a genuine modern, i.e. idealistic philosopher, and assigns that which Plato and Heraldeitos be- lieved themselves to see in the objective world to its true birthplace, the feeling and thinking subject. Leibniz, on the contrary, the pure ideahst, for whom the material world and space were but phenomena, incapable of any interaction with spiritual substances, combines, as he himself says, Demokritos and Aris- totle, by spiritualizing the atoms of the former into monads and retaining the formse substantiales of the latter, which come into existence by means of the monads and their organic power, for every organism has a central monad. Locke accordingly represents the share of sensa- tion in the genesis of ideas, Leibniz that of the intellectual element, which is present in even the most trifling and meagre perception. This opposi- tion proceeds from the difierence of the starting- points, and a higher unity had to be discovered to reconcile the two. Locke represents everything as coming into the understanding from without, Leibniz represents everything as developing from within. Both are obviously right ; both see the same object, but from opposite sides. The errors and narrowness of great men reveal themselves most clearly in their successors and in the schools which found a system on their principles. Locke's empiricism led De Condillac to the sensation transformee, to the axiom, ]^enser c'est sentir, and the extreme consequences of French materialism, which may be passed by in silence, notwithstanding recent LEIBNIZ. 327 ephemeral attempts to exalt them as the ripest fruits of modern wisdom, Non ragioniam' di lor, ma guarda e passa. The school of Wolff, which for a long time pos- sessed universal popularity on account of its in- telligibility, its self-confidence, and its apparent con- clusiveness, was thoroughly realistic in character. It was the philosophy of enlightenment, and this was its title to recognition and victory. Eeason and its process is the highest type of judgment concerning truth. It has been pointed out often enough that Wolff's philosophy degenerated into a dry and empty formalism, that he was the founder of a new scholasti- cism, dogmatising unintelligently over the profound- est metaphysical ideas of Leibniz, and illustrating the most trivial matters at length with the whole methodical apparatus of philosophy. The idea of Leibniz, that the reason develops everything out of itself, is established as a principle ; then the true possession of the reason, ideas, are taken as the starting-point, and then, by the help of the principle of the sufficient reason, (which is to correspond to the principle of identity), and the principle of contra- diction, everything is developed by analysis out of these ideas. There is no question as to the origin or authority of these ideas ; they are there, and every- thing that was in them already is evolved from them at leisure. Things in themselves and ideas are treated as exactly equal, for nihilum est cui nulla resjwndet notio, and aliquid est cui aliqua res^pondet notio, are Wolffs ontological starting-points. As however, in spite of the distinction between a priori and a post- eriori truths, which he inherited from Leibniz, the important distinction between empirical and a priori knowledge was not made, his whole philosophy ran 328 MODEEN PHILOSOPHY. to seed with empty tautologies, circular reasoning, and unfounded dogmatism. The latter fell into three chief divisions, rational psychology, rational cosmo- logy, and rational theology, the great objects of which — God, the world, the soul and its ideas, — were to be demonstrated thence. The dogmatic confidence with which the victorious reason proclaimed its oracles in syllogisms, arguments, axioms, and defi- nitions received a violent shock from the scepti- cism of Hume, which supplied the arms with which Kant penetrated into the citadel that had so long been held impregnable, and destroyed the whole in- genious fabric by showing that it consisted entirely of the self-created illusions of reason, travelling beyond her proper boundaries. THE SKEPSIS. HUME (1711—1776). ' Nasce per quelle, a guisa di rampoUo, Appife del vero il dubbio ; ed h natura Ch' al sommo pinge noi di collo in coUo.' Dante. David Hume was one of the most earnest, pro- found, and honest thinkers who have ever occupied themselves with the great problem of the universe and the human mind. The ' honest doubt,' which gave so much scandal to his contemporaries, was more helpful and productive than thousands of fohos filled with the dogmatism that had passed for ages as the highest wisdom, and with the fullest and most confident accounts of God, the world, and the human soul, which reason, operating upon its own manu- factured notions, could construct. When it occurred to reason to inqiiire into the grounds for these notions and to test its own assumptions, the dog- matic tower of Babel fell to pieces, Hke a house of cards. It has often been observed that Hume's scepticism instigated Kant's Critique of Pure Eeason. Kant himself says ^ : 'I confess frankly, it was the warning voice of David Hume that first, years ago, roused me from dogmatic slumbers, and gave a new direction ^ Prolegomena, Vorwort. 330 MODERN PHILOSOPHY. to my investigations in the field of speculative philo- sophy. I was far from yielding assent to his con- clusions, which came from his not having conceived his task as a whole, but having addressed himself to a single portion, as to which no satisfactory result could be reached without reference to the whole. When one starts from a thought that has been es- tablished, but not carried out to all its consequences, by another, one may reasonably hope by continued meditation to carry it a step further than the man to whose genius we owe the first spark of such light.' Hume's attack was directed against the central point of reason, its true and sole possession — the idea of causation. This idea makes science pos- sible, which, without it, would be a mere aggregate of observations and curious mquiries. 'Even true opinions,' says Plato, ' are of httle value when they are not based upon reasons which hold them together in the mind.' And Aristotle says : ' The empiricists know that something is, but they do not know the wherefore ; theorists on the contrary know the why and the cause ^.' And Schopenhauer calls Why ? ' the mother of all the sciences.' Schopenhauer says of Hume : ' Before this serious thinker no one had doubted that the j)rinciple of the sufficient reason, in other words, the law of caus- ality, stood first and foremost in earth and heaven. For it was an " eternal truth," subsisting independ- ently, superior to the gods or destiny : everything else, the understanding which apprehends the prin- ciple, as well as the world at large and whatsoever there may be which is the cause of the world, such as atoms, motion, a creator, or the like, exists only Oi fiiv efinfipoi TO on fiiv 'ia-acri, fiioVi 8' ovk 'iaaiTiv' oi Se rep^fiToi to StOTi Ka\ TTjv alriav yvapi^ovcri. Metapll. i. I. HUME. 331 in conformity with and in virtue of this. Hume was the first to whom it occurred to ask whence this law of causahty derived its authority, and to demand its credentials ^.' Let us now consider whether the time had come to formulate this question and to disturb reason in its citadel by calling its securest possession in ques- tion, and threatening to declare all its knowledge self-delusive. Locke, in tracing all knowledge to experience, had deduced the cavisal relation from the same root; he laid down that the effect of the will upon the members of the body and the resistance of bodies to our pressure were the origin of the idea of cause. All knowledge, including this most important, is therefore purely empirical. Leibniz, on the other hand, accorded its due place in the system of human knowledge to the idea of cause, or rather to the principle of the sufficient reason. He indicated it as one of the most important duties of metaphysics to investigate and explain the primary ideas from which human thought takes its start, and notably this idea of cause. Besides this, Leibniz had established the important distinction between necessary and accidental truths, and had referred the latter, which include all actual matters of fact, to an endless causal series, while the former may be reduced to simple, and in the last resort, to identical propositions. It was this opposition between empirical or con- tingent, and necessary or identical truths, that the penetrating glance of Hume decided to be irre- concilable, whence he concluded that causation and experience were incompatible, and that our as- ^ Vierfaclie Wurzel des Satzes vom zureichenden Grunde, p. 20. 332 MODEBN PHILOSOPHY. sumption of things happening necessarily — which still meant their happening because of something else — rested accordingly on self-deception. Here too it is really the eternal contrast between the manifoldness of the world and the craving of our reason after unity which encounters us as we get to the root of the difficulty. Necessity only reveals itself to our thought by the perception of identity, and this therefore, as formal and logical certainty, under- lies all the most elementary truths. But whence comes the assumption that this formal logical equi- valence corresponds to the world of fact and will find its appHcation there 1 If sensible and rational know- ledge is nothing more than a highly improved method of analysis, then there remains at last nothing but the infinite multiplicity of individual existences, whose co-existence and co-operation can only be explained by a miracle, i.e. the monads and the pre-established harmony. If, on the other hand, reason assumes, with vain self-sufl&ciency, that its notions correspond exactly to the nature of existing things, it will ima- gine itself able to explain the latter by merely ana- lysing its own conceptions ; and it must soon become apparent that any such reasoning revolves in a never- ending circle. Empiricism can never lead to unity and necessity, for experience is only of the manifold, whether within ourselves or in the external world. No artifices of reason can convince us that different things are one, i. e. that the different is the same. And nothing less than this is claimed for the idea of cause ; it requires us to assume that because A is, therefore B 'must be too. And this is more than rational thought can ever know or admit concerning the self-subsisting things of the outer world. HTJME. 333 On the other hand, a priori truths furnish no road ' to the multiplicity and diversity of real things ; for all these truths are at bottom merely identical pro- positions ; and what store of knowledge can be derived from identical propositions \ The idea of cause and effect involves fundamentally incompatible assvimptions regarding our reason, by applying the formal logical unity to the multiplicity of sense perceptions, and by attributing universality and necessity to things which are by nature single, and accidental or contingent. Hume was not, as Schopenhauer says, in the pas- sage quoted above, the first to contest the vahdity of the causal law in the objective world. The sceptics of antiquity had recognised the importance of the question and pointed out some of the in- consistencies involved, and had deduced thence the impossibility of any certain knowledge grounded on necessity. In the old world naturally this was done mainly in the form of a])erfus, while in modern philosophy, which had found the true starting-point of all knowledge in the thinking subject, this on- slaught of Hume's dealt a home thrust. Among the earlier sceptics ^nesidemus denied the possibility of making the sequence of one thiqg from another intelligible to the reason, saying that nothing is the cause of anything else, and they who seek after causes delude themselves i. The later sceptics gave five reasons which should determine suspense of judgment (eiroxv)- I. cnro Sia(j)(ovias, the uncertainty of words; there is no criterium either in sense or thought by which ■* Mrjbev jj-h firjSevbs o'ltcov (Ivai, rjirarrjaBm de tovs ahiokoyovvTas ^d^Kcov. Phot. Bibl. 212; cf. also Sext. Empir. Hyp. Pyrrhon. i. 180. 334 MODERN PHILOSOPHY. we can be assured that the same thoughts are at- tached by different persons to the same word. 2. airo Ti?? eiV airetpov eKTTTMO-eojf, — the prOgTCSSUS in infinitum, — the fact that every cause has a cause, and this another and yet another ad infinitum. 3. airb Tov irpog ti, the relativity of all things ; we know in what relations a thing stands towards other things, we cannot know what it is in itself TTOOy Tr]V (pUlTlV. 4. e| v-TToOecreu}?, because dogmatists always start from something that has been taken for granted. 5. The argument in a circle, when the conclu- sion sought for is presupposed in the arguments leading to it ^, as, for instance, when one says, man has language because he has reason, while reason is impossible without language. Other reasons against causality preserved for us by Sextus Empiricus (Adv. Mathem. ix. 207) are interesting, as they agree with those brought forward by Hume, thus giving one more proof of the im- possibility of finding an}^ thought that has not been at least partially and accidentally forestalled. ' Cause,' say the sceptics, ' is a relation. The cause of the cut- ting of meat is a knife ; the knife and the meat are real, but the cause is not real, only a Trpo? n, a thing of the mind.' There are three conceivable causal relations : — ' I. That contemporary things should cause each other (to afj.a ov TOV afia ovtois). This is perfectly unthuikable, for if two things exist at the same time, one cannot be thought of as originating {jewri- TiKov) the other. ' 2. That the earlier should catise the latter (to -n-po- repov TOV vcrrepov ttoiijtikw). As long as A stands alone, ^ Sext. Emp. Pyrrh. Hyp. i. 164. HUME. 335 it is not a cause, for the effect is wanting to complete tlie relation ; as soon as B has appeared, A is no longer there, and the cause is absent. ' 3. That the later should be the cause of the earher is inconceivable both on the ground just alleged, and according to every other principle of sane judgment. ' Moreover a true cause, a causa agens, properly so called, must always produce the effect out of itself ; it does not require the co-operation of matter or something passive {jo -Kaa-xov). The dogmatist who assumes cause to be a relation, a Trpo^ n, ac- cording to which the cause may be known by the nature of the passive effect and the effect by the nature of the cause, commits the error of using two words to designate the same thing {imia ewoia Svolv S' dco/xa-ftiv Tev^erai) ^ ; for how can there be a doing without a suffering, or a suffering without a doing 1 ' From these acute and, in fact, reasonable argu- ments, we see two things, viz. the incomplete, naive objectivism of antiquity, which saw and sought for everything in the external world, in the unquestioned reality of things ; and secondly, the scepticism which naturally sprang from the incompleteness of this standpoint, and so led to a presentiment of the ideality of causation, while it was supposed to be relegated to the regions of nothingness. Such con- siderations can only serve to illustrate the real great- ness of Descartes and his work. ^ The ancients used the illustration of a chariot and its driver, the latter of whom at the same time moves and is moved by the former. And though at the present day we need not be perjjlexed by this difficulty, there remain other similar ones undisposed of, e. g. in a moving mass what is to be regarded as active or impart- ing motion, and what as passive or moved 1 336 MODERN PHILOSOPHY. The significance and force of Hume's scepticism could only be appreciated by an intellectual equal, while others raised the cry of heresy and appealed to ' common sense.' It is amusing to note how most of his adversaries imagined themselves to have de- molished Hume, when they had shown how in one chapter (Essay vii) he denies the necessity of the causal sequence, and hence inferred the uncertainty of knowledge, while in the following chapter human freedom is called in question, because everything happens by way of cause and effect. They forgot that a similar mconsistency had lurked for centuries in human thought itself, which assumed at the same time the strict necessity of all cognition, and the unlimited freedom of all action, so that it was a real service to reverse the point of view, as it was ob- viously fair to do, and so rouse the slumbering reason from its lethargy. Kant says with great force and justice ^ : ' Since the attempts of Locke and Leibniz, or indeed since the origin of metaphysics, as far back as we can trace its history, there has been no incident so decisive of the possible fate of the whole science as the onslaught of David Hume. He brought no new light to this branch of knowledge, but he kindled a spark whence light might have been derived, if it had fallen upon fitting tinder.' ' Hume took his start principally from a single but important metaphysical conception, namely that of the connection of cause and effect (together with the consequent conception of force and action) ; and he summoned the reason, which professed to be its author, to give an answer for herself and declare by ' Prolegomena, Vorwort. HUME. 337 what right she supposes that anything of such a nature can exist, that whenever it exists, something else necessarily exists forthwith ; for this is what the conception of cause involves. He proved conclusively that it was impossible for the reason to construct a priori such a connection which involves necessity ; for it is impossible to see how because one thing is, another thing should necessarily also be, or how the conception of such a connection should have been introduced a priori. He concluded from this that the reason was entirely deceived as to this idea, was in error in regarding it as its own offspring, seeiag that it was really a bastard child born of the imagination and experience. From this alliance sprang certain ideas which were brought under the law of association, and the subjective neces- sity arising thence, i.e. habit, is treated as the ob- served objective necessity. From this he inferred that the reason possessed no power of thinking such connections, even in a general form, because its con- ceptions would then be pure fictions, and that all its vainly subsisting a priori knowledge was nothing but common experience under a false brand, which is much the same as saying there neither is nor can be such a thing as metaphysic ^.' ^ ' Hume himself, however, gave the name of metaphysic to this destructive philosophy, and attached a great value to it. ' Meta- physic and morals,' he says, ' are the most important branches of knowledge ; mathematics and natural philosophy are not half so valuable.' "With all his aouteness, Hume in this looked only at the positive help to be derived from moderating the exaggerated claims of speculative reason, so as to do away with the endless, intolerant disputes which perplex the human race ; he lost sight of the, posi- tive injury arising when the most important truths are taken out of the hand of the reason, which has nothing left to propose to the will as the highest goal of its efforts.' Kant's note. VOL. I. Z 338 MODERN PHILOSOPHY. 'However premature and incorrect his conclusion may have been, it was at least based upon investiga- tions which deserved the co-operation of the ablest ininds of his generation in the attempt to solve th^ problem in the sense he indicated, an attempt which miTst have resulted in a complete intellectual reform. ' But unfortunately the malevolent fate which seems to watch over metaphysics had decreed that no one should be able to understand him. One cannot ob- serve without a certain degree of pain how all his op- ponents — Eeid, Oswald, Beattie, and even Priestley, — all without exception miss the point of his con- tention by taking for granted the very thing which he is calling in question, at the same time that they demonstrate with great violence and hardihood points which it had never occurred to him to doubt, and so misunderstood his invitation to improvement that everythmg remained just as it was before. The ques- tion was not whether the conception of cause was just, serviceable, and indispensable in relation to all na- tural sciences, for this had never been disputed by Hume ; but whether it could be conceived a ^priori by the reason, and thus possessed an internal truth independent of experience which would make it admit of more extended application, not limited to matters of experience. This was the point as to which Hume demanded information. The question was only as to the origin of the conception, not as to its practical in- dispensableness ; if only the former point were cleared up, the conditions and limitations of its validity would follow of themselves. 