WJ 
 
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AN ENQUIRY 
 
 CONCEBNINO 
 
 HUMAN UNDERSTANDING 
 
 AND SELECTIONS FROM 
 
 A TREATISE OF HUMAN NATURE 
 
 BY 
 DAVID HUME 
 
 WITH HUME'S AUTOBIOGRAPHY AND 
 A LETTER FROM ADAM SMITH 
 
 CHICAGO 
 THE OPEN COURT PUBLISHING CO, 
 « 19/2 
 
/7/^ 
 
PUBLISHERS' PREFACE. 
 
 THE present volume is the second of the series of Phil- 
 osophical Classics which The Open Court Publishing 
 Company purposes issuing in cheap form for the convenience 
 and instruction of the general reading public. It is an un- 
 annotated reprint, merely, of the Enquiry Concerning Human 
 Understanding, made from the posthumous edition of 1777, 
 together with Hume's charming autobiography and the 
 eulogistic letter of Adam Smith, usually prefixed to the 
 History of England. These additions, with the portrait by 
 Ramsay, which forms the frontispiece to the volume, render 
 the picture of Hume's life complete, and leave but a word to 
 be said concerning his philosophical importance. 
 
 With the great public, Hume's fame has always rested 
 upon his History of England, — a work now antiquated as his- 
 tory and remarkable only for the signal elegance and sym- 
 metry of its style. But this once prevalent opinion, our age 
 has reversed, and, as has been well remarked,* "Hume, the 
 spiritual father of Kant, now takes precedence over Hume, the 
 rival of Robertson and Gibbon." It is precisely here, in fact, 
 that Hume's significance for the history of thought lies. With 
 him modern philosophy entered upon its Kantian phase, be- 
 came critical and positivistic, became a theory of knowledge. 
 For the old "false and adulterate" metaphysics he sought to 
 substitute a "true" metaphysics, based on the firm founda- 
 tions of reason and experience. His scepticism, — and of 
 scepticism he has since been made the standard-bearer, — was 
 directed against the old ontology only, and not against science 
 proper (inclusive of philosophy). "Had Hume been an 
 absolute sceptic he could never have produced an Immanuel 
 Kant. . . . The spirit of the theoretical philosophy of Hume 
 and Kant, the fundamental conception of their investigations, 
 and the goal at which they aim, are perfectly identical. Theirs 
 
 •Alfred Weber, History of Philosophy, New York, 1896. 
 
 347201. 
 
PUBLISHERS' PREFACE. 
 
 is the critical spirit, and positive knowledge the goal at which 
 they aim. To claim for Kant the sole honor of having 
 founded criticism is an error which a closer study of British 
 philosophy tends to refute."! 
 
 To this reprint of Hume's Enquiry Concerning Human 
 Undersianding has been added a supplement containing se- 
 lections from his earlier and longer philosophical work, the 
 Treatise on Human Understanding, referred to in the 
 "Author's Advertisement" to the Enquiry (page xxvili., 
 this edition). In spite of Hume's deprecatory reference to 
 the Treatise, it remains the completest expression of his 
 philosophical doctrine. The selected portions of the 
 Treatise comprise (i) certain sections on causality which 
 amplify the causal doctrine of the Enquiry and may profit- 
 ably be read after Section VH. of the latter work; and (2) 
 those sections which embody the essential features of Hume's 
 constructive philosophy, his conception of matter and of self 
 of spirit. Nothing in the Enquiry, with the exception of a 
 few paragraphs of Section XH., corresponds to these sections 
 of the Treatise. They should be read before, or in place 
 of, the comparatively irrelevant sections, IX-XL, of the 
 Enquiry. 
 
 The first part of this book, pages i to 174, has been edited 
 by Mr. Thomas J. McCormack of La Salle, 111., now principal 
 of the La Salle Township High School. The remainder, 
 pages 17s to 263, has been edited by Prof. Mary Whiten 
 Calkins, of Wellesley College, Wellesley, Mass. 
 
 THE OPEN COURT PUBLISHING CO. 
 March, 1907. 
 t Weber, loc. cit., pp. 4i9-4?o, 
 
 ? 
 
 ./> 
 
THE LIFE OF DAVID HUME, ESQ, 
 
 WRITTEN BY HIMSELF. 
 
 MY OWN LIFE. 
 
 TT is difficult for a man to speak long of himself 
 -*- without vanity; therefore I shall be short. It may 
 be thought an instance of vanity that I pretend at all 
 to write my life ; but this narrative shall contain little 
 more than the history of my writings; as, indeed, al 
 most all my life has been spent in literary pursuits 
 and occupations. The first success of most of my 
 writings was not such as to be an object of vanity. 
 
 I was born the twenty-sixth of April, 1711, old 
 style, at Edinburgh. I was of a good family, both 
 by father and mother : my father's family is a branch 
 of the earl of Home's, or Hume's ; and my ancestors 
 , had been proprietors of the estate which my brother 
 possesses, for several generations. My mother was 
 daughter of Sir David Falconer, president of the col-; 
 lege of justice ; the title of Lord Halkerton came by 
 succession to her brother. 
 
 My family, however, was not rich ; and being my- 
 self a younger brother, my patrimony, according to 
 the mode of my country, was of course very slender. 
 
vi AUTOBIOGRAPHY, 
 
 My father, who passed for a man of parts, died when 
 I was an infant, leaving me, with an elder brother aqid 
 a sister, under the care of our mother, a woman of 
 singular merit, who, though young and handsome, 
 devoted herself entirely to the rearing and educating 
 of her children. I passed through the ordinary course 
 of education with success, and was seized very early 
 with a passion for literature, which has been the ru- 
 ling passion of my life, and the great source of my en- 
 joyments. My studious disposition, my sobriety, and 
 my industry, gave my family a notion that the law 
 was a proper profession for me; but I found an insur- 
 mountable aversion to every thing but the pursuits of 
 philosophy and general learning; and while they 
 fancied I was poring upon Voet and Vinnius, Cicero 
 and Virgil were the authors which I was secretly 
 devouring. 
 
 My very slender fortune, however, being unsuitable 
 to this plan of life, and my health being a little broken 
 by my ardent application, I was tempted, or rather 
 forced, to make a very feeble trial for entering into a 
 more active scene of life. In 1734, I went to Bristol, 
 with some recommendations to several eminent mer- 
 chants ; but in a few months found that scene totally 
 unsuitable to me. I went over to France, with a view 
 of prosecuting my studies in a country retreat ; and I 
 there laid that plan of life which I have steadily and 
 successfully pursued. I resolved to make a very rigid 
 frugality supply my deficiency of fortune, to maintain 
 
AUTOBIOGRAPHY. v\i 
 
 unimpaired my independency, and to regard every 
 object as contemptible, except the improvements of 
 my talents in literature. 
 
 During my retreat in France, first at Rheims, but 
 chiefly at La Fleche, in Anjou, I composed my Trea- 
 tise of Human Nature. After passing three years very 
 agreeably in that country, I came over to London in 
 1737. In the end of 1738, I published my Treatise, 
 and immediately went down to my mother and my 
 brother, who lived at his country house, and was 
 employing himself very judiciously and successfully 
 in the improvement of his fortune. 
 
 Never literary attempt was more unfortunate than 
 my Treatise of Human Nature. It fell dead-born 
 from the press, without reaching such distinction as 
 even to. excite a murmur among the zealots. But be- 
 ing naturally of a cheerful and sangume temper, I very 
 soon recovered the blow, and prosecuted with great 
 ardor my studies in the country. In 1742, I printed 
 at Edinburgh the first part of my Essays. The work 
 was favorably received, and soon made me entirely 
 forget my former disappointment. I continued with 
 my mother and brother in the country, and in that 
 time recovered the knowledge of the Greek language, 
 which I had too much neglected in my early youth. 
 
 In 1745, I received a letter from the marquis of 
 Annandale, inviting me to come and live with him in 
 England ; I found also that the friends and family of 
 that young nobleman were desirous of putting him 
 
j^iil AUTOBIOGRAPHY. 
 
 \ 
 
 under my care and direction, for the state of his mind 
 
 and health required it. I lived with him a twelve- 
 month. My appointments during that time made a 
 considerable accession to my small forture. I then 
 received an invitation from General St. Clair to attend 
 him as a secretary to his expedition, which was at first 
 meant against Canada, but ended in an incursion on 
 the coast of France. Next year, to wit, 1747, I re- 
 ceived an invitation from the general to attend him in 
 the same station in his military embassy to the courts 
 of Vienna and Turin. I then wore the uniform of an 
 officer, and was introduced at these courts as aid-de- 
 camp to the general, along with Sir Harry Erskine and 
 Captain Grant, now General Grant. These two years 
 were almost the only interruptions which my studies 
 have received during the course of my life : I passed 
 them agreeably, and in good company ; and my ap- 
 pointments, with my frugality, had made me reach a 
 fortune which I called independent, though most of 
 my friends were inclined to smile when I said so : in 
 short, I was now master of neafls^^ousand pounds. 
 
 I had always entertained a il^fon, that my want 
 of success in publishing the Treatise of Human Na- 
 ture had proceeded more from the manner than the 
 matter, and that I had been guilty of a very usual 
 indiscretion, in going to the press too early. I, there- 
 fore, cast the first part of that work anew in the In- 
 quiry concerning Human Understanding, which was 
 published while I was at Turin. But this piece was 
 
A U TO BIO GRAPH Y, ix 
 
 at first little more successful than the Treatise on 
 Human Nature. On my return from Italy, I had 
 the mortification to find all England in a ferment, on 
 account of Dr. Middleton's Free Inquiry^ while my 
 performance was entirely overlooked and neglected. 
 A new edition, which had been published at London, 
 of my Essays, moral and political, met not with a 
 much better reception. 
 
 9 Such is the force of natural temper, that these dis- 
 appointments made little or no impression on me. I 
 went down, in 1749, and lived two years with my 
 brother at his country house, for my mother was now 
 dead. I there composed the second part of my Essay, 
 which I called Political Discourses, and also my In- 
 quiry concerning the Principles of Morals, which is 
 another part of my Treatise that I cast anew. Mean- 
 while, my bookseller, A. Millar, informed me, that my 
 former publications (all but the unfortunate Treatise) 
 were beginning to be the subject of conversation; 
 that the sale of them was gradually increasing, and 
 that new editions were demanded. Answers by rev- 
 erends and right reverends came out two or three in 
 a year ; and I found, by Dr. Warburton's railing, that 
 the books were beginning to be esteemed in good 
 company. However, I had fixed a resolution, which 
 i inflexibly maintained, never to reply to any body; 
 and not being very irascible in my temper, I have 
 easily kept myself clear of all literary squabbles. These 
 symptoms of a rising reputation gave me encourage- 
 
X AUTOBIOGRAPHY, 
 
 ment, as I was ever more disposed to see the favorable 
 than unfavorable side of things; a turn of mind which 
 it is more happy to possess, than to be born to an 
 estate of ten thousand a year. 
 
 In 1 75 1, I removed from the country to the town, 
 the true scene for a man of letters. In 1752 were 
 published at Edinburgh, where I then lived, my Politi- 
 cal Discourses, the only work of mine that was suc- 
 cessful on the first publication. It was well received 
 at home and abroad. In the same year was published, 
 at London, my Inquiry concerning the Principles of 
 Morals ; which, in my own opinion, (who ought not 
 to judge on that subject,) is, of all my writings, his- 
 torical, philosophical, or literary, incomparably the 
 best. It came unnoticed and unobserved into the 
 world. 
 
 In 1752, the Faculty of Advocates chose me their 
 librarian, an office from which I received little or no 
 emolument, but which gave me the command of a 
 large library. I then formed the plan of writing the 
 History of England; but being frightened with the 
 notion of continuing a narrative through a period of 
 seventeen hundred years, I commenced with the acces- 
 sion of the house of Stuart, an epoch when, I thought, 
 the misrepresentations of faction began chiefly to take 
 place. I was, I own, sanguine in my expectations of 
 the success of this work. I thought that I was the 
 only historian that had at once Biftglected present 
 power, interest and authority, and the cry of popular 
 
A UTOBIOGRAPHY. xi 
 
 prejudices; and as the subject was suited to every 
 capacity, I expected proportional applause. But mis- 
 erable was my disappointment ; I was assailed by one 
 cry of reproach, disapprobation, and even detestation; 
 English, Scotch, and Irish, whig and tory, churchman 
 and sectary, freethinker and religionist, patriot and 
 courtier, united in their rage against the man who 
 had presumed to shed a generous tear for the fate of 
 Charles I. and the earl of Strafford; and after the 
 first ebullitions of their fury were over, what was still 
 more mortifying, the book seemed to sink into obliv- 
 ion. Mr. Millar told me that in a twelvemonth he 
 sold only forty-five copies of it. I scarcely, indeed, 
 heard of one man in the three kingdoms, considerable 
 for rank or letters, that could endure the book. I 
 must only except the primate of England, Dr. Her- 
 ring, and the primate of Ireland, Dr. Stone, which 
 seem two odd exceptions. These dignified prelates 
 separately sent me messages not to be discouraged. 
 
 I was, however, I confess, discouraged ; and had 
 not the war been at that time breaking out between 
 France and England, I had certainly retired to some 
 provincial town of the former kingdom, have changed 
 my name, and never more have returned to my native 
 country. But as this scheme was not now practica- 
 ble, and the subsequent volume was considerably 
 advanced, I resolved to pick up courage and to per- 
 severe. 
 
 In this interval, I published, at London, my Natu- 
 
xU AUTOBIOGRAPHY, 
 
 ral History of Religion, along with some other small 
 pieces. Its public entry was rather obscure, except 
 only that Dr. Hurd wrote a pamphlet against it, with 
 all the illiberal petulance, arrogance, and scurrility, 
 which distinguish the Warburtonian school. This 
 pamphlet gave me some consolation for the other- 
 wise indifferent reception of my performance. 
 
 In 1756, two y^ars after the fall of the first volume, 
 was published the second volume of my history, con- 
 taining the period from the death of Charles I. till the 
 revolution. This performance happened to give less 
 displeasure to the whigs, and was better received. 
 It not only rose itself, but helped to buoy up its un- 
 fortunate brother. 
 
 But though I had been taught by experience that 
 the whig party were in possession of bestowing all 
 places, both in the state and in literature, I was so 
 little inclined to yield to their senseless clamor, that 
 in above a hundred alterations, which further study, 
 reading, or reflection engaged me to make in the 
 reigns of the two first Stuarts, I have made all of 
 them invariably to the tory side. It is ridiculous to 
 consider the English constitution before that period 
 as a regular plan of liberty. 
 
 In 1759, I published my history of the house of 
 Tudor. The clamor against this performance was 
 almost equal to that against the history of the two 
 first Stuarts. The reign of Elizabeth was particularly 
 obnoxious. But I was now callous against the im 
 
AUTOBIOGRAPHY. sUi 
 
 pressions of public folly, and continued very peaceably 
 and contentedly, in my retreat at Edinburgh, to finish, 
 in two volumes, the more early part of the English 
 history, which I gave to the public in 1761, with 
 tolerable, and but tolerable, success. 
 
 But, notwithstanding this variety of winds and 
 seasons, to which my writings had been exposed, they 
 had still been making such advances, that the copy- 
 money given me by the booksellers much exceeded any 
 thing formerly known in England ; I was become not 
 only independent, but opulent. I retired to my native 
 country of Scotland, determined never more to set my 
 foot out of it ; and retaining the satisfaction of never 
 having preferred a request to one great man, or even 
 making advances of friendship to any of them. As I 
 was now turned of fifty, I thought of passing all the 
 rest of my life in this philosophical manner : when I 
 received, in 1763, an invitation from the earl of Hert- 
 ford, with whom I was not in the least acquainted, to 
 attend him on his embassy to Paris, with a near pros- 
 pect of being appointed secretary to the embassy; and, 
 in the mean while, of performing the functions of that 
 office. This offer, however inviting, I at first declined; 
 both because I was reluctant to begin connections 
 with the great, and because I was afraid that the 
 civilities and gay company of Paris would prove dis- 
 agreeable to a person of my age and humor ; but on 
 his lordship's repeating the invitation, I accepted of it. 
 I have every reason, both of pleasure and interest, to 
 
xW AUTOBIOGRAPHY, 
 
 think myself happy in my connexions with that noble- 
 man, as well as afterwards with his brother, General 
 Conway. 
 
 Those who have not seen the strange effects of 
 modes, will never imagine the reception I met with at 
 Paris, from men and women of all ranks and stations. 
 The more I resiled from their excessive civilities, the 
 more I was loaded with them. There is, however, 
 a real satisfaction in living at Paris, from the great 
 number of sensible, knowing, and polite company 
 with which that city abounds above all places in the 
 universe. I thought once of settling there for life. 
 
 I was appointed secretary to the embassy ; and, in 
 summer, 1765, Lord Hertford left me, being appointed 
 lord lieutenant of Ireland. I was charge d'affaires till 
 the arrival of the duke of Richmond, towards the end 
 of the year. In the beginning of 17&6, I left Paris, 
 and next summer went to Edinburgh, with the same 
 view as formerly, of burying myself in a philosophical 
 retreat. I returned to that place, not richer, but with 
 much more money, and a much larger income, by 
 means of Lord Hertford's friendship, than I left it; 
 and I was desirous of trying what superfluity could 
 produce, as I had formerly made an experiment of a 
 competency. But in 1767, I received from Mr. Con- 
 way an invitation to be under-secretary ; and this 
 invitation, both the character of the person, and mv 
 connexions with Lord Hertford, prevented me from 
 declining. I returned to Edinburgh in 1769, very 
 
AUTOBIOGRAPHY, xv 
 
 opulent, (for I possessed a revenue of one thousand 
 pounds a year,) healthy, and though somewhat stricken 
 in years, with the prospect of enjoying long my ease? 
 and of seeing the increase of my reputation. 
 
 In spring, 1775, I was struck with a disorder in 
 my bowels, which at first gave me no alarm, but has 
 since, as I apprehend it, become mortal and incurable. 
 I now reckon upon a speedy dissolution. I have suf- 
 fered very little pain from my disorder ; and what is 
 more strange, have, notwithstanding the great decline 
 of my person, never suffered a moment's abatement 
 of my spirits; insomuch, that were I to name a period 
 of my life which I should most choose to pass over 
 again, I might be tempted to point to this later period. 
 I possess the same ardor as ever in study, and the same 
 gayety in company. I consider, besides, that a man 
 of sixty-five, by dying, cuts off only a few years of 
 infirmities ; and though I see many symptoms of my 
 literary reputaticsn's breaking out at last with addi- 
 tional lustre, I kriiow that I could have but few years 
 to enjoy it. It is difficult to be more detached from 
 life than I am at present. 
 
 To conclude historically with my own character: 
 I am, or rather was, (for that is the style I must now 
 use in speaking of myself, which emboldens me the 
 more to speak my sentiments;) I was, I say, a man of 
 mild disposition, of command of temper, of an open 
 social, and cheerful humor, capable of attachment, but 
 little susceptible of enmity, and of great moderation 
 
% 
 xvi AUTOBIOGRAPHY. 
 
 in all my passions. Even my love of literary fame, 
 my ruling passion, never soured my temper, notwith- 
 standing my frequent disappointments. My companyj 
 was not unacceptable to the young and careless, as 
 well as to the studious and literary; and as I took a 
 particular pleasure in the company of modest women, 
 I had no reason to be displeased with the reception I 
 met with from them. In a word, though most men, 
 anywise eminent, have found reason to complain of 
 Calumny, I never was touched, or even attacked, by 
 her baleful tooth; and though I wantonly exposed 
 myself to the rage of both civil and religious factions, 
 they seemed to be disarmed in my behalf of their 
 wonted fury. My friends never had occasion to vin- 
 dicate any one circumstance of my character and con- 
 duct ; not but that the zealots, we may well suppose, 
 would have been glad to invent and propagate any 
 story to my disadvantage, but they could never find 
 any which they thought would wear the face of prob- 
 ability. I cannot say there is no vanity in making this 
 funeral oration of myself, but I hope it is not a mis- 
 placed one; and this is a matter of fact which is easily 
 cleared and ascertained. 
 
 April i8, 1776. 
 
LETTER FROM ADAM SMITH, LL. D. 
 
 TO WILLIAM STRAHAN, ESQ. 
 
 KiRKALDY, FiFESHIRE, NoV. Q, 1 776. 
 
 Dear Sir, 
 
 IT is with a real, though a very melancholy pleasure, 
 that I sit down to give you some account of the 
 behaviour of our late excellent friend, Mr. Hume, 
 during his last illness. 
 
 Though, in his own judgement, his disease was 
 mortal and incurable, yet he allowed himself to be 
 prevailed upon, by the entreaty of his friends, to try 
 what might be the effects of a long journey. A few 
 days before he set out, he wrote that account of hi5 
 own life, which, together with his other papers, he 
 has left to your care. My account, therefore, shall 
 begin where his ends. 
 
 He set out for London towards the end of April, 
 and at Morpeth met with Mr. John Home and myself, 
 who had both come down from London on purpose to 
 see him, expecting to have found him at Edinburgh. 
 Mr. Home returned with him, and attended him dur- 
 ing the whole of his stay in England, with that care 
 and attention which might be expected from a temper 
 
xviii LETTER FROM ADAM SMITH, 
 
 SO perfectly friendly and affectionate As I had written 
 to my mother that she might expect me in Scotland, 
 I was under the necessity of continuing my journey. 
 His disease seemed to yield to exercise and change of 
 air; and when he arrived in London, he was apparently 
 in much better health than when he left Edinburgh. 
 He was advised to go to Bath to drink the waters, 
 which appeared for some time to have so good an effect 
 upon him, that even he himself began to entertain, 
 what he was not apt to do, a better opinion of his own 
 health. His symptoms, however, soon returned with 
 their usual violence; and from that moment he gave 
 up all thoughts of recovery, but submitted with the 
 utmost cheerfulness, and the most perfect compla- 
 cency and resignation. Upon his return to Edinburgh, 
 though he found himself much weaker, yet his cheer- 
 fulness never abated, and he continued to divert him- 
 self, as usual, with correcting his own works for a new 
 editiosi, with reading books of amusement, with the 
 conversation of his friends ; and, sometimes in the 
 evening, with a party at his favorite game of whist 
 His cheerfulness was so great, and his conversation 
 and amusements ran so much in their usual strain, 
 that, notwithstanding all bad symptoms, many people 
 could not believe he was dying. "I shall tell your 
 friend. Colonel Edmonstone,'*said Dr. Dundas to him 
 one day, *'that I left you much better, and in a fair 
 way of recovery." *' Doctor," said he, '*as I believe 
 you would not choose to tell any thing but the truth, 
 
LETTER FROM ADAM SMITH, xix 
 
 you had better tell him that I am dying as fast as my 
 enemies, if I have any, could wish, and as easily and 
 cheerfully as my best friends could desire. " Colonel 
 Edmonstone soon afterwards came to see him, and 
 take leave of him ; and on his way home he could not 
 forbear writing him a letter, bidding him once more 
 an eternal adieu, and applying to him, as to a dying 
 man, the beautiful French verses in which the Abbd 
 Chaulieu, in expectation of his own death, laments his 
 approaching separation from his friend the Marquis 
 de la Fare. Mr. Hume's magnanimity and firmness 
 were such, that his most affectionate friends knew 
 that they hazarded nothing in talking or writing to 
 him as to a dying man, and that so far from being 
 hurt by this frankness, he was rather pleased and flat- 
 tered by it. I happened to come into his room while 
 he was reading this letter, which he had just received, 
 and which he immediately showed me. I told him, 
 that though I was sensible how very much he was 
 weakened, and that appearances were In many respects 
 very bad, yet his cheerfulness was still so great, the 
 spirit of life seemed still to be so very strong in him, 
 that I could not help entertaining some faint hopes. 
 He answered, "Your hopes are groundless. An ha- 
 bitual diarrhoea of more than a year's standing, would 
 be a very bad disease at any age ; at my age it is a 
 mortal one. When I lie down in the evening, I feel 
 myself weaker than when I rose In the morning ; and 
 when I rise in the morning, weaker than when I lay 
 
XX LETTER FROM ADAM SMITH. 
 
 down in the evening. I am sensible, besides, that 
 some of my vital parts are affected, so that I must 
 soon die." **Well," said I, ''if it must be so, you 
 have at least the satisfaction of leaving all your friends, 
 your brother's family in particular, in great prosper- 
 ity." He said that he felt that satisfaction so sensibly, 
 that when he was reading, a few days before, Lucian's 
 Dialogues of the Dead, among all the excuses which 
 are alleged to Charon for not entering readily into his 
 boat, he could not find one that fitted him : he had no 
 house to finish, he had no daughter to provide for, he 
 had no enemies upon whom he wished to revenge 
 himself. *'I could not well imagine," said he, *'what 
 excuse I could make to Charon in order to obtain a 
 little delay. I have done every thing of consequence 
 which I ever meant to do ; and I could at no time ex- 
 pect to leave my relations and friends in a better sit- 
 uation than that in which I am now likel}^ to leave them: 
 I, therefore, have all reason to die contented." He 
 then diverted himself with inventing several jocular 
 excuses, which he supposed he might make to Charon, 
 and with imagining the very surly answers which it 
 might suit the character of Charon to return to them. 
 '«Upon further consideration," said he, **I thought I 
 might say to him, 'Good Charon, I have been correct- 
 ing my works for a new edition. Allow me a little 
 time, that I may see how the public receives the alter- 
 ations.' But Charon would answer, 'When you have 
 seen the effect of these, you will be for making other 
 
LETTER FROM ADAM SMITH. xxi 
 
 alterations. There will be no end of such excuses ; 
 so, honest friend, please step into the boat.* But I 
 might still urge, *Have a little patience, good Charon: 
 I have been endeavouring to open the eyes of the pub- 
 lic. If I live a few years longer, I may have the satis- 
 faction of seeing the downfall of some of the prevailing 
 systems of superstition.' But Charon would then lose 
 all temper and decency. * You loitering rogue, that will 
 not happen these many hundred years. Do you fancy 
 I will grant you a lease for so long a term ? Get into 
 the boat this instant, you lazy, loitering rogue.* " 
 
 But, though Mr. Hume always talked of his ap- 
 proaching dissolution with great cheerfulness, he never 
 affected to make any parade of his magnanimity. He 
 never mentioned the subject but when the conversa- 
 tion naturally led to it, and never dwelt longer upon 
 it than the course of the conversation happened to re- 
 quire ; it was a subject indeed which occurred pretty 
 frequently, in consequence of the inquiries which his 
 friends, who came to see him, naturally made concern- 
 ing the state of his health. The conversation which 
 I mentioned above, and which passed on Thursday 
 the eighth of August, was the last, except one, that I 
 ever had with him. He had now become so very 
 weak, that the company of his most intimate friends 
 fatigued him ; for his cheerfulness was still so great, 
 his complaisance and social disposition were still so 
 entire, that when any friend was with him, he could 
 not help talking more, and with greater exertion, than 
 
Kxii LETTER FROM ADAM SMITH, 
 
 suited the weakness of his body. At his own desire, 
 therefore, I agreed to leave Edinburgh, where I was 
 staying partly upon his account and returned to my 
 mother's house here at Kirkaldy, upon condition that 
 he would send for me whenever he wished to see me ; 
 the physician who saw him most frequently. Dr. Black, 
 undertaking, in the mean time, to write me occasion- 
 ally an account of the state of his health. 
 
 On the twenty-second of August, the doctor v*^rote 
 me the following letter : — 
 
 ** Since my last, Mr. Hume has passed his time 
 pretty easily, but is much weaker. He sits up, goes 
 down stairs once a day, and amuses himself with 
 reading, but seldom sees any body. He finds that 
 even the conversation of his most intimate friends 
 fatigues and oppresses him ; and it is happy that he 
 does not need it, for he is quite free from anxiety, im- 
 patience, or low spirits, and passes his time very well 
 with the assistance of amusing books." 
 
 I received, the day after, a letter from Mr. Hume 
 himself, of which the following is an extract : — 
 
 '* Edinburgh, 23d August, 1776. 
 
 **My Dearest Friend, 
 
 ''I am obliged to make use of my nephew's hand 
 
 in writing to you, as I do not rise to-day. 
 
 * * 
 
 '*I go very fast to decline, and last night had a 
 
 small fever, which I hoped might put a quicker period 
 
LETTER FROM ADAM SMITH. xxiii 
 
 to this tedious illness ; but unluckily it has, in a great 
 measure, gone off. I cannot submit to your coming 
 over here on my account, as it is possible for me to 
 see you so small a part of the day ; but Dr. Black can 
 better inform you concerning the degree of strength 
 which may from time to time remain with me. Adieu, 
 etc.*' 
 
 Three days after, I received the following iettet 
 from Dr. Black : — 
 
 "Edinburgh, Monday, 26th August, 1776, 
 ''Dear Sir, 
 
 ** Yesterday, about four o'clock, afternoon, Mr. 
 Hume expired. The near approach of his death be- 
 came evident in the night between Thursday and Fri- 
 day, when his disease became excessive, and soon 
 weakened him so much, that he could no longer rise 
 out of his bed. He continued to the last perfectly 
 sensible, and free from much pain or feelings of dis- 
 tress. He never dropped the smallest expression of 
 impatience; but when he had occasion to speak to 
 the people about him, always did it with affection and 
 tenderness. I thought it improper to write to bring 
 you over, especially as I heard that he had dictated a 
 letter to you, desiring you not to come. When he 
 became very weak, it cost him an effort to speak; 
 and he died in such a happy composure of mind, that 
 nothing could exceed it," 
 
xxiv LETTER FROM ADAM SMITH. 
 
 Thus died our most excellent and never to be for- 
 gotten friend ; concerning whose philosophical opin- 
 ions men will, no doubt, judge variously, every one 
 approving or condemning them, according as they 
 happen to coincide or disagree with his own, but con- 
 cerning whose character and conduct there can scarce 
 be a difference of opinion. His temper, indeed, 
 seemed to be more happily balanced, if I may be al- 
 lowed such an expression, than that perhaps of any 
 other man I have ever known. Even in the lowest 
 state of his fortune, his great and necessary frugality 
 never hindered him from exercising, upon proper oc- 
 casions, acts both of charity and generosity. It was 
 a frugality founded not upon avarice, but upon the 
 love of independency. The extreme gentleness of his 
 nature never weakened either the firmness of his mind 
 or the steadiness of his resolutions. His constant 
 pleasantry was the genuine effusion of good nature and 
 good humour, tempered with delicacy and modesty, 
 and without even the slightest tincture of malignity, 
 so frequently the disagreeable source of what is called 
 wit in other men. It never was the meaning of his 
 raillery to mortify ; and therefore, far from offending, 
 it seldom failed to please and delight, even those who 
 were frequently the objects of it ; there was not per- 
 haps any one of all his great and amiable qualities 
 which contributed more to endear his conversation. 
 And that gayety of temper, so agreeable in society, 
 but which is so often accompanied with frivolous and 
 
LETTER FROM ADAM SMTTH. xxv 
 
 superficial qualities, was in him certainly attended 
 with the most severe application, the most extensive 
 learning, the greatest depth of thought, and a capacity 
 in every respect the most comprehensive. Upon the 
 whole, I have always considered him, both in his life- 
 time and since his death, as approaching as nearly to 
 the idea of a perfectly wise and virtuous man as per- 
 haps the nature of human frailty will permit. 
 
 I ever am, dear sir. 
 
 Most affectionally yours, 
 
 » Adam Smith. 
 
CONTENTS. 
 
 PAGB 
 
 Publishers' Preface iii 
 
 * Autobiography v 
 
 Letter from Adam Smith to William Strahan .... xvii 
 
 Author's Advertisement xxviii 
 
 An Enquiry Concerning Human Understanding — 
 
 Of the Different Species of Philosophy (h 
 
 ».| - Of the Origin of Ideas u^ 
 
 — f— ' Of the Association of Ideas Cou 
 
 t- Sceptical Doubts Concerning the Operations of the 
 
 Understanding , 
 
 -r Sceptical Solution of these Doubts (^m^ 
 
 •♦ Of Probability 57 
 
 ■4"^ Of the Idea of Necessary Connexion 61^ ^ 
 
 Of Liberty and Necessity S^ 
 
 Of the Reason of Animals 109 
 
 — Of Miracles 114 
 
 — — - Of a Particular Providence and of a Future State . . 139 
 
 Of the Academical or Sceptical Philosophy .... 158 
 Selections from A Treatise of Human Nature — 
 The Doctrine of Causalityo 
 Book I. Part III. 
 
 Section I. Of Knowledge 185 
 
 . X Section II. Of Probability; and of the Idea of Cause 
 
 and Effect 190 
 
 Section III. Why a Cause Is Always Necessary . . 197 
 
 -^ Section XIV. Of the Idea of Necessary Connexion . . 202 vV 
 The Doctrine of Substance. 
 Book I. Part I. 
 
 Section VI. Of Modes and Substances 22T 
 
 Book I. Part II. 
 -f- Section VI. Of the Idea of Existence and of External 
 
 Existence 229 ^ 
 
 Book I. Part IV. 
 
 ^ Section II, Of Scepticism with regard to the Senses 232 ^ 
 
 < Section VI. Of Personal Identity 245 ^^ 
 
 t Appekdix 260 
 
 I 
 I 
 
AUTHOR'S ADVERTISEMENT. 
 
 Most of the principles, and reasonings, contained in this vol- 
 ume,* were published in a work in three volumes, called A Trea- 
 tise of Human Nature: A work which the Author had projected 
 before he left College, and which he wrote and published not long 
 after. But not finding it successful, he was sensible of his error 
 in going to the press too early, and he cast the whole anew in the 
 following pieces, where some negligences in his former reasoning 
 and more in the expression, are, he hopes, corrected. Yet several 
 writers who have honoured the Author's Philosophy with answers, 
 have taken care to direct all their batteries against that juvenile 
 work, which the author never acknowledged, and have affected to 
 triumph in any advantages, which, they imagined, they had ob- 
 tained over it : A practice very contrary to all rules of candour 
 and fair-dealing, and a strong instance of those polemical artifices 
 which a bigotted zeal thinks itself authorized to employ. Hence- 
 forth, the Author desires, that the following Pieces may alone be 
 regarded as containing his philosophical sentiments and principles 
 
 IVolume II. of the posthumous edition of Hume's works published in 
 1777 and containing, besides the present Enquiry, A Dissertation on the Pas 
 sions, and An Enquiry Concerning the Principles of Morals. A reprint of the 
 latter treatise has already appeared in the Religion of Science Library (No. 
 46), published by The Open Court Publishing Qo.— Editor. 
 
rt 
 
 SECTION I. 
 
 OF THE DIFFERENT SPECIES OF PHILOSOPHY. 
 
 MORAL philosophy, or the science of human na- 
 ture, may be treated after two different manners; 
 each of which has its peculiar merit, and may contrib- 
 ute to the entertainment, instruction, and reformation 
 of mankind. The one considers man chiefly as born Tt 
 for action; and as influenced in his measures by taste ^^ 
 and sentiment; pursuing one object, and avoiding 
 another, according to the valueywhich these objects 
 seem to possess, and according to the light in which 
 they present themselves. As virtue, of all objects, is 
 allowed to be the most valuable, this species of philos- 
 ophers paint her in the most amiable colours ; borrow- 
 ing all helps from poetry and eloquence, and treating 
 their subject in an easy and obvious manner, and such 
 as is best fitted to please the imagination, and engage 
 the affections. They select the most striking observa- 
 tions and instances from common life ; place opposite 
 characters in a proper contrast ; and alluring us into 
 the paths of virtue by the views of glory and happi- 
 ness, direct our steps in these paths by the soundest 
 precepts and most illustrious examples. They make 
 us feel^XSxQ difference between vice and virtue ; they 
 excite and regulate our sentiments ; and so they can 
 but bend our hearts to the love of probity and true 
 honour, they think, that they have fully attained the 
 end of all their labours. 
 
2 AN ENQUIRY CONCERNING 
 
 The other species of philosophers jconsider man v 
 the light of a reasonable rather than an active being,^ 
 and endeavour to form his understanding mor^; than 
 cultivate his manners. They regard human nature as 
 a subject of speculation ; and with a narrow scrutiny 
 examine it, in order to find those principles, which 
 regulate our understanding, excite our sentiments, and 
 make us to approve or blame any particular object, 
 action, or behaviour. They think it a reproach to all 
 literature, that philosophy should not yet have fixed, 
 beyond controversy, the foundation of morals, reason- 
 ing, and criticism ; and should for ever talk of truth 
 and falsehood, vice and virtue, beauty and deformity, 
 without being able to determine the source of these 
 distinctions. While they attempt this arduous task, 
 they are deterred by no difficulties ; but proceeding 
 from particular instances to general principles, they 
 still push on their enquiries to principles more gen- 
 eral, and rest not satisfied till they arrive at those or- 
 iginal principles, by which, in every science, all human 
 curiosity must be bounded. Though their speculations 
 seem abstract, and even unintelligible to common read- 
 ers, they aim at the approbation of the learned and the 
 wise; and think themselves sufficiently compensated 
 for the labour of their whole lives, if they can discover 
 some hidden truths, which may contribute to the in- 
 struction of posterity. 
 
 It is certain that the easy and obvious philosophy 
 will always, with the generality of mankind, have the 
 preference above the accurate and abstruse ; «ind by 
 many will be recommended, not only as more agree- 
 able, but more useful than the other. It enters more 
 into common life; moulds the heart and affection's; 
 and, by touching those principles which actuate men, 
 
HUMAN UNDERSTANDING. 3 
 
 reforms their conduct, and brings them nearer to that 
 model of perfection which it describes. On the con- 
 trary, the abstruse philosophy, being founded on a 
 turn of mind, which cannot enter into business and 
 action, vanishes when the philosopher leaves the shade, 
 and comes into open day ; nor can its principles easily 
 retain any influence over our conduct and behaviour. 
 The feelings of our heart, the agitation of our passions, 
 the vehemence of our affections, dissipate all its con- 
 clusions, and reduce the profound philosopher to a 
 mere plebeian. 
 
 This also must be confessed, that the most dur- 
 able, as well as justest fame, has been acquired by the 
 easy philosophy, and that abstract reasoners seem 
 hitherto to have enjoyed only a momentary reputation, 
 from the caprice or ignorance of their own age, but 
 have not been able to support their renown with more 
 equitable posterity. It is easy for a profound philos- 
 opher to commit a mistake in his subtile reasonings; 
 and one mistake is the necessary parent of another, 
 while he pushes on his consequences, and is not de- 
 terred from embracing any conclusion, by its unusual 
 j appearance, or its contradiction to popular opinion. 
 I But a philosopher, who purposes only to represent the 
 ' common sense of mankind in more beautiful and more 
 I engaging colours, if by accident he falls into error, 
 i goes no farther; but renewing his appeal to common 
 I sense, and the natural sentiments of the mind, returns 
 into the right path, and secures himself from any dan- 
 gerous illusions. The fame of Cicero flourishes at 
 present; but that of Aristotle is utterly decayed. La 
 Bruy^re passes the seas, and still maintains his repu- 
 tation : But the glory of Malebranche is confined to 
 his 0W41 nation, and to his own age. And Addison, 
 
 ,/ 
 
4 AN ENQ UIR V CONCERNING 
 
 perhaps, will be read with pleasure, when Locke shaL' 
 be entirely forgotten. 
 
 The mere philosopher is a character, which is com- 
 monly but little acceptable in the world, as being sup- 
 posed to contribute nothing either to the advantage 
 or pleasure of society ; while he lives remote from 
 communication with mankind, and is wrapped up in 
 principles and notions equally remote from their com- 
 prehension.^ On the other hand, the mere ignorant is 
 still more despised ; nor is any thing deemed a surer 
 sign of an illiberal genius in an age and nation where 
 the sciences flourish, than to be entirely destitute of 
 all relish for those noble entertainments. The most 
 perfect character is supposed to lie between those ex- 
 tremes ; retaining an equal ability and taste for books, 
 company, and business ; preserving in conversation 
 that discernment and delicacy which arise from polite 
 letters; and in business, that probity and accuracy 
 which are the natural result of a just philosophy. In 
 order to diffuse and cultivate so accomplished a char- 
 acter, nothing can be more useful than compositions 
 of the easy style and manner, which draw not too 
 much from life, require no deep application or retreat 
 to be comprehended, and send back the student among 
 mankind full of noble sentiments and wise precepts, 
 applicable to every exigence of human life. By mean.s 
 of such compositions, virtue becomes amiable, science 
 agreeable, company instructive, and retirement enter- 
 taining. 
 
 I Man is a reasonable being ; and as such, receives 
 from science his proper food and nourishment : But 
 so narrow are the bounds of human understanding, 
 that little satisfaction can be hoped for in this partic- 
 ular, either from the extent or security of his acquisi- 
 
HUMAN UNDERSTANDING, 5 
 
 tions. Man is a sociable, no less than a reasonable 
 being : But neither can he always enjoy company 
 agreeable and amusing, or preserve the proper relish 
 for them. Man is also an active bein^ ; and from 
 that disposition, as well as from the various necessities 
 of human life, must submit to business and occupa- 
 tion : But the mind requires some relaxation, and can- 
 not always support its bent to care and industry. It \ 
 seems, then, that nature has pointed out a mixed kind \ *^ 
 of life as most suitable to the human race, and secretly ; 
 admonished them to allow none of these biasses to ; 
 draw too much, so as to incapacitate them for other 
 occupations and entertainments. Indulge your passion . 
 for science, says she, but let your science be human, | 
 and such as may have a direct reference to action and i 
 society. Abstruse thought and profound researches I 
 prohibit, and will severely punish, by the pensive mel- 
 ancholy which they introduce, by the endless uncer- 
 tainty in which they involve you, and by the cold re- 
 ception which your pretended discoveries shall meet 
 with, when communicated. JBe a philosopher; but, 1 
 amidst all your philosophy, be still a man^^ ' 
 
 Were the generality of mankind contented to pre- 
 fer the easy philosophy to the abstract and profound, 
 without throwing any blame or contempt on the latter, 
 it might not be improper, perhaps, to comply with this 
 general opinion, and allow every man to enjoy, with- 
 out opposition, his own taste and sentiment. But as 
 the matter is often carried farther, even to the absolute 
 rejecting of all profound reasonings, or what is com- 
 monly called metaphysics^ we shall now proceed to con- 
 sider what can reasonably be pleaded in their behalf. 
 I We may begin with observing, that one consider- 
 able advantage, which results from the accurate and 
 
e AN ENQUIRY CONCERNING 
 
 ] abstract philosophy, is, its subserviency to the easy 
 and humane, which, without the former, can never 
 
 I attain a sufficient degree of exactness in its sentiments, 
 precepts, or reasoning^ All polite letters are nothing 
 but pictures of human life in various attitudes and 
 situations ; and inspire us with different sentiments, 
 of praise or blame, admiration or ridicule, according 
 to the qualities of the object, which they set before 
 us. An artist must be better qualified to succeed in 
 this undertaking, who, besides a delicate taste and a 
 quick apprehension, possesses an accurate knowledge 
 of the internal fabric, the operations of the under- 
 standing, the workings of the passions, and the various 
 species of sentiment which discriminate vice and vir- 
 tue. How painful soever this inward search or en- 
 quiry may appear, it becomes, in some measure, re- 
 quisite to those, who would describe with success the 
 obvious and outward appearances of life and manners. 
 The anatomist presents to the eye the most hideous 
 and disagreeable objects ; but his science is useful to 
 the painter in delineating even a Venus or an Helen. 
 While the latter employs all the richest colours of his 
 art, and gives his figures the most graceful and en- 
 gaging airs ; he must still carry his attention to the 
 inward structure of the human body, the position of 
 the muscles, the fabric of the bones, and the use and 
 figure of every part or organ. (.Accuracy is, in every 
 
 f case, advantageous to beauty, and just reasoning to 
 delicate sentiment. In vain would we exalt the one 
 f by depreciating the otherTy 
 
 Besides, we may obs'erve, in every art or profes- 
 sion, even those which most concern life or action, 
 that a spirit of accuracy, however acquired, carries all 
 of them nearer their perfection, and renders them^ 
 
HUMAN UNDERSTANDING. 7 
 
 more subservient to the interests of society. And 
 though a philosopher may live remote from business, 
 the genius of philosophy, if carefully cultivated by sev- 
 eral, must gradually diffuse itself throughout the whole 
 society, and bestow a similar correctness on every 
 art and calling. The politician will acquire greater 
 foresight and subtility, in the subdividing and balanc- 
 ing of power ; the lawyer more method and finer prin- 
 ciples in his reasonings ; and the general more regular- 
 ity in his discipline, and more caution in his plans 
 and operations. The stability of modern governments 
 above the ancient, and the accuracy of modern philos- 
 ophy, have improved, and probably will still improve, 
 by similar gradations. 
 
 Were there no advantage to be reaped from these 
 studies, beyond the gratification of an innocent curios- 
 ity, yet ought not even this to be despised ; as being 
 one accession to those few safe and harmless pleasures, 
 which are bestowed on the human race./Jhe sweetest 
 and most inoffensive path of life leads through the 
 avenues of science and learning ;^ and Avhoever^an 
 either remove any obstructions in this way, or open 
 up any new prospect, ought so far to'be esteemed a 
 benefactor to mankind^And though these researches 
 may appear painful and fatiguing, it is with some 
 minds as with some bodies, which being endowed with 
 vigorous and florid health, require severe exercise, 
 and reap a pleasure from what, to the generality of 
 mankind, may seem burdensome and laborious. Ob- 
 scurity, indeed, is painful to the mind as well as to the 
 eye ; but to bring light from obscurity, by whatever 
 labour, must needs be delightful and rejoicing. 
 
 But this obscurity in the profound and abstract 
 philosophy, is objected to, not only as painful and 
 
\ 
 
 g AN ENQUIRY CONCERNING 
 
 fatiguing, but as the inevitable source of uncertainty 
 and error. Here indeed lies the justest and most 
 plausible objection against a considerable part of meta- 
 /physics, that they are not properly a science ; but arise 
 either from the fruitless efforts of human vanity, which 
 would penetrate into subjects utterly inaccessible to 
 the understanding, or from the craft of popular super- 
 stitions, which, being unable to defend themselves on 
 fair ground, raise these intangling brambles to cover 
 and protect their weakness. Chaced from the open 
 country, these robbers fly into the forest, and lie in 
 wait to break in upon every unguarded avenue of the 
 mind, and overwhelm it with religious fears and pre- 
 judices. The stoutest antagonist, if he remit his watch 
 a moment, is oppressed. And many, through cow- 
 ardice and folly, open the gates to the enecnies, and 
 willingly receive them with reverence and submission, 
 as their legal sovereigns. 
 
 But is this a sufficient reason, why philosophers 
 should desist from such researches, and leave super- 
 stition still in possession of her retreat? Is it not 
 proper to draw an opposite conclusion, and perceive 
 the necessity of carrying the war into the most secret 
 recesses of the enemy? In vain do we hope, that men, 
 from frequent disappointment, will at last abandon 
 such airy sciences, and discover the proper province 
 of human reason. For, besides, that many persons 
 find too sensible an interest in perpetually recalling 
 such topics ; besides this, I say, the motive of blind 
 despair can never reasonably have place in the sci- 
 ences; since, however unsuccessful former attempts 
 may have proved, there is still room to hope, that the 
 industry, good fortune, or improved sagacity of suc- 
 ceeding generations may reach discoveries unknown 
 
HUMAN UNDERSTANDING. 9 
 
 to former ages. Each adventurous genius will leap at 
 the arduous prize, and find himself stimulated, rather 
 than discouraged, by the failures of his predecessors ; 
 while he hopes that the glory of achieying so hard an 
 adventure is reserved for him alone./OPhe only methd^ 
 of freeing learning, at once, from these abstruse quesA ^^ 
 tions, is to enquire seriously into the nature of human J 
 understanding, and show, from an exact analysis of | 
 its powers and capacity, that it is by no means fitted 1 
 for such remote and abstruse subjects. We must sub- yo 
 mit to this fatigue, in order to live at ease ever after : \ 
 And must cultivate true metaphy si cs with some care , \ ,^J^^ 
 in order to destroy the false and adulteratey^ Indo^i/ / 
 lence, which, to some persons, affords a safeguard 
 against this deceitful philosophy, is, with others, over- 
 balanced by curiosity ; and despair, which, at some 
 moments, prevails, may give place afterwards to san- 
 guine hopes and expectations. XAccurate and just rea- 
 soning is the only catholic remedy, fitted for all per- 
 sons and all dispositions f7and is alone able to subvert 
 that abstruse philosopKy and metaphysical jargon, 
 which, being mixed up with popular superstition, ren- 
 ders it in a manner impenetrable to careless reasoners, 
 and gives it the air of science and wisdom. 
 
 Besides this advantage of rejecting, after deliberate 
 enquiry, the most uncertain and disagreeable part of 
 learning, there are many positive advantages, which 
 result from an accurate scrutiny into the powers and 
 faculties of human nature. It is remarkable concern-/^ 
 ing the operations of the mind, that, though most in- 
 timately present to us, yet, whenever they become the 
 object of reflexion, they seem involved in obscurity ; 
 nor can the eye readily find those lines and boundaries, 
 w^iich discriminate and distinguish them. The objects 
 
I 
 
 xo AN ENQUIRY CONCERNING 
 
 are too fine to remain long in the same aspect or situa- 
 tion ; and must be apprehended in an instant, by a 
 superior penetration, derived from nature, and im- 
 proved by habit and reflexion. It becomes, therefore, 
 no inconsiderable part of science barely to know the 
 different operations of the mind, to separate them from 
 each other, to class them under their proper heads, 
 and to correct all that seeming disorder, in which they 
 lie involved, when made the object of reflexion and en- 
 quiry. This talk of ordering and distinguishing, which 
 has no merit, when performed with regard to external 
 bodies, the objects of our senses, rises in its value, 
 when directed towards the operations of the mind, in 
 proportion to the difficulty and labour, which we meet 
 with in performing it. And if we can go no farther 
 than this mental geography, or delineation of the dis- 
 tinct parts and powers of the mind, it is at least a 
 satisfaction to go so far ; and the more obvious this 
 science may appear (and it is by no means obvious) 
 the more contemptible still must the ignorance of it 
 be esteemed, in all pretenders to learning and philos- 
 ophy. 
 
 Nor can there remain any suspicion, that this sci- 
 ence is uncertain and chimerical ; unless we should 
 entertain such a scepticism as is entirely subversive of 
 all speculation, and even action./j.t cannot be doubted, 
 ;\that the mind is endowed with several powers and 
 faculties, that these powers are distinct from each 
 other, that what is really distinct to the immediate 
 [. perception may be distinguished by reflexion; and 
 / consequently, that there is a truth and falsehood in 
 \ all propositions on this subject, and a truth and false- 
 I (hood, which lie, not beyond the compass of human 
 ^^understanding. / There are many obvious distinctions 
 
HUMAN UNDERSTANDING. ix 
 
 of this kind, such as those between the will and un- 
 derstanding, the imagination and passions, which fall 
 within the comprehension of every human creature ; 
 and the finer and more philosophical distinctions are 
 no less real and certain, though more difficult to be 
 comprehended. Some instances, especially late ones, 
 of success in these enquiries, may give us a juster no- 
 tion of the certainty and solidity of this branch of 
 learning. And shall we esteem it worthy the labour 
 of a philosopher to give us a true system of the plan- 
 ets, and adjust the position and order of those remote 
 bodies ; while we affect to overlook those, who, with 
 so much success, delineate the parts of the mind, in 
 which we are so intimately concerned ? 
 
 But may we not hope, that philosophy, if culti- 
 vated with care,^ and encouraged by the attention of 
 the public, may carry its researches still farther^ and 
 discover, at least in some degree, the secret springs 
 and principles, by which the human mind is actuated 
 in its operations ? Astronomers had long contented 
 themselves with proving, from the phaenomena, the 
 true motions, order, and magnitude of the heavenly 
 bodies : Till a philosopher, at last, arose, who seems, 
 from the happiest reasoning, to have also determined 
 the laws and forces, by which the revolutions of the 
 planets are governed and directed. The like has been 
 performed with regard to other parts of nature. And 
 there is no reason to despair of equal success in our 
 enquiries concerning the mental powers and economy, 
 if prosecuted with equal capacity and caution. It is 
 probable, that one operation and principle of the mind 
 depends on another; which, again, may be resolved 
 into one more general and universal : And how far 
 these researches may possibly be carried, it will be 
 
la AN ENQUIRY CONCERNING 
 
 difficult for us, before, or even after, a careful trial, 
 exactly to determine. This is certain, that attempts 
 fof this kind are every day made even by tliose who 
 philosophize the most negligently : And nothing can 
 be more .requisite than to enter upon the enterprize 
 with thorough care and attention ; that, if it lie within 
 the compass of human understanding, it may at last 
 be happily achieved ; if not, it may, however, be re- 
 jected with some confidence and security. This last 
 conclusion, surely, is not desirable ; nor ought it to be 
 embraced too rashly. For how much must we dimin- 
 ish from the beauty and value of this species of phi- 
 losophy, upon such a supposition? Moralists ha\'e 
 hitherto been accustomed, when they considered the 
 vast multitude and diversity of those actions that ex- 
 cite our approbation or dislike, to search for some 
 common principle, on which this variety of sentiments 
 might depend. And though they have sometimes car- 
 ried the matter too far, by their passion for some one 
 general principle ; it must, however, be confessed, 
 that they are excusable in expecting to find some gen- 
 eral principles, into which all the vices and virtues 
 were justly to be resolved. The like has been the 
 endeavour of critics, logicians, and even politicians : 
 Nor have their attempts been wholly unsuccessful; 
 though perhaps longer time, greater accuracy, and 
 more ardent application may bring these sciences still 
 nearer their perfection. To throw up at once all pre- 
 tensions of this kind may justly be deemed more rash, 
 precipitate, and dogmatical, than even the boldest and 
 most affirmative philosophy, that has ever attempted 
 to impose its crude dictates and principles on man- 
 kind. 
 
 What though these reasonings concerning human 
 
HUMAN UNDERSTANDING, 13 
 
 nature seem abstract, and of difficult comprehension ? 
 This affords no presumption of their falsehood. On 
 the contrary, it seems impossible, that what has hith- 
 erto escaped so many wise and profound philosophers 
 can be very obvious and easy. And whatever pains 
 these researches may cost us, we may think ourselves 
 sufficiently rewarded, not only in point of profit but of 
 pleasure, if, by that means, we can make any addition 
 to our stock of knowledge, in subjects of such un- 
 speakable importance. 
 
 But as, after all, the abstractedness of these specu- 
 lations is no recommendation, but rather a disadvan- 
 tage to them, and as this difficulty may perhaps be 
 surmounted by care and art, and the avoiding of all 
 unnecessary detail, we have, in the following enquiry, 
 attempted to throw some light upon subjects, from 
 which uncertainty has hitherto deterred the wise, and 
 obscurity the ignorant.^ Happy, if we can unite the , 
 boundaries of the differeijt species of philosophy, by^^ 
 reconciling profound enquiry with clearness, and truth 
 with novelty ! And still more happy, if reasoning in 
 this easy manner, we can undermine the foundations 
 of an abstruse philosophy, which seems to have hith- 
 erto served only as a shelter to superstition, and a 
 cover to absurdity and error I 
 
t 
 
 i 
 
 G 
 
 SECTION II. 
 
 XOP THE ORIGIN OF IDEAS. 
 
 EVERY one will readily allow, that there is a con- 
 siderable difference between the perce ptions of 
 the mind, when a man feels the pain of excessive heat, 
 or the pleasure of moderate warmth, and when he aft- 
 erwards recalls to his memory this sensation, or antic- 
 ipates it by his imagination^ These faculties may 
 mimic or copy the perceptions of the senses ; but they 
 never can entirely reach the force and vivacity of the 
 original sentiment. The utmost we say of them, even 
 when they operate with greatest vigour, is, that they 
 represent their object in so lively a manner, that we 
 could almost say we feel or see it : But, except the 
 mind be disordered by disease or madness, they never 
 can arrive at such a pitch of vivacity, as to render 
 these perceptions altogether undistinguishable. All 
 the colours of poetry, however splendid, can never 
 paint natural objects in such a manner as to make the 
 description be taken for a real landskip. _The most 
 lively thought is still inferior to the dullest sensation.J 
 
 We may observe a like distinction to run through 
 all the other perceptions of the mind. A man in a fi. 
 of anger, is actuated in a very different manner from 
 one who only thinks of that emotion. If you tell me, 
 that any person is in love, I easily understand your 
 meaning, and form a just conception of his situation ; 
 but never can mistake that conception for the real 
 
HUMAN UNDERSTANDING. 15 
 
 disorders and agitations of the passion. ' When we 
 reflect on our past sentiments and affections, our 
 thought is a faithful mirror, and copies its objects 
 truly ; but the colours which it employs are faint and 
 dull, in comparison of those in which our original per- 
 ceptions were clothed. It requires no nice discern- 
 ment or metaphysical head to mark the distinction be- 
 tween themry 
 
 Here therefore we may divide all the perceptions 
 of the mind into two classes or species, which are dis- 
 tingu^hed by their different degrees of force and vivac- 
 ity, rjhe less f orcib le and lively are commonly de- 
 nominated Thoughts ox IdecuQ'TYie other species want 1 
 a name in our language, and in most others ; I sup- 
 pose, because it was not requisite for any, but philos- 
 ophical purpose^ to rank them under a general term 
 or appellation.^Let us, therefore, use a little freedom, 
 and call them Im^resswnsJ? employing that word in a [[ 
 sense somewhat differenTTrom the usual.J^y the term 1\ 
 impression, then, I mean all our more lively percep- II 
 tions, when we hear, or see, or feel, or love, or hate, V 
 or desire, or will. /And impressions are distinguishe^^^ 
 from ideas, whicli are the less lively perceptions, of 
 which we are conscious, when we reflect on ajjy of 
 those sensations or movements above mentioned.! 
 
