Peter Unger, one of the world's most original and unorthodox philosophers, is a major contributor to metaphysics, epistemology, ethics, and philosophy of mind. A native New Yorker, for more than thirty years he has been a Professor of Philosophy at New York University. He is the author of Ignorance (OUP 1975, reissued 2002), Philosophical Relativity (1984, reissued by OUP 2002), Identity, Consciousness and Value (OUP 1990), Living High and Letting Die (OUP 1996), and forthcoming collections of his published philosophical papers (OUP, 2006).