'His opponents, to deal satisfactorily with their task, would have had to penetrate deeply into the nature of reason, in so far as it is occupied with HUME. 339 pure thought, and this they found inconvenient ; it was easier to assume a defiant bearing and simply refer the matter to ' common sense.' Sound, or as it is sometimes called, plain common sense, is in fact a very rare and precious gift of heaven. But its possession must be proved by deeds, by deliberation and reasonableness in thought and speech, not by appealing to it as an oracle, when the speaker has nothing else sensible to allege. ' To appeal to human common sense just when — and not before — knowledge and insight begin to fail, is one of the most uigenious inventions of our age, and one which enables any shaUow babbler to hold his own against thinkers of depth and thorough- ness. So long, however, as any fragment of insight remains, this expedient need not be resorted to ; and looked at in the right light, such an appeal is simply a reference to the judgment of the masses, a kind of sanction which makes philosophers blush, while popular witlings boast of it triumphantly. I should have thought that the claims of Hume to a healthy common sense were as strong as those of Beattie, while he certainly possessed, what the other as cer- tainly did not, the critical reason by which common sense is held in check, and not allowed to lose itself in speculations or to seek to decide upon questions involving principles which it is unable to verify; for in this way only can it continue to deserve the name it claims. Chisel and maUet may suffice for a job of car- pentry, but the engraver requires a needle for his art. Thus both common sense and speculative intelligence are useful in their way, the former when we have to do with judgments with a durect practical application, the latter when general conclusions have to be de- duced from abstract conceptions, as, for instance, in Z 2 340 MODERN PHILOSOPHY. metaphysics, where the self-styled (sometimes by antiphrasis) common sense has no jurisdiction at all; Notwithstanding this crushing attack upon the opponents of Hume, there still seem to be some writers who do not understand what is the issue involved. This appears from the irrelevant remarks with which Mr. Lewes, in his Problems of Life and Mind (ii. pp. 408-412), aims at controverting Hume, which should serve as a warning to aU those who oc- cupy themselves with philosophy, without having first penetrated into the spirit of Kant's writings, and having learnt from them what must be accepted as the foundation and starting-point of all true philo- sophy in the future. To neglect Kant is the same thing as to amuse oneself after Lavoisier with expe- riments in alchemy, or after Bopp with the ancient etymological trifling based on casual resemblances of sound. I will now proceed to reproduce in brief outline the simple and yet convincing course of Hume's ar- guments. ' Surely,' he says, ' if there be any relation among objects, which it imports to us to know perfectly, it is that of cause and effect. On this are founded all our reasonings concerning matter of fact or ex- istence. By means of it alone we attain any assur- ance concerning objects which are removed from the present testimony of our memory and senses. The only immediate utility of all sciences is to teach us how to control and regulate future events by their causes. Our thoughts and enquiries are therefore, every moment, employed about this relation ; yet so imperfect are the ideas which we form concerning it, that it is impossible to give any just definition of HUME. 341 cause except what is drawn from sometliing ex- traneous and foreign to it^' Most writers on the subject either ' employ un- intelligible terms or such as are synonymous to the term which they endeavour to define. Thus, if a cause be defined that whicli produces anything, it is easy to observe, that producing is synonymous to causing. In like manner, if a cause be defined that ly which anything exists, this is hable to the same objection. For what is meant by these words hy which ? Had it been said that a cause is that after which anything constantly exists, we should have understood the terms. For . . . this constancy forms the very essence of necessity, nor have we any other idea of it 2.' We get here at the root of the whole enquiry. Our inner consciousness tells us that we are not satisfied with mere succession in time as an account of the idea of cause. The question accordingly arises whether in the above definition we may substitute the word necessarily for constantly. Hume denies this positively, and from the empirical standpoint occupied by himself and Locke, no other answer was possible. If everything is derived from experience, the idea of cause must be so derived also. If there were nothing but change and uncertainty in nature, the idea of causality would never have arisen. But instead of this we do actually observe a certain uniformity in the sequences of events. We do not find any power or necessary connection binding the effect to the cause, we only find that the one does in fact follow the other. Hence it is that men ' acquire by long ^ Enquiry Concerning Human Understanding, sect. vii. pt. 2. * lb. sect. viii. i. 342 MODERN PHILOSOPHY. habit such a turn of mind, that upon the appearance of the cause they immediately expect with assurance its usual attendant, and hardly conceive it possible that any other event could result from it. ' But were the power or energy of any cause dis- coverable by the mind, we could foresee the effect even without experience, and might at first pro- nounce with certainty concerning it, by the mere dint of thought and reasoning. In reality, there is no part of matter that does ever, by its sensible qualities, discover any power or energy, or give us ground to imagine that it could produce anything, or be fol- lowed by any other object, which we could deno- minate its effect. . . . The scenes of the universe are continually shifting, and one object follows another in an uninterrupted succession ; but the power or force which actuates the whole machine is entirely concealed from us, and never discovers itself in any of the sensible qualities of body. ' We have no idea of this connexion, nor even any distinct notion what it is we desire to know, when we endeavour at a conception of it. We say, for instance, that the vibration of this string is the cause of this particular sound. But what do we mean by that affirmation 1 We either mean that this vibration is foUoivecl hy this sound, and that all similar vibra- tions have heen folloived hy similar sounds ; or, that this vibration is follotved, hy this sound, and that upon the ap2^earance of one the mind anticipates the senses, and forms immediately an idea of the other. We may consider the relation of cause and effect in either of these two lights, but beyond these we have no idea of it. ' But there still remains one method of avoiding this conclusion. . . . When any natural object or event HUME. 343 is presented, it is impossible for us, by any sagacity or penetration, to discover or even conjecture, with- out experience, what event will result from it, or to carry our foresight beyond that object which is im- mediately present to the memory and senses. Even after one instance or experiment, where we have observed a particular event to follow upon another, we are not entitled to form a general rule or foretell what will happen in like cases, it being justly es- teemed an unpardonable temerity to judge of the whole course of natiu-e from one single experiment, however accurate or certain. But when one par- ticular species of event has always, in all instances, been conjoined with another, we make no longer any scruple of foretelling one upon the appearance of the other, and of employing that reasoning which can alone assure us of any matter of fact or existence. We then call the one object, Cause ; the other, j^ec^. We suppose that there is some connexion between them ; some power in the one by which it infallibly produces the other, and operates with the greatest certainty and strongest necessity. ' Shall we then assert that we are conscious of a power or energy in otir own minds, when, by an act or command of our will, we raise up a new idea, fix the mind to the contemplation of it, turn it on all sides, and at last dismiss it for some other idea, when we think that we have surveyed it with sufficient accuracy ? . . . But do we pretend to be acquainted with the nature of the human soul and the nature of an idea, or the aptitude of the one to produce the other 1 This is a real creation, a production of some- thing out of nothing ^ ; which implies a power so ' And therefore the realization of the idea of cause ; cf. ante, the view of the Greek sceptics. 344 MODERN PHILOSOPHY, great that it may seem at first sight beyond the reach of any being less than infinite. At least it must be owned that such a power is not felt, nor known, nor even conceivable by the mind. We only feel the event, namely the existence of an idea con- sequent to a command of the will ; but the manner in which this operation is performed, the power by which it is produced, is entirely beyond our com- prehension. ' The command of the mind over itself is hmited, as Avell as its command over the body.' The latter (which Locke had brought forward as the prototype of the idea of Cause) eludes our discernment as much as all the rest. ' The influence of vohtion over the organs of the body is a fact. . . . But the means by w^hich this is effected, the energy by which the will performs so extraordinary an operation, of this we' are so far from being immediately conscious, that it must for ever escape our most diligent enquiry. , . . Is there any principle in all nature more mysterious than the union of soul with body, by wdiich a sup- posed spiritual substance acquires such an influence over a material one, that the most refined thought is able to actuate the grossest matter 1 Were we empowered by a secret wish to remove mountaics or control the planets in their orbits, this extensive authority would not be more extraordinary nor more beyond our comprehension. . . . The immediate ob- ject of power in voluntary motion is not the mem- ber itself which is moved, but certain muscles and nerves and animal spirits, and perhaps something still more minute and unknown, through which the motion is successively propagated. . . . That the motion of the limbs follows the command of the will is a matter of common experience like other natural HUME. 345 events.' And as the vulgar do in the case of what is apparently miraculous, so philosophers think them- selves obliged in all cases to have resort to some invisible intelligent principle as the immediate cause of what is unexplained. ' Our authority over our sentiments and passions is much weaker than that over our ideas ; and even the latter authority is cir- cumscribed within very narrow boundaries. Will any one pretend to assign the ultimate reason of these boundaries, or show why the power is deficient in one case and not in another ? This self-command too is very different at diflPerent times. A man in health possesses more of it than one languishing with sickness. We are more master of our thoughts in the morning than in the evening ; fasting than after a full meal. Can we give any reason for these variations except experience V In short, the will by itself has no knowledge of its own powers or their source. ' It requires as certain experience as that of which we are possessed to convince us that such extraordinary effects do ever result from a simple act of volition.' To sum up the argument in his own w^ords : ' Every idea is copied from some preceding impres- sion or sentiment ; and when we cannot find any impression we may be certain that there is no idea. In all single instances of the operation of bodies or minds, there is nothing that produces any impression nor consequently can suggest any idea of power or necessary connexion. But when uniform instances appear, and the same object is always followed by the same event, we then begin to entertain the notion of cause or connexion. We then feel a new sentiment or impression, to wit, a customary connexion in the thought or imagination between 346 MODERN PHILOSOPHY. one object and its usual attendant ; and this sen- timent is the original of that idea which we seek for.' But the regularity of the course of nature up to a certain point supplies no logical ground for the expectation that the regularity must continue. Ex- perience can tell us nothing of the inner nature of bodies, which might change without any change in their sensible qualities. It is useless to say that my own conduct invalidates the doubt ; as a practical agent I may have no such difficulties, but as a philosopher I am justified in expressing the doubt, though I may have little hope of seeing it removed. ' It is certain that the most ignorant and stupid peasants, nay infants, nay, even brute beasts, improve by experience, and learn the qualities of natural objects by observing the effects which result from them. When a child has felt the sensation of pain from touching the flame of a candle, he will be care- ful not to put his hand near any candle ; but will expect a similar effect from a cause, which is similar in its sensible qualities and appearance. If you assert therefore that the understanding of the child is led into this conclusion by any process of argu- ment and ratiocination, I may justly require you to produce that argument, nor have you any pretence to refuse so equitable a demand. You cannot say that the argument is abstruse and may possibly escape your enquiry, since you confess that it is obvious to the capacity of a mere infants' But there is a connection of cause and effect met with in the animal world and ministering to the preservation, of the organism, which is not based upon practice or experience : ' These we denominate ^ Enquiry Concerning Human Understanding, sect. iv. HUME. 347 instincts, and are so apt to admire as something very extraordinary and inexplicable by all the disquisi- tions of human understanding. But our -wonder will, perhaps, cease or diminish when we consider that the experimental reasoning itself, which we possess in common with beasts and on which the whole conduct of life depends, is nothing but a species of instinct or mechanical power that acts in us unknown to ourselves, and in its chief operations is not directed by any such relation or comparison of ideas as are the proper objects of our intellectual faculties. Though the instinct be diiferent, yet still it is an instinct, which teaches a man to avoid the fire as much as that which teaches a bird with such exactness the art of incubation, and the whole economy and order of its nursery ^.' Both our practical and our speculative antici- pations of natural events thus display ' a kind of pre-established harmony between the course of na- tiure and the succession of our ideas ; and though the powers and forces by which the former is go- verned be wholly unknown to us, yet our thoughts and conceptions have still, we fi.nd, gone on in the same train with the other works of nature. Custom is that principle by which this correspondence has been effected, so necessary to the subsistence of our species and the regulation of our conduct in every circumstance and occurrence of human life. Had not the presence of an object instantly excited the idea of these objects commonly conjoined with it, all our knowledge must have been limited to the narrow sphere of our memory and senses ; and we should never have been able to adjust means to ends, or employ our natural powers either to the producing ^ Enquiry Concerning Human Understanding, sect. ix. 348 MODERN PHILOSOPHY. of good or avoiding of evil . . . This operation of the mind, by which we infer like eifects from like causes, and vice versa, is so essential to the subsistence of all human creatures, it is not probable tliat it could be trusted to the fallacious deductions of our reason, which is slow in its operations ; appears not, in any degree, during the first years of infancy; and at best is, in every age and period of human life, extremely liable to error and mistake. It is more conformable to the ordinary wisdom of nature to secure so necessary an act of the mind by some instinct or mechanical tendency, which may be in- fallible in its operations, may discover itself at the first appearance of life and thought, and may be in- dependent of all the laboured deductions of the un- derstanding. As nature has taught us the use of our limbs, without giving us the knowledge of the muscles and nerves by which they are actuated, so has she implanted in us an instinct which carries forward the thought in a correspondent course to that which she has established among external objects, though we are ignorant of those powers and forces on which this regular course and succession of objects totally depends \' Hume had thus reached the same result as the Greek sceptics, that the purjaose of knowledge was the presei'vation of human existence, and that it should therefore never venture beyond its proper boundaries and presume to fathom the eternal truths of metaphysics, among which the investigation of causes was to be reckoned, as this idea, in and by itself, is simply incomprehensible to man, besides heino- never realised in fact. The true business of o ' Enquiry Concerning Human Understanding, sect. v. HUME. 349 man is to reproduce in thought the sequences given by experience in a corresponding order, and not to meddle with the tedious methods of logical inferences or deduction. The Greek sceptics had substantially the same meaning when they contested the signum cle- monstrativum and accepted and extolled the signum memoriale. In the latter, according to them, the whole force of human knowledge was to be found, and beyond this it cannot go; smoke brings fire,l wounds death into remembrance. The mistake of the dogmatists is to see, in all these things, signs, which are to enable them to pierce into the im- penetrable nature of things. The germ of Hume's theory is thus contained in this fundamental view of theirs. But it is very interesting that the Greek sceptics should have been right in placing the seat of human superiority over brutes in these signa memo- rialia, and thus, perhaps, for the first time, virtually indicating the importance of language to thought ^ Human thought could reach no other than these negative results, from the starting-point of mere em- piricism. If, as Locke assiimed, the idea of cause, as well as everything else, was derived from without, then this idea itself is contingent, not necessary, and is therefore self-destructive. The scepticism of Hume in fact determined the disintegration of empiricism, and so prepared the way for profounder knowledge. We must now follow him into these realms of * Kai/ hwp.ev 8e dtatpepet-if toiv aWts, by which I carry out that determination, conform to the object, being then again in the same perplexity on account of the manner how I can know anything about it a priori ; or that the objects, or what is the same, the experience in which alone they are known (as given objects), must conform to those concepts. In the latter case, the solution becomes more easy, because experience, as a kind of knowledge, requires understanding, and I must therefore, even before objects are given to me, presuppose the rules of the understanding as existing within me a priori, these rules being ex- pressed in concepts a priori, to which all objects of experience must necessarily conform, and with which they must agree. With regard to objects, so [p. xviii] far as they are conceived by reason only, and con- ceived as necessary, and which can never be given in experience, at least in that form in which they are conceived by reason, we shah find that the attempts at conceiving them (for they must admit of being B b 2 372 SUPPLEMENT 11. coDceived) will furnish afterwards an excellent test of our new method of thought, according to which we do not know of things anything a ^priori, except what we ourselves put into them ^ This experiment succeeds as well as we could desire, and promises to metaphysic, in its first part, which deals with concepts a priori, of which the corresponding objects may be given in experience, the secure method of a science. For by thus [p. xix] changing our point of view, the possibility of know- ledge a priori can well be explained, and, what is still more, the laws which a priori lie at the founda- tion of nature, as the sum total of the objects of experience, may be supplied with satisfactory proofs, neither of which was possible with the procedure hitherto adopted. But there arises from^ this_ deduc- tion of our faculty of knowing a priori, as given in the first part of metaphysic, a somewhat startling result, apparently most detrimental to the objects of metaphysic that have to be treated in the second ' This method, borrowed from the student of nature, consists in our looking for the elements of pure reason in that ivliich can he confirmed or refuled by exjyeri-ment. Now it is impossible, in order to test the propositions of pure reason, particularly if they venture beyond all the limits of possible experience, to make any experi- ment with their objects (as in natural science) ; we can therefore only try with concepts and propositions which we admit a priori, by so contriving that the same objects may be considered on one side as objects of the senses and of the understanding in expe- rience, and, on the other, as objects which are only thought, intended, it may be, for the isolated reason which strives to go beyond all the limits of experience. This gives us two different sides to be looked at ; and if we find that, by looking on things from that twofold point of view, there is an agreement with the principle of pure reason, while by admitting one point of view only, there arises an inevitable conflict with reason, then the ex- periment decides in favour of the correctness of that distinction. SUPPLEMENT II. 373 part, namely the impossibility of going with it beyond the frontier of possible experience, which is precisely the most essential purpose of metaphysical [p. xx] science. But here we have exactly the experiment which, by disproving the opposite, establishes the truth of our first estimate of the knowledge of reason a friori, namely, that it can refer to phenomena only, but must leave the thing by itself as unknown to us, though as existing by itself For that which impels us by necessity to go beyond the limits of experience and of all phenomena, is the unconditioned, which reason postulates in all things by themselves, by necessity and by right, for everything conditioned, so that the series of conditions should thus become com- plete. If then we find that, under the supposition of our experience conforming to the objects as things by themselves, it is imjyossihle to conceive the uncondi- tioned witJioui contradiction, while, under the suppo- sition of our representation of things, as they are given to us, not conforming to them as things by themselves, but, on the contrary, of the olyects con- forming to our mode of representation, that contra- diction vanishes, and that therefore the unconditioned must not be looked for in things, so far as we know them (so far as they are given to us), but only so far as we do not know them (as things by themselves), we clearly perceive that, what we at first assumed tenta- tively only, is fully confirmed ^- [ p. xxi] ' This experiment of pure reason has a great similarity with that of the chemists, which they sometimes call the experiment of reduction, or the synthetical process in general. The analysis of the metaphysician divided pure knowledge a priori into two very heterogeneous elements, namely, the knowledge of things as phe- nomena, and of things by themselves. Dialectic combines these two again, to bring them into harmony with the necessary idea of 374 SUPPLEMENT II. ' But, after all progress in the field of the supersen- suous has thus been denied to speculative reason, it is still open to us to see, whether in the practical know- ledge of reason data may not be found which enable us to determine that transcendent concept of the uncon- ditioned which is demanded by reason, in order thus, according to the wish of metaphysic, to get beyond the limits of all possible experience, by means of our knowledge a jmori, which is possible to us for prac- tical purposes only. In this case, speculative reason has at least gained for us room for such an extension of knowledge, though it had to leave it empty, so that we are not only at liberty, but are really called upon to fill it up, if we are able, by practical data of reason \ [p- xxii] The very object of the critique of pure speculative reason consists in this attempt at changing the old procedure of metaphysic, and imparting to it the the unconditioTied, demanded by reason, and then finds that this harmony can never be obtained, except through the above distinc- tion, whicli therefore must be supposed to be true. ' In the same manner the laws of gravity, determining the movements of the heavenly bodies, imparted the character of established certainty to what Copei-nicus had assumed at first as an hypothesis only, and proved at the same time the invisible force (the Newtonian attraction) which holds the universe together, which would have remained for ever undiscovered, if Copernicus had not dared, by an hypothesis, which, though contradicting the senses, was yet true, to seek the observed movements, not in the heavenly bodies, but in the spectator. I also propose in this preface my own view of metaphysics, which has so many analogies with the Copernican hypothesis, as an hypothesis only, though, in the Critique itself, it is proved by means of our representations of space and time, and the elementary concepts of the understanding, not hypothetically, but apodictically ; for I wish that people should observe the first attempts at such a change, which must always be hypothetical. SUPPLEMENT II. 375 / secure method of a science, after having completely / revolutionized it, following the example of geometry ^ and physical science. That critique is a treatise on the method (Traite de la methode), not a system of the science itself ; but it marks out nevertheless the whole plan of that science, both with regard to its limits, ( and to its internal organisation. For pure [p. xxiii] / speculative reason has this peculiar advantage that it , is able, nay bound to measure its own powers, accord- ing to the different ways in which it chooses its own .objects, and to completely enumerate the different ways of choosing problems ; thus tracing a complete outline of a system of metaphysic. This is due to the fact that, with regard to the first point, nothing can be attributed to objects in knowledge a priori, except what the thinking subject takes from within itself; while, with regard to the second point, reason, so far as its principles of cognition are concerned, forms a separate and mdependent unity, in which, as in an organic body, every member exists for the sake of all others, and all others exist for the sake of the one, so that no principle can be safely applied in one relation, unless it has been carefully examined in all its rela- tions, to the whole employment of pure reason. Hence, too, metaphysic has this singular advantage, an ad- vantage which cannot be shared by any other science, in which reason has to deal with objects (for Logic deals only with the form of thought in general,) that, if it has once attained, by means of this critique, to the secure method of a science, it can