 Nothing, at first view, may seem more unbounded 
 than the thought of man, which not only escapes all 
 human power and authority, but is not even restrained 
 within the limits of nature and reality. To form mon- 
 sters, and join incongruous shapes and appearances, 
 costs the imagination no more troubie than to conceive 
 the most natural and familiar objects. And while the 
 body is confined to one planet, along which it creeps 
 with pain and difficulty ; the thought can in an instant 
 
i6 AN ENQUIRY CONCERNING 
 
 transport us into the most distant regions of the uni- 
 verse ; or even beyond the universe, into the un- 
 bounded chaos, where nature is supposed to lie in total 
 confusion. What never was seen, or heard of, may 
 yet be conceived ; nor is any thing beyond the power 
 of thought, except what implies an absolute contra- 
 diction. 
 
 «-^ But though our thought seems to possess this un- 
 
 ! . bounded liberty, we shall find, upon a nearer examina- 
 tion, that it is really confined within very narrow lim- 
 its, and that all this creative power of the mind 
 j amounts to no more than the faculty of compounding 
 
 tC^ i transposing, augmenting, or diminishing the materials 
 afforded us by the senses and experience.' When we 
 think of a golden mountain, we only join two consist- 
 ent ideas, gold, and mountain, with which we were 
 formerly acquainted. A virtuous horse we can con- 
 ceive ; because, from our own feeling, we can conceive 
 virtue ; and this we may unite to the figure and shape 
 of a horse, which is an animal familiar to us.j In short, 
 all the materials of thinking are derived either from 
 our outward or inward sentiment : the mixture and 
 composition of these belongs alone to the mind and 
 will. Or, to express myself in philosophical language, 
 all our ideas i^or more feeble perceptions jare copies of 
 our impressions(or more lively ones.Jj 
 ■^ To prove this, the two following arguments wil], 
 I hope, be sufficient./. First, when we analyze our 
 thoughts or ideas, however compounded or sublime, 
 
 y^ we always find that they resolve themselves into such 
 simple ideas as were copied from a precedent feeling 
 or sentimen^ Even those ideas, which, at first view, 
 seem the most wide of this origin, are fojund, upon a 
 nearer scrutiny, to be derived from it. / The idea of 
 
HUMAN UNDERSTANDING. 17 
 
 God, as meaning an infinitely intelligent, wise, and 
 good Being, arises from reflecting on the operations of 
 our own mind, and augmenting, without limit, those a 
 qualities of goodness and wisdom.'7We may prosecute ^ 
 this enquiry to what length we please ; where we shall 
 always find, that every idea which we examine is copied 
 from a similar impression/T Those who would assert 
 that this position is not universally true nor without 
 exception, have only one, and that an easy method of 
 refuting it ; by producing that idea, which, in their 
 opinion, is not derived from this source. It will then 
 be incumbent on us, if we would maintain our doc- 
 trine, to produce the impression, or lively perception, 
 which correspon^is to it. 
 
 Secondly. ]\i it happen, from a d efect of the or- 
 gan, th at a man is not susceptible of any species of '^ 
 sensation,^ we always find tha t he is as little suscept- 
 ible of the correspondent ideas J A blind man can form 
 no notion of colours; a deaf man of sounds. Restore 
 either of them that sense in which he is deficient ; by 
 opening this new inlet for his sensations, you also 
 open an inlet for the ideas ; and he finds no difficulty 
 in conceiving these objects. J The case is the same, if 
 the object, proper for excitilig any sensation, has never 
 been applied to the organ. A Laplander or Negro 
 has no notion of the relish of wine. And though there 
 are few or no instances of a like deficiency in the^ 
 mind, where a person has never felt or is wholly in- 
 capable of a sentiment or passion that belongs to his 
 species; yet we find the same observation to take place 
 in a less degree. A man of mild manners can form no 
 idea of inveterate revenge or cruelty ; nor can a selfish 
 heart easily conceive the heights of friendship and 
 generosity. It is readily allowed, that other beings 
 
 ■R 
 
i8 AN ENQUIRY CONCERNING 
 
 may possess many senses of which we can have no 
 
 conception ; because the ideas of them have never 
 
 , been introduced to us in the only manner by which an 
 
 (i idea can have access to the mind, to wit, by the actual 
 I feeling and sensati on.^ 
 
 There is, however, one contradictory phenomenon, 
 which may prove that it is not absolutely impossible 
 for ideas to arise, independent of their correspondent 
 impressions. I believe it will readily be allowed, that 
 the several distinct ideas of colour, which enter by the 
 eye, or those of sound, which are conveyed by the ear, 
 are really different from each other ; though, at the 
 same time, resembling. Now if this be true of differ- 
 ent colours, it must be no less so of the different 
 shades of the same colour ; and each shade produces 
 a distinct idea, independent of the rest. For if this 
 should be denied, it is possible, by the continual gra- 
 dation of shades, to run a colour insensibly into what 
 is most remote from it; and if you will not allow any 
 of the means to be different, you cannot, without ab- 
 surdity, deny the extremes to be the same. Suppose, 
 therefore, a person to have enjoyed his sight for thirty 
 years, and to have become perfectly acquainted with 
 colours of all kinds except one particular shade of 
 blue, for instance, which it never has been his fortune 
 to meet with. Let all the different shades of that 
 colour, except that single one, be placed before him, 
 descending gradually from*the deepest to the lightest; 
 it is plain that he will perceive a blank, where that 
 shade is wanting, and will be sensible that there is a 
 greater distance in that place between the contiguous 
 colours than in any other. Now I ask, whether it be 
 possible for him, from his own imagination, to supply 
 ^ this deficiency, and raise up to himself the idea of that 
 
HUMAN UNDERSTANDING. 19 
 
 particular shade, though it had never been conveyed )^ 
 
 to him by his senses? I believe there are few but will ^v^ - 
 be of opinion that he can: and this may serve as a ^^ 
 
 prnnfjjhat J:h«^ t;imp1f^ j'^'^rliS R^*^ ^'^^ alw^nygj in eVCry ^/^ 
 
 instance, derived fro ni the correspondent impressioQ ^ ; 
 though this mstance is so singular, that it is scarcely 
 worth our observing, and does not merit that for it 
 alone we should alter our general maxim. 
 
 Here, therefore, is a proposition, which not only 
 seems, in itself, simple and intelligible; but, if a 
 proper use were made of it, might render every dis- 
 pute equally intelligible, and banish all that jargon, 
 which has so long taken possession of metaphysical 
 reasonings, and drawn disgrace upon them. /All ideas, 
 especially abstract ones, are naturally faint and ob- 
 scure : the mind has but a slender hold of them : they 
 are apt to be confounded with other resembling ideas J 
 and when we have often employed any term, though 
 without a distinct meaning, we are apt to imagine it 
 has a determinate idea annexed to it. On the con- 
 trary, all impressions, that is, all sensations, either 
 outward or inward, are strong and vivid : the limits 
 between them are more exactly determined : nor is it 
 easy to fall into any error or mistake with regard to 
 them. When we entertain, therefore, any suspicion" 
 that a philosophical term is employed without any 
 meaning or idea (as is but too frequent), we need but 
 enquire, from what impr^sion is that supposed idea 
 derived? Ai^d if it be impossible to assign any, this 
 will serve to confirm our suspicion.^ By bringing 
 
 lit is probable that no more was meant by those, who denied innate 
 ideas, than that all ideas were copies of our impressions; though it must be 
 confessed, that the terms, which they employed, were not chosen with such 
 caution, nor so exactly defined, as to prevent all mistakes about their doc- 
 trine. For what is meant by innate ? If innate be equivalent to natural, then 
 
20 AN ENQ UTR Y CONCERNING 
 
 ideas into so clear a light we may reasonably hope 
 to remove all dispute, which may arise, concerning 
 their nature and reality. 
 
 all the perceptions and ideas of the mind must be allowed to be innate or 
 natural, in whatever sense we take the latter word, whether in opposition to 
 what is uncommon, artificial, or miraculous. If by innate be meant, contem- 
 porary to our birth, the dispute seems to be frivolous ; nor is it worth while 
 to enquire at what time thinking begins, whether before, at, or after our 
 birth. Again, the word idea, seems to be commonly taken in a very loose 
 sense, by Locke and others; as standing for any of our perceptions, our sen- 
 sations and passions, as well as thoughts. Now in this sense, I should desire 
 to know, what can be meant by asserting, that self-love, or resentment of in- 
 juries, or the passion between the sexes is not innate ? 
 
 But admitting these terms, impressions and ideas, in the sense above ex 
 plained, and understanding hy.innaie, what is original or copied from no pre 
 cedent perception, then may we assert that all our impressions are innate 
 and our ideas not innate. 
 
 To be ingenuous, I must own it to be my opinion, that Locke was be 
 trayed into this question by the schoolmen, who, making use of undefined 
 terms, draw out their disputes to a tedious length, without ever touching the 
 point in question. A like ambiguity and circumlocution seem to run through 
 that philosopher's reasonings on this as well as most other subjects. 
 
/ 
 
 SECTION III. 
 
 >^ OF THE ASSOCIATION OF IDEAS. 
 
 IT is evident that /there is a principle of connexion j 
 between the different thoughts or ideas of the \i 
 mind, and that, in their appearance to the memory or \ 
 imagination, they introduce each other with a certain I $< 
 
 degree of method and regularity, jln our more serious ' ^^ 
 thinking or discourse this is so observable that any ^ 
 
 particular thought, which breaks in upon the regular . ^ 
 tract or chain of ideas, is immediately remarked and )^ .\^ 
 rejected.^ And even in our wildest and most wander- J^ 
 ing reveries, nay in our very dreams, we shall find, if 
 we reflect, that the imagination ran jiot altogether at 
 adventures, but that there was stillja^^nnexion up- 1 
 held among the different ideas, which succeeded each - 
 others Were the loosest and freest conversatio.n to be 
 transcribed, there would immediately "be. observed 
 something;^ which connected it^n ajl.its transitions. 
 Or where this is wanting, the person who broke the 
 thread of discourse might still inform you, that there 
 had secretly revolved in his mind a succession of 
 thought, which had gradually led him from the sub- 
 ject of conversation. Among different languages, even 
 where we cannot suspect the least connexion or com- 
 munication, it is found, that the words, expressive of 
 ideas, the most compounded, do yet nearly correspond 
 to each other : a certain proof that the simple ideas, 
 comprehended in the compound ones, were bound to- 
 
Al^ ENQUIRY CONCERNING 
 
 an 
 
 gether by some universal principle, which had 
 equal influence on all mankind. 
 
 Though it be too obvious to escape observation, 
 P^that different ideas are connected together ; /I do not 
 find that any philosopher has attempted to enumerate 
 or class all the principles of associatioja.; i a subject, 
 however, that seems worthy of curiosity .LTo me, there 
 appear to be only three principles of connexion among 
 ideas, Ti2.xii^\y\Resemblance^ Contiguity in time or place, 
 and Cause or Effect. \ 
 
 That these principles serve to connect ideas will 
 not, I believe, be much doubted. jA picture naturally 
 leads our thoughts to the original : ^ the mention of 
 one apartment in a building naturally introduces an 
 enquiry or discourse concerning the others :2 and if 
 we think of a wound, we can scarcely forbear reflect- 
 ing on the pain which follows it.^ But that this 
 enumeration is complete, and that there are no other 
 principles of association except these, may be difficult 
 to prove to the satisfaction of the reader, or even to a 
 man's own satisfaction. All we can do, in such cases, 
 is to run over several instances, and examine carefully 
 the principle which binds the different thoughts to 
 each other, never stopping till we render the principle 
 as general as possible.^ The more instances we exam- 
 ine, and the more care we employ, the more assurance 
 shall we acquire, that the enumeration, which we form 
 from the whole, is complete and entire. 
 
 1 Resemblance. 2 Contiguity. 3 Cause and effect. 
 
 4 For instance, Contrast or Contrariety is also a connexion among Ideas 
 but it may, perhaps, be considered as a mixture of Causation and Resem- 
 blance. Where two objects are contrary, the one destroys the other; that is, 
 the cause of its annihilation, and the idea of the annihilation of an object 
 implies the idea of its former existence. 
 
SECTION IV. 
 
 SCEPTICAL DOUBTS CONCERNING THE OPERATIONS 
 OF THE UNDERSTANDING. 
 
 Part I. 
 
 ALL the objects of human reason or enquiry may 
 . naturally be divided into two kinds, to wit, Rela^ 
 iions of Ideas y and Matters of Factl Of the first kind are 
 the sciences of Geometry, AlgeDra, and Arithmetic ; 
 and in short, every affirmation which is either intui- 
 tively or demonstratively certain. That the square of 
 the hypoihenusets equal to the squares of the two sides ^ is 
 a proposition which expresses a relation between these 
 figures. That three times five is equal to the half of 
 thirty^ expresses a relation between these nuipbers. 
 Propositions of this kind are discoverable by the mere 
 operation of thought, without dependence on what is 
 anywhere existent in the univers^ Though there" 
 never were a circle or triangle in nature, the truths 
 demonstrated by Euclid would for ever retain their 
 certainty and evidence. v^.^ 
 
 Matters of fac t, which are the second objects of V 
 human Teason, are not ascertained in the same man- 
 ner ; nor is our evidence of their truth^ however great, \ > 
 of a like nature with the foregoingj The contrary of ^^^ S 
 every matter el iact is-StUl po^ssible; because it can 
 never imply a contradiction, and is conceived by the 
 mind with the samejac^ility. and distinctness, as if ever 
 
24 AN ENQUIRY CONCERNING 
 
 SO conformable to reality. That the sun will not rist 
 to-morrow is no less intelligible a proposition, and 
 implies no more contradiction than the affirmation, 
 that it will rise. We should in vain, therefore, attempt 
 to demonstrate its falsehood. ?Were it demonstratively 
 false, it would imply a contradiction, and could never 
 X be distinctly conceived by the mind. 
 
 It may, therefore, be a subject worthy of curiosity, 
 to enquire what is the nature of that evidence which 
 assures us Si any real existence and matter of fact, 
 beyond the present testimony of our senses, or the 
 \ records of our memory. | This part of philosophy, it 
 is observable, has been little cultivated, either by the 
 ancients or moderns ; and therefore our doubts and 
 errors, in the prosecution of so important an enquiry, 
 may be the more excusable ; while we march through 
 such difficult paths without any guide or direction. 
 They may even prove useful, by exciting curiosity, 
 and destroying that implicit faith and security, which 
 is the bane of all reasoning and free enquiry. The dis- 
 covery of defects in the common philosophy, if any 
 such there be, will not, I presume, be a discourage- 
 ment, but rather an incitement, as is usual, to attempt 
 something more full and satisfactory than has yet been 
 proposed to tjie public. 
 Ij All reasonings concerning matter of fact seem to 
 ibe founded on the relation of Cause and Effect. By 
 means of that relation alone we can go beyond the 
 evidence of our memory and senses. If you were to 
 ask a man, why he believes any matter of fact, which 
 is absent; for instance, that his friend is in 'the coun- 
 try, or in France ; he would give you a reason ; and 
 this reason would be some other fact ; as a letter re- 
 ceived frpm him, or the knowledge of his former f^? 
 
HUMAN UNDERSTANDING, 25 
 
 olutions and promises. A man finding a watch or any 
 other machine in a desert island, would conclude that 
 there had once been men in that island. JAJI our rea- 
 sonings concerning fact are of the same nature^ And 
 here it is constantly supposed that there is a connexion 
 between the present fact and that which is inferred 
 from it. Were there nothing to bind them together, 
 the inference would be entirely precarious. The hear- 
 ing of an articulate voice and rational discourse in the 
 dark assures us of the presence of some person : 
 Why ? because these are the effects of the huinan make 
 and fabric, and closely connected with it. /if we anat- 
 omize all the other reasonings of this nature, we shall 
 find that they are founded on the relation of cause and 
 effect, and that this relation is either near or remote, 
 direct or collateral. Heat and light are collateral 
 effects of fire, and the one effect may justly be inferred 
 from the other.^ 
 
 If we would satisfy ourselves, therefore, concern- 
 ing the nature of that evidence, which assures us of , 
 matters of fact,{^e must enq uirei how jwe arrive at the jk 
 kno3vledge of cause and effectTj^ I ^ ^ 
 
 :,J-shall venture t^ affirm, as a general proposition, 
 which admits of no exception, that the knowledge of > 
 
 this relation is not in any instance, attained by rea-^/ 
 sonings a ^ort ^vX arises lentirely from experience, J^ 
 when we find'that any particular objects are constantly \ 
 conjoined with each other. Let an object be presented 
 to a man of ever so strong natural reason and abilities ; 
 if that object be entirely new to him, he will not be 
 able, by the most accurate examination of its sensible 
 qualities, to discover any of its causes or effects. 
 Adam, though his rational faculties be supposed, at 
 the very first, entirely perfect, could not have inferred 
 
96 AN ENQUIRY CONCERNING 
 
 from the fluidity and transparency of water that it 
 would suffocate him, or from the light and warmth of 
 fire that it would consume him. No object ever dis- 
 covers, by the qualities which appear to the senses, 
 either the causes which produced it, or the effects 
 which will arise from it ; Tnor can our reason, un- 
 assisted by experience, ever draw any inference con 
 ^\ cerjjing real existence and matter of fac^tA^ 
 
 r This proposition, that causes and effects are discover- 
 ablCy not by reason but by experience'^WX readily be ad- 
 mitted with regard to such obj^s, as we remember 
 to have once been altogether unknown to us; since 
 we must be conscious of the utter inability, which we 
 then lay under, of foretelling what would arise from 
 them. Present two smooth pieces of marble to a man 
 who has no tincture of natural philosophy ; he will 
 never discover that they will adhere together in such 
 a manner as to require great force to separate them in 
 a direct line, while they make so small a resistance to 
 a lateral pressure. Such events, as bear little analogy 
 to the common course of nature, are also readily con- 
 fessed to be known only by experience ; nor does any 
 man imagine that the explosion of gunpowder, or the 
 attraction of a loadstone, could ever be discovered by 
 arguments a priori. In like manner, when an effect 
 is supposed to depend upon an intricate machinery or 
 secret structure of parts, we make no difficulty in at- 
 tributing all our knowledge of it to experience. Who 
 ") will assert that he can give the ultimate reason, why 
 / milk or bread is proper nourishment for a man, not 
 for a lion or a tiger? 
 
 But the same truth may not appear, at first sight, 
 to have the same evidence with regard to events, 
 which have become familiar to us from our first ap 
 
HUMAN UNDERSTANDING. 27 
 
 pearance in the world, which bear a close analogy to 
 the whole course of nature, and which are supposed 
 to depend on the simple qualities of objects, without 
 any secret structure of parts. We are apt to imagine 
 that we could discover these effects by the mere opera- 
 tion of our reason, without experience. We fancy, that 
 were we brought on a sudden into this world, we could 
 at first have inferred that one Billiard-ball would com- 
 municate motion to another upon impulse ; and that 
 we needed not to have waited for the event, in order 
 to pronounce with certainty concerning it. Such is 
 the influence of custom, that, where it is strongest, it 
 not only covers our natural ignorance, but even con- 
 ceals itself, and seems not to take place, merely be- 
 cgjjt^e it is found in the highest degree. 
 JUBut to convince us that all the laws of nature, and /^ 
 all the operations of bodies without exception, are * 
 known only by experi^ence, the following reflections-^ 
 may, perhaps, sufficej Were any object presented to 
 us, and were we required to pronounce concerning the 
 effect, which will result from it, without consulting 
 past observation ; after what manner, I beseech you, 
 must the mind proceed in this operation? It must in- 
 vent or imagine some event, which it ascribes to the 
 object as its effect ; and it i^ plain that this invention 
 must be entirely arbitrary. l,,The mind can never pos- 
 sibly find the effect in the supposed cause, by the most 
 accurate scrutiny and examination. For the effect is 
 totally different from the cause, and consequently can 
 never be discovered in ixT] Motion in the second Bil- 
 liard-ball is a quite distmct event from motion in the 
 first ; nor is there anything in the one to suggest the 
 smallest hint of the other. A stone or piece of metal 
 raised into the air, and left without any support, im- 
 
28 AN ENQUIRY CONCERNING 
 
 mediately falls : but to consider the matter a priori^ is 
 there anything we discover in this situation which can 
 beget the idea of a downward, rather than an upward, 
 or any other motion, in the stone or metal? ^ 
 
 And as the first imagination or invention of a par- 
 ticular effect, in all natural operations, is arbitrary, 
 where we consult not experience ; so must we also es- 
 teem the supposed tie or connexion between the cause 
 and effect, which binds theri together, and renders it 
 impossible that any other effect could result from the 
 operation of that cause. When I see, for instance, 
 a Billiard-ball moving in a straight line towards an- 
 other ; even suppose motion in the second ball should 
 by accident be suggested to me, as the result of their 
 contact or impulse ; may I not conceive, that a hun- 
 dred different events might as well follow from that 
 cause ? May not both these balls remain at absolute 
 rest ? May not the first ball return in a straight line, 
 or leap off from the second in any line or direction ? 
 All these suppositions are consistent and conceivable. 
 Why then should we give the preference to one, which 
 is no more consistent or conceivable than the rest ? 
 All our reasonings a priori vi\\\ never be able to show 
 us any foundation for this preference. 
 
 In a word, then,y^ery effect is a distinct event 
 from its cause'./ It could not, therefore, be discovered 
 in the cause, and the first invention or conception of 
 ^it, a priori^ must be entirely arbitrary. And even after 
 it is suggested, the conjunction of it with the cause 
 must appear equally arbitrary ; since there are always 
 many other effects, which, to reason, must seem fully 
 as consistent and natural. In vain, therefore, should 
 we pretend to determine any single event, or infer any 
 
HUMAN UNDERSTANDING, 29 
 
 cause or effect, without the assistance of observation 
 and experience. 
 
 Hence we may discover the reason why no philos- 
 opher, who is rational and modest, has ever pretended 
 to assign the ultimate cause of any natural operation, 
 or to show distinctly the action of that poweif, which 
 produces any single effect in the universe. ^ It is con- 
 fessed, that the utmost effort of human reason is to re- <» 
 duc.e the principles, productive of natural phenomena, 
 to a greater simplicity, and to resolve the many par- 
 ticular effects into a few general causes, by means of 
 reasonings from analogy, experience, and observation^ 
 But as to the causes^ of these general causes, we should y 
 in vain attempt their discovery ;' nor shall we ever be 
 able to satisfy ourselves, by any particular explication 
 of them. These ultimate springs and principles are 
 totally shut up from human curiosity and enquiry. 
 Elasticity, gravity, cohesion of parts, communication 
 of motion by impulse; these are probably the ultimate 
 causes and principles which we ever discover in nature; 
 and we may esteem ourselves sufficiently happy, if, by 
 accurate inquiry and reasoning, we can trace up the 
 particular phenomena to, or near to, these general 
 principles.! The most perfect philosophy of the natural 
 kind only staves off our ignorance a little longer: as 
 perhaps the most perfect philosophy of the moral or 
 metaphysical kind serves only to discover larger por- 
 tions of it. Thus the observation of human blindness , 
 and weakness is the result of all philosophy, and meets I 
 us at every turn, in spite of our endeavours to elude i 
 or avoid it. 
 
 Nor is geometry, when taken into the assistance of 
 natural philosoph}^, ever able to remedy this defect, or 
 lead us into the knowledge of ultimate causes, by all 
 
30 AN ENQ UIR Y CONCERNING 
 
 that accuracy of reasoning for which it is so justly cel- 
 ebrated. Every part of mixed mathematics proceeds 
 upon the supposition that certain laws are established 
 by nature in her operations ; and abstract reasonings 
 are employed, either to assist experience in the discov- 
 ery of these laws, or to determine their influence in 
 particular instances, where it depends upon any pre- 
 cise degree of distance and quantity. Thus, it is a law 
 of motion, discovered by experience, that the moment 
 or force of any body in motion is in the compound ra- 
 tio or proportion of its solid contents and its velocity ; 
 and consequently, that a small force may remove the 
 greatest obstacle or raise the greatest weight, if, by 
 any contrivance or machinery, we can increase the ve- 
 locity of that force, so as to make it an overmatch for 
 its antagonist. Geometry assists us in the application 
 of this law, by giving us the just dimensions of all the 
 parts and figures which can enter into any species of 
 machine ; but still the discovery of the law itself is ow- 
 ing merely to experience, and all the abstract reason- 
 ings in the world could never lead us one step towards 
 the knowledge of it. When we reason a priori^ and 
 consider merely any object or cause, as it appears to 
 the mind, independent of all observation, it never could 
 suggest to us the notion of any distinct object, such as 
 its effect ; much less, show us the inseparable and in- 
 violable connexion between them. A man must be 
 very sagacious who could discover by reasoning that 
 crystal is the effect of he^t, and ice of cold, without 
 being previously acquainted with the operation of these 
 qualities. 
 
 Part II. 
 
 But we have not yet attained any tolerable satisfac- 
 tion with regard to the question first proposed. Each 
 
HUMAN UNDERSTANDING. 31 
 
 solution still gives rise to a new question as difficult 
 as the foregoing, and leads us on to farther enquiries. 
 When it is asked, What is the nature of all our reason- j y 
 ings concerning matter of fact ? the proper answer seems' ^^ 
 to be, that they are founded on the relation of cause 
 and effect. When again it is asked. What is the foun- 
 dation of all our reasonings a7id conclusions ^concerning that 
 relation ? it may be replied in one word, Experience. 
 But if we still carry on our sifting humour, and ask, 
 What is the foundation of all conclusions from experience? \ 
 this implies a new question, which may be of more 
 difficult solution and explication. Philosophers, that 
 give themselves airs of superior wisdom and sufficiency, 
 have a hard task when they encounter persons of in- 
 quisitive dispositions, who push them from every cor- 
 ner to which they retreat, and who are sure at last to 
 bring them to some dangerous dilemma. The best ex- 
 pedient to prevent this confusion, is to be modest in I 
 our pretensions ; and^ven to discover the difficulty \ 
 ourselves before it is objected to us. By this means, \ 
 we may make a kind of merit of our very ignorance. 
 I shall content myself, in this section, with an easy 
 task, and shall pretend only to give a negative answer 
 to the question here proposed. I say then, that, even ^ 
 after we have experience of the operations of cause ■. 
 and effect, our conclusions from that experience are n, 
 not founded on reasoning, or any process of the under- U\ 
 standing. This answer we must endeavour both to ex- 
 plajii^and to defend. 
 
 j^Lt must certainly be allowed, that nature has kept 
 us at a great distance from all her secrets, and has af- 
 forded us only the knowledge of a few superficial qual- 
 ities of objects ; while she conceals from us those pow- 
 ers and principles on which the influence of those ob- 
 
 \ 
 
32 AN ENQUIRY CONCERNING 
 
 jects entirely depends^ Our senses inform us of the 
 colour, weight, and consistence of bread ; but neither 
 sense nor reason can ever inform us of those qualities 
 which fit it for the nourishment and support of a human 
 body. Sight or feeling conveys an idea of the actual 
 motion of bodies ; but as to that wonderful force or 
 power, which would carry on a moving body for ever 
 in a continued change of place, and which bodies never 
 lose but by communicating it to others ; of this we can- 
 r not form the most distant conception. But notvv^ith- 
 
 standing this ignorance of natural powers^ and prin- 
 ciples,! we always presume, when we see like sensible 
 qualities, that they have like secret powers, and expect 
 that effects, similar to those which we have experienced, 
 will follow from them 3 If a body of like colour and 
 consistence with that bread, which we have formerly 
 eat, be presented to us, we makS no' scruple of repeat- 
 ing the experiment, and foresee, with certainty, like 
 nourishment and support, f N^ this is a process of 
 the mind or thought, of which I would willingly know 
 the foundation.^ It is allowed on all hands that there 
 is no known connexion between the sensible qualities 
 and the secret powers; and consequently, that the mind 
 is not led to form such a conclusion concerning their 
 constant and regular conjunction, by anything which it 
 _ knows of their nature. ' As to past Experience, it can be 
 allowed to give direct and certain information^ Jhpse 
 precise objectsonly, And^that precise period of time, 
 which fell under its cognizance : but why this experi- 
 ence should be extended to future times, and to other 
 objects, which, for aught vt^e know, may be only in ap- 
 
 1 The word. Power, is here used in a loose and popular sense. The more 
 accurate explication of it would give additional evidence to this argument 
 See Sect. 7. 
 
HUMAN UNDERSTANDING. 33 
 
 pearance similar ; this is the main question on which \ 
 I would insist^ The bread, which I formerly eat, nour- 
 ished me ; that is, a body of such sensible qualities 
 was, at that time, endued with such secret powers : 
 but does it follow, that other bread must also nourish 
 me at another time, and that like sensible qualities 
 must always be attended with like secret powers? The 
 consequence seems nowise necessary. At least, it must 
 be acknowledged that there is here a consequence 
 drawn by the mind ; that there is a certain step taken; 
 a process of thought, and an inference, which wants# 
 to be explained. \These two propositions are fa 
 being the same, I have found that siMi an objecti 
 ways been attended with such an effect, and I fores 
 other objects, which are, in appearance, similar, mi 
 attended with sirni/ar^fiSSS^j^Sill allow, if you please, ' 
 that the one propoMion majKListly be inferred from 
 the other; I know, wi ' tl^t it always is inferred. 
 But if you insist that thf iiiierence is made by a chain] 
 of reasoning, I desire you to produce that reasoning. ; 
 The connexion between these propositions is not intu- 
 itive. Tifiere is required a medium, which may enable 
 the mind to draw such an inference, if indeed it be 
 drawn by reasoning and argumerit^jj^at that me- 
 dium is, I must confess, passes nj^^B^^Nihension ; 
 and it is incumbent on those to ]> r:<a^-ii ce-^t, who as- 
 sert that it really exists, and is the origin of all our 
 conclusions concerning;; .j^^H^BTfact. 
 
 This negativdfeirgiunent mus t co.i talnly, in process 
 of time, become altoge^m^onvj^Rig, if many pene- 
 trating and able phllosop^^B^prturn their enquiries 
 this way and no one be ever able to discover any con- 
 necting proposition or intermediate step, which sup- 
 le understanding in this conclusion. But as the 
 
 po^^l^e 
 
^ 
 
 \ 
 
 34 AN ENQUIRY CONCERNING 
 
 question is yet new, every reader may not trust so far 
 to his own penetration, as to conclude, because an ar- 
 gument escapes his enquiry, that therefore it does not 
 really exist. For this reason it may be requisite to 
 venture upon a more difficult task ; and enumerating 
 all the branches of human knowledge, endeavour to 
 •s,show that none of them can afford such an argument. 
 ] AH rea sonings m_av be dUvj^ed_jnt^Jws. Mnds, 
 namely, d emon s trative reas oning, or that concerning 
 relations of idear., and moral r easoning, or that con- 
 erning matter of fact and existence, r That there are 
 onstrative arguments in the case seems evident ; 
 implies r^contradiction that the course of na- 
 y change, and that an object, seemingly like 
 which we have experienced, may be attended 
 with different or contra|^B|^^ May I not clearly 
 and distinctly conceiv^^^^^^Biy, falling from the 
 clouds, and which, in^^^^^Hlespects, resembles 
 snow, has yet the taste ^M^Wr feeling of fire ? Is 
 there any more intelligible proposition than to affirm, 
 that all the trees will flourish in December and Tanu- 
 ary, and decay in May and June ? j Now whatever is 
 intelligible, and can be distinctly conceived, implies 
 and can never be proved false by any 
 ent or abstract reasoning a priori. 
 re, engaged by arguments to put 
 trust in past experience, and make it the stamdard of 
 our future judgemen|j^H^|guments must be proba- 
 ble only, or such aA^ga^^^M:er ofgfact and real exi 
 istence, accordin^B^ thf^^^Kon above mentioned. 
 But that there is no ar^uii^^^^this kind, must appeat," 
 if our explication of that species of reasoning be ad- 
 mitted as solid and satisfactory^) We have said that 
 all arguments concerning existence are founded 
 
 inteiiigiDie, ana can 
 j no contradicti^^and ( 
 j demonstry|^^^^^( 
 jlf we im^^Bor( 
 
 :d^g|K 
 
HUM AM UNDERSTANDING, 35 
 
 relation of cause and effect ; that our knowledge of that 
 relation is derived entirely from experience -T^and that 
 all our experimental conclusions procee3"'^upon the 
 supposition that the future will be conformable to the 
 past. To endeavour, therefore, the proof of this last 
 supposition by probable arguments, or arguments re- 1 
 garding existence, must be evidently going in a circle, 
 and taking that for granted, which is the very point in 
 question. 
 
 In reality, all arguments from experience are found- 
 ed on the similarity which we discover among natural 
 objects, and by which we are induced to expect effects 
 similar to those which we have found to f ollow ft6wa4-Vv • 
 such objects. And though none but a fool or madman 
 will ever pretend to dispute the authority of experi- 
 ence, or to reject that great guide of human life, it 
 may surely be allowed,,^^>^losopher to have so much 
 curiosity at least as to examine theJ£nnciple of human 11 
 nature, which gives this mighty authority to experience^jM 
 and makes us draw advantage from that similarity 
 vidiich nature has placed among different objects. 
 /From causes which appear si?nihir we expect similar \ 
 effects. 7 This is the sum of all our experimental con- I 
 clusidns^/Now it seems evident that, if this conclusion 
 were formed by reason, it would be aa. perfect at first, 
 and upon one instance, as after ever so long a course 
 of experience. But the case is far otherwise. Nothing 
 so like as eggs; yet no one, on account of this appear- 
 ing similarity, expects the'"^feS;rtL'^t,aste and relish in all 
 of them. It is only af ten^* IprigiljCburse of uniform ex- 
 periments in any kind, that we attain a firm reliance 
 and 'security with regard to a particular £vent. Now 
 where is that process of reasoning ^mch, from one 
 instance, draws a conclusion, so different from that 
 
36 AN ENQUIRY CONCERNING 
 
 which it infers from a hundred instances that are no- 
 wise different from that single one ? This question I 
 propose as much for the sake of information, as with 
 an intention of raising difficulties. I cannot find, I 
 cannot imagine any su.ch reasoning. But I keep my 
 mind still open to instruction, if any one will vouch- 
 safe to bestow it on me. 
 
 Should it be said that, from a number of uniform 
 experiments, we infer a connexion between the sensi- 
 ble qualities and the secret powers ; this, I must con- 
 fess, seems the same difficulty, couched in different 
 terms. The question still recurs, on what process of 
 argument this inference is founded ? Where is the me- 
 dium, the interposing ideas, which join propositions 
 so very wide of each other ? It is confessed that the 
 colour, consistence, and other sensible qualities of 
 bread appear not, of themselves, to have any connex- 
 ion with the secret powers of nourishment and support. 
 For otherwise we could infer these secret powers from 
 the first appearance of these sensible qualities, without 
 the aid of experience ; contrary to the sentiment of all 
 philosophers, and contrary to plain matter of fact. 
 Here, then, is our natural state of ignorance with re- 
 gard to the powers and influence of all objects. How 
 is this remedied^iJ^ experience ? It only shows us a 
 number of uniform effects, resulting from certain ob- 
 jjects, and teaches us that those particular objects, at 
 that particular time, were endowed with such powers 
 and forces. When a new object, endowed with simi- 
 lar sensible qualities, is produced, we expect similar 
 powers and forces, and look for a like effect. From a 
 body of like colour and consistence with bread we ex- 
 pect like nourishment and support. But this surely 
 is a step or progress of the mind, which wants to be 
 
HUMAN UNDERSTANDING. 37 
 
 explained. When a man says, I have found , in all past j 
 instances f such sensible qualities conjoined with such secret i 
 powers : And when he says, Similar sensible qualities j 
 will always be conjoined with similar secret powers ^ he is 
 not guilty of a tautology, nor are these propositions in 
 any respect the same. You say that the one proposi- 
 tion is an inference from the other. But you must con- 
 fess that the inference is not intuitive ; neither is it 
 demonstrative : Of what nature is it, then ? To say it 
 is experimental, is begging the question. For all in- 
 ferences from experience suppose, as their foundation, 
 that the future will resemble the past, and that similar 
 powers will be conjoined with similar sensible quali- 
 ties. If there be any suspicion that the course of na- 
 ture may change, and that the past may be no rule for 
 the future, all experience becomes useless, and can 
 give rise to no inference or conclusion. It is impossi- 
 ble, therefore, that any arguments from experience can 
 prove this resemblance of the past to the future; since 
 all these arguments are founded on the supposition of 
 that resemblance. Let the course of things be allowed 
 hitherto ever so regular ; that alone, without some new 
 argument or inference, proves not that, for the future, 
 it will continue so. In vain do you pretend to have 
 learned the nature of bodies from your past experience. 
 Their secret nature, and consequently all their effects 
 and influence, may change, without any change in their 
 sensible qualities. This happens sometimes, and with 
 regard to some objects : Why may it happen always, ^__ 
 and with regard to all objects ? What logic, what 
 process of argument secures you against this supposi- 
 tion ? jMy practice. VOU ^ ay, j-(^fntp<; my dnnhts. Rnt ^ 
 you mistake Jiie- ourport jai my questia n^ ^s an agen t, \ 
 I am quite satisfied in the point : ^"^ n^ R phf'^?°^r^'=^^> | 
 
38 AKT ENQUIRY CONCERNING 
 
 Jwho has some share of curiosity, I will not say scep- 
 /ticism, I want to learn the foundation of this inference. 
 No reading, no enquiry has yet been able to remove 
 my difficulty, or give me satisfaction in a matter of 
 such importance. Can I do better than propose the 
 difficulty to the public, even though, perhaps, I have 
 small hopes of obtaining a solution ? We shall, at 
 least, by this means, be sensible of our ignorance, if 
 we do not augment our knowledge. 
 f^ I must confess that a man is guilty of unpardonable 
 I arrogance who concludes, because an argument has 
 \escaped his own investigation, that therefore it does 
 [not really exist. 1 must also confess that, though all 
 the learned, for several ages, should have employed 
 themselves in fruitless search upon any subject, it may 
 still, perhaps, be rash to conclude positively that the 
 subject must, therefore, pass all human comprehension. 
 Even though we examine all the sources of our knowl- 
 edge, and conclude them unfit for such a subject, there 
 may still remain a suspicion, that the enumeration is 
 not complete, or the examination not accurate. But 
 with regard to the present subject, there are some con- 
 siderations which seem to remove all this accusation 
 of arrogance or suspicion of mistake. 
 
 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 ob- 
 jects, by observing the effects which result from them. 
 When a child has felt the sensation of pain from touch- 
 ing the flame of a candle, he will be careful not to put 
 his hand near any candle ; but will expect a similar 
 effect from a cause which is similar in its sensible qual- 
 ities and appearance. If you assert, therefore, that 
 the understanding of the child is led into this conclu- 
 
HUMAN UNDERSTANDING 39 
 
 sion by any process of argument or ratiocination, I may 
 justly require you to produce that argument ; nor have 
 you any pretense to refuse so equitable a demand. You 
 cannot say that the argument is abtruse, and may pos- 
 sibly escape your enquiry ; since you confess that it is 
 obvious to the capacity of a mere infant. If you hesi- 
 tate, therefore, a moment, or if, after reflection, you pro- 
 duce any intricate or profound argument, you, in a man- 
 ner, give up the question, and confess that it is not 
 reasoning which engages us to suppose the past re- 
 sembling the future, and to expect similar effects from 
 causes which are, to appearance, similar. This is the 
 proposition which I intended to enforce in the present 
 section. If I be right, I pretend not to have made any 
 mighty discovery. And if I be wrong, I must acknowl- 
 edge myself to be indeed a very backward scholar ; 
 since I cannot now discover an argument which, it 
 seems, was perfectly familiar to me long before I was 
 out of my cradle. 
 
SECTION V. 
 
 SCEPTICAL SOLuf ION OF THESE DOUBTS. 
 
 Part I. 
 
 THE passion for philosophy, like that for religion, 
 seems liable to this inconvenience, that, though it 
 aims at the correction of our manners, and extirpation 
 of our vices, it may only serve, by imprudent manage- 
 ment, to foster a predominant inclination, and push 
 the mind, with more determined resolution, towards 
 that side which already draws too much, by the bias 
 and propensity of the natural temper. It is certain 
 that, while we aspire to the magnanimous firmness of 
 the philosophic sage, and endeavour to confine our 
 pleasures altogether- within our own minds, we may, 
 at last, render our philosophy like that of Epictetus, 
 and other Stoics, only a more refined system of selfish- 
 ness, and reason ourselves out of all virtue as well as 
 social enjoyment. While we study with attention the 
 vanity of human life, and turn all our thoughts towards 
 the empty and transitory nature of riches and honours, 
 we are, perhaps, all the while flattering our natural 
 indolence, which, hating the bustle of the world, and 
 drudgery of business, seeks a pretence of reason to 
 give itself a full and uncontrolled indulgence. There , 
 is, however, one species of philosophy which seems 
 little liable to this inconvenience, and that because it 
 •strikes in with no disorderly passion of the human 
 
HUMAN UNDERSTANDING. 
 
 41 
 
 mind, nor can mingle itself with any natural affection 
 or propensity; and that is the Academic or Sceptical 
 philosophy. The academics always talk of doubt and 
 suspense of judgement, of danger in hasty determina- 
 tions, of confining to very narrow bounds the enquiries 
 of the understanding, and of renouncing all specula- 
 tions which lie not within the limits of common life 
 and practice. SNothing, therefore, can be more con- 
 trary than such a philosophy to the supine indolence 
 of the mind, its rash arrogance, its lofty pretensions, 
 and its superstitious credulity .^Every passion is mor- 
 tified by it, except the love of ifruth ; and that passion 
 never is, nor can be, carried to too high a degree. It 
 is surprising, therefore, that this philosophy, which, 
 in almost every instance, must be harmless and inno- 
 cent, should be the subject of so much groundless re- 
 proach and obloquy. But, perhaps, the very circum- 
 stance which renders it so innocent is what chiefly 
 exposes it to the public hatred and resentment. By 
 flattering no irregular passion, it gains few partizans: 
 By opposing so many vices and follies, it raises to 
 itself abundance of enemies, who stigmatize it as 
 libertine, profane, and irreligious. 
 
 Nor need we fear that this philosophy, while it en- 
 deavours to limit our enquiries to common life, should 
 ever undermine the reasonings of common life, and 
 carry its doubts so far as to destroy all action, as well 
 as speculation, feature will always maintain her rights, 
 and prevail in the end over any abstract reasoning 
 whatsoeverT^Though we should conclude, for instanceT^ 
 as in the foregoing section, that, in all reasonings from 
 experience, there is a step taken by the mind which is 
 not supported by any argument or process of the un- 
 derstanding ; there is no danger that these reasonings, 
 
42 AN ENQUIRY CONCERNING 
 
 on which almost all knowledge depends, will ever be 
 affected by such a discovery. If the mind be not en- 
 gaged by argument to make this step, it must be in- 
 /duced by some other principle of equal weight and 
 j / authority ; and that principle will preserve its influence 
 \ j as long as human nature remains the same. What 
 / I that principle is may well be worth the pains of enquiry. 
 Suppose a person, though endowed with the strong- 
 
 est faculties of reason and reflection, to be brought on 
 a sudden into this world ; he would, indeed, immedi- 
 ately observe a continual succession of objects, and 
 one event following another ; but he would not be able 
 to discover anything farther. He would not, at first, 
 by any reasoning, be able to reach the idea of cause 
 and effect ; since the particular powers, by which all 
 natural operations are performed, never appear to the 
 senses; nor is it reasonable to conclude, merely be- 
 cause one event, in one instance, precedes another, 
 that therefore the one is the cause, the other the effect. 
 Their conjunction may be arbitrary and casual. There 
 may be no reason to infer the existence of one from 
 the appearance of the other. And in a word, such a 
 person, without more experience, could never employ 
 his conjecture or reasoning concerning any matter of 
 fact, or be assured of anything beyond what was im- 
 mediately present to his memory and senses. 
 
 Suppose, again, that he has acquired more experi- 
 ence, and has lived so long in the world as to have ob- 
 served familiar objects or events to be constantly con- 
 joined together; what is the consequence of this ex- 
 perience ? He immediately infers the existence of one 
 object from the appearance of the other. Yet he has 
 not, by all his experience, acquired any idea or knowl- 
 edge of the secret power by which the one object pro- 
 
l\ 
 
 HUMAN UNDERSTANDING. 43 
 
 duces the other ; nor is it, by any process of reasoning, 
 he is engaged to draw this inference. But still he finds 
 himself determined to draw it : And though he should 
 be convinced that his understanding has no part in 
 the operation, he would nevertheless continue in the 
 same course of thinking. There is some other princi- 
 ple which determines him to form such a conclusion. 
 
 This principle is Custom or Hab it. For wherever | 
 the repetition of any particular act or operation pro-i{ 
 duces a propensity to renew the same act or operation, \; 
 without being impelled by any reasoning or process of 
 the understanding, we always say, that this propensity 
 is the effect of Custo?ft. By employing that word, we- 
 pretend not to have given the ultimate reason of such 
 a propensity. We only point out^a^rinciple of human 
 nature, which is universally acknowledged, and which 
 is well known by its effects/ Perhaps we can push our 
 enquiries no farther, or pretend to give the cause of /^•^'^.. 
 this cause ; but must rest contented with it as the ul- 7 ^-a^ 
 timate principle, which we can assign, of all our con- ^ ^^ 
 elusions from experience. It is sufficient satisfaction, ^''^ 
 that we can go so far, without repining at the narrow- ^^< 
 ness of our faculties because they will carry us no far. 
 Xhef. And it is certain we here advance a very intel- 
 ligible proposition at least, if not a true one, when we 
 assert that, after the constant conjunction of two ob- 
 jects — heat and flame, for instance, weight and solidity 
 — we are determmed by_custom alone to expect the 
 oiie^hs^cath^^ This hypothesis 
 
 seems even the only one which explains the difficulty," 
 why we draw, from a thousand instances, an inference 
 which we are not able to draw from one instance, thixi 
 is, in no respect, different from them. Reason is incap- 
 able of any such variation. The conclusions which it 
 
 .V-- 
 
44 AN ENQUIRY CONCERNING 
 
 draws from considering one circle are the same which 
 
 it would form upon surveying all the circles in the 
 
 universe. But no man, having seen only one body 
 
 move after being impelled by another, could infer that 
 
 , every other body will move after a like impulse. '■- Alt 
 
 i inferences from experience, therefore, are effects of 
 
 li custom, not of reasoning. M y^ 
 
 '< 1 Nothing is more useful than for writers, even, on morale political, or 
 
 physical subjects, to distinguish between reason and experience, and to sup- 
 pose, that these species of argumentation are entirely diiferent from each 
 other. The former are taken for the mere result of our intellectual faculties, 
 which, by considering A /r/^i^/ the nature of things, and examining the effects, 
 that must follow from their operation, establish particular principles of sci- 
 ence ai:d philosophy. The latter are supposed to be derived entirely froai 
 sense and observation, by which we learn what has actually resulted from the 
 operation of particular objects, and are thence able to infer, what will, f i)r 
 thefuture, result from them. Thus, for instance, the limitations and restraints 
 of civil government, and a legal constitution, may be defended, either from 
 reason, which reflecting on the great frailty and corruption of human nature, 
 teaches, that no man can safely be trusted with unlimited authority; or from 
 experience a.nd history, which inform us of the enormous abuses, that ambi- 
 
 / tion, in every age and country, has been found to make of so imprudent a 
 
 / confidence. 
 
 ' The same distinction between reason and experience is maintained in all 
 
 our deliberations concerning the conduct of life ; while the experienced 
 statesman, general, physician, or merchant is trusted and followed ; and the 
 unpractised novice, with whatever natural talents endowed, neglected and 
 despised. Though it be allowed, that reason may form very plausible 
 conjectures with regard to the consequences of such a particular conduct in 
 such particular circumstances ; it is still supposed imperfect, without the 
 assistance of experience, which is alone able to give stability and certainty 
 to the maxims, derived from study and reflection. 
 
 But notwithstanding that this distinction be thus universally received, 
 both in the active speculative scenes of life, I shall not scruple to pronounce, 
 that it is, at bottom, erroneous, at least, superficial 
 
 If we examine those arguments, which, in any of the sciences above men- 
 tioned, are supposed to be the mere effects of reasoning and reflection, they 
 will be found to terminate, at last, in some general principle or conclusion, 
 for which we can assign no reason but observation and experience. The only 
 difference between them and those maxims, which are vulgarly esteemed the 
 result of pure experience, is, that the former cannot be established without 
 some process of thought, and some reflection on what we have observed, in 
 order to distinguish its circumstances, and trace its consequences : Whereas 
 in the latter, the experienced event is exactly and fully familiar to that which 
 we infer as the result of any particular situation. The history of a Tiberius 
 or a Nero makes us dread a like tyranny, were our monarchs freed from the 
 restraints of laws and senates .• But the observation of any fraud or cruelty 
 
HUMAN- UNDERSTANDING, 45 
 
 J^ustomj^then^Js the great guide of human life. It 
 is that principle alone which renders our experience 
 useful to us, and makes us expect, for the future, a 
 similar train of events with those which have appeared 
 in the past. Without the influence of custom, we 
 should be entirely ignorant of every matter of fact be- 
 yond what is immediately present to the memory and 
 senses. We should never know how to adjust means 
 to ends, or to employ our natural powers in the pro- 
 duction of any effect. There would be an end at once 
 of all action, as well as of the chief part of speculation. 
 
 But here it may be proper to remark, that though 
 our conclusions from experience carry us beyond our 
 memory and senses, and assure us of matters of fact 
 which happened in the most distant places and most 
 remote ages, yet some fact must always be present to 
 the senses or memory, from which we may first pro- 
 ceed in drawing these conclusions. A man, who should 
 find in a desert country the remains of pompous build- 
 ings, would conclude that the country had, in ancient 
 
 in private life is sufficient, with tlie aid of a little thought, to give us the same 
 apprehension; while it serves as an instance of the general corruption of 
 human nature, and shows us the danger which we must incur by reposing an 
 entire confidence in mankind. In both cases, it is experience which is ulti- 
 mately the foundation of our inference and conclusion. 
 
 There is no man so young and unexperienced, as not to have formed, from 
 observation, many general and just maxims concerning human affairs and the 
 conduct of life ; but it must be confessed, that, when a man comes to put 
 these in practice, he will be extremely liable to error, till time and farther 
 experience both enlarge these maxims, and teach him their proper use and 
 application. In every situation or incident, there are many particular and 
 seemingly minute circumstances, which the man of greatest talent is, at first, 
 apt to overlook, though on them the justness of his conclusions, and conse- 
 quently the prudence of his conduct, entirely depend. Not to mention, that, 
 to a young beginner, the general observations and maxims occur not always 
 on the proper occasions, nor can be immediately applied with due calmness 
 and distinction. The truth is, an unexperienced reasoner could be no reat 
 soner at all, were he absolutely unexperienced; and when we assign tha 
 character to any one, we mean it only in a comparative sense, and suppose 
 him possessed of experience, in a smaller and more imperfect degree. 
 
46 AN" ENQ UIR Y CONCERNING 
 
 times, been cultivated by civilized inhabitants; but 
 did nothing of this nature occur to him, he could never 
 form such an inference. We learn the events of former 
 ages from history ; but then w^e must peruse the vol- 
 umes in which this instruction is contained, and thence 
 carry up our inferences from one testimony to another, 
 till we arrive at the eyewitnesses and spectators of 
 these distant events. In a word, if we proceed not 
 upon some fact, present to the memory or senses, our 
 reasonings would be merely hypothetical ; and how- 
 ever the particular links might be connected with each 
 other, the whole chain of inferences would have noth- 
 ing to support it, nor could we ever, by its means, ar- 
 rive at the knowledge of any real existence. If I ask 
 why you believe any particular matter of fact, which 
 you relate, you must tell me some reason ; and this 
 reason will be some other fact, connected with it. 
 But as you cannot proceed after this manner, in infini- 
 tum, you must at last terminate in some fact, which is 
 present to your memory or senses ; or must allow that 
 your belief is entirely without foundation. 
 
 What, then, is the conclusion of the whole matter ? 
 A simple one ; though, it must be confessed, pretty 
 remote from the common theories of philosophy, f All 
 belief of matter of fact or real existence is derived 
 merely from some object, present to the memory or 
 senses, and a customary conjunction between that and 
 some other object J Or in other words; having found 
 in many instances, that any two kinds of objects — 
 flame and heat, snow and cold — have always been con- 
 joined together ; if flame or snow be presented anew 
 to the senses, the mind is carried by custom to expect 
 heat or cold, and to believe that such a quality does 
 exist, and will discover itself upon a nearer approach. 
 
HUMAN UNDERSTANDING. 47 
 
 This belief is the necessary result of placing the mind 
 in such circumstances. It is an operation of the soul, 
 when we are so situated, as unavoidable as to feel the 
 passion of love, when we receive benefits ; or hatred,> 
 when we meet with injuries. All these operations areVTl ' *2C* 
 a species of natural instincts, which no reasoning or Jy **^ !£ -^ 
 process of the thoughtand understanding is able either 
 to produce or to prevent. "" 
 
 At this point, it would be very allowable for us to 
 stop our philosophical researches. In most questions 
 we can never make a single step farther; and in all 
 questions we must terminate here at last, after our most 
 restless and curious enquiries. But still our curiosity 
 will be pardonable, perhaps commendable, if it carry 
 us on to still farther researches, and make us examine 
 more accurately the nature of this belief, and of the 
 customary conjunction, whence it is derived. / By this 
 means we may meet with some explications and anal- 
 ogies that will give satisfaction ; at lea. t to such as 
 love the abstract sciences, and can be entertained with 
 speculations, which, however accurate, may still retain 
 a degree of doubt and uncertainty. As to readers of 
 a different taste ; the remaining part of this section is 
 not calculated for them, and the following enquiries 
 may well be understood, though it be neglected. 
 
 Part II. 
 
 Nothing is more free than the imagination of man ; 
 and though it cannot exceed that original stock of 
 ideas furnished by the internal and external senses, it 
 has unlimited power of mixing, compounding, separ- 
 ating, and dividing these ideas, in all the varieties of 
 fiction and vision. It can feign a train of events, with 
 all the appearance of reality, ascribe to them a partic- 
 
I 
 
 48 AN ENQ UIR Y CONCERNING 
 
 ular time and place, conceive them as existent, and 
 paint them out to itself with every circumstance, that 
 belongs to any historical fact, which it believes with 
 the greatest certainty. ' Wherein, therefore, consists 
 the difference between such a fiction and belief?; It 
 lies not merely in any peculiar idea, which is annexed 
 to such a conception as commands our assent, and 
 which is wanting to every known fiction. For as the 
 mind has authority over all its ideas, it could volun- 
 tarily annex this particular idea to any fiction, and con- 
 sequently be able to believe whatever it pleases ; con- 
 trary to what we find by daily experience. We can, in 
 our conception, join the head of a man to the body of 
 a horse ; but it is not in our power to believe that such 
 an animal has ever really existed. 
 
 It follows, therefore, that (the difference between 
 action and belief' lies in some sentiment or feeling, 
 which is annexed to the latter, not to the former, and 
 which depends not on the will, nor can be commanded 
 at pleasure. It must be excited by nature, like all 
 other sentiments; and must arise from the particular 
 situation, in which the mind is placed at any particu- 
 lar juncture.\\ Whenever any object is presented to the 
 memory or senses, it immediately, by the force of cus- 
 tom, carries the imagination to conceive that object, 
 which is usually conjoined to it ; and this conception 
 is attended with a feeling or sentiment, different from 
 the loose reveries of the fancy. In this consists the 
 whole nature of belief. For as there is no matter of 
 fact which we believe so firmly that we cannot con- 
 ceive the contrary, there would be no difference be- 
 tween the conception assented to and that which is 
 rejected, were it not for some senrtment which dis- 
 tinguishes the one from the other. If I see a billiard- 
 
HUMAN UNDERSTANDING, 49 
 
 ball moving towards another, on a smooth table, I can 
 easily conceive it to stop upon contact. This concep- 
 tion implies no contradiction ; but still it feels very 
 differently from that conception by which I represent 
 to myself the impulse and the communication of mo- 
 tion from one ball to another. 
 
