This book presents the Proceedings of the Second International Colloquium on Cognitive Science, held at San Sebastian in May, 1991, to discuss from an interdisciplinary point of view topics which are at the intersection of philosophy and cognitive science. With a total of eleven papers from leading scholars in the field, the volume provides many different theoretical approaches to the study of Categories, Consciousness and Reasoning. The book is addressed to researchers, specialists, advanced students and scholars in the fields of epistemology, philosophy of mind, psychology, semantics, logic and artificial intelligence.