Born in Edinburgh, his father died when he was 2, and Hume spent his childhood at Ninewells estate on the Whitadder River near Berwick, with his mother Katherine Falconer Hume, elder brother and sister. He was “uncommonly wake-minded” and joined his brother at Edinburgh University, aged only 11. But at 15 he sought “a more active scene of life” in commerce, as clerk for a Bristol sugar importer. He moved to France, to live frugally, and settled in La Flèche, in Anjou known for its Jesuit college, where Descartes and Mersenne studied a century before. Read Malebranche, Dubos, and Bayle, baited the Jesuits with iconoclastic arguments and, aged 23-26, drafted A Treatise of Human Nature. Published in England in three Books 1739-40.
To avoid prosecution he was persuaded to delete his controversial discussion of miracles and other “nobler parts”. Despite deletions it attracted enough “murmour among the zealots” to fuel his reputation as atheist and sceptic, sufficient to prevent him obtaining any academic post; among those he applied for were the Chair of Ethics at Edinburgh 1745 and of Logic at Glasgow 1752. He published two volumes of Essays in 1741-2. He became tutor to the Marquess of Annandale, only to find that the young man was insane and his estate manager dishonest. His cousin, Lt-Gen James St. Clair, invited him to be Secretary on a military expedition in Quebec, that ended as an abortive raid on the coastal town of L'Orient in Brittany. Hume also accompanied St. Clair on an extended diplomatic mission to the courts of Vienna and Turin in 1748.
While in Italy, his Essays Concerning Human Understanding appeared. A recasting of Book I of the Treatise. He wrote to his friend Gilbert Elliot of Minto that “the philosophical principles are the same in both … by shortening and simplifying the questions, I really render them much more complete”. And in “My Own Life,” he added that the Treatise's lack of success “proceeded more from the manner than the matter.” In 1751 the Enquiry Concerning the Principles of Morals a rewritten version of Book III of the Treatise appeared. Political Discourses 1752 and draft of Dialogues Concerning Natural Religion was well underway.
As Librarian to Edinburgh Faculty of Advocates Hume found opportunity to work on History of England. Six volumes 1754, 1756, 1759, 1762, whch became a best-seller, giving him financial independence. However in 1754, his order described as for several “indecent Books unworthy of a place in a learned Library” led to a move for his dismissal and in 1756 there was an unsuccessful attempt to excommunicate him. The Library's Trustees cancelled his order. He turned over his salary to Thomas Blacklock, a blind poet he befriended and sponsored, and resigned to make the position available for Adam Ferguson.
In 1755, he was ready to publish The Natural History of Religion and Dissertation on the Passions as well as the essays “Of Suicide” and “Of the Immortality of the Soul.” His publisher, Andrew Millar, was threatened with legal action through machinations of theologian, William Warburton.
In 1763, Hume accepted an invitation from Lord Hertford, the Ambassador to France, to serve as his Private Secretary. During his three years in Paris, Hume became Secretary to the Embassy and eventually its Chargè d'Affaires. He also become the rage of the Parisian salons, enjoying company of Diderot, D'Alembert, and d'Holbach. as well as the attentions and affections of the salonnières, especially the Comtesse de Boufflers. Hume returned to England in 1766, accompanied by Jean-Jacques Rousseau, who was fleeing persecution in Switzerland. Their friendship however ended when paranoid Rousseau thought Hume was masterminding a conspiracy against him.
After a year (1767-68) in London as an Under-Secretary of State, Hume returned to Edinburgh to stay in August, 1769. One young person who found his company “acceptable” was Nancy Orde, daughter of Baron Orde of the Scottish Exchequer. She chalked “St. David's Street” on the side of Hume's house one night; the street still bears that name today. Upon finding that he had intestinal cancer, Hume prepared for his death with peaceful cheer. He arranged for posthumous publication of the Dialogues Concerning Natural Religion. His works: On Human Nature (1739-1740), Human Understanding (1748), Morals (1751), and Religion (1779) remain influential. Charles Darwin counted Hume as a central influence, as did T. H. Huxley.
The Enquiry urges nothing less than the total reform of philosophy, abandoning the a priori search for theoretical explanations, replacing these “hypothes[es], which can never be made intelligible” with an empirical, descriptive inquiry that answers questions about “the science of human nature” in the only way they can be intelligibly answered. His aim is to bring about “a reformation in moral disquisitions” similar to that recently achieved in natural philosophy, where we have been cured of “a common source of illusion and mistake” — our “passion for hypotheses and systems.” [i.e. Newton - no hypothesizing without empirical basis] we should “reject every system … however subtle or ingenious, which is not founded on fact and observation,” and “hearken to no arguments but those which are derived from experience”.
Hume's species of philosophy looks at humans as active creatures, driven by desires and feelings and “influenced…by taste and sentiment” - in contrast to positions defended in Hume's time by Shaftesbury and Francis Hutcheson. Since this garbage won't degrade by itself, philosophers should “perceive the necessity of carrying the war into the most secret recesses of the enemy”. For Hume, all the materials of thinking — perceptions — are derived either from sensation (“outward sentiment”) or from reflection (“inward sentiment”). He divides perceptions into two categories, distinguished by their different degrees of force and vivacity. Our “more feeble” perceptions, ideas, are ultimately derived from our livelier impressions.
His account of definition is the most distinctive and innovative element of his system. Hume believes that “the chief obstacle … to our improvement in the moral or metaphysical sciences is the obscurity of the ideas, and ambiguity of the terms”. He argues that conventional definitions — defining terms in terms of other terms — replicate philosophical confusions by substituting synonyms for the original and thus never break out of a narrow “definitional circle”. Determining the cognitive content of an idea or term requires something else. To make progress, we need “to pass from words to the true and real subject of the controversy” — the ideas involved.
Belief or assent, which always attends the memory and senses, is nothing but the vivacity of those perceptions they present; and that this alone distinguishes them from the imagination. To believe is in this case to feel an immediate impression of the senses, or a repetition of that impression in the memory. “We form a kind of system” of these strong impressions of sense and memory. So although impressions are not, strictly speaking, capable of truth or falsity, the systematic character of the “universe of the imagination” gives us a means of accepting or rejecting impressions. The standard, roughly, is coherence.
A science of human nature should account for connections - ideas are “bound together”. His introduction of “principles of association”: resemblance, contiguity, and cause and effect. Of the three, causation is the strongest: It establishes a link or connection between past and present experiences with events that we predict or explain, so that “all reasonings concerning matter of fact seem to be founded on the relation of cause and effect.” With the addition of causation, Hume's “system” now extends beyond the immediate testimonies of our senses and the records of our memories, providing a much more extensive web of belief, and a more fine-grained mechanism for accepting or rejecting impressions on the basis of their coherence, or lack of it, with the whole.
Just as individual impressions are corrigible, the system as a whole is fallible, and thus fallibility is at the heart of what Hume in the first Enquiry calls “mitigated scepticism.” Modifying and — it is to be hoped — improving the system; a system allegedly built on more secure “foundations” — “principles” that go beyond perceptions and are somehow supposed to validate them — is a metaphysical pipe-dream, not the legitimate basis of a coherent account of human nature, judgment, and belief. Metaphysics tempts us to regard these answers as making claims about the ultimate nature of reality. Hume shows us how to resist that temptation.