I am a philosopher with an extensive interest and background in natural science. I have a B.A. in mathematics from the University of California (Santa Barbara) and a Ph.D. in philosophy from Brown University. My current position is Full Professor of Philosophy at the University of Colorado (Boulder).

Before I became a philosopher, I was a software engineer. After receiving my Ph.D. in philosophy, I spent a year (1985-86) on a postdoctoral fellowship in philosophy and computer science at Stanford University’s Center for the Study of Language and Information (CSLI). I am a member of the NASA Astrobiology Institute (NAI) and a Co-I in the Center for Astrobiology at the University of Colorado.

My research is focused in the areas of philosophy of science, philosophy of logic and metaphysics. I am particularly interested in historical science, astrobiology, the theory of computation, and the nature of causation. I have written articles on causation, space and time, supervenience, events, standards of evidence in science, the methodology of historical and experimental science, the problem of defining ‘life’, the Church-Turing thesis, effective procedures, and hypercomputation

I enjoy teaching and sharing my work with others. I teach undergraduate and graduate students. I also frequently give presentations to scientists, journalists, high school classes, K-12 teachers, and to the general public.