completely compiehend the whole field of knowledge [p. xxiv] pertaining to it, and thus finish its work and leave it to posterity, as a capital that can never be added to, because it has only to deal with principles and the limits of their employment, which are fixed by those 376 SUPPLEMENT II. principles themselves. And this completeness becomes indeed an obligation, if it is to be a fundamental science, of which we must be able to say, ' nil actum reptitans, si quid superesset agendum.' But it will be asked, what kind of treasure is it which we mean to bequeath to posterity in jthis metaphysic of ours, after it has been purified by criti- cism, and thereby brought to a permanent condition ? After a superficial view of this work, it may seem that its advantage is negative only, warning us against venturing with speculative reason beyond the hmits of experience. Such is no doubt its primary use: but it becomes ])ositive, when we perceive that the principles with which speculative reason ventures beyond its limits, lead inevitably, not to an extension, but, if carefully considered, to a narrowing of the employment of reason, because, by indefinitely ex- tending the limits of sensibility, to which they [p. xxvj properly belong, they threaten entirely to supplant the pure (practical) employment of reason. Hence our critique, by limiting speculative reason to its proper sphere, is no doubt negative, but by thus removing an impediment, which threatened to narrow, or even entirely to destroy its practical employment, it is in reality oi jiositive, and of very important use, if only we are convinced that there is an absolutely necessary practical use of pure reason (the moral use), in which reason must inevitably go beyond the limits of sensi- bility, and though not requiring for this purpose the assistance of speculative reason, must at all events be assured against its opposition, lest it be brought in conflict with itself To deny that this service, which is rendered by criticism, is a positive advantage, would be the same as to deny that the police confers upon us any positive advantage, its principal occupa- SUPPLEMENT II. 377 tion being to prevent violence, which citizens have to apprehend from citizens, so that each may pursue his vocation in peace and security. We had established in the analytical part of our critique the following points : — First, that space and time are only forms of sensuous intuition, therefore conditions of the exist- ence of things, as phenomena only ; Secondly, that we have no concepts of the understanding, and there- fore nothing whereby we can arrive at the knowledge of things, except in so far as an intuition cor- [p. xxvi] responding to these concepts can be given, and conse- quently that we cannot have knowledge of any object, as a thing by itself, but only in so far as it is an object of sensuous intuition, that is, a phenomenon. This proves no doubt that all speculative knowledge of reason is limited to objects of experience ; but it should be carefully borne in mind, that this leaves it perfectly open to us, to thinh the same objects as things by themselves, though we cannot know them ^. For otherwise we should arrive at the absurd conclu- sion, that there is phenomenal appearance [p. xxvii] without something that appears. Let us suppose that the necessary distinction, established in our critique, between things as objects of experience and the same things by themselves, had not been made. In that ' In oi'der to know an object, I must be able to prove its possi- bility, either from its reality, as attested by experience, or a priori, by means of reason. But I can think whatever I please, pro- vided only I do not contradict myself, that is, provided my con- ception is a possible thought, though I may be unable to answer for the existence of a corresponding object in the sum total of all possibilities. Before I can attribute to such a concept objective reality (real possibility, as distinguished from the former, which is purely logical), something more is required. This something more, however, need not be sought for in the sources of theoretical know- ledge, for it may be found in those of practical knowledge also. 378 SUPPLEMENT II. case, the principle of causality, and with it the mecha- nism of nature, as determined by it, would apply to all things in general, as efficient causes. I should then not be able to say of one and the same being, for instance the human soul, that its will is free, and, at the same time, subject to the necessity of nature, that is, not free, without involving myself in a pal- pable contradiction : and this because I had taken the soul, in both propositions, in one and the same sense, namely, as a thing in general (as something by itself), as, without previous criticism, I could not but take it. If, however, our criticism was true, in teach- ing us to take an object in two senses, namely, either as a phenomenon, or as a thing by itself, and if the deduction of our concepts of the understanding was correct, and the principle of causality applies to things only, if taken in the first sense, namely so far as they are objects of ex2:)erience, but not to things, if taken in their second sense, we can, without any con- tradiction, think the same will as phenomenal (in visible actions) as necessarily conforming to [p- xxviii] the law of nature, and so far, not free, and yet, on the other hand, if belonging to a thing by itself, as not sub- ject to that law of nature, and therefore /ree. Now it is quite true, that I may not hnoiv my soul, as a thing by itself, by means of speculative reason (still less through empirical observation), and consequently may not know freedom either, as the quality of a being to which I attribute effects in the world of sense, because, in order to do this, I should have to know such a being as existing, and yet as not determined in time (which, as I cannot provide my concept with any intuition, is impossible). This, however, does not prevent me from thinhing freedom ; that is, my repre- sentation of it contains at least no contradiction within SUPPLEMENT 11. 379 itself, if only our critical distinction of the two modes of representation (the sensible and the intelligible), and the consequent limitation of the concepts of the pure understanding, and of the principles based on them, has been properly carried out. If, then, morality necessarily presupposes freedom (in the strictest sense) as a property of our will, producing, as a j^riori data of it, practical principles, belonging originally to our reason, which, without freedom, would be absolutely impossible, while speculative reason proves [p. xsix] that such a freedom cannot even be thought, the former suppogition, namely, the moral one, would necessarily have to yield to another, the opposite of which involves a palpable contradiction, so that free- dom, and with it morality (for its opposite contains no contradiction, unless freedom is presupposed), would have to make room for the mechanism of nature. Now, however, as morality requires nothing but that freedom should only not contradict itself, and that, though unable to understand, we should at least be able to think it, there being no reason why freedom should interfere with the natural mechanism of the same act (if only taken in a different sense), the doctrine of morality may well hold its place, and the doctrine of nature may hold its place too, which would have been impossible, if our critique had not previously taught us- our inevitable ignorance with regard to things by themselves, and limited everything, which we are able to hnoiv theoretically, to mere phenomena. '. The same discussion as to the positive advantage to be derived from the critical principles of pure reason, might be repeated with regard to the concept of Ood, and of the simi^le nature of our soul ; but, for the sake of brevity, I shall pass this by. We have seen, therefore, that I am not allowed even to [p. xxx] 380 SUPPLEMENT II. assume, for the sake of the necessary practical em- ployment of my reason, God, freedom, and immortality, if I cannot deprive specvilative reason of its preten- sions to transcendent insights, because reason, in order to arrive at these, must use principles which are intended originally for objects of possible experi- ence only, and which, if in spite of this, they are applied to what cannot be an object of experience, really change this into a phenomenon, thus rendering all jjractical exteiision of pure reason impossible. I had therefore to remove knowledge, in order to make room for belief. For the dogmatism of meta- physic, that is, the presumption that it is possible to achieve anything in metaphysic without a previous criticism of pure reason, is the source of all that unbelief, which is always very dogmatical, and wars against all morality. If then, it may not be too difficult to leave a be- quest to posterity, in the shape of a systematical metaphysic, carried out according to the critique of pure reason, such a bequest is not to be considered therefore as of little value, whether we regard the improvement which reason receives through the secure method of a science, in place of its groundless groping and uncritical vagaries, or whether [p. xxxi] we look to the better employment of the time of our enquiring youth, who, if brought up in the ordinary dogmatism, are early encouraged to indulge in easy speculations on things of which they know nothing, and of which they, as little as anybody else, will ever understand anything ; neglectiug the acquirement of sound knowledge, while bent on the discovery of new metaphysical thoughts and opinions. The greatest benefit however will be, that such a work will enable us to put an end for ever to all objections to morality SUPPLEMENT II. 38 1 and religion, according to the Socratic method, namely, by the clearest proof of the ignorance of our oppo- nents. Some kind of metaphysic has always existed, and will always exist, and with it a dialectic of pure reason, as being natural to it. It is therefore the first and most important task of philosophy to deprive metaphysic, once for all, of its pernicious influence, by closing up the sources of its errors. In spite of these important changes in the whole field of science, and of the losses which specvilative reason must suffer in its fancied possessions, all general hviman interests, and all the advan- [p. xxxii] tages which the world hitherto derived from the teachings of pure reason, remain just the same as before. The loss, if any, affects only the mono])oly of the schools, and by no means the interests of humanity. I appeal to the staunchest dogmatist, whether the proof of the continued existence of our soul after death, derived from the simplicity of the substance, or that of the freedom of the will, as opposed to the general mechanism of nature, derived from the subtle, but iaefficient, distinction between subjective and objec- tive practical necessity, or that of the existence of God, derived from the concept of an Ens realissimum (the contingency of the changeable, and the necessity of a prime mover), have ever, after they had been started by the schools, penetrated the public mind, or exer- cised the shfichtest influence on its convictions^ If this has not been, and in fact could not be so, on account of the unfitness of the ordinary understand- ing for such subtle speculations ; and if, on the con- trary, with regard to the first point, the hope of a future life has chiefly rested on that peculiar cha- racter of human nature, never to be satisfied by what is merely temporal (and insufficient, therefore, for the 382 SUPPLEMENT II. character of its whole destination) ; if with regard to the second, the clear consciousness oi freedom [p. xxxiii] was produced only by the clear exhibition of duties, in opposition to all the claims of sensuous desires ; and if, lastly, with regard to the third, the behef in a great and wise Author of the loorld has been supported en- tirely by the wonderful beauty, order, and providence, everyMdiere displayed in nature, then this possession re- mains not only undisturbed, but acquires even greater authority, because the schools have now been taught, not to claim for themselves any higher or fuller insight on a point which concerns general human interests, than what is equally within the reach of the great mass of men, and to confine themselves to the elaboration of these universally comprehensible, and, for moral purposes, quite sufficient proofs. The change therefore affects the arrogant pretensions of the schools only, which would fain be considered as the only judges and depositaries of such truth (as they are, no doubt, with regard to many other subjects), allowing to the public its use only, and trying to keep the key to themselves, quod mecum nescit, solus vult scire videri. At the same time fuU satisfac- tion is given to the more moderate claims [p. xxxiv] of speculative philosophers. They still remain the exclusive depositors of a science which benefits the masses without their knowing it, namely the critique of I'eason. That critique can never become popular, nor does it need to be so, because, if on the one side the public has no understanding for the fine-drawn arguments in support of useful truths, it is not troubled on the other by the equally subtle objections. It is different with the schools which, m the same way as every man who has once risen to the height of speculation, must know both the pro's and the con's, SUPPLEMENT II. 383 and are bound, by means of a careful investigation of the rights of speculative reason, to prevent, once for all, the scandal which, sooner or later, is sure to be caused even to the masses, by the quarrels in which metaphysicians (and, as such, theologians also) become involved, if ignorant of our critique, and by which their doctrine becomes in the end entirely perverted. Thus, and thus alone, can the very root be cut oflF of materialism, fatalism, atheism, free-thinking tmhelief fanaticism, and superstition, which may become uni- versally injurious, and finally of idealism and scejoticism also, which are dangerous rather to the schools, and can scarcely ever penetrate into the public. If [p. xxxv] governments think proper ever to interfere with the affairs of the learned, it would be far more consistent ■with their wise regard for science as well as for society, to favour the freedom of such a criticism by which alone the labours of reason can be established on a firm footing, than to support the ridiculous despotism of the schools, which raise a loud clamour of public dan- ger, whenever the cobwebs are swept away of which the public has never taken the slightest notice, and the loss of which it can therefore never perceive. Our critique is not opposed to the dogmatical pro- cedure of reason, as a science of pure knowledge (for this must always be dogmatical, that is, derive its proof from sure principles a priori), but to dogmatism only, that is, to the presumption, that it is possible to make any progress with pure (philosophical) knowledge, consisting of concepts, and guided by principles, such as reason has long been in the habit of employing, without first enquiring in what way, and by what right, it has come possessed of them. Dogmatism is therefore the dogmatical procedure of pure reason, without a previous criticism of its own powers ; and 384 SUPPLEMENT II. our opposition to this is not intended to defend either that loquacious shallowness which arrogates [p. xxxvi] to itself the good name of popularity, much less that scepticism which makes short work with the whole of metaphysic. On the contrary, our critique is meant to form a necessary preparation in support of a thoroughly scientific system of metaphysic, which must neces- sarily be carried out dogmatically and strictly syste- matically, so as to satisfy all the demands, not so much of the public at large, as of the schools, this being an indispensable condition, as it has undertaken to carry out its work entirely a priori, and thus to the complete satisfaction of speculative reason. In the execution of this plan, as traced out by the critique, that is, in a future system of metaphysic, we shall have to follow in the strict method of the celebrated Wolf, the greatest of all dogmatic philosophers, who first showed (and by his example called forth, in Germany, that spirit of thoroughness, which is not yet extinct) how the secure method of a science could be attained only by a legitimate establishment of principles, a clear definition of concepts, an attempt 'at strictness of proof, and an avoidance of all bold combinations in concluding. He was therefore most eminently quali- fied to raise metaphysics to the dignity of a science, if it had only occui-red to him, by criticism of the organum, namely of pure reason itself, first to prepare his field, — an omission to be ascribed, not so [p. xxxvii] much to himself as to the dogmatical spirit of his age, and with regard to which the philosophers of his own, as well as of all previous times, have no right to reproach each other. Those who reject, at the same time, the method of Wolf, and the procedure of the critique of pure reason, can have no other aim but to shake off the fetters of science altogether, SUPPLEMENT II. 385 and thus to change work into play, conviction into opinion, and philosophy into philodoxy. I With regard to this second edition, I have tried, as was but fair, to do all I could in order to remove, as far as possible, the difficulties and obscurities which, not perhaps without my fault, have misled even acute thinkers in judging of my book. In the pro- positions themselves, and their proofs, hkewise in the form and completeness of the whole plan, I have found nothing to alter, which is due partly to the long-continued examination to which I had subjected them, before submitting them to the pubhc, and partly to the nature of the subject itself For pure speculative reason is so constituted that it forms a true organism, in which everything is organic, the whole being there for the sake of every [p. xxsviii] part, and every part for the sake of the whole, so that the smallest imperfection, whether a fault or a defi- ciency, must inevitably betray itself in use. I venture to hope that this system will maintain itself un- changed for the future also. It is not self-conceit which justifies me in this confidence, but the experi- mental evidence produced by the identity of the result, whether we proceed progressively from the smallest elements to the whole of pure reason, or retrogressively from the whole (for this also is given by the practical objects of reason) to every single part ; the fact being, that an attempt at altering even the smallest item produces at once contradictions, not only in the system, but in human reason in general. With regard to the style, however, much remains to be done ; and for that purpose, I have VOL. I. C C 386 SUPPLEMENT II. endeavoured to introduce several improvements mto this second edition, which are intended to remove, first, misapprehensions in the Esthetic, especially with regard to the concept of time : secondly, obscurities in the deduction of the concepts of reason : thirdly, a supposed want of sufficient evidence, in provmg the propositions of the pure understanding : fourthly, the false interpretation put on the paralogisms with which we charged rational psychology. To this point (only to the end of the first chapter of transcendental Dialectic) do the changes of style and repre- [p. xxxix] sentation^ extend, and no further. Time was too 1 The only thing which might be called an addition, though in the method of proof only, is the new refutation of 2}'7 ■ 46 59 392 SUPPLEMENT HI. PAGE Conclusion of transcendental Esthetic . -73 Second Part. Transcendental Logic . 74-732 Introduction. The idea of a transcendental Logic ...... 74-88 I. Of Logic in general . . . -74 II. Of transcendental Logic . . -79 III. Of tlie division of general Logic into analytical and dialectical . . .82 ly. Of the division of transcendental Logic into transcendental Analytic and Dia- lectic . . . . . .87 First Division. Transcendental Analytic 89-349 First Book. Analytic of concepts . 90-169 First Chapter. Method of discovering all pure concepts of the understanding . -91 First Section. Of the logical use of the understanding in general . . -92 Second Section. Of the logical function of the understanding in judgments. § 9 . 95 Third Section. Of the pure concepts of the understanding, or of the Categories. ^ 10-12 ....... 102 Second Chapter. Of the deduction of the pure concepts of the understanding . .116 First Section. Of the principles of a tran- scendental deduction in generah ^13 .116 Transition to a transcendental deduction of the Categories. ^14 . . . .124 Second Section. Transcendental deduc- tion of the pure concepts of the under- standing. ^ 15-27 . . . . .129 Second Book. Analytic of principles (tran- scendental doctrine of the faculty of judg- ment) 169-349 SUPPLEMENT III. 393 PAGE Introduction. Of the transcendental faculty of judgment in general . . . • 171 First Chapter. Of the schematism of the piire concepts of the tmderstanding . . 1 76 Second Chapter. System of all principles of the pure understanding . . . .187 First Section. Of the highest principle of all analytical judgments . . .189 Second Section. Ofthe highest principles of all synthetical judgments . . ■ 193 Third Section. Systematical representa- tion of aU synthetical principles of the pure understanding . . . 197-294 1. Of the Axioms of intuition . . .202 2. Anticipations of perception . . . 207 3. Analogies of experience . . .218 First Analogy. Principle of the per- manence of substance . . .224 Second Analogy. Principle ofthe suc- cession of time, according to the law of causality . . . . -232 Third Analogy. Principle of coexist- ence, according to the law of re- ciprocity . . . . -256 4. Postulates of empirical thought in general ...... 265 General note on the system of the prin- ciples ...... 288 Third Chapter. On the ground of distinction of all subjects into phenomena and noumena 294 Appendix. On the amphiboly of reflective concepts owing to the confusion of the em- pirical with the transcendental use of the understanding . . . . . • 316 394 SUPPLEMENT III. PAOB Second Division. Transcendental Dialectic 349-732 Introduction ..... 349-366 I. Of transcendental illusion . . . 349 II. Of pure reason as the seat of transcendental illusion 355 A. Of reason in general . . -355 B. Of the logical use of reason . . 359 C. Of the pure use of reason . . 362 First Book. Of the concepts of pure reason 366 First Section. Of ideas in general . . 368 Second Section. Of transcendental ideas 377 Third Section. System of transcendental ideas .... ... 390 Second Book. Of the dialectical conclusions of pure reason ..... 396-732 First Chapter. Of the Paralogisms of pure reason . ...... 399 General note on the transition from rational psychology to cosmology . . . .428 Second Chapter. The Antinomy of piire reason . . . . . . .432 F i r s t S e c t i o n. Sy stem of cosmological ideas 435 Second Section. Antithetic of piure reason 448 First Antinomy . . . . .454 Second Antinomy . . . . .462 Third Antmomy . . . . .472 Fourth Antinomy ..... 480 Third Section. Of the interest of reason in these confhcts ...... 490 Fourth Section. Of the transcendental problems of pure reason and the absolute necessity of their solution .... 504 Fifth Section. Sceptical representation of the cosmological questions in the four tran- scendental ideas . . . . .513 SUPPLEMENT III. 395 PAGE Sixth Section. Transcendental idealism as the key to the solution of cosmological Dialectic . . . . . . .518 Seventh Section. Critical decision of the cosmological conflict of reason with itself . 525 Eighth Section. The regulative principle of pure reason with regard to the cosmo- logical ideas . . . . . -536 Ninth Section. Of the empirical use of the regulative principle of reason with re- gard to all cosmological ideas . . -543 I. Solution of the cosmological idea of the totality of the composition of phe- nomena of an universe . . -545 II. Solution of the cosmological idea of the totality of the division of a whole given in intuition . . . -551 Concluding remarks on the solution of the transcendental mathematical ideas, and prehminary remarks for the solu- tion of the transcendental dynamical ideas ...... 