It was originally published in 1751, three years after the first Enquiry.[1] Hume first discusses ethics in A Treatise of Human Nature (in Book 3 - "Of Morals"). He later extracted and expounded upon the ideas he proposed there in his second Enquiry. In his short autobiographical work, My Own Life (1776), Hume states that his second Enquiry is "of all my writings, historical, philosophical, or literary, incomparably the best."