1911 Encyclopædia Britannica/Hume, David
DAVID HUME (1711–1776), English philosopher, historian and political economist, was born at Edinburgh, on the 26th of April (O.S.) 1711. His father, Joseph Hume or Home, a scion of the noble house of Home of Douglas (but see Notes and Queries, 4th ser. iv. 72), was owner of a small estate in Berwickshire, on the banks of the Whiteadder, called, from the spring rising in front of the dwelling-house, Ninewells. David was the youngest of a family of three, two sons and a daughter, who after the early death of the father were brought up with great care and devotion by their mother, the daughter of Sir David Falconer, president of the college of justice.
Of Hume's early education little is known beyond what he has himself stated in his Life. He appears to have entered the Greek classes of the university of Edinburgh in 1723, and, he tells us, " passed through the ordinary course of education with success." From a letter printed in Burton's Life (i. 30-39), it appears that about 1726 Hume returned to Ninewells with a fair knowledge of Latin, slight acquaintance with Greek and literary tastes decidedly inclining to " books of reasoning and philosophy, and to poetry and the polite authors." We do not know, except by inference, to what studies he especially devoted himself. It is, however, clear that from his earliest years he began to speculate upon the nature of knowledge in the abstract, and its concrete applications, as in theology, and that with this object he studied largely the writings of Cicero and Seneca and recent English philosophers (especially Locke, Berkeley and Butler). His acquaintance with Cicero is clearly proved by the form in which he cast some of the most important of his speculations. From his boyhood he devoted himself to acquiring a literary reputation, and throughout his life, in spite of financial and other difficulties, he adhered to his original intention. A man of placid and even phlegmatic temperament, he lived moderately in all things, and sought worldly prosperity only so far as was necessary to give him leisure for his literary work. At first he tried law, but was unable to give his mind to a study which appeared to him to be merely a barren waste of technical jargon. At this time the intensity of his intellectual activity in the area opened up to him by Locke and Berkeley reduced him to a state of physical exhaustion. In these circumstances he determined to try the effect of complete change of scene and occupation, and in 1734 entered a business house in Bristol. In a few months he found " the scene wholly unsuitable " to him, and about the middle of 1734 set out for France, resolved to spend some years in quiet study. He visited Paris, resided for a time at Rheims and then settled at La Fleche, famous in the history of philosophy as the school of Descartes. His health seems to have been perfectly restored, and during the three years of his stay in France his speculations were worked into systematic form in the Treatise of Human Nature. In the autumn of 1737 he was in London arranging for its publication and polishing it in preparation for the judgments of the learned. In January 1739 appeared the first and second volumes of the Treatise of Human Nature, being an Attempt to Introduce the Experimental Method of Reasoning into Moral Subjects, containing book i., Of the Understanding, and book ii., Of the Passions. The third volume, containing book iii., Of Morals, was published in the following year. The publisher of the first two volumes, John Noone, gave him -£50 and twelve bound copies for a first edition of one thousand copies. Hume's own words best describe its reception. " Never literary attempt was more unfortunate; it fell dead-born from the press, without reaching such distinction as even to excite a murmur among the zealots." " But," he adds, " being naturally of a cheerful and sanguine temper, I very soon recovered the blow, and prosecuted with great ardour my studies in the country." This brief notice, however, is not sufficient to explain the full significance of the event for Hume's own life. The work undoubtedly failed to do what its author expected from it; even the notice, otherwise not unsatisfactory, which it obtained in the History of the Works of the Learned, then the principal critical journal, did not in the least appreciate the true bearing of the Treatise on current discussions. Hume naturally expected that the world would see as clearly as he did the connexion between the concrete problems agitating contemporary thought and the abstract principles on which their solution depended. Accordingly he looked for opposition, and expected that, if his principles were received, a change in general conceptions of things would ensue. His disappointment at its reception was great; and though he never entirely relinquished his metaphysical speculations, though all that is of value in his later writings depends on the acute analysis of human nature to which he was from the first attracted, one cannot but regret that his high powers were henceforth withdrawn for the most part from the consideration, of the foundations of belief, and expended on its practical applications. In later years he attributed his want of success to the immature style of his early exposition, to the rashness of a young innovator in an old and well-established province of literature. But this has little foundation beyond the irritation of an author at his own failure to attract such attention as he deems his due. None of the principles of the Treatise is given up in the later writings, and no addition is made to them. Nor can the superior polish of the more mature productions counterbalance the concentrated vigour of the more youthful work.
After the publication of the Treatise Hume retired to his brother's house at Ninewells and carried on his studies, mainly in the direction of politics and political economy. In 1741 he published the first volume of his Essays, which had a considerable and immediate success. A second edition was called for in the following year, in which also a second volume was published. These essays Butler, to whom he had sent a copy of his Treatise, but with whom he had failed to make personal acquaintance, warmly commended. The philosophical relation between Butler and Hume is curious. So far as analysis of knowledge is concerned they are in harmony, and Hume's sceptical conclusions regarding belief in matters of fact are the foundations on which Butler's defence of religion rests. Butler, however, retained, in spite of his destructive theory of knowledge, confidence in the rational proofs for the existence of God, and certainly maintains what may be vaguely described as an a priori view of conscience. Hume had the greatest respect for the author of the Analogy, ranks him with Locke and Berkeley as an originator of the experimental method in moral science, and in his specially theological essays, such as that on Particular Providence and a Future State, has Butler's views specifically in mind. (See Butler.) The success of the Essays, though hardly great enough to satisfy his somewhat exorbitant cravings, was a great encouragement to him. He began to hope that his earlier work, if recast and lightened, might share the fortunes of its successor; and at intervals throughout the next four years he occupied himself in rewriting it in a more succinct form with all the literary grace at his command. Meantime he continued to look about for some post which might secure him the modest independence he desired. In 1744 we find him, in anticipation of a vacancy in the chair of moral philosophy at Edinburgh university, moving his friends to advance his cause with the electors; and though, as he tells us, " the accusation of heresy, deism, scepticism or theism, &c., &c., was started " against him, it had no effect, " being bore down by the contrary authority of all the good people in town." To his great mortification, however, he found out, as he thought, that Hutcheson and Leechman, with whom he had been on terms of friendly correspondence, were giving the weight of their opinion against his election. The after history of these negotiations is obscure. Failing in this attempt, he was induced to become tutor, or keeper, to the marquis of Annandale, a harmless literary lunatic. This position, financially advantageous, was absurdly false (see letters in Burton's Life, i. ch. v.), and when the matter ended Hume had to sue for arrears of salary.
In 1746 Hume accepted the office of secretary to General St Clair, and was a spectator of the ill-fated expedition to France in the autumn of that year. His admirable account of the transaction has been printed by Burton. After a brief sojourn at Ninewells, doubtless occupied in preparing for publication his Philosophical Essays (afterwards entitled An Inquiry concerning Human Understanding), Hume was again associated with General St Clair as secretary in the embassy to Vienna and Turin (1748). The notes of this journey are written in a light and amusing style, showing Hume's usual keenness of sight in some directions and his almost equal blindness in others.
