David Hume, (born May 7 [April 26, Old Style], 1711, Edinburgh, Scotland—died August 25, 1776, Edinburgh), Scottish philosopher, historian, economist, and essayist known especially for his philosophical empiricism and skepticism.

Hume conceived of philosophy as the inductive, experimental science of human nature. Taking the scientific method of the English physicist Sir Isaac Newton as his model and building on the epistemology of the English philosopher John Locke, Hume tried to describe how the mind works in acquiring what is called knowledge. He concluded that no theory of reality is possible; there can be no knowledge of anything beyond experience. Despite the enduring impact of his theory of knowledge, Hume seems to have considered himself chiefly as a moralist.

Early life and works

Hume was the younger son of Joseph Hume, the modestly circumstanced laird, or lord, of Ninewells, a small estate adjoining the village of Chirnside, about nine miles distant from Berwick-upon-Tweed on the Scottish side of the border. David’s mother, Catherine, a daughter of Sir David Falconer, president of the Scottish court of session, was in Edinburgh when he was born. In his third year his father died. He entered Edinburgh University when he was about 12 years old and left it at 14 or 15, as was then usual. Pressed a little later to study law (in the family tradition on both sides), he found it distasteful and instead read voraciously in the wider sphere of letters. Because of the intensity and excitement of his intellectual discovery, he had a nervous breakdown in 1729, from which it took him a few years to recover.

In 1734, after trying his hand in a merchant’s office in Bristol, he came to the turning point of his life and retired to France for three years. Most of this time he spent at La Flèche on the Loire, in the old Anjou, studying and writing A Treatise of Human Nature. The Treatise was Hume’s attempt to formulate a full-fledged philosophical system. It is divided into three books: Book I, “Of the Understanding,” discusses, in order, the origin of ideas; the ideas of space and time; knowledge and probability, including the nature of causality; and the skeptical implications of those theories. Book II, “Of the Passions,” describes an elaborate psychological machinery to explain the affective, or emotional, order in humans and assigns a subordinate role to reason in this mechanism. Book III, on morals, characterizes moral goodness in terms of “feelings” of approval or disapproval that people have when they consider human behaviour in the light of agreeable or disagreeable consequences, either to themselves or to others.

Although the Treatise is Hume’s most thorough exposition of his thought, at the end of his life he vehemently repudiated it as juvenile, avowing that only his later writings presented his considered views. The Treatise is not well constructed, in parts oversubtle, confusing because of ambiguity in important terms (especially “reason”), and marred by willful extravagance of statement and rather theatrical personal avowals. For those reasons his mature condemnation of it was perhaps not entirely misplaced. Book I, nevertheless, has been more read among academic philosophers than any other of his writings.

Returning to England in 1737, he set about publishing the Treatise. Books I and II were published in two volumes in 1739; Book III appeared the following year. The poor reception of this, his first and very ambitious work, depressed him; he later said, in his Autobiography, that “it fell dead-born from the press, without reaching such distinction, as even to excite a murmur among the zealots.” But his next venture, Essays, Moral and Political (1741–42), won some success. Perhaps encouraged by this, he became a candidate for the chair of moral philosophy at Edinburgh in 1744. Objectors alleged heresy and even atheism, pointing to the Treatise as evidence (Hume’s Autobiography notwithstanding, the work had not gone unnoticed). Unsuccessful, Hume left the city, where he had been living since 1740, and began a period of wandering: a sorry year near St. Albans as tutor to the mad marquess of Annandale (1745–46); a few months as secretary to Gen. James St. Clair (a member of a prominent Scottish family), with whom he saw military action during an abortive expedition to Brittany (1746); a little tarrying in London and at Ninewells; and then some further months with General St. Clair on an embassy to the courts of Vienna and Turin (1748–49).

Mature Works

During his years of wandering Hume was earning the money that he needed to gain leisure for his studies. Some fruits of those studies had already appeared before the end of his travels, viz., a further Three Essays, Moral and Political (1748) and Philosophical Essays Concerning Human Understanding (1748). The latter is a rewriting of Book I of the Treatise (with the addition of his essay “On Miracles,” which became notorious for its denial that a miracle can be proved by any amount or kind of evidence); it is better known as An Enquiry Concerning Human Understanding, the title Hume gave to it in a revision of 1758. The Enquiry Concerning the Principles of Morals (1751) was a rewriting of Book III of the Treatise. It was in those later works that Hume expressed his mature thought.