 Were we to attempt a definiiion of this sentiment, 
 we should, perhaps, find it a very difficult, if not an 
 impossible task ; in the same manner as if we should 
 endeavour to define the feeling of cold or passion of 
 anger, to a creature who never had any experience of 
 these sentiments. Belief is the true and proper nameZL tf* 
 of this feeling; and no one is ever at a loss to know 1 ^ 
 the-meaning of that term ; because every man is every j ^ 
 
 moment conscious of the sentiment represented by it. J rs • U 
 It may not, however, be improper to attempt a descrip- 
 tion of this sentiment ; in hopes we may, by that means, 
 arrive at some analogies*, which may afford a more 
 perfect explication of it. I say, then, that belief is 
 nothing but a more vivid, lively, forcible, firm, steady 
 conception of an object, than what the imagination | 
 alone is ever able to attain. This variety of terms,' 
 which may seem so unphilosophical, is intended only 
 to express that act of the mind, which renders realities, 
 or what Is taken for such, more present to us than fic" 
 tions, causes them to weigh more in the thought, and 
 gives them a superior influence on the passions and 
 imagination. Provided we agree about the thing, it is 
 needless to dispute about the terms. The Imagination 
 has the command over all its ideas, and can join and 
 mix and vary them, in all the ways possible. It may 
 concerve fictitious objects with all the circumstances 
 of place and time. It may set them, in a manner, be- 
 fore our eyes, in their true colours, just as they might 
 
50 AN ENQUIRY CONCERNING 
 
 have existed. But as it is impossible that this faculty 
 of imagination can ever, of itself, reach belief, it is 
 evident that belief consists not in the peculiar nature 
 or order of ideas, but in the manner of their concep- 
 tion, and in \kiQ\t feeling to the mind. I confess, that 
 it is impossible perfectly to explain this feeling or 
 manner of conception. We may make use of words 
 which express something near it. But its true and 
 proper name, as we observed before, is belief \ which 
 is a term that every one sufficiently understands in 
 common life, ^nd in philosophy, we can go no farther 
 I than assert, that belief is something felt by the mind, 
 J \ which distinguishes the ideas of the judgement from the 
 fictions of the imagination. It gives them more weight 
 and influence ; makes them appear of greater impor- 
 tance ; enforces them in the mind ; and renders them 
 the governing principle of our actions. I hear at pres- 
 ent, for instance, a person's voice, with whom I am 
 acquainted ; and the sound come^ as from the next 
 room. This impression of my senses immediately con- 
 veys my thought to the person, together with all the 
 surrounding objects. I paint them out to myself as 
 existing at present, with the same qualities and rela- 
 tions, of which I formerly knew them possessed. 
 These ideas take faster hold of my mind than ideas of 
 an enchanted castle. They are very different to the 
 feeling, and have a much greater influence of every 
 kind, either to give pleasure or pain, joy or sorrow. 
 Let us, then, take in the whole compass of this 
 doctrine, and allow, that the sentiment of belief is 
 nothing but a conception more intense and steady than 
 what attends the mere fictions of the imagination, an(f 
 that this manner of conception arises from a customary 
 conjunction of the object with something present to 
 
HUMAN UNDERSTANDING. 51 
 
 the memory or senses : I believe that it will not be 
 difficult, upon these suppositions, to find other opera- 
 tions of the mind analogous to it, and to trace up these 
 phenomena to principles still more general. 
 
 We have already observed that nature has estab- 
 lished connexions among particular ideas^ and that no 
 sooner one idea occurs to our thoughts than it intro- 
 duces its correlative, and carries our attention towards 
 it, by a gentle and insensible movement. These prin- 
 ciples of connexion or association we have reduced to 
 three, namely, Resemblance, Contiguity and Causation; 
 which are the only bonds that unite our thoughts to- 
 gether, and beget that regular train of reflection or 
 discourse, which, in a greater or less degree, takes 
 place among mankind. Now here arises a question, 
 on which the solution of the present difficulty will de- 
 pend. Does it happen, in all these relations, that, 
 when one of the objects is presented to the senses or 
 memory, the mind is not only carried to the concep- 
 tion of the correlative, but reaches a steadier and 
 stronger conception of it than what otherwise it would 
 have been able to attain ? This seems to be the case 
 with that belief which arises from the relation of cause 
 and effect. And if the case be the same with the other 
 relations or principles of associations, this may be es- 
 tablished as a general law, which takes place in all the 
 operations of the mind. 
 
 We may, therefore, observe, as the first experiment 
 to our present purpose, that, upon the appearance of 
 the picture of an absent friend, our idea of him is evi- 
 dently evAvfenedL hyi^Q resemblance, and that every 
 passion, which that idea occasions, whether of joy or 
 sorrow, acquires new force and vigour. In producing 
 this effect, there concur both a relation and a present 
 
52 AN ENQUIRY CONCERNING 
 
 impression. Where the picture bears him no resem- 
 blance, at least was not intended for him, it never so 
 much as conveys our thought to him : And where it 
 * is absent, as well as the person, though the mind may 
 pass from the thought of the one to that of the other, 
 it feels its idea to be rather weakened than enlivened 
 by that transition. We take a pleasure in viewing the 
 picture of a friend, when it is set before us ; but when 
 it is removed, rather choose to consider him directly 
 than by reflection in an image, which is equally distant 
 and obscure, 
 x-^ The ceremonies of the Roman Catholic religion 
 may be considered as instances of the same nature. 
 The devotees of that superstition usually plead in ex- 
 cuse for the mummeries, with which they were up- 
 braided, that they feel the good effect of those exter- 
 nal motions, and postures, and actions, in enlivening 
 their devotion and quickening their fervour, which 
 otherwise would decay, if directed entirely to distant 
 and immaterial objects. We shadow out the objects 
 of our faith, say they, in sensible types and images, 
 and render them more present to us by the immediate 
 presence of these types, than it is' possible for us to do 
 merely by an intellectual view and contemplation. 
 Sensible objects have always a greater influence on the 
 fancy than any other; and this influence they readily 
 convey to those ideas to which they are related, and 
 which they resemble. I shall only infer from these 
 practices, and this reasoning, that the effect of resem- 
 blance in enlivening the ideas is very common ; and 
 as in every case a resemblance and a present impres- 
 sion must concur, we are abundantly supplied with 
 experiments to prove the realit}^ of the foregoing prin- 
 ciple. 
 
HUMAN- UNDERSTANDING. 
 
 53 
 
 We may add force to these experiments by others 
 of a different kind, in considering the effects of contig- 
 uity as well as of resemblance. It is certain that dis- 
 tance diminishes the force of every idea, and that, 
 upon our approach to any object ; though it does not 
 discover itself to our senses ; it operates upon the mind 
 with an influence, which imitates an immediate im- 
 pression. The thinking on any object readily trans- 
 ports the mind to what is contiguous ; but it is only 
 the actual presence of an object, that transports it with 
 a superior vivacity. When I am a few miles from i 
 home, whatever relates to it touches me more nearly 
 than when I am two hundred leagues distant ; though 
 even at that distance the reflecting on any thing in the 
 neighbourhood of my friends or family naturally pro- 
 duces an idea of them. But as in this latter case, both 
 the objects of the mind are ideas; notwithstanding 
 there is an easy transition between them ; that transi- 
 tion alone is not able to give a superior vivacity to any 
 of the ideas, for want of some immediate impression.^ 
 
 No one can doubt but causation has the same in- 
 fluence as the other two relations of resemblance and 
 contiguity. Superstitious people are fond of the rel- 
 iques of saints and holy men, for the same reason, that 
 they seek after types or images, in order to enliven 
 
 1 ' Naturane nobis, inquit, datum dicam, an errore quodam, ut, cum ea 
 loca videamus, in quibus memoria dignos viros acceperimus multum esse 
 versatos, magis moveamur, quam siquando eorum ipsorum aut facta audiamus 
 aut scriptum aliquod legamus ? Velut ego nunc moveor. Venit enim mihi 
 Plato in mentem, quem accepimus primum hie disputare solitum: cuius etiam 
 illi hortuH propinqui non memoriam solum mihi afferunt, sed ipsum videntur 
 in conspectu meo hie ponere. Hie Speusippus, hie Xenocrates, hie eius 
 auditor Polemo ; cuius ipsa ilia sessio fuit, quam videmus. Equidem etiam 
 curiam nostram, Hostiliam dico, non hane novam, quae mihi minor esse 
 videtur postquam est maior, solebam intuens, Scipionem, Catonem, Laeliuml 
 nostrum vero in primis avum cogitare. Tanta vis admonitionis est in locis; 
 ut non sine causa ex his memoriae deducta sit disciplina.' 
 
 Cicero de Finibus. Lib. v. 
 
54 AN ENQUIRY CONCERNING 
 
 their devotion, and give them a more intimate and 
 strong conception of those exemplary lives, which they 
 desire to imitate. Now it is evident, that one of the 
 best reliques, which a devotee could procure, would 
 be the handywork of a saint ; and if his cloaths and 
 furniture are ever to be considered in this light, it is 
 because they were once at his disposal, and were moved 
 and affected by him ; in which respect they are to be 
 considered as imperfect effects, and as connected with 
 him by a shorter chain of consequences than any of 
 those, by which we learn the reality of his existence. 
 
 Suppose, that the son of a friend, who had been 
 long dead or absent, were presented to us; it is evi- 
 dent, that this object would instantly revive its corre- 
 lative idea, and recall to our thoughts all past intima- 
 cies and familiarities, in more lively colours than they 
 would otherwise have appeared to us. This is another 
 phaenomenon, which seems to prove the principle 
 above mentioned. 
 
 We may observe, that, in these phaenomena, the 
 belief of the correlative object is always presupposed; 
 without which the relation could have no effect. The 
 influence of the picture suppose^ that we believe our 
 friend to have once existed. CofJf^ity to home can 
 never excite our ideas of home, unless we believe that 
 it really exists. Now I assert, that this belief, where 
 it reaches beyond the memory or senses, is of a simi- 
 lar nature, and arises from similar causes, with the 
 transition of thought and vivacity of conception here 
 explained. When I throw a piece of dry wood into a 
 fire, my mind is immediately carried to conceive, that 
 it augments, not extinguishes the flame. This transi- 
 tion of thought from the cause to the effect proceeds 
 not from reason. It derives its origin altogether from 
 
HUMAN UNDERSTANDING, 55 
 
 custom and experience. And as it first begins from an 
 object, present to the senses, it renders the idea or con- 
 ception of flame more strong and lively than any loose, 
 floating reverie of the imagination. That idea arises 
 immediately. The thought moves instantly towards 
 it, and conveys to it all that force of conception, which 
 is derived from the impression present to the senses. 
 When a sword is levelled at my breast, does not the 
 idea of wound and pain strike me more strongly, than 
 when a glass of wine is presented to me, even though 
 by accident this idea should occur after the appearance 
 of the latter object ? But what is there in this whole 
 matter to cause such a strong conception, except only 
 a present object and a customary transition to the idea 
 of another object, which we have been accustomed to 
 conjoin with the former ? This is the whole operation 
 of the mind, in all our conclusions concerning matter 
 of fact and existence ; and it is a satisfaction to find 
 some analogies, by which it may be explained. The"~~j 
 transition from a present object does in all cases give \ 
 strength and solidity to the related idea. 
 
 Here, then, is a kind of pre-established harmony *^ 
 between the course of nature and the succession of 
 our i^easy and though the powers and forces, by which 
 the former is governed, be wholly unknown to us ; yet 
 our thoughts and conceptions have still, we find, 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 those objects, commonly conjoined with it, all our 
 knowledge must have been limited to the narrow sphere 
 
a 
 
 56 AAT ENQ UIR Y CONCERNING 
 
 of our memory and senses ; and we should never have 
 been able to adjust means to ends, or employ our nat- 
 ural powers, either to the producing of good, or avoid- 
 ing of evil. Those, who delight in the discovery and 
 contemplation oi final causes, have here ample subject 
 to employ their wonder and admiration. 
 
 I shall add, for a further confirmation of the fore- 
 going theory, that, as this operation of the mind, by 
 which we infer like effects from like causes, and vice 
 versa, is so essential to the subsistence of all human 
 creatures, it is not probable, that 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 wis- 
 dom of nature to secure so necessary an act of the 
 mind, by some instinct or mechanical tendency, which 
 may be infallible in its operations, may discover itself 
 at the first appearance of life and thought, and may 
 be independent of all the laboured deductions of the 
 understanding. 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 for- 
 ward 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 
 V totally depends. 
 
 4% '■ ^ 
 
 
SECTION VI. 
 
 OF PROBABILITY. 1 
 
 j 
 
 THOUGH there be no siich thing as Chance in the 
 world; our ignorance of the real cause of any 
 event has the same influence on the understanding, 
 and begets a like species of belief or opinion. 
 
 There is certainly a probability, which arises from 
 a superiority of chances on any side ; and according 
 as this superiority encreases, and surpasses the oppo- 
 site chances, the probability receives a proportionable 
 encrease, and begets still a higher degree of belief or 
 assent to that side, in which we discover the superior- 
 ity. If a dye were marked with one figure or number 
 of spots on four sides, and with another figure or num- 
 ber of spots on the two remaining sides, it would be 
 more probable, that the former would turn up than 
 the latter ; though, if it had a thousand sides marked 
 in the same manner, and only one side different, the 
 probability would be much higher, and our belief or 
 expectation of the event more steady and secure. This 
 process of the thought or reasoning may seem trivial 
 and obvious ; but to those who consider it more nar- 
 
 1 Mr. Locke divides all arguments into demonstrative and probable. In 
 this view, we must say, that it is only probable all men must die, or that the 
 sun will rise to-morrow. But to conform our language more to common use, 
 we ought to divide arguments into demonstrations, proofs, and probabilities. 
 By proofs meaning such arguments from experience as leave no room for 
 doubt or opposition. 
 
58 AN ENQ UIR V CONCERNING 
 
 rowly, it may, perhaps, afford matter for curious spec- 
 ulation. 
 
 It seems evident, that, when the mind looks for- 
 ward to discover the event, which may result from the 
 throw of such a dye, it considers the turning up of 
 each particular side as alike probable ; and this is the 
 very nature of chance, to render all the particular 
 events, comprehended in it, entirely equal. But find- 
 ing a greater number of sides concur in the one event 
 than in the other, the mind is carried more frequently 
 to that event, and meets it oftener, in revolving the 
 various possibilities or chances, on which the ultimate 
 result depends. This concurrence of several views in 
 one particular event begets immediately, by an irtex- 
 plicable contrivance of nature, the sentiment of belief, 
 and gives that event the advantage over its antagonist, 
 which is supported by a smaller number of views, and 
 recurs less frequently to the mind. If we allow, that 
 belief is nothing but a firmer and stronger conception 
 of an object than what attends the mere fictions of the 
 imagination, this operation may, perhaps, in some 
 measure, be accounted for. The concurrence of these 
 several views or glimpses imprints the idea more 
 strongly on the imagination; gives it superior force 
 and vigour ; renders its influence on the passions and 
 affections more sensible ; and in a word, begets that 
 reliance or security, which constitutes the nature of 
 belief and opinion. 
 
 The case is the same with the p robability of causes , 
 as with that of chance. There are some causes, which 
 are entirely uniform and constant in producing a par- 
 ticular effect ; and no instance has ever yet been found 
 of any failure or irregularity in their operation. Fire 
 has always burned, and water suffocated every human 
 
HUMAN UNDERSTANDING. 59 
 
 creature : The production of motion by impulse and 
 gravity is an universal law, which has hitherto admit- 
 ted of no exception. But there are other causes 
 which have been found more irregular and uncertain; 
 nor has rhubarb always proved a purge, or opium a 
 soporific to every one, who has taken these medicines. 
 It is true, when any cause fails of producing its usual 
 effect, philosophers ascribe not this to any irregularity 
 'n nature; but suppose, that some secret causes, in the 
 particular structure of parts, have prevented the op- 
 eration. Our reasonings, however, and conclusions 
 concerning the event are the same as if this principle 
 had no place. Being determined by custom to transfer 
 the past to the future, in all our inferences ; where 
 the past has been entirely regular and uniform, we ex- 
 pect the event with the greatest assurance, and leave 
 no room for any contrary supposition. But where 
 different effects have been found to follow from 
 causes, which are to appearance exactly similar, all 
 these various effects must occur to the mind in trans- 
 ferring the past to the future, and enter into our con- 
 sideration, when we determine the probability of the 
 event. Though we give the preference to that which/ 
 has been found most usual, and believe that this effect/ 
 will exist, we must not overlook the other effects, but 
 must assign to each of them a particular weight and 
 authority, in proportion as we have found it to be more 
 or less frequent. It is more probable, in almost everj 
 country of Europe, that there will be frost sometime 
 in January, than that the weather will continue oper 
 throughout the whole month ; though this probability 
 varies according to the different climates, and ap- 
 proaches to a certainty in the more northern kingdoms. 
 Here then it seems evident, that, when we transfer the ) 
 
6o AI^ ENQUIRY CONCERNING 
 
 I past to the future, in order to determine the effect, 
 
 I which will result from any cause, we transfer all the 
 
 \ different events, in the same proportion as they have 
 
 vappeared in the past, and conceive one to have existed 
 
 a hundred times, for instance, another ten times, and 
 
 another once. As a great number of views do here 
 
 1 concur in one event, they fortify and confirm it to the 
 limagination, beget that sentiment which we call beliefs 
 and give its object the preference above the contrary 
 f event, which is not supported by an equal number of 
 experiments, and recurs not so frequently to the 
 thought in transferring the past to the future. Let 
 any one try to account for this operation of the mind 
 upon any of the received systems of philosophy, and 
 he will be sensible of the difficulty. For my part, I 
 shall think it sufficient, if the present hints excite the 
 curiosity of philosophers, and make them sensible 
 how defective all common theories are in treating of 
 such curious and such sublime subjects. 
 
SECTION VII, 
 
 OF THE IDEA OF NECESSARY CONNEXION. 
 Part I. 
 
 THE great advantage of the mathematical sciences 
 above the moral consists in this, that the ideas of 
 the former, being sensible, are always clear and deter- 
 minate, the smallest distinction between them is im- '^ 
 mediately perceptible, and the same terms are still N^v^ 
 expressive of the same ideas, without ambiguity oru^ ^ 
 variation. An oval is never mistaken for a circle, nor ^^ 
 an hyperbola for an ellipsis. The isosceles and scale-^N^"- * 
 num are distinguished by boundaries more exact than r ^*^^i 
 vice and virtue, right and wrong. If any term be de- -ir y 
 fined in geometry, the mind readily, of itself, substi- v /^ 
 tutes, on all occasions, the definition for the term de- 
 fined : Or even when no definition is employed, the 
 object itself may be presented to the senses, and by 
 that means be steadily and clearly apprehended. But 
 the finer sentiments of the mind, the operations of the 
 understanding, the various agitations of the passions, 
 though really in themselves distinct, easily escape us, 
 when surveyed by reflection ; nor is it in our power to 
 recall the original object, as often as we have occasion 
 to contemplate it. Ambiguity, by this means, is grad- 
 ually introduced into our reasonings : Similar objects 
 are readily taken to be the same : And the conclusion 
 becomes at last very wide of the premises. 
 
62 AN ENQUIRY CONCERNING 
 
 One may safely, however, affirm, that, if we con- 
 sider these sciences in a proper light, their advantages 
 and disadvantages nearly compensate each other, and 
 reduce both of them to a state of equality. If the 
 mind, with greater facility, retains the ideas of geom- 
 etry clear and determinate, it must carry on a much 
 longer and more intricate chain of reasoning, and 
 compare ideas much wider of each other, in order to 
 reach the abstruser truths of that science. And if 
 moral ideas are apt, without extreme care, to fall into 
 obscurity and confusion, the inferences are always 
 much shorter in these disquisitions, and the interme- 
 diate steps, which lead to the conclusion, much fewer 
 than in the sciences which treat of quantity and num- 
 ber. In reality, there is scarcely a proposition in 
 Euclid so simple, as not to consist of more parts, than 
 are to be found in any moral reasoning which runs not 
 into chimera and conceit.. Where we trace the prin- 
 ciples of the human mind through a few steps, we may 
 be very well satisfied with our progress ; considering 
 how soon nature throws a bar to all our enquiries con- 
 cerning causes, and reduces us to an acknowledgment 
 pi' of our ignorance. l^The chief obstacle, therefore, to 
 \ our improvement in the moral or metaphysical sci- 
 jl ences is the obscurity of the ideas, and ambiguity of 
 >"l!j the terms^The principal difficulty in the mathematics 
 ' I is the length of inferences and compass of thought, 
 requisite to the forming of any conclusion. And, per- 
 haps, our progress in natural philosophy is chiefly re- 
 tarded by the want of proper experiments and phae- 
 nomena, which are often discovered by chance, and 
 cannot always be found, when requisite, even by the 
 most diligent and prudent enquiry. As moral philos- 
 ophy seems hitherto to have received less improve- 
 
HUMAN UNDERSTANDING. O3 
 
 ment than either geometry or physics, we may con- 
 clude, that, if there be any difference in this respect 
 among these sciences, the difficulties, which obstruct 
 the progress of the former, require superior care and 
 capacity to be surmounted. 
 
 There are no ideas, which occur in metaphysics,] 
 more obscure and uncertain, than those oi power, force, \ 
 energy or necessary connexion, of which it is every mom-! 
 ent necessary for us to treat in all our disquisitions. 
 We shall, therefore, endeavour, in this section, to fix, 
 if possible, the precise meaning of these terms, and 
 thereby remove some part of that obscurity, which is 
 so much complained of in this species of philosophy. 
 It seems a proposition, which will not admit of 
 much dispute, that all our ideas are nothing but copies 
 of our impressions, or, in other words, that it is impos- 
 sible for us to think of any thing, which we have not ante- 
 cedently/^//, either by our external or internal senses. 
 I have endeavoured 1 to explain and prove this propo- 
 sition, and have expressed my hopes, that, by a proper 
 application of it, men may reach a greater clearness 
 and precision in philosophical reasonings, than what 
 they have hitherto been able to attain. Complex ici^as 
 may, perhaps, be well known by definition, which is 
 nothing but an enumeration of those parts or simple 
 ideasTthat compose them. But when we have pushed 
 up definitions to the most simple ideas, and find still 
 some ambiguity and obscurity ; what resource are we 
 then possessed of ? By what invention can we throw 
 light upon these ideas, and render them altogether 
 precise and determinate to our intellectual view ? 
 /Produce the impressions or original sentiments, from 
 ' which the ideas are copied. These impressions are al 1 
 
 1 Section II. ' 
 
64 AN ENQUIRY CONCERNING 
 
 Strong and sensible. They admit not of ambiguity. 
 They are not only placed in a full light themselves, 
 but may throw light on their correspondent ideas, 
 which lie in obscurity. And by this means, we may, 
 perhaps, attain a new microscope or species of optics, 
 by which, in the moral sciences, the most minute, and 
 most simple ideas may be so enlarged as to fall readily 
 
 I under our apprehension, and be equally known with 
 
 ! the grossest and most sensible ideas, that can be the 
 
 1 object of our enquiry. 
 
 To be fully acquainted, therefore, with the idea of 
 power pxJie^^essary connexion, let us examine its im- 
 pressionj and in order to find the irnpTessioh wltH' 
 greater certainty, let us search for it in all the sources, 
 from which it may possibly be derived. 
 
 r When we look about us towards external objects, 
 and consider the operation of causes, we are never 
 able, in a single instance, to discover any power or 
 necessary connexion ; any quality, which binds the 
 effect to the cause, and renders the one an infallible 
 consequence of the other. We only find, that the one 
 does actually, in fact, follow the other. The impulse 
 of one billiard-ball is attended with motion in the sec- 
 ond. This is the whole that appears to the outward 
 senses. The mind feels no sentiment or inward im- 
 pression from this succession of objects : Consequently 
 there is not, in any single, particular instance of cause 
 and effect, any thing which can suggest the idea of 
 power or necessary connexion. 
 
 From the first appearance of an object, we never 
 can conjecture what effect will result from it. But 
 were the power or energy of any cause discoverable 
 by the mind, we could foresee the effect, even without 
 experience ; and might, at first, pronounce with cer- 
 
HUMAN UNDERSTANDING. 65 
 
 talnty concerning it, by mere dint of thought and rea- 
 soning. 
 
 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 any thing, or be followed by any other object, 
 which we could denominate its effect. Solidity, exten-^ 
 sion, motion ; these qualities are all complete in them- 
 selves, and never poipt out any other event which may 
 result from them. \The scenes of the universe are con- 
 tinually shifting, and one object follows another in an 
 uninterrupted succession; but /the power of force, m 
 which actuates the whole machine, is entirely con- 
 cealed from us, and never discovers itself in any of the 
 sensible qualities of bo^yj We know, that, in fact, 
 heat is a constant attendant of flame ; but what is the 
 connexion between them, we have no room so much 
 as to conjecture or imagine. It is impossible, there- 
 fore, that the idea of power can be derived from the 
 contemplation of bodies, in single instances of their 
 operation ; because no bodies ever discover any power, 
 which can be the original of this idea.^ 
 
 Since, therefore, external objects as they appear to 
 the senses, give us no idea of power or necessary con- 
 nexion, by their operation in particular instances, let 
 us see, whether this idea be derived from reflexion on 
 the operations of our own minds, and be copied from 
 any internal impression. It may be said, that we are 
 every moment conscious of internal power; while we 
 
 1 Mr. Locke, in his chapter of power, says, that, finding from experience, \ 
 that there are several new productions in matter, and concluding that there ' 
 must somewhere be a power capable of producing them, we arrive at last by 
 this reasoning at the idea of power. But no reasoning can ever give us a new» 
 original, simple idea; as this philosopher himself confesses. This, therefore, 1 
 can never be the origin of that idea. 
 
66 AN ENQUIRY CONCERNING 
 
 *eel, that, by the simple command of our will, we can 
 move the organs of our body, or direct the faculties of 
 our mind. An act of volition produces motion in our 
 limbs, or raises a new idea in our imagination. This 
 influence of the will we know by consciousness. Hence 
 we acquire the idea of power or energy ; and are cer- 
 tain, that we ourselves and all other intelligent beings 
 are possessed of power. This idea, then, is an idea 
 of reflection, since it arises from reflecting on the op- 
 erations of our own mind, and on the command which 
 is exercised by will, both over the organs of the body 
 and faculties of the soul. 
 
 We shall proceed to examine this pretension ; and 
 first with regard to the influence of volition over the 
 organs of the body. This influence, we may observe, 
 is a fact, which, like all other natural events, can be 
 known only by experience, and can never be foreseen 
 from any apparent energy or power in the cause, which 
 connects it with the effect, and renders the one an in- 
 fallible consequence of the other. The motion of our 
 body follows upon the command of our will. Of this 
 we are every moment conscious. But the means, by 
 which 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. 
 j Yoxjirsi'y is there jjiy principle in all nature more 
 lHjisterionajthanjhe union of soul with body; by which 
 a supposed spiritual substance acquires such an influ- 
 ence over a material one, that the most refined thought 
 is able to actuate the grossest matter ? Were we em- 
 powered, by a secret wish, to remove mountains, or 
 control the planets in their orbit j this extensive au- 
 thority would not be more extraordinary, nor more 
 
HUMAN- UNDERSTANDING. 67 
 
 beyond our comprehension. But if by consciousness 
 we perceived any power or energy in the will, we must 
 know this power; we must know its connexion with 
 the effect ; we must know the secret union of soul and 
 body, and the nature of both these substances; by 
 which the one is able to operate, in so many instances, 
 upon the other. 
 
 ^^^^;?^/y^ Wejire^not able to move all the organs of 
 the body with a like authority ; though we cannot as- 
 sign any reason besides experience, for so remarkable 
 a difference between one and the other. Why has the 
 will an influence over the tongue and fingers, not over 
 the heart and liver ? This question would never em- 
 barrass us, were we conscious of a power in the former 
 case, not in the latter. We should then perceive, in- 
 dependent of experience, why the authority of will 
 over the organs of the body is circumscribed within 
 such particular limits. Being in that case fully ac- 
 quainted with the power or force, by which it operates, 
 we should also know, why its influence reaches pre- 
 cisely to such boundaries, and no farther. 
 
 Ajnan, suddenly struck with palsy in the leg or 
 arm, or who had newly lost those members, frequently 
 endeavours, at first to move them, and employ them in 
 t heir u sual offices. Here he is as much conscious of 
 power to command such limbs, as a man in perfect 
 health is conscious of power to actuate any member 
 which remains in its natural state and condition. But 
 consciousness never deceives. Consequently, neither 
 in the one case ^or in the other, are we ever conscious 
 of any power, f ^ye learn the influence of our will from 
 experience alone. And experience only, teaches us, 
 how one event constantly follows another; without 
 
68 AN- ENQUIRY CONCERNING 
 
 instructing us in the secret connexion, which binds 
 them together, and renders them inseparable. 
 
 Thirdly, We learn from anatomy, that the immedi- 
 ate object of power in voluntary motion, is not the 
 member itself which is moved, but certain muscles, 
 and nerves, and animal spirits, and, perhaps, some- 
 thing still more minute and more unknown, through 
 which the motion is successfully propagated, ere it 
 reach the member itself whose motion is the immediate 
 object of volition. Can there be a more certain proof 
 that the power, by which this whole operation is per- 
 formed, so far froni being directly and fully known by 
 an inward sentiment or consciousness, is, to the last 
 degree, mysterious and unintelligible ? Here the mind 
 wills a certain event : Immediately another event, un- 
 known to ourselves, and totally different from the one 
 intended, is produced ; This event produces another, 
 equally unknown : Till at last, through a long succes- 
 sion, the desired event is produced. But if the original 
 power were felt, it must be known : Were it known, 
 its effect also must be known ; since all power is rela- 
 tive to its effect. And vice versa, if the effect, be not 
 known, the power cannot be known nor felt. How in- 
 deed can we be conscious of a power to move our limbs, 
 when we have no such power \ but only that to move 
 certain animal spirits, which, though they produce at 
 last the motion of our limbs, yet operate in such a 
 manner as is wholly beyond our comprehension ? 
 
 We may, therefore, conclude from the whole, I 
 hope, without any temerity, though with assurance; 
 that our idea of power is not copied from any senti- 
 ment or consciousness of power within ourselves, when 
 we give rise to animal motion, or apply our limbs, to 
 1 their proper use and office. That their motion follows 
 
HUMAN UNDERSTANDING, 69 
 
 the command of the will is a matter of common expe- 
 rience, like other natural events : But the power or 
 energy by which this is effected, like that in other 
 natural events, is unknown and inconceivable.^ 
 
 Shall we then assert, that we are conscious of a 
 power or energy in our 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? 
 I believe the same arguments will prove, that even 
 this command of the will gives us no real idea of force 
 or energy. 
 
 Firsts It must be allowed, that, when we know a \ 
 power, we know that very circumstance in the cause, j 
 by which it is enabled to produce the effect : For thesej 
 are supposed to be synonimous. We must, therefore, 
 know both the cause and effect, and the relation be- 
 tween them. 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? This 
 is a real creation ; a production of something out of 
 nothing : Which implies a power so great, that it may 
 
 1 It may be pretended, that the resistance which we meet with in bodies, 
 obliging us frequently to exert our force, and call up all our power, this gives 
 us the idea of force and power. It is this nisus, or strong endeavour, of which 
 we are conscious, that is the original impression from which this idea is cop- 
 ied. But, first, we attribute power to a vast number of objects, where we never 
 can suppose this resistance or exertion of force to take place ; to the Supreme 
 Being, who never meets with any resistance ; to the mind in its command 
 over its ideas and limbs, in common thinking and motion, where the effect 
 follows immediately upon the will, without any exertion or summoning up of 
 force ; to inanimate matter, which is not capable of this sentiment. Secondly, 
 This sentiment of an endeavour to overcome resistance has no known con- 
 nexion with any event : What follows it, we know by experience; but could 
 not know it h priori. It must, however, be confessed, that the animal nisus^ 
 which we experience, though it can aflford no accurate precise idea of power, 
 enters very much into that vulgar, inaccurate idea, which is formed of ito 
 
70 AN ENQ UIR V CONCERNING 
 
 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 conceiv- 
 able by the mind. We only feel the event, namely, 
 the existence of an idea, consequent to a command of 
 the will : But the manner, in which this operation is 
 performed, the power by which it is produced, is en- 
 tirely beyond our comprehension. T 
 
 Secondly^ The command of the mind over itself is 
 limited, as well as its command over the body ; and 
 these limits are not known by reason, or any acquain- 
 tance with the nature of cause and effect, but only by 
 experience and observation, as in all other natural 
 events and in the operation of external objects. Our 
 authority over our sentiments and passions is much 
 weaker than that over our ideas ; and even the latter 
 authority is circumscribed within very narrow bound- 
 aries. Will any one pretend to assign the ultimate 
 reason of these boundaries, or show why the power is 
 deficient in one case, not in another. 
 
 Thirdly y This self-command is very different at dif- 
 ferent 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 ev- 
 ening : Fasting, than after a full meal. Can we give 
 any reason for these variations, except experience ? 
 Where then is the power, of which we pretend to be 
 conscious ? Is there not here, either in a spiritual or 
 material substance, or both, some secret mechanism 
 or structure of parts, upon which the effect depends, 
 and which, being entirely unknown to us, renders the 
 power or energy of the will equally unknown and 
 incomprehensible ? 
 
 Volition is surely an act of the mind, with which 
 
/ 
 
 HUMAN UNDERSTANDING. 71 
 
 we are sufficiently acquainted. Reflect upon it. Con- 
 sider it on all sides. Do you find anything in it like 
 this creative power, by which it raises from nothing a 
 new idea, and with a kind of Fiat^ imitates the omni- 
 potence of its Maker, if I may be allowed so to speak, 
 who called forth into existence all the various scenes 
 of nature ? So far from being conscious of this energy 
 in the will, it requires as certain experience as that of 
 which we are possessed, to convince us that such ex- 
 traordinary effects do ever result from a simple act of 
 volition. 
 
 The generality of mankind never find any difficulty 
 in accounting for the more common and familiar oper- 
 ations of nature — such as the descent of heavy bodies, 
 the growth of plants, the generation of animals, or the 
 nourishment of bodies by food : But suppose that, in 
 all these cases, they perceive the very force or energy 
 of the cause, by which it is connected with its effect, 
 and is for ever infallible in its operation. They ac- 
 quire, by long habit, such a turn of mind, that, upon 
 the appearace of the cause, they immediately expect 
 with assurance its usual attendant, and hardly con- 
 ceive it possible that any other event could result from 
 it. It is only on the discovery of extraordinary phae- 
 nomena, such as earthquakes, pestilence, and prodi- 
 gies of any kind, that they find themselves at a loss 
 to assign a proper cause, and to explain the manner 
 in which the effect is produced by it. It is usual for 
 men, in such difficulties, to have recourse to some in- 
 visible intelligent principle^ as the immediate cause of 
 that event which surprises them, and which, they think, 
 cannot be accounted for from the common powers of 
 nature. But philosophers, who carry their scrutiny a 
 
 1 0e6$ arrb it.ywixvi\^. 
 
4 
 
 72 AN ENQUIRY CONCERNING 
 
 little farther, immediately perceive that, even in the 
 most familiar events, the energy of the cause is as un- 
 intelligible as in the most unusual, and that we only 
 learn by experience the frequent Conjunction of objects, 
 without being ever able to comprehend anything like 
 Connexion between them. Here, then, many philoso- 
 phers think themselves obliged by reason to have re- 
 course, on all occasions, to the same principle, which 
 the vulgar never appeal to but in cases that appear 
 miraculous and supernatural. They acknowledge mind 
 and intelligence to be, not only the ultimate and prig- 
 inal cause of all things, but the immediate and sole 
 cause of every event which appears in nature. They 
 pretend that those objects which are commonly denom- 
 inated causes, are in reality nothing but occasions \ and 
 that the true and direct principle of every effect is not 
 any power or force in nature, but a volition of the 
 Supreme Being, who wills that such particular objects 
 should for ever be conjoined with each other. Instead 
 of saying that one billard-ball moves another by a force 
 which it has derived from the author of nature, it is 
 the Deity himself, they say, who, by a particular voli- 
 tion, moves the second ball, being determined to this 
 operation by the impulse of the first ball, in conse- 
 quence of those general laws which he has laid down 
 to himself in the government of the universe: But 
 philosophers advancing still in their inquiries, discover 
 that, as we are totally ignorant of the power on which 
 depends the mutual operation of bodies, we are no less 
 ignorant of that power on which depends the operation 
 of mind on body, or of body on mind ; nor are we 
 able, either from our senses or consciousness, to assign 
 the ultimate principle in one case more than in the 
 other. The same ignorance, therefore, reduces them 
 
HUMAN- UNDERSTANDING 73 
 
 to the same conclusion. They assert that the Deity 
 is the immediate cause of the union between soul and 
 body ; and that they are not the organs of sense, which, 
 being agitated by external objects, produce sensations 
 in the mind ; but that it is a particular volition of our 
 omnipotent Maker, which excites such a sensation, in 
 consequence of such a motion in the organ. In like 
 manner, it is not any energy in the will that produces 
 local motion in our members : It is God himself, who 
 is pleased to second our will, in itself impotent, and to 
 command that motion which we erroneously attribute 
 to our own power and efficacy. Nor do philosophers 
 st5p at this conclusion. They sometimes extend the 
 same inference to the mind itself, in its internal opera- 
 tions. Our mental vision or conception of ideas is 
 nothing but a revelation riiade to us by our Maker. 
 When we voluntarily turn our thoughts to any object, 
 and raise up its image in the fancy, it is not the will 
 which creates that idea : It is the universal Creator, 
 who discovers it to the mind, and renders it present 
 to us. 
 
 Thus, according to these philosophers, every thing 
 is full of God. Not content with the principle, that 
 nothing exists but by his will, that nothing possesses 
 any power but by his concession : They rob nature, 
 and all created beings, of every power, in order to ren- 
 der their dependence on the Deity still more sensible 
 and immediate. They consider not that, by this the- 
 ory, they diminish, instead of magnifying, the gran- 
 deur of those attributes, which they affect so much to 
 celebrate. It argues surely more power in the Deity 
 to delegate a certain degree of power to inferior crea- 
 tures, than to produce every thing by his own immedi- 
 ate volition. It argues more wisdom to contrive at 
 
74 AN ENQUIRY CONCERNING 
 
 first the fabric of the world with such perfect foresight 
 that, of itself, and by its proper operation, it may serve 
 all the purposes of providence, than if the great Crea- 
 tor were obliged every moment to adjust its parts, and 
 animate by his breath all the wheels of that stupen- 
 dous machine. 
 
 But if we would have a more philosophical confu- 
 tation of this theory, perhaps the two following reflec- 
 tions may suffice. 
 
 First, it seems to me that this\theory of the univer- 
 sal energy and operation of the Supreme Being is too 
 bold ever to carry conviction with it to a man, suffici- 
 ently apprized of the weakness of human reason, and 
 the narrow limits to which it is confined in all its oper- 
 ations. Though the chain of arguments which con- 
 duct to it were ever so logical, there must arise a strong 
 suspicion, if not an absolute assurance, that it has 
 carried us quite beyond the reach of our faculties, 
 when it leads to conclusions so extraordinary, and so 
 remote from common life and experience. We are got 
 into fairy land, long ere we have reached the last steps 
 of our theory ; and there we have no reason to trust 
 our common methods of argument, or to think that 
 our usual analogies and probabilities have any author- 
 ity. Our line is too short to fathom such immense 
 abysses. And however we may flatter ourselves that 
 we are guided, in every step which we take, by a kind 
 of verisimilitude and experience, we may be assured 
 that thfs fancied experience has no authority when we 
 thus apply it to subjects that lie entirely out of the 
 sphere of experience. But on this we shall have oc- 
 casion to touch afterwards.^ 
 
 Secondly, I cannot perceive any force in the argu- 
 
 1 Section XII. 
 
HUMAN UNDERSTANDING 75 
 
 ments on which this theory is founded. We are ig* 
 norant, it is true, of the manner in which bodies oper- 
 ate on each other: Their force or energy is entirely 
 incomprehensible : But are we not equally ignorant 
 of the manner or force hy which a mind, even the su, 
 preme mind, operates either on itself or on body ? 
 Whence, I beseech you, do we acquire any idea of it ? 
 We have no sentiment or consciousness of this power 
 in ourselves. We have no idea of the Supreme Being 
 but what we learn from reflection on our own faculties. 
 Were our ignorance, therefore, a good reason for re- 
 jecting any thing, we st 4d be led into that principle 
 of denying all energy in the w upreme Being as much 
 as in the grossest matter. V 'e surely comprehend as 
 little the operations of on- a^^ of the other. Is it more 
 difficult to conceive that mv.tion may arise from im- 
 pulse than that it may .Ise from volition ? All we 
 know is our profound ignorance in both cases. ^ 
 
 Paf- I. 
 
 But to hasten to a Cr elusion of this argument, 
 which is already drawn out to too great a length : We 
 have sought in vain for i-'-fiiigr of power or necessary 
 connexion in all the souiccs from which we could sup- 
 
 1 1 need not examine at length the vis inertiae which is so much talked of 
 in the new philosophy, and which is ascribed to matter. We find by experi- 
 ence, that a body at rest or in motion continues for ever in its present state, 
 till put from it by some new cause ; and that a body impelled takes as much 
 motion from the impelling body as it acquires itself. These are facts. When 
 we call this a vis inertiae, we only mark these facts, without pretending to 
 have any idea of the inert power; in the same manner as, when we talk of 
 gravity, we mean certain effects, without comprehending that active power. 
 It was never the meaning of Sir Isaac Newton to rob second causes of all 
 force or energy ; though some of his followers have endeavoured to establish 
 that theory upon his authority. On the contrary, that great philosopher had 
 recourse to an etherial active fluid to explain his universal attraction ; though 
 he was so cautious and modest as to allow, that it was a mere hypothesis, not 
 
76 AN ENQUIRY CONCERNING 
 
 pose it to be derived. It appears that, in single in- 
 C \ stances of the operation of bodies, we never can, by 
 ^ > our utmost scrutiny, discover any thing but one event 
 following another, without being able to comprehend 
 ; j any force or power by which the cause operates, or 
 v^ any connexion between it and its supposed effectTi he 
 same difficulty occurs in contemplating the operations 
 of mind on body — where we observe the motion of the 
 latter to follow upon the volition of the former, but 
 are not able to observe or conceive the tie which binds 
 together the motion and volition, or the energy by 
 which the mind produces this effect. The authority 
 of the will over its own faculties and ideas is not a whit 
 more comprehensible : So that, upon the whole, 'there 
 I appears not, throughout all nature, any one instance 
 \ of connexion which is conceivable by us.: All events 
 seem entirely loose and separate. One event follows 
 another; but we never can observe any tie between "^ 
 them. /They seem conjoined, but never connected. J And 
 as we can have no idea of any thing which never ap- 
 peared to our outward sense or inward sentiment, the^__ 
 necessary conclusion seems to be that we have no idea 
 of connexion or power at all, and that these words are 
 absolutely without any meaning, when employed 
 either in philosophical reasonings or common life. 
 
 But there still remains one method of avoiding this 
 conclusion, and one source which we have not yet 
 examined. When any natural object or event is pre- 
 
 to be insisted on, without more experiments. I must confess, that there is 
 something in the fate of opinions a little extraordinary. Des Cartes insinu* 
 ated that doctrine of the universal and sole efficacy of the Deity, without in- 
 sisting on it. Malebranche and other Cartesians made it the foundation of 
 all their philosophy. It had, however, no authority in England. Locke, 
 Clarke, and Cudworth, never so much as take notice of it, but suppose all 
 along, that matter has a real, though subordinate and derived power. By 
 what means has it become so prevalent among our modern metaphysicians ? 
 
HUMAN UNDERSTANDING, 77 
 
 sented, it is impossible for us, by any sagacity or pen- 
 etration, to discover, or even conjecture, without ex- 
 perience, what event will result from it, or to carry 
 our foresight beyond that object which is immediately 
 present to the memory and senses. Even after one 
 instance or experiment where we have observed a par- 
 ticular 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 esteemed an un- 
 pardonable temerity to judge of the whole course of na- 
 ture from one single experiment, however accurate or 
 certain. iBut when one particular species of event has -i 
 always, in all instances, been conjoined with another, \ 
 we make no longer any scruple of foretelling one upon I 
 the appearance of the other, and of employing that ! 
 reasoning which can alone assure us of any matter of j 
 fact or existence. We then call the one object, C^z^j^; 1 
 the other, Effect, We suppose that there is some - \ 
 connexion between them;' some j^jwer in the one, by 
 which it infallibly produces the other, and operates 
 with the greatest certainty and strongest necessity.^ 
 
 It appears, then, that this idea of a necessary con. 
 nexion among events arises from a number of similar 
 instances which occur of the constant conjunction of 
 these events ; nor can that idea ever be suggested by 
 any one of these instances, surveyed in all possible 
 lights and positions. But there is nothing in a num- 
 ber of instances, different from every single instance, 
 which is supposed to be exactly similar ; except only, 
 that after a repetition of similar instances, the mind 
 is carried by habit, upon the appearance of one event, 
 to expect its usual attendant, and to believe that it will 
 exist. This connexion, therefore, which we /<?<?/ in the 
 mind, this customary transition of the imagination 
 
78 AN ENQUIRY CONCERNING 
 
 I from one object to its usual attendant, is the sentiment 
 I or impression from which we form the idea of power 
 i^ or necessary connexion.! Nothing farther is in the 
 case. Contemplate the~subject on all sides ; you will 
 never find any other origin of that idea. This is the 
 sole difference between one instance, from which we 
 can never receive the idea of connexion, and a number 
 of similar instances, by which it is suggested. The first 
 time a man saw the communication of motion by im- 
 pulse, as by the shock of two billiard balls, he could 
 not pronounce that the one event was connected', but 
 only that it was conjoined with the other. After he has 
 observed several instances of this nature, he then pro- 
 nounces them to be connected. What alteration has 
 happened to give rise to this new idea of connexion ? 
 Nothing but that he now Jeels these events to be con- 
 nected in his imagination, and can readily foretell the 
 existence of one from flie appearance of the other. 
 When we say, therefore, that one object is connected 
 with another, we mean only that they have acquired 
 a connexion in our thought, and give rise to this infer- 
 ence, by which they become proofs of each other's ex- 
 istence : A conclusion which is somewhat extraordi- 
 nary, but which seems founded on sufficient evidence. 
 Nor will its evidence be weakened by any general dif- 
 fidence of the understanding, or sceptical suspicion 
 concerning every conclusion which is new and extra- 
 ordinary. No conclusions can be more agreeable to 
 scepticism than such as make discoveries concerning 
 the weakness and narrow limits of human reason and 
 capacity. 
 
 And what stronger instance can be produced of the 
 surprising ignorance and weakness of the understand- 
 ing than the present ? For surely, if there be any re- 
 
HUMAN UNDERSTANDING, 79 
 
 lation 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 existence. By means of it alone we attain any as- 
 surance 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 theTHeas which we form concerning it, 
 that it is impossible to give any just definition of cause, 
 except what is drawn from something extraneous and 
 foreign to it. Similar objects are always conjoined with 
 similar. Of this we have experience. Suitably to this 
 experience, therefore, we may define a cause to be an 
 object y followed by another ^ and where all the objects simi 
 lar to the jirst are followed by objects similar to the second. 
 Or in other words where ^ if the first object had not been, 
 the second never had existed. The appearance of a cause 
 always conveys the mind, by a customary transition, 
 to the idea of the effect. Of this also we have experi- 
 ence. We may, therefore, suitably to this experience, 
 form another definition of cause, and call it, an object 
 followed by another ^ and whose appearance always conveys 
 the thought to that other. But though both these defi- 
 nitions be drawn from circumstances foreign to the 
 cause, we cannot remedy this inconvenience, or attain 
 any more perfect definition, which may point out that 
 circumstance in the cause, which gives it a connexion 
 with its effect. 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 
 
 ) 
 
8o AN ENQ UIR Y CONCERNING 
 
 the cause of this particular sound. But what do we 
 mean by that affirmation ? We either mean that this 
 vibration is followed by this sound, and that all similar 
 vibrations have been followed by similar sounds : Or, that 
 this vibration is followed by this sound, and that upon the 
 appearance 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.^ 
 
 To recapitulate, therefore, the reasonings of this 
 section : Every idea is copied from some preceding 
 impression or sentiment ; and where we cannot find 
 any iippression, we may be certain that there is no 
 Idea.Aln all single instances of the operation of bodies 
 or minds, there is nothing that produces any impres- 
 
 1 According to these explications and definitions, the idea of Power is re- 
 lative as much as that of cause ; and both have a reference to an effect, or 
 some other event constantly conjoined with the former. When we consider 
 the ««^«<7w« circumstance of an object, by which the degree or quantity of 
 its effect is fixed and determined, we call that its power: And accordingly, 
 it is allowed by all philosophers, that the effect is the measure of the power. 
 But if they had any idea of power, as it is in itself, why could not they meas- 
 ure it in itself ? The dispute whether the force of a body in motion be as its 
 velocity, or the square of its velocity; this dispute, I say, needed not be de- 
 cided by comparing its effects in equal or unequal times ; but by a direct 
 mensuration and comparison. 
 
 As to the frequent use of the words, Force, Power, Energy, &c., which ev- 
 ery where occur in common conversation, as well as in philosophy ; that is 
 no proof, that we are acquainted, in any instance, with the connecting_princi« 
 pie between cause and effect, or can account ultimately for the production of 
 one thing to another. These words, as commonly used, have very loose 
 meanings annexed to them; and their ideas are very uncertain and confused. 
 No animal can put external bodies in motion without the sentiment of a nisua 
 or endeavour; and every animal has a sentiment or feeling from the stroke 
 or blow of an external object, that is in motion. These sensations, which are 
 > merely animal, and from which we can h priori draw no inference, we are 
 I apt to transfer to inanimate objects, and to suppose, that they have some such 
 feelings, whenever they transfer or receive motion. With regard to energies, 
 which are exerted, without our annexing to them any idea of communicated 
 motion, we consider only the constant experienced conjunction of the events; 
 and as yj&feel a customary connexion between the ideas, we transfer that 
 feeling to the objects; as nothing is more usual than to apply to external bodies 
 every internal sensation, which they occasion. 
 
HUMAN UNDERSTANDING, 8x 
 
 sion, nor consequently can suggest any idea of power 
 or necessary connexion/^ But when many uniform in- 
 stances appear, and the same object is always followed 
 by the same event; we then begin to entertain the 
 notion of cause and connexion. We then feel a new 
 sentiment or impressson, to wit, a customary connex- 
 ion in the thought or imagination between one object 
 and its usual attendant; and this sentiment is the 
 origin al of that idea which we seek for. For as this 
 idea arises from a number of similar instances, and 
 not from any single instance, it must arise from that cir- 
 cumstance, in which the number of instances differ 
 from every individual instance. But this customary 
 connexion or transition of the imagination is the only 
 circumstance in which they differ. In every other par- 
 ticular they are alike. The first instance which we saw 
 of motion communicated by the shock of two billiard 
 balls (to return to this obvious illustration) is exactly 
 similar to any instance that may, at present, occur to 
 us ; except only, that we could not, at first, infer one 
 event from the other ; which we are enabled to do at 
 present, after so long a course of uniform experience. 
 I know not whether the reader will readily apprehend 
 this reasoning. I am afraid that, should I multiply 
 words about it, or throw it into a greater variety of 
 lights, it would only become more obscure and intri- 
 cate. In all abstract reasonings there is one point of 
 view which, if we can happily hit, we shall go farther 
 towards illustrating the subject than by all the elo- 
 quence in the world. This point of view we should 
 endeavour to reach, and reserve the flowers of rhetoric 
 for subjects which are more adapted to them. 
 
 \ t^"^' 
 
SECTION VIII. 
 
 OF LIBERTY AND NECESSITY, 
 
 Part I. 
 
 FT might reasonably be expected in questions which 
 X have been canvassed and disputed with great eager- 
 ness, since the first origin of science and philosophy, 
 that the meaning of all the terms, at least, should 
 have been agreed upon among the disputants; and 
 our enquiries, in the course of two thousand years, 
 been able to pass from words to the true and real sub- 
 ject of the controversy. For how easy may it seem 
 to give exact definitions of the terms employed in rea- 
 soning, and make these definitions, not the mere sound 
 of words, the object of future scrutiny and examina- 
 tion? But if we consider the matter more narrowly, 
 we shall be apt to draw a quite opposite conclusion. 
 From this circumstance alone, that a controversy has 
 been long kept on foot, and remains still undecided, 
 we may presume that there is some ambiguity in the 
 expression, and that the disputants affix different ideas 
 to the terms employed in the controversy. For as the 
 faculties of the mind are supposed to be naturally alike 
 in every individual ; otherwise nothing could be more 
 fruitless than to reason or dispute together; it were 
 impossible, if men affix the same ideas to their terms, 
 that they could so long form different opinions of the 
 same subject ; especially when they communicate their 
 
HUMAN UNDERSTANDING. 83 
 
 views, and each party turn themselves on all sides, in 
 search of arguments which may give them the victory 
 over their antagonists. It is true, if men attempt the 
 discussion of questions which lie entirely beyond the 
 reach of human capacity, such as those concerning 
 the origin of worlds, or the economy of the intellectual 
 system or region of spirits, they may long beat the air 
 in their fruitless contests, and never arrive at any de- 
 terminate conclusion. But if the question regard any 
 subject of common life and experience, nothing, one 
 would think, could preserve the dispute so long unde- 
 cided but some ambiguous expressions, which keep 
 the antagonists still at a distance, and hinder them 
 from grappling with each other. 
 
 This has been the case in the long disputed ques- 
 tion concerning liberty and necessity ; and to so re- 
 markable a degree that, if I be not much mistaken, 
 we shall find, that all mankind, both learned and ig- 
 norant, have always been of the same opinion with 
 regard to this subject, and that a few intelligible defi- 
 nitions would immediately have put an end to the 
 whole controversy. I own that this dispute has been 
 so much canvassed on all hands, and has led philoso- 
 phers into such a labyrinth of obscure sophistry, that 
 it is no wonder, if a sensible reader indulge his ease 
 so far as to turn a deaf ear to the proposal of such a 
 question, from which he can expect neither instruction 
 nor entertainment. But the state of the argument here 
 proposed may, perhaps, serve to renew his attention ; 
 as it has more novelty, promises at least some decision 
 of the controversy, and will not much disturb his ease 
 by any intricate or obscure reasoning. 
 
 I hope, therefore, to make it appear that all men 
 have ever agreed in the doctrine both of necessity and 
 
»^^ 
 
 84 AN" ENQ UIR V CONCERNING 
 
 ^i liberty, according to any reasonable sense, which 
 / can be put on these terms ; and that/ the whole ^con- 
 troversy has hitherto turned merely upon wordsi \ We 
 shall begin with examining the doctrine of necessity.*) 
 
 ^ It is universally allowed that matter, in all its op- 
 
 erations, is actuated by a necessary force, and that 
 every natural effect is so precisely determined by the 
 energy of its cause that no other effect, in such par- 
 ticular circumstances, could possibly have resulted 
 from it.^ The degree and direction of every motion is, 
 by the laws of nature, prescribed with such exactness 
 that a living creature may as soon arise from the shock 
 of two bodies as motion in any other degree or direc- 
 tion than what is actually produced by it.^ Would we, 
 therefore, form a just and precise idea of necessity, we 
 must consider whence that idea arises when we apply 
 it to the operation of bodies. 
 
