Susan Haack

Susan Haack (England, 1945 – Miami, 2026) was a British philosopher who taught for much of her career at the University of Miami, where she also held a professorship in law. Her work covers logic, the philosophy of language, epistemology and metaphysics. Her pragmatism grew out of the thought of Charles Sanders Peirce, but she developed a position of her own and was often critical of other readings of pragmatism.

She studied at Oxford, at St. Hilda's College, where her first philosophy teacher was Jean Austin, the widow of J. L. Austin. There she studied Plato with Gilbert Ryle and logic with Michael Dummett. David Pears supervised her B.Phil. dissertation on ambiguity, and at Cambridge she completed her PhD under Timothy Smiley. She was a Fellow of New Hall, Cambridge, and a professor at the University of Warwick before joining Miami. Her best-known books include Deviant Logic (1974), Evidence and Inquiry (1993), Manifesto of a Passionate Moderate (1997) and Defending Science – Within Reason (2003).

Her most influential contribution is foundherentism, set out in Evidence and Inquiry. It tries to avoid both the infinite regress of pure foundationalism and the circularity of pure coherentism. She explained it with the image of a crossword: finding a word from its clue is like a foundational source grounded in empirical evidence, while checking that the interlocking words make sense together corresponds to justification through coherence. Both are needed to justify knowledge.

In the philosophy of science she defended a moderate position, between scientism and cynicism. She argued that inquiry rests on good evidence, sound methods and open review, and that the institutions of science make it reliable without turning it into the monopoly of experts. She criticised the idea of a distinctively female perspective on logic or scientific truth, and she debated Richard Rorty, whose claim to be a pragmatist she challenged. She wrote for Free Inquiry magazine and was a past president of the Charles S. Peirce Society.

Her work has been cited in academic journals and reviewed in the press, including The Times Literary Supplement. Her defence of a rigorous pragmatism and a non-dogmatic epistemology keeps her a reference point in debates on the philosophy of science and of law. She died in Miami in March 2026, at the age of 80.