An Enquiry Concerning Human Understanding is an attempt to define the principles of human knowledge. It poses in logical form significant questions about the nature of reasoning in regard to matters of fact and experience, and it answers them by recourse to the principle of association. The basis of Hume’s exposition is a twofold classification of objects of awareness. In the first place, all such objects are either “impressions,” data of sensation or of internal consciousness, or “ideas,” derived from such data by compounding, transposing, augmenting, or diminishing. That is to say, the mind does not create any ideas but derives them from impressions. From this Hume develops a theory of linguistic meaning. A word that does not stand directly for an impression has meaning only if it brings before the mind an object that can be gathered from an impression by one of the mental processes just mentioned. In the second place, there are two approaches to construing meaning: an analytical one, which concentrates on the “relations of ideas,” and an empirical one, which focuses on “matters of fact.” Ideas can be held before the mind simply as meanings, and their logical relations to one another can then be detected by rational inspection. The idea of a plane triangle, for example, entails the equality of its internal angles to two right angles, and the idea of motion entails the ideas of space and time, irrespective of whether there really are such things as triangles and motion. Only on that level of mere meanings, Hume asserts, is there room for demonstrative knowledge. Matters of fact, on the other hand, come before the mind merely as they are, revealing no logical relations; their properties and connections must be accepted as they are given. That primroses are yellow, that lead is heavy, and that fire burns things are facts, each shut up in itself, logically barren. Each, so far as reason is concerned, could be different: the contradictory of every matter of fact is conceivable. Therefore, there can be no logically demonstrative science of fact.

From this basis Hume develops his doctrine about causality. The idea of causality is alleged to assert a “necessary connexion” among matters of fact. From what impression, then, is it derived? Hume states that no causal relation among the data of the senses can be observed, for, when people regard any events as causally connected, all that they do and can observe is that they frequently and uniformly go together. In this sort of togetherness it is a fact that the impression or idea of the one event brings with it the idea of the other. A habitual association is set up in the mind; and, as in other forms of habit, so in this one, the working of the association is felt as compulsion. This feeling, Hume concludes, is the only discoverable impressional source of the idea of causality.

Belief

Hume then considers the process of causal inference, and in so doing he introduces the concept of belief. When people see a glass fall, they not only think of its breaking but expect and believe that it will break. Or, starting from an effect, when they see the ground to be generally wet, they not only think of rain but believe that there has been rain. Thus belief is a significant component in the process of causal inference. Hume then proceeds to investigate the nature of belief, claiming that he was the first to do so. He uses the term, however, in the narrow sense of belief regarding matters of fact. He defines belief as a sort of liveliness or vividness that accompanies the perception of an idea. A belief, in other words, is a vivid or lively idea. This vividness is originally possessed by some of the objects of awareness—by impressions and by the simple memory-images of them. By association it comes to belong to certain ideas as well. In the process of causal inference, then, an observer passes from an impression to an idea regularly associated with it. In the process the aspect of liveliness proper to the impression infects the idea, Hume asserts. And it is this aspect of liveliness that Hume defines as the essence of belief.

Hume does not claim to prove that events themselves are not causally related or that they will not be related in the future in the same ways as they were in the past. Indeed, he firmly believes the contrary and insists that everybody else does as well. Belief in causality and in the resemblance of the future to the past are natural beliefs, inextinguishable propensities of human nature (madness apart), and even necessary for human survival. Rather, what Hume claims to prove is that such natural beliefs are not obtained from, and cannot be demonstrated by, either empirical observation or reason, whether intuitive or inferential. Although reflection shows that there is no evidence for them, it also shows that humans are bound to have them and that it is sensible and sane to do so. This is Hume’s skepticism: it is an affirmation of that tension, a denial not of belief but of certainty.