 It seems evident that, if all the scenes of nature 
 were continually shifted in such a manner that no two 
 events bore any resemblance to each other, but every 
 object was entirely new, without any similitude to 
 whatever had been seen before, we should never, in 
 that case, have attained the least idea of necessity, or 
 of a connexion among these objects. We might say, 
 upon such a supposition, that one object or event has 
 followed another ; not that one was produced by the 
 other. \The relation of cause and effect must be utterly 
 unknown to mankind. . Inference and reasoning con- 
 
 , cerning the operations of nature would, from that mo- 
 X.ment, be at an end; and the memory and senses re- 
 
 ^ main the only canals, by which the knowledge of any 
 '*' real existence could possibly have access to the mind. 
 Our idea, therefore, of necessity and causation arises 
 entirely from the uniformity observable in the opera- 
 
HUMAN UNDERSTANDING. 85 
 
 tions of nature, jfwhere siijiilar objects are constantly % 
 conjoined together, and^^he mind is determined by \, 
 custom to infer the one from the appearance of the *^ 
 other. ^ These two circumstances form the whole of 
 that necessity, which we ascribe to matter. • Beyond^ j ** 
 ,fthe constant conjunction of similar objects, and the con- 1 / 
 j sequent inference from one to the other, we have no 3 
 'notion of any necessity or connexion. .-.^..^-^ ----'::::>«*' 
 
 Ttf it appear, therefore, that all manlmiB have ever | 
 allowed, without any doubt or hesitation, that these! J2 
 .,two circumstances take place in the voluntary actionsfY^ 
 / of men, and in the operations of mind ; it must follow,' % 
 1 that all mankind have ever agreed in the doctrine of / 
 j necessity, and that they have hitherto disputed, merel^ 
 
 'for jiot understanding each other. ^.-^--" 
 
 LAs to the first circumstance, the constant and reg- 
 ular conjunction of similar events, we may possibly 
 satisfy ourselves by the following considerations. It 
 is universally acknowledged that there is a great uni- 
 formity among the actions of men, in all nations and 
 ages, and that human nature remains still the same, 
 in its principles and operations. The same motives 
 always produce the same actions :^ The same events 
 follow from the same causes. Ambition, avarice, self- 
 love, vanity, friendship, generosity, public spirit: 
 these passions, mixed in various degrees, and distrib- 
 uted through society, have been, from the beginning 
 of the world, and still are, the source of all the actions 
 and enterprises, which have ever been observed among 
 mankind. Would you know the sentiments, inclina-\ 
 ti.ons, and course of life of the Greeks and Romans ? ( 
 Study well the temper and actions of the French and 
 English : You cannot be much mistaken in transfer- 
 ring to the former most of the observations which you 
 
86 AlSr ENQ UIR V CONCERNING 
 
 have made with regard to the latter. Mankind are so 
 much the same, in all times and places, that history 
 informs us of nothing new or strange in this particular. 
 Its chief use is only to discover the constant and uni- 
 versal principles of human nature, by showing men in 
 all varieties of circumstances and situations, and fur- 
 nishing us with materials from which we may form our 
 observations and become acquainted with the regular 
 springs of human action and behaviour. These rec- 
 ords of wars, intrigues, factions, and revolutions, are 
 so many collections of experiments, by which the poli- 
 tician or moral philosopher fixes the principles of his 
 science, in the same manner as the physician or natu- 
 ral philosopher becomes acquainted with the nature 
 of plants, minerals, and other external objects, by the 
 experiments which he forms concerning them. Nor 
 are the earth, water, and other elements, examined 
 by Aristotle, and Hippocrates, more like to those 
 which at present lie under our observation than the 
 men described by Polybius and Tacitus are to those 
 who now govern the world. 
 
 Should a traveller, returning from a far country, 
 bring us an account of men, wholly different from any 
 with whom we were ever acquainted ; men, who were 
 entirely divested of avarice, ambition, or revenge; 
 who knew no pleasure but friendship, generosity, and 
 public spirit ; we should immediately, from these cir- 
 cumstances, detect the falsehood, and prove him a 
 liar, with the same certainty as if he had stuffed his 
 narration with stories of centaurs and dragons, mira- 
 cles and prodigies. And if we would explode any for- 
 gery in history, we cannot make use of a more convin- 
 cing argument, than to prove, that the actions ascribed 
 to any person are directly contrary to the course of 
 
- HUMAN UNDERSTANDING, 87 
 
 nature, and that no human motives, in such circum- 
 stances, could ever induce him to such a conduct. 
 The veracity of Quintus Curtius is as much to be sus- 
 pected, when he describes the supernatural courage 
 of Alexander, by which he was hurried on singly to 
 attack multitudes, as when he describes his supernat- 
 ural force and activity, by which he was able to resist 
 them. So readily and universally do we acknowledge 
 a uniformity in human motives and actions as well as 
 in the operations of body. 
 
 Hence likewise the benefit of that experience, ac- 
 quired by long life and a variety of business and com- 
 pany, in order to instruct us in the principles of hu- 
 man nature, and regulate our future conduct, as well 
 as speculation. By means of this guide, we mount up 
 to the knowledge of men's inclinations and motives, 
 from their actions, expressions, and even gestures; 
 and again descend to the interpretation of their actions 
 
 Jxova our knowledge of their motives and inclinations. 
 
 I The general observations treasured up by a course of 
 experience, give us the clue of human nature, and 
 teach us to unravel all its intricacies.,/ Pretexts and 
 appearances no longer deceive us. Public declarations 
 pass for the specious colouring of a cause. And though 
 virtue and honour be allowed their proper weight and 
 authority, that perfect disinterestedness, so often pre- 
 tended to, is never expected in multitudes and parties; 
 seldom in their leaders ; and scarcely even in individ- 
 uals of any rank or station. /But were there no uni- 
 formity in human actions, and were every experiment 
 which we could form of this kind irregular and anom- 
 alous, it were impossible to collect any general obser- 
 vations concerning mankind ; and no experience, how- 
 ever accurately digested by reflection, would ever 
 
88 AN ENQ UIR Y CONCERNING 
 
 serve to any purpose. Why is the aged husbandman 
 more skilful in his calling than the young beginner 
 but because there is a certain uniformity in the opera- 
 tion of the sun, rain, and earth towards the production 
 of vegetables \ and experience teaches the old practi- 
 tioner the rules by which this operation is governed 
 and directed./ 
 
 We must not, however, expect that this uniformity 
 of human actions should be carried to such a length 
 as that all men, in the same circumstances, will always 
 act precisely in the same manner, without making any 
 allowance for the diversity of characters, prejudices, 
 and opinions. Such a uniformity in every particular, 
 is found in no part of nature. On the contrary, from 
 observing the variety of conduct in different men, we 
 are enabled to form a greater variety of maxims, which 
 still suppose a degree of uniformity and regularity. 
 
 Are the manners of men different in different ages 
 and countries ? We learn thence the great force of 
 custom and education, which mould the human mind 
 from its infancy and form it into a fixed and established 
 character. Is the behaviour and conduct of the one 
 sex very unlike that of the other ? Is it thence we be- 
 come acquainted with the different characters which 
 nature has impressed upon the sexes, and which she 
 preserves with constancy and regularity? Are the ac- 
 tions of the same person much diversified in the dif- 
 ferent periods of his life, from infancy to old age? 
 This affords room for many general observations con- 
 cerning the gradual change of our sentiments and in- 
 clinations, and the different maxims which prevail in 
 the different ages of human creatures. Even the char- 
 acters, which are peculiar to each individual, have a 
 uniformity in their influence ; otherwise our acquain- 
 
HUMAN UNDERSTANDING, 89 
 
 tance with the persons and our observation of their 
 conduct could never teach us their dispositions, or 
 serve to direct our behaviour with regard to them. 
 
 I grant it possible to find some actions, which seem 
 to have no regular connexion with any known motives, 
 and are exceptions to all the measures of conduct 
 which have ever been established for the government 
 of men. But if we would willingly know what judge- 
 ment should be formed of such irregular and extraor- 
 dinary actions, we may consider the sentiments com- 
 monly entertained with regard to those irregular 
 events which appear in the course of nature, and the 
 operations of external objects. All causes are not con- 
 joined to their usual effects with like uniformity. An 
 artificer, who handles only dead matter, may be dis- 
 appointed of his aim, as well as the politician, who 
 directs the conduct of sensible and intelligent agents. 
 
 The vulgar, who take things according to their first 
 appearance, attribute the uncertainty of events to such 
 an uncertainty in the causes as makes the latter often 
 fail of their usual influence ; though they meet with 
 no impediment in their operation. But philosophers, 
 observing that, almost in every part of nature, there 
 is contained a vast variety of springs and principles, 
 which are hid, by reason of their minuteness or re- 
 moteness; find, that it is at least possible the contra- 
 riety of events may not proceed from any contingency 
 in the cause, but from the secret operation of contrary 
 causes. This possibility is converted into certainty 
 by farther observation, when they remark that, upon 
 an exact scrutiny, a contrariety of effects always be- 
 trays a contrariety of causes, and proceeds from their 
 mutual opposition. A peasant can give no better rea- 
 son for the stopping of any clock or watch than to 
 
90 AN ENQUIEY CONCERNING 
 
 say that it does not commonly go right : But an artist 
 easily perceives that the same force in the spring or 
 pendulum has always the same influence on the wheels; 
 but fails of its usual effect, perhaps by reason of a 
 grain of dust, which puts a stop to the whole move- 
 ment. j|/ From the observation of several parallel in- 
 stances, philosophers form a maxim that the connexion 
 between all causes and effects is equally necessary, 
 i and that its seeming uncertainty in some instances 
 i proceeds from the secret opposition of contrary causes 
 Thus, for instance, in the human body, when'tlie 
 usual symptoms of health or sickness disappoint our 
 expectation ; when medicines operate not with their 
 wonted powers; when irregular events follow from any 
 particular cause ; the philosopher and physician are 
 not surprised at the matter, nor are ever tempted to 
 deny, in general, the necessity and uniformity of those 
 principles by which the animal economy is conducted. 
 They know that a human body is a mighty compli- 
 cated machine : That many secret powers lurk in it, 
 which are altogether beyond our comprehension : That 
 to us it must often appear very uncertain in its opera- 
 tions : And that therefore the irregular events, which 
 outwardly discover themselves, can be no proof that 
 the laws of nature are not observed with the greatest 
 regularity in its internal operations and government. 
 The philosopher, if he be consistent, must apply 
 the same reasoning to the actions and volitions of in- 
 telligent agents. The most irregular and unexpected 
 resolutions of men may frequently be accounted for by 
 those who know every particular circumstance of their 
 character and situation. A person of an obliging dis- 
 position gives a peevish answer : But he has the tooth- 
 ache, or has not dined. A stupid fellow discovers an 
 
HUMAN- UNDERSTANDING. 91 
 
 uncommon alacrity in his carriage : But he has met 
 with a sudden piece of good fortune. Or even when 
 an action, as sometimes happens, cannot be particu- 
 larly accounted for, either by the person himself or by 
 others ; we know, in general, that the characters of 
 men are, to a certain degree, inconstant and irregular. 
 This is, in a manner, the constant character of human 
 nature; though it be applicable, in a more particular 
 manner, to some persons who have no fixed rule for 
 their conduct, but proceed in a continued course of 
 caprice and inconstancy. The internal principles and 
 motives may operate in a uniform manner, notwith- 
 standing these seeming irregularities ; in the same 
 manner as the winds, rain, clouds, and other varia- 
 tions of the weather are supposed to be governed by 
 steady principles ; though not easily discoverable by 
 human sagacity and enquiry. 
 
 j[iThus it appears, not only that the conjunction be- 
 tween jTiaJtiY.es,and voluntary .actioiiLg^is as regular and 
 uniform as that between the cause and effect in any 
 part of nature ; but also that this regular conjunction 
 has been universally acknowledged among mankind, 
 and has never been the subject of dispute, either in 
 philosophy or common life."/ Now, as it is from past 
 experience that we draw all inferences concerning the 
 future, and as we conclude that objects will always be 
 conjoined together which we find to have always been 
 conjoined ; it may seem superfluous to prove that this 
 experienced uniformity in human actions is a source 
 whence we draw inferences concerning them.7 But in 
 order to throw the argument into a greater variety of 
 lights we shall also insist, though briefly, on this 
 latter topic. 
 
 The mutual dependence of men is so great in all 
 
92 AN ENQ UIR Y CONCERNING 
 
 societies that scarce any human action is entirely com- 
 plete in itself, or is performed without some reference 
 to the actions of others, which are requisite to make 
 it answer fully the intention of the agent. The poor- 
 est artificer, who labours alone, expects at least the 
 protection of the magistrate, to ensure him the enjoy- 
 ment of the fruits of his labour. He also expects that, 
 when he carries his goods to market, and offers them 
 at a reasonable price, he shall find purchasers, and 
 shall be able, by the money he acquires, to engage 
 others to supply him with those commodities which 
 are requisite for his subsistence. In proportion as men 
 extend their dealings, and render their intercourse 
 with others more complicated, they always compre- 
 hend, in their schemes of life, a greater variety of vol- 
 untary actions, which they expect, from the proper 
 motives, to co-operate with their own. In all these 
 conclusions they take their measures from past expe- 
 rience, in the same manner as in their reasonings con- 
 cerning external objects ; and firmly believe that men, 
 as well as all the elements, are to continue, in their 
 operations, the same that they have ever found them. 
 A manufacturer reckons upon the labour of his ser- 
 vants for the execution of any work as much as upon 
 the tools which he employs, and would be equally 
 surprised were his expectations disappointed. In 
 short, this experimental inference and reasoning con- 
 cerning the actions of others enters so much into 
 human life, that no man, while awake, is ever a mo- 
 ment without employing it. Have we not reason, 
 therefore, to affirm that all mankind have always 
 agreed in the doctrine of necessity according to the 
 foregoing definition and explication of it ? 
 
 Nor have philosophers ever entertained a different 
 
r 
 
 HUMAN UNDERSTANDING. 93 
 
 Opinion from the people in this particular. For, not 
 to mention that almost every action of their life sup- 
 poses that opinion, there are even few of the specula- 
 tive parts of learning to which it is not essential. What 
 would become of history^ had we not a dependence on 
 the veracity of the historian according to the experi- 
 ence which we have had of mankind ? How could 
 politics be a science, if laws and forms of government 
 had not a uniform influence upon society? Where 
 would be the foundation of moralsy if particular char- 
 acters had no certain or determinate power to produce 
 particular sentiments, and if these sentiments had no 
 constant operation on actions ? And with what pre- 
 tence could we employ our criticism upon any poet or 
 polite author, if we could not pronounce the conduct 
 and sentiments of his actors either natural or unnatu- 
 ral to such characters, and in such circumstances ? _ 
 it seems almost impossible, therefore, to engage eithet" ^^ \ 
 in science or action of any kind without acknowledg- f/1 
 ing the doctrine of necessity, and this inference from /// 
 motive to voluntary actions, from characters to con- /j/ 
 du^tr --"^ 
 
 . And indeed, when we consider how aptly naturat \ 
 and mora/ evidence link together, and form only one ,. 
 chain of argument, we shall make no scruple to allow 
 that they are of the same nature, and derived from the 
 saime principles. A prisoner who has neither money 
 nor interest, discovers the impossibility of his escape, 
 as well when he considers the obstinacy of the goaler, 
 as the walls and bars with which he is surrounded ; 
 and, in all attempts for his freedom, chooses rather to 
 work upon the stone and iron of the one, than upon 
 the inflexible nature of the other. The same prisoner, 
 when conducted to the scaffold, foresees his death as 
 
94 AN ENQ UIR V CONCERNING 
 
 certainly from the constancy and fidelity of his guards, 
 as from the operation of the axe or wheel. His mind 
 runs along a certain train of ideas ; The refusal of the 
 soldiers to consent to his escape ; the action of the 
 executioner ; the separation of the head and body ; 
 bleeding, convulsive motions, and death. Here is a 
 connected chain of natural causes and voluntary ac- 
 tions ; but the mind feels no difference between them 
 in passing from one link to another : Nor is less cer- 
 tain of the future event than if it were connected with 
 the objects present to the memory or senses, by a train 
 of causes, cemented together by what we are pleased 
 to call a physical necessity. The same experienced 
 union has the same effect on the mind, whether the 
 united objects be motives, volition, and actions ; or 
 figure and motion. We may change the name of 
 things ; but their nature and their operation on the 
 understanding never change. 
 
 Were a man, whom I know to be honest and opu- 
 lent, and with whom I live in intimate friendship, to 
 come into my house, where I am surrounded with my 
 servants, I rest assured that he is not to stab me be- 
 fore he leaves it in order to rob me of my silver stand- 
 ish ; and I no more suspect this event than the fall- 
 ing of the house itself, which is new, and solidly built 
 and founded. — But he may have been seized with a sud- 
 den and unknown frenzy. — So may a sudden earthquake 
 arise, and shake and tumble my house about my ears- 
 I shall therefore change the suppositions. I shall say 
 that I know with certainty that he is not to put his 
 hand into the fire and hold it there till it be consumed : 
 And this event, I think I can foretell with the same 
 assurance, as that, if he throw himself out at the win- 
 dow, and meet with no obstruction, he will not remain 
 
HUMAN UNDERSTANDING, 95 
 
 a moment suspended in the air. No suspicion of an 
 unknown frenzy can give the least possibility to the 
 former event, which is so contrary to all the known 
 principles of human nature. A man who at noon 
 leaves his purse full of gold on the pavement at Char- 
 ing-Cross, may as well expect that it will fly away like 
 a feather, as that he will find it untouched an hour 
 after. /Above one half of human reasonings contain 
 inferences of a similar nature, attend ed w ith more or 
 less degrees of certainty proportioned to our experP" 
 ence of the usual conduct of mankind in such partic- 
 ular situations.! ""^ 
 I have fre5«ently considered, what could possibly 
 be the reason why all mankind, though they have 
 ever, without hesitation, acknowledged the doctrine 
 of necessity in their whole practice and reasoning, 
 have yet not discovered such a reluctance to acknowl- 
 edge it in words, and have rather shown a propensity, 
 in all ages, to profess the contrary opinion. The mat- 
 ter, I think, may be accounted for after the following 
 manner. If we examine the operations of body, and 
 the production of effects from their causes, we shall 
 find that all our faculties can never carry us farther in 
 our knowledge of this relation than barely to observe 
 that particular objects are constantly conjoined together, 
 and that the mind is carried, by a customary transition^ 
 from the appearance of one to the belief of the other. 
 But though this conclusion concerning human ignor- 
 ance be the result of the strictest scrutiny of this sub- 
 ject, men still entertain a strong propensity to believe 
 that they penetrate farther into the powers of nature, 
 and perceive something like a necessary connexion 
 between the cause and the effect. When again they 
 turn their reflections towards the operations of their 
 
96 AN ENQUIR Y CONCERNING 
 
 own minds, and pd no such connexion of the motive 
 ll and the action;; they are thence apt to suppose, that 
 I- there is a difference between the effects which result 
 ; from material force, and those which arise from 
 If thought and intelligence. iBut being once convinced 
 / that we know nothing farther of causation of any kind 
 / than merely the constant conjunction of objects, and the 
 I consequent inference of the mind from one to another, 
 and finding that these two circumstances are univer- 
 sally allowed to have place in voluntary actions ; we 
 may be more easily 1^ to own the same necessity 
 common to all causes^ And though this reasoning 
 may contradict the systems of many philosophers, in 
 ascribing necessity to the determinations of the will, 
 we shall find, upon reflection, that they dissent from 
 it in words only, not in their real sentiment. Neces- 
 sity, according to the sense in which it is here taken, 
 has never yet been rejected, nor can ever, I think, be 
 rejected by any philosopher. It may only, perhaps, 
 be pretended that the mind can perceive, in the opera- 
 tions of matter, some farther connexion between the 
 cause and effect ; and connexion that has not place in 
 voluntary actions of intelligent beings. Now whether 
 it be so or not, can only appear upon examination ; 
 ,^nd it is incumbent on these philosophers to make 
 good their assertion, by defining or describing that 
 necessity, and pointing it out to us in the operations 
 of material causes. 
 
 It would seem^indeed, that men begin at the wrong 
 end of this question concerning liberty and necessity, 
 when they enter upon it by examining the faculties of 
 the soul, the influence of the understanding, and the 
 operations of the will. iXet them first discuss a more 
 simple question, namely, the operations of body and 
 
HUMAN UNDERSTANDING, 97 
 
 of brute unintelligent matter ; and try whether theyj 
 can there form any idea of causation and necessity, 
 except that of a constant conjunction of objects, and 
 subsequent inference of the mind from one to another. 
 If these circumstances form, in reality, the whole of 
 that necessity, which we conceive in matter, and if 
 these circumstances be also universally acknowledged 
 to take place in the operations of the mind, the dis- 
 pute is at an end ; at least, must be owned to be 
 thenceforth merely verbal. But as long as we will 
 rashly suppose, that we have some farther idea of 
 necessity and causation in the operations of external 
 objects ; at the same time, that we can find nothing 
 farther in the voluntary actions of the mind ; there is 
 no possibility of bringing the question to any deter- 
 minate issue, while we proceed upon so erroneous a 
 supposition. The only method of undeceiving us is 
 to mount up higher ; to examine the narrow extent of 
 science when applied to material causes ; and to con- 
 vince ourselves that all we know of them is the con- 
 stant conjunction and inference above mentioned. We 
 may, perhaps, find that it is with difficulty we are in- 
 duced to fix such narrow limits to human understand- 
 ing : But we can afterwards find no difficulty when 
 we come to apply this doctrine to the actions of the 
 will. For as it is evident that these have a regular 
 conjunction with motives and circumstances and char- 
 acters, and as we always draw inferences from one to, 
 the other, we must be obliged to acknowledge in words 
 that necessity, which we have already avowed, in 
 every deliberation of our lives, and in every step of 
 our conduct and behaviour.^ 
 
 1 The prevalence of the doctrine of liberty may be accounted for, from 
 another cause, viz. a false sensation or seeming experience which we have, 
 
98 AN ENQUIRY CONCERmNG 
 
 But to proceed in this reconciling project with re- 
 gard to the question of liberty and necessity ; the most 
 contentious question of metaphysics, the most con- 
 tentious science ; it will not require many words to 
 prove, that all mankind have ever agreed in the doc- 
 trine of liberty as well as in that of necessity, and that 
 the whole dispute, in this respect also, has been hith- 
 erto merely verbal. For what is meant by liberty, 
 when applied to voluntary actions ? We cannot surely 
 mean that actions have so little connexion with mo- 
 tives, inclinations, and circumstances, that one does 
 not follow with a certain degree of uniformity from the 
 other, and that one affords no inference by which we 
 can conclude the existence of the other. For these are 
 
 or may have, of liberty or indifiference, in many of our actions. The necessity 
 of any action, whether of matter or of mind, is not, properly speaking, a qual- 
 ity in the agent, but in any thinking or intelligent being, who may consider 
 the action ; and it consists chiefly in the determination of his thoughts to 
 infer the existence of that action from some preceding objects; as liberty, 
 when opposed to necessity, is nothing but the want of that determination, 
 and a certain looseness or indifference, which we feel, in passing, or not 
 passing, from the idea of one object to that of any succeeding one. Now we 
 may observe, that, though, in reflecting on human actions, we seldom feel 
 such a looseness, or indifference, but are commonly able to infer them with 
 considerable certainty from their motives, and from the dispositions of the 
 agent; yet it frequently happens, that, in /^^^w/«^ the actions themselves, 
 we are sensible of something like it; And as all resembling objects are readily 
 taken for each other, this has been employed as a demonstrative and even 
 intuitive proof of human liberty. We feel, that our actions are subject to our 
 will, on most occasions; and imagine we feel, that the will itself is subject 
 to nothing, because, when by a denial of it we are provoked to try, we feeli 
 that it moves easily every way, and produces an image of itself (or a Vellelty' 
 as it is called in the schools) even on that side, on which it did net settle. 
 This image, or faint motion, we persuade ourselves, could, at that time, have 
 been compleated into the thing itself; because, should that be denied, we 
 find, upon a second trial, that, at present, it can. We consider not, that the 
 fantastical desire of jewing liberty, is here the motive of our actions. And 
 it seems certain, thatJhowever we may imagine we feel a liberty within our- 
 selves, a spectator can commonly infer our actions from our motives and 
 character;, 'and even where he cannot, he concludes in general, that he might, 
 were he perfectly acquainted with every circumstance of our situation and 
 temper, and the most secret springs of our complexion and disposition. Now 
 this is the very essence of necessity, according to the foregoing doctrine. 
 
HUMAN UNDERSTANDING. 99 
 
 plain and acknowledged matters of fact. '^By libert)^ V 
 then, we can only mean a power of actingor not actingi 
 
 according to the determinations of the wi/jhfjth.3it is, if we 
 
 choose to remain at rest, we may; if we~cEoosB^to 
 ni6ve,"we "al:Ba"may:~~"Nowl:^^ HypbTfietical liberty is 
 universally allowed to belong to every one who is not 
 a prisoner and in chains. Here, then, is no subject 
 of dispute. 
 
 Whatever definition we may give of liberty, we 
 should be careful to observe two requisite circum- 
 stances ; frst, that it be consistent with plain matter 
 of fact ; secondly y that it be consistent with itself. If 
 we observe these circumstances, and render our defi- 
 nition intelligible, I am persuaded that all mankind 
 will be found of one opinion with regard to it. 
 
 |~It is universally allowed that nothing exists with- ^^'^ '. 
 out a cause of its existence, and that chance, wher d^^^'T 
 strictly examined, is a mere negative word, and means 
 not any real power which has anywhere a being in\ 
 nature. ] But it is pretended that some causes are ne- 
 cessary, some not necessary. Here then is the ad- 
 vantage of definitions. Let any one define a cause, 
 without comprehending, as a part of the definition, a 
 necessary connexion with its effect ; and let him show 
 distinctly the origin of the idea, expressed by the defi- 
 nition ; and I shall readily give up the whole contro- 
 versy. But if the foregoing explication of the matter 
 be received, this must be absolutely impracticable. 
 Had not objects a regular conjunction with each other, 
 we should never have entertained any notion of cause 
 and effect ; and thia_regular conjunction produces that 
 inference of the understanding, which is the only con 
 nexion, that we can have any comprehension of. 
 Whoever attempts a definition of cause, exclusive of ' 
 
 tj Ja^ 
 
loo AN ENQUIRY CONCERNING 
 
 these circumstances, will be obliged either to employ 
 unintelligible terms or such as are synonymous to 
 the term which he endeavours to define. ^ And if the 
 definition above mentioned be admitted ; liberty, when 
 opposed to necessity, not to constxaint, is the same 
 thing with chance; which is universally allowed to 
 have no existence^ 
 
 y^ Part II. 
 
 / There is no method of reasoning more common, 
 and yet none more blameable, than, in philosophical 
 disputes, to endeavour the refutation of any hypothe- 
 sis, by a pretence of its dangerous consequences to 
 religion and morality. | When any opinion leads to 
 absurdities, it is certainly false ; but it is not certain 
 that an opinion is false, because it is of dangerous 
 consequence. Such topics, therefore, ought entirely 
 to be forborne ; as serving nothing to the discov- 
 ery of truth, but only to make the person of an antag- 
 onist odious. This I observe in general, without 
 pretending to draw any advantage from it. I frankly" 
 submit to an examination of this kind, and shall ven- 
 ture to affirm that the doctrines, both of necessity and 
 of liberty, as above explained, are not only consistent 
 with morality, but are absolutely essential to its 
 support. ' ^ 
 
 Necessity may be defined two ways, conformably 
 
 1 Thus, if a cause be defined, that which produces any thing; it is easy to 
 observe, that producing is synonimous to causing. In like manner, if a cause 
 be defined, that by which any thing exists; this is liable to the same objec- 
 tion. For what is meant by these words, by which ? Had it been said, that a 
 cause is that after which any thing constantly exists; we should have under- 
 stood the terms. For this is, indeed, all we know of the matter. And this 
 constancy forms the very essence of necessity, nor have we any other idea 
 of it. 
 
HUMAN UNDERSTANDING. loi . 
 
 to the two definitjpns of cause, of which it makes an . -| V^ 
 essential part. [j[t_c^on^ists_ejther_ jnjthe_^ ^0^ 
 
 conjunction of like objects, or in the inference of the^ 
 understanding from one object to another. Now ne- 
 cessity, in both these senses, (which, indeed, are at 
 bottom the same) has universally, though tacitly, in 
 the schools, in the pulpit, and in common life, been 
 allowed to belong to the will of man ; and no one has 
 ever pretended to deny that we can draw inferences 
 concerning human actions, and that those inferences « 
 are founded on the experienced union of like actions, 
 with like motives, inclinations, and circumstances. 
 The only particular in which any one can differ, is, 
 that either, perhaps, he will refuse to give the name 
 of necessity to this property of human actions: But 
 as long as the meaning is understood, I hope the word 
 can do no harm : Or that he will maintain it possible 
 to discover something farther in the operations of 
 matter. But this, it must be acknowledged, can be 
 of no consequence to morality or religion, whatever it 
 may be to natural philosophy or metaphysics. We 
 may here be mistaken in asserting that there is no idea 
 of any other necessity or connexion in the actions of 
 body : But surely we ascribe nothing to the actions 
 of the mind, but what everyone does, and must readily 
 allow of. We change no circumstance in the received 
 orthodox system with regard to the will, but only in 
 that with regard to material objects and causes. Noth- 
 ing, therefore, can be more innocent, at least, than 
 this doctrine. 
 
 All laws being founded on rewards and punish- 
 ments, it is supposed as a fundamental principle, that 
 these motives have a regular and uniform influence on 
 the mind, and both produce the good and prevent the 
 
io2 AN ENQUIRY CONCERNING 
 
 evil actions. We may give to this influence what 
 name we please \ but, as it is usually conjoined with 
 the action, it must be esteemed a cause, and be looked 
 upon as an instance of that necessity, which we would 
 here establish. 
 
 The only proper object of hatred or vengeance is 
 a person or creature, endowed with thought and con- 
 sciousness ; and when any criminal or injurious ac- 
 tions excite that passion, it is only by their relation to 
 the person, or connexion with him. /'Actions are, by 
 their very nature, temporary and perishing ; and 
 where they proceed not from some cause in the char- 
 acter and disposition of the person who performed 
 them, they can neither redound to his honour, if good; 
 nor infamy, if evil. The actions themselves may be 
 blameable; they may be contrary to all the rules of 
 morality and religion : But the person is not answer- 
 able for them ; and as they proceeded from nothing in 
 him that is durable and constant, and leave nothing 
 of that nature behind them, it is impossible he can, 
 upon their account, become the object of punishment 
 ^ or vengeance. According to the principle, therefore, 
 which denies necessity, and consequently causes, a 
 man is as pure and untainted, after having committed 
 the most horrid crime, as at the first moment of his 
 birth, nor is his character anywise concerned in his 
 actions, since they are not derived from it, and the 
 wickedness of the one can never be used as a proof of 
 the depravity of the other. 
 
 Men are not blamed for such actions as they per- 
 form ignorantly and casually, whatever may be the 
 consequences. Why ? but because the principles of 
 these actions are only momentary, and terminate in 
 them alone. Men are less blamed for such actions as 
 
HUMAN- UNDERSTANDING. 103 
 
 they perform hastily and unpremeditately than for such 
 as proceed from deliberation. For what reason ? but 
 because a hast}' temper, though a constant cause or 
 principle in the mind, operates only by intervals, and 
 infects not the whole character. Again, repentance 
 wipes off every crime, if attended with a reformation 
 of life and manners. How is this to be accounted for? 
 but by asserting that actions render a person criminal 
 merely as they are proofs of criminal principles in the 
 mind; and when, by an alteration of these principles, 
 they cease to be just proofs, they likewise cease to be 
 iriminal. But, except upon the doctrine of necessity, 
 they never were just proofs, and consequently never 
 were criminal. 
 
 It will be equally easy to prove, and from the same 
 arguments, that liberty^ according to that definition 
 above mentioned, in which all men agree, is also es- 
 sential to morality, and that no human actions, where 
 it is wanting, are susceptible of any moral qualities, 
 or can be the objects either of approbation or dislike. 
 For as actions are objects of our moral sentiment, so 
 far only as they are indications of the internal char- 
 acter, passions, and affections ; it is impossible that 
 they can give rise either to praise or blame, where 
 they proceed not from these principles, but are derived 
 altogether frem external violence. 
 
 I pretend not to have obviated or removed all ob- 
 jections to. this theory, with regard to necessity and 
 liberty. I can foresee other objections, derived from 
 topics which have not here been treated of. It may 
 be said, for instance, that, if voluntary actions be sub- 
 jected to the same laws of necessity with the operations 
 of matter, there is a continued chain of necessary 
 causes, pre-ordained and pre-determined, reaching 
 
I04 AN ENQUIRY CONCERNING 
 
 from the original cause of all to every single volition 
 of every human creature. No contingency anywhere 
 in the universe \ no indifference ; no liberty. While 
 we act, we are, at the same time, acted upon. The 
 ultimate Author of all our volitions is the Creator of 
 the world, who first bestowed motion on this immense 
 machine, and placed all beings in that particular 
 position, whence every subsequent event, by an in- 
 evitable necessity, must result. Human actions, 
 therefore, either can have no moral turpitude at all, as 
 proceeding from so good a cause ; or if they have any 
 turpitude, they must involve our Creator in the same 
 guilt, while he is acknowledged to be their ultimate 
 cause and author. For as a man, who fired a mine, 
 is answerable for all the consequences whether the 
 train he employed be long or short ; so wherever a 
 continued chain of necessary causes is fixed, that Be- 
 ing, either finite or infinite, who produces the first, is 
 likewise the author of all the rest, and must both bear 
 the blame and acquire the praise which belong to them. 
 Our clear and unalterable ideas of morality establish 
 this rule, upon unquestionable reasons, when we ex- 
 amine the consequences of any human action ; and 
 these reasons must still have greater force when ap- 
 plied to the volitions and intentions of a Being infi- 
 nitely wise and powerful. Ignorance or impotence 
 may be pleaded for so limited a creature as man ; but 
 those imperfections have no place in our Creator. He 
 foresaw, he ordained, he intended all those actions of 
 men, which we so rashly pronounce criminal. And we 
 must therefore conclude, either that they are not crim- 
 inal, or that the Deity, not man, is accountable for 
 them. But as either of these positions is absurd and 
 impious, it follows, that the doctrine from which they 
 
HUMAN UNDERSTANDING, 105 
 
 are deduced cannot possibly be true, as being liable 
 to all the same objections. An absurd consequence, 
 if necessary, proves the original doctrine to be absurd ; 
 in the same manner as criminal actions render crim- 
 inal the original cause, if the connexion between them 
 be necessary and evitable. 
 
 This objection consists of two parts, which we shall 
 examine separately ; First, that, if human actions can 
 be traced up, by a necessary chain, to the Deity, they 
 can never be criminal \ on account of the infinite per- 
 fection of that Being from whom they are derived, 
 and who can intend nothing but what is altogether 
 good and laudable. Or, Secondly, if they be criminal, 
 we must retract the attribute of perfection, which we 
 ascribe to the Deity, and must acknowledge him to 
 be the ultimate author of guilt and moral turpitude in 
 all his creatures. 
 
 The answer to the first objection seems obvious 
 and convincing. There are many philosophers who, 
 after an exact scrutiny of all the phenomena of nature, 
 conclude, that the whole, considered as one system, 
 is, in every period of its existence, ordered with per- 
 fect benevolence; and that the utmost possible happi- 
 ness will, in the end, result to all created beings, with- 
 out any mixture of positive or absolute ill or misery. 
 Every physical ill, say they, makes an essential part 
 of this benevolent system, and could not possibly be 
 removed, even by the Deity himself, considered as a 
 wise agent, without giving entrance to greater ill, or 
 excluding greater good, which will result from it. 
 From this theory, some philosophers, and the ancient 
 Stoics among the rest, derived a topic of consolation 
 under all afflictions, while they taught their pupils 
 that those ills under which they laboured were, in real- 
 
io6 AN ENQ UIR V CONCERNING 
 
 ity, goods to the universe; and that to an enlarged 
 view, which could comprehend the whole system of 
 nature, every event became an object of joy and exul- 
 tation. But though this topic be specious and sub- 
 lime, it was soon found in practice weak and ineffec- 
 tual. You would surely more irritate than appease a 
 man lying under the racking pains of the gout by 
 preaching up to him the rectitude of those general 
 laws, which produced the malignant humours in his 
 body, and led them through the proper canals, to the 
 sinews and nerves, where they now excite such acute 
 torments. These enlarged views may, for a moment, 
 please the imagination of a speculative man, who is 
 placed in ease and security; but neither can they dwell 
 with constancy on his mind, even though undisturbed 
 by the emotions of pain or passion; much less can 
 they maintain their ground when attacked by such 
 powerful antagonists. The affections take a narrower 
 and more natural survey of their object ; and by an 
 economy, more suitable to the infirmity of human 
 minds, regard alone the beings around us, and are 
 actuated by such events as appear good or ill to the 
 private system. 
 
 The case is the same with moral as with physical ill. 
 It cannot reasonably be supposed, that those remote 
 considerations, which are found of so little efficacy 
 with regard to one, will have a more powerful influ- 
 ence with regard to the other. The mind of man is 
 so formed by nature that, upon the appearance of cer- 
 tain characters, dispositions, and actions, it immedi- 
 ately feels the sentiment of approbation or blame; nor 
 are there any emotions more essential to its frame and 
 constitution. jThe characters which engage our ap- 
 probation are cHiefly such as contribute to the peace 
 
HUMAN UNDERSTANDING. 107 
 
 and security of human society; as the characters which 
 excite blame are chiefly such as tend to public detri- 
 ment and disturbance ^Whence it may reasonably be 
 presumed, that the rfioral sentiments arise, either me- 
 diately or immediately, from a reflection of these op- 
 posite interests. What though philosophical medita- 
 tions establish a different opinion or conjecture ; that 
 everything is right with regard to the whole, and that 
 the qualities, which disturb society, are, in the main, 
 as beneficial, and are as suitable to the primary in- 
 tention of nature as those which more directly pro- 
 mote its happiness and welfare? Are such remote and 
 uncertain speculations able to counterbalance the sen- 
 timents which arise from the natural and immediate 
 view of the objects? A man who is robbed of a con- 
 siderable sum ; does he find his vexation for the loss 
 anywise diminished by these sublime reflections? Why 
 then should his moral resentment against the crime 
 be supposed incompatible with them? Or why should 
 not the acknowledgment of a real distinction between 
 vice and virtue be reconcileable to all speculative sys- 
 tems of philosophy, as well as that of a real distinction 
 between personal beauty and deformity? Both these 
 distinctions are founded in the natural sentiments of 
 the human mind: And these sentiments are not to 
 be controuled or altered by any philosophical theory 
 or speculation whatsoever. 
 
 The second objection admits not of so easy and sat- 
 isfactory an answer ; nor is it possible to explain dis- 
 tinctly, how the Deity can be the mediate cause of all 
 the actions of men, without being the author of sin 
 and moral turpitude. These are mysteries, which mere 
 natural and unassisted reason is very unfit to handle ; 
 and whatever system she embraces, she must find her- 
 
zo8 
 
 self involved in inextricable difficulties, and even con- 
 tradictions, at every step which she takes with regard 
 to such subjects. To reconcile the indifference and 
 contingency of human actions with prescience; or to 
 defend absolute decrees, and yet free the Deity from 
 being the author of sin, has been found hitherto to ex- 
 ceed all the power of philosophy. Happy, if she be 
 thence sensible of her temerity, when she pries into 
 these sublime mysteries ; and leaving a scene so full 
 of obscurities and perplexities, return, with suitable 
 modesty, to her true and proper province, the exami- 
 nation of common life; where she will find difficulties 
 enough to employ her enquiries, without launching 
 into so boundless an ocean of doubt, uncertainty, and 
 contradiction ! 
 
 N. 
 
SECTION IX. 
 
 OF THE REASON OF ANIMALS 
 
 / /\LL our reasonings concerning matter of fact are 
 jTJl. founded on a species of Analogy which leads us 
 to expect from any cause the same events, which we 
 have observed to result from similar causes, j Where 
 the causes are entirely similar, the analogyls perfect, 
 and the inference, drawn from it, is regarded as cer- 
 tain and conclusive: nor does any man ever entertain 
 a doubt, when he sees a piece of iron, that it will have 
 weight and cohesion of parts; as in all other instances, 
 which have ever fallen under his observation. But 
 where the objects have not so exact a similarity, the 
 analogy is less perfect, and the inference is less con- 
 clusive ; though still it has some force, in proportion 
 to the degree of similarity and resemblance. The ana- 
 tomical observations, formed upon one animal, are, 
 by this species of reasoning, extended to all animals; 
 and it is certain, that when the circulation of the blood, 
 for instance, is clearly proved to have place in one 
 creature, as a frog, or fish, it forms a strong presump- 
 tion, that the same principle has place in all. These 
 analogical observations may be carried farther, even 
 to this science, of which we are now treating; and 
 any theory, by which we explain the operations of the 
 understanding, or the origin and connexion of the 
 passions in man, will acquire additional authority, if 
 we find, that the same theory is requisite to explain 
 
no AN ENQUIRY CONCERNING 
 
 the same phenomena In all other animals. We shall 
 make trial of this, with regard to the hypothesis, by 
 which we have, in the foregoing discourse, endeav- 
 oured to account for all experimental reasonings; and 
 it is hoped, that this new point of view will serve to 
 confirm all our former observations. 
 
 First, It seems evident, that animals as well as men 
 learnltnany things from experience, and infer, that the 
 same events will always follow from the same causes. 
 By this principle they become acquainted with the 
 more obvious properties of external objects, and grad- 
 ually, from their birth, treasure up a knowledge of the 
 nature of fire, water, earth, stones, heights, depths, 
 &c., and of the effects which result from their opera- 
 tion. The ignorance and inexperience of the young 
 are here plainly distinguishable from the cunning and 
 sagacity of the old, who have learned, by long obser- 
 vation, to avoid what hurt them, and to pursue what 
 gave ease or pleasure. A horse, that has been accus- 
 tomed to the field, becomes acquainted with the proper 
 height which he can leap, and will never attempt what 
 exceeds his force and ability. An old greyhound will 
 trust the more fatiguing part of the chace to the 
 younger, and will place himself so as to meet the hare 
 in her doubles; nor are the conjectures, which he 
 forms on this occasion, founded in any thing but his 
 observation and experience. 
 
 This is still more evident from the effects of disci- 
 pline and education on animals, who, by the proper 
 application of rewards and punishments, may be taught 
 any course of action, and most contrary to their natu- 
 ral instincts and propensities. Is it not experience, 
 which renders a dog apprehensive of pain, when you 
 menace him, or lift up the whip to beat him ? Is it 
 
HUMAN UNDERSTANDING, iii 
 
 not even experience, which makes him answer to his 
 name, and infer, from such an arbitrary sound, that 
 you mean him rather than any of his fellows, and in- 
 tend to call him, when you pronounce it in a certain 
 manner, and with a certain tone and accent? 
 
 J' In all these cases, we may observe, that the animal 
 fers some fact beyond what immediately strikes his 
 senses ; and that this inference is altogether founded 
 on past experience, while the creature expects from 
 the present object the same consequences, which it has 
 always found in its observation to result from similar 
 objects. \ ^"^ 
 
 Secondly, It is impossible, that this inference of the 
 animal can be founded on any process of argument or 
 reasoning, by which he concludes, that like events 
 must follow like objects, and that the course of nature 
 will always be regular in its operations. For if there 
 be in reality any arguments of this nature, they surely 
 lie too abstruse for the observation of such imperfect 
 understandings ; since it may well employ the utmost 
 care and attention of a philosophic genius to discover 
 and observe them./ Animals, therefore, are not guided 
 in these inferences by reasoning : Neither are chil- 
 dren : Neither are the generality of mankind, in their 
 ordinary actions and conclusions : Neither are philos- 
 ophers themselves, who, in all the active parts of life, 
 are^iri_the main, the same with the vulgar, and are , 
 governed by the same maxims. Nature must have^ 
 provided some other principle, ""of more ready, and I 
 more general use and application;! nor can an opera- \ 
 tion of such immense consequence in life, as that of \ 
 inferring effects from causes, be trusted to the uncer- ] 
 tain process of reasoning and argumentation. \ Were 
 this doubtful with regard to men, it seems to'admit oi 
 
II 
 
 IZ2 AN ENQUIRY CONCERNING 
 
 no question with regard to the brute creation ; and 
 the conclusion being once firmly established in the 
 one, we have a strong presumption, from all the rules 
 of analogy, that it ought to be universally admitted, 
 without any exception or reserve, ^t is custom aloneJ 
 which engages animals, from every o^ject^tTiat'strikes 
 their senses, to infer its usual attendant, and carries 
 their imagination, from the appearance of the one, to 
 conceive the other, in that particular manner, which 
 we denominate belief. No other explication can be 
 given of this op^ation, in all the higher, as well as 
 lower classes of sensitive beings, which fall under our 
 notice and observation.^ 
 
 1 Since all reasonings concerning facts or causes is derived merely from 
 custom, it may be asked how it happens, that men so much surpass animals 
 in reasoning, and one man so much surpasses another? Has not the same 
 custom the same influence on all? 
 
 We shall here endeavour briefly to explain the great difiference in human 
 understandings: After which the reason of the difference between men and 
 animals will easily be comprehended. 
 
 1. When we have lived any time, and have been accustomed to the uni- 
 formity of nature, we acquire a general habit, by which we always transfer 
 the known to the unknown, and conceive the latter to resemble the former. 
 By means of this general habitual principle, we regard even one experiment 
 as the foundation of reasoning, and expect a similar event with some degree 
 of certainty, where the experiment has been made accurately, and free from 
 all foreign circumstances. It is therefore considered as a matter of great 
 importance to observe the consequences of things; and as one man may very 
 much surpass another in attention and memory and observation, this will 
 make a very great difiference in their reasoning. 
 
 2. Where there is a complication of causes to produce any effect, one 
 mind may be much larger than another, and better able to comprehend the 
 whole system of objects, and to infer justly their consequences. 
 
 3. One man is able to carry on a chain of consequences to a greater 
 length than another. 
 
 4. Few men can think long without running into a confusion of ideas, 
 and mistaking one for another; and there are various degrees of this in- 
 firmity. 
 
 5. The circumstance, on which the effect depends, is frequently involved 
 in other circumstances, which are foreign and extrinsic. The separation of 
 it often requires great attention, accuracy, and subtilty. 
 
 6. The forming of general maxims from particular observation is a very 
 nice operation ; and nothing is more usual, from haste or narrowness of mind 
 which sees not on all sides, than to commit mistakes in this particular. 
 
HUMAN UNDERSTANDING. 113 
 
 But though animals learn many parts of their 
 knowledge from observation, there are also many parts 
 of it, which they derive from the original hand of nature; 
 which much exceed the share of capacity they possess 
 on ordinary occasions ; and in which they improve, 
 little or nothing, by the longest practice and experi- 
 ence. These we denominate Instincts, and are so apt 
 to admire as something very extraordinary, and inexpli- 
 cable by all the disquisitions 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 op- 
 erations, is not directed by any such relations or com- 
 parisons of ideas, as are the proper objects of our in- 
 tellectual faculties. Though the instinct be different, 
 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. 
 
 7. When we reason from analogies, the man, who has the greater expe- 
 rience or the greater promptitude of suggesting analogies, will be the better 
 reasoner. 
 
 8. Byasses from prejudice, education, passion, party, &c., hang more 
 upon one mind than another. 
 
 9. After we have acquired a confidence in human testimony, books and 
 conversation enlarge much more the sphere of one man's experience and 
 thought than those of another. 
 
 It would be easy to discover many other circumstances that make a dif* 
 ference in the understandings of men. 
 
SECTION X 
 
 OF MIRACLES. 
 Part I. 
 
 THERE is, in Dr. Tillotson's writings, an argument 
 against the real presence, which is as concise, and 
 elegant, and strong as any argument can possibly be 
 supposed against a doctrine, so little worthy of a seri- 
 ous refutation. It is acknowledged on all hands, says 
 that learned prelate, that the authority, either of the 
 scripture or of tradition, is founded merely in the tes- 
 timony of the apostles, who were eye-witnesses to 
 those miracles of our Saviour, by which he proved his 
 divine mission. Our evidence, then, for the truth of 
 the Christian religion is less than the evidence for the 
 truth of our senses ; because, even in the first authors 
 of our religion, it was no greater ; and it is evident it 
 must diminish in passing from them to their disciples; 
 nor can any one rest such confidence in their testi- 
 mony, as in the immediate object of his senses. But 
 a weaker evidence can never destroy a stronger; and 
 therefore, were the doctrine of the real presence ever 
 so clearly revealed in scripture, it were directly con- 
 trary to the rules of just reasoning to give our assent 
 to it. It contradicts sense, though both the scripture 
 and tradition, on which it is supposed to be built, 
 carry not such evidence with them as sense; when they 
 are considered merely as external evidences, and are 
 
HUMAN UNDERSTANDING. 115 
 
 not brought home to every one's breast, by the imme- 
 diate operation of the Holy Spirit. 
 
 Nothing is so convenient as a decisive argument of 
 this kind, which must at least silence the most arrogant 
 bigotry and superstition, and free us from their imper- 
 tinent solicitations. I flatter myself, that I have dis- 
 covered an argument of a like nature, which, if just, 
 will, with the wise and learned, be an everlasting check 
 to all kinds of superstitious delusion, and conse- 
 quently, will be useful as long as the world endures. 
 For so long, I presume, will the accounts of miracles 
 and prodigies be found in all history, sacred and pro- 
 fane. 
 
 / Though experience be our only guide in reasoning 
 concerning matters of fact ; it must be acknowledged, 
 that this guide is not altogether infallible, but in some^ 
 cases is apt to lead us into errors. One, who in our 
 climate, should expect better weather in any week of 
 June than in one of December, would reason justly, 
 and conformably to experience ; but it is certain, that 
 he may happen, in the event, to find himself mistaken. 
 However, we may observe, that, in such a case, he 
 would have no cause to complain of experience ; be- 
 cause it commonly informs us beforehand of the un- 
 certainty, by that contrariety of events, which we may 
 learn from a diligent observation. All effects follow 
 not with like certainty from their supposed causes. 
 Some events are found, in all countries and all ages, 
 to have been constantly conjoined together : Others 
 are found to have been more variable, and sometimes 
 to disappoint our expectations; so that, in our reason- 
 ings concerning matter of fact, there are all imaginable 
 degrees of assurance, from the highest certainty to the 
 lowest species of moral evidence. 
 
1 16 AN ENQ UIR V CONCERNING 
 
 A wise man, therefore, proportions his belief to the 
 evidence. In such conclusions as are founded on an 
 infallible experience, he expects the event with the last 
 degree of assurance, and regards his past experience 
 as a full proof of the future existence of that event. 
 In other cases, he proceeds with more caution : He 
 weighs the opposite experiments : He considers 
 which side is supported by the greater number of ex- 
 periments : to that side he inclines, with doubt and 
 hesitation; and when at last he fixes his judgement, 
 the evidence exceeds not what we properly call prob- 
 ability. All probability, then, supposes an opposition 
 of experiments and observations, where the one side 
 is found to overbalance the other, and to produce a 
 degree of evidence, proportioned to the superiority. 
 A hundred instances or experiments on one side, and 
 fifty on another, afford a doubtful expectation of any 
 event ; though a hundred uniform experiments, with 
 only one that is contradictory, reasonably begets a 
 pretty strong degree of assurance. In all cases, we 
 must balance the opposite experiments, where they 
 are opposite, and deduct the smaller number from the 
 greater, in order to know the exact force of the supe- 
 rior evidence. 
 
 To apply these principles to a particular instance ; 
 we may observe, that there is no species of reasoning 
 more common, more useful, and even necessary to 
 human life, than that which is derived from the testi- 
 mony of men, and the reports of eye-witnesses and 
 spectators. This species of reasoning, perhaps, one 
 may deny to be founded on the relation of cause and 
 effect. I shall not dispute about a word. It will be 
 sufficient to observe that our assurance in any argu- 
 ment of this kind is derived from no other principle 
 
HUMAN UNDERSTANDING, 117 
 
 than our observation of the veracity of human testi- 
 mony, and of the usual conformity of facts to the re- 
 ports of witnesses. It being a general maxim, that 
 no objects have any discoverable connexion together, 
 and that all the inferences, which we can draw from 
 one to another, are founded merely on our experience 
 of their constant and regular conjunction ; it is evi- 
 dent^ that we ought not to make an exception to this 
 maxim in favour of human testimony, whose connexion 
 with any event seems, in itself, as little necessary as 
 any other. Were not the memory tenacious to a cer- 
 tain degree; had not men commonly an inclination to 
 truth and a principle of probity, were they not sensible 
 to shame, when detected in a falsehood : Were not 
 these, I say, discovered by experience to be qualities, 
 inherent in human nature, we should never repose the 
 least confidence in human testimony. A man deliri- 
 ous, or noted for falsehood and villany, has no manner 
 of authority with us. 
 
 And as the evidence, derived from witnesses and 
 human testimony, is founded on past experience, so it 
 varies with the experience, and is regarded either as 
 proof QX. di. probability i according as the conjunction be- 
 tween any particular kind of report and any kind of 
 object has been found to be constant or variable. / 
 There are a number of circumstances to be taken into 
 consideration in all judgements of this kind ; and the 
 ultimate standard, by which we determine all disputes, 
 that may arise concerning them, is always derived from 
 experience and observation. Where this experience 
 is not entirely uniform on any side, it is attended with 
 an unavoidable contrariety in our judgements, and 
 with the same opposition and mutual destruction of 
 argument as in every other kind of evidence. We fre- 
 
ii8 AN ENQ UIR Y CONCERNING 
 
 quently hesitate concerning the reports of others. We 
 balance the opposite circumstances, which cause any 
 doubt or uncertainty; and when we discover a superi- 
 ority on one side, we incline to it; but still with a 
 diminution of assurance, in proportion to the force of 
 its antagonist. 
 
 . This contrariety of evidence, in the present case, 
 may be derived from several different causes; from the 
 opposition of contrary testimony ; from the character 
 or number of the witnesses ; from the manner of their 
 delivering their testimony; or from the union of all 
 these circumstances. We entertain a suspicion con- 
 cerning any matter of fact, when the witnesses con- 
 tradict each other; when they are but few, or of a 
 doubtful character; when they have an interest in 
 what they affirm ; when they deliver their testimony 
 with hesitation, or on the contrary, with too violent 
 asseverations. There are many other particulars of 
 the same kind, which may diminish ar destroy the 
 force of any argument, derived from human testimony. 
 Suppose, for instance, that the fact, which the tes- 
 timony endeavours to establish, partakes of the extra- 
 ordinary and the marvellous; in that case, the evidence, 
 resulting from the testimony, admits of a diminution, 
 greater or less, in proportion as the fact is more or less 
 unusual. The reason why we place any credit in wit- 
 nesses and historians, is not derived from any connex- 
 ion, which we perceive a priori, between testimony and 
 reality, but because we are accustomed to find a con- 
 formity between them. But when the fact attested is 
 such a one as has seldom fallen under our observation, 
 here is a contest of two opposite experiences; of which 
 the one destroys the other, as far as its force goes, 
 and the superior can only operate on the mind by the 
 
HUMAN UNDERSTANDING. 119 
 
 force, which remains. The very same principle of 
 experience, which gives us a certain degree of assur- 
 ance in the testimony of witnesses, gives us also, in 
 this case, another degree of assurance against the fact, 
 which they endeavour to establish; from which contra- 
 diction there necessarily arises a counterpoize, and , ^ 
 mutual destruction of belief and authority. 
 
 / should not believe such a story were it told me by 
 Cato, was a proverbial saying in Rome, even during 
 the lifetime of that philosophical patriot.^ The in- 
 credibility of a fact, it was allowed, might invalidate 
 so great an authority. 
 
 The Indian prince, who refused to believe the first 
 relations concerning the effects of frost, reasoned justly; 
 and it naturally required very strong testimony to en- 
 gage his assent to facts, that arose from a state of 
 nature, with which he was unacquainted, and which 
 bore so little analogy to those events, of which he had 
 had constant and uniform experience. Though they 
 were not contrary to his experience, they were not 
 conformable to it.^ 
 
 1 Plutarch, in vita Catonis. 
 
 2 No Indian, it is evident, could have experience that water did not freeze 
 in cold climates. This is placing nature in a situation quite unknown to him; 
 and it is impossible for him to tell a priori what will result from it. It is 
 making a new experiment, the consequence of which is always uncertain. 
 One may sometimes conjecture from analogy what will follow ; but still this 
 is but conjecture. And it must be confessed, that, in the present case of 
 freezing, the event follows contrary to the rules of analogy, and is such as a 
 rational Indian would not look for. The operations of cold upon water are 
 not gradual, according to the degrees of cold ; but whenever it comes to the 
 freezing point, the water passes in a moment, from the utmost liquidity to 
 perfect hardness. Such an event, therefore, may be denominated extraordi- 
 nary, and requires a pretty strong testimony, to render it credible to people 
 in a warm climate : But still it is not miraculous, nor contrary to uniform ex- 
 perience of the course of nature in cases where all the circumstances are the 
 same. The inhabitants of Sumatra have always seen water fluid in their own 
 climate, and the freezing of their rivers ought to be deemed a prodigy: But 
 they never saw water in Muscovy during the winter; and therefore they can- 
 not reasonably be positive what would there be the consequence. 
 
120 AN ENQ UIR Y CONCERNING 
 
 But in order to encrease the probability against 
 the testimony of witnesses, let us suppose, that the 
 fact, which they affirm, instead of being only marvel- 
 lous, is really miraculous; and suppose also, that the 
 testimony considered apart and in itself, amounts to 
 an entire proof; in that case, there is proof against 
 proof, of which the strongest must prevail, but still 
 with a diminution of its force, in proportion to that of 
 its antagonist. . , , . 
 