During his absence from England, early in the year 1748, the Philosophical Essays were published; but the first reception of the work was little more favourable than that accorded to the Treatise. To the later editions of the work Hume prepared an " Advertisement " referring to the Treatise, and desiring that the Essays " may alone be regarded as containing his philosophical sentiments and principles." Some modern critics have accepted this disclaimer as of real value, but in fact it has no significance; and Hume himself in a striking letter to Gilbert Elliott indicated the true relation of the two works. " I believe the Philosophical Essays contain everything of consequence relating to the understanding which you would meet with in the Treatise, and I give you my advice against reading the latter. By shortening and simplifying the questions, I really render them much more complete. Addo dum rninuo. The philosophical principles are the same in both." The Essays are undoubtedly written with more maturity and skill than the Treatise; they contain in more detail application of the principles to concrete problems, such as miracles, providence, immortality; but the entire omission of the discussion forming part ii. of the first book of the Treatise, and the great compression of part iv., are real defects which must always render the Treatise the more important work.
In 1749 Hume returned to Ninewells, enriched with " near a thousand pounds." In 1751 he removed to Edinburgh, where for the most part he resided during the next twelve years of his life. These years are the richest so far as literary production is concerned. In 1751 he published his Political Discourses, which had a great and well-deserved success both in England and abroad. It was translated into French by Mauvillon (1753) and by the Abbe le Blanc (1754). In the same year appeared the recast of the third book of the Treatise, called Inquiry concerning the Principles of Morals, of which he says that " of all his writings, philosophical, literary or historical, it is incomparably the best." At this time also we hear of the Dialogues concerning Natural Religion, a work which Hume was prevailed on not to publish, but which he revised with great care, and evidently regarded with the greatest favour. The work itself, left by Hume with instructions that it should be published, did not appear till 1779.
In 1751 Hume was again unsuccessful in the attempt to gain a professor's chair. In the following year he received, in spite of the usual accusations of heresy, the librarianship of the Advocates' Library in Edinburgh, small in emoluments (40 a year) but rich in opportunity for literary work. In a playful letter to Dr Clephane, he describes his satisfaction at his appointment, and attributes it in some measure to the support of " the ladies." In 1753 Hume was fairly settled in Edinburgh, preparing for his History of England. He had decided to begin the History, not with Henry VII., as Adam Smith recommended, but with James I., considering that the political differences of his time took their origin from that period. On the whole his attitude in respect to disputed political principles seems not to have been at first consciously unfair. As for the qualities necessary to secure success as a writer on history, he felt that he possessed them in a high degree; and, though neither his ideal of an historian nor his equipment for the task of historical research would now appear adequate, in both he was much in advance of his time. " But," he writes in the well-known passage of his Life, " miserable was my disappointment. I was assailed by one cry of reproach, disapprobation, and even detestation;. .. what was still more mortifying, the book seemed to sink into oblivion. Mr Millar told me that in a twelvemonth he sold only forty-five copies of it." This account must be accepted with reservations. It expresses Hume's feelings rather than the real facts. In Edinburgh, as we learn from one of his letters, the book succeeded well, no fewer than 450 copies being disposed of in five weeks. Nor is there anything in Hume's correspondence to show that the failure of the book was so complete as he declared. Within a very few years the sale of the History was sufficient to gain for the author a larger revenue than had ever before been known in his country to flow from literature, and to place him in comparative affluence. He seems to have received 400 for the first edition of the first volume, £700 for the first edition of the second and 0840 for the copyright of the two together. At the same time the bitterness of Hume's feelings and their effect are of importance in his life. It is from the publication of the History that we date his virulent hatred of everything English, towards society in London, Whig principles, Whig ministers and the public generally (see Burton's Life, ii. 268, 4 1 7, 434). He was convinced that there was a conspiracy to suppress and destroy everything Scottish.' The remainder of the History became little better than a party pamphlet. The second volume, published in 1756, carrying on the narrative to the Revolution, was better received than the first; but Hume then resolved to work backwards, and to show from a survey of the Tudor period that his Tory notions were grounded upon the history of the constitution. In 1759 this portion of the work appeared, and in 1761 the work was completed by the history of the pre-Tudor periods. The numerous editions of the various portions - for, despite Hume's wrath and grumblings, the book was a great literary success - gave him an opportunity of careful revision, which he employed to remove from it all the ' villainous seditious Whig strokes," and " plaguy prejudices of Whiggism " that he could detect. In other words, he bent all his efforts toward making his History more of a party work than it had been, and in his effort he was entirely successful. The early portion of his History may be regarded as now of little or no value. The sources at Hume's command were few, and he did not use them all. None the less, the History has a distinct place in the literature of England. It was the first attempt at a comprehensive treatment of historic facts, the first to introduce the social and literary aspects of a nation's life as only second in importance to its political fortunes, and the first historical writing in an animated yet refined and polished style.2 While the History was in process of publication, Hume did not entirely neglect his other lines of activity. In 1757 appeared Four Dissertations: The Natural History of Religion, Of the Passions, Of Tragedy, Of the Standard of Taste. Of these the dissertation on the passions is a very subtle piece of psychology, containing the essence of the second book of the Treatise. It is remarkable that Hume does not appear to have been acquainted with Spinoza's analysis of the affections. The last two essays are contributions of no great importance to aesthetics, a department of philosophy in which Hume was not strong. The Natural History of Religion is a powerful contribution to the deistic controversy; but, as in the case of Hume's earlier work, its significance was at the time overlooked. It is an attempt to carry the war into a province hitherto allowed to remain at peace, the theory of the general development of religious ideas. Deists, though raising doubts regarding the historic narratives of the Christian faith, had never disputed the general fact that belief in one God was natural and primitive. Hume endeavours to show that polytheism was the earliest as well as the most natural form of religious belief, and that theism or deism is ' See Burton, ii. 265, 148 and 238. Perhaps our knowledge of Johnson's sentiments regarding the Scots in general, and of his expressions regarding Hume and Smith in particular, may lessen our surprise at this vehemence.
2 Macaulay describes Hume's characteristic fault as an historian: " Hume is an accomplished advocate. Without positively asserting much more than he can prove, he gives prominence to all the circumstances which support his case; he glides lightly over those which are unfavourable to it; his own witnesses are applauded and encouraged; the statements which seem to throw discredit on them are controverted; the contradictions into which they fall are explained away; a clear and connected abstract of their evidence is given. Everything that is offered on the other side is scrutinized with the utmost severity; every suspicious circumstance is a ground for argument and invective; what cannot be denied is extenuated, or passed by without notice; concessions even are sometimes made; but this insidious candour only increases the effect of the vast mass of sophistry." - Miscell. Writings, " History." With this may be compared the more favourable verdict by J. S. Brewer, in the preface to his edition of the Student's Hume. the product of reflection upon experience, thus reducing the valiuity of the historical argument to that of the theoretical proofs.
