The book deals with the nature and evolution of the mind of man and is an attempt to delineate its intangible existence as a function and product of the flesh and blood of tangible brain tissue. In the process, the book necessarily delves into anatomy and function of brain and into philosophy. An intention was also to arrive at some definite ideas on philosophy. Hopefully, in the end, to elucidate the two conjoined aspects of the human mind, the tangible physical body of the real world, and the intangible conceptual world of ideas.