 A miracle is a violation of the laws of nature ; and 
 as It firm and unalterable experience has established 
 these laws, the proof against a miracle, from the very 
 nature of the fact, is as entire as any argument from 
 experience can possibly be imagined. Why is it more 
 than probable, that all men must die ; that lead can- 
 not, of itself, remain suspended in the air; that fire 
 consumes wood, and is extinguished by water ; unless 
 it be, that these events are found agreeable to the laws 
 of nature, and there is required a violation of these 
 laws, or in other words, a miracle to prevent them ? 
 Nothing is esteemed a miracle, if it ever happen in 
 the common course of nature. It is no miracle that a 
 man, seemingly in good health, should die on a sud- 
 den : because such a kind of death, though more un- 
 usual than any other, has yet been frequently observed 
 to happen. But it is a miracle, that a dead man should 
 come to life ; because that has never been observed in 
 any age or country. There must, therefore, be a uni- 
 form experience against every miraculous event, other- 
 wise the event would not merit that appellation. And 
 as a uniform experience amounts to a proof, there is 
 here a direct and full proof, from the nature of the fact, 
 against the existence of any miracle ; nor can such a 
 
HUMAN UNDERSTANDING. 121 
 
 proof be destroyed, or the miracle rendered credible, 
 but by an opposite proof, which is superior.^ 
 
 The plain consequence is (and it is a general maxim 
 worthy of our attention), 'That no testimony is suffi- 
 cient to establish a miracle, unless the testimony be 
 of such a kind, that its falsehood would be more mi- 
 raculous, than the fact, which it endeavours to estab- 
 lish ; and even in that case there is a mutual destruc- 
 tion of arguments, and the superior only gives us an 
 assurance suitable to that degree of force, which re- 
 mains, after deducting the inferior.' When anyone 
 tells me, that he saw a dead man restored to life, I 
 immediately consider with myself, whether it be more 
 probable, that this person should either deceive or be 
 deceived, or that the fact, which he relates, should 
 really have happened. I weigh the one miracle against 
 the other ; and according to the superiority, which I 
 discover, I pronounce my decision, and always reject 
 the greater miracle. If the falsehood of his testimony 
 would be more miraculous, than the event which he 
 
 1 Sometimes an event may not, in itself ^ seem to be contrary to the laws 
 of nature, and yet, if it were real, it might, by reason of some circumstances, 
 be denominated a miracle ; because, in fact, it is contrary to these laws. 
 Thus if a person, claiming a divine authority, should command a sick person 
 to be well, a healthful man to fall down dead, the clouds to pour rain, the 
 winds to blow, in short, should order many natural events, which immediately 
 follow upon his command ; these might justly be esteemed miracles, because 
 they are really, in this case, contrary to the laws of nature. For if any suspi- 
 cion remain, that the event and command concurred by accident, there is no 
 miracle and no transgression of the laws of nature. If this suspicion be re- 
 moved, there is evidently a miracle, and a transgression of these laws; be- 
 cause nothing can be more contrary to nature than that the voice or command 
 of a man should have such an influence. A miracle may be accurately defined, 
 a transgression of a law of nature by a particular volition of the Deity, or by 
 the interposition of some invisible agent. A miracle may either be discoverable 
 by men or not. This alters not its nature and essence. The raising of a 
 house or ship into the air is a visible miracle. The raising of a feather, when 
 the wind wants ever so little of a force requisite for that purpose, is as real a 
 miracle, though not so sensible with regard to us. 
 
122 AN ENQ UIR Y CONCERNING 
 
 relates; then, and not till then, can he pretend to 
 command my belief or opInionry^^tiX %i-\'\\ u^ou- r>^ai.h 
 
 Part II. 
 
 In the foregoing reasoning we have supposed, that 
 the testimony, upon which a miracle is founded, may 
 possibly amount to' an entire proof, and that the false- 
 hood of that testimony would be a real prodigy : But 
 it is easy to shew, that we have been a great deal too 
 liberal in our concession, and that there never was av._, 
 miraculous event established on so full an evidence. 
 
 For Jirst, there is not to be found, in all history, 
 any miracle attested by a sufficient number of men, of 
 such unquestioned good-sense, education, and learn- 
 ing, as to secure us against all delusion in themselves; 
 of such undoubted integrity, as to place them beyond 
 all suspicion of any design to deceive others ; of such 
 credit and reputation in the eyes of mankind, as to 
 have a great deal to lose in case of their being detected 
 in any falsehood; and at the same time, attesting facts 
 performed in such a public manner and in so cele- 
 brated a part of the world, as to render the detection 
 unavoidable : All which circumstances are requisite 
 to give us a full assurance in the testimony of men. 
 
 Secondly. We may observe in human nature a prin- 
 ciple which, if strictly examined, will be found to di- 
 minish extremely the assurance, which we might, from 
 human testimony, have, in any kind of prodigy. The 
 maxim, by which we commonly conduct ourselves in 
 our reasonings, is, that the objects, of which we have 
 no experience, resemble those, of which we have; 
 that what we have found to be most usual is always 
 most probable ; and that where there is an opposition 
 
HUMAN UNDERSTANDING, 123 
 
 3o\ -^-^-^ ^-^ - '• • -^ '-^ ■ 
 ^f arguments, we ought to give the preference to such 
 as are founded on the greatest number of past obser- 
 vations. But though, in proceeding by this rule, we 
 readily reject any fact which is unusual and incredible 
 in an ordinary degree ; yet in advancing farther, the 
 mind observes not always the same rule ; but when 
 anything is affirmed utterly absurd and miraculous, it 
 rather the more readily admits of such a fact, upon 
 account of that very circumstance, which ought to de- 
 stroy all its authority. The passion of surprise and 
 wonder, arising from miracles, being an agreeable emo- 
 tion, gives a sensible tendency towards the belief of 
 those events, from which it is derived. And this goes 
 so far, that even those who cannot enjoy this pleasure 
 immediately, nor can believe those miraculous events, 
 of which they are informed, yet love to partake of the 
 satisfaction at second-hand or by rebound, and place 
 a pride and delight in exciting the admiration of others. 
 With what greediness are the miraculous accounts 
 of travellers received, their descriptions of sea and 
 land monsters, their relations of wonderful adventures, 
 strange men, and uncouth manners ? But if the spirit 
 of religion join itself to the love of wonder, there is an 
 end of common sense ; and human testimony, in these 
 circumstances, loses all pretensions to authority. A 
 religionist may be an enthusiast, and imagine he sees 
 what has no reality : he may know his narrative to be 
 false, and yet persevere in it, with the best intentions 
 in the world, for the sake of promoting so holy a cause: 
 or even where this delusion has not place, vanity, ex- 
 cited by so strong a temptation, operates on him more 
 powerfully than on the rest of mankind in any other 
 circumstances ; and self-interest with equal force. His 
 auditors may not have, and commonly have not, suf- 
 
124 AN ENQ UIR Y CONCERNING 
 
 ficient judgement to canvass his evidence: what judge- 
 ment they have, they renounce by principle, in these 
 sublime and mysterious subjects : or if they were ever 
 so willing to employ it, passion and a heated imagina- 
 tion disturb the regularity of its operations. Their 
 credulity increases his impudence : and his impudence 
 overpowers their credulity. 
 
 Eloquence, when at its highest pitch, leaves little 
 room for reason or reflection; but addressing itself 
 entirely to the fancy or the affections, captivates the 
 willing hearers, and subdues their understanding. 
 Happily, this pitch it seldom attains. But what a 
 Tully or a Demosthenes could scarcely effect over a 
 Roman or Athenian audience, every Capuchin, every 
 itinerant or stationary teacher can perform over the 
 generality of mankind, and in a higher degree, by 
 touching such gross and vulgar passions. 
 
 The many instances of forged miracles, and proph- 
 ecies, and supernatural events, which, in all ages, 
 have either been detected by contrary evidence, or 
 which detect themselves by their absurdity, prove 
 sufficiently the strong propensity of mankind to the 
 extraordinary and the marvellous, and ought reason- 
 ably to beget a suspicion against all relations of this 
 kind. This is our natural way of thinking, even with 
 regard to the most common and most credible events. 
 For instance : There is no kind of report which rises 
 so easily, and spreads so quickly, especially in country 
 places and provincial towns, as those concerning mar- 
 riages; insomuch that two young persons of equal 
 condition never see each other twice, but the whole 
 neighbourhood immediately join them together. The 
 pleasure of telling a piece of news so interesting, of 
 propagating it, and of being the first reporters of it, 
 
HUMAN UNDERSTANDING. 125 
 
 Spreads the intelligence. And this is so well known, 
 that no man of sense gives attention to these reports, 
 till he find them confirmed by some greater evidence. 
 Do not the same passions, and others still stronger, 
 incline the generality of mankind to believe and report, 
 with the greatest vehemence and assurance, all reli- 
 gious miracles ? 
 
 Thirdly, It forms a strong presumption against 
 all supernatural and miraculous relations, that they 
 are observed chiefly to abound among ignorant and 
 barbarous nations ; or if a civilized people has ever 
 given admission to any of them, that people will be 
 found to have received them from ignorant and bar- 
 barous ancestors, who transmitted them with that in- 
 violable sanction and authority, which always; attend 
 received opinions.. When we peruse the first histories 
 of all nations, we are apt to imagine ourselves trans- 
 ported into some new world ; where the whole frame 
 of nature is disjointed, and every element performs its 
 operations in a different manner, from what it does at 
 present. Battles, revolutions, pestilence, famine and 
 death, are never the effect of those natural causes, 
 which we experience. Prodigies," omens, oracles, 
 judgements, quite obscure the few natural events, that 
 are intermingled with them. But as the former grow 
 thinner every page, in proportion as we advance nearer 
 the enlightened ages, we soon learn, that there is noth- 
 ing mysterious or supernatural in the case, but that 
 all proceeds from the usual propensity of mankind 
 towards the marvellous, and that, though this inclina- 
 tion may at intervals receive a check from sense and 
 learning, it can never be thoroughly extirpated from 
 human nature. 
 
 // is strange^ a judicious reader is apt to say, upon 
 
125 AN ENQ UIR V CONCERNING 
 
 the perusal of these wonderful historians, that such 
 prodigious events never happen in our days. But it is 
 nothing strange, I hope, that men should lie in all 
 ages. You must surely have seen instances enough 
 of that frailty. You have yourself heard many such 
 marvellous relations started, which, being treated with 
 scorn by all the wise and judicious, have at last been 
 abandoned even by the vulgar. Be assured, that those 
 renowned lies, which have spread and flourished to 
 such a monstrous height, arose from like beginnings ; 
 but being sown in a more proper soil, shot up at last 
 into prodigies almost equal to those which they relate. 
 
 It was a wise policy in that false prophet, Alexan- 
 der, who though now forgotten, was once so famous, 
 to lay the first scene of his impostures in Paphlagonia, 
 where, as Lucian tells us, the people were extremely 
 ignorant and stupid, and ready to swallow even the 
 grossest delusion. People at a distance, who are weak 
 enough to think the matter at all worth enquiry, have 
 no opportunity of receiving better information. The 
 stories come magnified to them by a hundred circum- 
 stances. Fools are industrious in propagating the 
 imposture ; while the wise and learned are contented, 
 in general, to deride its absurdity, without informing 
 themselves of the particular facts, by which it may be 
 distinctly refuted. And thus the impostor above men- 
 tioned was enabled to proceed, from his ignorant 
 Paphlagonians, to the enlisting of votaries, even among 
 the Grecian philosophers, and men of the most emi- 
 nent rank and distinction in Rome : nay, could engage 
 the attention of that sage emperor Marcus Aurelius; 
 so far as to make him trust the success of a military 
 expedition to his deluisve prophecies. 
 
 The advantages are so great, of starting an impos- 
 
HUMAN- UNDERSTANDING. 127 
 
 ture among an ignorant people, that, even though the 
 delusion should be too gross to impose on the gener- 
 ality of them {which, though seldom, is sometimes the case) 
 it has a much better chance for succeeding in remote 
 countries, than if the first scene had been laid in a city- 
 renowned for arts and knowledge. The most ignorant 
 and barbarous of these barbarians carry the report 
 abroad. None of their countrymen have a large cor- 
 respondence, or sufficient credit and authority to con- 
 tradict and beat down the delusion. Men's inclination 
 to the marvellous has full opportunity to display itself. 
 And thus a story, which is universally exploded in the 
 place where it was first started, shall pass for certain 
 at a thousand miles distance. But had Alexander 
 fixed his residence at Athens, the philosophers of that 
 renowned mart of learning had immediately spread, 
 throughout the whole Roman empire, their sense of 
 the matter ; which, being supported by so great au- 
 thority, and displayed by all the force of reason and 
 eloquence, had entirely opened the eyes of mankind. 
 It is true ; Lucian, passing by chance through Paph- 
 lagonia, had an opportunity of performing this good 
 office. But, though much to be wished, it does not 
 always happen, that every Alexander meets with a 
 Lucian, ready to expose and detect his impostures. 
 
 I may add as a /^z/rM reason, which diminishes the 
 authority of prodigies^ that there is no testimony for 
 any, even those which have not been expressly de- 
 tected, that is not opposed by an infinite number of 
 witnesses ; so that not only the miracle destroys the 
 credit of testimony, but the testimony destroys itself. 
 To make this the better understood, let us consider, 
 that, in matters of religion, whatever is different is 
 contrary; and that it is impossible the religions of 
 
128 AN" ENQ UIR V CONCERNING 
 
 ancient Rome, of Turkey, of Siam, and of China 
 should, all of them, be established on any solid foun- 
 dation. Every miracle, therefore, pretended to have 
 been wrought in any of these religions (and all of them 
 abound in miracles), as its direct scope is to establish 
 the particular system to which it is attributed ; so has 
 it the same force, though more indirectly, to overthrow 
 every other system. In destroying a rival system, it 
 likewise destroys the credit of those miracles, on which 
 that system was established; so that all the prodigies 
 of different religions are to be regarded as contrary 
 facts, and the evidences of these prodigies, whether 
 weak or strong, as opposite to each other. According 
 to this method of reasoning, when we believe any mir- 
 acle of Mahomet or his successors, we have for our 
 warrant the testimony of a few barbarous Arabians : 
 And on the other hand, we are to regard the authority 
 of Titus Livius, Plutarch, Tacitus, and, in short, of 
 all the authors and witnesses, Grecian, Chinese, and 
 Roman Catholic, who have related any miracle in their 
 particular religion ; I say, we are to regard their testi- 
 mony in the same light as if they had mentioned that 
 Mahometan miracle, and had in express terms contra- 
 dicted it, with the same certainty as they have for the 
 miracle they relate. This argument may appear over 
 subtile and refined ; but is not in reality different from 
 the reasoning of a judge, who supposes, that the credit 
 of two witnesses, maintaining a crime against any one, 
 is destroyed by the testimony of two others, who affirm 
 him to have been two hundred leagues distant, at the 
 same instant when the crime is said to have been com- 
 mitted. 
 
 One of the best attested miracles in all profane his- 
 tory, is that which Tacitus reports of Vespasian, who 
 
HUMAN UNDERSTANDING. 129 
 
 cured a blind man in Alexandria, by means oi his 
 spittle, and a lame man by the mere touch of his foot ; 
 in obedience to a vision of the god Serapis, who had 
 enjoined them to have recourse to the Emperor, for 
 these miraculous cures. The story may be seen in that 
 fine historian ;i where every circumstance seems to 
 add weight to the testimony, and might be displayed 
 at large with all the force of argument and eloquence, 
 if any one were now concerned to enforce the evidence 
 of that exploded and idolatrous superstition. The 
 gravity, solidity, age, and probity of so great an em- 
 peror, v/ho, through the whole course of his life, con- 
 versed in a familiar manner with his friends and court- 
 iers, and never affected those extraordinary airs of 
 divinity assumed by Alexander and Demetrius. The 
 historian, a cotemporary writer, noted for candour and 
 veracity, and withal, the greatest and most penetrat- 
 ing genius, perhaps, of all antiquity; and so free fronj 
 any tendency to credulity, that he even lies under the 
 contrary imputation, of atheism and profaneness: The 
 persons, from whose authority he related the miracle, 
 of established character for judgement and veracity, 
 as we may well presume ; eye-witnesses of the fact, 
 and confirming their testimony, after the Flavian fam- 
 ily was despoiled of the empire, and could no longer 
 give any reward, as the price of a lie. Utrumque, qui 
 interfuerey nunc quoque memoranty postquam nullum vien- 
 dacio pretium. To which if we add the public nature 
 of the facts, as related, it will appear, that no evidence 
 can well be supposed stronger for so gross and so 
 palpable a falsehood. 
 
 There is also a memorable story related by Cardi- 
 
 1 Hist. lib. V. cap. 8. Suetonius gives nearly the same account in vita 
 Vesp. 
 
I30 AM ENQUIRY CONCERNING 
 
 nal de Retz, which may well deserve our consideration. 
 When that intriguing politician fled into Spain, to 
 avoid the persecution of his enemies, he passed through 
 Saragossa, the capital of Arragon, where he was shewn, 
 in the cathedral, a man, who had served seven years 
 as a doorkeeper, and was well known to every body in 
 town, that had ever paid his devotions at that church. 
 He had been seen, for so long a time, wanting a leg ; 
 but recovered that limb by the rubbing of holy oil upon 
 the stump ; and the cardinal assures us that he saw 
 him with two legs. This miracle was vouched by all 
 the canons of the church ; and the whole company in 
 town were appealed to for a confirmation of the fact ; 
 whom the cardinal found, by their zealous devotion, 
 to be thorough believers of the miracle. Here the 
 relater was also cotemporary to the supposed prodigy, 
 of an incredulous and libertine character, as well as 
 of great genius ; the miracle of so singular a nature as 
 could scarcely admit of a counterfeit, and the witnesses 
 very numerous, and all of them, in a manner, specta- 
 tors of the fact, to which they gave their testimony. 
 And what adds mightily to the force of the evidence, 
 and may double our surprise on this occasion, is, that 
 the cardinal himself, who relates the story, seems not 
 to give any credit to it, and consequently cannot be 
 suspected of any concurrence in the holy fraud. He 
 considered justly, that it was not requisite, in order to 
 reject a fact of this nature, to be able accurately to 
 disprove the testimony, and to trace its falsehood, 
 through all the circumstances of knavery and credulity 
 which produced it. . He knew, that, as this was com- 
 monly altogether impossible at any small distance of 
 time and place; so was it extremely difficult, even 
 where one was immediately present, by reason of the 
 
HUMAN UNDERSTANDING 
 
 bigotry, ignorance, cunning, and roguery of ^.* ^at 
 part of mankind. He therefore concluded, like a just 
 reasoner, that such an evidence carried falsehood upon 
 the very face of it, and that a miracle, supported by 
 any human testimony, was more properly a subject of 
 derision than of argument. 
 
 There surely never was a greater number of mir- 
 acles ascribed to one person, than those, which were 
 lately said to have been wrought in France upon the 
 tomb of Abbd Paris, the famous Jansenist, with whose 
 sanctity the people were so long deluded. The curing 
 of the sick, giving hearing to the deaf, and sight to 
 the blind, were every where talked of as the usual ef- 
 fects of that holy sepulchre. But what is more extra- 
 ordinary; many of the miracles were immediately 
 proved upon the spot, before judges of unquestioned 
 integrity, attested by witnesses of credit and distinc- 
 tion, in a learned age, and on the most eminent the- 
 atre that is now in the world. Nor is this all : a rela- 
 tion of them was published and dispersed everywhere; 
 nor were the Jesuits ^ though a learned body, supported 
 by the civil magistrate, and determined enemies to 
 those opinions, in whose favour the miracles were said 
 to have been wrought, ever able distinctly to refute or 
 detect them. Where shall we find such a number of 
 circumstances, agreeing to the corroboration of one 
 fact? And what have we to oppose to such a cloud 
 of witnesses, but the absolute impossibility or miracu- 
 lous nature of the events, which they relate ? And this 
 surely, in the eyes of all reasonable people, will alone 
 be regarded as a sufficient refutation. 
 
 Is the consequence just, because some human tes- 
 timony has the utmost force and authority in some 
 cases, when it relates the battle of Philippi or Pharsa- 
 
AN- ENQUIR V CONCERNING 
 
 lia s^ i^nstance ; that therefore all kinds of testimony 
 must, in all cases, have equal force and authority? 
 Suppose that the Caesarean and Pompeian factions 
 had, each of them, claimed the victory in these bat- 
 tles, and that the historians of each party had uniformly 
 ascribed the advantage to their own side ; how could 
 mankind, at this distance, have been able to deter- 
 mine between them? The contrariety is equally strong 
 between the miracles related by Herodotus or Plutarch, 
 and those delivered by Mariana, Bede, or any monkish 
 historian. 
 
 The wise lend a very academic faith to every report 
 which favours the passion of the reporter; whether it 
 magnifies his country, his family, or himself, or in any 
 other way strikes in with his natural inclinations and 
 propensities. But what greater temptation than to 
 appear a missionary, a prophet, an ambassador from 
 heaven? Who would not encounter many dangers and 
 difficulties, in order to attain so sublime a character? 
 Or if, by the help of vanity and a heated imagination, 
 a man has first made a convert of himself, and entered 
 seriously into the delusion; who ever scruples to make 
 use of pious frauds, in support of so holy and merito- 
 rious a cause? 
 
 The smallest spark may here kindle into the great- 
 est flame ; because the materials are always prepared 
 for it. The avidum genus auricularum^^ the gazing 
 populace, receive greedily, without examination, what- 
 ever soothes superstition, and promotes wonder. 
 
 How many stories of this nature have, in all ages, 
 been detected and exploded in their infancy? How 
 many more have been celebrated for a time, and have 
 afterwards sunk into neglect and oblivion? Where 
 
 1 Lucret. 
 
HUMAN UNDERSTANDING. I33 
 
 such reports, therefore, fly about, the solution of the 
 phenomenon is obvious; and we judge in conformity 
 to regular experience and observation, when we ac- 
 count for it by the known and natural principles of 
 credulity and delusion. And shall we, rather than 
 have a recourse to so natural a solution, allow of a 
 miraculous violation of the most established laws of 
 nature? 
 
 I need not mention the difficulty of detecting a false- 
 hood in any private or even public history, at the 
 place, where it is said to happen ; much more when 
 the scene is removed to ever so small a distance. 
 Even a court of judicature, with all the authority, ac- 
 curacy, and judgement, which they can employ, find 
 themselves often at a loss to distinguish between truth 
 and falsehood in the most recent actions. But the 
 matter never comes to any issue, if trusted to the com- 
 mon method of altercations and debate and flying ru- 
 mours; especially when men's passions have taken part 
 on either side. 
 
 ^-^In the infancy of new religions, the wise and learned 
 corhmonly esteem the matter too inconsiderable to de- 
 serve their attention or regard. And when afterwards 
 they would willingly detect the cheat, in order to un- 
 deceive the deluded multitude, the season is now 
 past, and the records and witnesses, which might 
 clear up the matter, have perished beyond recovery. 
 
 No means of detection remain, but those which 
 must be drawn from the very testimony itself of the 
 reporters: and these, though always sufficient with 
 the judicious and knowing, are commonly too fine to 
 fall under the comprehension of the vulgar. 
 
 Upon the whole, then, it appears, that no testi- 
 mony for any kind of miracle has ever amounted to a 
 
134 ^^ ^^Q U^^ Y ^ ONCERNING 
 
 probability, much less to a proof; and that, even sup- 
 posing it amounted to a proof, it would be opposed 
 by another proof ; derived from the very nature of the 
 fact, which it would endeavour to establish. It is ex- 
 perience only, which gives authority to human testi- 
 mony; and it is the same experience, which assures us 
 of the laws of nature. When, therefore, these two klnds^ 
 of experience are contrary, we have nothing to do 
 but substract the one from the other, and embrace 
 an opinion, either on one side or the other, with that 
 assurance which arises from the remainder. But ac- 
 cording to the principle here explained, this substrac- 
 tion, with regard to all popular religions, amounts to 
 an entire annihilation ; and therefore we may establish 
 it as a maxim,' that no human testimony can have such 
 force as to prove a miracle, and make it a just foun- 
 dation for any such system of religion.- 
 
 I beg the limitations here made may be remarked, 
 when I say, that a miracle can never be proved, so as 
 to be the foundation of a system of religion. For I 
 own, that otherwise, there may possibly be miracles, 
 or violations of the usual course of nature, of such a 
 kind as to admit of proof from human testimony; 
 though, perhaps, it will be impossible to find any such 
 in all the records of history. Thus, suppose, all 
 authors, In all languages, agree, that, from the first of 
 January 1600, there was a total darkness over the whole 
 earth for eight days: suppose that the tradition of this 
 extraordinary event is still strong and lively among 
 the people: that all travellers, who return from foreign 
 countries, bring us accounts of the same tradition, 
 without the least variation or contradiction : it is evi- 
 dent, that our present philosophers, instead of doubt- 
 ing the fact, ought to receive It as certain, and ought 
 
HUMAN UNDERSTANDING 135 
 
 to search for the causes whence it might be derived. 
 The decay, corruption, and dissolution of nature, is 
 an event rendered probable by so many analogies, 
 that any phenomenon, which seems to have a tend- 
 ency towards that catastrophe, comes within the reach 
 of human testimony, if that testimony be very exten- 
 sive and uniform. 
 
 But suppose, that all the historians who treat of 
 England, should agree, that, on the first of Jan- 
 uary 1600, Queen Elizabeth died ; that both before 
 and after her death she was seen by her physicians 
 and the whole court, as is usual with persons of her 
 rank ; that her successor was acknowledged and pro- 
 claimed by the parliament ; and that, after being in- 
 terred a month, she again appeared, resumed the 
 throne, and governed England for three years: I must 
 confess that I should be surprised at the concurrence 
 of so many odd circumstances, but should not have 
 the least inclination to believe so miraculous an event. 
 I should not doubt of her pretended death, and of 
 those other public circumstances that followed it : I 
 should only assert it to have been pretended, and that 
 it neither was, nor possibly could be real. You would 
 in vain object to me the difficulty, and almost impos- 
 sibility of deceiving the world in an affair of such con- 
 sequence ; the wisdom and solid judgement of that 
 renowned queen j with the little or no advantage 
 which she could reap from so poor an artifice : All 
 this might astonish me ; but I would still reply, that 
 the knavery and folly of men are such common phe- 
 nomena, that I should rather believe the most extraor- 
 dinary events to arise from their concurrence, than 
 admit of so signal a violation of the laws of nature. 
 
 But should this miracle be ascribed to any new 
 
1 36 AN ENQ UIR V CONCERNING 
 
 system of religion; men, in all ages, have been so 
 much imposed on by ridiculous stories of that kind, 
 that this very circumstance would be a full proof of a 
 cheat, and sufficient, with all men of sense, not only 
 to make them reject the fact, but even reject it with- 
 out farther examination. Though the Being to whom 
 the miracle is ascribed, be, in this case, Almighty, it 
 does not, upon that account, become a whit more 
 probable ; since it is impossible for us to know the 
 attributes or actions of such a Being, otherwise than 
 from the experience which we have of his productions, 
 in the usual course of nature. This still reduces us 
 to past observation, and obliges us to compare the 
 instances of the violation of truth in the testimony of 
 men, with those of the violation of the laws of nature 
 by miracles, in order to judge which of them is most 
 likely and probable. As the violations of truth are 
 more common in the testimony concerning religious 
 miracles, than in that concerning any other matter of 
 fact ; this must diminish very much the authority of 
 the former testimony, and make us form a general 
 resolution, never to lend any attention to it, with 
 whatever specious pretence it may be covered. 
 
 Lord Bacon seems to have embraced the same 
 principles of reasoning. *We ought,* says he, *to 
 make a collection or particular history of all monsters 
 and prodigious births or productions, and in a word 
 of every thing new, rare, and extraordinary in nature. 
 But this must be done with the most severe scrutiny, 
 lest we depart from truth. Above all, every relation 
 must be considered as suspicious, which depends in 
 any degree upon religion, as the prodigies of Livy : 
 And no less so, every thing that is to be found in the 
 writers of natural magic or alchimy, or such authors, 
 
HUMAN UNDERSTANDING, 137 
 
 who seem> all of them, to have an unconquerable ap- 
 petite for falsehood and fable. ' ^ 
 
 I am the better pleased with the method of reason- 
 ing here delivered, as I think it may serve to confound 
 those dangerous friends or disguised enemies to the ' 
 Christian Religion^ who have undertaken to defend it 
 by the principles of human reason. Our most holy 
 religion is founded on Faith^ not on reason ; and it is , 
 a sure method of exposing it to put it tp such a trial y^u. o- 
 as it is, by no means, fitted to endure. To make this L . ^^ . 
 more evident, let us examine those miracles, related ^ 
 
 in scripture ; and not to lose ourselves in too wide a 
 field, let us confine ourselves to such as we find in the 
 Pentateuchy which we shall examine, according to the 
 principles of these pretended Christians, not as the 
 word or testimony of God himself, but as the produc- 
 tion of a mere human writer and historian. ^Here then 
 we are first to consider a book, presented^to us by a 
 barbarous and ignorant people, written in an age when 
 they were still more barbarous, and in all probability 
 long after the facts which it relates, corroborated by 
 no concurring testimony, and resembling those fabu- 
 lous accounts, which every nation gives of its origin. 
 Upon reading this book, we find it full of prodigies 
 and miracles. It gives an account of a state of the 
 world and of human nature entirely different from the 
 present : Of our fall from that state : Of the age of 
 man, extended to near a thousand years : Of the de- 
 struction of the world by a deluge : Of the arbitrary 
 choice of one people, as the favourites of heaven ; and 
 that people the countrymen of the author : Of their 
 deliverance from bondage by prodigies the most aston- 
 ishing imaginable : I desire any one to lay his hand 
 
 1 Nov. Org. lib. ii. aph, 29. 
 
138 AN- ENQUIRY CONCERNING 
 
 upon his heart, and after a serious consideration de- 
 clare, whether he thinks that the falsehood of such a 
 book, supported by such a testimony, would be more 
 extraordinary and miraculous than all the miracles it 
 relates; which is, however, necessary to make it be 
 received, according to the measures of probability 
 above established. 
 
 . What we have said of miracles may be applied, 
 without any variation, to prophecies ; and indeed, all 
 prophecies are realjniracles, and as.such only, can be 
 admitted as proofs of any revelation. If it did not ex- 
 ceed the capacity of human nature to foretell future 
 events, it would be absurd to employ any prophecy as 
 an argument for a divine mission or authority from 
 heaven. So that, upon the whole, we may conclude, 
 that the Christian Religion not only was at first attended 
 with miracles, but even at this day cannot be believed 
 by any reasonable person without one. Mere reason 
 is insufficient to convince us of its veracity : And who- 
 ever is moved by Faith to assent to it, is conscious of 
 a continued miracle in his own person, which subverts 
 all the principles of his understanding, and gives him 
 a determination to believe what is most contrary tc5 
 custom and experience. 
 
SECTION XI. 
 
 OF A PARTICULAR PROVIDENCE AND OF A FUTURE 
 STATE. 
 
 I WAS lately engaged in conversation with a friend ''^^^ 4- ^- 
 who loves sceptical paradoxes ; where, though he 
 advanced many principles, of which I can by no means 
 approve, yet as they seem to be curious, and to bear 
 some relation to the chain of reasoning carried on 
 throughout this enquiry, I shall here copy them from 
 my memory as accurately as I can, in order to submit 
 them to the judgement of the reader. 
 
 Our conversation began with my admiring the sin- 
 gular good fortune of philosophy, which, as it requires 
 entire liberty above all other privileges, and chiefly 
 flourishes from the free opposition of sentiments and 
 argumentation, received its first birth in an age and 
 Country of freedom and toleration, and was never 
 cramped, even in its most extravagant principles, by 
 any creeds, concessions, or penal statutes. For, except 
 the banishment of Protagoras, and the death of Soc- 
 rates, which last event proceeded partly from other 
 motives, there are scarcely any instances to be met 
 with, in ancient history, of this bigotted jealousy, with 
 which the present age is so much infested. Epicurus 
 lived at Athens to an advanced age, in peace and tran- 
 quillity: Epicureans^ were even admitted to receive 
 the sacerdotal character, and to officiate at the altar, 
 
 ILuciani av/X7r. rj AanCBai, 
 
I40 AN ENQUIRY CONCERNING 
 
 in the most sacred rites of the established religion : 
 And the public encouragement ^ of pensions and sala- 
 ries was afforded equally, by the wisest of all the 
 Roman emperors, '^ to the professors of every sect of 
 philosophy. How requisite such kind of treatment 
 was to philosophy, in hgr early youth, will easily be 
 conceived, if we reflect, that, even at present, when 
 she may be supposed more hardy and robust, she bears 
 with much difficulty the inclemency of Jthe seasons, 
 and those harsh winds of calumny and persecution, 
 which blow upon her. 
 
 You admire, says my friend, as the singular good 
 fortune of philosophy, what seems to result from the 
 natural course of things, and to be unavoidable in 
 every age and nation. This pertinacious bigotry, of 
 which you complain, as so fatal to philosophy, is 
 really her offspring, who, after allying with supersti- 
 tion, separates himself entirely from the interest of 
 his parent, and becomes her most inveterate enemy 
 and persecutor. Speculative dogmas of religion, the 
 present occasions of such furious dispute, could not 
 possibly be conceived or admitted in the early ages of 
 the world; when mankind, being wholly illiterate, 
 formed an idea of religion more suitable to their weak 
 apprehension, and composed their sacred tenets of 
 such tales chiefly as were the objects of traditional 
 belief, more than of argument or disputation. After 
 the first alarm, therefore, was over, which aroje from 
 the new paradoxes and principles of the philosophers; 
 these teachers seem ever after, during the ages of 
 antiquity, to have lived in great harmony with the es- 
 tablished superstition, and to have made a fair parti- 
 
 \ Luciani evrovxof • ' Luciani and Dio. 
 
HUMAN UNDERSTANDING 141 
 
 tion of mankind between them ; the former claiming 
 all the learned and wise, the latter possessing all the 
 vulgar and illiterate. 
 
 It seems then, say I, that you leave politics entirely 
 out of the question, and never suppose, that a wise 
 magistrate can justly be jealous of certain tenets of 
 philosophy, such as those of Epicurus, which, denying 
 a divine existence, and consequently a providence and 
 a future state, seem to loosen, in a great measure, the 
 ties of morality, and may be supposed, for that reason, 
 pernicious to the peace of civil society. 
 
 I know, replied he, that in fact these persecutions 
 never, in any age, proceeded from calm reason, or from 
 experience of the pernicious consequences of philos- 
 ophy ; but arose entirely from passion and prejudice. 
 But what if I should advance farther, and assert, that 
 if Epicurus had been accused before the people, by 
 any of the sycophants or informers of those days, he 
 could easily have defended his cause, and proved his 
 principles of philosophy to be as salutary as those o^ 
 his adversaries, who endeavoured, v/ith such zeal, to 
 expose him to the public hatred and jealousy? 
 
 I wish, said I, you would try your eloquence upon 
 so extraordinary a topic, and make a speech for Epi- 
 curus, which might satisfy, not the mob of Athens, if 
 you will allow that ancient and polite city to have con- 
 tained any mob, but the more philosophical part of 
 his audience, such as might be supposed capable of 
 comprehending his arguments. 
 
 The matter would not be difficult, upon such condi- 
 tions, replied he : And if you please, I shall suppose 
 myself Epicurus for a moment, and make you stand 
 for the Athenian people, and shall deliver you such an 
 harangue as will fill all the urn with white beans, and 
 
143 AM ENQUIRY CONCERNING 
 
 leave not a black one to gratify the malice of my 
 adversaries. 
 
 Very well : Pray proceed upon these suppositions. 
 
 I come hither, O ye Athenians, to justify in your 
 assembly what I maintained in my school, and I find 
 myself impeached by furious antagonists, instead of 
 reasoning with calm and dispassionate enquirers. Your 
 deliberations, which of right should be directed to 
 questions of public good, and the interest of the com- 
 monwealth, are diverted to the disquisitions of spec- 
 ulative philosophy; and these magnificent, but per- 
 haps fruitless enquiries, take place of your more famil- 
 iar but more useful occupations. But so far as in me 
 lies, I will prevent this abuse. We shall not here dis- 
 pute concerning the origin and government of worlds. 
 We shall only enquire how far such questions concern 
 the public interest. And if I can persuade you, that 
 they are entirely indifferent to the peace of society and 
 security of government, I hope that you will presently 
 send us back to our schools, there to examine, at lei- 
 sure, the question the most sublime, but at the same 
 time, the most speculative of all philosophy. 
 
 The religious philosophers, not satisfied with the 
 tradition of your forefathers, and doctrine of your 
 priests (in which I willingly acquiesce), indulge a rash 
 curiosity, in trying how far they can establish religion 
 upon the principles of reason; and they thereby excite, 
 instead of satisfying, the doubts, which naturally arise 
 from a diligent and scrutinous enquiry. They paint, 
 in the most magnificent colours, the order, beauty, 
 and wise arrangement of the universe ; and then ask, 
 if such a glorious display of intelligence could proceed 
 from the fortuitous concourse of atoms, or if chance 
 could produce what the greatest genius can never suf- 
 
HUMAN UNDERSTANDING, 143 
 
 ficiently admire. I shall not examine the justness of 
 this argument. I shall allow it to be as solid as my 
 antagonists and accusers can desire. It is sufficient, 
 if I can prove, from this very reasoning, that the ques- 
 tion is entirely speculative, and that, when, in my phi- 
 losophical disquisitions, I deny a providence and a 
 future state, I undermine not the foundations of soci- 
 ety, but advance principles, which they themselves, 
 upon their own topics, if they argue consistently, must 
 allow to be solid and satisfactory. 
 
 You then, who are my accusers, have acknowledged^^ 
 that the chief or sole argument for a divine existence \ 
 (which I never questioned) is derived from the order 
 of nature ; where there appear such marks of intelli- 
 gence and design, that you think it extravagant to as- 
 sign for its cause, either chance, or the blind and un- 
 guided force of matter. You allow, that this is an"> 
 argument drawn from effects to causes. From the 
 order of the work, you infer, that there must have been 
 project and forethought in the workman. If you can- 
 not make out this point, you allow, that your conclu- 
 sion fails ; and you pretend not to establish the con- 
 clusion in a greater latitude than the phenomena of 
 nature will justify. These are your concessions. I 
 desire you to mark the consequences. 
 
 I When we infer any particular cause from an effect, 
 we must proportion the one to the other, and can never 
 be allowed to ascribe to the cause any qualities, but 
 what are exactly sufficient to produce the e ffect.! A 
 body of ten ounces raised in any scale may serve as a 
 proof, that the counterbalancing weight exceeds ten 
 ounces ; but can never afford a reason that it exceeds 
 a hundred. If the cause, assigned for any effect, be 
 not sufficient to produce it, we must either reject that 
 
144 ^^ ^^Q U^^ Y CONCERNING 
 
 cause, or add to it such qualities as will give it a just 
 proportion to the effect. But if we ascribe to it further 
 qualities, or affirm it capable of producing other 
 effects, we can only indulge the licence of conjecture, 
 and arbitrarily suppose the existence of qualities and 
 energies, without reason or authority. 
 
 The same rule holds, whether the cause assigned 
 be brute unconscious matter, or a rational intelligent 
 being. If the cause be known only by the effect, we 
 never ought to ascribe to it any qualities, beyond what 
 are precisely requisite to produce the effect : Nor can 
 we, by any rules of just reasoning, return back from 
 the cause, and infer other effects from it, beyond those 
 by which alone it is known to us. No one, merely 
 from the sight of one of Zeuxis's pictures, could know, 
 that he was also a statuary or architect, and was an 
 artist no less skilful in stone and marble than in col- 
 ours. The talents and taste, displayed in the partic- 
 ular work before us; these we may safely conclude 
 the workman to be possessed of. The cause must be 
 proportioned to the effect ; and if we exactly and pre- 
 cisely proportion it, we shall never find in it any 
 qualities, that point farther, or afford an inference 
 concerning any other design or performance. Such 
 qualities must be somewhat beyond what is merely 
 requisite for producing the effect, which we examine. 
 
 Allowing, therefore, the gods to be the authors of 
 the existence or order of the universe \ it follows, that 
 they possess that precise degree of power, intelligence, 
 and benevolence, which appears in their workmanship; 
 but nothing farther can ever be proved, except we call 
 in the assistance of exaggeration and flattery to supply 
 the defects of argument and reasoning. So far as the 
 traces of any attributes, at present, appear, so far may 
 
HUMAN UNDERSTANDING. 145 
 
 we conclude these attributes to exist. The supposition 
 of farther attributes is mere hypothesis ; much more 
 the supposition, that, in distant regions of space or 
 periods of time, there has been, or will be, a more mag- 
 nificent display of these attributes, and a scheme of 
 administration more suitable to such imaginary vir- 
 tues. We can never be allowed to mount up from the 
 universe, the effect, to Jupiter, the cause ; and then 
 descend downwards, to infer any new effect from that 
 cause ; as if the present effects alone were not entirely 
 worthy of the glorious attributes, which we ascribe to 
 that deity. The knowledge of the cause being derived 
 solely from the effect, they must be exactly adjusted 
 to each other; and the one can never refer to anything 
 farther, or be the foundation of any new inference and 
 conclusion. 
 
 You find certain phenomena in nature. You seek 
 a cause or author. You imagine that you have found 
 him. You afterwards become so enamoured of this off- 
 spring of your brain, that you imagine it impossible, 
 but he must produce something greater and more per- 
 fect than the present scene of things, which is so full 
 of ill and disorder. You forget, that this superlative 
 intelligence and benevolence are entirely imaginary, 
 or, at least, without any foundation in reason ; and 
 that you have no ground to ascribe to him any quali- 
 ties, but what you see he has actually exerted and dis- 
 played in his productions. Let your gods, therefore, 
 O philosophers, be suited to the present appearances 
 of nature: and presume not to alter these appearances 
 by arbitrary suppositions, in order to suit them to the 
 attributes, which you so fondly ascribe to your deities. 
 
 When priests and poets, supported by your author- 
 ity, O Athenians, talk of a golden or silver age, which 
 
146 AN ENQ UIR Y CONCERNING 
 
 preceded the present state of vice and misery, I hear 
 them with attention and with reverence. But when 
 philosophers, who pretend to neglect authority, and 
 to cultivate reason, hold the same discourse, I pay 
 them not, I own, the same obsequious submission and 
 pious deference. I ask, who carried them into the 
 celestial regions, who admitted them into the coun- 
 cils of the gods, who opened to them the book of fate, 
 that they thus rashly affirm, that their deities have 
 executed, or will execute, any purpose beyond what 
 has actually appeared ? If they tell me, that they have 
 mounted on the steps or by the gradual ascent of 
 reason, and by drawing inferences from effects to 
 causes, I still insist, that they have aided the ascent 
 of reason by the wings of imagination; otherwise they 
 could not thus change their manner of inference, and 
 argue from causes to effects ; presuming, that a more 
 perfect production than the present world would be 
 more suitable to such perfect beings as the gods, and 
 forgetting that they have no reason to ascribe to these 
 celestial beings any perfection or any attribute, but 
 what can be found in the present world. 
 
 Hence all the fruitless industry to account for the 
 ill appearances of nature, and save the honour of the 
 gods ; while we must acknowledge the reality of that 
 evil and disorder, with which the world so much 
 abounds. The obstinate and intractable qualities of 
 matter, we are told, or the observance of general laws, 
 or some such reason, is the sole cause, which controlled 
 the power and benevolence of Jupiter, and obliged 
 him to create mankind and every sensible creature so 
 imperfect and so unhappy. These attributes then, 
 are, it seems, beforehand, taken for granted, in their 
 greatest latitude. And upon that supposition, I own 
 
HUMAN UNDERSTANDING. 147 
 
 that such conjectures may, perhaps, be admitted as 
 plausible solutions of the ill phenomena. But still I 
 ask. Why take these attributes for granted, or why 
 ascribe to the cause any qualities but what actually 
 appear in the effect ? Why torture your brain to jus- 
 tify the course of nature upon suppositions, which, for 
 aught you know, may be entirely imaginary, and of 
 which there are to be found no traces in the course of 
 nature ? 
 
 The religious hypothesis, therefore, must be con- 
 sidered only as a particular method of accounting for 
 the visible phenomena of the universe : but no just 
 reasoner will ever presume to infer from it any single 
 fact, and alter or add to the phenomena, in any single 
 particular. If you think, that the appearances of 
 things prove such causes, it is allowable for you to 
 draw an inference concerning the existence of these 
 causes. In such complicated and sublime subjects, 
 every one should be indulged in the liberty of conjec- 
 ture and argument. But here you ought to rest. If 
 you come backward, and arguing from your inferred 
 causes, conclude, that any other fact has existed, or 
 will exist, in the course of nature, which may serve as 
 a fuller display of particular attributes ; I must ad- 
 monish you, that you have departed from the method 
 of reasoning, attached to the present subject, and 
 have certainly added something to the attributes of 
 the cause, beyond what appears in the effect ; other- 
 wise you could never, with tolerable sense or pro- 
 priety, add anything to the effect, in order to render 
 it more worthy of the cause. 
 
 Where, then, is the odiousness of that doctine, 
 which I teach in my school, or rather, whicn I exam- 
 ine in my gardens ? Or what do you find in this 
 
148 AN ENQUIRY CONCERNING 
 
 whole question, wherein the security of good morals, 
 or the peace and order of society, is in the least con- 
 cerned ? 
 
 I deny a providence, you say, and supreme gov- 
 ernor of the world, who guides the course of events, 
 and punishes the vicious with infamy and disappoint- 
 ment, and rewards the virtuous with honour and suc- 
 cess, in all their undertakings. But surely, I deny 
 not the course itself of events, which lies open to 
 every one's inquiry and examination. I acknowledge, 
 that, in the present order of things, virtue is attended 
 with more peace of mind than vice, and meets with a 
 more favourable reception from the world. I am sen- 
 sible, that, according to the past experience of man- 
 kind, friendship is the chief joy of human life, and 
 moderation the only source of tranquillity and happi- 
 ness. I never balance between the virtuous and the 
 vicious course of life; but am sensible, that, to a well- 
 disposed mind, every advantage is on the side of the 
 former. And what can you say more, allowing all 
 your suppositions and reasonings ? You tell me, 
 indeed, that this disposition of things proceeds from 
 intelligence and design. But whatever it proceeds 
 from, the disposition itself, on which depends our 
 happiness or misery, and consequently our conduct 
 and deportment in life is still the same. It is still 
 open for me, as well as you, to regulate my behaviour, 
 by my experience of past events. And if you affirm, 
 that, while a divine providence is allowed, and a su- 
 preme distributive justice in the universe, I ought to 
 expect some more particular reward of the good, and 
 punishment of the bad, beyond the ordinary course of 
 events; I here find the same fallacy, which I have 
 before endeavoured to detect. You persist in imagin- 
 
HUMAN UNDERSTANDING. 149 
 
 ing, that, if we grant that divine existence, for which 
 you so earnestly contend, you may safely infer conse- 
 quences from it, and add something to the experienced 
 order of nature, by arguing from the attributes which 
 you ascribe to your gods. You seem not to remember, 
 that all your reasonings on this subject can only be 
 drawn from effects to causes; and that every argu- 
 ment^ deducted from causes to effects, must of neces- 
 sity be a gross sophism; since it is impossible for you 
 to know anything of the cause, but what you have 
 antecedently, not inferred, but discovered to the full, 
 in the effect. 
 
 But what must a philosopher think of those vain 
 reasoners, who, instead of regarding the present scene 
 of things as the sole object of their contemplation, so 
 far reverse the whole course of nature, as to render 
 this life merely a passage to something farther; a 
 porch, which leads to a greater, and vastly different 
 building ; a prologue, which serves only to introduce 
 the piece, and give it more grace and propriety? 
 Whence, do you think, can such philosophers derive 
 their idea of the gods? From their own conceit and 
 imagination surely. For if they derived it from the 
 present phenomena, it would never point to anything 
 farther, but must be exactly adjusted to them. That 
 the divinity may possibly be endowed with attributes, 
 which we have never seen exerted ; may be governed 
 by principles of action, which we cannot discover to 
 be satisfied : all this will freely be allowed. But still 
 this is mere possibility and hypothesis. We never can 
 have reason to infer any attributes, or any principles 
 of action in him, but so far as we know them to have 
 been exerted and satisfied. 
 
 Are there any marks of a distributive justice in the 
 
I50 AN ENQUIR V CONCERNING 
 
 world ? If you answer in the affirmative, I conclude, 
 that, since justice here exerts itself, it is satisfied. If 
 you reply in the negative, I conclude, that you have 
 then no reason to ascribe justice, in our sense of it, 
 to the gods. If you hold a medium between affirma- 
 tion and negation, by saying, that the justice of the 
 gods, at present, exerts itself in part, but not in its full 
 extent; I answer, that you have no reason to give it 
 any particular extent, but only so far as you see it, at 
 present, exert itself. 
 
 Thus I bring the dispute, O Athenians, to a short 
 issue with my antagonists. The course of nature lies 
 open to my contemplation as well as to theirs. The 
 experienced train of events is the great standard, by 
 which we all regulate our conduct. Nothing else can 
 be appealed to in the field, or in the senate. Nothing 
 else ought ever to be heard of in the school, or in the 
 closet. In vain would our limited understanding break 
 through those boundaries, which are too narrow for 
 our fond imagination. While we argue from the course 
 of nature, and infer a particular intelligent cause, 
 which first bestowed, and still preserves order in the 
 universe, we embrace a principle, which is both un- 
 certain and useless. It is uncertain; because the sub- 
 ject lies entirely beyond the reach of human experi- 
 ence. It is useless ; because our knowledge of this 
 cause being derived entirely from the course of nature, 
 we can never, according to the rules of just reasoning, 
 return back from the cause with any new inference, 
 or making additions to the common and experienced 
 course of nature, establish any new principles of con- 
 duct and behaviour. 
 
HUMAN UNDERSTANDING. 15X 
 
 I observe (said I, finding he had finished his ha. 
 rangue) that you neglect not the artifice of the dema- 
 gogues of old ; and as you were pleased to make me 
 stand for the people, you insinuate yourself into my 
 favour by embracing those principles, to which, you 
 know, I have always expressed a particular attach- 
 ment. But allowing you to make experience (as in- 
 deed I think you ought) the only standard of our 
 judgement concerning this, and all other questions of 
 fact ; I doubt not but, from the very same experience, 
 to which you appeal, it may be possible to refute this 
 reasoning, which you have put into the mouth of Epi- 
 curus. If you saw, for instance, a half-finished build- 
 ing, surrounded with heaps of brick and stone and 
 mortar, and all the instruments of masonry; could you 
 not infer from the effect, that it was a work of design 
 and contrivance ? And could you not return again, 
 from this inferred cause, to infer new additions to the 
 effect, and conclude, that the building would soon be 
 finished, and receive all the further improvements, 
 which art could bestow upon it ? If you saw upon 
 the sea-shore the print of one human foot, you would 
 conclude, that a man had passed that way, and that 
 he had also left the traces of the other foot, though 
 effaced by the rolling of the sands or inundation of the 
 waters. Why then do you refuse to admit the same 
 method of reasoning with regard to the order of na- 
 ture? Consider the world and the present life only as 
 an imperfect building, from which you can infer a su- 
 perior intelligence; and arguing from that superior 
 intelligence, which can leave nothing imperfect ; why 
 may you not infer a more finished scheme or plan, 
 which will receive its completion in some distant point 
 of space or time? Are not these methods of reasoning 
 
152 
 
 AN ENQUIRY CONCERNING 
 
 exactly similar? Ahd under what pretence can you 
 embrace the one, while you reject the other? 
 
 The infinite difference of the subjects, replied he, 
 is a sufficient foundation for this difference in my con- 
 clusions. In works of human art and contrivance, it is 
 allowable to advance from the effect to the cause, and 
 returning back from the cause, to form new inferences 
 concerning the effect, and examine the alterations, 
 which it has probably undergone, or may still undergo. 
 But what is the foundation of this method of reasoning? 
 Plainly this : that man is a being, whom we know by 
 experience, whose motives and designs we are ac- 
 quainted with, and whose projects and inclinations 
 have a certain connexion and coherence, according to 
 the laws which nature has established for the govern- 
 ment of such a creature. When, therefore, we find, 
 that any work has proceeded from the skill and indus- 
 try of man ; as we are otherwise acquainted with the 
 nature of the animal, we can draw a hundred infer- 
 ences concerning what may be expected from him ; 
 and these inferences will all be founded in experience 
 and observation. But did we know man only from 
 the single work or production which we examine, it 
 were impossible for us to argue in this manner; be- 
 cause our knowledge of all the qualities, which we 
 ascribe to him, being in that case derived from the 
 production, it is impossible they could point to any- 
 thing further, or be the foundation of any new infer- 
 ence. The print of a foot in the sand can only prove, 
 when considered alone, that there was some figure 
 adapted to it, by which it was produced: but the print 
 of a human foot proves likewise, from our other expe- 
 rience, that there was probably another foot, which 
 also left its impression, though effaced by time or 
 
HUMAN UNDERSTANDING 153 
 
 Other accidents. Here we mount from the effect to 
 the cause; and descending again from the cause, infer 
 alterations in the effect \ but this is not a continuation 
 of the same simple chain of reasoning. We compre- 
 hend in this case a hundred other experiences and 
 observations, concerning the usual figure and members 
 of that species of animal, without which this method 
 of argument must be considered as fallacious and 
 sophistical. 
 
 The case is not the same with our reasonings from 
 the works of nature. The Deity is known to us only 
 by his productions, and is a single being in the uni- 
 verse, not comprehended under any species or genus, 
 from whose experienced attributes or qualities, we can, 
 by analogy, infer any attribute or quality in him. As 
 the universe shews wisdom and goodness, we infer 
 wisdom and goodness. As it shews a particular de- 
 gree of these perfections, we infer a particular degree 
 of them, precisely adapted to the effect which we ex- 
 amine. But further attributes or further degrees of 
 the same attributes, we can never be authorised to 
 infer or suppose, by any rules of just reasoning. Now, 
 without some such license of supposition, it is impos- 
 sible for us to argue from the cause, or infer any alter- 
 ation in the effect, beyond what has immediately fallen 
 under our observation. Greater good produced by 
 this Being must still prove a greater degree of good- 
 ness : a more impartial distribution of rewards and 
 punishments must proceed from a greater regard to 
 justice and equity. Every supposed addition to the 
 works of nature makes an addition to the attributes of 
 the Author of nature; and consequently, being en- 
 tirely unsupported by any reason or argument, can 
 
\ 
 
 154 AN ENQUIRY CONCERNING 
 
 never be admitted but as mere conjecture and hy' 
 pothesis.^ 
 
 ' The great source of our mistake in this subject, 
 and of the unbounded licence of conjecture, which we 
 indulge, is, that we tacitly consider ourselves, as in 
 the place of the Supreme Being, and conclude, that 
 he will, on every occasion, observe the same conduct, 
 which we ourselves, in his situation, would have em- 
 braced as reasonable and eligible. But, besides that 
 the ordinary course of nature may convince us, that 
 almost everything is regulated by principles and max- 
 ims very different from ours; besides this, I say, it 
 must evidently appear contrary to all rules of analogy 
 to reason, from the intentions and project of men, tos 
 those of a Being so different, and so much superior. 
 In human nature, there is a certain experienced co- 
 herence of designs and inclinations; so that when, 
 from any fact, we have discovered one intention of 
 any man, it may often be reasonable, from experience, 
 to infer another, and draw a long chain of conclusions 
 concerning his past or future conduct. But this 
 
 1 In general, it may, I think, be established as a maxim, that where any 
 cause is known only by its particular effects, it must be impossible to infer 
 any new effects from that cause; since the qualities, which are requisite to 
 produce these new effects along with the former, must either be different, or 
 superior, or of more extensive operation, than those which simply produced 
 the effect, whence alone the cause is supposed to be known to us. We can 
 never, therefore, have any reason to suppose the existence of these qualities. 
 To say, that the new effects proceed only from a continuation of the same 
 energy, which is already known from the first effects, will not remove the 
 difficulty. For even granting this to be the case (which can seldom be sup- 
 posed), the very continuation and exertion of a like energy (for it is impos- 
 sible it can be absolutely the same), I say, this exertion of a like energy, in a 
 different period of space and time, is a very arbitrary supposition, and what 
 there cannot possibly be any traces of in the effects, from winch all our 
 knowledge of the cause is originally derived. Let the inferred cause be 
 exactly proportioned (as it should be) to the known effect ; and it is impos- 
 sible that it can possess any qualities, from which new or different effects can 
 be inferred. 
 
