Cora Diamond (born 1937)^[2] is an American philosopher who works in the areas of moral philosophy, animal ethics, political philosophy, philosophy of language, philosophy and literature, and the thought of Ludwig Wittgenstein, Gottlob Frege, and Elizabeth Anscombe. Diamond is the Kenan Professor of Philosophy Emerita at the University of Virginia.

Diamond received her Bachelor of Arts degree from Swarthmore College in 1957 and her Bachelor of Philosophy degree from St Hugh's College, Oxford (where her tutor was Paul Grice^{[citation needed]}), in 1961. She was elected to the American Academy of Arts and Sciences in 2024.^[3]

One of Diamond's most famous articles, "What Nonsense Might Be", criticizes the way that the logical positivists think about nonsense on Fregean grounds (see category mistake). Another well-known article, "Eating Meat and Eating People", examines the rhetorical and philosophical nature of contemporary attitudes towards animal rights. Diamond's writings on both "early" (Tractatus Logico-Philosophicus era) and "late" (Philosophical Investigations era) Wittgenstein have made her a leading influence in the New Wittgensteinian approach advanced by Alice Crary, James F. Conant, and others.

Diamond has published a collection of essays titled The Realistic Spirit: Wittgenstein, Philosophy, and the Mind. She is the editor of Wittgenstein's Lectures on the Foundations of Mathematics: Cambridge 1939, a collection of lectures assembled from the notes of Wittgenstein's students Norman Malcolm, Rush Rhees, Yorick Smythies, and R. G. Bosanquet.

Wittgenstein and the Moral Life: Essays in Honor of Cora Diamond (edited by Alice Crary^[4]) features essays by Crary, John McDowell, Martha Nussbaum, Stanley Cavell, and James F. Conant, among others.

• American philosophy