My research centers on the philosophy of science and its history, especially on scientific experiment, theory building and development, semantics, and related issues in epistemology. My current projects include work on the physics of gravitational waves and the methods of advanced LIGO, and on mathematical methods in physics more generally. Past work focuses on the use of signs and axioms in scientific inference, on the history of 19th century science and philosophy, and on Kant's philosophy as a response to empiricism and rationalism. More at