556 III. Solution of the cosmological ideas of the totahty of the derivation of cosmical events from their cavises . . .560 Possibihty of causality throvigh freedom 566 Explanation of the cosmological idea of freedom in connection with the general necessity of nature . . . -570 IV. Solution of the cosmological idea of the totality of the dependence of phe- nomena with regard to their exist- ence in general . . . -587 Concluding remarks on the whole an- tinomy of pure reason . . . 593 396 SUPPLEMENT III. PAGE Third Chapter. The ideal of pure reason . 595 First Section. Of the ideal in general . 595 Second Section. Of the transcendental ideal ....... 599 Third Section. Of the arguments of specu- lative reason m proof of the existence of a Supreme Being . . . . .611 Fourth Section. Of the impossibility of an ontological proof of the existence of God 620 Fifth Section. Of the impossibility of a cosmological proof of the existence of God . 631 Discovery and explanation of the dialectical illusion in all transcendental proofs of the existence of a necessary Being . . . 642 Sixth Section. Of the impossibility of the physico-theological proof .... 648 Seventh Section. Criticism of all th eology based on speculative principles of reason . 659 Appendix to the transcendental Dialectic . 670 Of the regulative use of the ideas of pure reason ....... 670 Of the fiinal aim of the natural Dialectic of human reason . . . . . -697 II. Transcendental Doctrine of Method. 733-884 Introduction ...... 735 First Chapter. The discipline of pure reason ....... 736-823 First Section. The discipline of pure reason in its dogmatical use . . . 740 Second Section. The discipline of pure reason in its polemical use . . .766 Of the impossibility of a sceptical satisfac- tion of pure reason in conflict with itself . 786 Third Section. The disciphne of pure reason with regard to the hypotheses . 797 SUPPLEMENT III. 397 PAGE Fourth Section. The discipline of pure reason with regard to its proofs . .810 Second Chapter. The canon of pure reason ...... 823-884 First Section. Of the ultimate aim of the pure use of our reason . . .825 Second Section. Of the ideal of the Summum Bonum, as determining the ulti- mate aim of Pure Eeason . . . .832 Third Section. Of trowing, knowing, and believing ...... 848 Third Chapter. The architectonic of pure reason ....... 860 Fourth Chapter, The History of pure reason ....... 880 SUPPLEMENT lY. [See vol. li. p. i] INTKODUCTION. I. Of the Difference between pure and empirical Knoivledge. That all our knowledge begins with experience there can be no doubt. For how should the faculty of knowledge be called into activity, if not by objects which affect our senses, and which either produce repre- sentations by themselves, or rouse the activity of our understanding to compare, to connect, or to separate them ; and tlius to convert the raw material of oiu: sensuous impressions into a knowledge of objects, which we call experience 1 In respect of time, there- fore, no knowledge within us is antecedent to ex- perience, but all knowledge begins with it. But although all our knowledge begins with ex- perience, it does not follow that it arises from experi- ence. For it is quite possible that even our empirical experience is a compound of that which we receive through impressions, and of that which our own faculty of knowledge (incited only by sensuous impressions), supplies from itself, a supplement which we do not distinguish from that raw material, until long practice has roused our attention and rendered us capable of separating one from the other. It is therefore a question which deserves at least SUPPLEMENT IV. 399 closer investigation, and cannot be disposed of at first sight, whetlaer there exists a knowledge independent of experience, and even of all impressions of the senses 1 Such knowledge is called a priori, and dis- tinguished from enipirical knowledge, which has its sources a jposteriori, that is, in experience. This term a priori, however, is not jet definite enough to indicate the full meaning of our question. For people are wont to say, even with regard to knowledge derived from experience, that we have it, or might have it, a priori, because we derive it from experience, not immediately, but from a general rule, which, however, has itself been derived from ex- perience. Thus one would say of a person who undermines the foundations of his house, that he might have known a priori that it would tumble down, that is, that he need not wait for the ex- perience of its really tumbling down. But still he could not know this entirely a priori, because he had first to learn from experience that bodies are heavy, and will fall when their supports are taken away. We shall therefore, in what follows, understand by knowledge a priori knowledge which is ahsolutely independent of all experience, and not of this or that experience only. Opposed to this is empirical know- ledge, or such as is possible a posteriori only, that is, by experience. Knowledge a priori, if mixed up with nothing empirical, is called pure. Thus the proposition, for example, that every change has its cause, is a proposition a priori, but not pure : because change is a concept which can only be derived from experience. 400 SUPPLEMENT IV. II. We are in possession of certain Cognitions a priori, and even the ordinary understanding is never without them. All depeods here on a criterion, by which we may safely distinguish between pure and empirical know- ledge. Now experience teaches us, no doubt, that something is so or so, but not that it cannot be diiferent. First, then, if we have a proposition, which is thought, together with its necessity, we have a judgment a priori ; and if, besides, it is not derived from any proposition, except such as is itself again considered as necessary, we have an absolutely a priori judgment. Secondly, experience never im- parts to its judgments true or strict, but only as- sumed or relative universality (by means of induc- tion), so that we ought always to say, so far as we have observed hitherto, there is no exception to this or that rule. If, therefore, a judgment is thought with strict univeisahty, so that no exception is ad- mitted as possible, it is not derived from experience, but valid absolutely a p)riori. Empirical universality, therefore, is only an arbitrary extension of a validity which applies to most cases, to one that applies to all : as, for instance, m the proposition, all bodies are heavy. If, on the contrary, strict universaHty is essential to a judgment, this always points to a special soui'ce of knowledge, namely, a faculty of knowledge a priori. Necessity, therefore, and strict universality are safe criteria of knowledge a j)riori, and are in- separable one from the other. As, however, in the use of these criteria, it is sometimes easier to show the empirical limitation than the contingency of SUPPLEMENT IV. 4OI judgments, and as it is sometimes more convincing to prove the unlimited universality whicli we attri- bute to a judgment than its necessity, it is advisable to use both criteria separately, each being by itself infalhble. I That there really exist in our knowledge such necessary, and in the strictest sense universal, and therefore, pure judgments a priori, is easy to show. If we want a scientific example, we have only to look to any of the propositions of mathematics ; if we want one from the sphere of the ordinary under- standing, such a proposition as that each change must have a cause, will answer the purpose ; nay, in the latter case, even the concept of cause contains so clearly the concept of the necessity of its connection with an effect, and of the strict universality of the rule, that it would be destroyed altogether if we attempted to derive it, as Hume does, from the frequent concomitancy of that which happens with that which precedes, and from a habit arising thence, — therefore from a purely subjective necessity of con- necting representations. It is possible even, with- out having recourse to such examples in proof of the reality of pure propositions a priori within our knowledge, to prove their indispensabihty for the possibility of experience itself, thus proving it a priori. For whence should experience take its certainty, if all the rules which it follows were always again and again empirical, and therefore contingent and hardly fit to serve as first principles ? For the present, however, we may be satisfied for having shown the pure employment of the faculty of our knowledge as a matter of fact, with the criteria of it. Not only in judgments, however, but even in certain concepts, can we show their origin a priori. VOL. I. D d 402 SUPPLEMENT IV. Take away, for example, from the concept of body, as supplied by experience, everything that is em- pirical, one by one ; such as colour, hardness, or softness, weight, and even impenetrability, and there still remains the space which the body (now entirely vanished) occupied : that you cannot take away. And in the same manner, if you remove from your empirical concept of any object, corporeal or in- corporeal, all properties which experience has taught you, you cannot take away from it that property by which you conceive it as a substance, or inherent in a substance (although such a concept contains more determinations than that of an object in general). Convinced, therefore, by the necessity with which that concept forces itself upon you, you will have to admit that it has its seat in your faculty of know- ledge a priori. SUPPLEMENT Y. [see voi. ii. p. v] Empikical judgments, as such, are all synthetical ; for it would be absurd to found an analytical judg- ment on experience, because, in order to form such a judgment, I need not at all step out of my concept, or appeal to the testimony of experience. That a body is extended, is a proposition perfectly certain a 'priori, and not an empirical judgment. For, before I call in experience, I am already m possession of all the conditions of my judgment in the concept of body itself I have only to draw out from it, ac-^ cording to the principle of contradiction, the required predicate, and I thus become conscious, at the same time, of the necessity of the judgment, which ex- perience could never teach me. But, though I do not include the predicate of gravity in the general concept of body, that concept, nevertheless, indicates an object of experience through one of its parts : so that I may add other parts also of the same experience, besides those which belonged to the former concept. I may, first, by an analytical process, realise the concept of body, through the predicates of extension, impermeability, form, &c., all of which are contained in it. Afterwards I expand my knowledge, and looking back to the experience from which my con- cept of body was abstracted, I find gravity always connected with the before mentioned predicates, and therefore I add it synthetically to that concept as a predicate. It is, therefore, experience on which the possibihty of the synthesis of the predicate of D d2 404 SUPPLEMENT V. gravity with the concept of body is founded : be- cause both concepts, though neither of them is con- tained in the other, belong to each other, though accidentally only, as parts of a whole, namely, of experience, which is itself a synthetical connection of intuitions. SUPPLEMENT YL [See vol. n. p. 9] V. In all theoretical Sciences of reason synthetical Judg- ments a priori are contained as principles. I. All mathematical judgments are synthetical. This proposition, though incontestably certain, and very important to us for the future, seems to have hitherto escaped the observation of those who are engaged in the anatomy of human reason : nay, to be directly opposed to all their conjectures. For as it was found that aU mathematical conclusions pro- ceed according to the principle of contradiction (which is required by the nature of all apodictic certainty), it was supposed that the fundamental principles of mathematics also rested on the authority of the same principle of contradiction. This, however, was a mistake : for though a synthetical proposition may be understood according to the principle of contra- diction, this can only be if another synthetical pro- position is presupposed, from which the latter is deduced, but never by itself First of all, we ought to observe, that mathematical propositions, properly so called, are always judgments a priori, and not empirical, because they carry along with them neces- sity, which can never be deduced from experience. If people should object to this, I am quite willing to confine my statement to ptire mathematics, the very concept of which imphes that it does not contain empirical, but ordy pure knowledge a priori. At first sight one might suppose indeed that the proposition 7 + 5=12 is merely analytical, following, according to the principle of contradiction, from the concept of a sum of 7 and 5. But, if we look more 4o6 SUPPLEMENT Vt. closely, we sliall find that the concept of the sum of 7 and 5 contains nothing beyond the union of both sums into one, whereby nothing is told us as to what this single number may be which combines both. We by no means arrive at a concept of Twelve, by thinking that union of Seven and Five ; and we may analyse our concept of such a possible sum as long as we will, still we shall never discover in it the concept of Twelve. We must go beyond these con- cepts, and call in the assistance of the intuition cor- responding to one of the two, for instance, our five fingers, or, as Segner does in his arithmetic, five points, and so by degrees add the units of the Five, given in intuition, to the concept of the Seven. For I first take the number 7, and taking the intuition of the fingers of my hand, in order to form with it the concept of the 5, I gradually add the units, which I before took together, to make up the number 5, by means of the image of my hand, to the number 7, and I thus see the number 12 arising before me. That 7 should be added to 5 was no doubt imphed in my concept of a sum 74-5, but not that that sum should be equal to 12. An arithmetical proposition is, therefore, always synthetical, which is seen more easily stiU by taking larger numbers, where we clearly perceive that, turn and twist our conceptions as we may, we could never, by means of the mere analysis of our concepts and without the help of in- tuition, arrive at the sum that is wanted. Nor is any proposition of pure geometry analytical. That the straight line between two points is the shortest, is a synthetical proposition. For my concept of straight contains nothing of magnitude (quantity), but a quahty only. The concept of the shortest is, therefore, purely adventitious, and cannot be deduced SUPPLEMENT VI. 407 from the concept of the straight hne by any analysis whatsoever. The aid of intuition, therefore, must be called in, by which alone the synthesis is possible. [It is true that some few propositions, presupposed by the geometrician, are really analytical, and depend on the principle of contradiction : but then they serve only, like identical propositions, to form the chain of the method, and not as principles. Such are the propositions, a = a, the whole is equal to itself, or [a-\-l))>a, that the whole is greater than its part. And even these, though they are valid according to mere concepts, are only admitted in mathematics, because they can be represented in in- tuition Kj What often makes us believe that the predicate of such apodictic judgments is contained in our concept, and the judgment therefore analytical, is merely the ambiguous character of the expression. We are told that we ought to join in thought a certain predicate to a given concept, and this ne- cessity is inherent in the concepts themselves. But the question is not what we ought to join to the given concept, but what we really think in it, though confusedly only, and then it becomes clear that the predicate is no doubt inherent in those concepts by necessity, not, however, as thought in the concept itself, but by means of an intuition, which must be added to the concept. 2. Natural science [physica) contains synthetical judgments a priori as princij>les. I shall adduce, as examples, a few propositions only, such as, that in aU changes of the material world the quantity of matter always remains unchanged : or that in all ' This paragraph from It is true to intuition seems to have been a marginal note, as shown by Dr. Vaihinger. See Translator's Preface, p. lii. 408 SUPPLEMENT VI. communication of motion, action and reaction must always equal each other. It is clear not only that both convey necessity, and that, therefore, their origin is a priori, but also that they are synthetical propositions. For in the concept of matter I do not conceive its permanency, but only its presence in the space which it fills. I therefore go beyond the con- cept of matter in order to join something to it a priori, which I did not before conceive in it. The proposition is, therefore, not analytical, but syntheti- cal, and yet a priori, and the same applies to the other propositions of the pure part of natural science. 3. Metaphysic, even if we look upon it as hitherto a tentative science only, which, however, is indispens- able to us, owing to the very nature of human reason, is meant to contain synthetical hnoivledge a priori. Its object is not at all merely to analyse such con- cepts as we make to ourselves of things a priori, and thus to explain them analytically, but to expand our knowledge a priori. This we can only do by means of concejjts which add something to a given concept that was not contained in it; nay, we even attempt, by means of synthetical judgments a priori, to go so far beyond a given concept that experience itself cannot follow us : as, for instance, in the proposition that the world must have a first beginning. Thus, according at least to its intentions, metaphysic con- sists merely of synthetical propositions a priori. VI. Tlie general Problem of pure Reason. Much is gained if we are able to bring a number of investigations under the formula of one single problem. For we thus not onlv facilitate our own SUPPLEMENT VI. 409 work by defining it accurately, but enable also every- body else who likes to examine it to form a judg- ment, whether we have really done justice to our purpose or not. Now the real problem of pure reason is contained in the question, How are synthetical judg- ments a priori possible ? That metaphysic has hitherto remained in so vacil- lating a state of ignorance and contradiction is entirely due to people not having thought sooner of this problem, or perhaps even of a distinction be- tween analytical and synthetical judgments. The solution of this problem, or a sufficient proof that a possibility which is to be explained does in reality not exist at all, is the question of life or death to metaphysic. David Hume, who among all philoso- phers approached nearest to that problem, though he was far from conceiving it with sufficient deflnite- ness and universality, confining his attention only to the sjTithetical proposition of the connection of an efiect with its causes (principium causahtatis), arrived at the conclusion that such a proposition a priori is entirely impossible. According to his conclu- sions, everything which we call metaphysic would turn out to be a mere delusion of reason, fancying that it knows by itself what in reality is only bor- rowed from experience, and has assumed by mere habit the appearance of necessity. If he had grasped our problem in all its universality, he would never have thought of an assertion which destroys all pure philosophy, because he would have perceived that, according to his argument, no pure mathematical science was possible either, on account of its certainly containing synthetical propositions a priori ; and from such an assertion his good sense would probably have saved him. 410 SUPPLEMENT VI. On the solution of our problem depends, at the same time, the possibility of the pure employment of reason, in establishing and carrying out all sciences which contain a theoretical knowledge a priori of objects, i.e. the answer to the questions How is pure mathematical science possible ? JSotv is pure natural science possible ? As these sciences really exist, it is quite proper to ask, Hoiv they are possible 1 for that they must be possible, is proved by their reality^. But as to metaphysic, the bad progress which it has hitherto made, and the impossibility of asserting of any of the metaphysical systems yet brought for- ward that it really exists, so far as its essential aim is concerned, must fill every one with doubts as to its possibility. Yet, in a certain sense, this Tcind of knowledge also must be looked upon as given, and though not as a science, yet as a natural disposition (metaphysica natu- ralis) metaphysic is real. For human reason, without being moved merely by the conceit of omniscience, ad- vances irresistibly, and urged on by its own need, to questions such as cannot be answered by any empirical employment of reason, or by principles thence derived, so that we may really say, that all men, as soon as their reason became ripe for speculation, have at all times possessed some kind of metaphysic, and will ' One might doubt this with regard to pure natural science ; but one has only to consider the different propositions which stand at the beginning of real (empirical) physical science, those, for example, relating to the permanence of the same quantity of matter to the vis inertiee, the equality of action and reaction, &c., in order to become convinced that they constitute a jihyscia pura, or ratio- nalis, which well deserves to stand by itself as an independent science, in its whole extent, whether narrow or wide. SUPPLEMENT VI. 41I always continue to possess it. And now it will also have to answer the question, How is metaphysic possible, as a natural disposition f that is, how does the nature of universal human reason give rise to questions which pure reason pro- poses to itself, and which it is urged on by its own need to answer as well as it can 1 As, however, all attempts which have hitherto been made at answering these natural questions (for in- stance, whether the world has a beginning, or exists from all eternity), have always led to inevitable con- tradictions, we cannot rest satisfied with the mere natural disposition to metaphysic, that is, with the pure faculty of reason itself, from which some kind of metaphysic (whatever it may be) always arises ; but it must be possible to arrive with it at some cer- tainty as to our either knowing or not knowing its objects ; that is, we must either decide that we can judge of the objects of these questions, and of the power or want of power of reason, in deciding any- thing upon them, — therefore that we can either enlarge our pure reason with certainty, or that we have to impose on it fixed and firm limits. This last question, which arises out of the former more general problem, would properly assume this form. How is metaphysic possible, as a science ? The critique of reason leads, therefore, necessarily, to true science, while its dogmatical use, without criticism, lands us in groundless assertions, to which others, equally specious, can always be opposed, that is, in scepticism. Nor need this science be very formidable by its great prolixity, for it has not to deal with the objects of reason, the variety of which is infinite, but with reason only, and with problems, suggested by reason 412 SUPPLEMENT VI. and placed before it, not by tbe nature of things, Avhich are different from it, but by its own nature ; so that, if reason has only first completely understood its own power, with reference to objects given to it in experience, it will have no difficulty in determining comjoletely and safely the extent and limits of its attempted application beyond the limits of all experience. We may and mu.st therefore regard all attempts which have hitherto been made at building up a metaphysic dogmatically, as non-avenii. For the mere analysis of the concepts that dwell in our reason a priori, which has been attempted in one or other of those metaphysical systems, is by no means the aim, but only a preparation for true metaphysic, namely, the answer to the question, how we can enlarge our knowledge a])riori synthetically; nay, it is utterly useless for that purpose, because it only shows what is contained in those concepts, but not by what process a j^riori we arrive at them, in order thus to determine the validity of their employ- ment with reference to all objects of knowledge in general. Nor does it require miich self-denial to give up these pretensions, considering that the unde- niable and, in the dogmatic procedure, inevitable con- tradictions of reason with itself, have long deprived every system of metaphysic of all authority. More firmness will be required in order not to be deterred by difiiculties from within and resistance from without, from trying to advance a science, indispensable to human reason, (a science of which we may lop off every branch, but will never be able to destroy the root,) by a treatment entirely opposed to all former treatments, which promises, at last, to ensure the suc- cessful and fruitful growth of metaphysical science. SUPPLEMENT YII. [Seevol.iLp.n] Still less ought we to expect here a criticism on the books and systems treating of pm-e reason, but only on the faculty of pure reason itself. It is only if we are in possession of this, that we possess a safe criterion for estimating the philosophical value of old and new works on this subject. Otherwise, an un- qualified historian and judge does nothing but criticise the groundless assertions of others by means of his own, which are equally groundless. SUPPLEMENT YIII. [see voi. ii. p. 23] 4. Space is represented as an infinite given quan- tity. Now it is quite true that every concept is to be thought as a representation, which is contained in an infinite number of different possible representations (as their common characteristic), and therefore com- prehends them : but no concept, as such, can be thought, as if it contained in itself an infinite number of representations. Nevertheless, space is so thought, (for all parts of space exist simultaneously ad infini- tum). Consequently, the original representation of space is an intuition a priori, and not a concept. §3. Transcendental Exposition of the concept of space. I understand by transcendental exposition {Eror- terung), the explanation of a concept, as of a principle by which the possibility of other synthetical kinds of knowledge a priori can be tmderstood. For this purpose it is necessary, i . That such kinds of know- ledge really do flow from the given concept. 