An Essay Concerning Humane Understanding, Volume II

A landmark of Enlightenment thought, Hume's An Enquiry Concerning Human Understanding is accompanied here by two shorter works that shed light on it: A Letter from a Gentleman to His Friend in Edinburgh, Hume's response to those accusing him of atheism, of advocating extreme skepticism, and of undermining the foundations of morality; and his Abstract of A Treatise of Human Nature, which anticipates discussions developed in the Enquiry.

An Enquiry Concerning Human Understanding is a revision of an earlier Hume's work, Treatise of Human Nature, published anonymously in London in 1739–40. Hume was disappointed with the reception of the Treatise, which "fell dead-born from the press," as he put it, and so tried again to disseminate his more developed ideas to the public by writing a shorter and more polemical work.