In 1763 he accompanied Lord Hertford to Paris, doing the duties of secretary to the embassy, with the prospect of the appointment to that post. He was everywhere received " with the most extraordinary honours." The society of Paris was peculiarly ready to receive a great philosopher and historian, especially if he were known to be an avowed antagonist of religion, and Hume made valuable friendships, especially with D'Alembert and Turgot, the latter of whom profited much by Hume's economical essays. In 1766 he left Paris and returned to Edinburgh. In 1767 he accepted the post of under-secretary to General Conway and spent two years in London.
He settled finally in Edinburgh in 1769, having now through his pension and otherwise an income of £1000 a year. The solitary incident of note in this period of his life is the ridiculous quarrel with Rousseau, which throws much light upon the character of the great sentimentalist. Hume certainly did his utmost to secure for Rousseau a comfortable retreat in England, but his usually sound judgment seems at first to have been quite at fault with regard to his protege. The quarrel which all the acquaintances of the two philosophers had predicted soon came, and no language had expressions strong enough for Rousseau's anger. Hume came well out of the business, and had the sagacity to conclude that his admired friend was little better than a madman. In one of his most charming letters he describes his life in Edinburgh. The new house to which he alludes was built under his own directions at the corner of what is now called St David Street after him; it became the centre of the most cultivated society of Edinburgh. Hume's cheerful temper, his equanimity, his kindness to literary aspirants and to those whose views differed from his own won him universal respect and affection. He welcomed the work of his friends (e.g. Robertson and Adam Smith), and warmly recognized the worth of his opponents (e.g. George Campbell and Reid). He assisted Blackwell and Smollett in their difficulties and became the acknowledged patriarch of literature.
In the spring of 1775 Hume was struck with a tedious and harassing though not painful illness. A visit to Bath seemed at first to have produced good effects, but on the return journey more alarming symptoms developed themselves, his strength rapidly sank, and, little more than a month later, he died in Edinburgh on the 25th of August 1776.
No notice of Hume would be complete without the sketch of his character drawn by his own hand: " 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 dispositions, of command of temper, of an open, social and cheerful humour, capable of attachment, but little susceptible of enmity, and of great moderation in all my passions. Even my love of literary fame, my ruling passion, never soured my temper, notwithstanding my frequent disappointments. My company 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 seem to be disarmed on my behalf of their wonted fury. My friends never had occasion to vindicate any one circumstance of my character and conduct; 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 probability. I cannot say there is no vanity in making this funeral oration of myself, but I hope it is not a misplaced one; and this is a matter of fact which is easily cleansed and ascertained." The more his life has become known, the more confidence we place in this admirable estimate.
The results of Hume's speculations may be discussed under two heads: - (1) philosophical, (2) economical.
1. The philosophical writings, which mark a distinct epoch in the development of modern thought, can here be considered in two Phlloa only of the many aspects in which they present themselves sophy. as of the highest interest to the historian of philosophy. In the Treatise of Human Nature, which is in every respect the most complete exposition of Hume's philosophical conception, we have the first thorough-going attempt to apply the fundamental principles of Locke's empirical psychology to the construction of a theory of knowledge, and, as a natural consequence, the first systematic criticism of the chief metaphysical notions from this point of view. Hume, in that work, holds the same relation to Locke and Berkeley as the late J. S. Mill held with his System of Logic to Hartley and James Mill. In certain of the later writings, pre-eminently in the Dialogues on Natural Religion, Hume brings the result of his speculative criticism to bear upon the problems of current theological discussion, and gives in their regard, as previously with respect to general philosophy, the final word of the empirical theory in its earlier form. The interesting parallel between Hume and J. S. Mill in this second feature will not be overlooked.
In the first instance, then, Hume's philosophical work is to be regarded as the attempt to supply for empiricism in psychology a consistent, that is, a logically developed theory of knowledge. In Locke, indeed, such theory is not wanting, but, of all the many inconsistencies in the Essay on the Human Understanding, none is more apparent or more significant than the complete want of harmony between the view of knowledge developed in the fourth book and the psychological principles laid down in the earlier part of the work. Though Locke, doubtless, drew no distinction between the problems of psychology and of theory of knowledge, yet the discussion of the various forms of cognition given in the fourth book of the Essay seems to be based on grounds quite distinct from and in many respects inconsistent with the fundamental psychological principle of his work. The perception of relations, which, according to him, is the essence of cognition, the demonstrative character which he thinks attaches to our inference of God's existence, the intuitive knowledge of self, are doctrines incapable of being brought into harmony with the view of mind and its development which is the keynote of his general theory. To some extent Berkeley removed this radical inconsistency, but in his philosophical work it may be said with safety there are two distinct aspects, and while it holds of Locke on the one hand, it stretches forward to Kantianism on the other. Nor in Berkeley are these divergent features ever united into one harmonious whole. It was left for Hume to approach the theory of knowledge with full consciousness from the psychological point of view, and to work out the final consequences of that view so far as cognition is concerned. The terms wh: ch he employs in describing the aim and scope of his work are not those which we should now employ, but the declaration, in the introduction to the Treatise, that the science of human nature must be treated according to the experimental method, is in fact equivalent to the statement of the principle implied in Locke's Essay, that the problems of psychology and of theory of knowledge are identical. This view is the characteristic of what we may call the English school of philosophy.
In order to make perfectly clear the full significance of the principle which Hume applied to the solution of the chief philosophical questions, it is necessary to render somewhat more precise and complete the statement of the psychological view Theory which lies at the foundation of the empirical theory, and to distinguish from it the problem of the theory of knowledge upon which it was brought to bear. Without entering into details, which it is the less necessary to do because the subject has been recently discussed with great fulness in works readily accessible, it may be said that for Locke as for Hume the problem of psychology was the exact description of the contents of the individual mind, and the determination of the conditions of the origin and development of conscious experience in the individual mind. And the answer to the problem which was furnished by Locke is in effect that with which Hume started. The conscious experience of the individual is the result of interaction between the individual mind and the universe of things. This solution presupposes a peculiar conception of the general relation between the mind and things which in itself requires justification, and which, so far at least as the empirical theory was developed by Locke and his successors, could not be obtained from psychological analysis. Either we have a right to the assumption contained in the conception of the individual mind as standing in relation to things, in which case the grounds of the assumption must be sought elsewhere than in the results of this reciprocal relation, or we have no right to the assumption, in which case reference to the reciprocal relation can hardly be accepted as yielding any solution of the psychological problem. But in any case, - and, as we shall see, Hume endeavours so to state his psychological premises as to conceal the assumption made openly by Locke, - it is apparent that this psychological solution does not contain the answer to the wider and radically distinct problem of the theory of knowledge. For here we have to consider how the individual intelligence comes to know any fact whatsoever, and what is meant by the cognition of a fact. With Locke, Hume professes to regard this problem as virtually covered or answered by the fundamental psychological theorem; but the superior clearness of his reply enables us to mark with perfect precision the nature of the difficulty inherent in the attempt to regard the two as identical. For purposes of psychological analysis the conscious experience of the individual mind is taken as given fact, to be known, i.e. observed, discriminated, classified and explained in the same way in which any one special portion of experience is treated. Now if this mode of treatment be accepted as the only possible method, and its results assumed to be conclusive as regards the problem of knowledge, the fundamental peculiarity of cognition is overlooked. In all cognition, strictly so-called, there is involved a certain synthesis or relation of parts of a characteristic nature, and if we attempt to discuss this synthesis as though it were in itself but one of the facts forming the matter of knowledge, we are driven to regard this relation as being of the quite external kind discovered by observation among matters of knowledge. The difficulty of reconciling the two views is that which gives rise to much of the obscurity in Locke's treatment of the theory of knowledge; in Hume the effort to identify them, and to explain the synthesis which is essential to cognition as merely the accidental result of external relations among the elements of conscious experience, appears with the utmost clearness, and gives the keynote of all his philosophical work. The final perplexity, concealed by various forms of expression, comes forward at the close of the Treatise as absolutely unsolved, and leads Hume, as will be pointed out, to a truly remarkable confession of the weakness of his own system.