HUMAN UNDERSTANDING. 155 
 
 method of reasoning can never have place with regard 
 to a Being, so remote and incomprehensible, who 
 bears much less analogy to any other being in the uni- 
 verse than the sun to a waxen taper, and who dis- 
 covers himself only by some faint traces or outlines, 
 beyond which we have no authority to ascribe to him 
 any attribute or perfection. What we imagine to be 
 a superior perfection, may really be a defect. Or were 
 it ever so much a perfection, the ascribing of it to the 
 Supreme Being, where it appears not to have been 
 really exerted, to the full, in his works, savours more 
 of flattery and panegyric, than of just reasoning and 
 sound philosophy. All the philosophy, therefore, in 
 the world, and all the religion, which is nothing but a 
 species of philosophy, will never be able to carry us 
 beyond the usaal course of experience, or give us 
 measures of conduct and behaviour different from 
 those which are furnished by reflections on common 
 life. No new fact can ever be inferred from the reli- 
 gious hypothesis ; no event foreseen or foretold ; no 
 reward or punishment expected or dreaded, beyond 
 what is already known by practice and observation. 
 So that my apology for Epicurus will still appear 
 solid and satisfactory ; nor have the political interests 
 of society any connexion with the philosophical dis- 
 putes concerning metaphysics and religion. 
 
 There is still one circumstance, replied I, which 
 you seem to have overlooked. Though I should allow 
 your premises, I must deny your conclusion. You 
 conclude, that religious doctrines and reasonings can 
 have no influence on life, because they ought to have 
 no influence ; never considering, that men reason not 
 in the same manner you do, but draw many conse- 
 quences from the belief of a divine Existence, and sup- 
 
156 A17 ENQ UIR Y CONCERNING 
 
 pose that the Deity will inflict punishments on vice, 
 and bestow rewards on virtue, beyond what appear in 
 the ordinary course of nature. Whether this reason- 
 ing of theirs be just or not, is no matter. Its influence 
 on their life and conduct must still be the same. And, 
 those, who attempt to disabuse them of such preju- 
 dices, may, for aught I know, be good reasoners, but I 
 cannot allow them to be good citizens and politicians; 
 since they free men from one restraint upon their pas- 
 sions, and make the infringement of the laws of soci- 
 ety, in one respect, more easy and secure. 
 
 After all, I may, perhaps, agree to your general 
 conclusion in favour of liberty, though upon different 
 premises from those, on which you endeavour to found 
 it. I think, that the state ought to tolerate every 
 principle of philosophy; nor is there an instance, that 
 any government has suffered in its political interests 
 by such indulgence. There is no enthusiasm among 
 philosophers ; their doctrines are not very alluring to 
 the people ; and no restraint can be put upon their 
 reasonings, but what must be of dangerous conse- 
 quence to the sciences, and even to the state, by pav- 
 ing the way for persecution and oppression in points, 
 where the generality of mankind are more deeply in- 
 terested and concerned. 
 
 But there occurs to me (continued I) with regard 
 to your main topic, a difficulty, which I shall just pro- 
 pose to you without insisting on it ; lest it lead into 
 reasonings of too nice and delicate a nature. In a 
 word, I much doubt whether it be possible for a cause 
 to be known only by its effect (as you have all along 
 supposed) or to be of so singular and particular a na- 
 ture as to have no parallel and no similarity with any 
 other cause or object, that has ever fallen under our 
 
HUMAN UNDERSTANDING 157 
 
 observation J It is only when two species of objects are 
 found to be constantly conjoined, that we can infer 
 the one from the other ; and were an effect presented, 
 which was entirely singular, and could not be compre- 
 hended under any known species, I do not see, that we 
 could form any conjecture or inference at all concern- 
 ing its cause. If experience and observation and 
 analogy be, indeed, the only guides which we can rea- 
 sonably follow in inferences of this nature ; both the 
 effect and cause must bear a similarity and resemblance 
 to other effects and causes, which we know, and which 
 we have found, in many instances, to be conjoined 
 with each other. I leave it to your own reflection to 
 pursue the consequences of th'is principle. I shall just 
 observe, that, as the antagonists of Epicurus always 
 suppose the universe, an effect quite singular and un- 
 paralleled, to be the proof of a Deity, a cause no less 
 singular and unparalleled ; your reasonings, upon that 
 supposition, seem, at least, to merit our attention. 
 There is, I own, some difficulty, how we can ever re- 
 turn from the cause to the effect, and, reasoning from 
 our ideas of the former, infer any alteration on the 
 latter, or any addition to it. 
 
SECTION XII. 
 
 OF THE ACADEMICAL OR SCEPTICAL PHILOSOPHy 
 
 Part I. 
 
 THERE is not a greater number of philosophical 
 reasonings, displayed upon any subject, than 
 those, which prove the existence of a Deity, and refute 
 the fallacies of Atheists', and yet the most religious 
 philosophers still dispute whether any man can be so 
 blinded as to be a speculative atheist. How shall we 
 reconcile these contraditions? The knights-errant, 
 who wandered about to clear the world of dragons and 
 giants, never entertained the least doubt with regard 
 to the existence of these monsters. 
 
 The Sceptic is another enemy of religion, who nat- 
 urally provokes the indignation of all divines and 
 graver philosophers ; though it is certain, that no man 
 ever met with any such absurd creature, or conversed 
 with a man, who had no opinion or principle concern- 
 ing any subject, either of action,^ speculation. This 
 begets a very natural question j What is meant by a 
 sceptic? And how far is it possible to push these phil- 
 osophical principles of doubt and uncertainty ?_' 
 
 There is a species of scepticism, antecedent to all 
 study and philosophy, which is much inculcated by 
 Des Cartes and others, as a sovereign preservative 
 against error and precipitate judgement. It recom- 
 mends an universal doubt, not only of all our former 
 
HUMAN UNDERSTANDING. 159 
 
 opinions and principles, but also of our very faculties; 
 of whose veracity, say they, we must assure ourselves, 
 by a chain of reasoning, deduced from some original 
 principle, which cannot possibly be fallacious or de- | 
 ceitful. \ But neither is there any such original prin- 
 ciple, which has a prerogative above others, that are 
 self-evident and convincing : or if there were, could 
 we advance a step beyond it, but by the use of those 
 very faculties, of which we are supposed to be already 
 diffident. The Cartesian doubt, therefore, were it ever 
 possible to be attamed by any human creature (as it/i 
 plainly is not) would be entirely incurable; and no ' 
 reasoning could ever bring us to a state of assurance 
 and conviction upon any subject. 
 
 It must, however, be confessed, that this species 
 of scepticism, when more moderate, may be understood 
 in a very reasonable sense, and is a necessary prepar- 
 ative to the study of philosophy, by preserving a proper 
 impartiality in our judgements, and weaning our mind 
 from all those prejudices, which we may have imbibed 
 from education or rash opinion. To begin with clear 
 and self-evident principles, to advance by timorous 
 and sure steps, to review frequently our conclusions, 
 and examine accurately all their consequences; though 
 by these means we shall make both a slow and a short 
 progress in our systems ; are the only methods, by 
 which we can ever hope to reach truth, and attain a 
 proper stability and certainty in our determinations. 
 
 There is another species of scepticism, consequent 
 to science and enquiry, when men are supposed to 
 have discovered either the absolute fallaciousness of 
 their mental faculties, or their unfitness to reach any 
 fixed determination in all those curious subjects of 
 speculation, about which they are commonly em- 
 
i 
 
 x6o Air ENQUIRY CONCERNING 
 
 ployed. Even our very senses are brought into dis- 
 pute, by a certain species of philosophers; and the 
 maxims of common life are subjected to the same 
 doubt as the most profound principles or conclusions 
 of metaphysics and theology. As these paradoxical 
 tenets (if they may be called tenets) are to be met w^ith 
 in some philosophers, and the refutation of them in 
 several, they naturally excite our curiosity, and make 
 us enquire into the arguments, on which they may be 
 founded. 
 
 / I need not insist upon the more trite topics, em- 
 ployed by the sceptics in all ages, against the evidence 
 of sense; such as those which are derived from the im- 
 perfection and fallaciousness of our organs, on num- 
 berless occasions ; the crooked appearance of an oar 
 in water; the various aspects of objects, according to 
 their different distances; the double images which 
 arise from the pressing one eye; with many other 
 iappearances of a like nature. These sceptical topics, 
 lindeed, are only sufficient to prove, that the senses 
 'alone are not implicitly to be depended on; but that 
 we must correct their evidence by reason, and by con- 
 siderations, derived from the nature of the medium, 
 the distance of the object, and the disposition of the 
 organ, in order to render them, within their sphere, 
 the proper criteria of truth and falsehood. There are 
 other more profound arguments against the senses, 
 which admit not of so easy a solution. 
 
 It seems evident, that men are carried, by a natural 
 instinct or prepossession, to repose faith in their 
 senses ; and that, without any reasoning, or even al- 
 most before the use of reason, iwe always suppose an 
 external universe, which depends not on our percep- 
 , 1 tion, but would exist, though we and every sensible 
 
 I 
 
HUMAN' UNDERSTANDING, i6i 
 
 creature were absent or annihilated. Even the animal 
 creation are governed by a like opinion, and preserve 
 this belief of external objects, in all their thoughts, 
 designs, and actions. 
 
 It seems also evident, that, when men follow this 
 blind and powerful instinct of nature, they always 
 suppose the very images, presented by the senses, to 
 be the external objects, and never entertain any sus- 
 picion, that the one are nothing but representations of 
 the other. This very table, which we see white, and 
 f^hich we feel hard, is believed to exist, independent 
 of our perception, and to be something external to our 
 mind, which perceives it. Our presence bestows not 
 being on it : our absence does not annihilate it. It 
 preserves its existence uniform and entire, independ- 
 ent of the situation of intelligent beings, who perceive 
 or contemplate it. 
 
 But this universal and primary opinion of all men 
 is soon destroyed by the slightest philosophy, which 
 teaches us, that]'nothing can ever be present to the 
 mind but an image or perception] and that the senses 
 are only the inlets, through wliich these images are 
 conveyed, without being able to produce any immedi- 
 ate intercourse between the mind and the object. The 
 table, which we see, seems to diminish, as we remove 
 farther from it : but the real table, which exists inde- 
 pendent of us, suffers no alteration : it was, therefore, 
 nothing but its image, which was present to the mind. 
 These are the obvious dictates of reason; and no man, 
 who reflects, ever doubted, that the existences, which 
 we consider, when we say, this house and that treCy are 
 nothing but perceptions in the mind, and fleeting 
 copies or representations of other existences, which 
 remain uniform and independent. 
 
i6a AN ENQUIRY CONCERNING 
 
 So far, then, are we necessitated by reasoning to 
 contradict or depart from the primary instincts of na- 
 ture, and to embrace a new system with regard to the 
 evidence of our senses. But here philosophy finds 
 herself extremely embarrassed, when she would justify 
 this new system, and obviate the cavils and objections 
 of the sceptics. She can no longer plead the infallible 
 and irresistible Instinct of nature : for that led us to a 
 quite different system, which is acknowledged fallible 
 and even erroneous. And to justify this pretended 
 philosophical system, by a chain of clear and convin- 
 cing argument, or even any appearance of argument, 
 exceeds the power of all human capacity. 
 
 By what argument can it be proved, that the percep. 
 1 tlons of the mind must be caused by external obiects, 
 I entirely different from them, though resembling them 
 (if that be possible) and could not arise either from 
 the energy of the mind Itself, or from the suggestion 
 of some invisible and unknown spirit, or from some 
 other cause still more unknown to us? It is acknowl- 
 edged, that, in fact, many of these perceptions arise 
 not from anything external, as in dreams, madness, 
 and other diseases. And nothing can be more expli- 
 cable than the manner, in which body should so op- 
 erate upon mind as ever to convey an Image of itself 
 to a substance, supposed of so different, and even 
 contrary a nature. 
 
 It is a question of fact, whether the perceptions of 
 the senses be produced by external objects, resem- 
 I bling them : how shall this question be determined ? 
 By experience surely ; as all other questions of a like 
 nature. But here experience is, and must be entirely 
 silent. The mind has never anything present to it but 
 the perceptions, and cannot possibly reach any expe- 
 
HUMAN UNDERSTANDING. 163 
 
 ;/ 
 
 rience of their connexion with objects. The supposi- 
 tion of such a connexion is, therefore, without any, 
 foundation in reasoning. 
 
 To have recourse to the veracity of the supreme 
 Being, in order to prove the veracity of our senses, is 
 surely making a very unexpected circuit. If his vera- 
 city were at all concerned in this matter, our senses 
 would be entirely infallible; because it is not possible 
 that he can ever deceive. Not to mention, that, i|[Jhe 
 external world be once called in question, we shall be 
 ata loss to find arguments, by which we may prove 
 the existence of that Being or any of his attributes. 
 
 This is a topic, therefore, in which the profounder 
 and more philosophical sceptics will always triumph, 
 when they endeavour to introduce an universal doubt 
 into all subjects of human knowledge and enquiry. 
 Do you follow the instincts and propensities of nature, 
 may they say, in assenting to the veracity of sense ? 
 But these lead you to believe that the very perception 
 or sensible image is the external object. Do you dis- 
 claim this principle, in order to embrace a more ra- 
 tional opinion, that the perceptions are only represen 
 tations of something external? You here depart from 
 your natural propensities and more obvious sentiments; 
 and yet are not able to satisfy your reason, which can 
 never find any convincing argument from experience 
 to prove, that the perceptions are connected with any ] 
 external objects. -^ 
 
 There is another sceptical topic of a like nature, 
 derived from the most profound philosophy; which 
 might merit our attention, were it requisite to dive so 
 deep, in order to discover arguments and reasonings, 
 which can so little serve to any serious purpose. It 
 is universally allowed by modern enquirers, that aW 
 
JJ^ 
 
 V"" 
 
 164 AN- ENQUIRY CONCERNING 
 
 the sensible qualities of objects, such as hard, soft, hot, 
 cold, white, black, &c. are merely secondary, and exist 
 not in the objects themselves, but are perceptions of 
 the mind, without any external archetype or model, 
 which they represent. If this be allowed, with regard 
 to secondary qualities, it must also follow, with regard 
 to the supposed primary qualities of extension and 
 solidity; nor can the latter be any more entitled to 
 that denomination than the former. The idea of ex- 
 tension is entirely acquired from the senses of sight 
 and feeling ; and if all the qualities, perceived by tne 
 senses, be in the mind, not in the object, the same 
 conclusion must reach the idea of extension, which is 
 wholly dependent on the sensible ideas or the ideas 
 of secondary qualities. Nothing can save us from this 
 conclusion, but the asserting, that the ideas of those 
 primary qualities are attained by Abstraction^ an opin- 
 ion, which, if we examine it accurately, we shall find 
 to be unintelligible, and even absurd. An extension, 
 that is neither tangible nor visible, cannot possibly be 
 conceived : and a tangible or visible extension, which 
 is neither hard nor soft, black or white, isjequally be- 
 yond the reach of human conception. /Let any man 
 try to conceive a triangle in general, which is neither 
 Isosceles nor Scalenum, nor has any particular length 
 or proportion of sides ; and he will soon perceive the 
 absurdity of all the scholastic notions with regard to 
 abstraction and general ideas. ^ 
 
 IThis argument is drawn from Dr. Berkeley; and indeed most of the 
 writings of that very ingenious author form the best lessons of scepticism, 
 which are to be found either among the ancient or modern philosophers. 
 Bayle not excepted. He professes, however, in his title-page (and undoubt- 
 edly with great truth) to have composed his book against the sceptics as well 
 as against the atheists and free-thinkers. But that all his arguments, though 
 otherwise intended, are, in reality, merely sceptical, appears from this, that 
 they admit o/no answer and produce no conviction. Their only effect is to 
 
HUMAN UNDERSTANDING. 165 
 
 Thus the first philosophical objection to the evi- 
 dence of sense or to the opinion of external existence v,j 
 consists in this, that such an opinion, if rested on nat- 
 ural instinct, is contrary to reason, and if referred to 
 reason, is contrary to natural instinct, and at the same 
 time carries no rational evidence with it, to convince 
 an impartial enquirer. The second objection goes 
 farther, and represents this opinion as contrary to 
 reason : at least, if it be a principle of reason, that all 
 sensible qualities are in the mind, not in the object. 
 Bereave matter of all its intelligible qualities, both 
 primary and secondary, you in a manner annihilate , 
 it, and leave only a certain unknown, inexplicable i 
 something, as the cause of our perceptions ; a notion j 
 so imperfect, that no sceptic will think it worth while 
 to contend against it. 
 
 . . • \ 
 
 Part II. 
 
 It may seem a very extravagant attempt of the 
 sceptics to destroy reason by argument and ratiocina- 
 tion ; yet is this the grand scope of all their enquiries 
 and disputes. They endeavour to find objections, 
 both to our abstract reasonings, and to those which 
 regard matter of fact and existence. 
 
 The chief objection against all abstract reasonings 
 is derived from the ideas of space and time ; ideas, 
 which, in common life and to a careless view, are very 
 clear and intelligible, but when they pass through the 
 scrutiny of the profound sciences (and they are the 
 chief object of these sciences) afford principles, which 
 seem full of absurdity and contradiction. No priestly 
 
 cause that momentary amazement and irresolution and confusion, which is 
 the result of scepticism. 
 
i66 AN ENQUIRY CONCERNING 
 
 dogmas^ invented on purpose to tame and subdue the 
 rebellious reason of mankind, ever shocked common 
 sense more than the doctrine of the infinite divisibil- 
 ity of extension, with its consequences; as they are 
 pompously displayed by all geometricians and meta- 
 physicians, with a kind of triumph and exultation. A 
 real quantity, infinitely less than any finite quantity, 
 containing quantities infinitely less than itself, and so 
 on in infinitum ; this is an edifice so bold and prodig- 
 ious, that it is too weighty for any pretended demon- 
 stration to support, because it shocks the clearest and 
 most natural principles of human reason.^ But what 
 renders the matter more extraordinary, is, that these 
 seemingly absurd opinions are supported by a chain 
 of reasoning, the clearest and most natural; nor is it 
 possible for us to allow the premises without admit- 
 ting the consequences. Nothing can be more convin- 
 cing and satisfactory than all the conclusions concern- 
 ing the properties of circles and triangles ; and yet» 
 when these are once received, how can we deny, that 
 the angle of contact between a circle and its tangent 
 is infinitely less than any rectilineal angle, that as you 
 may increase the diameter of the circle in infinitum^ 
 this angle of contact becomes still less, even in infini- 
 tum, and that the angle of contact between other curves 
 and their tangents may be infinitely less than those 
 between any circle and its tangent, and so on, in infi- 
 
 1 Whatever disputes there may be about mathematical points^-'we must 
 allow that there are physical points; that is, parts of extension, which cannot 
 be divided or lessened, either by the eye or imagination. ' These images, 
 then, which are present to the fancy or senses, are absolutely indivisible, and 
 consequently must be allowed by mathematicians to be infinitely less than 
 any real part of extension ; and yet nothing appears more certain to reason, 
 than that an infinite number of them composes an infinite extension. How 
 much more an infinite number of those infinitely small parts of extension* 
 which are still supposed infinitely divisible. - 
 
HUMAN UNDERSTANDING, 167 
 
 nitum ? The demonstration of these principles seems 
 as unexceptionable as that which proves the three 
 angles of a triangle to be equal to two right ones, 
 though the latter opinion be natural and easy, and the 
 former big with contradiction and absurdity. Reason 
 here seems to be thrown into a kind of amazement and 
 suspence, which, without the suggestions of any scep- 
 tic, gives her a diffidence of herself, and of the ground 
 on which she treads. She sees a full light, which illu- 
 minates certain places ; but that light borders upon 
 the most profound darkness. And between these she 
 is so dazzled and confounded, that she scarcely can 
 pronounce with certainty and assurance concerning 
 any one object. 
 
 The absurdity of these bold determinations of the 
 abstract sciences seems to become, if possible, still 
 more palpable with regard to time than extension. 
 An infinite number of real parts of time, passing in 
 succession, and exhausted one after another, appears 
 so evident a contradiction, that no man, one should 
 think, whose judgement is not corrupted, instead of 
 being improved, by the sciences, would ever be able 
 to admit of it. 
 
 Yet still reason must remain restless, and unquiet, 
 even with regard to that scepticism, to which she is 
 driven by these seeming absurdities and contradic- 
 tions. How any clear, distinct idea can contain cir- 
 cumstances, contradictory to itself, or to any other 
 clear, distinct idea, is absolutely incomprehensible; 
 and is, perhaps, as absurd as any proposition, which 
 can be formed. So that nothing can be more scep- 
 tical, or more full of doubt and hesitation, than this 
 scepticism itself, which arises *rom some of the par- 
 
i 
 
 z68 AN ENQUIRY CONCERNING 
 
 adoxicai conclusions of geometry or the science of 
 quantity.^ 
 
 The sceptical objections to moral evidence, or to 
 the reasonings concerning matter of fact, are either 
 popular or philosophical The popular objections are 
 derived from the natural weakness of human under- 
 standing; the contradictory opinions, which have been 
 entertained in different ages and nations ; the varia- 
 tions of our judgement in sickness and health, youth 
 and old age, prosperity and adversity ; the perpetual 
 contradiction of each particular man's opinions and 
 sentiments ; with many other topics of that kind. It 
 is needless to insist farther on this head. These objec- 
 tions are but weak. For as, in common life, we rea- 
 son every moment concerning fact and existence, and 
 cannot possibly subsist, without continually employing 
 this species of argument, any popular objections, de- 
 rived from thence, must be insufficient to destroy that 
 evidence. The great subverter of Pyrrhonism or the 
 excessive principles of scepticism is action, and em- 
 ployment, and the occupations of common life. These 
 
 v^ 1 It seems to me not impossible to avoid these absurdities and contradic- 
 tions, if it be admitted, that there is no such thing as abstract or general 
 ideas, properly speaking; but that all general ideas are, in reality, particular- 
 ones, attached to a general term, which recalls, upon occasion, other partic- 
 ular ones, that resemble, in certain circumstances, the idea, present to the 
 mind. Thus when the term Horse is pronounced, we immediately figure to 
 ourselves the idea of a black or a white animal, of a particular size or figure: 
 But as that term is also usually applied to animals of other colours, figures 
 and sizes, these ideas, though not actually present to the imagination, are 
 easily recalled; and our reasoning and conclusion proceed in the same way, 
 as if they were actually present. If this be admitted (as seems reasonable) 
 it follows that all the ideas of quantity, upon which mathematicians reason, 
 are nothing but particular, and such as are suggested by the senses and im- 
 agination, and consequently, cannot be infinitely divisible. It is sufi5cient to 
 have dropped this hint at present, without prosecuting it any farther. It cer 
 tainly concerns all lovers of science not to expose themselves to the ridicule 
 and contempt of the ignorant by their conclusions ; and this seems the readi- 
 est solution of these difficulties. 
 
HUMAN UNDERSTANDING. 169 
 
 principles may flourish and triumph in the schools ; 
 where it is, indeed, difficult, if not impossible, to re- 
 fute them. But as soon as they leave the shade, and 
 by the presence of the real objects, which actuate our 
 passions and sentiments, are put in opposition to the 
 more powerful principles of our nature, they vanish] 
 like smoke, and leave the most determined sceptic inj 
 the same condition as other mortals. 
 
 The sceptic, therefore, had better keep within his 
 proper sphere, and display those philosophical objec- 
 tions, which arise from more profound researches. 
 Here he seems to have ample matter of triumph; 
 while he justly insists, that all our evidence for any 
 matter of fact, which lies beyond the testimony of 
 sense or memory, is derived entirely from the relation 
 of cause and effect ; that we have no other idea of this 
 relation than that of two objects, which have been 
 frequently conjoined together ; that we have no argu- 
 ment to convince us, that objects, which have, in our 
 experience, been frequently conjoined, will likewise, 
 in other instances, be conjoined in the same manner ; 
 and that nothing leads us to this inference but custom 
 or a certain instinct of our nature ; which it is indeed 
 difficult to resist, but which, like other instincts, may j 
 be fallacious and deceitful. While the sceptic insists 
 upon these topics, he shows his force, or rather, in- 
 deed, his own and our weakness ; and seems, for the 
 time at least, to destroy all assurance and conviction. 
 These arguments might be displayed at greater length 
 if any durable good or benefit to society could ever 
 be expected to result from them. 
 
 For here is the chief and most confounding objec- [ 
 tion to excessive scepticism, that no durable good can I 
 ever result from it ; while it remains in its full force I 
 
 ;/ 
 
 rl 
 
I70 AN ENQ UIR Y CONCERNING 
 
 and vigour. We need only ask such a sceptic, What 
 his meaning is? And what he proposes by all these curious 
 researches ? He is immediately at a loss, and knows 
 not what to answer. A Copernican or Ptolemaic, who 
 supports each his different system of astronomy, may 
 hope to produce a conviction, which will remain con- 
 stant and durable, with his audience. A Stoic or 
 Epicurean displays principles, which may not be dur- 
 able, but which have an effect on conduct and beha- 
 Iviour. But a Pyrrhonian cannot expect, that his phi- 
 losophy will have any constant influence on the mind : 
 ©r if it had, that its influence would be beneficial to 
 I Society. On the contrary, he must acknowledge, if he 
 jwill acknowledge anything, that all human life must 
 Iperish, were his principles universally and steadily to 
 jprevail. All discourse, all action would immediately 
 Icease ; and men remain in a total lethargy, till the 
 •necessities of nature, unsatisfied, put an end to their 
 miserable existence. It is true ; so fatal an event is 
 very little to be dreaded. Nature is always too strong 
 for principle. And though a Pyrrhonian may throw 
 II himself or others into a momentary amazement and 
 \ confusion by his profound reasonings; the first and 
 most trival event in life will put to flight all his doubts 
 and scruples, and leave him the same, in every point 
 of action and speculation, with the philosophers of 
 every other sect, or with those who never concerned 
 I themselves in any philosophical researches. When he 
 I awakes from his dream, he will be the first to join in 
 the laugh against himself, and to confess, that all his 
 , objections are mere amusement, and can have no 
 [ other tendency than to show the whimsical condition 
 
 I of mankind, who must act and reason and believe ; 
 though they are not able, by their most diligent en- 
 
HUMAN UNDERSTANDING. 171 
 
 quiry, to satisfy themselves concerning the foundation / 
 of these operations, or to remove the objections, which* 
 may be raised against them. 
 
 Part III. 
 
 There is, indeed, a more mitigated scepticism or 
 academical philosophy, which may be both durable 
 and useful, and which may, in part, be the result of 
 this Pyrrhonism, or excessive scepticism, when its un- 
 distinguished doubts are, in some measure, corrected 
 by common sense and reflection. The greater part of 
 mankind are naturally apt to be affirmative and dog- 
 matical in their opinions ; and while they see objects 
 only on one side, and have no idea of any counterpois- 
 ing argument, they throw themselves precipitately 
 into the principles, to which they are inclined ; nor 
 have they any indulgence for those who entertain op- 
 posite sentiments. To hesitate or balance perplexes 
 their understanding, checks their passion, and sus- 
 pends their action. They are, therefore, impatient 
 till they escape from a state, which to them is so un- 
 easy : and they think, that they could never remove 
 themselves far enough from it, by the violence of their 
 affirmations and obstinacy of their belief. But could 
 such dogmatical reasoners become sensible of the 
 strange infirmities of human understanding, even in 
 its most perfect state, and when most accurate and 
 cautious in its determinations; such a reflection would 
 naturally inspire them with more modesty and reserve, 
 and diminish their fond opinion of themselves, and 
 their prejudice against antagonists. The illiterate 
 may reflect on the disposition of the learned, who, 
 amidst all the advantages of study and reflection, are 
 
\ 
 
 172 A AT ENQ UIR Y CONCERNING 
 
 commonly still diffident In their determinations : and 
 if any of the learned be inclined, from their natural 
 temper, to haughtiness and obstinacy, a small tincture 
 of Pyrrhonism might abate their pride, by showing 
 them, that the few advantages, which they may have 
 attained over their fellows, are but inconsiderable, if 
 compared with the universal perplexity and confusion, 
 which is inherent in human nature. In general, there 
 is a degree of doubt, and caution, and modesty, which, 
 in all kinds of scrutiny and decision, ought for ever 
 to accompany a just reasoner. 
 
 Another species of mitigated scepticism which may 
 be of advantage to mankind, and which may be the 
 natural result of the Pyrrhonian doubts and scruples, 
 is the limitation of our enquiries to such subjects as 
 are best adapted to the narrow capacity of human 
 understanding. The imagination of man is naturally 
 sublime, delighted with whatever is remote and extra- 
 ordinary, and running, without control, into the most 
 distant parts of space and time in order to avoid the 
 objects, which custom has rendered too familiar to it. 
 A correct judgement observes a contrary method, and 
 avoiding all distant and high enquiries, confines itself 
 to common life, and to such subjects as fall under 
 daily practice and experience ; leaving the more sub- 
 lime topics to the embellishment of poets and orators, 
 or to the arts of priests and politicians. To bring us 
 to so salutary a determination, nothing can be more 
 serviceable, than to be once thoroughly convinced of 
 the force of the Pyrrhonian doubt, and of the impos- 
 sibility, that anything, but the strong power of natural 
 instinct, could free us from it. Those who have a 
 propensity to philosophy, will still continue their re- 
 searches; because they reflect, that, besides the im- 
 
HUMAN UNDERSTANDING. 173 
 
 mediate pleasure, attending such an occupation, phil- 
 osophical decisions are nothing but the reflections of 
 common life, methodized and corrected. But they 
 will never be tempted to go beyond common life, so 
 long as they consider the imperfection of those facul- 
 ties which they employ, their narrow reach, and their 
 inaccurate operations. While we cannot give a satis- 
 factory reason, why we believe, after a thousand expe- 
 riments, that a stone will fall, or fire burn; can we 
 ever satisfy ourselves concerning any determination, 
 which we may form, with regard to the origin of worlds, 
 and the situation of nature, from, and to eternity ? 
 
 This narrow limitation, indeed, of our enquiries, 
 is, in every respect, so reasonable^ithat it suffices to 
 make the slightest examination into the natural pow- 
 ers of the human mind and to compare them with 
 their objects, in order to recommend it to us. We 
 shall then find what are the proper subjects of science 
 and enquiry. 
 
 It seems to me, that the only objects of the abstract 
 science or of demonstration are quantity and number, 
 and that all attempts to extend this more perfect spe- 
 cies of knowledge beyond these bounds are mere soph- 
 istry and illusion. As the component parts of quantity 
 and number aire'entirely similar, their relations become 
 intricate and involved; and nothing can be more cu- 
 rious, as well as useful, than to trace, by a variety of 
 mediums their equality or inequality, through their 
 different appearances. But as all other ideas are 
 clearly distinct and different from each other, we can 
 never advance farther, by our utmost scrutiny, than 
 to" observe this diversity, and, by an obvious reflection, 
 pronounce one thing not to be another. Or if there 
 be any difficulty in these decisions, it proceeds entirely 
 
 I 
 
174 AN ENQUIRY CONCERNING 
 
 from the undeterminate meaning of words, which is 
 corrected by juster definitions. That the square of the 
 hypothenuse is equal to the squares of the other two sides, 
 cannot be known, let the terms be ever so exactly de- 
 fined, without a train of reasoning and enquiry. But 
 to convince us of this proposition, that where there is 
 no property, there can be no injustice, it is only necessary 
 to define the terms, and explain injustice to be a vio- 
 lation of property. This proposition is, indeed, noth- 
 ing but a more imperfect definition. It is the same 
 case with all those pretended syllogistical reasonings, 
 ^hich may be found in every other branch of learning, 
 except the sciences of quantity and number; and these 
 may safely, I think, be pronounced the only proper 
 objects of knowledge and demonstration. 
 
 All other enquiries of men regard only matter of 
 fact and existence ; and these are evidently incapable 
 of demonstration. Whatever is may not be. No nega- 
 tion of a fact can involve a contradiction. The non- 
 existence of any being, without exception, is as clear 
 and distinct an idea as its existence. The proposition, 
 which affirms it not to be, however false, is no less 
 conceivable and intelligible, than that which affirms it 
 to be. The case is different with the sciences, properly 
 so called. Every proposition, which is not true, is 
 there confused and unintelligible. That the cube root 
 of 64 is equal to the half of 10, is a false proposition, 
 and can never be distinctly conceived. But that Cae- 
 sar, or the angel Gabriel, or any being never existed, 
 may be a false proposition, but still is perfectly con- 
 ceivable, and implies no contradiction. 
 
 The existence, therefore, of any being can only be 
 proved by arguments from its cause or its effect ; and 
 these arguments are founded entirely on experience. 
 
HUMAN UNDERSTANDING. 175 
 
 If we reason a priori, anything may appear able to 
 produce anything. The falling of a pebble may, for 
 aught we know, extinguish the sun; or the wish of a 
 man control the planets in their orbits. It is only ex-\ 
 perience, which teaches us the nature and bounds of 
 cause and effect, and enables us to infer the existence 
 of one object from that of another.^ Such is the foun- 
 dation of moral reasoning, which forms the greater 
 part of human knowledge, and is the source of all 
 human action and behaviour. 
 
 Moral reasonings are either concerning particular or 
 general facts. All deliberations in life regard the for- 
 mer ; as also all disquisitions in history, chronology, 
 geography, and astronomy. 
 
 The sciences, which treat of general facts, are pol- 
 itics, natural philosophy, physic, chemistry, &c. where 
 the qualities, causes and effects of a whole species of 
 objects are enquired into. 
 
 Divinity or Theology, as It proves the existence of 
 a i^eity, and the immortality of souls, is composed 
 partly of reasonings concerning particular, partly con- 
 cerning general factSo It has a foundation in reason, 
 so far as it is supported by experience. But its best 
 and most solid foundation is faith and divine reve 
 lation. 
 
 Morals and criticism are not so properly objects of 
 the understanding as of taste and sentiment. Beauty, 
 whether moral or natural, is felt, more properly than 
 perceived. Or if we reason concerning it, and endeav- 
 our to fix its standard, we regard a new fact, to wit, 
 
 i That impious maxim of tha ancient philosophy, Ex niktlo, nihil fit, by 
 which the creation of matter was excluded, ceases to be a maxim; according 
 to this philosophy. Not only the wiH of the supreme Being may create mat- 
 ter; but, for aught we know a priori, the will of any other being might create 
 it, or any other cause, that the most whimsical imagination can assign. 
 
176 AN ENQUIRY CONCERNING 
 
 the general tastes of mankind, or some such fact, 
 which may be the object of reasoning and enquiry. 
 
 When we run over libraries, persuaded of these 
 principles, what havoc must we make ? If we take in 
 our hand any volume; of divinity or school metaphys- 
 ics, for instance; let us ^iSY^Does it contain any abstract 
 reasoning concerning quantity or number ? No. Does it 
 \ ''contain any experimental reasoning concerning matter of 
 fact and existence ? No. Commit it then to the flames;^ 
 for it can contain nothing but sophistry and illusion. 
 
SELECTIONS FROM 
 A TREA TISE OF HUMAN NA TUBE 
 
 BOOK I, 
 BY DAVID HUME 
 
A 
 
 TREATISE 
 
 O F 
 
 Human Nature: 
 
 BEING 
 
 An Attempt to introduce the ex- 
 perimental Method of Reafoning 
 
 I NTO 
 
 MORAL SUBJECTS. 
 
 Rara temporumfelicitas^ ubi /entire^ qucB velis; & qucB 
 fen ias^ dicere licet. Tacit, 
 
 Book L 
 
 OF THE 
 UNDERSTANDING. 
 
 LONDON: 
 
 Printed for John Noon, at the White-Hart, near 
 
 Mercer's- Chapel \w Cheapfide. 
 
 MDCCXXXIX. 
 
The Contents of 
 A Treatise of Human Nature 
 
 BOOK I. 
 
 Or THE UXDERSTANDINO. 
 PART I. 
 
 Of ideas; their origin^ composition^ abstraction connexion^ ^c. 
 
 SECT, PAGE 
 
 I. Of the origin of our ideas 
 II. Division of the subject .... 
 III. Of the ideas of the memory and imagination 
 
 IV. Of the connexion or association of ideas 
 V. Of relations ..... 
 VI. Of modes and substances 
 VII. Of abstract ideas . . . . , 
 
 227 
 
 PART II. 
 
 Of the ideas of space and time. 
 I. Of the infinite divisibility of our ideas of space 
 and time ........ 
 
 II. Of the infinite divisibility of space and time . 
 
 III. Of the other qualities of our ideas of space and time 
 
 IV. Objections answer'd ...... 
 
 V. The same subject continu'd 
 
 VI. Of the idea of existence and of external existence . 229 
 
 PART III. 
 Of knowledge and probability, 
 
 I. Of knowledge 185 
 
 II. Of probability; and of the idea of cause and effect . 190 
 III. Why a cause is always necessary? .... 197 
 
 * Only the sections thus indicated are here reproduced. 
 
l82 
 
 CONTENTS. 
 
 SECT. 
 
 IV. Of the component parts of our reasonings concerning 
 causes and effects ..... 
 V. Of the impressions of the senses and memory . 
 VI. Of the inference from the impression to the idea 
 VII. Of the nature of the idea, or belief 
 VIII. Of the causes of behef ..... 
 IX. Of the effects of other relations, and other habits 
 X. Of the influence of belief .... 
 XI. Of the probability of chances . . • 
 
 XII. Of the probability of causes .... 
 XIII. Of unphilosophical probability 
 *XIV. Of the idea of necessary connexion 
 
 XV. Rules by which to judge of causes and effects 
 XVI. Of the reason of animals .... 
 
 202 
 
 PART IV. 
 
 Of the sceptical and other systems of philosophy 
 I. Of scepticism with regard to reason 
 II. Of scepticism with regard to the senses 
 
 III. Of the antient philosophy 
 
 IV. Of the modern philosophy 
 V. Of the immateriality of the soul 
 
 VI. Of personal identity 
 VII. Conclusion of this book 
 
 Appendix .... 
 
 232 
 
 245 
 260 
 
 * Only the sections thus indicated are here reproduced. 
 
THE DOCTRINE OF CAUSALITY 
 
 SELECTIONS FROM 
 BOOK /., PART III. 
 
BOOK I. 
 
 PART III. 
 
 OF KNOWLEDGE AND PROBABILITY. 
 
 Section I. 
 
 Of knowledge. 
 
 There are^ seven different kinds of philosophical 
 relation, vis. resemblance, identity, relations of time 
 and place, proportion in quantity or number, degrees 
 in any quality, contrariety, and causation. These re- 
 lations may be divided into two classes; into such as] 
 depend entirely on the ideas, which we compare to- 
 gether, and such as may be changed without any 
 change in the ideas. 'Tis from the idea of a triangle,^ 
 that we discover the relation of equality, which its 
 three angles bear to two right ones ; and this relation 
 is invariable, as long as our idea remains the same. 
 On the^ntrary;, the relations of contiguity and dis- 
 iance betwixt two objects may be chang'd merely by 
 an alteration of their place, without any change on the 
 objects"^ themselves or on their ideas; and the place 
 depends on a hundred different accidents, which can- 
 not be foreseen by the mind. 'Tis the same case with 
 identity and causation. Two objects, tho' perfectly re- 
 sembling each other, and even appearing in the same 
 place at different times, may be numerically different: 
 And as the power, by which one object produces an 
 other, is never discoverable merely from their id 
 
 1 Part I., Sect V. 
 
-f- 
 
 i86 A TREATISE OF HUMAN NATURE PART III 
 
 I 'tis evident cause and effect are relations, of which we 
 receive information from experience, and not from any 
 abstract reasoning or reflexion. There is no single 
 phaenomenon, even the most simple, which can be 
 accounted for from the qualities of the objects, as they 
 appear to us; or which we cou'd foresee without the 
 help of our memory and experience. 
 
 It appears, therefore, that of these seven philo- 
 sophical relations, there remain only four, which de- 
 pending solely upon ideas, can be the objects of knowl- 
 edge and certainty. These four are resemblance, con- 
 trariety, degrees in quality, and proportions in quan- 
 tity or number. Three of these relations are discover- 
 able at first sight, and fall more properly under the 
 province of intuition than demonstration. When any 
 objects resemble each other, the resemblance will at 
 first strike the eye, or rather the mind; and seldom 
 requires a second examination. The case is the same 
 with contrariety, and with the degrees of any quality. 
 No one can once doubt but existence and non-existence 
 destroy each other, and are perfectly incompatible and 
 contrary. And tho' it be impossible to judge exactly 
 of the degrees of any quality, such as colour, taste, 
 heat, cold, when the difference betwixt them is very 
 small ; yet 'tis easy to decide, that any of them is supe- 
 rior or inferior to another, when their difference is 
 considerable. And this decision we always pronounce 
 at first sight, without any enquiry or reasoning. 
 
 We might proceed, after the same manner, in fixing 
 the proportions of quantity or number, and might at 
 one view observe a superiority or inferiority betwixt 
 any numbers, or figures; especially where the differ- 
 ence is very great-and remarkable. As to equality or 
 any exact proportion, we can only guess at it from a 
 
SECT. I BOOK I. OF THE UNDERSTANDING 187 
 
 single consideration ; except in very short numbers, or 
 very limited portions of extension; which are com- 
 prehended in an instant, and where we perceive an 
 impossibility of falling into any considerable error. 
 In all other cases we must settle the proportions with 
 some liberty, or proceed in a more artificial manner. 
 
 I have already observed, that geometry, or the art, 
 by which we fix the proportions of figures; tho' it 
 much excels, both in universality and exactness, the 
 loose judgments of the senses and imagination; yet 
 never attains a perfect precision and exactness. Its 
 first principles are still drawn from the general appear- 
 ance of the objects ; and that appearance can never af- 
 ford us any security, when we examine the prodigious 
 minuteness of which nature is susceptible. Our ideas 
 seem to give a perfect assurance, that no two right 
 lines can have a common segment; but if we consider 
 these ideas, v/e shall find, that they always suppose a 
 sensible inclination of the two lines, and that where 
 the angle they form is extremely small, we have no 
 standard of a right line so precise, as to assure us of 
 the truth of this proposition. Tis the same case with 
 most of the primary decisions of the mathematics. 
 
 There remain, therefore, algebra and arithemetic 
 as the only sciences, in which we can carry on a chain 
 of reasoning to any degree of intricacy, and yet pre- 
 serve a perfect exactness and certainty. We are pos- 
 sest of a precise standard, by which we can judge of 
 the equality and proportion of numbers ; and according 
 as they correspond or not to that standard, we deter- 
 mine their relations, without any possibility of error. 
 When two numbers are so combined, as that the one 
 has always an unite answering to every unite of the 
 other, we pronounce them equal ; and 'tis for want of 
 
l88 A TREATISE OF HUMAN NATURE PART III 
 
 such a standard of equality in extension, that geometry 
 can scarce be esteem'd a perfect and infallible science. 
 
 But here it may not be amiss to obviate a difficulty, 
 which may arise from my asserting, that tho' geometry 
 falls short of that perfect precision and certainty, 
 which are peculiar to arithmetic and algebra, yet it 
 excels the imperfect judgments of our senses and 
 imagination. The reason why I impute any defect 
 to geometry, is, because its original and fundamental 
 principles are deriv'd merely from appearances ; and it 
 may perhaps be imagin'd, that this defect must always 
 attend it, and keep it from ever reaching a greater 
 exactness in the comparison of objects or ideas, than 
 what our eye or imagination alone is able to attain. 
 I own that this defect so far attends it, as to keep it 
 from ever aspiring to a full certainty : But since these 
 fundamental principles depend on the easiest and least 
 deceitful appearances, they bestow on their conse- 
 quences a degree of exactness, of which these conse- 
 quences are singly incapable. 'Tis impossible for the 
 eye to determine the angles of a chiliagon to be equal 
 to 1996 right angles, or to make any conjecture, that 
 approaches this proportion; but when it determines, 
 that right lines cannot concur; that we cannot draw 
 more than one right line between two given points; 
 its mistakes can never be of any consequence. And 
 this is the nature and use of geometry, to run us up to 
 such appearances, as, by reason of their simplicity, 
 cannot lead us into any considerable error. 
 
 I shall here take occasion to propose a second 
 observation concerning our demonstrative reasonings, 
 which is suggested by the same subject of the mathe- 
 matics. 'Tis usual with mathematicians, to pretend, 
 that those ideas, which are their objects, are of so 
 
SECT. I BOOK L OF THE UNDERSTANDING 189 
 
 refin'd and spiritual a nature, that they fall not under 
 the conception of the fancy, but must be comprehended 
 by a pure and intellectual view, of which the superior 
 faculties of the soul are alone capable. The same 
 notion runs thro' most parts of philosophy, and is prin- 
 cipally made use of to explain our abstract ideas, and 
 to shew how we can form an idea of a triangle, for 
 instance, which shall neither be an isosceles nor scale- 
 num, nor be confin'd to any particular length and 
 proportion of sides. Tis easy to see, why philosophers 
 are so fond of this notion of some spiritual and refin'd 
 perceptions ; since by that means they cover many of 
 their absurdities, and may refuse to submit to the de- 
 cisions of clear ideas, by appealing to such as are 
 obscure and uncertain. But to destroy this artifice, we 
 need but reflect on that principle so oft insisted on, 
 that all our ideas are copy'd from our impressions. 
 For from thence we may immediately conclude, that 
 since all impressions are clear and precise, the ideas, 
 which are copied from them, must be of the same 
 nature, and can never, but from our fault, contain any 
 thing so dark and intricate. An idea is by its very 
 nature weaker and fainter than an impression ; but 
 being in every other respect the same, cannot imply 
 any very great mystery. If its weakness render it 
 obscure, ' 'tis our business to remedy that defect, as 
 much as possible, by keeping the idea steady and pre- 
 cise; and till we have done so, 'tis in vain to pretend 
 to reasoning and philosophy. 
 
Section II. 
 Of probability; and of the idea of cause and effect. 
 
 This is all I think necessary to observe concerning 
 those four relations, which are the foundation of 
 science; but as to the other three, which depend not 
 upon the idea, and may be absent or present even while 
 that remains the same, 'twill be proper to explain 
 them more particularly. These three relations are 
 identity, the situations in time and place, and causa- 
 tion. 
 
 All kinds of reasoning consist in nothing but a 
 c ompar ison, and a discovery of those relations, either 
 constant or inconstant, which two or more objects 
 bear to each other. This comparison we may make, 
 either when both the objects are present to the senses, 
 or when neither of them is present, or when only one. 
 When both the objects are present to the senses along 
 with the relation, we call this perception rather than 
 reasoning; nor is there in this case any exercise of the 
 thought, or any action, properly speaking, but a mere 
 passive admission of the impressions thro' the organs 
 of sensation. According to this way of thinking, we 
 ^}^h^ B9^^9 r^^^iv^ ^s reasoning any of the observa- 
 tions we may make concerning identity, and the rela- 
 tions of time and place; since in none of them the mind 
 can go beyond what is immediately present to the 
 senses, either to discover the real existence or the 
 relations of objects. 'Tis only causation, which pro- 
 duces such a conn^ion, as to give us assurance from 
 
SECT. II BOOK L OF THE UNDERSTANDING 191 
 
 t he existence or action of one object, that 'twas fol- 
 low'd or preceded by any other existence or action; 
 nor can the other two relations be ever made use of 
 in reasoning, except so far as they either affect or are 
 affected by it. There is nothing in any objects to per- 
 swade us, that they are either always remote or always 
 contiguous; and when from experience and observa- 
 tion we discover, that their rela^tt^in this particular 
 is invariable, we always conclu^^^M'e is some secret 
 cause, which separates or unites^^K The same rea- 
 soning extends to identity. We^Hdily suppose an 
 object may continue individually tl^fcne, tho' several 
 times absent from and present t^Ke senses; and 
 ascribe to it an identity, notwithsSnaing the inter- 
 ruption of the perception, whenever we conclude, that 
 if we had kept our eye or hand constantly upon it, it 
 wou'd have convey'd an invariable and uninterrupted 
 perception. But this conclusion beyond the impres 
 sions of our senses can be founded only on the con- 
 nexion of cause and eifect; nor can we otherwise have 
 any security, that the object is not chang'd upon us, 
 however much the new object may resemble that which 
 was formerly present to the senses. Whenever we 
 discover such a perfect resemblance, we consider, 
 whether it be common in that species of objects; 
 whether possibly or probably any cause cou'd operate 
 in producing the change and resemblance ; and accord- 
 ing as we determine concerning these causes and 
 effects, we form our judgment concerning the identity 
 of the object. 
 
 Here then it appears, that of those three relations, 
 which depend n^Tupon the mere ideas, the only one, 
 that can be trac'd beyond our senses, and informs us 
 of existences and objects, which we do not see or„feel, 
 
/ 
 
 192 A TREATISE OF HUMAN NATURE FART III 
 
 is^ causatio n. This relation, therefore, we shall en- 
 deavour to explain fully before we leave the subject of 
 the understanding. 
 
 To begin regularly, we must consider the idea of 
 causation, and see from what origin it is deriv'd. 'Tis 
 impossible to reason justly, without understanding per- 
 fectly the idea concerning which we reason; and 'tis 
 impossible perfec^^p understand any idea, without 
 tracing it up to i^^Hfin, and examining that primary 
 impression, from^^Kn it arises. The examination of 
 the impression t^Bws a clearness on the idea; and 
 the examinatioi^^Pthe idea bestows a like clearness 
 on all our reas^Kg. 
 
 Let us thereiSe cast our eye on any two objects, 
 which we call cause and effect, and turn them on all 
 sides, in order to find that impression, which produces 
 an idea of such prodigious consequence. At first sight 
 1 perceive, that I m ust not search f or it in any o^ the 
 particular q iialit ies of the objects; since, which-ever of 
 these qualities I pitch on, I find some object, that is not 
 possest of it, and yet falls under the denomination of 
 cause or effect. And indeed there is nothing existent, 
 either externally or internally, which is not to be con- 
 sider'd either as a cause or an effect; tho' 'tis plain 
 there is no one quality, which universally belongs to 
 all beings, and gives them a title to that denomination. 
 
 The idea, then, of causation must be deriv'd from 
 some relation among objects; and that relation we 
 must now endeavour to discover. I find in the first 
 place, that whatever objects are consider 'd as causes 
 or effects, are contiguous ; and that nothing can oper- 
 ate in a time or place, which is ever so little remov'd 
 from those of its existence. Tho' distant objects may 
 sometimes seem productive of each other, they are 
 
SECT. II BOOK I. OF THE UNDERSTANDING 193 
 
 commonly found upon examination to be link'd by a 
 chain of causes, which are contiguous among them- 
 selves, and to the distant objects; and when in any 
 particular instance we cannot discover this connexion, 
 we still presume it to exist. We may therefore con- 
 sider the relation of contiguity as essential to that ^ 
 of causation; at least may suppose it such, according A 
 to the general opinion, till we can find a more^ proper 
 occasion to clear up this mattgjjjl^ examining what 
 objects are or are not susceptib^Hp juxtaposition and 
 conjunction. ,-;v 
 
 The second relation I shall observe as essential to 
 causes and effects, is not so universally acknowledg'd, ^^ 
 but is liable to some controversy. Tis that of priority [ ^ 
 of time in the cause before the effect. Some. pretend 
 that 'tis not absolutely necessary a cause shou'd pre- 
 cede its effect; but that any object or action, in the^* ^. 
 very first moment of its existence, may exert its pro- / ^ 
 ductive quality, and give rise to another object or 
 action, perfectly co-temporary with itself. But beside 
 that experience in most instances seems to contradict 
 this opinion, we may establish the relation of priority 
 by a kind of inference or reasoning. 'Tis an estab- 
 lish 'djrnaxim both in natural and moral philosophy, 
 that an object, which exists for any time in its full 
 perfection without producing another, is not its sole 
 cause; but is assisted by some other principle, which 
 pushes it from its state of inactivity, and makes it 
 exert that energy, of which it was secretly possest. 
 Now if any*°cause may be perfectly co-temporary with 
 its effect, 'tis certain, according to this maxim, that 
 they must all of them be so; since any one of them, 
 which retards its operation for a single moment, exerts 
 
 1 Part IV., Sect. V. 
 
 ,€^ 
 
194 ^ TREATISE OF HUMAN NATURE PART III 
 
 not itself at that very Individual time, in which it 
 might have operated ; and therefore is no proper cause. 
 The consequence of this wou'd be no less than the 
 destruction of that succession of causes, which we 
 observe in the world; and indeed, the utter annihila- 
 tion of time. For if one cause were co-temporary 
 with its effect, and this effect with its effect, and so 
 ^ on, 'tis plain there wou'd be no such thing as succes- 
 sion, and all objecjs must be co-existent. 
 
 If this argumem:- appear satisfactory, 'tis well. If 
 not, I beg the reader to allow me the same liberty, 
 which I have us'd in the preceding case, of supposing 
 it such. For he shall find, that the affair is of no great 
 importance. 
 
 Having thus discover'd or suppos'd the two rela- 
 tions of contigu ity and succession to be essential to 
 causes and effects, I find I am stopt short, and can 
 proceed no farther in considering any single instance 
 of cause and effect, potion in one body is regarded 
 upon impulse as the cause of motion in another. 
 When we consider these objects with the utmost atten- 
 tion, we find only that the one body approaches the 
 other; and that the motion of it precedes that of the 
 other, but without any sensible interval. 'Tis in vain 
 to rack ourselves with farther thought and reflexion 
 upon this subject. We can go no farther in consider- 
 ing this particular instance. 
 
 Shou'd any one leave this instance, and pretend to 
 define a cause, by saying it is something productive of 
 another, 'tis evident he wou'd say nothing. For what 
 does he mean by production f Can he give any defini- 
 tion of it, that will not be the same with tha* of 
 causation? If he can ; I desire it may be produc'd. If 
 
SECT, IJ BOOK I. OF THE UNDERSTANDING 195 
 
 he cannot ; he here runs in a circle, and gives a synon- 
 imous term instead of a definition. 
 
 Shall we then rest contented with these two rela- 
 tions of contiguity and succession, as affording a com- 
 pleat idea of causation? By no means, ^nobject y 
 mayLJae^contiguous and prior to another, without being 
 considered as its^cause. There is a necessary con- / 
 NEXiON to be taken into consideration; anJthat rela- j 
 tion is of much greater importance, than any of the 
 other two above-mention'd. 
 
 Here again I turn the object on all sides, in order 
 to discover the nature of this necessary connexion, and 
 find the impression, or impressions, from which its 
 idea may be deriv'd. When I cast my eye on the 
 k nown qualit ies of objects, I immediately discover that 
 the relation of cause and effect depends not in the 
 least on them. When I consider their relations, I can 
 find none but those of contiguity and succession ; which 
 I have already regarded as imperfect and unsatisfac- 
 tory. Shall the despair of success make me assert, 
 that I am here possest of an idea, which is not pre- 
 ceded by any similar impression? This wou'd be too 
 strong a proof of levity and inconstancy ; since the con- 
 trary principle has been already so firmly established, 
 as to admit of no farther doubt; at least, till we have 
 more fully examin'd the present difficulty. 
 
 We must, therefore, proceed like those, who being 
 in search of any thing that lies conceal'd from them, 
 and not finding it in the place they expected, beat about 
 all the neighbouring fields, without any certain view or 
 design, in hopes their good fortune will at last guide 
 them to what they search for. 'Tis necessary for us 
 to leave the direct survey of this question concerning 
 the nature of that necessary connexion, which enters 
 
196 A TREATISE OF HUMAN NATURE PART III 
 
 into our idea of cause and effect ; and endeavour to find 
 some other questions, the examination of which will 
 perhaps afford a hint, that may serve to clear up the 
 present difficulty. Of these questions there occur two, 
 which I shall proceed to examine, vis. 
 
 First, For what reason we pronounce it necessar y, 
 JK^ that every thing wKose existence has a beginning, 
 shou'd also have a cause? 
 
 Secondly, Why we conclude, that such particular 
 causes must necessarily have such particular effects; 
 and what is the nature of that inference we draw from 
 the one to the other, and of thehelief^we repose in it? 
 
 I shall only observe before I proceed any farther, 
 that tho' the ideas of cause and effect be deriv'd from 
 the impressions of reflexion as well as from those of 
 sensation, yet for brevity's sake, I commonly mention 
 only the latter as the origin of these ideas ; tho' I de- 
 sire that whatever I say of them may also extend to 
 the former. Passions are connected with their objects 
 and with one another; no less than external bodies are 
 connected together. The same relation, then, of cause 
 and effect, which belongs to one, must be common to 
 all of them. 
 
 V- 
 
Section III. 
 Why a cause is always necessary. 
 
 To begin with the first question concerning the 
 necessity of a cause: 'Tis a general maxim in philos- ** 
 ophy, that whatever begmsjo exist, must have a cause 
 of existence. This is commonly taken for granted in 
 alFreasonings, without any proof given or demanded. 
 'Tis suppos'd to be founded on intuition, and to be 
 one of those maxims, which tho' they may be deny'd 
 with the lips, 'tis impossible for men in their hearts 
 really to doubt of. But if we examine this maxim by. 
 the idea of knowledge above-explain'd, we shall dis- 
 cover in it no mark of . any such i ntuiti ve certainty ; 
 but on the contrary shall find, that^tis~o? a nature 
 quite foreign to that species of conviction. 
 
