First Published in 1999. This is volume III of 10 from the international library of psychology, looking at physiological psychology and focuses on the neural basis of thought. The papers contained in this book may, from the point of view of empiricism, be regarded as an attempt to advance another step along the path of the Peirce-James-Bergson tradition. It aims at presenting the neurological aspect of a theory of knowledge which was published eleven years ago under the title Elements in Thought and Emotion.