While, then, the general idea of a theory of knowledge as based upon psychological analysis is the groundwork of the Treatise, it is a particular consequence of this idea that furnishes to Hume the characteristic criterion applied by him to all philosophical questions. If the relations involved in the fact of cognition are only those discoverable by observation of any particular portion of known experience, then such relations are quite external and contingent. The only necessary relation which can be discovered in a given fact of experience is that of non-contradiction (i.e. purely formal); the thing must be what it is, and cannot be conceived as having qualities contradictory of its nature. The universal test, therefore, of any supposed philosophical principle is the possibility or impossibility of imagining its contradictory. All our knowledge is but the sum of our conscious experience, and is consequently material for imagination. " Let us fix our attention out of ourselves as much as possible; let us chase our imagination to the heavens or to the utmost limits of the universe; we never really advance a step beyond ourselves, nor can conceive any kind of existence, but those perceptions which have appeared in that narrow compass. This is the universe of the imagination, nor have we any idea but what is there produced." (Works, ed. of 1854, i. 93, cf. i. 107.) The course of Hume's work follows immediately from his fundamental principle, and the several divisions of the treatise, so far as the theoretical portions are concerned, are but its logical consequences. The first part of the first book contains a brief statement of the contents of mind, a description of all that observation can discover in conscious experience. The second part deals with those judgments which rest upon the formal elements of experience, space and time. The third part discusses the principle of real connexion among the elements of experience, the relation of cause and effect. The fourth part is virtually a consideration of the ultimate significance of this conscious experience, of the place it is supposed to occupy in the universe of existence, in other words, of the relations between the conscious experience of an individual mind as disclosed to observation and the supposed realities of self and external things.
In the first part Hume gives his own statement of the psychological foundations of his theory. Viewing the contents of mind as matter of experience, he can discover among them only and im- one distinction, a distinction expressed by the terms. impressions and ideas. Ideas are secondary in nature, copies of data supplied we know not whence. All that appears in conscious experience as primary, as arising from some unknown cause, and therefore relatively as original, Hume designates by the term impression, and claims to imply by such term no theory whatsoever as to the origin of this portion of experience. There is simply the fact of conscious experience, ultimate and inexplicable. Moreover, if we remain faithful to the fundamental conception that the contents of the mind are merely matters of experience, it is evident in the first place that as impressions are strictly individual, ideas also must be strictly particular, and in the second place that the faculties of combining, discriminating, abstracting and judging, which Locke had admitted, are merely expressions for particular modes of having mental experience, i.e. are modifications of conceiving (cf. i. 128 n., 137, 192). By this theory, Hume is freed from all the problems of abstraction and judgment. A comparative judgment is simplified into an isolated perception of a peculiar form, and a series of similar facts are grouped under a single symbol, representing a particular perception, and only by the accident of custom treated as universal (see i. 37, 38, 100).
Such, in substance, is Hume's restatement of Locke's empirical view. Conscious experience consists of isolated states, each of which is to be regarded as a fact and is related to others in a quite external fashion. It remains to be seen how knowledge can be explained on such a basis; but, before proceeding to sketch Hume's answer to this question, it is necessary to draw attention, first, to the peculiar device invariably resorted to by him when any exception to his general principle that ideas are secondary copies of impressions presents itself, and, secondly, to the nature of the substitute offered by him for that perception of relations or synthesis which even in Locke's confused statements had appeared as the essence of cognition. Whenever Hume finds it impossible to recognize in an idea the mere copy of a particular impression, he introduces the phrase " manner of conceiving." Thus general or abstract ideas are merely copies of a particular impression conceived in a particular manner. The ideas. of space and time, as will presently be pointed out, are copies of impressions conceived in a particular manner. The idea of necessary connexion is merely the reproduction of an impression which the mind feels itself compelled to conceive in a particular manner. Such a fashion of disguising difficulties points, not only to an inconsistency in Hume's theory as stated by himself, but to the initial error upon which it proceeds; for these perplexities are but the consequences of the doctrine that cognition is to be explained on the basis of particular perceptions. These external relations are, in fact, what Hume describes as the natural bonds of connexion among ideas, and, regarded subjectively as principles of association among the facts of mental experience, they form the substitute he offers for the synthesis implied in knowledge. These principles of association determine the imagination to combine ideas in various modes, and by this mechanical combination Hume, for a time, endeavoured to explain what are otherwise called judgments of relation. It was impossible, however, for him to carry out this view consistently. The only combination which, even in appearance, could be explained satisfactorily by its means was the formation of a complex idea out of simpler parts, but the idea of a relation among facts is not accurately described as a complex idea; and, as such relations have na basis in impressions, Hume is finally driven to a confession of the absolute impossibility of explaining them. Such confession, however, is only reached after a vigorous effort had been made to render some account of knowledge by the experimental method.
The psychological conception, then, on the basis of which Hume proceeds to discuss the theory of knowledge, is that of conscious experience as containing merely the succession of isolated impressions and their fainter copies, ideas, and as bound on. together by merely natural or external links of connexion, the principles of association among ideas. The foundations of cognition must be discovered by observation or analysis of experience so conceived. Hume wavers somewhat in his division of the various kinds of cognition, laying stress now upon one now upon another of the points in which mainly they differ from one another. Nor is it of the first importance, save with the view of criticizing his own consistency, that we should adopt any of the divisions implied in his exposition. For practical purposes we may regard the most important discussions in the Treatise as falling under two heads. In the first place there are certain principles of cognition which appear to rest upon and to express relations of the universal elements in conscious experience, viz. space and time. The propositions of mathematics seem to be independent of this or that special fact of experience, and to remain unchanged even when the concrete matter of experience varies. They are formal. In the second place, cognition, in any real sense of that term, implies connexion for the individual mind between the present fact of experience and other facts, whether past or future. It appears to involve, therefore, some real relation among the portions of experience, on the basis of which relation judgments and inferences as to matters of fact can be shown to rest. The theoretical question is consequently that of the nature of the supposed relation, and of the certainty of judgments and inferences resting on it.
Hume's well-known distinction between relations of ideas and matters of fact corresponds fairly to this separation of the formal and real problems in the theory of cognition, although that distinction is in itself inadequate and not fully representative of Hume's own conclusions.
