Source, in full
"A Reply to Professor Haldane" (1946), published posthumously in Of Other Worlds: Essays and Stories (1966). Written in response to "Auld Hornie, F.R.S." by J. B. S. Haldane, a review of the Space Trilogy. Some of these ideas were included in the essay "The Humanitarian Theory of Punishment" (1949) (see below). "Aristotle's canon" is given in Nichomachean Ethics, Book I, 1094b.24