Linda Wetzel received her doctorate in philosophy from the Massachusetts Institute of Technology in 1984. Research interests include (1) metaphysics, (2) philosophy of mathematics,(3) philosophy of language; (4) philosophy of mind (5) philosophical logic; and (6) the philosophy of Gottlob Frege. Dr. Wetzel has taught at Tufts University and the University of Massachusetts at Amherst, and is currently Associate Professor of Philosophy and Director of Undergraduate Studies in Philosophy at Georgetown University. Her most recent work is a book in metaphysics, Types and Tokens: On Abstract Objects, on the relationship between the universals known as types and their instances.