With regard, then, to the first problem, the formal element in knowledge, Hume has to consider several questions, distinct in nature and hardly discriminated by him with sufficient precision. For a complete treatment of this portion of the theory of knowledge, there require to be taken into consideration at least the following points: (a) the exact nature and significance of the space and time relations in our experience, (b) the mode in which the primary data, facts or principles, of mathematical cognition are obtained, (c) the nature, extent and certainty of such data, in themselves and with reference to the concrete material of experience, (d) the principle of inference from the data, however obtained. Not all of these points are discussed by Hume with the same fulness, and with regard to some of them it is difficult to state his conclusions. It will be of service, however, to attempt a summary of his treatment under these several heads, - the more so as almost all expositions of his philosophy are entirely defective in the account given of this essential portion. The brief statement in the Inquiry, § iv., is of no value, and indeed is almost unintelligible unless taken in reference to the full discussion contained in part ii. of the Treatise. (a) The nature of space and time as elements in conscious experience is considered by Hume in relation to a special problem, that of their supposed infinite divisibility. Evidently upon his and view of conscious experience, of the world of imagination, ti such infinite divisibility must be a fiction. The ultimate elements of experience must be real units, capable of being represented or imagined in isolation. Whence then do these units arise? or, if we put the problem as it was necessary Hume should put it to himself, in what orders or classes of impressions do we find the elements of space and time? Beyond all question Hume, in endeavouring to answer this problem, is brought face to face with one of the difficulties inherent in his conception of conscious experience.
For he has to give some explanation of the nature of space and time which shall identify these with impressions, and at the same time is compelled to recognize the fact that they are not identical with any single impression or set of impressions. Putting aside, then, the various obscurities of terminology, such as the distinction between the objects known, viz. " points " or several mental states, and the impressions themselves, which disguise the full significance of his conclusion, we find Hume reduced to the following as his theory of space and time. Certain impressions, the sensations of sight and touch, have in themselves the element of space, for these impressions (Hume skilfully transfers his statement to the points) have a certain order or mode of arrangement. This mode of arrangement or manner of disposition is common to coloured points and tangible points, and, considered separately, is the impression from which our idea of space is taken. All impressions and all ideas are received, or form parts of a mental experience only when received, in a certain order, the order of succession. This manner of presenting themselves is the impression from which the idea of time takes its rise.
It is almost superfluous to remark, first, that Hume here deliberately gives up his fundamental principle that ideas are but the fainter copies of impressions, for it can never be maintained that order of disposition is an impression, and, secondly, that he fails to offer any explanation of the mode in which coexistence and succession are possible elements, of cognition in a conscious experience made up of isolated presentations and representations. For the consistency of his theory, however, it was indispensable that he should insist upon the real, i.e. presentative character of the ultimate units of space and time.
(b) How then are the primary data of mathematical cognition to be derived from an experience containing space and time relations in Hume, in regard to this problem, distinctly separates geometry from algebra and arithmetic, i.e. he views extensive quantity as being cognized differently from number. With regard to geometry, he holds emphatically that it is an empirical doctrine, a science founded on observation of concrete facts. The rough appearances of physical facts, their outlines, surfaces and so on, are the data of observation, and only by a method of approximation do we gradually come near to such propositions as are laid down in pure geometry. He definitely repudiates a view often ascribed to him, and certainly advanced by many later empiricists, that the data of geometry are hypothetical. The ideas of perfect lines, figures and surfaces have not, according to him, any existence. (See Works, i. 66, 69, 73, 97 and iv. 180.) It is impossible to give any consistent account of his doctrine regarding number. He holds, apparently, that the foundation of all the science of number is the fact that each element of conscious experience is presented as a unit, and adds that we are capable of considering any fact or collection of facts as a unit. This manner of conceiving is absolutely general and distinct, and accordingly affords the possibility of an all-comprehensive and perfect science, the science of discrete quantity. (See Works, i. 97.) (c) In respect to the third point, the nature, extent and certainty of the elementary propositions of mathematical science, Hume's utterances are far from clear. The principle with which he starts and from which follows his well-known distinction between relations of ideas and matters of fact, a distinction which Kant appears to have thought identical with his distinction between analytical and synthetical judgments, is comparatively simple. The ideas of the quantitative aspects of phenomena are exact representations of these aspects or quantitative impressions; consequently, whatever is found true by consideration of the ideas may be asserted regarding the real impressions. No question arises regarding the existence of the fact represented by the idea, and in so far, at least, mathematical judgments may be described as hypothetical. For they simply assert what will be found true in any conscious experience containing coexisting impressions of sense (specifically, of sight and touch), and in its nature successive. That the propositions are hypothetical in this fashion does not imply any distinction between the abstract truth of the ideal judgments and the im p erfect correspondence of concrete material with these abstract relations. Such distinction is quite foreign to Hume, and can only be ascribed to him from an entire misconception of his view regarding the ideas of space and time. (For an example of such misconception, which is almost universal, see Riehl, Der philosophische Kriticismus, i. 96, 97.) (d) From this point onwards Hume's treatment becomes exceedingly confused. The identical relation between the ideas of space and time and the impressions corresponding to them apparently leads him to regard judgments of continuous and discrete quantity as standing on the same footing, while the ideal character of the data gives a certain colour to his inexact statements regarding the extent and truth of the judgments founded on them. The emphatic utterances in the Inquiry (iv. 30, 186), and even at the beginning of the relative section in the Treatise (i. 95) may be cited in illustration. But in both works these utterances are qualified in such a manner as to enable us to perceive the real bearings of his doctrine, and to pronounce at once that it differs widely from that commonly ascribed to him. " It is 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, so long as our idea remains the same " (i. 95). If taken in isolation this passage might appear sufficient justification for Kant's view that, according to Hume, geometrical judgments are analytical and therefore perfect. But it is to be recollected that, according to Hume, an idea is actually a representation or individual picture, not a notion or even a schema, and that he never claims to be able to extract the predicate of a geometrical judgment by analysis of the subject. The properties of this individual subject, the idea of the triangle, are, according to him, discovered by observation, and as observation, whether actual or ideal, never presents us with more than the rough or general appearances of geometrical quantities, the relations so discovered have only approximate exactness. " Ask a mathematician what he means when he pronounces two quantities to be equal, and he must say that the idea of equality is one of those which cannot be defined, and that it is sufficient to place two equal quantities before any one in order to suggest it. Now this is an appeal to the general appearances of objects to the imagination or senses " (iv. 180). " Though it (i.e. geometry) much excels, both in universality and exactness, the loose judgments of the senses and imagination, yet [it] never attains a perfect precision and exactness " (i. 97). Any exactitude attaching to the conclusions of geometrical reasoning arises from the comparative simplicity of the data for the primary judgments.
