This volume addresses the subject of categories: What are they? How are they used in speaking and thinking? What role do they play in our moral deliberations? Why are there different sorts of categories? And are categories independent of our thinking and speaking, giving objective form to the world we aim to think and speak about? These and other questions concerning categories have been part of philosophy from the very beginning, and they raise foundational issues in metaphysics, epistemology, ethics, and other branches of philosophy. Yet pursuing answers to these questions has proven...