2. That they are possible only under the presupposition of a given mode of explanation of such concept. G-eometry is a science which determines the pro- perties of space synthetically, and yet a priori. What then must be the representation of space, to render such a knowledge of it possible 1 It must be origi- nally intuitive ; for it is impossible from a mere concept to deduce propositions which go beyond that SUPPLEMENT VIII. 415 concept, as we do in geometry (Introduction V. See Supp. VI). That intuition, however, must be a priori, that is, it must exist within us before any perception of the object, and must therefore be pure, not empi- rical intuition. For all geometrical propositions are apodictic, that is, connected with the consciousness of their necessity, as for instance the proposition, that space has only three dimensions ; and such proposi- tions cannot be empirical judgments, nor conclusions from them (Introduction II. See Suppl. IV. 11). How then can an external intuition dwell in the mind anterior to the objects themselves, and in which the concept of objects can be determined a priori % Evidently not otherwise than so far as it has its seat in the subject only, as the formal condition' under which the subject is affected by the objects, in receiv- ing an immediate representation, that is, intuition of them ; therefore as a form of the external sense in general. It is therefore by our explanation only that the possibility oi geometry as a synthetical science a priori becomes intelligible. Every other explanation, which fails to account for this possibihty, can best be dis- tinguished from our own by that criterion, although it may seem to have some similarity with it. SUPPLEMENT IX. [see voi. n. p. 25] With the exception of space there is no other sub- jective representation, referring to something external, that could be called a jwiori objective. For from none of them can we derive synthetical propositions a jpriori, as \fQ can from the intuition in space ^. 3. (See Suppl. VIII). Strictly speaking, therefore, they can claim no ideality at all, though they agree with the representation of space in this, that they belong only to the subjective nature of sensibility, for instance, of sight, of hearing, and feeling, through the sensations of colours, sounds, and heat. All these, however, being sensations only, and not intuitions, do not help us by themselves to know any object, least of all a priori. SUPPLEMENT X. [see voi. u, p. 28] §5. Transcendental Exposition of the concept of time. I CAN here refer to No. iii. p. 2 7, where, for the sake of brevity, I have placed what is properly transcen- dental under the head of metaphysical exposition. Here I only add that the concept of change, and with it the concept of motion (as change of place), is possible only through and in the representation of time ; and that, if this representation were not intuitive (inter- nal) a priori, no concept, whatever it be, could make us understand the possibility of a change, that is, of a connection of contradictorily opposed predicates (for instance, the being and not-being of one and the same thing in one and the same place) in one and the same object. It is only in time that both con- tradictorily opposed determinations can be met with in the same object, that is, one after the other. Our concept of time, therefore, exhibits the possibility of as many synthetical cognitions a priori as are found in the general doctrine of motion, which is very rich in them. VOL. I. E e SUPPLEMENT XL [Seevol.ii,p.43] II. As a confirmation of this theory of the ideahty both of the external and of the internal sense, and therefore of aU objects of the senses as mere pheno- mena, we may particularly remark, that everything in our knowledge which belongs to intuition (exclud- ing therefore the feelings of pain and pleasure, and the will, which are no knowledge at all), contains nothing but mere relations, namely, of the places in an intuition (extension), change of places (motion), and laws, according to which that change is deter- mined (moving forces). Nothing is told us thereby as to what is present in the place, or what, besides the change of place, is active in the things. A thing by itself however cannot be known by mere relations, and we may, therefore, fairly conclude that, as the external sense gives us nothing but representations of relations, that sense can contain in its representa- tion only the relation of an object to the subject, and not what is inside the object by itself. The same applies to internal intuition. Not only do the repre- sentations of the external senses constitute its proper material with which we fill our mind, but time, in which these representations are placed, and which precedes even our consciousness of them in experience, nay, forms the formal condition of the manner in which we place them in the mind, contains itself relations of succession, co-existence, and that which must be co-existent with succession, namely, the per- manent. Now that which, as a representation, can SUPPLEMENT XI, 4I9 precede every act of thinking something, is the intui- tion : and, if it contains nothing but relations, then ■the form of intuition. As this represents nothing except what is being placed in the mind, it can itself be the manner only in which the mind, through its own activity, that is, by this placing of its representa- tion, is affected by itself, in other words, an internal sense with respect to its form. Whatever is repre- sented by a sense is so far always phenomenal, and we should therefore have either to admit no internal sense at all, or the subject, which is its object, could be represented by it as phenomenal only, and not, as it might judge of itself, if its intuition were spon- taneous only, that is, if it were intellectual. The difficulty here lies wholly in this, how a subject can have an internal intuition of itself: but this difficulty is common to every theory. The consciousness of self (apperception) is the simple representation of the ego, and if by it alone all the manifold (representa- tions) in the subject were given spontaneously, the inner intuition would be intellectual. In man this consciousness requires internal perception of the manifold, which is previously given in the subject, and the manner in which this is given in the mind without spontaneity, must, on account of this dif- ference, be called sensibility. If the faculty of self- consciousness is to seek for, that is, to apprehend, what lies in the mind, it must affect it, and can thus only produce an intuition of self. The form of this, which lay antecedently in the mind, determines the manner in which the manifold exists together in the mind, namely, in the representation of time. The intuition of self, therefore, is not, as if it could repre- sent itself immediately and as spontaneously and in- dependently active, but according to the manner in E e 2 420 SUPPLEMENT XI. which it is internally affected, consequently as it appears to itself, not as it is. III. If I say that the intuition of external objects and the self-intuition of the mind, represent both (viz. the objects and the mind) in space and time, as they affect our senses, that is, as they appear, I do not mean, that these objects are mere illusion. For the objects, as phenomena, nay, even the properties which we as- cribe to them, are always looked upon as something really given : and all we do is, that, as their quality depends only on the manner of intuition on the part of the subject in relation to a given object, we distinguish the object, as phenomenon, from itself, as an object by itself. Thus, if I assert that the quality of space and time, according to which, as a condition of their exist- ence, I accept both external objects and my own soul, Ues in my manner of intuition and not in these objects by themselves, I do not mean to say that bodies seem only to exist outside me, or that my soul seems only to be given in my self-consciousness. It would be my own fault, if I changed that, which I ought to count as phenomenal, into mere illusion ^. ^ Phenomenal predicates can be attributed to the object in its relation to our sense : as for instance to the rose its red colour, and its scent. But what is merely phenomenal can never be attributed to an object as a predicate, for the simple reason that the phenomenal ijttributes to the object by itself something which belongs to it only in its relation to the senses, or to a subject in general : as for instance the two handles, which were formerly attributed to Saturn. That which is never to be found in the object itself, but always in its relation to a subject, and is inseparable from its representation by a subject, is phenomenal, and the predicates of space and time are therefore rightly attributed to objects of the senses, as such. In this there is no illusion. If, on the contrary, I were to attribute to the rose 6y itself, redness, handles to Saturn, and extension to all external objects, without restricting my judgment to the rela- tion of these objects to a subject, we should have illusion. SUPPLEMENT XI. 42 1 This cannot happen, however, according to onr principle of the ideality of all sensuous intuitions ; on the contrary, it is only when we attribute objective reality to those forms of intuition, that everything is changed inevitably into mere illusion. For if we take space and time as properties that ought to exist in things by themselves, in order to make them possible, and then survey the absurdities in which we should be involved in having to admit that two infinite things, which are not substances, nor something inherent in substances, but nevertheless must be something existing, nay, the necessary condition of the existence of all things, would remain, even if all existing things were removed, we really cannot blame the good Bishop Berkeley for degrading bodies to mere illusion. Nay, it would follow that even our own existence, which would thus be made dependent on the independent reality of such a non-entity as time, must become a mere illusion, an absurdity which hitherto no one has been guilty of. IV. In natural theology, where we think of an object which not only can never be an object of intuition to us, but which even to itself can never be an object of sensuous intuition, great care is taken to remove all conditions of space and time from its intuition (for all its knowledge must be intuitive, and not thought, which always involves limitation). But how are we justified in doing this, when we have first made space and time forms of things by themselves, such as would remain as conditions of the existence of things a priori, even if the things them- selves had been removed 1 If conditions of all exist- ence, they would also be conditions of the existence of God. If we do not wish to change space and time into objective forms of all things, nothing remains but 42 2 SUPPLEMENT XI. to accept them as subjective forms of our external as well as internal intuition, which is called sensuous, for the very reason that it is not originally spon- taneous, that is such, that it could itself give us the existence of the objects of intuition (such an in- tuition, so far as we can understand, can belong to the First Being only), but dependent on the exist- ence of objects, and therefore possible only, if the faculty of representation in the subject is affected by them. It is not necessary, moreover, that we should limit this intuition in space and time to the sensibility of man ; it is quite possible that all finite thinking beings must necessarily agree with us on this point (though we cannot decide this). On account of this universal character, however, it does not cease to be sensibility, for it always is, and remains derivative (intuitus derivativus), not original (intuitus origina- rius), and therefore not intellectual intuition. For the reason mentioned before, the latter intuition seems only to belong to the First Being, and never to one which is dependent, both in its existence and its intmtion, (which intuition determines its existence with reference to given objects). This latter remark, however, must only be taken as an illustration of our aesthetic theory, and not as a proof. Conclusion of the Transcendental Esthetic. Here, then, we have one of the reqiiisites for the solution of the general problem of transcendental philosophy, How are synthetical propositions a priori possible ? namely, pure intuitions u priori, space and time. In them we find, if in a judgment a priori we want to go beyond a given concept, that which SUPPLEMENT XI. 423 can be discovered a priori, not in the concept, but in the intuition corresponding to it, and can be con- nected with it synthetically. For this very reason, however, such judgments can never go beyond the objects of the senses, but are valid only for objects of possible experience. SUPPLEMENT XII. [See vol. ii, p. 74] ^11. This table of categories suggests some interesting considerations, which possibly may have important consequences with regard to the scientific form of all knowledge of reason. For it is clear that such a table will be extremely useful, nay, indispensable, in the theoretical part of philosophy, in order to trace the comflete plan of a ivliole science, so far as it rests on concepts a priori, and to divide it mathematically according to fixed principles, because that table con- tains all elementary concepts of the understanding in their completeness, nay, even the form of a system of them in the human understanding, and indicates therefore all the momenta of a projected speculative science, nay, even their order. Of this I have given an example elsewhere ^. Here follow some of the considerations. The first is, that this table, which contains four classes of the concepts of the understanding, may, in the first instance, be divided into two sections, the former of which refers to objects of intuition (pure, as well as empirical), the latter to the exist- ence of those objects (either in their relation to each other, or to the understanding). The first section I shall call that of the mathe- matical, the second, that of the dynamical categories. The first section has no correlates, which are met with in the second section only. Must not this ' Metaphysical Elements of Natural Science. SUPPLEMENT XII. 425 difference have some ground in the nature of tlie understanding 1 Our second remarli is, that in every class there is the same number of categories, namely three, which again makes us ponder, because generally all division a priori by means of concepts must be dichotomy. It should be remarked also, that the third category always arises from the combination of the second with the first. Thus totality is nothing but plurality considered as unity ; limitation nothing but reahty connected with negation ; community is the causality of a substance as determining another reciprocally ; lastly, necessity, the existence which is given by possibility itself. It must not be sup- posed, however, that therefore the third category is only a derivative, and not a primary concept of the pure understanding. For the joining of the first and second concepts, in order to produce the third, re- quires an independent act of the understanding, which is not identical with the act that produces the first and second concepts. Thus the concept of a number (which belongs to the category of totality), is not always possible when we have the concepts of plurality and unity (for instance, in the concept of the infinite) ; nor can we understand by simply com- bining the concept of a cause and that of a substance, the influence, that is, how a substance can become the cause of something in another substance. This shows that a separate act of the understanding is here required, and the same applies to all the rest. Third observation. With regard to one category, namely, that of community, which is found in the third class, its accordance with the form of a dis- junctive judgment, which corresponds to it in the 426 SUPPLEMENT XII. table of logical functions, is not so evident as else- where. In order to become quite certain of that accord- ance, we must remark that in all disjunctive judg- ments their sphere (that is, all that is contained in them) is represented as a whole, divided into parts (the subordinate concepts), and that, as one of them cannot be contained under the other, they are con- ceived as co-ordinate, not as subordinate, determining each other, not in one direction only, as in a series, but reciprocally, as in an aggregate (if one member of the division is given, all the rest are excluded, and vice versa). A similar connection is conceived in a whole of things, in which one, aa effect, is not subordinated to another as the cause of its existence, but is co- ordinated with it, simultaneously and reciprocally, as cause of the determination of the other (as, for instance, in a body of which the parts reciprocally attract and repel each other). This is a kind of con- nection totally different from that which exists in a mere relation of cause to effect (of ground to con- sequence), for here the consequence does not recipro- cally determine the ground again, nor (as in the case of the Creator and the creation) constitute with it a whole. The process of the understanding, in repre- senting to itself the sphere of a divided concept, is the same as that by which it thinks a thing as divisible : and in the same manner in which, in the former, the members of a division exclude each other, and are yet connected in one sphere, the understand- ing represents to itself the parts of the latter as existing (as substances), each independent of the rest, and yet united in a whole. SUPPLEMENT XII. 427 § 12. In the transcendental pliilosophy of the ancients there is another chapter containing concepts of the understanding which, though they are not counted among the categories, are yet considered by them as concepts a friori of objects. If so, they would increase the number of the categories, which cannot be. They are set forth in the famous proposition of the Schoolmen, ' quodlibet ens est imum, verum, bonum.' Now although the inferences to be drawn from this principle (yielding nothing but tautological propositions) were very meagre, so that modern metaphysicians mention it almost by courtesy only, a thought which has maintained itself so long, how- ever empty it may seem, deserves an investigation with regard to its origin, nay, leads us to suspect that it may have its foundation in some rule of the understanding which, as often happens, has only been wrongly interpreted. What are supposed to be trans- cendental predicates of things, are nothing but logical requirements and criteria of all knowledge of things in general, whereby that knowledge is founded on the categories of quantity, namely, unity, plurality, and totality. Only, instead of taking them as materially belonging to the possibility of things by themselves, they (the predicates, or rather those who employed them) used them, in fact, m their formal meaning only, as forming a logical requisite for every kind of knowledge, and yet incautiously made these criteria of thought to be properties of the things by them- selves. In every cognition of an object there is unity of concept, which may be called qualitative unity, so far as we think by it only the unity in the comprehension of the manifold material of our know- 428 SUPPLEMENT XII. ledge : as, for instance, the unity of the subject in a play, or a speech, or a fable. Secondly, there is truth, in respect to the deductions from it. The more true deductions can be made from a given concept, the more criteria are there of its objective reality. This might be called the qualitative ^plurality of criteria, which belong to a concept as their common ground (but are not conceived in it), as quantity. Thirdly, there is completeness, which consists in this, that the plurality together leads back to the unity of the concept, according completely with this and with no other concept, which may be called the qualitative completeness (totality). This shows that these logical criteria of the possibility of knowledge in general do nothing but change the three categories of quan- tity, in which the unity in the production of the quantum must throughout be taken as homogeneous, for the purpose of connecting heterogeneous elements of knowledge also in one consciousness, by means of the quality of the cognition as the principle of the connection. Thus the criterion of the possibility of a concept (but not of its object) is the definition of it, in which the unity of the concept, the truth of all that may be immediately deduced from it, and lastly, the comjpleteness of what has been deduced from it, supply all that is necessary for the constitution of the whole concept. In the same manner the criterion of an hypothesis consists, first, in the intelligibility of the ground which has been admitted for the sake of explanation, or of its unity (without any auxihary hypothesis) ; secondly, in the truth of the conse- quences to be deduced from it (their accordance with themselves and with experience) ; and lastly, in the completeness of the ground admitted for the explana- tion of these consequences, which point back to SUPPLEMENT XII. 429 neither more nor less than what was admitted in the hypothesis, and agree in giving us again, analytically a posteriori, what had been thought synthetically a priori. The concepts of unity, truth, and perfec- tion do not supplement the transcendental table of the categories, as if it were imperfect, but they serve only, after the relation of these concepts to their objects has been entirely set aside, to bring their employment under general logical rules, for the agreement of knowledge with itself. SUPPLEMENT XIII. [see voi. h, p. 84] Locke, for want of this reflection, and because he met with pure