Philosophers of science work not only with the methods of the sciences but with their contents as well. Substantive issues concerning the relation between mind and matter, between the material basis and the functions of cognition, have been central within the entire history of philosophy. We recall such philosophers as Aristotle, Descartes, the early Kant, Ernst Mach, and the early William James as directly inquiring of the organs and structures of thinking. Science and its philosophical self-criticism are especially and deeply united in the effort to understand the biological brain and human...