this book exposes serious flaws in the reductionist assumptions about mind and matter of naturalism and constructivism, which underlie research and theorizing on cognition, language and action within current academic psychology. the author argues for alternative, radically different assumptions about the relationship between the mental and material reality, which are not only tenable, but as a matter of principle must be taken for granted, and be the point of departure for all investigations into both reality and our cognition and description of it. the consequences of the arguments in this book are far-reaching. the assumptions and principles derived from them offer a consistent foundation for a science of psychology. they also open up new and straightforward ways of dealing with the key issues of truth and intentionality, subjectivity and objectivity, of relevance to philosophy, the humanities and social sciences.