concepts of the understanding in expe- rience, derived tliem also from experience, and yet acted so inconsistently that he attempted to use them for knowledge which far exceeds all Hmits of experi- ence. David Hume saw that, in order to be able to do this, these concepts ought to have their origin a priori ; but as he could not explain how it was possible that the understanding should be constrained to think concepts, which by themselves are not united in the understanding, as necessarily united in the object, and never thought that possibly the under- standing might itself, through these concepts, be the author of that experience in which its objects are found, he was driven by necessity to derive them from experience (namely, from a subjective necessity, pro- duced by frequent association in experience, which at last is wrongly supposed to be objective, that is, from habit). He acted, however, very consistently, by declaring it to be impossible to go with these con- cepts, and with the principles arising from them, beyond the limits of experience. This empirical deduction, which was adopted by both philosophers, cannot be reconciled with the reality of our scientific knowledge a priori, namely, pure mathematics and general natural science, and is therefore refuted by facts. The former of these two celebrated men opened a wide door to fantastic extravagance, because reason, if it has once established such pretensions, SUPPLEMENT XIII. 43 1 can no longer be checked by vague praises of moder- ation ; the other, thinking that he had once discovered so general an illusion of our faculty of knowledge, which had formerly been accepted as reason, gave himself over entirely to scepticism. We now intend to make the experiment whether it is not possible to conduct reason safely between these two rocks, to assign to her definite limits, and yet to keep open for her the proper field for all her activities 1 I shall merely premise an explanation of what I mean by the categories. They are concepts of an object in general by which its intuition is defined through one of the logical functions in judgments. Thus the function of the categorical judgment was that of the relation of the subject to the predicate ; for instance, all bodies are divisible. Here, however, with reference to the pure logical function of the understanding, it remained undetermined to which of the two concepts the function of the subject, or the predicate, was to be assigned. For we could also say, some divisible is body. But by bringing the concept of body under the category of substance, it is deter- mined that its empirical intuition in experience must always be considered as subject and never as predi- cate only. The same applies to all other categories. SUPPLEMENT XIY. [see voi. ii, p. 84] OF THE DEDUCTION OF THE PURE CONCEPTS OP THE UNDERSTANDING. Second Section. Transcendental deduction of the pure Concej^ts of the Understanding. f 15. Of the possibility of comiecting (conjunctio) in general. The manifold of representations may be given in an intuition wHch is purely sensuous, that is, nothing but receptivity, and the form of that intuition may lie a priori in our faculty of representation, without being anything but the manner in which a subject is affected. But the connection (conjunctio) of anything manifold can never enter into us through the senses, and cannot be contained, therefore, already in the pure form of sensuous intuition, for it is a spontaneous act of the power of representation ; and as, in order to dis- tinguish this from sensibility, we must call it under- standing, we see that all connecting, whether we are conscious of it or not, and whether we connect the manifold of intuition or several concepts together,^ and again, whether that intuition be sensuous or not sen- suous, is an act of the understanding. " This act we shall call by the general name of synthesis, in order to show that we cannot represent to ourselves anything as connected in the object, without having previously SUPPLEMENT XIV. 433 connected it ourselves, and that of all representations connection is the only one which cannot be given through the objects, but must be carried out by the ' subject itself, because it is an act of its spontaneity. It can be easily perceived that this act must be ori- ginally one and the same for every kind of connection, and that its dissolution, that is, the analysis, which seems to be its opposite, does always presuppose it. For where the understanding has not previously con- nected, there is nothing for it to disconnect, because, as connected, it could only be given by the under- standing through the faculty of representation. But the concept of connection includes, besides the concept of the manifold and the synthesis of it, the concept of the unity of the manifold also. Connection is representation of the synthetical unity of the mani- foldi. The representation of that unity cannot therefore be the result of the connection ; on the contrary, the concept of the connection becomes first possible by the representation of unity being added to the repre- sentation of the manifold. And this unity, which precedes a priori all concepts of connection, must not be mistaken for that category of unity of which we spoke on p. 68; for all categories depend on logical functions in judgments, and in these we have already connection, and therefore unity of given concepts. The category, therefore, presupposes connection, and we must consequently look still higher for this unity ^ "Whether the representations themselves are identical, and whether therefore one can be thought analytically by the other, is a matter of no consequence here. The consciousness of the one has always to be distinguished from the consciousness of the other, so far as the manifold is concerned ; and everything here depends on the synthesis only of this (possible) consciousness. VOL. I. F f 434 SUPPLEMENT XIV. as qiialitative (see Suppl. XIT. § 1 2), in that, namely, whicli itself contains the ground for the unity of different concepts in judgment, and therefore of the very possibility of the understanding in its logical employment. § 16. T]ie original synthetical unity of Apperception. It must be possible that the I think should accom- pany all my representations : for otherwise something would be represented within me that could not be thought, in other words, the representation would either be impossible or nothing, at least so far as I am concerned. That representation which ca.n be given before all thought, is called intuition, and all the manifold of intuition has therefore a necessary relation to the I think in the same subject in which that manifold of intuition is found. That representation, however (intuition), is an act of spontaneity, that is, it cannot be considered as belonging to sensibihty. I call it fure apperception, in order to distinguish it from empirical apperception, or original apperception also, because it is that self-consciousness which by producing the representation, I think, which must accompany all others, and is one and the same in every act of consciousness, cannot itself be accom- panied by any other. I also call the unity of it the transcendental unity of self-consciousness, in order to indicate that it contains the possibiHty of knowledge a priori. For the manifold representations in any given intuition would not all be in my representa- tions, if they did not all belong to one self-conscious- ness. What I mean is that, as my representations (even though I am not conscious of them as such), they must be in accordance with that condition, under SUPPLEMENT XIV. 435 whicli alone they can stand together in one common self-consciousness, because otherwise they would not all belong to me. Much may be deduced from this original connection. Thus the unbroken identity of apperception of the manifold that is given in intuition contains a syn- thesis of representations, and is possible only through the consciousness of that synthesis. The empirical consciousness, which accompanies various representa- tions, is itself various and disunited, and without reference to the identity of the subject. Such a rela- tion takes place, not by my simply accompanying every relation with consciousness, but by my adding one to the other and being conscious of that act of adding, that is, of that synthesis. Only because I am able to connect the manifold of given representations in one consciousness, is it possible for me to represent to myself the identity of the consciousness in these representations, that is, only under the supposition of some synthetical unity of apperception does the ana- lytical imity of apperception become possible ^. ^ Tliis analytical unity of consciousness belongs to all general concepts, as such. If, for instance, I think red in general, I re- present to myself a property, which (as a characteristic mark) may be found in something, or can be connected with other repre- sentations ; that is to say, only under a presupposed possible synthetical unity can I represent to myself the analytical. A re- presentation which is to be thought as common to different repre- sentations, is looked upon as belonging to such as possess, besides it, something different. It must therefore have been thought in synthetical unity with other (though only possible) representations, before I can think in it ihat analytical unity of consciousness which makes it a conceptus communis. The synthetical unity of apper- ception is, therefore, the highest point with which all employment of the understanding, and even the whole of logic, and afterwards the whole of transcendental philosophy, must be connected; ay, that faculty is the understanding itself. Ff 2 436 SUPPLEMENT XIV. The thought that the representations given in intu- ition belong all of them to me, is therefore the same as that I connect them in one self-consciousness, or am able at least to do so ; and though this is not yet the consciousness of the synthesis of representations, it nevertheless presupposes the possibility of the latter. In other words, it is only because I am able to comprehend the manifold of representations in one consciousness, that I call them altogether my repre- sentations, for otherwise, I should have as manifold and various a self as I have representations of which I am conscious. The synthetical unity of the mani- fold of intuitions as given a priori is therefore the ground also of the identity of tha,t apperception itself which precedes a priori all definite thought. Con- nection, however, does never lie in the objects, and cannot be borrowed from them by perception, and thus be taken into the understanding, but it is always an act of the understanding, which itself is nothing but a faculty of connecting a priori, and of bringing the manifold of given representations under the unity of apperception, which is, in fact, the highest principle of all human knowledge. It is true, no doubt, that this principle of the necessary unity of apperception is itself identical, and therefore an analytical proposition ; but it shows, nevertheless, the necessity of a synthesis of the mani- fold which is given in intuition, and without which it would be impossible to think the unbroken identity of self-consciousness. For through the Ego, as a simple representation, nothing manifold is given ; in the intuition, which is different from that, it can be giveu only, and then, by connection, be thought in one con- sciousness. An understanding in which, by its self- consciousness, all the manifold would be given at the SUPPLEMENT XIV. 437 same time, would possess intuition ; our understand- ing can do nothing but think, and must seek for its intuition in the senses. I am conscious, therefore, of the identical self with respect to the manifold of the representations, which are given to me in an in- tuition, because I call them, altogether, my repre- sentations, as constituting one. This means, that I am conscious of a necessary synthesis of them a priori, which is called the original synthetical unity of ap- perception under which all representations given to me must stand, but have to be brought there, first, by means of a synthesis. § 17- The principle of tJie synthetical unity of Apperception is the highest principle of all employment of the Understanding. The highest principle of the possibility of all in- tuition, in relation to sensibility, was, according to the transcendental Esthetic, that all the manifold in it should be subject to the formal conditions of space and time. The highest principle of the same possi- bility in relation to the understanding is, that all the manifold in intuition must be subject to the con- ditions of the original synthetical unity of appei- ception ^. ' Space and time, and all portions thereof, are intuitions, and consequently single representations with the manifold for their content. (Se« the Transcendental Esthetic.) They are not, there- fore, mere concepts, through which the same consciousness, as existing in many representations, but through which many repre- sentations, as contained in one, and in its consciousness (therefore as compounded) are brought to us ; thus representing the unity of 438 SUPPLEMENT XIV. All the manifold representations of intuition, so far as tliey are give^i us, are subject to the former, so far as they must admit of being connected in one consciousness, to the latter ; and withotit that nothing can be thought or known, because the given repre- sentations would not share the act of apperception (I think) in common, and cou^ld not be comprehended in one self-consciousness. The understanding in its most general sense is the faculty of cognitions. These consist in a definite relation of given representations to an object ; and an object is that in the concept of which the manifold of a given intuition is connected. All such connection of representations requires of course the unity of the consciousness in the synthesis : consequently, the unity of consciousness is that which alone constitutes the relation of representations to an object, that is, their objective validity, and consequently their be- coming cognitions, so that the very possibility of the understanding depends on it. The first pure cognition of the understanding, therefore, on which all the rest of its employment is founded, and which at the same time is entirely in- dependent of all conditions of sensiious intuition, is this very principle of the original synthetical unity of apperception. Space, the mere form of external sensuous intuition, is not yet cognition : it only sup- plies the manifold of intuition a priori for a possible cognition. In order to know anything in space, for instance, a line, I must draio it, and produce syn- thetically a certain connection of the manifold that is given, so that the unity of that act is at the same time the unity of the consciousness (in the concept coDsciousness as synthetical, but yet as primitive. This character of singleness in them is practically of great importance (see § 2 5). SUPPLEMENT XIV. 439 of a line), and is thus only known, for the first time, as an object (a determinate space). The synthetical unity of consciousness is, therefore, an objective con- dition of all knowledge; a condition, not necessary for myself only, in order to know an object, but one to which each intuition must be subject, in order to become an object for me, because the manifold could not become connected in one consciousness in any other way, and without such a synthesis. No doubt, that proposition, as I said before, is itself analytical, though it makes synthetical unity a condition of all thought, for it really says no more than that all my representations in any given in- tuition must be subject to the condition under which alone I can ascribe them, as my representations, to the identical self, and therefore comprehend them, as synthetically connected, in one apperception through the general expression, I thinh. And yet this need not be a principle for every possible understanding, but only for that which gives nothing manifold through its pure apperception in the representation, I am. An understanding which through its self-consciousness could give the mani- fold of intuition, and by whose representation the objects of that representation should at the same time exist, would not require a special act of the synthesis of the manifold for the unity of its con- sciousness, while the human understanding, which possesses the power of thought only, but not of in- tuition, requires such an act. To the human under- standing that first principle is so indispensable that it really cannot form the least concept of any other possible understanding, whether it be intuitive by itself, or possessed of a sensuous intuition, different from that in space and time. 440 SUPPLEMENT XIV. § i8. What is the objective unity of Self-consciousness f The transcendental tmity of apperception connects all the manifold given in an intuition into a concept of an object. It is therefore called objective, and must be distinguished from the subjective unity of consciousness, which is a form of the internal sense, by which the manifold of intuition is empirically given, to be thus connected. Whether I can be- come empirically conscious of the manifold, as either simultaneous or successive, depends on circumstances, or empirical conditions. The empirical unity of con- sciousness, therefore, through the association of repre- sentations, is itself phenomenal and wholly contin- gent, while the pure form of intuition in time, merely as general intuition containing the manifold that is given, is subject to the original unity of the con- sciousness, through the necessary relation only of the manifold of intuition to the one, I think, — that is, through the pure synthesis of the understanding, which forms the a priori ground of the empirical synthesis. That unity alone is, therefore, valid ob- jectively ; the empirical unity of apperception, which we do not consider here, and which is only derived from the former, under given conditions in concrete, has subjective validity only. One man connects the representation of a word with one thing, another with another, and the unity of consciousness, with regard to what is empirical, is not necessary nor uni- versally valid with reference to that which is given. SUPPLEMENT XIV. 44 1 § 19- The logical form of all Judgments consists in the ob- jective unity of Afjiercejption of the concepts contained therein. I could never feel satisfied with the definition of a judgment in general, given by our logicians, who say that it is the representation of a relation between two concepts. Without disputing with them in this place as to the defect of that explanation, which may possibly apply to categorical, but not to hypothetical and disjunctive judgments (the latter containing, not a relation of concepts, but of judg- ments themselves), — though many tedious conse- quences have arisen from this mistake of logicians, — I must at least make this observation, that we are not told in what that relation consists ^. But, if I examine more closely the relation of cog- nitions in every judgment, and distinguish it, as belonging to the understanding, from the relation according to the rules of reproductive imagination (which has subjective validity only), I find that a judgment is nothing but the mode of bringing given cognitions into the objective unity of apperception. This is what is intended by the copula is, which is meant to distinguish the objective unity of given ' The lengtliy doctrine of the four syllogistic figures concerns categorical syllogisms only, and though it is really nothing but a trick for obtaining the appearance of more modes of concluding than that of the first figui'e, by secretly introducing immediate conclusions (consequentise immediatee) among the premisses of a pure syllogism, this would hardly have secured its great success, had not its authors succeeded, at the same time, in establishing the exclusive authority of categorical judgments, as those to which all others must be referred. This, as we showed iu § 9, p. 62, is wrong. 442 SUPPLEMENT XIV. representations from the subjective. It indicates their relation to the original apperception, and their necessary unity, even though the judgment itself be empirical, and therefore contingent ; as, for instance, bodies are heavy. By this I do not mean to say tliat these representations belong necessarily to each other, in the empirical intuition, but that they belong to each other by means of the necessary unity of apperception in the synthesis of intuitions, that is, according to the principles of the objective deter- mination of all representations, so far as any cog- nition is to arise from them, these principles being aU derived from the principle of the transcendental unity of apperception. Thus, and thus alone, does the relation become a judgment, that is, a relation that is valid objectively, and can thus be kept sufficiently distinct from the relation of the same representations, if it has subjective validity only, for instance, according to the laws of association. In the latter case, I could only say, that if I carry a body I feel the pressure of its weight, but not, that it, the body, is heavy, which is meant to say that these two representations are connected together, in the object, whatever the state of the subject may be, and not only in a perception, however often it may be repeated. I 20. All sensuous Intuitions are subject to the categories as conditions under ivhicli alone their manifold con- tents can come together in one Consciousness. The manifold which is given us in a sensuous in- tuition is necessarily subject to the original unity of apperception, because by it alone the unity of intu- SUPPLEMENT XIV. 443 ition becomes possible {§ 7). That act of the under- standing, however, by which the manifold of given representations (whether intuitions or concepts) is brought under one apperception, is the logical func- tion of a judgment {§ 19). The manifold, therefore, so far as it is given in an empirical intuition, is determined with regard to one of the logical functions of judgment, whereby alone it can become consciousness. The categories, however, are nothing but these functions of judgment, so far as the mani- fold of a given intuition is determined with respect to them {§ 13, see p. 84). Therefore the manifold in any given intuition is naturally subject to the categories. f 21. Note. The manifold, contained in an intuition which I call my own, is represented through the synthesis of the understanding, as belonging to the necessary unity of self-consciousness, and this takes place through the category'. This category indicates, therefore, that the empirical consciousness of the manifold, given in any intuition, is subject to a pure self-consciousness a priori, in the same manner as the empirical intuition is subject to a pure sensuoiis intuition which likewise takes place a priori. In the above proposition a beginning is made of a . deduction of the pure concepts of the understanding. In this, as the categories arise in the understanding ' The proof of this rests on the represented unity of intuition, by which an object is given, and whicli always includes a synthesis of the manifold which is given for an intuition, and contains the relation of the latter to the unity of apperception. 