So far, then, as geometry is concerned, Hume's opinion is perfectly definite. It is an experimental or observational science, founded on primary or immediate judgments (in his phraseology, perceptions), of relation between facts of intuition; its conclusions are hypothetical only in so far as they do not imply the existence at the moment of corresponding real experience; and its propositions have no exact truth. With respect to arithmetic and algebra, the science of numbers, he expresses an equally definite opinion, but unfortunately it is quite impossible to state in any satisfactory fashion the grounds for it or even its full bearing. He nowhere explains the origin of the notions of unity and number, but merely asserts that through their means we can have absolutely exact arithmetical propositions (Works, i. 97, 98). Upon the nature of the reasoning by which in mathematical science we pass from data to conclusions, Hume gives no explicit statement. If we were to say that on his view the essential step must be the establishment of identities or equivalences, we should probably be doing justice to his doctrine of numerical reasoning, but should have some difficulty in showing the application of the method to geometrical reasoning. For in the latter case we possess, according to Hume, no standard of equivalence other than that supplied by immediate observation, and consequently transition from one premise to another by way of reasoning must be, in geometrical matters, a purely verbal process.
Hume's theory of mathematics - the only one, perhaps, which is compatible with his fundamental principle of psychology - is a practical condemnation of his empirical theory of perception. He has not offered even a plausible explanation of the mode by which a consciousness made up of isolated momentary impressions and ideas can be aware of coexistence and number, or succession. The relations. of ideas are accepted as facts of immediate observation, as being themselves perceptions or individual elements of conscious experience, and to all appearance they are regarded by Hume as being in a sense analytical, because the formal criterion of identity is applicable to them. It is applicable, however, not because the predicate is contained in the subject, but on the principle of contradiction. If these judgments are admitted to be facts of immediate perception, the supposition of their non-existence is impossible. The ambiguity in his criterion, however, seems entirely to have escaped Hume's attention.
A somewhat detailed consideration of Hume's doctrine with regard to mathematical science has been given for the reason that this portion of his theory has been very generally overlooked or misinterpreted. It does not seem necessary to endeavour to follow his minute examination of the principle of real cognition with the same fulness. It will probably be sufficient to indicate the problem as conceived by Hume, and the relation of the method he adopts for solving it to the fundamental doctrine of his theory of knowledge.
Real cognition, as Hume points out, implies transition from the present impression or feeling to something connected with it. As this thing can only be an impression or perception, and is not itself present, it is represented by its copy or idea. Now the supreme, all-comprehensive link of connexion between present feeling or impression and either past or future experience is that of causation. The idea in question is, therefore, the idea of something connected with the present impression as its cause or effect. But this is explicitly the idea of the said thing as having had or as about to have existence, - in other words, belief in the existence of some matter of fact. What, for a conscious experience so constituted as Hume will admit, is the precise significance of such belief in real existence ?
Clearly the real existence of a fact is not demonstrable. For whatever is may be conceived not to be. " No negation of a fact can involve a contradiction." Existence of any fact, not present as a perception, can only be proved by arguments from cause or effect. But as each perception is in consciousness only as a contingent fact, which might not be or might be other than it is, we must admit that the mind can conceive no necessary relations or connexions among the several portions of its experience.
If, therefore, a present perception leads us to assert the existence of some other, this can only be interpreted as meaning that in some natural, i.e. psychological, manner the idea of this other perception is excited, and that the idea is viewed by the mind in some peculiar fashion. The natural link of connexion Hume finds in the similarities presented by experience. One fact or perception is discovered by experience to be uniformly or generally accompanied by another, and its occurrence therefore naturally excites the idea of that other. But when an idea is so roused up by a present impression, and when this idea, being a consequence of memory, has in itself a certain vivacity or liveliness, we regard it with a peculiar indefinable feeling, and in this feeling consists the immense difference between mere imagination and belief. The mind is led easily and rapidly from the present impression to the ideas of impressions found by experience to be the usual accompaniments of the present fact. The ease and rapidity of the mental transition is the sole ground for the supposed necessity of the causal connexion between portions of experience. The idea of necessity is not intuitively obvious; the ideas of cause and effect are correlative in our minds, but only as a result of experience. Hobbes and Locke were wrong in saying that the mind must find in the relation the idea of Power. We mistake the sub j ective transition resting upon custom or past experience for an objective connexion independent of special feelings. All reasoning about matters of fact is therefore a species of feeling, and belongs to the sensitive rather than to the cogitative side of our nature. It should be noted that this theory of Causation entirely denies the doctrine of Uniformity in Nature, so far as the human mind is concerned. All alleged uniformity is reduced to observed similarity of process. The idea is a mere convention, product of inaccurate thinking and custom.
While it is evident that some such conclusion must follow from the attempt to regard the cognitive consciousness as made up of disconnected feelings, it is equally clear, not only that the result is selfcontradictory, but that it involves certain assumptions not in any way deducible from the fundamental view with which Hume starts. For in the problem of real cognition he is brought face to face with the characteristic feature of knowledge, distinction of self from matters known, and reference of transitory states to permanent objects or relations. Deferring his criticism of the significance of self and object, Hume yet makes use of both to aid his explanation of the belief attaching to reality. The reference of an idea to past experience has no meaning, unless we assume an identity in the object referred to. For a past impression is purely transitory, and, as Hume occasionally points out, can have no connexion of fact with the present consciousness. His exposition has thus a certain plausibility, which would not belong to it had the final view of the permanent object been already given.
The final problem of Hume's theory of knowledge, the discussion of the real significance of the two factors of cognition, self and external things, is handled in the Treatise with great fulness and dialectical subtlety.
As in the case of the previous problem, it is unnecessary to follow the steps of his analysis, which are, for the most part, attempts to self substitute qualities of feeling for the relations of thought The . which appear to be involved. The results follow with the cognition utmost ease from his original postulate. If there is nothing in conscious experience save what observation can disclose, while each act of observation is itself an isolated feeling (an impression or idea), it is manifest that a permanent identical thing can never be an object of experience. Whatever permanence or identity is ascribed to an impression or idea is the result of association, is one of those " propensities to feign " which are due to natural connexions among ideas. We regard as successive presentations of one thing the resembling feelings which are experienced in succession. Identity, then, whether of self or object, there is none, and the supposition of objects, distinct from impressions, is but a further consequence of our " propensity to feign." Hume's explanation of the belief in external things by reference to association is well deserving of careful study and of comparison with the more recent analysis of the same problem by J. S. Mill.
The weak points in Hume's empiricism are so admirably realized Negative by the author himself that it is only fair to quote his own Negativ of summary in the Appendix to the Treatise. He confesses result that, in confining all cognition to single perceptions and. supplying no purely intellectual faculty for modifying, treatise recording and classifying their results, he has destroyed real knowledge altogether: " 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 feels personal identity, when, reflecting on the train of past perceptions that compose a mind, the ideas of them are felt to be connected together and naturally introduce each other.
" However extraordinary this conclusion may seem, it need not surprise us. Modern philosophers seem inclined to think that personal identity arises from consciousness, and consciousness is nothing but a reflected thought or perception. The present philosophy, therefore, has a promising aspect. But all my hopes vanish when I come to explain the principles that unite our successive perceptions in our thought or consciousness. I cannot discover any theory which gives me satisfaction on this head... .
" In short, there are two principles which I cannot render consistent, nor is it in my power to renounce either of them; viz. that all our distinct perceptions are distinct existences, and that the mind never perceives any real connexion among distinct existences. Did our perceptions either inhere in something simple or individual, or did the mind perceive some real connexion among them, there would be no difficulty in the case " (ii. 551).
