HUME, DAVID. - Philosopher, b. 26 Apr. 1711 at Ninewells (southern Scotland), d. at Edinburgh 25 Aug. 1776. He studied at the University of Edinburgh, the ancient capital of Scotland, first, to comply with his family's wish, jurisprudence; then he turned decisively to the study of philosophy and of the classical authors, of Cicero and Seneca above all. These were the years in which the philosophical work of Locke and Berkeley concentrated general attention, and the young Scot was seized by a powerful ambition to enter the discussion and to place his name alongside that of the Englishman and the Irishman. While his plan was maturing, in order to broaden the horizon of his views, he devoted himself, for some years, to traveling. Naturally Paris, which was then the great center of the most revolutionary ideas, attracted him more than any other city; and there, from 1734 to 1738, he drafted his Treatise of human nature (London 1739-40), which is his major work, and from which he later derived, with reworkings and elaborations, the others concerning the same subject. The treatise bore as its subtitle: An attempt to introduce the experimental method of reasoning into moral subjects (it was the method, then much acclaimed, of Newton), and it was divided into three parts: Of the understanding; Of the passions; Of morals. Meanwhile, he had returned to his homeland, where he believed he had secured with the published work the renown he was due. The success, instead, was mediocre. Moreover, the radically skeptical attitude that he had assumed in it could certainly not win him the favor of official science, so it is no wonder that the University of Edinburgh, to which he applied for a chair, denied it to him. In the meantime he had published in 2 vols. Essays moral political and literary (1741-42), which, also because of the form more accessible to people of general culture, had met with better fortune among the public. There followed some years in which he sought, but in vain, a position, at home or abroad. In 1748 he published An enquiry concerning human understanding, which presented anew, in a form also more attractive literarily, the capital thesis of the first book of the Treatise. There followed in 1751 the Enquiry concerning the principles of morals, which reworked the third book of the same Treatise. In 1752 his Political discourses came out.
Meanwhile he had settled into a position as librarian, where he had the opportunity to devote himself to a vast work, the History of England from the invasion of Julius Caesar to the revolution of 1688, published, in various installments, between 1754 and 1771. In the meantime he continued his philosophical studies, publishing in 1757 Four dissertations, of which the first and most important was The natural history of religion. Later he wrote the Dialogues concerning natural religion, which, however, he did not deem it prudent to publish (they appeared posthumously in 1779). Also the two essays Of suicide and Of the immortality of the soul, which originally formed part of the Four dissertations, appeared, anonymously, only in 1777. His fame was by now assured. Hence, when in 1763 he went to Paris as secretary of legation, he was received enthusiastically. There he enjoyed the friendship of the great writers and thinkers of the time, of Voltaire and of Rousseau. With the latter, moreover, because of his well-known extravagant character, he had a sensational incident (which H. wished to set before the public, to demonstrate his own correctness, in a printed pamphlet). In 1767 he took part in affairs of State as undersecretary at the Ministry of Foreign Affairs. But in 1768 he resigned and retired to his Edinburgh. He lived his last years among few friends and many books. After a long illness he passed away on 25 Aug. 1776.
The undoubtedly most important work of H. is the Treatise, and of this the fundamental part is I. I, which contains the critique of the epistemological principle posited by Locke and developed by Berkeley. This is the masterpiece of modern skepticism: critical skepticism, that is, conducted with rigorous method, in which H. revealed his destructive genius. It must be noted, however, that the value of this critique is limited to the initial assumption from which it starts, which is that of an empiricism understood as a subjectivism founded on the immediate act of sensation. So that the result of this skepticism, at least in this respect, has been exceedingly beneficial, in that it forced philosophy to abandon such a position. As is well known, the first to feel this beneficial effect was E. Kant, who, however, came from another school, from the Wolffian one, in which an attempt had been made at a reconciliation between empiricism and rationalism.
The decisive point of Hume's critique is that of the distinction between the act of sensing-perceiving, which here is defined as impression (in order to grasp it in its most immediate reality), and the idea. This is a reflection posterior to the act, when the sensation has already passed into memory, and is, therefore, far less vivid and evident than the impression grasped in its actuality. Thus the whole edifice of ideas collapses, with which, believing they could legitimately derive them from the act of perceiving, both Locke and Berkeley had sought to explain the world of experience. Another distinction, fundamental to Lockean-Berkeleian empiricism, was that of external and internal experience: H. maintained that the impression, in its actuality, did not admit the distinction of an external from an internal, of an objective from a subjective.