444 SUPPLEMENT XIV. only, independent of all sensibility, I ought not yet to take any account of the manner in which the mani- fold is given for an empirical intuition, but attend exclusively to the unity which, by means of the cate- gory, enters into the intuition through the under- standing. In what follows {§ 26) we shall show, from the manner in which the empirical intuition is given in sensibility, that its unity is no other than that which is prescribed by the category, (according to § 20) to the manifold of any given intuition. Thus only, that is, by showing their validity a priori with respect to all objects of our senses, the purpose of our deduction will be fully attained. There is one thing, however, of which, in the above demonstration, I could not make abstraction : namely, that the manifold for an intuition must be given ante- cedently to the synthesis of the understanding, and in- dependently of it ; — how, remains uncertain. For if I were to imagine an understanding, itself intuitive (for instance, a divine understanding, which should not represent to itself given objects, but produce them at once by his representation) the categories would have no meaning with respect to such cognition. They are merely rules for an understanding whose whole power consists in thinking, that is, in the act of bringing the synthesis of the manifold, which is given to it m intuition from elsewhere, to the unity of ap- perception ; an undertaking which therefore knows nothing by itself, but connects only and arranges the material for cognition, that is, the intuition which must be given to it by the object. This peculiarity of our understanding of producing unity of apper- ception a priori by means of the categories only, and again by such and so many, cannot be further explained, any more than why we have these and no SUPPLEMENT XIV. 445 other functions of judgment, and why time and space are the only forms of a possible intuition for us. I 22. The category admits of no other employment for the cognition of Things, lut its aj)])lication to oljects of Experience. We have seen that to think an object is not the same as to know an object. In order to know an object, we must have the concept by which any object is thought (the category), and likewise the intuition by which it is given. If no corresponding intuition could be given to a concept, it would still be a thought, so far as its form is concerned : but it would be without an object, and no knowledge of anything would be possible by it, because, so far as I know, there would be nothing, and there could be nothing, to which my thought could be referred. Now the only possible intuition for us is sensuous (see Esthetic) ; the thought of any object, therefore, by means of a pure concept of the understanding, can with us become knowledge only, if it is referred to ob- jects of the senses. Sensuous intuition is either pure (space and time), or empirical, i.e. if it is an intui- tion of that which is represented immediately through sensation, as real in space and time. By means of pure intuition we can gain knowledge a priori of things as phenomena (in mathematics), but only so far as their form is concerned : but whether there are things which must be perceived, according to that form, remains unsettled. Mathematical concepts, by themselves, therefore, are not yet knowledge, except under the supposition that there are things which admit of being represented by us, according to the 446 SUPPLEMENT XIV. form of that pure sensuous intuition only. Conse- quently, as tilings in space and time are only given as perceptions (as representations accompanied by sen- sations), that is, through empirical representations, the pure concepts of the understanding, even if applied to intuitions a priori, as in mathematics, give us knowledge in so far only as these pure intuitions, and therefore through them the concepts of the understanding also, can be applied to empirical intui- tions. In the same manner the categories, by means of intuition, do not give us any knowledge of things, except under the supposition of their possible appli- cation to empirical intuition ; they serve, in short, for the possibility of empirical knoivledge only, which is called experience. From this it follows that the cate- gories admit of no other employment for the cogni- tion of things, except so far only as these are taken as objects of possible experience. I 23. The foregoing proposition is of the greatest impor- tance, for it determines the limits of the employment of the pure concepts of the understanding with reference to objects, in the same manner as the Tran- scendental ^Esthetic determined the limits of the employment of the pure form of our sensuous in- tuition. Space and time are conditions of the pos- sibility of how objects can be given to us, so far only as objects of the senses, therefore of experi- ence, are concerned. Beyond these limits they represent nothing, for they belong only to the senses, and have no reality beyond them. Pure concepts of the understanding are free from this hmitation, and extend to objects of intuition in general, whether that intuition be like our own or not, if only it is sensuous SUPPLEMENT XIV. 447 and not intellectual. This further extension, how- ever, of concepts beyond our sensuous intuition, is of no avail to us ; for they are in that case empty con- cepts of objects, and the concepts do not even enable us to say, whether such objects be possible or not. They are mere forms of thought, without objective reality: because we have no intuition at hand to which the synthetical unity of apperception, which alone is contained in the concepts, could be applied, so that they might determine an object. Nothing can give them sense and meaning, except our sensuous and empirical meaning. If, therefore, we assume an object of a non-sensuous intuition as given, we may, no doubt, determine it through all the predicates, which follow from the supposition that notJiing helonging to sensuous intui- tion belongs to it, that, therefore, it is not extended, or not in sj^ace, that its duration is not time, that no change (succession of determinations in time) is to be met in it, &c. But we can hardly call tliis knowledge, if we only indicate how the intuition of an object is not, without being able to say what is contained in it, for, in that case, I have not represented the possi- bility of an object, corresponding to my pure concept of the understanding, because I could give no intui- tion correspondmg to it, but could only say that our intuition did not apply to it. But what is the most important is this, that not even a single category could be applied to such a thing ; as for instance, the concept of substance, that is, of something that can exist as a subject only, but never as a mere predicate. I should not know, therefore, whether there could be anything corresponding to such a determination of thought, unless empirical intuition supplied the case for its apphcation. Of this more hereafter. 448 SUPPLEMENT XIV. § 24. Of the a'p^lication of the Categories to objects of the senses in general. The pure concepts of the understanding refer, through the understanding, to objects of intuition, whether it be our own, or any other, if only sensuous intuition, but they are, for that very reason, mere forms of thought, by which no definite object can be known. The synthesis, or connection of tlie manifold in them, referred only to the unity of apperception, and became thus the ground of the possibUity of knowledge a j)riori, so far as it rests on the under- standing, and is therefore not only transcendental, but also purely intellectual. As there exists in us a certain form of sensuous intuition a priori, which rests on the receptivity of the faculty of representa- tion (sensibility), the understanding, as spontaneity, is able to determine the internal sense through the manifold of given representations, according to the synthetical unity of apperception, and can thus think synthetical unity of the apperception of the manifold, in sensuous intuition a jyriori, as the condition to which all objects of our (human) intuition must necessarily be subject. Thus the categories, though pure forms of thought, receive objective reality, that is, application to objects which can be given to us in intuition, but as phenomena only; for it is with reference to them alone that we are capable of intuition a priori. This synthesis of the manifold of sensuous intuition, which is possible and necessary a priori, may be called figurative (synthesis speciosa), in order to dis- tinguish it from that which is thought in the mere category, with reference to the manifold of an intuition SUPPLEMENT XIV. 449 in general, and is called intellectual synthesis (syn- thesis intellectualis). Both are transcendental, not only because they themselves are carried out a priori, but because they establish also the possibility of other knowledge a priori. But this figurative synthesis, if it refers to the original synthetical unity of apperception only, that is, to that transcendental unity which is thought in the categories, must be called the transcendental synthesis of the faculty of imagination, in order thus to distinguish it from the purely intellectual synthesis. Imagination is the faculty of representing an object even without its presence in intuition. As all our intuition is sensxious, the faculty of imagination belongs, on account of the subjective condition under which alone it can give a corresponding intuition to the concepts of the understanding, to our sensibility. As however its synthesis is an act of spontaneity, determining, and not, like the senses, determinable only, and therefore able to determine a priori the senses, so far as their form is concerned, according to the unity of apperception, the faculty of imagination is, so far, a faculty of determining our sensibility a priori, so that the synthesis of the intuitions, ac- cording to the categories, must be the transcendental synthesis of the faculty of imagination. This is an effect, produced by the understanding on our sensi- bility, and the first application of it (and at the same time the ground of all others) to objects of an intui- tion possible to us. As figurative, it is distinguished from the intellectual synthesis, which takes place by the understanding only, without the aid of the faculty of imagination. In so far as imagination is sponta- neity, I call it occasionally productive imagination : distinguishing it from the reproductive, which in its VOL. I. G g 450 SUPPLEMENT XIV. synthesis is subject to empirical laws only, namely those of association, and which is of no help for the explanation of the possibility of knowledge a priori, belonging, therefore, to psychology, and not to transcendental philosophy. This is the proper place for trying to account for the paradox, which must have struck everybody in our exposition of the form of the internal sense (§ 6, see p. 28) ; namely, how that sense represents to the consciousness even ourselves, not as we are by ourselves, but as we appear to ourselves, because we perceive ourselves only as we are affected in- ternally. This seems to be contradictory, because we should thus be in a passive relation to ourselves ; and for this reason the founders of the systems of psychology have preferred to represent the internal sense as identical with the faculty of apperception, while we have carefully distinguished the two. What determines the internal sense is the under- standing, and its original power of connecting the manifold of intuition, that is, of bringing it under one apperception, this being the very ground of the possibility of the understanding. As in us men the understanding is not itself an intuitive faculty, and could not, even if intuitions were given in our sensi- bility, take them into itself, in order to connect, as it were, the manifold of its own intuition? the syn- thesis of the understanding, if considered by itself alone, is nothing but the unity of action, of which it is conscious without sensibility also, but through which the understanding is able to determine that sensibility mternally, with respect to the manifold which may be given to it according to the form of SUPPLEMENT XIV. 45 1 its intuition. The understanding, therefore, exercises its activity, under the name of a transcendental syn- thesis of the faculty of imagination, on the passive subject to which it belongs as a faculty, and we are right in saying that the internal sense is affected by that activity. The apperception with its synthetical unity is so far from being identical with the internal sense, that, as the source of aU synthesis, it rather applies, under the name of the categories, to the manifold of intuitions in general, that is, to objects before all sensuous intuition ; whUe the internal seuse, on the contrary, contains the mere form of intuition, but without any connection of the manifold in it, and therefore, as yet, no definite intuition, which becomes possible only through the consciousness of the determination of the internal sense by the transcendental act of the faculty of imagination (the synthetical influence of the understanding on the internal sense) which I have called the figurative synthesis. This we can always perceive in ourselves. We cannot think a line without drawing it in thought; we cannot think a circle without describing it ; we cannot represent, at all, the three dimensions of space, without placing, from the same point, three lines perpendicularly on each other ; nay, we cannot even represent time, except by attending, during our draiving a straight line (which is meant to be the external figurative representation of time) to the act of the synthesis of the manifold only by which we successively determine the internal sense, and thereby to the succession of that determination in it. It is really motion, as the act of the subject (not as the determination of an object 1), therefore the ' Motion of an object in space does not belong to a pure science, Gg 2 452 SUPPLEMENT XIV. synthesis of the manifold in space, (abstraction being made of space, and our attention fixed on the act only by which we determine the internal sense, ac- cording to its form) which first produces the very concept of succession. The understanding does not, therefore, find in it such a connection of the mani- fold, but produces it by affecting the internal sense. It may seem difficult to understand how the think- ing Ego can be different from the Ego which sees or perceives itself (other modes of intuition being at least conceivable), and yet identical with the latter as the same subject, and how, therefore, I can say: I, as intelhgence and thinking subject, know mj-self as an object thought, so far as being given to myself in intuition also, Hke other phenomena only, not as I am to the understanding, but as I appear to my- self. In reality, however, this is neither more nor less difficult than how I can be, to myself, an object, and an object of intuition as well as of internal per- ceptions. But that this must really be so, can clearly be shown, — if only we admit space to be merely a pure form of the phenomena of the external senses, — ■ by the fact that we cannot represent to ourselves time, which is no object of internal intuition, in any other way than under the image of a line which we draw, a mode of representation without which we could not realise the unity of its dimension ; or again by this other fact that we must always derive the determination of the length of time, or of points consequently not to geometry, because tlie fact that a thing is moveable cannot be known a iiriori, but from experience only. Motion, however, considered as describing a space, is a pure act of successive synthesis of the manifold in external intuition in general by means of productive imagination, and belongs, therefore, by right, not only to geometry, but even to transcendental philosophy. SUPPLEMENT XIV. 453 of time, for all our internal perceptions, from that which is represented to us as changeable by external things, and have therefore to arrange the determina- tions of the internal sense as phenomena in time, in exactly the same way in which we arrange the de- terminations of the external senses in space. If, then, with regard to the latter, we admit that by them we know objects so far only as we are affected externally, we must also admit, with regard to the internal sense, that by it we only are, or perceive ourselves, as we are internally affected by ourselves, in other words, that with regard to internal in- tuition we know our own self as a phenomenon only, and not as it is by itself i. § 25- In the transcendental synthesis, however, of the manifold of representations in general, and therefore in the original synthetical unity of apperception, I am conscious of myself, neither as I appear to my- self, nor as I am by myself, but only that I am. This representation is an act of thought, not of in- tuition. Now, in order to kiiow ourselves, we require, besides the act of thinking, which brings the mani- fold of every possible intuition to the unity of ap- perception, a definite kind of intuition also by which that manifold is given, and thus, though my own existence is not phenomenal (much less a mere illu- ' I do not see how so mucli difficulty should be found in ad- mitting that the internal sense is affected by ourselves. Every act of attention gives us an instance of it. In such an act the under- standing always determines the internal sense, according to the connection which it thinks, to such an internal intuition as cor- responds to the manifold in the synthesis of the understanding. How much the mind is commonly affected thereby anybody will be able to perceive in himself. 454 SUPPLEMENT XIV. sion), yet the determination of my existence ^ can only take place according to tlie form of the internal sense, and in that special manner in which the mani- fold, which I connect, is given in the internal intuition. This shows that I have no knowledge of myself as I am, but only as I appear to myself The con- sciousness of oneself is therefore very far from being a knowledge of oneself, in spite of all the categories which constitute the thinking of an object in general, by means of the connection of the manifold in an apperception. As for the knowledge of an object dif- ferent from myself I require, besides the thinking of an object in general (in a category), an intuition also, to determine that general concept? I require for the knowledge of my own self, besides consciovisness, or besides my thinking myself, an intuition also of the manifold in me, to determine that thought. I exist, therefore, as an intelligence, being simply conscious of my power of connection : but with respect to the manifold that has to be connected, I am subject to a limiting condition which is called the internal sense, ^ The I think expresses the act of determining my own ex- istence. What is thus given is the existence, but what is not yet given, is the manner in which I am to determine it, that is, in which I am to place within me the manifold belonging to it. For that purpose self-intuition is required, which depends on an a priori form, that is, on time, which is sensuous, and belongs to our receptivity of what is given to us as determinable. If, then, I have not another self-intuition which, likewise before the act of de- termination, gives the determining within me, of the spontaneity of which I am conscious only, as tim.e gives the determinable, I cannot determine my existence as that of a spontaneously acting being, but I only represent to myself the spontaneity of my thinking, that is, of the act of determination, my existence re- maining sensuous only, that is, determinable, as the existence of a phenomenon. It is on account of this spontaneity that I call myself an intelligence. SUPPLEMENT XIV. 455 according to which that connection can only become perceptible in relations of time, which lie entirely outside the concepts of the understanding. Svich an intelligence, therefore, can only know itself as it ap- pears to itself in an intuition (which cannot be intellectual and given by the understanding itself), and not as it would know itself, if its intuition were intellectual. $26. Transcendental Deduction of the universally possible employment of the p%ire Concepts of the Under- standing in Experience. In the metaphysical deduction of the categories their a priori origin was proved by their complete accordance with the general logical functions of thought, while in their transcendental deduction we estabhshed their possibility as knowledge a priori of objects of an intuition in general (^ 20, 21). Now we have to explain the possibility of our knowing a priori, by means of the categories, whatever ob- jects may come before our senses, and this not ac- cording to the form of their intuition, but according to the laws of their connection, and of our thus, as it were, prescribing laws to nature, nay, making nature possible. Unless they were adequate to that purpose, we could not understand how everything that may come before our senses must be subject to laws which have their origin a priori in the under- standing alone. First of all, I observe that by the synthesis of apprehension I understand the connection of the manifold in an empirical intuition, by which percep- 456 SUPPLEMENT XIV. tion, that is, empirical consciousness of it (as phe- nomenal), becomes possible. We have a jjriori forms of the external as well as the internal intuition, in our representations of space and time : and to these the synthesis of the apprehension of the manifold in phenomena must always conform, because it can take place according to that form only. Time and space, however, are represented a priori, not only as forms of sensuous intuition, but as intuitions themselves (containing a manifold), and therefore with the determination of the unity of that manifold in them (see Transcen- dental Jilsthetic 1). Therefore unity of the synthesis of the manifold without or within us, and conse- quently a connection to which everything that is to be represented as determined in space and time must conform,/ is given a priori as the condition of the synthesis of all apprehension simultaneously loith the intuition^, not in them, and that synthetical unity can be no other but that of the connection of the manifold of any intuition whatsoever, given in an original consciousness, according to the categories, only applied to our sensuous intuition. Consequently, ' Space, represented as an object, (as required in geometry) contains more than the mere form of intuition, namely, the com- frehension of the manifold, which is given according to the form of sensibility, into a perceiitible (intuitable) representation, so that the form of intuition gives the manifold only, while the formal intuition gives unity of representation. In the Esthetic I had simply ascribed this unity to sensibility, in order to show that it precedes all concepts, though it presupposes a synthesis not be- longing to the senses, and by which all concepts of space and time become first possible. For as by that synthesis (the understanding determining the sensibility) space and time are first given as in- tuitions, the unity of that intuition a imori belongs to space and time, and not to the concept of the understanding. (See § 24.) SUPPLEMENT XIV. 457 all synthesis, without which even perception would be impossible, is subject to the categories; and as experience consists of knowledge by means of con- nected perceptions, the categories are conditions of the possibility of experience, and valid therefore a priori for all objects of experience. ***** If, for instance, I raise the empirical inttxition of a house, through the apprehension of the manifold con- tained therein, into a perception, the necessary unity of space and of external sensuous intuition in general is presupposed, and I draw, as it were, the shape of the house according to that synthetical unity of the manifold in space. But this very synthetical unity, if I make abstraction of the form of space, has its seat in the vmderstanding, and is in fact the category of the synthesis of the homogeneous in intuition in general : that is, the category of quantity, to which that synthesis of apprehension, that is, the perception, must always conform ^. Or if, to take another example, I perceive the freezing of water, I apprehend two states (that of fluidity and that of solidity), and these as standing to each other in a relation of time. But in the time, which as internal intuition I make the founda- tion of the phenomenon, I represent to myself neces- sarily synthetical unity of the manifold, without which that relation could not be given as determined in an intuition (with reference to the succession of time). ' In this manner it is proved that the synthesis of apprehension must necessarily conform to the synthesis of apperception, which is intellectual, and contained in the category entirely a priori. It is one and the same spontaneity, which there, under the name of imagination, and here, under the name of understanding, brings connection into the manifold of intuition. 