Richard Maurice Bucke (18 March 1837 - 19 February 1902), often called Maurice Bucke, was a prominent Canadian psychiatrist in the late 19th century. An adventurer during his youth, Bucke later studied medicine. Eventually, as a psychiatrist, he headed the provincial Asylum for the Insane in London, Ontario. Bucke was a friend of several noted men of letters in Canada, the United States, and England. Besides publishing professional articles, Bucke wrote three books: Man's Moral Nature, Walt Whitman, and Cosmic Consciousness: A Study in the Evolution of the Human Mind, which is his best-known work.