Having laid down these principles, the author's aim now becomes to demonstrate the vanity of every idea, or notion (as he habitually calls it), not derived from an impression; and, at the same time, to replace it with an idea more conformable and adequate to the impression into which it must be resolved. The book thus becomes a critical treatment of the whole world of ideas, with which philosophers undertook to explain the world of experience. Capital in this treatment is the work of the imagination, which is now the faculty of ideas, the one that elaborates them and unites them in relations in order to construct a genuine knowledge comprising, beyond past experience, also future experience. Note that, to explain these relations, H. supposes that the original impression is equivalent to a bundle of impressions, from which the first, concrete ideas would derive, which by a natural law (one may think of Newton's universal attraction) associate in such a way that the mind is driven, as by an unnoticed force, to pass from one to the other. The laws of this association are three: by resemblance, by contiguity, by causality. Here the principle of habit (custom) makes its appearance, and of the tendency to pass from what we currently perceive to what, having perceived it in the past together with the other, we expect to perceive again. Hence that feeling of expectation and confidence that H. calls belief.
This is the first part of the book. The second contains the celebrated critique of the ideas of space and time. Space and time reveal themselves not as impressions (there being no specific organ for them), but as relations or modes of presenting themselves of impressions (in the original impression). Space, in fact, is coexistence, time is succession of impressions: relations, therefore, not "things," not a reality objectively existing. The reality, for example, of the mathematical point is in the idea corresponding to the impression of a minimum of perceptibility (a grain of sand, for example). Hence the devaluation of mathematics, in that the exactness and rigor of which they boast, if their ideas are brought back to the concreteness of experience, reveal themselves as mere approximations.
In the third part the famous critique of the idea of causality predominates (this is also the part later taken up and developed in the subsequent work, in the Enquiry, which, as has been said, enjoyed greater renown for a long time both before and after Kant). The maxim accepted in metaphysics, according to which "everything that begins to exist must have a cause of its existence," brought back to the ground of experience from which it originated, plainly reveals its flaw: it lays claim to a necessity that, in concrete terms, is never demonstrable: it is at most a constancy hitherto experienced in the succession of two facts: never a true and proper necessity, by which, as in logic, the contrary would be excluded. And in this constancy we trust that what we have observed up to now will continue to exist in the same way in the future. Thus, in the ruin of the principle of causality, the foundation of the experimental sciences as such was swept away.
In the fourth and final part, the most general conclusions of the preceding critique are, in a certain sense, gathered together, applying them both to ancient and to modern philosophy. Indeed, both the objectivism of the one and the subjectivism of the other are combated. If the ideas of substance, of identity, etc., prove in the end to be mere fictions of the imagination, without a real foundation, what remains of what we call the "object," and of what we call the "subject"? Nothing concrete. Existence, too, is an abstract idea, insofar as it presupposes those just mentioned. In the end, the act remains alone with itself: a bundle of sensations, an impression of impressions, a series and a flowing of acts, which permit us to affirm nothing about reality, not even about themselves. Absolute skepticism, mitigated only by that sentiment which, in the philosopher no less than in the common man, follows the spontaneous course of thought, and gives him a faith in reality sufficient for the needs of his life.
In the moral problem as well, H. attaches himself to the work of his predecessors, to the school of the English moralists, who in the innate and spontaneous "moral sense" had sought to save the principle of morality from the destructive criticism of rationalism. "Reasoning reason" has no power, in itself, to move man to action: passion, sentiment, is needed. On the other hand, sentiment is not enough for morality, if it is limited to one's own well-being, to one's own utility (selfish system): a higher sentiment is needed. Along this path, opened by Shaftesbury, Hutcheson and Butler had set out: H. continues their work with a more acute and precise critique, and determines the principle of the moral conscience as a sentiment of sympathy, by which we feel "naturally" pleasure or pain together with the pleasure or pain of others (similarly, he says, to the movement of one string that is communicated to the others equally taut). A principle of social life, this, which is then consolidated in the further sentiment of justice, by which we come to judge the value of an action independently of any present pleasure or personal interest: that is, to love the humanity of man in every man. This principle of sympathy was later developed by A. Smith: it was, however, still susceptible of a utilitarian interpretation, as was seen with Bentham (v.).
Where, instead, H.'s skeptical mentality reappears with all its destructive force is in the philosophy of religion. Here, not only Christianity, but also that minimum of religion that one wished to save with the idea, adopted by deism (v.), of a "natural religion," are undermined at the root. In the Dialogues the a posteriori proofs of the existence of God, the cosmological and the teleological, are combated with arguments that already prelude those of Kant. Added to this is the critique of the moral argument, insisting on the fact of evil that is in the world, whereby its principle cannot be goodness. In the Natural History of Religion the principle of the religious sentiment is positively sought, and it is placed, in a Lucretian manner, in the terror of death, in the fear of unhappiness, in the desire and anxiety for well-being. Polytheism is, for H., the first and most genuine form of the religious sentiment of humanity in general, and from it, not from abstract or philosophical reason, the monotheistic idea later emerges, which, although it seems superior through the work of reflection, then shows itself, with its intolerance, inferior to polytheism. In any case, in the conflict of faiths, H. sees only a struggle of superstitions: and he withdraws again, in Enlightenment fashion, "into the calm, though obscure, regions of philosophy." (v. also CAUSA; SCETTICISMO).
All of H.'s works are on the Index with the expression opera omnia, decr. 19 Jan. 1761, 10 Sept. 1827.