458 SUPPLEMENT XIV. That sjTithetical unity, however, as a condition a priori, under which I connect the manifold of any intuition, turns out to be, if I make abstraction of the perma- nent form of my intuition, namely, of time, the category of cause, through which, if I apply it to my sensibility, I determine everytlmig that hajppens, ac- cording to its relation in time. Thus the appre- hension in such an event, and that event itself con- sidered as a possible perception, is subject to the concept of the relation of cause and effect. The same applies to all other cases. •J" JP ifC JP 'I* Categories are concepts which a priori prescribe laws to all phenomena, and therefore to nature as the sum total of all phenomena (natura materialiter spectata). The question therefore arises, as these laws are not derived from nature, and conform to it as their model (in which case they would be empiri- cal only), how we can understand that nature should conform to them, that is, how they can determine a priori the connection of the manifold in nature, without taking that connection from nature. The solution of that riddle is this. It is no more surprising that the laws of phe- nomena in nature must agree with the understand- ing and its form a priori, that is, with its power of connecting the manifold in general, than that the phenomena themselves must agree with the form of sensuous intuition a priori. For laws exist as little in phenomena themselves, but relatively only, with respect to the subject to which, so far as it has understanding, the phenomena belong, as phenomena exist by themselves, but relatively only, with respect to the same being so far as it has senses. Things by themselves would necessarily possess their con- SUPPLEMENT XIV. 459 formitj to the law, independent also of any under- standing by which they are known. But phenomena are only representations of things, unknown as to what they may be by themselves. As mere repre- sentations they are subject to no law of connection, except that which is prescribed by the connecting faculty. Now that which connects the manifold of sensuous intuition is the faculty of imagination, which receives from the understanding the unity of its intellectual synthesis, and from sensibility the manifoldness of apprehension. Thus, as all possible perceptions depend on the synthesis of apprehension, and that synthesis itself, that empirical synthesis, depends on the transcendental, and therefore on the categories, it follows that all possible perceptions, everything in fact that can come to the empirical consciousness, that is, aU phenomena of nature, must, so far as their connection is concerned, be subject to the categories. On these categories, therefore, nature (considered as nature in general) depends, as on the original groimd of its necessary conformity to law (as natura formaliter spectata). Beyond the laws, on which nature in general, as a lawful order of phenomena in space and time depends, the pure faculty of the under- standing is incapable, by means of mere categories, of prescribing a jyriori laws to phenomena. Special laws, therefore, as they refer to phenomena which are empirically determined, cannot be completely de- rived from the categories, although they are all subject to them. Experience must be superadded in order to know such special laws : wlaile those other a priori laws inform us only with regard to experience in general, and what can be known as an object of it. 460 SUPPLEMENT XIV. § 27- Results of this Deduction of the Conce])ts of the Understanding. We cannot think any object except by means of the categories ; we cannot hnoiv any subject that has been thought, except by means of intuitions, corres- ponding to those concepts. Now all our intuitions are sensuous, and this knowledge, so far as its object is given, is empirical. But empirical knowledge is experience, and therefore no knoivledge a priori is possible to us, except of objects of possible experience only^. This knowledge, however, though limited to objects of experience, is not therefore entirely derived from experience, for both the pure intuitions and the pure concepts of the understanding are elements of know- ledge which exist in us a priori. Now there are only two ways in which a necessary harmony of experience with the concepts of its objects can be conceived ; either experience makes these concepts possible, or these concepts make experience possible. The former will not hold good with respect to the ^ Lest anybody should be unnecessarily frightened by the dan- gerous consequences of this proposition, I shall only remark that the categories are not limited for the purpose of tJiought by the conditions of our sensuous intuition, but have really an unlimited field. It is only the knowledge, of that which we think, the de- termining of an object, that requires intuition, and even in the absence of intuition, the thought of the object may still have its true and useful consequences, so far as the subjective use of reason is concerned. That use of reason, however, as it is not always directed to the determination of the object, that is to knowledge, but also to the determination of the subject, and even its volition, cannot be treated of in this place. SUPPLEMENT XIV. 46 1 categories, (nor with pure sensuous intuition) for they are concepts a priori, and therefore independent of experience. To ascribe to them an empirical origin, would be to admit a kind of generatio sequi- voca. There remains therefore the second alternative only (a kind of system of the epigenesis of pure reason), namely, that the categories, on the part of the understanding, contain the grounds of the possibility of all experience in general. How they render expe- rience possible, and what principles of the possibility of experience they supply in their employment on phenomena, will be shown more fully in the following chapter on the transcendental employment of the faculty of judgment. Some one might propose to adopt a middle way between the two, namely, that the categories are neither self-jjroduced first principles a priori of our knowledge, nor derived from experience, but subjec- tive dispositions of thought, implanted in us with our existence, and so arranged by our Creator that their employment should accurately agree with the laws of nature, which determine experience (a kind of system of preformation of pure reason). But, in that case, not only would there be no end of such an hypothesis, so that no one could know how far the supposition of predetermined dispositions to future judgments might be carried, but there is this decided objection against that middle course that, by adopt- ing it, the categories would lose that necessity which is essential to them. Thus the concept of cause, which asserts, under a presupposed condition, the necessity of an effect, would become false, if it rested only on some subjective necessity implanted in us of connecting certain empirical representations according to the rule of causal relation. I should not be able 462 SUPPLEMENT XIV. to say that the effect is connected with the cause in the object (that is, by necessity), but only, I am so constituted that I cannot think these representations as connected in any other way. This is exactly what the sceptic most desires, for in that case all our knowledge, resting on the supposed objective validity of our judgments, is nothing but mere illusion, nor would there be wanting people to say they knew nothing of such subjective necessity (which can only be felt) ; and at all events we could not quarrel with anybody about what depends only on the manner in which his own subject is organised. Comprehensive View of this Deduction. The deduction of the pure concepts of the under- standing (and with them of all theoretical knowledge a priori) consists in representing them as principles of the possibility of experience, and in representing experience as the determination of phenomena in sjoace and time, — and, lastly, in representing that determi- nation as depending on the principle of the original synthetical unity of apperception, as the form of the understanding apphed to space and time, the origmal forms of sensibility^. ' Kant does not carry the division into paragraphs in his second edition further, because, as he says, he has to treat no more of elementary concepts, and prefers, in representing their employment, to adopt a continuous treatment without paragraphs. SUPPLEMENT XV. [see voi. u. p. 143] All conjunction (conjunctio) is either composition (compositio) or connection (nexus). The former is the synthesis of a manifold the parts of which do not belong to each other necessarily. The two triangles, for instance, into which a square is divided by a diagonal, do by themselves not necessarily belong to each other. Such is the synthesis of the homogeneous, in every- thing that can be considered mathematically, and that synthesis can be divided again into aggregation, and coalition, the former referring to extensive, the latter to intensive qualities. The latter (conjunction nexus) is the synthesis of a manifold, in so far as its elements belong to each other necessarily. Thus the accident belonging to a substance, or the effect belonging to a cause, though heterogeneous, are yet represented as a priori connected, which connection, as it is not arbitrary, I call dynamical, because it concerns the connection of the existence of the mani- fold. This may again be divided into the physical connection of phenomena among each other, and their metaphysical connection in the faculty of cognition a priori. (This forms a note in the 2nd Edition.) SUPPLEMENT XVI a. [see voi. h. p. 143] In the 2nd Edition the title is I. AXIOMS OF INTUITION. Their principle is : all intuitions are extensive quantities. Proof. All phenomena contain, so far as their form is con- cerned, an intuition in space and time, which forms the a priori foundation of all of them. They cannot, therefore, be apprehended, that is, received into empi- rical consciousness, except through the synthesis of the manifold, by which the representations of a defi- nite space or time are produced, i.e. through the synthesis of the homogeneous, and the consciousness of the synthetical unity of that manifold (homoge- neous). Now the consciousness of the manifold and homogeneous in intuition, so far as by it the repre- sentation of an object is first rendered possible, is the concept of quantity (quantum). Therefore even the perception of an object as a phenomenon is possible only through the same synthetical unity of the mani- fold of the given sensuous intuition, by which the unity of the composition of the manifold and homogeneous is conceived in the concept of a quantity; that is, phe- nomena are always quantities, and extensive quan- tities ; because as intuitions in space and time, they must be represented through the same synthesis through which space and time in general are deter- mined. SUPPLEMENT XYI b. [see voi. li. p. 147] II. Anticipations of Perception. Their principle is : In all phenomena the Real, which is the object of a sensation, has intensive quantity, that is, a degree. Proof. Perception is empirical consciousness, 'that is, a consciousness in which there is at the same time sensation. Phenomena, as objects of perception, are not pure (merely formal) intuitions, like space and time (for space and time can never be perceived by themselves). They contain, therefore, over and above the intuition, the material for some one object in general (through which something existing in space and time is represented) ; that is, they contain the real of sensation, as a merely subjective representation, which gives us only the consciousness that the subject is affected, and which is referred to some object in general. Now there is a gradual transition possible from empirical to pure consciousness, till the real of it vanishes completely and there remains a merely formal consciousness (a priori) of the manifold in space and tinTe ; and, therefore, a synthesis also is possible in the production of the quantity of a sen- sation, from its beginning, that is, from the pure intui- tion = o, onwards to any quantity of it. As sensation by itself is no objective representation, and as in it the intuition of neither space nor time can be found, it follows that though not an extensive, yet some TOL. I. H h 466 SUPPLEMENT XVI b. kind of quantity must belong to it (and this through the apprehension of it, in which the empirical con- sciousness may grow in a certain time from nothing = o to any amount). That quantity must be inten- sive, and corresponding to it, an intensive quantity, i.e. a degree of influence upon the senses, must be attributed to all objects of perception, so far as it contains sensation. SUPPLEMENT XYIL [Seevol. n. p. 155] III. Analogies or Experience. Their principle is : experience is' possible only through the representation of a necessary connection of perceptions. Proof. Experience is empirical knowledge, that is, know- ledge which determines an object by means of perceptions. It is, therefore, a synthesis of perceptions, which synthesis itself is not contained in the percep- tion, but contains the synthetical unity of the manifold of the perceptions in a consciousness, that unity constituting the essential of our knowledge of the objects of the senses, i.e. of experience (not only of intuition or of sensation of the senses). In experience perceptions come together contingently only, so that no necessity of their connection could be discovered m the perceptions themselves, apprehen- sion being only a composition of the manifold of empirical intuition, but containing no representation of the necessity of the connected existence of phe- nomena which it places together in space and time. Experience, on the contrary, is a knowledge of objects by perceptions, in which therefore the relation in the existence of the manifold is to be represented, not as it is put together in time, but as it is in time, objec- tively. Now, as time itself cannot be perceived, the H h 2 468 SUPPLEMENT XVII. determination of the existence of objects in time can take place only by their connection in time in general, that is, through concepts connecting them a priori. As these concepts always imply neces- sity, we are justified in saying that experience is possible only through a representation of the necessary connection of perceptions. SUPPLEMENT XVIII. [See vol. H p. i6o] A. First Analogy. Principle of the Permanence of Siihsiance. In all changes of phenomena the substance is perma- nent, and its quantum is neither increased nor diminished in nature. Proof. All phenomena exist in time, and in it alone, as the substratum (as permanent form of the internal intuition) can simuUaneousness as well as succession be represented. Time, therefore, in which all change of phenomena is to be thought, does not change, for it is that in which simultaneousness and succession can be represented as determinations of it. As time by itself cannot be perceived, it follows that the substra- tum which represents time in general, and in which all change or simultaneousness can be perceived in apprehension, through the relation of phenomena to it, must exist in the objects of perception, that is, in the phenomena. Now the substratum of all that is real, that is of all that belongs to the existence of things, is the substance, and all that belongs to existence can be conceived only as a determination of it. Con- sequently the permanent, in reference to which alone all temporal relations of phenomena can be deter- 470 SUPPLEMENT XVIII. mined, is the substance in phenomena, that is, what is real in them, and, as the substratum of all change, remains always the same. As therefore substance cannot change in existence, we were justified in say- ing that its quantum can neither be increased nor diminished in nature. SUPPLEMENT XIX. [see voi. ii. p. lee] B. Second Analogy. Frincijple of the Succession of Time, according to the Law of Causality. All changes take place according to the law of connection between cause and effect. Proof {It has been shown by the preceding principle, that all phenomena in the succession of time are changes only, i. e. a successive being and not-being of the determinations of the substance, which is per- manent, and consequently that the being of the sub- stance itself, which foUows upon its not-being, and its not-being, which follows on its being, — in other words, that an arising or perishing of the substance itself is inadmissible. The same principle might also have been expressed thus : all change [succession) of ^phenomena consists in modification only, for arising and perishing are no modifications of the substance, because the concept of modification presupposes the same subject as existing with two opposite determin- ations, and therefore as permanent. After this pre- liminary remark, we shall proceed to the proof) I perceive that phenomena succeed each other, that is, that there is a state of things at one time the opposite of which existed at a previous time. I am therefore really connecting two perceptions in time. That connection is not a work of the senses onlv and 472 SUPPLEMENT XIX. of intuition, but is here the product of a synthetical power of the faculty of imagination, which determines the internal sense with reference to relation in time. Imagination, however, can connect those two states in two ways, so that either the one or the other pre- cedes in time : for time cannot be perceived by itself, nor can we determine in the object empirically and with reference to time, what precedes and what follows. I am, therefore, conscious only that my imagination places the one before, the other after, and not, that in the object the one state comes before the other. In other words, the objective relation of phe- nomena following upon each other remains unde- termined by mere perception. In order that this may be known as determined, it is necessary to con- ceive the relation between the two states in such a way that it should be determined thereby with necessity, which of the two should be taken as coming first, and which as second, and not conversely. Such a concept, involving a necessity of synthetical unity, can be a pure concept of the understanding only, which is not supplied by experience, and this is, in this case, the concept of the relation of cause and effect, the former determining the latter in time as the consequence, not as something that by imagination might as well be antecedent, or not to be perceived at all. Experience itself, therefore, that is, an empirical knowledge of phenomena, is possible only by our subjecting the succession of phenomena, and with it aU change, to the law of causality, and phenomena themselves, as objects of experience, are consequently possible according to the same law only. SUPPLEMENT XX. [see voi. ii. p. 184] C. Third Analogy. Principle of Coexistence, according to the Law of Reciprocity or Community. All substances, so far as they can be perceived as coexistent in space, are always affecting each other reciprocally. Proof. Things are coexistent when, in empirical intuition, the perception of the one can follow upon the percep- tion of the other, and vice versa, which, as was shown in the second principle, is impossible in the temporal succession of jshenomena. Thus I may first observe the moon and afterwards the earth, or, con- versely also, first the earth and afterwards the moon, and because the perceptions of these objects can foUow each other in both ways, I say that they are coexistent. Now coexistence is the existence of the manifold in the same time. Time itself, however, cannot be perceived, so that we might learn from the fact that things exist in the same time that their perceptions can follow each other reciprocally. The synthesis of imagination in apprehension would, therefore, give us each of these perceptions as exist- ing in the subject, when the other is absent, and vice versa : it would never tell us that the objects are coexistent, that is, that if the one is there, the other 474 SUPPLEMENT XX. also must be there in the same time, and this by necessity, so that the perceptions may follow each other reciprocally. Hence we require a concept of the reciprocal sequence of determinations of things existing at the same time, but outside each other, in order to be able to say, that the reciprocal sequence of the perceptions is founded in the object, and thus to represent their coexistence as objective. The rela- tion of substances, however, of which the first has determinations the ground of which is contained in the other, is the relation of influence, and if, con- versely also, the first contains the ground of deter- minations in the latter, the relation is that of com- munity or reciprocity. Hence the coexistence of substances in space cannot be known in experience otherwise but under the supposition of reciprocal action : and this is therefore the condition also of the possibility of things as objects of experience. SUPPLEMENT XXI. [seevoi. n. p. 197] An important protest, however, against these rules for proving existence mediately is brought forward by Idealism, and this is therefore the proper place for its refutation. Refutation of Idealism. Idealism (I mean material idealism) is the theory which declares the existence of objects in space, without us, as either doubtful only and not demon- strable, or as false and impossible. The former is the ^rohlematical idealism of Descartes, who declares one empirical assertion only to be undoubted, namely, that of I am ; the latter is the dogmatical idealism of Berkeley, who declares space and all things to which it belongs as an inseparable con- dition, as something impossible in itself, and, there- fore, the things in space as mere imaginations. Dogmatic idealism is inevitable, if we look upon space as a property belonging to things by them- selves, for in that case space and all of which it is a condition, would be a non-entity. The ground on which that idealism rests has been removed by us in the Transcendental Esthetic. Problematical idealism, which asserts nothing, but only pleads our inability of proving any existence except our own by means of immediate experience, is reasonable and in accordance with a sound philosophical mode of thought, which allows of no decisive judgment, before a sufficient 476 SUPPLEMENT XXI. proof has been found. The required proof will have to demonstrate that we may have not only an ima- gination, but also an experience of external things, and this it seems can hardly be effected in any other way except by proving that even our internal ex- perience, which Descartes considers as undoubted, is possible only under the supposition of external ex- perience. Theorem. The simfle, hut empirically determined Consciousness of my own existence, proves the Existence of objects in space outside myself Proof I am conscious of my own existence as determined in time, and all determination in time presupposes something permanent in the perception ^. That permanent, however, cannot be an intuition within me, because aU the causes which determine my exist- ence, so far as they can be found within me, are representations, and as such I'equire themselves some- thing permanent, different from them, in reference to which their change, and therefore my existence in the time in which they change, may be deter- mined. The perception of this permanent, therefore, is possible only through a thing outside me, and not through the mere representation of a thing outside me, and the determination of my existence in time is, conse- quently, possible only by the existence of real things, which I perceive outside me. As therefore the con- ' This passage has been translated as amended by Kant himself in the Preface to the Second Edition (p. 386). SUPPLEMENT XXI. 47/ sciotisness in time is necessarily connected with the consciousness of the possibility of that determination of time, it is also necessarily connected with the existence of things outside me, as the condition of the determination of time. In other words, the con- sciousness of my own existence is, at the same time, an immediate consciousness of the existence of other things. Note i. — It will have been perceived that in the foregoing proof the trick played by idealism has been turned against it, and with greater justice. Idealism assumed that the only immediate experience is the internal,