Morals and historical writing

The Enquiry Concerning the Principles of Morals is a refinement of Hume’s thinking on morality, in which he views sympathy as the fact of human nature lying at the basis of all social life and personal happiness. Defining morality as those qualities that are approved (1) in whomsoever they happen to be and (2) by virtually everybody, he sets himself to discover the broadest grounds of the approvals. He finds them, as he found the grounds of belief, in “feelings,” not in “knowings.” Moral decisions are grounded in moral sentiment. Qualities are valued either for their utility or for their agreeableness, in each case either to their owners or to others. Hume’s moral system aims at the happiness of others (without any such formula as “the greatest happiness of the greatest number”) and at the happiness of self. But regard for others accounts for the greater part of morality. His emphasis is on altruism: the moral sentiments that he claims to find in human beings, he traces, for the most part, to a sentiment for and a sympathy with one’s fellows. It is human nature, he holds, to laugh with the laughing and to grieve with the grieved and to seek the good of others as well as one’s own. Two years after the Enquiry was published, Hume confessed, “I have a partiality for that work”; and at the end of his life he judged it “of all my writings incomparably the best.” Such statements, along with other indications in his later writings, make it possible to suspect that he regarded his moral doctrine as his major work. He here writes as a man having the same commitment to duty as his fellows. The traditional view that he was a detached scoffer is deeply wrong: he was skeptical not of morality but of much theorizing about it.

Following the publication of these works, Hume spent several years (1751–63) in Edinburgh, with two breaks in London. An attempt was made to get him appointed as successor to Adam Smith, the Scottish economist (later to be his close friend), in the chair of logic at Glasgow, but the rumour of atheism prevailed again. In 1752, however, Hume was made keeper of the Advocates’ Library at Edinburgh. There, “master of 30,000 volumes,” he could indulge a desire of some years to turn to historical writing. His History of England, extending from Caesar’s invasion to 1688, came out in six quarto volumes between 1754 and 1762, preceded by Political Discourses (1752). His recent writings had begun to make him known, but these two brought him fame, abroad as well as at home. He also wrote Four Dissertations (1757), which he regarded as a trifle, although it included a rewriting of Book II of the Treatise (completing his purged restatement of this work) and a brilliant study of “the natural history of religion.” In 1762 James Boswell, the biographer of Samuel Johnson, called Hume “the greatest writer in Britain,” and the Roman Catholic Church, in 1761, recognized his philosophical and literary contributions by putting all his writings on the Index Librorum Prohibitorum, its list of forbidden books.

The most colourful episode of his life ensued: in 1763 he left England to become secretary to the British embassy in Paris under the Earl of Hertford. The society of Paris accepted him, despite his ungainly figure and gauche manner. He was honoured as eminent in breadth of learning, in acuteness of thought, and in elegance of pen and was taken to heart for his simple goodness and cheerfulness. The salons threw open their doors to him, and he was warmly welcomed by all. For four months in 1765 he acted as chargé d’affaires at the embassy. When he returned to London at the beginning of 1766 (to become, a year later, undersecretary of state), he brought Jean-Jacques Rousseau, the Swiss-born philosopher connected with the Encyclopédie of Denis Diderot and d’Alembert, with him and found him a refuge from persecution in a country house at Wootton in Staffordshire. This tormented genius suspected a plot, took secret flight back to France, and spread a report of Hume’s bad faith. Hume was partly stung and partly persuaded into publishing the relevant correspondence between them with a connecting narrative (A Concise and Genuine Account of the Dispute Between Mr. Hume and Mr. Rousseau, 1766).

In 1769, somewhat tired of public life and of England too, he again established a residence in his beloved Edinburgh, deeply enjoying the company—at once intellectual and convivial—of friends old and new (he never married), as well as revising the text of his writings. He issued five further editions of his History between 1762 and 1773 as well as eight editions of his collected writings (omitting the Treatise, History, and ephemera) under the title Essays and Treatises between 1753 and 1772, besides preparing the final edition of this collection, which appeared posthumously (1777), and Dialogues Concerning Natural Religion, in which he refuted the cosmological and teleological arguments for the existence of God (held back under pressure from friends, it was published posthumously in 1779). His curiously detached autobiography, The Life of David Hume, Esquire, Written by Himself (1777; the title is his own), is dated April 18, 1776. He died in his Edinburgh house after a long illness and was buried on Calton Hill.

Adam Smith, his literary executor, added to the Life a letter that concludes with his judgment on his friend as “approaching as nearly to the idea of a perfectly wise and virtuous man as perhaps the nature of human frailty will permit.” His distinguished friends, with ministers of religion among them, certainly admired and loved him, and there were younger men indebted either to his influence or to his pocket. The mob had heard only that he was an atheist and simply wondered how such an ogre would manage his dying. Yet Boswell has recounted, in a passage in his Private Papers, that, when he visited Hume in his last illness, the philosopher put up a lively, cheerful defense of his disbelief in immortality.