The closing sentences of this passage may be regarded as pointing to the very essence of the Kantian attempt at solution of the problem of knowledge. Hume sees distinctly that if conscious experience be taken as containing only isolated states, no progress in explanation of cognition is possible, and that the only hope of further development is to be looked for in a radical change in our mode of conceiving experience. The work of the critical philosophy is the introduction of this new mode of regarding experience, a mode which, in the technical language of philosophers, has received the title of transcendental as opposed to the psychological method followed by Locke and Hume. It is because Kant alone perceived the full significance of the change required in order to meet the difficulties of the empirical theory that we regard his system as the only sequel to that of Hume. The writers of the Scottish school, Reid in particular, did undoubtedly indicate some of the weaknesses in Hume's fundamental conception, and their attempts to show that the isolated feeling cannot be taken as the ultimate and primary unit of cognitive experience are efforts in the right direction. But the question of knowledge was never generalized by them, and their reply to Hume, therefore, remains partial and inadequate, while its effect is weakened by the uncritical assumption of principles which is a characteristic feature of their writings.
The results of Hume's theoretical analysis are applied by him to the problems of practical philosophy and religion. For the first of these the reader is referred to the article Ethics, where Theology Hume's views are placed in relation to those of his pre- and ethics. decessors in the same field of inquiry. His position, as regards the second, is very noteworthy. As before said, his metaphysic contains in abstracto the principles which were at that time being employed, uncritically, alike by the deists and by their antagonists. There can be no doubt that Hume has continually in mind the theological questions then current, and that he was fully aware of the mode in which his analysis of knowledge might be applied to them. A few of the less important of his criticisms, such as the argument on miracles, became then and have since remained public property and matter of general discussion. But the full significance of his work on the theological side was not at the time perceived, and justice has barely been done to the admirable manner in which he reduced the theological disputes of the century to their ultimate elements. The importance of the Dialogues on Natural Religion, as a contribution to the criticism of theological ideas and methods, can hardly be over-estimated. A brief survey of its contents will be sufficient to show its general nature and its relations to such works as Clarke's Demonstration and Butler's Analogy. The Dialogues introduce three interlocutors, Demea, Cleanthes and Philo, who represent three distinct orders of theological opinion. The first is the type of a certain a priori view, then regarded as the safest bulwark against infidelity, of which the main tenets were that the being of God was capable of a priori proof, and that, owing to the finitude of our faculties, the attributes and modes of operation of deity were absolutely incomprehensible. The second is the typical deist of Locke's school, improved as regards his philosophy, and holding that the only possible proof of God's existence was a posteriori, from design, and that such proof was, on the whole, sufficient. The third is the type of completed empiricism or scepticism, holding that no argument, either from reason or experience, can transcend experience, and consequently that no proof of God's existence is at all possible. The views of the first and second are played off against one another, and criticized by the third with great literary skill and effect. Cleanthes, who maintains that the doctrine of the incomprehensibility of God is hardly distinguishable from atheism, is compelled by the arguments of Philo to reduce to a minimum the conclusion capable of being inferred from experience as regards the existence of God. For Philo lays stress upon the weakness of the analogical argument, points out that the demand for an ultimate cause is no more satisfied by thought than by nature itself, shows that the argument from design cannot warrant the inference of a perfect or infinite or even of a single deity, and finally, carrying out his principles to the full extent, maintains that, as we have no experience of the origin of the world, no argument from experience can carry us to its origin, and that the apparent marks of design in the structure of animals are only results from the conditions of their actual existence. So far as argument from nature is concerned, a total suspension of judgment is our only reasonable resource. Nor does the a priori argument in any of its forms fare better, for reason can never demonstrate a matter of fact, and, unless we know that the world had a beginning in time, we cannot insist that it must have had a cause. Demea, who is willing to give up his abstract proof, brings forward the ordinary theological topic, man's consciousness of his own imperfection, misery and dependent condition. Nature is throughout corrupt and polluted, but " the present evil phenomena are rectified in other regions and in some future period of existence." Such a view satisfies neither of his interlocutors. Cleanthes, pointing out that from a nature thoroughly evil we can never prove the existence of an infinitely powerful and benevolent Creator, hazards the conjecture that the deity, though all-benevolent, is not all-powerful. Philo, however, pushing his principles to their full consequences, shows that unless we assumed (or knew) beforehand that the system of nature was the work of a benevolent but limited deity, we certainly could not, from the facts of nature, infer the benevolence of its creator. Cleanthes's view is, therefore, an hypothesis, and in no sense an inference.
The Dialogues ought here to conclude. There is, however, appended one of those perplexing statements of personal opinion (for Hume declares Cleanthes to be his mouthpiece) not uncommon among writers of this period. Cleanthes and Philo come to an agreement, in admitting a certain illogical force in the a posteriori argument, or, at least, in expressing a conviction as to God's existence, which may not perhaps be altogether devoid of foundation. The precise value of such a declaration must be matter of conjecture. Probably the true statement of Hume's attitude regarding the problem is the somewhat melancholy utterance with which the Dialogues close.
It is apparent, even from the brief summary just given, that the importance of Hume in the history of philosophy consists in the vigour and logical exactness with which he develops a particular metaphysical view. Inconsistencies, no doubt, are to be detected in his system, but they arise from the limitations of the view itself, and not, as in the case of Locke and Berkeley, from imperfect grasp of the principle, and endeavour to unite with it others radically incompatible. In Hume's theory of knowledge we have the final expression of what may be called psychological individualism or atomism, while his ethics and doctrine of religion are but the logical consequences of this theory. So far as metaphysic is concerned, Hume has given the final word of the empirical school, and all additions, whether from the specifically psychological side or from the general history of human culture, are subordinate in character, and affect in no way the nature of his results. It is no exaggeration to say that the later English school of philosophy represented by J. S. Mill made in theory no advance beyond Hume. In the logic of Mill, e.g., we find much of a special character that has no counterpart in Hume, much that is introduced ab extra, from general considerations of scientific procedure, but, so far as the groundwork is concerned, the System of Logic is a mere reproduction of Hume's doctrine of knowledge. It is impossible for any reader of Mill's remarkable posthumous essay on theism to avoid the reflection that in substance the treatment is identical with that of the Dialogues on Natural Religion, while on the whole the superiority in critical force must be assigned to the earlier work.
