Wolfgang Pauli was not only a Nobel laureate and one of the creators of modern physics, but also an eminent philosopher of modern science. In his essays he writes about space, time and causality, symmetry and the exclusion principle, but also about the role of the unconscious in modern science. His famous article on Kepler is included as well as essays on Bohr, Ehrenfest, Einstein, and Sommerfeld. This is the first book in English to include all articles on physics and philosophy.