Thomas Piecha is a philosopher, physicist, and computer scientist. His research interests include proof-theoretic and dialogical approaches in logic, the logical writings of Karl Popper, and the logical and physical foundations of computer science. Kai Wehmeier is a professor of logic and philosophy of science at the University of California, Irvine. He has made contributions to mathematical and philosophical logic, formal semantics, the philosophy of language, and the history of analytic philosophy, with a special emphasis on Frege.