The 100 Best nonfiction books: No 87 - A Treatise of Human Nature by David Hume (1739)

The career of the Scottish philosopher David Hume is a parable of the writing life that speaks with eloquence about the strange and inexplicable progress of ideas in the marketplace of free debate. His career, moreover, is one that runs almost to the day he died, in 1776, just after the outbreak of the American revolution.

Hume was born and educated in Edinburgh, the son of a successful lawyer, and acquired a fierce appetite for philosophy at a precociously young age. After a mental breakdown as a student, and despite limited personal means, he spent three years of private study in France. Thereafter, he worked for four years on A Treatise of Human Nature. It was his first major work as a philosopher, and it bore the unwieldy subtitle “Being an Attempt to Introduce the Experimental Method of Reasoning into Moral Subjects”.Hume completed Treatise in 1738, aged 28, and published it anonymously in two volumes the following year.

His ambitious intention was to construct a pragmatic science of man, a wholesale system of thought by which to appraise the psychological basis of human nature. In opposition to the rationalists of the day, Hume argued that it was passion rather than reason that moderates human behaviour: “Reason is, and ought only to be the slave of the passions, and can never pretend to any other office than to serve and obey them.”

From this position, Hume advanced the idea that human knowledge must ultimately be located in mankind’s quotidian experience. “It is not contrary to reason to prefer the destruction of the whole world to the scratching of my finger,” he wrote.

The publication of Hume’s Treatise was a disaster. Its wit and clarity (“Poets… though liars by profession, always endeavour to give an air of truth to their fictions”) were overlooked; his majestic philosophical rigour misunderstood. He himself later observed that it “fell dead-born from the press”. Today, however, Treatise is widely considered to be Hume’s most important work, one of the keystone books of western philosophy, in the words of one commentator, “the founding document of cognitive science” and possibly the “most important philosophical work” in the English language.

In 1740, however, the critics were savage, describing his work as “abstract and unintelligible”. It’s not hard to see why. Even today, the Treatise is notably dry, and makes few concessions to the reader.

Organised in three parts (Of the Understanding, Of the Passions and Of Morals), with many sub-sections such as “Of Ideas, Their Origin, Composition, Connexion, Abstraction, Etc.”; “Of the Ideas of Space and Time”; “Of Knowledge and Probability” and “Of the Sceptical and Other Systems of Philosophy Etc”, it concludes with a recapitulation with Hume’s reasoning for his thesis that “sympathy is the chief source of moral distinctions”.

As the first reviews suggest, the Treatise is not for the faint-hearted. This passage is typical: “After the most accurate examination of which I am capable, I venture to affirm that the rule here holds without any exception, and that every simple idea has a simple impression, which resembles it, and every simple impression a correspondent idea.”

Hume did not repine. He had devoted most of his savings to the long gestation of the work, and he would not give up. Addressing his restricted circumstances, he declared that he would dedicate himself to literature. He would, he wrote, “make a very rigid frugality supply my deficiency of fortune, to maintain unimpaired my independency”. With stoic self-belief he pronounced “every object contemptible except the improvements of my talents in literature”. And so, despite his bad press, and the frustration of his youthful ambition, Hume concluded: “Being naturally of a cheerful temper, I soon recovered from the blow and prosecuted with great ardour my studies in the country.”

With impressive sang froid, having determined that the problem with the Treatise was one of style not content, Hume reworked his material into two rather more accessible essays entitled An Enquiry Concerning Human Understanding (1748) and An Enquiry Concerning the Principles of Morals (1751). These, Hume wrote, with typical brio, were “of all my writings, historical, philosophical, or literary, incomparably the best”. Next, in 1752, he published his Political Discourses, which was translated into French and made Hume famous throughout Europe. Now on a roll, in 1754 he published the brilliant first volume of his History of Great Britain, a narrative largely devoted to the early Stuart kings followed by further volumes in 1757, 1759, and 1762.

Always a great stylist, Hume was now established as one of the great intellects of his time, a cultural icon, renowned as much in London as in Scotland. Forever in search of new kinds of self-expression, at the end of his life, and conscious that he was dying, Hume published a short autobiographical essay on “My Own Life” in which he summarised his entire life in “fewer than 5 pages” – a genre that almost amounts to a private joke, being notably short on personal anecdote and standard autobiographical data. Dry as ever, he writes dispassionately of his imminent decease: “I now reckon upon a speedy dissolution. I have suffered very little pain from my disorder, and what is more strange, notwithstanding the great decline of my person, never suffered a moment’s abatement of my spirits.”

However, Hume did confess that a “love of literary fame” had served as his “ruling passion” in life. With his usual self-confidence, he claimed that this ambition “never soured my temper, notwithstanding my frequent disappointments”. The reception of the Treatise was one of these, he admitted, but the success of his subsequent Essays had preserved his good spirits. “That work was favourably received, and soon made me entirely forget my former disappointment,” he said.

In a line that many contemporary writers might profitably take to heart, he observed, of the Treatise, that his philosophical debut’s immediate failure “had proceeded more from the manner than the matter”. Hume explained his meaning thus: “I had been guilty of a very usual indiscretion, in going to the press too early.”

A signature sentence

“In every system of morality, which I have hitherto met with, I have always remarked that the author proceeds for some time in the ordinary way of reasoning, and establishes the being of a god, or makes observations concerning human affairs; when of a sudden I am surprized [sic] to find that instead of the usual copulations of proposition, is and is not, I meet with no proposition that is not connected with an ought or an ought not; this change is imperceptible, but it is, however, of the last consequence.”

Three to compare

Thomas Hobbes: Leviathan (1651)

John Locke: An Essay Concerning Human Understanding (1689)

David Hume: History of Great Britain (1754)

• A Treatise of Human Nature by David Hume is published by Penguin Classics (£14.99). To order a copy for £12.74 go to guardianbookshop.com or call 0330 333 6846. Free UK p&p over £10, online orders only. Phone orders min p&p of £1.99