A great deal of interest and excitement surround the interface between the philosophy of biology and the philosophy of psychology, yet the area is neither well defined nor well represented in mainstream philosophical publications. This book is perhaps the first to open a dialogue between the two disciplines. Its aim is to broaden the traditional subject matter of the philosophy of biology while informing the philosophy of psychology of relevant biological constraints and insights.The book is organized around six themes: functions and teleology, evolutionary psychology, innateness, philosophy of mind, philosophy of science, and parallels between philosophy of biology and philosophy of mind. Throughout, one finds overlapping areas of study, larger philosophical implications, and even larger conceptual ties. Woven through these connections are shared concerns about the status of semantics, scientific law, evolution and adaptation, and cognition in general.