This series includes monographs and collections of studies devoted to the investigation and exploration of knowledge, information, and data-processing systems of all kinds, no matter whether human, (other) animal, or machine. Its scope spans the full range of interests from classical problems in the philosophy of mind and philosophical psychology through issues in cognitive psychology and sociobiology (concerning the mental powers of other species) to ideas related to artificial intelligence and computer science. While primary emphasis is placed upon theoretical, conceptual, and epistemological aspects of these problems and domains, empirical, experimental, and methodological studies will also appear from time to time. This multi-authored volume provides investigations that fall into three broad areas of inquiry. In Part I, Antti Revonsuo reviews and evaluates contem porary discussions of the nature of consciousness. In Part II, Matti Kamppinen explores methodological issues, distinguishing between "intentional" and "structural" explanations. In Part III, Seppo Sajama and Simo Vihjanen consider whether humans ever have direct access to reality (in Section A), while Matti Kamppinen and Antti Revonsuo explore the conse quences of the claim that our knowledge of reality is conceptually mediated (in Section B). These studies combine to provide a stimulating exploration of cognitive science that should appeal to students and to scholars alike. J.H.F. vii PREFACE BY THE EDITOR The purpose of the book is to illustrate how empirical and conceptual problems interact in modem cognitive science. We argue that several topics discussed in contemporary research have long historical roots in philosophy.