Significance And Influence

That Hume was one of the major figures of his century can hardly be doubted. So his contemporaries thought, and his achievement, as seen in historical perspective, confirms that judgment, though with a shift of emphasis. Some of the reasons for the assessment may be given under four heads:

As a writer

Hume’s style was praised in his lifetime and has often been praised since. It exemplifies the classical standards of his day. It lacks individuality and colour, for he was always proudly on guard against his emotions. The touch is light, except on slight subjects, where it is rather heavy. Yet in his philosophical works he gives an unsought pleasure. Here his detachment, levelness (all on one plane), smoothness, and daylight clearness are proper merits. It is as one of the best writers of scientific prose in English that he stands in the history of style.

As a historian

Between his death and 1894, there were at least 50 editions of his History; and an abridgment, The Student’s Hume (1859; often reprinted), remained in common use for 50 years. Although now outdated, Hume’s History must be regarded as an event of cultural importance. In its own day, moreover, it was an innovation, soaring high above its very few predecessors. It was fuller and set a higher standard of impartiality. His History of England not only traced the deeds of kings and statesmen but also displayed the intellectual interests of the educated citizens—as may be seen, for instance, in the pages on literature and science under the Commonwealth at the end of Chapter 3 and under James II at the end of Chapter 2. It was unprecedentedly readable, in structure as well as in phrasing. Persons and events were woven into causal patterns that furnished a narrative with the goals and resting points of recurrent climaxes. That was to be the plan of future history books for the general reader.

As an economist

Hume steps forward as an economist in the Political Discourses, which were incorporated in Essays and Treatises as Part II of Essays, Moral and Political. How far he influenced Adam Smith remains uncertain: they had broadly similar principles, and both had the excellent habit of illustrating and supporting these from history. He did not formulate a complete system of economic theory, as did Smith in his Wealth of Nations, but Hume introduced several of the new ideas around which the “classical economics” of the 18th century was built. His level of insight can be gathered from his main contentions: that wealth consists not of money but of commodities; that the amount of money in circulation should be kept related to the amount of goods in the market (two points made by the Anglo-Irish philosopher George Berkeley); that a low rate of interest is a symptom not of superabundance of money but of booming trade; that no nation can go on exporting only for bullion; that each nation has special advantages of raw materials, climate, and skill, so that a free interchange of products (with some exceptions) is mutually beneficial; and that poor nations impoverish the rest just because they do not produce enough to be able to take much part in that exchange. He welcomed advance beyond an agricultural to an industrial economy as a precondition of any but the barer forms of civilization.

As a philosopher

Hume conceived of philosophy as the inductive science of human nature, and he concluded that humans are creatures more of sensitive and practical sentiment than of reason. For many philosophers and historians his importance lies in the fact that Immanuel Kant conceived his critical philosophy in direct reaction to Hume (Kant said that Hume had awakened him from his “dogmatic slumber”). Hume was one of the influences that led Auguste Comte, the 19th-century French mathematician and sociologist, to develop positivism. In Britain Hume’s positive influence is seen in Jeremy Bentham, the early 19th-century jurist and philosopher, who was moved to utilitarianism (the moral theory that right conduct should be determined by the usefulness of its consequences) by Book III of the Treatise, and more extensively in John Stuart Mill, the philosopher and economist who lived later in the 19th century.

In throwing doubt on the assumption of a necessary link between cause and effect, Hume was the first philosopher of the postmedieval world to reformulate the skepticism of the ancients. His reformulation, moreover, was carried out in a new and compelling way. Although he admired Newton, Hume’s subtle undermining of causality called in question the philosophical basis of Newton’s science as a way of looking at the world, inasmuch as that science rested on the identification of a few fundamental causal laws that govern the universe. As a result, the positivists of the 19th century were obliged to wrestle with Hume’s questioning of causality if they were to succeed in their aim of making science the central framework of human thought.

For much of the 20th century it was Hume’s naturalism rather than his skepticism that attracted attention, chiefly among analytic philosophers. Hume’s naturalism lies in his belief that philosophical justification could be rooted only in regularities of the natural world. The attraction of that contention for analytic philosophers was that it seemed to provide a solution to the problems arising from the skeptical tradition that Hume himself, in his other philosophical role, had done so much to reinvigorate.