Harry Gordon Frankfurt, Ph.D. (Philosophy, Johns Hopkins University, 1954; M.A., Johns Hopkins, 1953; B.A., Johns Hopkins, 1949), was a Professor of Philosophy Emeritus at Princeton University. He previously served as chair of the philosophy department at Yale University, 1978–1987, where he was also a lecturer in the School of Law, 1981–89. He was a Fellow of the American Academy of Arts and Sciences.