Irwin, Terence H. (2000). Ethics as an inexact science: Aristotle's ambitions for moral theory. In Brad Hooker & Margaret Olivia Little (eds.), Moral particularism. New York: Oxford University Press. pp. 100-29. 4. Ethics and Variation When Aristotle claims that ethics provides usual generalizations, does he primarily have in mind mere frequencies or natural norms? Does he recognize ethical prin..