 All certainty arises from the comparison of ideas, 
 and from the discovery of such relations as are unal- 
 terable, so long as the ideas continue the same. These 
 relations are resemblance, ^proportions in quantity and t^^^^^ 
 number, degrees of any quality, and contrariety ; none ^V^^*^^: 
 of which are imply'd in this proposition, Whatever has 
 a beginning has also a cause of existence. That prop- 
 osition therefore is not intuitively certain. At least 
 any one, who wou'd assert it to be intuitively certain, 
 must deny these to be the only infallible relations, and 
 must find some other relation of that kind to be im- 
 ply'd in it; which it will then be time enough to 
 examine. 
 
y 
 
 198 A TREATISE OF HUMAN NATURE PART III 
 
 But here is an argument, which proves at once, 
 that the foregoing proposition is neither intuitively 
 nor demonstrably certain. We can never demonstrate 
 the necessity of a cause to every new existence, or new 
 modification of existence, without shewing at the same 
 time the impossibility there is, that any thing can ever 
 begin to exist without some productive principle; and 
 where the latter proposition cannot be prov'd, we must 
 despair of ever being able to prove the former. Now 
 that the latter proposition is utterly incapable of a 
 demonstrative proof, we may satisfy ourselves by con- 
 sidering, that as all distinct ideas are separable from 
 each other, and as the ideas of cause and effect are 
 evidently distinct, 'twill be easy for us to conceive any 
 object to be non-existent this moment, and existent 
 the next, without conjoining to it the distinct idea of 
 a cause or productive principle. The separation, there- 
 fore, of the idea of a cause from that of a beginning 
 of existence, is plainly possible for the imagination; 
 and consequently the actual separation of these objects 
 is so far possible, that it implies no contradiction nor 
 absurdity; and is therefore incapable of being refuted 
 by any reasoning from mere ideas; without which 'tis 
 impossible to demonstrate the necessity of a cause. 
 
 Accordingly we shall find upon examination, that 
 every demonstration, which has been produc'd for the 
 necessity of a cause, is fallacious and sophistical. 
 All the points of time and place,^ say some philoso- 
 phers, in which we can suppose any object to begin to 
 exist, are in themselves equal; and unless there be 
 some cause, which is peculiar to one time and to one 
 place, and which by that means determines and fixes 
 the existence, it must remain in eternal suspence; and 
 
 1 Mr. Hobbea. 
 
SECT. Ill BOOK I. OF THE UNDERSTANDING 199 
 
 the object can never begin to be, for want of some- 
 thing to fix its beginning. But I ask ; Is there any more 
 difficulty in supposing the time and place to be fix'd 
 without a cause, than to suppose the existence to be 
 determin'd in that manner? The first question that 
 occurs on this subject is always, whether the object 
 shall exist or not: The next, when and where it shall 
 begin to exist. If the removal of a cause be intuitively 
 absurd in the one case, it must be so in the other: 
 And if that absurdity be not clear without a proof in 
 the one case, it will equally require one in the other. 
 The absurdity, then, of the one supposition can never 
 be a proof of that of the other; since they are both 
 upon the same footing, and must stand or fall by the 
 same reasoning. 
 
 The second argument,^ which I find us'd on this 
 head, labours under an equal difficulty. Every thing, 
 'tis said, must have a cause ; for if any thing wanted a 
 cause, if would produce itself; that is, exist before it 
 existed; which is impossible. But this reasoning is 
 plainly unconclusive ; because it supposes, that in our 
 denial of a cause we still grant what we expressly 
 deny, vis. that there must be a cause ; which therefore 
 is taken to be the object itself; and that, no doubt, is 
 an evident contradiction. But to say that any thing is 
 produc'd, or to express myself more properly, comes 
 into existence, without a cause, is not to affirm, that 
 'tis itself its own cause ; but on the contrary in exclud- 
 ing all external causes, excludes a fortiori the thing 
 itself which is created. An object, that exists abso- 
 lutely without any cause, certainly is not its own cause ; 
 and when you assert, that the one follows from the 
 other, you suppose the very point in question, and take 
 
 2 Dr. Clarke and others. 
 
 X 
 
 X 
 
v^ 
 
 200 A TREATISE OF HUMAN NATURE PART III 
 
 it for granted, that 'tis utterly impossible any thing 
 can ever begin to exist without a cause, but that upon 
 the exclusion of one productive principle, we must 
 still have recourse to another. 
 
 'Tis exactly the same case with the^ third argu- 
 ment, which has been employ'd to demonstrate the 
 necessity of a cause. Whatever is produc'd without 
 any cause, is produc'd by nothing; or in other words, 
 has nothing for its cause. But nothing can never be 
 a cause, no more than it can be something, or equal 
 to two right angles. By the same intuition, that we 
 perceive nothing not to be equal to two right angles, 
 or not to be something, we perceive, that it can never 
 be a cause ; and consequently must perceive, that every 
 object has a real cause of its existence. 
 
 I believe it will not be necessary to employ many 
 words in shewing the weakness of this argument, after 
 what I have said of the foregoing. They are all of 
 them founded on the same fallacy, and are deriv'd 
 from the same turn of thought. 'Tis sufficient only to 
 observe, that when we exclude all causes we really 
 do exclude them, and neither suppose nothing nor the 
 object itself to be the causes of the existence; and 
 consequently can draw no argument from the absurd- 
 ity of these suppositions to prove the absurdity of that 
 exclusion. If every thing must have a cause, it fol- 
 lows, that upon the exclusion of other causes we must 
 accept of the object itself or of nothing as causes. 
 But 'tis the very point in question, whether every 
 thing must have a cause or not; and therefore, accord- 
 ing to all just reasoning, it ought never to be taken 
 for granted. 
 
 I Mr. Locke, 
 
SECT. Ill BOOK I. OF THE UNDERSTANDING 201 
 
 They are still more frivolous, who say, that every 
 effect must have a cause, because 'tis imply'd in the 
 very idea of effect. Every effect necessarily pre-sup- 
 poses a cause; effect being a relative term, of which 
 cause is the correlative. But this does not prove, that 
 every being must be preceded by a cause; no more 
 than it follows, because every husband must have a 
 wife, that therefore every man must be marry'd. The 
 true state of the question is, whether every object, 
 which begins to exist, must owe its existence to a 
 cause; and this I assert neither to be intuitively nor 
 demonstratively certain, and hope to have prov'd it 
 sufficiently by the foregoing arguments. 
 
 Since it is not from knowledge or any scientific 
 reasoning, that we derive the opinion of the necessity 
 of a cause to every new production, that opinion must 
 necessarily arise from observation and experience. 
 The next question, then, shou'd naturally be, hozv expe- 
 rience gives rise to such a principle? But as I find 
 ir"wiTFEie~more convenient to sink this question in the 
 following. Why we conclude, that such particular 
 causes must necessarily have such particular effects, 
 and why we form an inference from one to another? 
 we shall make that the subject of our future enquiry. 
 'Twill, perhaps, be found in the end, that the same 
 answer will serve for both questions. 
 
 * 5jC 5fS * * * 
 
 3): if. He in if 4c 
 
 / 
 

 I 
 
 Section XIV. 
 Of the idea of necessary connexion. 
 
 Having thus explain'd the manner, in which we 
 reason beyond our immediate impressions, and con- 
 clude that such particular causes must have such par- 
 ticular effects; we must now return upon our foot- 
 steps to examine that question, which^ first occur'd 
 to us, and which we dropt in our way, vis. What is 
 our idea of necessity, when we say that two objects 
 are necessarily connected together. Upon this head 
 I repeat what I have often had occasion to observe, 
 that as we have no idea, that is not deriv'd from an 
 impression, we must find some impression, that gives 
 rise to this idea of necessity, if we assert we have really 
 such an idea. In order to this I consider, in what 
 objects necessity is commonly suppos'd to lie; and 
 finding that it is always ascrib'd to causes and effects, 
 I turn my eye to two objects suppos'd to be plac'd in 
 that relation; and examine them in all the situations, 
 of which they are susceptible. I immediately perceive, 
 that they are contiguous in time and place, and that 
 the object we call cause precedes the other we call 
 effect. In no one instance can I go any farther, nor is 
 it possible for me to discover any third relation betwixt 
 these objects. I therefore enlarge my view to com- 
 prehend several instances; where I find like objects 
 always existing in like relations of contiguity and suc- 
 cession. At first sight this seems to serve but little 
 
 1 Sect. 2. 
 
SECT. XIV BOOK I. OF THE UNDERSTANDING 203 
 
 to my purpose. The reflection on several instances 
 only repeats the same objects ; and therefore can never 
 give rise to a new idea. But upon farther enquiry I 
 find, that the repetition is not in every particular the 
 same, but produces a new impression, and by that 
 means the idea, which I at present examine. For after 
 a frequent repetition, I find, that upon the appear- 
 ance of one of the objects, the mind is determined 
 by custom to consider its usual attendant, and to con- 
 sider it in a stronger light upon account of its rela- 
 tion to the first object. 'Tis this impression, then, or 
 determination, which affords me the idea of necessity. 
 I doubt not but these consequences will at first 
 sight be received without difficulty, as being evident 
 deductions from principles, which we have already 
 establish'd, and which we have often employ'd in our 
 reasonings. This evidence both in the first principles, 
 and in the deductions, may seduce us unwarily into the 
 conclusion, and make us imagine it contains nothing 
 extraordinary, nor worthy of our curiosity. But the' 
 such an inadvertence may facilitate the reception of this 
 reasoning, 'twill make it be the more easily forgot; 
 for which reason I think it proper to give warning, 
 that I have just now examin'd one of the most sublime 
 questions in philosophy, vis. that concerning the power 
 and efficacy of causes; where all the sciences seem so 
 much interested. Such a warning will naturally rouze 
 up the attention of the reader, and make him desire 
 a more full account of my doctrine, as well as of the 
 arguments, on which it is founded. This request is 
 so reasonable, that I cannot refuse complying with it; 
 especially as I am hopeful that these principles, the 
 more they are examin'd, will acquire the more force 
 and evidence. 
 
204 A TREATISE OF HUMAN NATURE PART III 
 
 There is no question, which on account of its im- 
 portance, as well as difficulty, has caus'd more disputes 
 both among antient and modern philosophers, than this 
 concerning the efficacy of causes, or that quality which 
 makes them be followed by their effects. But before 
 they enter'd upon these disputes, methinks it wou'd not 
 have been improper to have examin'd what idea we 
 have of that efficacy, which is the subject of the con- 
 troversy. This is what I find principally wanting in 
 their reasonings, and what I shall here endeavour to 
 supply. 
 
 I begin with observing that the terms of efficacy, 
 agency, power, force, energy, necessity, connexion, and 
 productive quality, are all nearly synonimous; and 
 therefore 'tis an absurdity to employ any of them in 
 defining the rest. By this observation we reject at 
 once all the vulgar definitions, which philosophers have 
 given of power and efficacy; and instead of searching 
 for the idea in these definitions, must look for it in the 
 impressions, from which it is originally deriv'd. If it 
 be a compound idea, it must arise from compound im- 
 pressions. If simple, from simple impressions. 
 
 I believe the most general and most popular expli- 
 cation of this matter, is to say,^ that finding from 
 experience, that there are several new productions in 
 matter, such as the motions and variations of body, 
 and concluding that there must somewhere be a power 
 capable of producing them, we arrive at last by this 
 reasoning at the idea of power and efficacy. But to 
 be convinc'd that this explication is more popular than 
 philosophical, we need but reflect on two very obvious 
 principles. First, That reason alone can never give 
 rise to any original idea, and secondly, that reason, as 
 
 1 See Mr. Locke; chapter of Power. 
 
SECT. XIV BOOK I. OF THE UNDERSTANDING 
 
 \ 
 
 on- \ 
 
 distinguish'd from experience, can never make us con- 
 clude, that a cause or productive quality is absolutely 
 requisite to every beginning of existence. Both these 
 considerations have been sufficiently explain'd; and 
 therefore shall not at present be any farther insisted 
 on. " 
 
 I shall only infer from them, that since reason can 
 never give rise to the idea of efficacy, that idea must 
 be deriv'd from experience, and from some particular 
 instances of this efficacy, which make their passage 
 into the mind by the common channels of sensation or 
 reflection. Ideas always represent their objects or 
 impressions; and vice versa, there are some objects 
 necessary to give rise to every idea. If we pretend, 
 therefore, to have any just idea of this efficacy, we 
 must produce some instance, wherein the efficacy 
 is plainly discoverable to the mind, and its opera- 
 tions obvious to our consciousness or sensation. 'By 
 the refusal of this, we acknowledge, that the idea is 
 impossible and imaginary ; since the principle of innate 
 ideas, which alone can save us from this dilemma, has 
 been already refuted, and is now almost universally 
 rejected in the learned world. Our present business, 
 then, must be to find some natural production, where 
 the operation and efficacy of a cause can be clearly 
 conceiv'd and comprehended by the mind, without any ^ 
 danger of obscurity or mistake. — ""^""^ 
 
 In this research we meet with very little encourage- 
 ment from that prodigious diversity, which is found in 
 the opinions of those philosophers, who have pretended 
 to explain the secret force and energy of causes. ^ 
 There are some, who maintain, that bodies operate by 
 
 1 See Father Malhranche^ Book VI., Part II., chap. 3, and the 
 illustrations upon it. 
 
2o6 A TREATISE OF HUMAN NATURE PART III 
 
 their substantial form; others, by their accidents or 
 quahties ; several, by their matter and form ; some, by 
 their form and accidents ; others, by certain virtues and 
 faculties distinct from all this. All these sentiments 
 again are mix'd and vary'd in a thousand different 
 ways; and form a strong presumption, that none of 
 them have any solidity or evidence, and that the sup- 
 position of an efficacy in any of the known qualities 
 of matter is entirely without foundation. This pre- 
 sumption must encrease upon us, when we consider, 
 that these principles of substantial forms, and acci- 
 dents, and faculties, are not in reality any of the known 
 properties of bodies, but are perfectly unintelligible 
 and inexplicable. For 'tis evident philosophers wou'd 
 never have had recourse to such obscure and uncertain 
 principles had they met with any satisfaction in such 
 as are clear and intelligible ; especially in such an affair 
 as this, which must be an object of the simplest under- 
 standing, if not of the senses. Upon the whole, we 
 may conclude, that 'tis impossible in any one instance 
 to shew the principle, in which the force and agency 
 of a cause is plac'd ; and that the most refin'd and most 
 vulgar understandings are equally at a loss in this 
 particular. If any one think proper to refute this 
 assertion, he need not put himself to the trouble of 
 inventing any long reasonings; but may at once shew 
 us an instance of a cause, where we discover the power 
 or operating principle. This defiance we are oblig'd 
 frequently to make use of, as being almost the only 
 means of proving a negative in philosophy. 
 
 The small success, which has been met with in all 
 the attempts to fix this power, has at last oblig'd phi- 
 losophers to conclude, that the ultimate force and effi- 
 cacy of nature is perfectly unknown to us, and that 
 
SECT. XIV BOOK I. OF THE UNDERSTANDING 207 
 
 'tis in vain we search for it in all the known qualities 
 of matter. In this opinion they are almost unanimous ; 
 and 'tis only in the inference they draw from it, that 
 they discover any difference in their sentiments. For 
 some of them,- as the Cartesians in particular, having 
 establish'd it as a principle, that we are perfectly ac- 
 quainted with the essence of matter, have very natur- 
 ally inferr'd, that it is endow'd with no efficacy, and 
 that 'tis impossible for it of itself to communicate 
 motion, or produce any of those effects, which we 
 ascribe to it. As the essence of matter consists in 
 extension, and as extension implies not actual motion, 
 but only mobility; they conclude, that the energy, 
 which produces the motion, cannot lie in the extension. 
 
 This conclusion leads them into another, which 
 they regard as perfectly unavoidable. Matter, say 
 they, is in itself entirely unactive, and depriv'd of any 
 power, by which it may produce, or continue, or com- 
 municate motion: But since these effects are evident 
 to our senses, and since the power, that produces them, 
 must be plac'd somewhere, it must lie in the Deity, 
 or that divine being, who contains in his nature all 
 excellency and perfection. 'Tis the deity, therefore, 
 who is the prime mover of the universe, and who not 
 only first created matter, and gave it it's original im- 
 pulse, but likewise by a continu'd exertion of omnipo- 
 tence, supports its existence, and successively bestows 
 on it all those motions, and configurations, and quali- 
 ties, with which it is endow'd. 
 
 This opinion is certainly very curious, and well 
 worth our attention; but 'twill appear superfluous to 
 examine it in this place, if we reflect a moment on our 
 present purpose in taking notice of it. We have estab- 
 lish'd it as a principle, that as all ideas are deriv'd 
 
2o8 A TREATISE OF HUMAN NATURE PART III 
 
 from impressions, or some precedent perceptions, 'tis 
 impossible we can have any idea of power and efficacy, 
 unless some instances can be produc'd, wherein this 
 power is perceiv'd to exert itself. Now as these in- 
 stances can never be discovered in body, the Cartesians, 
 proceeding upon their principle of innate ideas, have 
 had recourse to a supreme spirit or deity, whom they 
 consider as the only active being in the universe, and 
 as the immediate cause of every alteration in matter. 
 But the principle of innate ideas being allow'd to be 
 false, it follows, that the supposition of a deity can 
 serve us in no stead, in accounting for that idea of 
 agency, which we search for in vain in all the objects 
 which are presented to our senses, or which we are 
 internally conscious of in our own minds. For if 
 every idea be deriv'd from an impression, the idea of 
 a deity proceeds from the same origin; and if no 
 impression, either of sensation or reflection, implies 
 any force or efficacy, 'tis equally impossible to discover 
 or even imagine any such active principle in the deity. 
 Since these philosophers, therefore, have concluded, 
 that matter cannot be endow 'd with any efficacious 
 principle, because 'tis impossible to discover in it such 
 a principle; the same course of reasoning shou'd de- 
 termine them to exclude it from the supreme being. 
 Or if they esteem that opinion absurd and impious, as 
 it really is, I shall tell them how they may avoid it; 
 and that is, by concluding from the very first, that 
 they have no adequate idea of power or efficacy in any 
 object; since neither in body nor spirit, neither in 
 superior nor inferior natures, are they able to discover 
 one single instance of it. 
 
 The same conclusion is unavoidable upon the hy- 
 pothesis of those, who maintain the efficacy of second 
 
SECT. XIV BOOK I. OF THE UNDERSTANDING 209 
 
 causes, and attribute a derivative, but a real power and 
 energy to matter. For as they confess, that this energy 
 Hes not in any of the known qualities of matter, the 
 difficulty still remains concerning the origin of its idea. 
 If we have really an idea of power, we may attribute 
 power to an unknown quality: But as 'tis impossible, 
 that that idea can be deriv'd from such a quality, and 
 as there is nothing in known qualities, which can pro- 
 duce it; it follows that we deceive ourselves, when we 
 imagine we are possest of any idea of this kind, after 
 the manner we commonly understand it. All ideas are 
 deriv'd from, and represent impressions. We never 
 have any impression, that contains any power or effi- 
 cacy. We never therefo re have an y idea of power. 
 
 It has been establish'd as a certain principle, that 
 general or abstract ideas are nothing but individual 
 ones taken in a certain light, and that, in reflecting 
 on any object, 'tis as impossible to exclude from our 
 thought all particular degrees of quantity and quality 
 as from the real nature of things. If we be possest, 
 therefore, of any idea of power in general, we must 
 also be able to conceive some particular species of it; 
 and as power cannot subsist alone, but is always re- 
 garded as an attribute of some being or existence, we 
 must be able to place this power in some particular 
 being, and conceive that being as endow'd with a real 
 force and energy, by which such a particular effect 
 necessarily results from its operation. We must dis- 
 tinctly and particularly conceive the connexion betwixt 
 the cause and effect, and be able to pronounce, from 
 a simple view of the one, that it must be follow'd or 
 preceded by the other. This is the true manner of 
 conceiving a particular power in a particular body: 
 and a general idea being impossible without an indi- 
 
210 A TREATISE OF HUMAN NATURE PART III 
 
 vidual; where the latter is impossible, 'tis certain the 
 former can never exist. Now nothing is more evident, 
 than that the human mind cannot form such an idea 
 of two objects, as to conceive any connexion betwixt 
 them, or comprehend distinctly that power and efficacy, 
 by which they are united. Such a connexion wou'd 
 amount to a demonstration, and wou'd imply the abso- 
 lute impossibility for the one object not to follow, or 
 to be conceiv'd not to follow upon the other: Which 
 kind of connexion has already been rejected in all 
 cases. If any one is of a contrary opinion, and thinks 
 he has attain'd a notion of power in any particular 
 object, I desire he may point out to me that object. 
 But till I meet with such-a-one, which I despair of, I 
 cannot forbear concluding, that since we can never 
 distinctly conceive how any particular power can pos- 
 sibly reside in any particular object, we deceive our- 
 selves in imagining we can form any such general 
 idea. 
 
 Thus upon the whole we may infer, that when we 
 talk of any being, whether of a superior or inferior 
 nature, as endow'd with a power or force, proportion'd 
 to any effect ; when we speak of a necessary connexion 
 betwixt objects, and suppose, that this connexion de- 
 pends upon an efficacy or energy, with which any of 
 these objects are endow'd; in all these expressions, so 
 apply'd, we have really no distinct meaning, and make 
 use only of common words, without any clear and 
 determinate ideas. But as 'tis more probable, that 
 these expressions do here lose their true meaning by 
 being wrong apply d, than that they never have any 
 meaning; 'twill be proper to bestow another consider- 
 ation on this subject, to see if possibly we can discover 
 the nature and origin of those ideas, we annex to them. 
 
SECT. XIV BOOK L OF THE UNDERSTANDING 211 
 
 Suppose two objects to be presented to us, of which 
 the one is the cause and the other the effect ; 'tis plain, 
 that from the simple consideration of one, or both 
 these objects we never shall perceive the tie, by which 
 they are united, or be able certainly to pronounce, that 
 there is a connexion betwixt them. Tis not, there- 
 fore, from any one instance, that we arrive at the 
 idea of cause and effect, of a necessary connexion of 
 power, of force, of energy, and of efficacy. Did we 
 never see any but particular conjunctions of objects, 
 entirely different from each other, we shou'd never be 
 able to form any such ideas. 
 
 But again; suppose we observe several instances, 
 in which the same objects are always conjoin'd to- 
 gether, we immediately conceive a connexion betwixt 
 them, and begin to draw an inference from one to 
 another. This multiplicity of resembling instances, 
 therefore, constitutes the very essence of power or 
 connexion, and is the source, from which the idea of 
 it arises. In order, then, to understand the idea of 
 power, we must consider that multiplicity; nor do I 
 ask more to give a solution of that difficulty, which 
 has so long perplex'd us. For thus I reason. The 
 repetition of perfectly similar instances can never alone 
 give rise to an original idea, different from what is to 
 be found in any particular instance, as has been ob- 
 serv'd, and as evidently follows from our fundamen- 
 tal principle, that all ideas are copy'd from impressions. 
 Since therefore the idea of power is a new original 
 idea, not to be found in any one instance, and which 
 yet arises from the repetition of several instances, it 
 follows, that the repetition alone has not that effect, 
 but must either discover or produce something new, 
 which is the source of that idea. Did the repetition 
 
212 A TREATISE OF HUMAN NATURE PART III 
 
 neither discover nor produce any thing new, our ideas 
 might be multiply 'd by it, but wou'd not be enlarg'd 
 above what they are upon the observation of one single 
 instance. Every enlargement, therefore, (such as the 
 idea of power or connexion) which arises from the 
 multiplicity of similar instances, is copy'd from some 
 effects of the multiplicity, and will be perfectly under- 
 stood by understanding these effects. Wherever we 
 find any thing new to be discover'd or produc'd by the 
 repetition, there we must place the power, and must 
 never look for it in any other object. 
 
 But 'tis evident, in the first place, that the repeti- 
 tion of like objects in like relations of succession and 
 contiguity discovers nothing new in any one of them; 
 since we can draw no inference from it, nor make it a 
 subject either of our demonstrative or probable rea- 
 sonings ;i as has been already prov'd. Nay suppose we 
 cou'd draw an inference, 'twou'd be of no consequence 
 in the present case; since no kind of reasoning can 
 give rise to a new idea, such as this of power is ; but 
 wherever we reason, we must antecedently be possest 
 of clear ideas, which may be the objects of our reason- 
 ing. The conception always precedes the understand- 
 ing; and where the one is obscure, the other is uncer- 
 tain; where the one fails, the other must fail also. 
 
 Secondly, 'Tis certain that this repetition of similar 
 objects in similar situations produces nothing new 
 either in these objects, or in any external body. For 
 'twill readily be allow'd, that the several instances we 
 have of the conjunction of resembling causes and 
 effects are in themselves entirely independent, and that 
 the communication of motion, which I see result at 
 present from the shock of two billiard-balls, is totally 
 
 1 Sect. 6. 
 
SECT. XIV BOOK L OF THE UNDERSTANDING 213 
 
 distinct from that which I saw result from such an 
 impulse a twelve-month ago. These impulses have no 
 influence on each other. They are entirely divided by 
 time and place; and the one might have existed and 
 communicated motion, tho' the other never had been 
 in being. 
 
 There is, then, nothing new either discover'd or 
 produc'd in any objects by their constant conjunction, 
 and by the uninterrupted resemblance of their rela- 
 tions of succession and contiguity. But 'tis from this 
 resemblance, that the ideas of necessity, of power, and 
 of efficacy, are deriv'd. These ideas, therefore, rep- 
 resent not any thing, that does or can belong to the 
 objects, which are constantly conjoin'd. This is an 
 argument, which, in every view we can examine it, 
 will be found perfectly unanswerable. Similar in- 
 stances are still the first source of our idea of power 
 or necessity ; at the same time that they have no influ- 
 ence by their similarity either on each other, or on any 
 external object. We must therefore, turn ourselves 
 to some other quarter to seek the origin of that idea. 
 
 Tho' the several resembling instances, which give 
 rise to the idea of power, have no influence on each 
 other, and can never produce any new quality in the 
 object, which can be the model of that idea, yet the 
 observation of this resemblance produces a new im- 
 pression in the mind, which is its real model. For 
 after we have observ'd the resemblance in a sufficient 
 number of instances, we immediately feel a determin- 
 ation of the mind to pass from one object to its usual 
 attendant, and to conceive it in a stronger light upon 
 account of that relation. This determination is the 
 only effect of the resemblance; and therefore must be 
 the same with power or efficacy, whose idea is de- 
 
214 A TREATISE OF HUMAN NATURE PART III 
 
 riv'd from the resemblance. The several instances of 
 resembling conjunctions lead us into the notion of 
 power and necessity. These instances are in them- 
 selves totally distinct from each other, and have no 
 union but in the mind, which observes them, and col- 
 lects their ideas. Necessity, then, is the effect of this 
 observation, and is nothing but an internal impres- 
 sion of the mind, or a determination to carry our 
 thoughts from one object to another. Without con- 
 sidering it in this view, we can never arrive at the most 
 distant notion of it, or be able to attribute it either 
 to external or internal objects, to spirit or body, to 
 causes or effects. 
 
 The necessary connexion betwixt causes and effects 
 is the foundation of our inference from one to the 
 other. The foundation of our inference is the tran- 
 sition arising from the accustom'd union. These are, 
 therefore, the same. 
 
 The idea of necessity arises from some impression. 
 There is no impression convey'd by our senses, which 
 can give rise to that idea. It must, therefore, be 
 deriv'd from some internal impression, or impression 
 of reflexion. There is no internal impression, which 
 has any relation to the present business, but that pro- 
 pensity, which custom produces, to pass from an object 
 to the idea of its usual attendant. This therefore is 
 the essence of necessity. Upon the whole, necessity 
 is something, that exists in the mind, not in objects; 
 nor is it possible for us ever to form the most distant 
 idea of it, consider'd as a quality in bodies. Either 
 we have no idea of necessity, or necessity is nothing 
 but that determination of the thought to pass from 
 causes to effects and from effects to causes, according 
 to their experienced union. 
 
SECT. XIV BOOK I. OF THE UNDERSTANDING 215 
 
 Thus as the necessity, which makes two times two 
 equal to four, or three angles of a triangle equal to 
 two right ones, lies only in the act of the understand- 
 ing, by which we consider and compare these ideas; 
 in like manner the necessity or power, which unites 
 causes and effects, lies in the determination of the 
 mind to pass from the one to the other. The efficacy 
 or energy of causes is neither plac'd in the causes 
 themselves, nor in the deity, nor in the concurrence of 
 these two principles ; but belongs entirely to the soul, 
 which considers the union of two or more objects in 
 all past instances. 'Tis here that the real power of 
 causes is plac'd, along with their connexion and neces- 
 sity. 
 
 I am sensible, that of all the paradoxes, which I 
 have had, or shall hereafter have occasion to advance 
 in the course of this treatise, the present one is the 
 most violent, and that 'tis merely by dint of solid 
 proof and reasoning I can ever hope it will have ad- 
 mission, and'^overcdfne the inveterate prejudices of 
 mankind. Before we are reconcil'd to this doctrine, 
 how often must we repeat to ourselves, that the simple 
 view of any two objects or actions, however related, 
 can never give us any idea of power, or of a connexion 
 betwixt them : that this idea arises from the repetition 
 of their union : that the repetition neither discovers nor 
 causes any thing in the objects, but has an influence 
 only on the mind, by that customary transition it pro- 
 duces : that this customary transition is, therefore, the 
 same with the power and necessity; which are conse- 
 quently qualities of perceptions, not of objects, and 
 are internally felt by the soul, and not perceiv'd exter- 
 nally in bodies? There is commonly an astonishment 
 attending every thing extraordinary ; and this astonish- 
 
2i6 A TREATISE OF HUMAN NATURE PART III 
 
 merit changes immediately into the highest degree of 
 esteem or contempt, according as we approve or dis- 
 approve of the subject. I am much afraid, that tho' 
 the foregoing reasoning appears to me the shortest 
 and most decisive imaginable; yet with the generality 
 of readers the biass of the mind will prevail, and give 
 them a prejudice against the present doctrine. 
 
 This contrary biass is easily accounted for. 'Tis a 
 common observation, that the mind has a great pro- 
 pensity to spread itself on external objects, and to 
 conjoin with them any internal impressions, which 
 they occasion, and which always make their appear- 
 ance at the same time that these objects discover them- 
 selves to the senses. Thus as certain sounds and smells 
 are always found to attend certain visible objects, we 
 naturally imagine a conjunction, even in place, betwixt 
 the objects and qualities, tho' the qualities be of such 
 a nature as to admit of no such conjunction, and really 
 exist no where. But of this more fully^ hereafter. 
 Mean while 'tis sufficient to obseTve, that tlie same pro- 
 pensity is the reason, why we suppose necessity and 
 power to lie in the objects we consider, not in our 
 mind, that considers them; notwithstanding it is not 
 possible for us to form the most distant idea of that 
 quality, when it is not taken for the determination of 
 the mind, to pass from the idea of an object to that 
 of its usual attendant. 
 
 But tho' this be the only reasonable account we 
 can give of necessity, the contrary notion is so riveted 
 in the mind from the principles above-mention'd, that 
 I doubt not but my sentiments will be treated by many 
 as extravagant and ridiculous. What! the efficacy of 
 causes lie in the determination of the mind! As if 
 
 1 Part IV., Sect. 5. 
 
SECT. XIV BOOK I. OF THE UNDERSTANDING 217 
 
 causes did not operate entirely independent of the 
 mind, and wou'd not continue their operation, even 
 tho' there was no mind existent to contemplate them, 
 or reason concerning them. Thought may well depend 
 on causes for its operation, but not causes on thought. 
 This is to reverse the order of nature, and make that 
 secondary, which is really primary. To every opera- 
 tion there is a power proportion'd ; and this power 
 must be plac'd on the body, that operates. If we 
 remove the power from one cause, we must ascribe it 
 to another: But to remove it from all causes, and 
 bestow it on a being, that is no ways related to the 
 cause or effect, but by perceiving them, is a gross 
 absurdity, and contrary to the most certain principles 
 of human reason. 
 
 I can only reply to all these arguments, that the 
 case is here much the same, as if a blind man shou'd 
 pretend to find a great many absurdities in the sup- 
 position, that^the colour of scarlet is not the same with 
 the sou'ndjj^LjJt^un^netno r lig ht^jj^^ .<;amp wit]j_.gn1irl- 
 ity. if we have really_no idea ofji power or^^cac^ 
 in any object, or of any real connexion betwLsd: causes ^ 
 and effects, 'twill be to little purpose to prove, that 
 an efficacy is necessary in all operations. We do not 
 understand our own meaning in talking so, but igno- 
 rantly confound ideas, which are entirely distinct from 
 each other. I am, indeed, ready to allow, that there 
 may be several qualities both in material and imma- 
 terial objects, with which we are utterly unacquainted; 
 and if we please to call these power or efficacy, 
 'twill be of little consequence to the world. But 
 when, instead of meaning these unknown quali- 
 ties, we make the terms of power and efficacy signify 
 something, of which we have a clear idea, and which is 
 
2i8 A TREATISE OF HUMAN NATURE PART III 
 
 incompatible with those objects, to which we apply it, 
 obscurity and error begin then to take place, and we 
 are led astray by a false philosophy. This is the case, 
 when we transfer the determination of the thought to 
 external objects, and suppose any real intelligible con- 
 nexion betwixt them; that being a quality, which can 
 only belong to the mind that considers them. 
 
 As to what may be said, that the operations of 
 nature are independent of our thought and reasoning, 
 I allow it; and accordingly have observ'd, that objects 
 bear to each other the relations of contiguity and suc- 
 cession; that like objects may be observ'd in several 
 instances to have like relations; and that all this is 
 independent of, and antecedent to the operations of 
 the understanding. But if we go any farther, and 
 ascribe a power or necessary connexion to these ob- 
 jects; this is what we can never observe in them, but 
 must draw the idea of it from what we feel internally 
 in contemplating them. And this I carry so far, that^ 
 
 I am _| :g3dv to rnnygd- n^v jTrp^pnt ^ r^agnn^ mto an 
 
 instance of it, by a subtilityTwrnchit will nnt ISf ^lififiT 
 cult to CQffiprehend. 
 
 When any object is presented to us, it immediately 
 conveys to the mind a lively idea of that object, whkh 
 is usually found to attend it; and this determination 
 of the mind forms the necessary connexion of theses 
 objects. But when we change the point of view, from^ 
 the objects to the perceptions; in that case the impres- 
 sion is to be considered as the cause, and the lively 
 idea as the effect; and their necessary connexion is 
 that new determination, which we feel to pass from 
 the idea of the one to that of the other. The uniting 
 principle among our internal perceptions is as unin- 
 telligible as that among external objects, and is not 
 
SECT. XIV BOOK I. OF THE UNDERSTANDING 219 
 
 known to us any other way than by experience. Now 
 the nature and effects of experience have been already 
 sufficiently examin'd and explain'd. It never gives us 
 any insight into the internal structure or operating 
 principle of objects, but only accustoms the mind to 
 pass from one to another. 
 
 Tis now time to collect all the different parts of 
 this reasoning, and by joining them together form an 
 exact definition of the relation of cause and effect, 
 which makes the subject of the present enquiry. This 
 order wou'd not have been excusable, of first examin- 
 ing our inference from the relation before we 
 had explain'd the relation itself, had it been pos- 
 sible to proceed in a different method. But as the 
 nature of the relation depends so much on that of the 
 inference, we have been oblig'd to advance in this 
 seemingly preposterous manner, and make use of 
 terms before we were able exactly to define them, or 
 fix their meaning. We shall now correct this fault 
 by giving a precise definition of cause and effect. 
 
 There may two definitions be given of this relation, 
 which are only different, by their presenting a different 
 view of the same object, and making us consider it 
 either as a philosophical or as a natural relation; 
 either as a comparison of two ideas, or as an associa- 
 tion betwixt them. We may define a cause to be *An 
 o bject precedent and contiguo us to another, and where 
 all theobjects resembling the former are plac'd in like 
 relations of precedency and contiguity to those objects, 
 that resemble the latter.' If this definition be esteem'd 
 defective, because drawn from objects foreign to the 
 cause, we may substitute this other definition in its 
 place, zi2. 'A cause is an object precedent and con- 
 tiguous to another, and so united with it, that the idea 
 
220 A TREATISE OF HUMAN NATURE. PART III 
 
 of the one determines the mind to form the idea of 
 tEe other, and the impression of the one to form a 
 morejively idea of the other/ Shou'd this definition 
 also be rejected for the same reason, I know no other 
 remedy, than that the persons, who express this deH- 
 cacy, should substitute a juster definition in its place. 
 But for my part I must own my incapacity for 
 such an undertaking. When I examine with the ut- 
 most accuracy those objects, which are commonly 
 denominated causes and effects, I find, in considering 
 a single instance, that the one object is precedent and 
 contiguous to the other; and in inlarging my view to 
 consider several instances, I find only, that like objects 
 are constantly plac'd in like relations of succession and 
 contiguity. Again, when I consider the influence of 
 this constant conjunction, I perceive, that such a rela- 
 tion can never be an object of reasoning, and can never 
 operate upon the mind, but by means of custom, which 
 determines the imagination to make a transition from 
 the idea of one object to that of its usual attendant, 
 and from the impression of one to a more lively idea 
 of the other. However extraordinary these sentiments 
 may appear, I think it fruitless to trouble myself with 
 any farther enquiry or reasoning upon the subject, but 
 shall repose myself on them as on established maxims. 
 Twill only be proper, before we leave this subject, 
 to draw some corollaries from it, by which we may 
 remove several prejudices and popular errors, that 
 have very much prevail'd in philosophy. First, We 
 may learn from the foregoing doctrine, that all causes 
 are of the same kind, and that in particular there is 
 no foundation for that distinction, which we sometimes 
 make betwixt efficient causes, and causes sine qua non; 
 or betwixt efficient causes, and formal, and material, 
 
SECT. XIV BOOK I. OF THE UNDERSTANDING 221 
 
 and exemplary, and final causes. For as our idea of 
 efficiency is deriv'd from the constant conjunction of 
 two objects, wherever this is observ'd, the cause is 
 efficient; and where it is not, there can never be a 
 cause of any kind. For the same reason we must 
 reject the distinction betwixt cause and occasion, when 
 suppos'd to signify any thing essentially different from 
 each other. If constant conjunction be imply 'd in 
 what we call occasion, 'tis a real cause. If not, 'tis 
 no relation at all, and cannot give rise to any argu- 
 ment or reasoning. 
 
 Secondly, The same course of reasoning will make 
 us conclude, that there is but one kind of necessity, 
 as there is but one kind of cause, and that the common 
 distinction betwixt moral and physical necessity is 
 without any foundation in nature. This clearly ap- 
 pears from the precedent explication of necessity. 'Tis 
 the constant conjunction of objects, along with the 
 determination of the mind, which constitutes a physi- 
 cal necessity: And the removal of these is the same 
 thing with chance. As objects must either be con- 
 join'd or not, and as the mind must either be deter- 
 min'd or not to pass from one object to another, 'tis 
 impossible to admit of any medium betwixt chance and 
 an absolute -necessity. In weakening this conjunction 
 and determination you do not change the nature of 
 the necessity; since even in the operation of bodies, 
 these have different degrees of constancy and force, 
 without producing a different species of that relation. 
 
 The distinction, which we often make betwixt 
 power and the exercise of it, is equally without foun- 
 dation. 
 
 Thirdly, We may now be able fully to overcome 
 all that repugnance, which 'tis so natural for us to 
 
222 A TREATISE OF HUMAN NATURE. PART III 
 
 entertain against the foregoing reasoning, by which 
 we endeavour'd to prove, that the necessity of a cause 
 to every beginning of existence is not founded on any 
 arguments either demonstrative or intuitive. Such an 
 opinion will not appear strange after the foregoing 
 definitions. If we define a cause to be an object pre- 
 cedent and contiguous to another, and where all the 
 objects resembling the former are plac'd in a like 
 relation of priority and contiguity to those objects, that 
 resemble the laitter; we may easily conceive, that there 
 is no absolute nor metaphysical necessity, that every 
 beginning of existence shou'd be attended with such 
 an object. If we define a cause to be. An object pre- 
 cedent and contiguous to another, and so united with it 
 in the imagination, that the idea of the one determines 
 the mind to form the idea of the other, and the im- 
 pression of the one to form a more lively idea of the 
 other; we shall make still less difficulty of assenting to 
 this opinion. Such an influence on the mind is in 
 itself perfectly extraordinary and incomprehensible; 
 nor can we be certain of its reality, but from experi- 
 ence and observation. 
 
 I shall add as a fourth corrollary, that we can never 
 have reason to believe that any object exists, of which 
 we cannot form an idea. For as all our reasonings 
 concerning existence are deriv'd from causation, and 
 as all our reasonings concerning causation are deriv'd 
 from the experienc'd conjunction of objects, not from 
 any reasoning or reflexion, the same experience must 
 give us a notion of these objects, and must remove all 
 mystery from our conclusions. This is so evident, 
 that 'twou'd scarce have merited our attention, were 
 it not to obviate certain objections of this kind, which 
 might arise against the following reasonings concern- 
 
SECT. XIV BOOK I. OF THE UNDERSTANDING 223 
 
 ing matter and substance. I need not observe, that a 
 full knowledge of the object is not requisite, but only 
 of those qualities of it, which we believe to exist. 
 
THE DOCTRINE OF SUBSTANCE 
 
 SELECTIONS FROM 
 BOOK /., PARTS /., //., IF. 
 
PART I. 
 
 OF IDEAS, THEIR ORIGIN, COMPOSITION, 
 CONNEXION, ABSTRACTION. 
 
 ♦ 5|C ♦ ♦ * * 
 
 ****** 
 
 Section VI. 
 Of modes and substances. 
 
 I wou'd fain ask those philosophers, who found so 
 much of their reasonings on the distinction of sub- 
 stance and accident, and imagine we have clear ideas 
 of each, whether the idea of substance be deriv'd from 
 the impressions of sensation or reflexion? If it be 
 convey 'd to us by our senses, I ask, which of them; 
 and after what manner? If it be perceiv'd by the eyes, 
 it must be colour; if by the ears, a sound; if by the 
 palate, a taste; and so of the other senses. But I 
 believe none will assert, that substance is either a 
 colour, or sound, or a taste. The idea of substance 
 must therefore be deriv'd from an impression of re- 
 flexion, if it really exist. But the impressions of re- 
 flexion resolve themselves into our passions and emo- 
 tions; none of which can possibly represent a sub- 
 stance. We have therefore no idea of substance, dis- s ,/ 
 tinct from that of a collection of particular qualities. X^/' 
 nor have we any other meaning when we either talk 
 or reason concerning it. 
 
 The id ea of a substance as well as that of a mode, 
 is nothing but a collection of simple ideas, that are 
 united by the imagination, and have a particular name 
 
228 A TREATISE OF HUMAN NATURE PART I 
 
 assigned them, by which we are able to recall, either 
 to ourselves or others, that collection. But the differ- 
 ence betwixt these ideas consists in this, that the par- 
 ticular qualities, which form a substance, are com- 
 monly refer'd to an unknown something, in which they 
 are supposed to inhere ; or granting this fiction should 
 not take place, are at least supposed to be closely and 
 inseparably connected by the relations of contiguity 
 and causation. The effect of this is, that whatever 
 new simple quality we discover to have the same con- 
 nexion with the rest, we immediately comprehend it 
 among them, even tho' it did not enter into the first 
 conception of the substance. Thus our idea of gold 
 may at first be a yellow colour, weight, malleableness, 
 fusibility; but upon the discovery of its dissolubility 
 in aqua regia, we join that to the other qualities, and 
 suppose it to belong to the substance as much as if 
 its idea had from the beginning made a part of the 
 compound one. The principle of union being regarded 
 as the chief part of the complex idea, gives entrance 
 to whatever quality afterwards occurs, and is equally 
 comprehended by it, as are the others, which first pre- 
 sented themselves. 
 
 That this cannot take place in modes, is evident 
 from considering their nature. The simple ideas of 
 which modes are formed, either represent qualities, 
 which are not united by contiguity and causation, but 
 are dispers'd in different subjects; or if they be all 
 united together, the uniting principle is not regarded 
 as the foundation of the complex idea. The idea of a 
 dance is an instance of the first kind of modes ; that of 
 beauty of the second. The reason is obvious, why such 
 complex ideas cannot receive any new idea, without 
 changing the*name, which distinguishes the mode. 
 
PART II. 
 OF THE IDEAS OF SPACE AND TIME. 
 
 ***** 5|C 
 
 ****** 
 
 Section VI. 
 Of the idea of existence, and of external existence. 
 
 It may not be amiss, before we leave this subject, 
 to explain the ideas of existence and of external exist- 
 ence ; which have their difficulties, as well as the ideas 
 of space and time. By this means we shall be the better 
 prepar'd for the examination of knowledge and prob- 
 ability, when we understand perfectly all those par- 
 ticular ideas, which may enter into our reasoning. 
 
 There is no impression nor idea of any kind, of 
 which we have any consciousness or memory, that is 
 not conceiv'd as existent; and 'tis evident, that from 
 this consciousness the most perfect idea and assur- 
 ance of being is deriv'd. From hence v/e may form a 
 dilemm.a, the most clear and conclusive that can be 
 imagin'd, viz. tha t since we never remember any idea 
 or impr ession without attributing existence to it, the 
 idea of existence must either be deriv'd from a ^lFtinct 
 impression, conjoin'd with every perception or object 
 of our thought, or must be the very same with the idea 
 of the perception or object. 
 
 As this dilemma is an evident consequence of the 
 principle, that every idea arises from a similar impres- 
 
230 A TREATISE OF HUMAN NATURE PART II 
 
 sion, so our decision betwixt the propositions of the 
 dilemma is no more doubtful. So far from there being 
 any distinct impression, attending every impression 
 and every idea, that I do not think there are any two 
 distinct impressions, which are inseparably conjoin'd. 
 Tho' certain sensations may at one time be united, we 
 quickly find they admit of a separation, and may be 
 presented apart. And thus, tho' every impression and 
 idea we remember be consider'd as existent, thejdea, 
 of existence is not de rived from any particul ar imp res- 
 sion. 
 
 The idea of existence, then, is the very same with 
 the idea of what we conceive to be existent. To reflect 
 on any thing simply, and to reflect on it as existent, 
 are nothing different from each other. That idea, 
 when conjoin'd with the idea of any object, makes no 
 addition to it. Whatever we conceive, we concdvfiJxt 
 be existent . Any idea we please to form is the idea 
 of a being; and the idea of a being is any idea we 
 please to form. 
 
 Whoever opposes this, must necessarily point out 
 that distinct impression, from which the idea of entity 
 is deriv'd, and must prove, that this impression is in- 
 separable from every perception we believe to be exist- 
 ent. This we may without hesitation coticlude to be 
 impossible. 
 
 Our foregoing^ reasoning concerning the distinc- 
 tion of ideas without any real difference will not here 
 ^erve us in any stead. That kind of distinction is 
 founded on the different resemblances, which the same 
 simple idea may have to several different ideas. But 
 no object can be presented resembling some object 
 with respect to its existence, and different from others 
 
 1 Part I., Sect. 7. 
 
SECT. VI BOOK I. OF THE UNDERSTANDING 231 
 
 in the same particular ; since every object, that is pre- 
 sented, must necessarily be existent. 
 
 A like reasoning will account for the idea of exter- 
 nal existence. We may observe, that 'tis universally 
 allow'd by philosophers, and is besides pretty obvious 
 of itself, that nothing is ever really present with the 
 mind but its perceptions or impressions and ideas, and 
 that external objects become known to us only by those 
 perceptions they occasion. To hate, to love, to think, 
 to feel, to see ; all this is nothing but to perceive. 
 
 Now since nothing is ever present to the mind but 
 perceptions, and since all ideas are deriv'd from some- 
 thing antecedently present to the mind ; it follows, that 
 'tis impossible for us so much as to conceive or form 
 an idea of any thing specifically different from 
 ideas and impressions. Let us fix our attention out 
 of ourselves as much as possible : Let us chace our 
 imagination to the heavens, or to the utmost Hmits of 
 the universe; we never really advance a^^;^ beyond 
 ourselves, nor rpn fwirpivp any kind nf existcnc^ . 
 but those p erceptions, which have_ appf^ar'd in th at nar - 
 row compass. This is the universe of the imagination, 
 nor have we any idea but what is there produc'd. 
 
 The farthest we can go towards a mnrfpfinn n^j, 
 external objecta. when suppos'd specifically different 
 from our perceptions, is to form a relative idea o f 
 t hem, without pretending to comprehend the related 
 objects. Generally speaking we do not suppose them 
 specifically different ; but only attribute to them differ- 
 ent relations, connexions and durations. But of this 
 more fully hereafter.^ 
 
 H: * * * * * 
 
 1 Fart IV., Sect. 2. 
 
PART IV. 
 
 OF THE SCEPTICAL AND OTHER SYSTEMS 
 
 OF PHILOSOPHY. 
 
 * 
 
 * 
 
 * * 
 
 * 
 
 * 
 
 * 
 
 * 
 
 * if: 
 
 Section II. 
 
 ^ 
 
 * 
 
 Of scepticism zvith regard to the senses. 
 
 Thus the sceptic still continues to reason and be- 
 lieve, even tho' he asserts, that he cannot defend his 
 reason by reason; and by the same rul e he must asse nt 
 to the principle concerning the existence of body, tho' 
 he cannot pretend by any arguments "of philosophy to 
 maintain its veracity. Nature has not left this to his 
 choice, and has doubtless esteem'd it an affair of too 
 great importance to be trusted to our uncertain rea- 
 sonings and speculations. We may well ask. What 
 causes induce us to believe in the existence of body? 
 but 'tis vain to ask. Whether there be body or not? 
 That is a point, which we must take for granted in all 
 our reasonings. 
 
 The subject, then, of our present enquiry is con- 
 cerning the causes which induce us to believe in the 
 existence of body; and my reasonings on this head I 
 shall begin with a distinction, which at first sight may 
 seem superfluous, but which will contribute very much 
 to the perfect understanding of what follows. We 
 ought to examine apart those two questions, which are 
 commonly confounded together, viz. Wliy we attribut e 
 a^ coNTiNu'p existence \o objects. evetT wh en they are 
 
SECT. II BOOK I. OF THE UNDERSTANDING 233 
 
 not present to the senses; and why we suppose them 
 
 to have an existence distinct from the mind and per- 
 ception. Under this last head I comprehend their 
 situation as well as relations, their external position 
 as well as the independence of their existence and 
 operation. These two questions concerning the con- 
 tinued and distinct existence of body are intimately 
 connected together. For if the object_s of^our senses 
 continue to exist, even . when they are not perceiv'd, 
 Jh pjr pyi sten re, Jg_(^f„_<yjir^f j'.^.d^pPii d ^nt nf and dis- 
 tinct from the perception ; and vice versa, if their 
 existence be independent of the perception and dis- 
 tinct from it, they must continue to exist, even tho' 
 they be not perceiv'd. But tho' the decision of the one 
 question decides the other ; yet that we may the more 
 easily discover the principles of human nature, from 
 whence the decision arises, we shall carry along with 
 us this distinction, and shall consider, whether it_ be 
 the s enses, reason, or the ima^^ inafion, tHat produces 
 the opinion of a continued or of a d'istinct existence. 
 These are the only questions, that are intelligible on 
 the present subject. For as to the notion of external 
 existence, when taken for something specifically dif- 
 ferent from our perceptions,^ we have already shewn 
 its absurdity. <^_ 
 
 To begin with the senses, 'tis evident these facul- 
 ties are incapable of givmg rise to the notion of the 
 continu'd existence of their objects, after they no 
 longer appear to the senses. For that is a contradic- 
 tion in terms, and supposes that the senses continue to 
 operate, even after they have ceas'd all manner of 
 operation. These faculties, therefore, if they have any 
 influence in the present case, must produce the opinion 
 1 Part II., Sect. 6. 
 
234 ^ TREATISE OF HUMAN NATURE PART IV 
 
 • ^'"Df a distinct, not of a continued existence ; and in order 
 to that, must present their impressions either as images 
 and representations, or as these very distinct and 
 external existences. 
 
 That our senses offer not their impressions as the 
 images of somel;hing distinct, or independent, and ex- 
 te rnal, is evident; because they convey to us nothing. 
 but a single perception, and never give us the least 
 intimation of any thing beyond. A single perception 
 can never produce the idea of a double existence, but 
 by some inference either of the reason or imagination. 
 When the mind looks farther than what immediately 
 appears to it, its conclusions can never be put to the 
 account of the senses; and it certainly looks farther, 
 when from a single perception it infers a double exist- 
 ence, and supposes the relations of resemblance and 
 causation betwixt them. 
 
 But tho' we are led after this manner, by the nat- 
 ural propensity of the imagination, to ascribe a con- 
 tinu'd existence to those sensible objects or percep- 
 tions, which we find to resemble each other in their 
 interrupted appearance ; yet a very little reflection and 
 philosophy is sufficient to make us perceive the fallacy 
 of that opinion. I have already observ'd, that there 
 is an intimate connexion betwixt those two principles, 
 of a continu'd and of a distinct or independent exist- 
 ence, and that we no sooner establish the one than the 
 other follows, as a necessary consequence. 'Tis the 
 opinion of a continu'd existence, which first takes place, 
 and without much study or reflection draws the other 
 along with it, wherever the mind follows its first and 
 
SECT. II BOOK I. OF THE UNDERSTANDING 235 
 
 most natural tendency. But when we compare experi- 
 ments, and reason a little upon them, we quickly per- 
 ceixe^ that the, .doctrine of the independent existence 
 of our sensible perceptions is contrary to the plainest 
 experience. This leads us backward upon our foot- 
 steps to perceive our error in attributing a continu'd 
 existence to our perceptions, and is the origin of many 
 very curious opinions, which we shall here endeavour 
 to account for. - ' ' 
 
 'Twill first be proper to observe a few of those 
 experiments, which convince us, that our perceptions 
 are not possest of any independent existence. When 
 we press one eye with a finger, we immediately per- 
 ceive all the objects to become double, and one half 
 of them to be remov'd from their common and natural 
 position. But as we do not attribute a continu'd exist- 
 ence to both these perceptions, and as they are both 
 of the same nature, we clearly perceive, that all pux^ 
 perce2tions are dependent on our organs, and the dis- 
 position of our nerves and animal spirits. This opinion 
 is confirm'd by the seeming encrease and diminution 
 of objects, according to their distance; by the appar- 
 ent alterations in their figure; by the changes in their 
 colour and other qualities from our sickness and dis- 
 tempers; and by an infinite number of other experi- 
 ments of the same kind; from all which we learn, 
 that our sensible perceptions are not possest of any 
 distinct or independent existence. 
 
 The natural consequence of this reasoning shou'd 
 be, that our perceptions have no more a continu'd than 
 an independent existence; and indeed philosophers 
 have so far run into this opinion, that they change 
 their system, and distinguish, (as we shall do for the 
 future) betwixt perceptions and objects, of which the 
 
236 A TREATISE OF HUMAN NATURE PART IV 
 
 former are suppos'd to be interrupted, and perishing, 
 and different at every different return ; the latter to be 
 uninterrupted, and to preserve a continu'd existence and 
 identity. But however philosophical this new system 
 may be esteem'd, I assert that 'tis only a palliative rem- 
 edy, and that it contains all the difficulties of the vulgar 
 system, with some others, that are peculiar to itself. 
 There are no principles either of the understanding 
 or fancy, which lead us directly to embrace this opinion 
 of the double existence of perceptions and objects^ nor 
 can we arrive at it but by passing thro' the common 
 hypothesis of the identity and continuance of our inter- 
 rupted perceptions. Were we not first perswaded, 
 that our perceptions are our only objects, and continue 
 to exist even when they no longer make their appear- 
 1 aiTce to the senses, we shou'd never be led to think, 
 I that our perceptions and objects are different, and that 
 ' our objects alone preserve a continu'd existence. 'The 
 latter hypothesis has no primary recommendation 
 either to reason or the imagination, but acquires all 
 its influence on the imagination from the former.' 
 This proposition contains two parts, which we shall 
 endeavour to prove as distinctly and clearly, as such 
 abstruse subjects will permit. 
 finA^^^"^ As to the first part of the proposition, that this 
 phihsophical hypothesis has no primary recommenda- 
 tion, either to reason or the imagination, we may soon 
 satisfy ourselves with regard to reason by the follow- 
 ing reflections. The only existences, of which we are 
 certain, are perceptions, which being immediately pres- 
 ent to us by consciousness, command our strongest 
 assent, and are the first foundation of all our conclu- 
 sions. The only conclusion we can draw from the 
 existence of one thing to that of another, is by means 
 
SECT, II BOOK I. OF THE UNDERSTANDING 237 
 
 of the relation of cause and effect, which shews, that 
 there is a connexion betwixt them, and that the exist-^ 
 ence of one is dependent on that of the other. Th^ 
 idea of this relation is deriv'd from past experience, 
 by which we find, that two beings are constantly con- 
 Join'd together, and are always present at once to the 
 mind. But as no beings are ever present to the mind 
 but perceptions ; it follows that we may observe a con- 
 junction or a relation of cause and effect between dif- 
 ferent perceptions, but can never observe it between 
 perceptions and objects. 'Tis impossible, therefore, 
 that from the existence or any of the qualities of the 
 former, we can ever form any conclusion concerning 
 the existence of the latter, or ever satisfy our reason 
 in this particular. 
 
