A Treatise of Human Nature

In the Treatise of Human Nature, written in 1739, David Hume lays out his initial vision of our knowledge and understanding of the world, of the nature of our psychology and motivation, and, building on these, of moral and political philosophy.

In Book I, Hume considers our understanding of the world. With a keen critical perspective that is ever skeptical about abstract metaphysical claims, he follows other empiricists (such as Locke) in grounding our understanding in experience as the source of all our ideas and of their relations to each other. In one important line of argument, he raises what has come to be known as his “problem of induction” at the heart of our understanding of causation and of science, arguing that we have no reason to think that the future will be like the past, since our only evidence for that claim could be past experience—a problem that has plagued philosophers ever since.

In Book II, Hume turns from belief and reason to desire and the passions, famously arguing that “it is not contrary to reason to prefer the destruction of the whole world to the scratching of my finger”—that questions of what we ought to desire or value are not questions we can settle by appealing to beliefs and arguments. Rather, our desires and passions can be independent of our beliefs, so that values aren’t a part of the world, but are projected by us onto the world.

In Book III, Hume spells out the implications this view has for morality, and so for moral values and moral taste. In doing so, he emphasizes our sympathy for others and the need for us to use that sympathy so as to adopt “steady and general points of view” as the proper vantage point for engaging in moral criticism.

The Treatise was poorly received, with Hume himself writing that it fell “deadborn from the press.” He thought it an immature work, written as it was before he was 25 years old, and he later reworked his account from Book I in his Enquiry Concerning Human Understanding and from Book III in his Enquiry Concerning the Principles of Morals. Nonetheless, much of Hume’s dissatisfaction seems to be stylistic rather than substantive; philosophical scholarship has tended to focus on the Treatise over his other works, and it has remained highly influential to this day, shaping important strands of thought in philosophy and psychology.