2. Hume's eminence in the fields of philosophy and history must not be allowed to obscure his importance as a political economist. Econom i cs. Berkeley had already, in the Querist, attacked the mercan t i le theory of the nature of national wealth and the functions of money, and Locke had, in a partial manner, shown that political economy could with advantage be viewed in relation to the modern system of critical philosophy. But Hume was the first to apply to economics the scientific methods of his philosophy. His services to economics may be summed up in two heads: (I) he established the relation between economic facts and the fundamental phenomena of social life, and (2) he introduced into the study of these facts the new historical method. Thus, though he gave no special name to it, he yet describes the subject-matter, and indicates the true method, of economic science. His economic essays were published in the volumes entitled Political Discourses (1752) and Essays and Treatises on Several Subjects (1753); the most important are those on Commerce, on Money, on Interest and on the Balance of Trade, but, notwithstanding the disconnected form of the essays in general, the other less important essays combine to make a complete economic system. We have said that Berkeley and Locke had already begun the general work for which Hume is most important; in details also Hume had been anticipated to some extent. Nicholas Barbon and Sir Dudley North had already attacked the mercantile theory as to the precious metals and the balance of trade; Joseph Massie and Barbon had anticipated his theory of interest. Yet when we compare Hume with Adam Smith, the advance which Hume had made on his predecessors in lucidity of exposition and subtlety of intellect becomes clear, and modern criticism is agreed that the main errors of Adam Smith are to be found in those deductions which deviate from the results of the Political Discourses. A very few examples must suffice to illustrate his services to economics.
In dealing with money, he refutes the Mercantile School, which had tended to confound it with wealth. " Money," said Hume, " is none of the wheels of trade; it is the oil which renders the motion of the wheels more smooth and easy." " Money and commodities are the real strength of any community." From the internal, as distinct from the international, aspect, the absolute quantity of money, supposed as of fixed amount, in a country, is of no consequence, while a quantity larger than is required for the interchange of commodities is injurious, as tending to raise prices and to drive foreigners from the home markets. It is only during the period of acquisition of money, and before the rise in prices, that the accumulation of precious metals is advantageous. This principle is perhaps Hume's most important economic discovery (cf. F. A. Walker's Money in its Relations to Trade and Industry, London, 1880, p. 84 sqq.). He goes on to show that the variations of prices are due solely to money and commodities in circulation. Further, it is a misconception to regard as injurious the passage of money into foreign countries. " A government," he says, " has great reason to preserve with care its people and its manufactures; its money it may safely trust to the course of human affairs without fear or jealousy." Dealing with the phenomena of interest, he exposes the old fallacy that the rate depends upon the amount of money in a country; low interest does not follow on abundance of money. The reduction in the rate of interest must, in general, result from " the increase of industry and frugality, of arts and commerce." In connexion with this he emphasizes a too generally neglected factor in economic phenomena, " the constant and insatiable desire of the mind for exercise and employment." " Interest," he says in general, " is the barometer of the state, and its lowness an almost infallible sign of prosperity," arising, as it does, from increased trade, frugality in the merchant class, and the consequent rise of new lenders: low interest and low profits mutually forward each other. In the matter of free trade and protection he compromises. He says on Free the one hand, " not only as a man, but as a British subject I pray for the flourishing commerce of Germany, Spain, Italy and even France itself," and condemns " the numerous bars, obstructions and imposts which all nations of Europe, and none more than England, have put upon trade." On the other hand, he approves of a protective tax on German linen in favour of home manufactures, and of a tax on brandy as encouraging the sale of rum and so supporting our southern colonies. Indeed it has been fairly observed that Hume retains an attitude of refined mercantilism. With regard to taxation he takes very definite views. The best taxes, he says, are those levied on consumption, especially on Taxation luxuries, for these are least heavily felt. He denies that all taxes fall finally on the land. Superior frugality and industry on the part of the artisan will enable him to pay taxes without mechanically raising the price of labour.
Here, as in other points, he differs entirely from the physiocrats, and his criticism of contemporary French views are, as a whole, in accordance with received modern opinion. For the modern expedient of raising money for national emergencies by way of loan he has a profound distrust. He was convinced that what is bad for the individual credit must be bad for the state also. A national debt, he maintains, enriches the capital at the expense of the provinces; further, it creates a leisured class of stockholders, and possesses all the disadvantages of paper credit. " Either the nation must destroy public credit, or public credit will destroy the nation." To sum up, it may be said that Hume enunciated the principle that " everything in the world is purchased by labour, and our passions are the only causes of labour "; and further, that, in analysing the complex phenomena of commerce, he is superior sometimes to Adam Smith in that he never forgets that the ultimate causes of economic change are the " customs and manners " of the people, and that the solution of problems is to be sought in the elementary factors of industry.
Bibliography.—1. Life.—J. H. Burton's Life and Correspondence of David Hume (2 vols., 1846); Dr G. Birkbeck Hill, Letters of Hume to William Strahan; C. J. W. Francke, David Hume (Haarlem, 1907).
2. Works.—Until 1874 the standard edition was that of 1826 (reprinted 1854), in 4 vols. The best modern edition is that in 4 vols. by T. H. Green and T. H. Grose (containing a valuable introduction and excellent bibliographical matter); the Enquiry and the Treatise (1894 and 1896, Oxford), edited by L. A. Selby-Bigge.
3. Philosophic (the more important only can be quoted).- Huxley's Hume (a popular reproduction of Hume's views in " English Men of Letters " series); Sir L. Stephen's English Thought in the XVIIIth Century (1876, especially ch. vi.); J. Orr, David Hume and his Influence on Philosophy and Theology (1903, especially ch. ix. on " Moral Theory of Hume "); H. Calderwood, David Hume (1898, especially ch. vii. on Hume's attitude to religion); A. Seth, Scottish and German Answers to Hume; F. Jodl, Leben and Philosophie D. Humes (1872); E. Pfleiderer, Empirismus and Skepsis in D. Humes Philosophie (1874); G. Spicker, Kant, Hume and Berkeley (1875); G. Compayre, La Philosophie de D. Hume (1873); A. Meinong, Hume-Studien (1877, especially Hume's nominalism); G. von Gizycki (a thorough exposition of Hume's utilitarianism), Die Ethik D. Humes (1878); G. Lechartier, D. Hume, moraliste et sociologue (1900); M. Klemme, Die volkswirtschaftlichen Anchauungen D. Humes (1900); E. Marcus, Kants Revolutionsprinzip. Eine exakte Losung des Kant-Hume'schen Erkenntnisproblems (1902); C. Hedvall, Humes Erkenntnistheorie (1906); R. Honigswald, Uber die Lehre Humes von der Realiteit der Aussendinge (1904); O. Quast, Der Begrif%des Belief bei David Hume (1903). Hume's relation to the society of his time is described in the Rev. H. G. Graham's Social Life in Scotland and Scottish Men of Letters; " Jupiter " in Carlyle's Autobiography. J. MacCosh published a short pamphlet (1884) containing interesting but perhaps not conclusive arguments on the Agnosticism of Hume and Huxley. 4. Economic. - J. Bonar, Philosophy and Political Economy (London, 1893), chapter on Hume; notes to W. G. F. Roscher's Principles of Political Economy (J. Lalor's trans. of 13th ed.,New York, 1878); F. A. Walker's Money (New York, 1877) gives an account of Hume's views on interest and money; H. H. Gibbs (Lord Aldenham), Colloquy on the Currency; for Hume's relation to Adam Smith, John Rae's Life of Adam Smith (London, 1895). See also M. Teisseire, Les Essais economiques de David Hume (1902; a critical study); A. Schatz, L'Ouvre economique de David Hume (1902). (R. Ad.; J. M. M.)