 'Tis no less certain, that this philosophical system' 
 has no primary recommendation to the, imagination,^ 
 and that that faculty wou'd never, of itself, and by its 
 original tendency, have fallen upon such a principle. 
 I confess it will be somewhat difficult to prove this 
 to the full satisfaction of the reader ; because it implies 
 a negative, which in many cases will not admit of any 
 positive proof. If any one wou'd take the pains to 
 examine this question, and wou'd invent a system, to 
 account for the direct origin of this opinion from the 
 imagination, we shou'd be able, by the examination 
 of that system, to pronounce a certain judgment in 
 the present subject. Let it be taken for granted, that 
 our perceptions are broken, and interrupted, and how- 
 ever like, are still different from each other; and let 
 any one upon this supposition shew why the fancy, 
 directly and immediately, proceeds to the belief of 
 another existence, resembling these perceptions in their 
 nature, but yet continu'd, and uninterrupted, and iden- 
 
238 A TREATISE OF HUMAN NATURE PART IV 
 
 tical; and after he has done this to my satisfaction, I 
 promise to renounce my present opinion. Mean while 
 I cannot forbear concluding, from the very abstracted- 
 ness and difficulty of the first supposition, that 'tis 
 an improper subject for the fancy to work upon. Who- 
 ever wou'd explain the origin of the common opinion 
 concerning the continu'd and distinct existence of 
 body, must take the mind in its common situation, and 
 must proceed upon the supposition, that our percep- 
 tions are our only objects, and continue to exist even 
 when they are not perceiv'd. Tho' this opinion be 
 false, 'tis the most natural of any, and has alone any 
 primary recommendation to the fancy. 
 
 As to the second part of the proposition, that the 
 philosophical system acquires all its influence on the 
 imagination from the vulgar one; we may observe, 
 that this is a natural and unavoidable consequence of 
 the foregoing conclusion, that it has no primary recom- 
 mendation to reason or the imagination. For as the 
 philosophical system is found by experience to take 
 hold of many minds, and in particular of all those, who 
 reflect ever so little on this subject, it must derive all 
 its authority from the vulgar system; since it has no 
 original authority of its own. The manner, in which 
 these two systems, tho' directly contrary, are con- 
 nected together, may be explain'd, as follows. 
 
 The imagination naturally runs on in this train of 
 thinking. Our perceptions are our only objects: Re- 
 sembling perceptions are the same, however broken or 
 uninterrupted in their appearance: This appearing in- 
 terruption is contrary to the identity : The interruption 
 consequently extends not beyond the appearance, and 
 the perception or object really continues to exist, even 
 when absent from us: Our sensible perceptions have, 
 
SECT. II BOOK I. OF THE UNDERSTANDING 239 
 
 therefore, a continu'd and uninterrupted existence. 
 But as a little reflection destroys this conclusion, that 
 our perceptions have a continu'd existence, by shewing 
 that they have a dependent one, 'twou'd naturally be 
 expected, that we must altogether reject the opinion, 
 that there is such a thing in nature as a continu'd 
 existence, which is preserv'd even when it no longer 
 appears to the senses. The case, however, is other- 
 wise. Philosophers are so far from rejecting the 
 opinion of a continu'd existence upon rejecting that of 
 the independence and continuance of our sensible 
 perceptions, that tho' all sects agree in the latter sen- 
 timent, the former, which is, in a manner, its necessary 
 consequence, has been peculiar to a few extravagant 
 sceptics ; who after all maintain'd that opinion in words 
 only, and were never able to bring themselves sin- 
 cerely to believe it. 
 
 There is a great difference betwixt such opinions 
 as we form after a calm and profound reflection, and 
 such as we embrace by a kind of instinct or natural 
 impulse, on account of their suitableness and conform- 
 ity to the mind. If these opinions become contrary, 
 'tis not difficult to foresee which of them will have 
 the advantage. As long as our attention is bent upon 
 the subject, the philosophical and study 'd principle may 
 prevail ; but the moment we relax our thoughts, nature 
 will display herself, and draw us back to our former 
 opinion. Nay she' has sometimes such an influence, 
 that she can stop our progress, even in the midst of 
 our most profound reflections, and keep us from run- 
 ning on with all the consequences of any philosophical 
 opinion. Thus tho' we clearly perceive the de pend- 
 ence and interruptloiToTour perceptio ns, we stop short 
 in our career, and never upon that account reject the 
 
240 A TREATISE OF HUMAN NATURE PART IV 
 
 notion of an independent and continird existence. 
 That opinion has taken such deep root in the imagina^ 
 tion, that 'tis impossible ever to eradicate it, nor will 
 any strain'd metaphysical conviction of the dependence 
 of our perceptions be sufficient for that purpose. 
 
 But tho' our natural and obvious principles here 
 prevail above our study'd reflections, 'tis certain there 
 must be some struggle and opposition in the case; at 
 least so long as these reflections retain any force or 
 vivacity. In order to set ourselves at ease in this par- 
 ticular, we contrive a new hypothesis, which seems to 
 comprehend both these principles of reason and imag- 
 ination. This hypothesis is the philosophical one of 
 the double existence of perceptions and objects; which 
 pleases our reason, in allowing, that our dependent 
 perceptions are interrupted and different; and at the 
 same time is agreeable to the imagination, in attribut- 
 ing a continu'd existence to something else, which we 
 call objects. This philosophical system, therefore, is 
 the monstrous offspring of two principles, which are 
 contrary to each other, which are both at once em- 
 brac'd by the mind, and which are unable mutually to 
 destroy each other. The imagination tells us, that our 
 resembling perceptions have a continu'd and uninter- 
 rupted existence, and are not annihilated by their_ab- 
 sence. Reflection tells us, that even our resembliflg 
 perceptions are interrupted in their existence, _aiid_difr 
 ferent from each other. The contradiction betwixt 
 these opinions we elude by a new fiction, which is con- 
 formable to the hypotheses both of reflection and 
 fancy, by ascribing these contrary qualities to dift'erent 
 existences ; the interruption to perceptions, and the 
 continuance to objects. Nature is obstinate, and will 
 not quit the field, however strongly attack'd by reason ; 
 
SECT. II BOOK I. OF THE UNDERSTANDING 241 
 
 and at the same time reason is so clear in the point, 
 that there is no possibiHty of disguising her. Not 
 being able to reconcile these two enemies, we endeavour 
 to set ourselves at ease as much as possible, by succes- 
 sively granting to each whatever it demands, and by 
 feigning a double existence, where each may find some- 
 thing, that has all the conditions it desires. Were we 
 fully convinc'd, that our resembling perceptions are 
 continu'd, and identical, and independent, we shou'd 
 never run into this opinion of a double existence ; since 
 we should find satisfaction in our first supposition, and 
 wou'd not look beyond. Again, were we fully con- 
 vinc'd, that our perceptions are dependent, and inter- 
 rupted, and dififerent, we shou'd be as little inclin'd to 
 embrace the opinion of a double existence; since in 
 that case we shou'd clearly perceive the error of our 
 first supposition of a continu'd existence, and wou'd 
 never regard it any farther. Tis therefore from the 
 intermediate situation of the mind, that this opinion 
 arises, and from such an adherence to these two con- 
 trary principles, as makes us seek some pretext to 
 justify our receiving both; which happily at last is 
 found in the system of a double existence. 
 
 Another advantage of this philosophical system is 
 its similarity to the vulgar one; by which means we 
 can humour our reason for a moment, when it becomes 
 troublesome and sollicitous ; and yet upon its least neg- 
 ligence or inattention, can easily return to our vulgar 
 and natural notions. Accordingly we find, that phil- 
 osophers neglect not this advantage; but immediately 
 upon leaving their closets, mingle with the rest of man- 
 kind in those exploded opinions, that our perceptions 
 are our only objects, and continue identically and unin- 
 
242 A TREATISE OF HUMAN NATURE PART IV 
 
 terruptedly the same in all their interrupted appear- 
 ances. 
 
 There are other particulars of this system, wherein 
 we may remark its dependence on the fancy, in a very 
 conspicuous manner. Of these, I shall observe the two 
 following. First, We suppose external objects to re- 
 semble internal perceptions. I have already shewn, 
 that the relation of cause and effect can never aft'ord 
 us any just conclusion from the existence or quali- 
 ties of our perceptions to the existence of external con- 
 tinu'd objects : And I shall farther add, that even tho' 
 they cou'd afford such a conclusion, we shou'd never 
 have any reason to infer, that our objects resemble our 
 perceptions. That opinion, therefore, is deriv'd from 
 nothing but the quality of the fancy above-explain'd_, 
 that it horrozvs all its ideas from some precedent perr 
 ception. We never can conceive any thing but percep- 
 tions, and therefore must make every thing resemble 
 them. 
 
 Secondly, As we suppose our objects in general to 
 resemble our perceptions, so we take it for granted, 
 that every particular object resembles that perception, 
 which it causes. The relation of cause and effect de- 
 termines us to join the other of resemblance; and the 
 ideas of these existences being already united together 
 in the fancy by the former relation, we naturally add 
 the latter to compleat the union. We have a strong 
 propensity to compleat every union by joining new 
 relations to those which we have before observ'd be- 
 twixt any ideas, as we shall have occasion to observe 
 presently .1 
 
 Having thus given an account of all the systems 
 both popular and philosophical, with regard to exter- 
 
 1 Sect. 5. 
 
SECT. II BOOK /. OF THE UNDERSTANDING 243 
 
 nal existences, I cannot forbear giving vent to a certain 
 sentiment, which arises upon reviewing those systems. 
 I begun this subject with premising, that we ought to 
 have an imphcit faith in our senses, and that this wou'd 
 be the conclusion, I shou'd draw from the whole of 
 my reasoning. But to be ingenuous, I feel myself at 
 present of a quite contrary sentiment, and am more 
 inclined to repose no faith at all in my senses, or rather 
 imagination, than to place in it such an implicit confi- 
 dence. I cannot conceive how such trivial qualities of 
 the fancy, conducted by such false suppositions, can 
 ever lead to any solid and rational system. They are 
 the coherence and constancy of our perceptions, which 
 produce the opinion of their continu'd existence; tho' 
 these qualities of perceptions have no perceivable con- 
 nexion with such an existence. The constancy of our 
 perceptions has the most considerable effect, and yet 
 is attended with the greatest difficulties. 'Tis a gross 
 illusion to suppose, that our resembling perceptions 
 are numerically the same; and 'tis this illusion, which 
 leads us into the opinion, that these perceptions are 
 uninterrupted, and are still existent, even when they 
 are not present to the senses. This is the case with 
 our popular system. And as to our philosophical one, 
 'tis liable to the same difficulties ; and is over-and-above 
 loaded with this absurdity, that it at once denies and 
 establishes the vulgar supposition. Philosophers deny 
 our resembling perceptions to be identically the same, 
 and uninterrupted ; and yet have so great a propensity 
 to believe them such, that they arbitrarily invent a new 
 set of perceptions, to which they attribute these qual- 
 ities. I say, a new set of perceptions: For we may 
 well suppose in general, but 'tis impossible for us dis- 
 tinctly to conceive, objects to be in their nature any 
 
244 A TREATISE OF HUMAN NATURE PART IV 
 
 thing but exactly the same with perceptions. What, 
 then can we look for from this confusion of ground- 
 less and extraordinary opinions but error and false- 
 hood? And how can we justify to ourselves any belief 
 we repose in them? 
 
 This sceptical doubt, both jwith respect to reason 
 and the senses, is a malady, which can never be radi-. 
 cally cur'd, but must return upon us every moment, 
 liowever we rnay chace it away, and sometimes may 
 seem entirely free from it. 'Tis impossible upon any 
 system to defend either our understanding or senses; 
 and we but expose them farther when we endeavour 
 to justify them in that manner. As the sceptical doubt 
 arises naturally from a profound and intense reflection 
 on those subjects, it always encreases, the farther we 
 carry our reflections, whether in opposition or con- 
 formity to it. Carelessness and in-attention alone can 
 aflford us any remedy. For this reason I rely entirely 
 upon them; and take it for granted, whatever may be 
 the reader's opinion at this present moment, that an 
 hour hence he will be persuaded there is both an 
 external and internal world ; and going upon that sup- 
 position, I intend to examine some general systems 
 both ancient and modern, which have been propos'd 
 of both, before I proceed to a more particular enquiry 
 concerning our impressions. This will not, perhaps, in 
 the end be found foreign to our present purpose. 
 
Section VI. 
 Of personal identity. 
 
 There are some philosophers, who imagine we are 
 every moment intimately conscious of what we call our 
 Self; that we feel its existence and its continuance 
 in existence; and are certain, beyond the evidence of 
 demonstration, both of its perfect identity and sim- 
 plicity. The strongest sensation, the most violent pas- 
 sion, say they, instead of distracting us from this view, 
 only fix it the more intensely, and make us consider 
 their influence on self either by their pain or pleasure. 
 To attempt a farther proof of this were to weaken its 
 evidence ; since no proof can be deriv'd from any fact, 
 of which we are so intimately conscious; nor is there 
 any thing, of which we can be certain, if we doubt 
 of this. 
 
 Unluckily all these positive assertions are contrary 
 to that very experience, which is pleaded for them, nor 
 have we any idea of self, after the manner it is here 
 explain'd. For from what impression cou'd this idea 
 be deriv'd? This question 'tis impossible to answer 
 without a manifest contradiction and absurdity; and 
 yet 'tis a question, which must necessarily be answer 'd, 
 if we wou'd have the idea of self pass for clear and 
 intelligible. It must be ,<;nmp nr|g ii npression, th at gives 
 r jse to eve ry r^al idff^ ,"Rn^ self or person is not any 
 one impression, but that to which our several impres- 
 sions and ideas are suppos'd to have a reference. If 
 any impression gives rise to the idea of self, that im- 
 
246 A TREATISE OF HUMAN NATURE PART IV 
 
 /pression must continue invariably the same, thro' the 
 whole course of our lives; since self is suppos'd to 
 exist after that manner. But there is no impression^ 
 •constant and invariable. Pain and pleasure, grief and 
 joy, passions and sensations succeed each other, and 
 never all exist at the same time. It cannot, therefore, 
 be from any of these impressions, or from any other, 
 that the i dea .of self is derived; and consequently there 
 _is_no such idea./ 
 
 But farther, what must become of all our particu- 
 lar perceptions upon this hypothesis? All these are 
 different, and distinguishable, and separable from each 
 other, and may be separately consider'd, and may exist 
 separately, and have no need of any thing to support 
 their existence. After what manner, therefore, do 
 they belong to self; and how are they connected with 
 it? For my part, when I enter most intimately into 
 what I call myself, I always stumble on some particu- 
 lar perception or other, of heat or cold, light or shade, 
 love or hatred, pain or pleasure. I never can catch 
 myself a t any time without a perception, and never 
 can observe any thing but the perception. When my 
 perceptions are remov'd for any time, as by sound 
 sleep ; so long am I insensible of mys£l^^,^and may truly 
 be said not to exist. And were all my p^ceptions. 
 remov'd by death, and cou'd I neither think, nor feel, 
 nor see, nor love, nor hate after the dissolution of my 
 body, I shou'd be entirely annihilated, nor do I con- 
 ceive what is farther requisite to make me a perfect 
 non-entity. If any one upon serious and unprejudic'd 
 reflexion, thinks he has a di fferent notion of Jii msdU- 
 I must confess I can reason no longer with him. All 
 I can allow him is, that he may be in the right as well 
 as I, and that we are essentially different in this par- 
 
SECT. VI BOOK I. OF THE UNDERSTANDING 247 
 
 ticular. He may, perhaps, perceive something simple 
 and continu'd, which he calls himself; tho' I am cer- 
 tain there is no such principle in me. 
 
 But setting aside some metaphysicians of this kind, 
 I may venture to affirm of the rest of mankind, that' 
 they are nothing but a b undle or collection of diff erent 
 perceptions, which succeed each other with an incon- 
 ceivable rapidity, and are in a perpetual flux and move- 
 ment. Our eyes cannot turn in their sockets without 
 varying our perceptions. Our thought is still more 
 variable than our sight; and all our other senses and 
 faculties contribute to this change; nor is there any 
 single power of the soul, which remains unalterably 
 the same, perhaps for one moment. The mind is a 
 kind of theatre, where several perceptions successively 
 make their appearance; pass, re-pass, glide away, and 
 mingle in an infinite variety of postures and situations. 
 There is properly no_j5'im^iid^3; in it ^t one time, nor 
 identity in different; whatever natural propension we 
 may have to imagine that simplicity and identity. 
 The comparison of the theatre must not mislead us. 
 They are the successive perceptions only, that con- 
 stitute the mind; nor have we the most distant notion 
 of the place, where these scenes are represented, or of 
 the materials, of which it is compos'd. 
 
 What then gives us so great a propension to ascribe 
 an identity to these successive perceptions, and to sup- 
 pose ourselves possest of an invariable and uninter- 
 rupted existence thro' the whole course of our lives? 
 In order to answer this question, we must distinguish 
 betwixt personal identity, as it regards our thought or 
 imagination, and as it regards our passions or the con- 
 cern we take in ourselves. The first is our present 
 subject; and to explain it perfectly we must take the 
 
 te 
 
248 A TREATISE OF HUMAN NATURE PART IV 
 
 matter pretty deep, and account for that identity, which 
 we attribute to plants and animals ; there being a great 
 analogy betwixt it, and the identity of a self or person. 
 We have a d istinct ide a of an^bi^ct, that remains 
 invariable and uninterrupted thro' a supposed varia- 
 tion of time; and this idea we call that of identity oj - 
 same n£ss^ We have also a distinct idea of several 
 different objects existing in succession, and connected 
 together by a close relation; and this to an accurate 
 view affords as perfect a notion of diversity, as if there 
 was no manner of relation among the objects. But 
 tho' these two ideas of identity, and a succession of 
 related objects be in themselves perfectly distinct, and 
 even contrary, yet 'tis certain, that in our common way 
 of thinking they are generally confounded with each 
 other. That action of the i magination, b y which we 
 consider the uninterrupted and mvariable object, and 
 that by which we reflect on the succession of related 
 objects, are almost the same to the feeling, nor is there 
 much more effort of thought requir'd in the latter case 
 than in the former. The relation facilitates the tran- 
 sition of the mind from one object to another, and 
 renders its passage as smooth as if it contemplated 
 one continu'd object. This resemblance is the cause 
 of the confusion and mistake, and makes us substitute 
 the notion of identity, instead of that of related objects . 
 However at one instant we may consider the related 
 succession as variable or interrupted, we are sure the 
 next to ascribe to it a perfect identity, and regard it 
 as invariable and uninterrupted. Our propensity to 
 this mistake is so great from the resemblance above- 
 mention'd, that we fall into it before we are aware; 
 and tho' we incessantly correct ourselves by reflexion, 
 and return to a more accurate method of thinking, 
 
SECT. VI BOOK I. OF THE UNDERSTANDING 249 
 
 yet we cannot long sustain our philosophy, or take off 
 this biass from the imagination. Our last resource 
 is to yield to it, and boldly assert that these different 
 related objects are in effect the same, however inter- 
 rupted and variable. In order to justify to ourselves 
 this absurdity, we often feign some new and unintel- 
 ligible principle, that connects the objects together, 
 and prevents their interruption or variation. Thus 
 we feign the continu'd existence of the perceptions of 
 our senses, to remove the interruption; and run into 
 the notion of a soul, and self, and substance, to dis- 
 guise the variation. But we may farther observe, that 
 where we do not give rise to such a fiction, our pro- 
 pension to confound identity with relation is so great, 
 that we are apt to imagine^ something unknown and 
 mysterious, connecting the parts, beside their relation ; 
 and this I take to be the case with regard to the iden- 
 tity we ascribe to plants and vegetables. And even 
 when this does not take place, we still feel a propen- 
 sity to confound these ideas, tho' we are not able fully 
 to satisfy ourselves in that particular, nor find any 
 thing invariable and uninterrupted to justify our no- 
 tion of identity. 
 
 Thus the controversy concerning identity is not 
 merely a dispute of words. For when we attribute 
 identity, in an improper sense, to variable or inter- 
 rupted objects, our mistake is not confin'd to the ex- 
 pression, but is commonly attended with a fiction, 
 either of something invariable and uninterrupted, or 
 
 1 If the reader is desirous to see how a great genius may be 
 influenc'd by these seemingly trivial principles of the imagination, 
 as well as the mere vulgar, let him read my Lord Shaftsbury's 
 reasonings concerning the uniting principle of the universe, and 
 the identity of plants and animals. See his Moralists: or, Philo- 
 sophical rhapsody* 
 
250 A TREATISE OF HUMAN NATURE PART IV 
 
 of something mysterious and inexplicable, or at least 
 with a propensity to such fictions. What will suffice 
 to prove this hypothesis to the satisfaction of every 
 fair enquirer, is to shew from daily experience and 
 observation, that the objects, which are variable or 
 interrupted, and yet are suppos'd to continue^ the^ 
 same, are such only as consist of a succession of parts, 
 connected together by rese mblance , co ntigui ty, or 
 causation. For as such a succession answers evidently 
 to our notion of diversity, it can only be by mistake 
 we ascribe to it an identity; and as the relation of 
 parts, which leads us into this mistake, is really noth- 
 ing but a quality, which produces an association of 
 ideas, and an easy transition of the imagination from 
 one to another, it can only be from the resemblance, 
 which this act of the mind bears to that, by which we 
 contemplate one continu'd object, that the error arises. 
 Our chief business, then, must be to prove, that all 
 objects, to which we ascribe identity, without observ- 
 ing their invariableness and uninterruptedness, are 
 suc h as con sist of a succession nf relate d object s. 
 
 In order to this, suppose any mass of matter, of 
 which the parts are contiguous and connected, to be 
 plac'd before us ; 'tis plain we must attribute a perfect 
 identity to this mass, provided all the parts continue 
 uninterruptedly and invariably the same, whatever mo- 
 tion or change of place we may observe either in the 
 whole or in any of the parts. But supposing some 
 very small or inconsiderable part to be added to the 
 mass, or substracted from it; tho' this absolutely 
 destroys the identity of the whole, strictly speaking; 
 yet as we seldom think so accurately, we scruple not 
 to pronounce a mass of matter the same, where we find 
 so trivial an alteration. The passage of the thought 
 
SECT. VI BOOK I. OF THE UNDERSTANDING 251 
 
 from the object before the change to the object after 
 it, is so smooth and easy, that we scarce perceive the 
 transition, and are apt to imagine, that 'tis nothing 
 but a continu'd survey of the same object. 
 
 There is a very remarkable circumstance, that at- 
 tends this experiment; which is, that tho' the change 
 of any considerable part in a mass of matter destroys 
 the identity of the whole, yet we must measure the 
 greatness of the part, not absolutely, but by itsj^r^z^ 
 portism-JjoJtho. whole. The addition or diminution of 
 a mountain wou'd not be sufficient to produce a di- 
 versity in a planet ; tho' the change of a very few inches 
 wou'd be able to destroy the identity of some bodies. 
 'Twill be impossible to account for this, but by reflect- 1 
 ing that objects operate upon the mind, and break or 
 interrupt the continuity of its actions not according 
 to their real greatness, but according to their pro- 
 I)ortion to each other: And therefore, since this inter- 
 ruption makes an object cease to appear the same, it 
 must be the uninterrupted progress of the thought, 
 which constitutes the imperfect identity. 
 
 This may be confirm'd by another phaenomenon. 
 A change in any considerable part of a body destroys 
 its identity ; but 'tis remarkable, that where the change 
 is produc'd gradually and insensibly we are less apt 
 to ascribe to it the^ame eltect.^ The reason can plainly 
 be no other, than that thej3iio4, in following the suc- 
 cessive changes of the body, feels an easy passage 
 from the surveying its condition in one moment to the 
 viewing of it in another, and at nn particular time 
 perceive s any interruption in its actions. From which 
 coj itinu'd per cegtion,^ ascribes a contin u'd existence^ 
 and identity to the obj( 
 
252 A TREATISE OF HUMAN NATURE PART IV 
 
 But whatever precaution we may use in introduc- 
 ing the changes gradually, and making them propor- 
 tionable to the whole, 'tis certain, that where the 
 changes are at last observ'd to become considerable, 
 we make a scruple of ascribing identity to such differ- 
 ent objects. There is, however, another artifice, by 
 which we may induce the imagination to advance a 
 step farther; and that is, by producing a reference of 
 the parts to each other, and a combination to some 
 ic nmrngn (>nij , or purpose. A ship, of which a consider- 
 able part has been chang'd by frequent reparations, 
 is still consider'd as the same; nor does the difference 
 of the materials hinder us from ascribing an identity 
 to it. The common end, in which the parts conspire, 
 is the same under all their variations, and affords an 
 easy transition of the imagination from one situation 
 of the body to another. 
 
 But this is still more remarkable, when we add a 
 sympathy of parts to their common en d, and suppose 
 that they bear to each other, the reciprocal relation 
 of cause and effect in all their actions and operations. 
 This is the case with all animals and vegetables ; where 
 not only the several parts have a reference to some 
 general purpose, but also a mutual dependence on, and 
 connexion with each other. The effect of so strong 
 a relation is, that tho' every one must allow, that in a 
 very few years both vegetables and animals endure a 
 total change, yet we still attribute identity to them, 
 while their form, size, and substance are entirely al- 
 ter'd. An oak, that grows from a small plant to a 
 large tree, is still the same oak; tho' there be not one 
 particle of matter, or figure of its parts the same. An 
 infant becomes a man, and is sometimes fat, sometimes 
 lean, without any change in his identity. 
 
SECT. VI BOOK I. OF THE UNDERSTANDING 253 
 
 We may also consider the two following phae- 
 nomena, which are remarkable in their kind. The first 
 is, that tho' we commonly be able to distinguish pretty 
 exactly betwixt numerical and specific identity, yet it 
 sometimes happens, that we confound them, and in our 
 thinking and reasoning employ the one for the other. 
 Thus a man, who hears a noise, that is frequently 
 interrupted and renew'd, says, it is still the same noise ; 
 tho' 'tis evident the sounds have only a specific iden- 
 tity or resemblance, and there is nothing numerically 
 the same, but the cause, which produc'd them. In 
 like manner it may be said without breach of the pro- 
 priety of language, that such a church, which was 
 formerly of brick, fell to ruin, and that the parish 
 rebuilt the same church of free-stone, and according 
 to modern architecture. Here neither the form nor 
 materials are the same, nor is there any thing common 
 to the two objects, but their relation to the inhabitants 
 of the parish; and yet this alone is sufficient to make 
 us denominate them the same. But we must observe, 
 that in these cases the first object is in a manner anni- 
 hilated before the second comes into existence; by 
 which means, we are never presented in any one point 
 of time with the idea of difference and multiplicity; 
 and for that reason are less scrupulous in calling them 
 the same. 
 
 Secondly, We may remark, that tho' in a succes- 
 sion of related objects, it be in a manner requisite, 
 that the change of parts be not sudden nor entire, in 
 order to preserve the identity, yet where the objects 
 are in their nature changeable and inconstant, we 
 admit of a more sudden transition, than wou'd other- 
 wise be consistent with that relation. Thus as the 
 nature of a river consists in the motion and change of 
 
254 ^ TREATISE OF HUMAN NATURE PART IV 
 
 parts; tho' in less than four and twenty hours these 
 be totally alter'd ; this hinders not the river from con- 
 tinuing the same during several ages. What is natu- 
 ral and essential to any thing is, in a manner, ex- 
 pected; and what is expected makes less impression, 
 and appears of less moment, than what is unusual and 
 extraordinary. A considerable change of the former 
 kind seems really less to the imagination, than the 
 most trivial alteration of the latter; and by breaking 
 less the continuity of the thought, has less influence 
 in destroying the identity. 
 
 We now proceed to explain the nature of personal 
 identity , which has become so great a question in 
 philosophy, especially of late years in England, where 
 all the abstruser sciences are study'd with a peculiar 
 ardour and application. And here 'tis evident, the 
 same method of reasoning must be continu'd, which 
 has so successfully explain'd the identity of plants, 
 and animals, and ships, and houses, and of all the com- 
 pounded and changeable productions either of art or 
 nature. The identity, which we ascribe^ to ^he^minj 
 of man, is onlv a^c titious one, and of a like kind 
 with that which we ascribe to vegetables and apimal 
 bodies. It cannot, therefore, have a different origin, 
 but must proceed from a like operation of the imag- 
 ination upon like objects. 
 
 But lest this argument shou'd not convince the 
 reader; tho' in my opinion perfectly decisive; let him 
 weigh the following reasoning, which is still closer 
 and more immediate. 'Tis evident, that the identity, 
 which we attribute to the human mind, however per- 
 fect we may imagine it to be, is not able to run the 
 several different perceptions into one, and make them 
 lose their characters of distinction and difference, 
 
SECT. VI BOOK I. OF THE UNDERSTANDING 255 
 
 which are essential to them. Tis still true, that every, 
 distinct perceptio n, which enters into the composition 
 of the mind, is a distinct existence, and is different, 
 and distinguishableTand " separabl e" from j^very other 
 perception, either contemporary or successive. But, 
 as, notwithstanding this distinction and separability, 
 we suppose the whole train of perceptions to be united 
 by identity, a question naturally arises concerning this 
 relation of identity ; whether it be something that really 
 binds our several perceptions together, or only associates 
 their ideas in the imagination. That is, in other words, 
 whettipr in pronouncing concerning the identity of a 
 person, we observe some real bond among his, per cep-^ 
 ,tions#»or only feel one among the ideas we form of 
 them. This question we might "Easily decide, "li we 
 wou'd recollect what has been already prov'd at large, 
 that the understanding never observes any real con- 
 nexion among objects, and that even the union of 
 cause and effect, when strictly examin'd, resolves itself 
 into a customary association of ideas. For from thence 
 it evidently follows, that identity is nothing_really. hfic^ 
 longing to these different perceptions, and uniting^ 
 fhem together ; but is merely aquality, which we attri- > 
 bute to them, because of the unio n oT^ their ideas in the ^ 
 i magination , when we reflect upon them. Now the 
 only qualities, which can give ideas an union in the 
 imagination, are these three relations above-mentibn^dT 
 These are the uniti ng principles in the ideal world, 
 and without them every distinct object is separable 
 by the mind, and may be separately consider'd, and 
 appears not to have any more connexion with any 
 other object, than if disjoined by the greatest differ- 
 ence and remoteness. 'Tis therefore, on some of these 
 three relations of re semblan ce, contiguity and caus- 
 
2S6 A TREATISE OF HUMAN NATURE PART IV 
 
 ation, that identity depends; and as the very essence 
 of these relations consists in their producing an easy 
 transition of ideas; it follows, that our noti ons of per - 
 sonal identity , proceed entirely from the smooth and 
 uninterrupted progress of the thought along a train of 
 con nected ideas. ,^ according to the^ principles above- 
 e xplained. 
 
 The only question, therefore, which remains, is, by 
 what relations t his uninterrupted progress of our 
 thought^is^produc'd, when we consider the successive 
 existence of a mind or thinking person. And here' tis 
 evident we must confine ourselves to resembl^Cfie 3.nd 
 causation . and must drop contiguity, which has little 
 or no influence in the present case. 
 
 To begin with resemblance; suppose we cou'd see 
 clearly into the breast of another, and observe that 
 succession of perceptions, which constitutes his mind 
 or thinking principle, and suppose that he always pre- 
 serves the memory of a considerable part of past per- 
 ceptions; 'tis evident that nothing cou'd more con- 
 tribute to the bestowing a relation on this succession 
 amidst all its variations. For what is the memory but 
 a faculty, by whjfh we raise up the images of past 
 perceptions? And as an image necessarily resembles 
 its object, must not the frequent placing of these 
 resembling perceptions in the chain of thought, con- 
 vey the imagination more easily from one link to 
 another, and make the whole seem like the continu- 
 ance of one object? In this particular, then, the mem- 
 ory not only rJiscnvers th^ identity, but also contributes 
 to its production, by producing the r elation of resem- 
 blance among the perceptions. The case is the same 
 whether we consider ourselves or others. 
 
SECT. VI BOOK I. OF THE UNDERSTANDING 257 
 
 As to causation; we may observe, that the true 
 idea of the h uman min d, is to consider it as a system 
 of diff erent perceptio ns or differente xisten^ s. which 
 are link'd together by the relation of cause andeffect, 
 and mutually produce, destroy, influence, and modify 
 each other. Our impressions give rise to their cor- 
 respondent ideas; and these ideas in their turn pro- 
 duce other impressions. One thought chaces another, 
 and draws after it a third, by which it is expell'd in 
 its turn. In this respect, I cannot compare the soul 
 more properly to any thing than to a republic or com- 
 monwealth, in which the several members are united 
 by the reciprocal ties of government and subordina- 
 tion, and give rise to other persons, who propagate 
 the same republic in the incessant changes of its parts. 
 And as the same individual republic may not only 
 change its members, but also its laws and constitu- 
 tions; in like manner the same person may vary his 
 character and disposition, as well as his impressions 
 and ideas, without losing his identity. Whatever 
 changes he endures, hisseyeral— paj^s are still co^ 
 nected by the relat ion orcausati on. And in this view 
 "our identity with regard to the passions serves to cor- 
 roborate that with regard to the imagination, by the 
 making our distant perceptions influence each other, 
 and by giving us a present concern for our past or 
 future pains or pleasures. 
 
 As memory alone acquai nts us with the continu- 
 ance and extent of this s uccession of perceptions, 'tis 
 to be consider'd, upon that account chiefly, as the 
 source of ^^e£sonalJil£ilUty. Had we no memory, we 
 never shou'd have any notion of causation , nor con- 
 sequently of that chain of cau ses and effects, which 
 cons titute our self or person. But having once acquir'd 
 
258 A TREATISE OF HUMAN NATURE PART IV 
 
 this notion of causation from the memory, we can 
 extend the same chain of causes, and consequently the 
 identity of our persons beyond our memory, and can 
 comprehend times, and circurhstances, and actions, 
 which we have entirely forgot, but suppose in general 
 to have existed. For how few of our past actions 
 are there, of which we have any memory? Who can 
 tell me, for instance, what were his thoughts and 
 actions on the first of January 171 5, the nth of March 
 1719, and the 3d of August 1733? Or will he affirm 
 because he has entirely forgot the incidents of these 
 days, that the present self is not the same person with 
 the self of that time; and by that means overturn all 
 the most establish'd notions of personal identity? In 
 this view, therefore, memQry does not so much p roduce^ 
 as disco ver personal identit y, by shewing us the r ela-_ 
 tion ot cause and eff ect among our different percep- 
 tions. 'Twill be incumbent on those, who affirm that 
 memory produces entirely our personal identity, to 
 give a reason why we can thus extend our identity 
 beyond our memory. 
 
 The whole of this doctrine leads us to a conclu- 
 sion, which is of great importance in the present affair, 
 viz. that all the nice and subtile questions concerning 
 personal identity can never possibly be decided, and 
 are to be regarded rather as grammatical than as phil- 
 osophical difficulties. Identity ^depends on ^thfi-idar 
 tion of ideas; and these relations produce identity, by 
 means of that easy transition they occasion. But as 
 the relations, and the easiness of the transition may 
 diminish by insensible degrees, we have no just stand- 
 ard, by which we can decide any dispute concerning 
 the time, when they acquire or lose a title to the name 
 of identity. All the disputes concerning the identity 
 
SECT. VI BOOK I. OF THE UNDERSTANDING 259 
 
 of connected objects are merely verbal, except so far 
 as the relation of parts gives rise to some fiction or 
 imaginary principle of union, as we have already 
 observed. 
 
 What I have said concerning the first origin and 
 uncertainty of our notion of identity, as apply'd to the 
 human mind, may be extended with little or no varia- 
 tion to that of .^plidty. An object, whose different 
 co-existent parts are bound, together by a close rela- 
 tion, operates upon the imagination after much the 
 same manner as one perfectly simple and indivisible, 
 and requires not a much greater stretch of thought in 
 order to its conception. From this similarity of opera- 
 tion we attribute a simplicity to it, and feign a prin- 
 ciple of union as the support of this simplicity, and 
 the center of all the different parts and qualities of 
 the object. 
 
 Thus we have finish'd our examination of the sev- 
 eral systems of philosophy, both of the intellectual and 
 moral world ; and in our miscellaneous way of reason- 
 ing have been led into several topics ; which will either 
 illustrate and confirm some preceding part of this dis- 
 course, or prepare the way for our following opinions. 
 'Tis now time to return to a more close examination 
 of our subject, and to proceed in the accurate anatomy 
 of human nature, having fully explained the nature 
 of our judgment and understanding. 
 
 ^ ^ ^ ^ ^ 
 
 4( 4: 4c * * 4$ 
 
APPENDIX. 
 ****** 
 
 I had entertain'd some hopes, that however de- 
 ficient our theory of the intellectual world might be, 
 it wou'd be free from those contradictions, and absurd- 
 ities, which seem to attend every explication, that hu- 
 man reason can give of the material world. But upon 
 a more strict review of the section concerning personal 
 identity, I find myself involv'd in such a labyrinth, 
 that, I must confess, I neither know how to correct 
 my former opinions, nor how to render them consis- 
 tent. If this be not a good general reason for scep- 
 ticism, 'tis at least a sufficient one (if I were not 
 already abundantly supplied) for me to entertain a 
 diffidence and modesty in all my decisions. I shall 
 propose the arguments on both sides, beginning with 
 those that induc'd me to. deny the strict and proper 
 identity and simplicity of a self or thinking being. . 
 
 When we talk of self or substance, we must have 
 an idea annex'd to these terms, otherwise they are 
 altogether unintelligible. Every idea is deriv'd from 
 preceding impressions; and we have no impression of 
 self or substance, as something simple and individual. 
 We have, therefore, no idea of them in that sense. 
 
 Whatever is distinct, is distinguishable; and what- 
 ever is distinguishable, is separable by the thought or 
 imagination. All perceptions are distinct. They are, 
 therefore, distinguishable, and separable, and may be 
 conceiv'd as separately existent, and may exist s^epa- 
 rately, without any contradiction or absurdity. 
 
APPENDIX 261 
 
 When I view this table and that chimney, nothing 
 is present to me but particular perceptions, which are 
 of a Hke nature with all the other perceptions. This is 
 the doctrine of philosophers. But this table, which is 
 present to me, and that chimney, may and do exist 
 separately. This is the doctrine of the vulgar, and 
 implies no contradiction. There is no contradiction, 
 therefore, in extending the same doctrine to all the 
 perceptions. 
 
 In general, the following reasoning seems satis- 
 factory. All ideas are borrow'd from preceding per- 
 ceptions. Our ideas of objects, therefore, are deriv'd 
 from that source. Consequently no proposition can 
 be intelligible or consistent with regard to objects, 
 'which is not so with regard to perceptions. But 'tis 
 intelligible and consistent to say, that objects exist 
 distinct and independent, without any common simple 
 substance or subject of inhesion. This proposition, 
 therefore, can never be absurd with regard to percep- 
 tions. 
 
 When I turn my reflexion on myself, I never can, 
 perceive this .y^// jwith^ut some one or more percep- / 
 tions ; nor can I ever perceive any thing but the percep- > 
 tions. 'Tis the composition of these, therefore, which '^ 
 forms the self. 
 
 We can conceive a thinking being to have either 
 many or few perceptions. Suppose the mind to be 
 reduced even below the life of an oyster. Suppose it 
 to have only one perception, as of thirst or hunger. 
 Consider it in that situation. Do you conceive any 
 thing but merely that perception? Have you any no- 
 tion of self or substance? If not, the addition of other 
 perceptions can never give you that notion. 
 
262 A TREATISE OF HUMAN MATURE 
 
 The annihilation, which some people suppose to 
 follow upon death, and which entirely destroys this 
 self, is nothing but an extinction of all particular per- 
 ceptions; love and hatred, pain and pleasure, thought 
 and sensation. These therefore must be the same with 
 self; since the one cannot survive the other. 
 
 Is self the same with substance f If it be, how can 
 that question have place, concerning the subsistence of 
 self, under a change of substance ? If they be distinct, 
 what is the difference betwixt them? For my part, 
 I have a notion of neither, when conceiv'd distinct 
 from particular perceptions. 
 
 Philosophers begin to be reconcil'd to the principle, 
 that we have no idea of external substanc e , distinct 
 from the ideas of particular qualities. This must pave 
 the way for a like principle with regard to the mind, 
 that we have no notion of it, distinct from the par- 
 ticular perceptions. 
 
 So far I seem to be attended with sufficient evi- 
 dence. But having thus loosen'd all our particular 
 perceptions, when^ I proceed to explain the principle 
 of connexion, which binds them together, and makes 
 us attribute to them a real simplicity and identity; I 
 am sensible, that my account is very defective, and 
 that nothing but the seeming evidence of the precedent 
 reasonings cou'd have induc'd me to receive it. If 
 perceptions are distinct existences, they form a whole 
 only by being connected together. But no connexions 
 among distinct existences are ever discoverable by 
 human understanding. We only feel a connexion or 
 determination of the thought, to pass from one object 
 to another. It follows, therefore, that the thought_ 
 alone finds personal identity, when reflecting., o n the . 
 train of past perceptions, that co mpose a mind, the 
 
APPENDIX 263 
 
 ideas of them are felt to be connected together, and 
 naturally introduce each other. However extraordin- 
 ary this conclusion may seem, it need not surprize us. 
 Most philosophers seem inclin'd to think, that per- 
 sonal identity arises from consciousness; and con- 
 sciousness is nothing but a reflected thought or per- 
 ception. The present philosophy, therefore, has so far 
 a promising aspect. But all my hopes vanish, when I 
 come to explain the principles, that unite our success- 
 ive perceptions in our thought or consciousness. I 
 cannot discover any theory, which gives me satisfac- 
 tion on this head. 
 
 In short jtliere are two principles, which J...camiQt^ 
 "render consistent ; nor is it in niy_ pow^r_ to^renouace, 
 either of them, viz. that all our distinct perceptions ars 
 distinct existences, and that the mind never perceives 
 any real connexion among distinct existences. Did 
 our perceptions either inhere in something simple and 
 individual, or did the mind perceive some real connex- 
 ion among them, there wou'd be no difficulty in the 
 case. For my part, I must plead the privilege of a 
 sceptic, and confess, that this difficulty is too hard for 
 my understanding. I pretend not, however, to pro- 
 nounce it absolutely insuperable. Others, perhaps, or 
 myself, upon more mature reflexions, may discover 
 some hypothesis, that will reconcile those contradic- 
 tions. 
 
INDEX 
 
 Abstraction, 164. 
 
 Abstract sciences, 167, 173. 
 
 Academic philosophy, 41 et seq. 
 
 Accuracy, 6. 
 
 Addison, 3. 
 
 Alchemy, 136. 
 
 Alexander, 87. 
 
 Alexander, the false prophet, 126. 
 
 Algebra, 187. 
 
 Ambiguous expressions, 83. 
 
 Analogy, reasoning by, 109. 
 
 Animals, reason of, 109 et seq. 
 
 Annihilation, 22, 
 
 A priori, 25, 26, 34, 44. 
 
 Aqua regia, 228. 
 
 Arguments, demonstrative, 57; 
 probable, 57; mutual destruc- 
 tion of, 121. 
 
 Arithmetic, 187. 
 
 Aristotle, 3, 86. 
 
 Association of ideas, 21 et seq., 
 SI et seq., 255. 
 
 Assurance, degrees of, 115. 
 
 Astronomy, 175. 
 
 Atheists, 159. 
 
 Athens, 139, 141. 
 
 Aurelius, Marcus, 126. 
 
 Bacon, 136. 
 
 Bayle, 164. 
 
 Bede, 132. 
 
 Belief, 47 et seq., 50 et seq., 60, 
 
 112, 196. 
 Berkeley, 164. 
 Bible, 137. 
 
 Billiard-ball, 2y, 48, 64, 72, 78, 81. 
 Bodies, operation of, j6, 84 et 
 
 seq., 95. 
 Body, existence of, 232 et seq. 
 
 Caesar, 174. 
 Cartesians, 207 et seq. 
 
 Cartesian doubt, 159. 
 Catastrophes, 135. 
 
 Cato, 119. 
 
 Causation, jy et seq., 185 et seq., 
 257. 
 
 Cause and effect, 22 et seq., 42 et 
 seq,. 84 et seq., 143 et seq., 
 169, 198, et seq., 255. 
 
 Causes, ultimate, 29 et seq.; simi- 
 lar, 35 et seq.; final, 56; prob- 
 ability of, 58; invisible, 71; oc- 
 casional, y2; definition, 219. 
 
 Chance, 57 et seq., 99, 221. 
 
 Chemistry, 175. 
 
 Child, burnt, 38. 
 
 Christian religion, 114, 137, 138. 
 
 Chronology, 175. 
 
 Cicero, 3, 53, 124. 
 
 Clarke, 76, 199. 
 
 Climates, 59. 
 
 Color-sensation, i8.- 
 
 Conduct, human, determinism and 
 liberty in, 85 et seq. 
 
 Conjecture, 154. 
 
 Conjunction, 72 et seq., 76 et seq., 
 85, 169; customary, 47, 50; con- 
 stant, 96, 231. 
 
 Connexion, 25 et seq., 32, 36, 51 
 et seq., 72 et seq.; necessary, 
 61 et seq., 64, 76 et seq., 99. 
 196, 202 et seq. 
 
 Constraint, 100. 
 
 Contiguity, 22 et seq., 53 et seq., 
 192, et seq. 
 
 Continued existence of objects, 
 2^2 et seq. 
 
 Contrariety, 22, 185. 
 
 Contrast, 22. 
 
 Copies of impressions, ideas, 16 
 et seq., 63 et seq., 80, 189, 208, 
 211, 222, 227. 
 
INDEX 
 
 26s 
 
 Creator, responsibility of, 104. 
 Criticism, 175. 
 Cudworth, 76. 
 Curtius, Quintus, 87. 
 Custom, 43 et seq., 55, 112. 
 Customary, connexion, 80 et seq.; 
 transition, 79 et seq., 95. 
 
 Definitions, exact, 82. 
 
 Deity, 207 et seq. 
 
 Demetrius, 129. 
 
 Demonstration, proper objects of, 
 
 ^73- 
 Demonstrative, arguments, 57; 
 
 reasoning, 34. 
 Demosthenes, 124. 
 Descartes, 76, 158. 
 Design, 151, 
 Determination of the mind, 203, 
 
 213 et seq. 
 Determinism, 83 et seq. 
 Distance, 235. 
 Distinctness, 231 et seq., 260 et 
 
 seq. 
 Divine existence, argument for, 
 
 143- 
 Divinity, 175. 
 Divisibility, infinite, 166. 
 Doubt, Cartesian, 159. 
 Dreams, 1 62. 
 
 I>ye, 57. 
 
 Effect. See Cause. 
 
 Elizabeth, Queen, 135. 
 
 Eloquence, 124. 
 
 End, common, 252. 
 
 Endeavour, 69. 
 
 Energy, 63, 80; of causes, 205 
 See Force. 
 
 Epicurus, 139 et seq., 141 et seq., 
 IS5, 170- 
 
 Ethics, 148 et seq. 
 
 Euclid, 23, 62. 
 
 Evidence, 24; natural, 93 et seq.; 
 for the truth of Christian re- 
 ligion, 114; contrariety of, 118; 
 of sense, 160 et seq.; objections 
 to moral, 168 et seq. 
 
 Evil, 105 et seq. 
 
 Existence, idea of, 229 et seq.; 
 continued, of objects, 2^2 et 
 
 seq.; distinct, of objects, 233 et 
 seq. 
 
 Experience, 26 et seq., 134, 162, 
 174; foundation of conclusions 
 from, 31 et seq.; reasonings 
 from, 35, 41; inferences from, 
 44; the foundation of evidence, 
 115 et seq., 186 et seq., 201. 
 
 Experiments, 116, 235. 
 
 Extension, idea of, 164. 
 
 External objects, belief of, 161 et 
 seq. 
 
 Extraordinary, the, 118 et seq. 
 
 Fact, matters of, 23 et seq. 
 
 Faith, 137, 138. 
 
 Fiction, 48. 
 
 Final causes, 56. 
 
 Force, 63, 80, 204 et seq., sop 
 
 et seq., 231. 
 Free will, 83 et seq. 
 Future state, 139 et seq. 
 
 Gabriel, 174. 
 
 General ideas, 164, 168, 209. 
 Geography, 175; mental, 10. 
 Geometry, 29, 61, 168, 187. 
 God, 73, 74, 104, 107, 136, 153, 
 
 156, 163. 
 Gods, the, 144 et seq. 
 Gravity, 59. 
 
 Habit, 43 et seq. 
 
 Harmony, pre-established, 55. 
 
 Heredotus, 132. 
 
 Hippocrates, 86. 
 
 History, 93, 175. 
 
 Hobbes, 1 98. 
 
 Human body, 90. 
 
 Human nature, science of, i et 
 
 seq.; principles and operations 
 
 of, 85 et seq. 
 Human mind, 254. 
 Hypothesis, 149. 
 
 Ideas, origin of, 14 et seq.; asso- 
 ciation of, 21 et seq.; relations 
 of, 2$ et seq.; complex, 63; 
 copies of our impressions, 63 et 
 seq., 80, 189, 208, 211, 222, 227, 
 general, 164, 168. 
 
266 
 
 INDEX 
 
 Identity, 185, 190. 
 Identity, personal, 245 et seq. 
 Identity, of objects, 250 et seq. 
 Images, sensible, 52. 
 Imagination, 47 et seq., 49, 172, 
 
 234 et seq. 
 Impostures, 126. 
 Impressions, 15 et seq.; original, 
 
 63; of power, 213. 
 Indeterminism, 83 et seq. 
 Indian prince, 119. 
 Infinite divisibility, 166. 
 Innate, 19; ideas, 208. 
 Instincts, 113. 
 Invisible causes, 71. 
 
 Jansenist miracles, 131. 
 Jesuits, 131. 
 Jupiter^. 145, 146. 
 Justice, distributive, 149. 
 
 La Bruyere, 3. 
 
 Liberty, 83 et seq.; defined, 99. 
 
 Limbs, use of our, 56. 
 
 Livy, 128, 136. 
 
 Locke, 4, 20, 57, 65, 76, 200, 204. 
 
 Lucian, 126, 139, 140. 
 
 Lucretius, 132. 
 
 Magic, 136. 
 
 Mahomet, 128. 
 
 Malebranche, 3, 76, 205. 
 
 Mankind, the same in all times 
 and places, 86 et seq. 
 
 Mariana, 132. 
 
 Marvellous, the, 118 et seq.; pro- 
 pensity to the, 124 et seq. 
 
 Mathematics, 23, 30, 61, 174, 187. 
 
 Matters of fact, 23 et seq., 176. 
 
 Medicine, 90. 
 
 Mental, geography, 10; research, 
 II. 
 
 Metaphysics, 5 et seq., 62, 176. 
 
 Mind, command of, over the body, 
 70. 
 
 Miracles, 114 et seq.; defined, 
 121; reasons for discrediting, 
 122 et seq. 
 
 Mode, 227 et seq. 
 
 Moral evidence, 93 et seq.; objec- 
 tions to, 168 et seq. 
 
 Morality, doctrines of necessity 
 and of liberty consistent with, 
 100. 
 
 Moral, philosophy, i et seq.; rea- 
 soning, 34, 175. 
 
 Morals, 93, 175. 
 
 Motion, 27. 
 
 Motives and voluntary actions, 
 conjunction between, 85 et seq. 
 
 Muscovy, 119. 
 
 Myself. See Self. 
 
 Natural evidence, 93 et seq. 
 
 Natural philosophy, 175. 
 
 Nature, course of, 150; violatio/is 
 
 of the course of, 134. 
 Necessary connexion, 64, 196, 2^2 
 
 et seq. 
 Necessity, 83 et seq., 98 et sec^ ; 
 
 as an inference, 85; defintil, 
 
 100, 197 et seq., 216; in H.q 
 
 mind, 214. 
 Newton, 75. 
 Number, 173, 176, 185 et seq. 
 
 Occasions, 72 et seq. 
 Objects, sensible, 52, 232 et seq ; 
 external, 242. 
 
 Paphlagonia, 126. 
 Paris, Abbe, 131. 
 Pentateuch, 137. 
 Perceptions, 14. 
 Pharsalia, battle of, 131. 
 Philippi, battle of, 131. 
 Philosophers, fame of, 3. 
 Philosophy, 139 et seq.; nature of, 
 
 I et seq.; natural, 175. 
 Physic, 175. 
 Plutarch, 128, 132. 
 Points, mathematical, 166. 
 Politics, 93. 
 Polybius, 86. 
 Possibility, 149. 
 Power, 63, 64, 68 et seq., 80, 204 
 
 et seq.; impression of, 213. See 
 
 Force. 
 Pre-established harmony, 55. 
 Pre-ordination, 103. 
 Priority, 193. 
 
INDEX 
 
 267 
 
 Probability, 57 et seq., 116 et seq,, 
 120, 134- 
 
 Prodigies, reasons for discredit- 
 ing, 122 et seq. 
 
 Proofs, 57, 116 et seq., 120, 134. 
 
 Propliecies, 138. 
 
 Prophet, Alexander the false, 126. 
 
 Protagoras, 139. 
 
 Providence, a particular, 139 et 
 seq.; divine, 148. 
 
 Public good, questions of, 142. 
 
 Punishments, loi. 
 
 Purpose, 252, 
 
 Pyrrhonism, 168, 170, 172. 
 
 Qualities, sensible, 65; secondary 
 
 and primary, 164. 
 Quantity, 173, 176; science of, 
 
 168. 
 
 Reason, 26 et seq.; of animals, 
 109 et seq.; attempt to destroy, 
 165, 234 et seq. 
 
 Reasoning, two kinds of, 34; con- 
 cerning matter of fact, nature 
 of, 31 et seq.; d priori, 34; 
 
 ' demonstrative, 34; moral, 34, 
 62, 175; from experience, 41; 
 comparison, 190. 
 
 Regular succession, 56. 
 
 Relations of ideas, 23 et seq. 
 
 Relations, philosophical, 185, 219. 
 
 Religion, 123, 127. 
 
 Religious doctrines and life, 155. 
 
 Resemblance, 22 et seq.; 51 et 
 seq., 185, 256. 
 
 Retz, Cardinal de, 130. 
 
 Rewards, loi. 
 
 Roman Catholic religion, 52. 
 
 Roman emperors, 140. 
 
 Saragossa, miracle of, 130. 
 Sceptical philosophy, 41 et seq., 
 
 158 et seq., 244. 
 Scepticism, mitigated, 171; with 
 
 regard to senses, 232 et seq. 
 Science, proper subjects of, 173. 
 Sciences, abstract, 167, 173. 
 Self, idea of, 245 et seq., 260 et 
 
 seq. 
 
 Senses, 32; evidence of, 160 et 
 seq.; perceptions of the, 162 et 
 seq. 
 
 Sensible, images, 52; objects, 52; 
 qualities, 65. 
 
 Serapis, 129. 
 
 Shaftsbury, Lord, 349. 
 
 Similar, causes, 35 et seq.; effects, 
 35 et seq.; instances, 81; ob- 
 jects, 61, 79. 
 
 Simplicity of mind, 247. 
 
 Socrates, 139. 
 
 Soul, 249. 
 
 Soul with body, union of, 66 et 
 seq. 
 
 Space, ideas of, 165 et seq. 
 
 Stoics, 40, 105, 170. 
 
 Substance, 227, 249, 260. 
 
 Succession, regular, 56. 
 
 Suetonius, 129. 
 
 Sumatra, 119. 
 
 Supreme Being, 208. 
 
 Surprise, 123 et seq. 
 
 Tacitus, 86, 128. 
 
 Terms, meaning of, 82. 
 
 Testimony, human, 116 et seq.; 
 circumstances requisite to give 
 full assurance to, 122. 
 
 Theology, 175. 
 
 Thoughts, IS et seq. 
 
 Tillotson, Dr., 114. 
 
 Time, ideas of, 165 et seq.; re- 
 lations of, 185. 
 
 Transition of the mind, 220. 
 
 Truth, criteria of, 160. 
 
 Ultimate causes, 29 et seq. 
 Uniformity in nature, 84 et seq., 
 87 et seq. 
 
 Velleity, 98. 
 
 Vespasian, 128. 
 
 Vis inertiae, 75. 
 
 Volition, 66 et seq., 83 et seq. 
 
 Will, 66 et seq., 83 et seq. 
 Witnesses, 118. 
 Wonder, 123 et seq. 
 
 Zeuxis, 144. 
 
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