A far-reaching discussion of human psychology and traditional methods of investigation. The author, a professor of psychology at Harvard, is known for his research on child development (The Growth of the Child, 1978; The Second Year, 1981). These studies are reflected in this book, for instance in a discussion of inhibited and uninhibited children, but the main concern here is with such profound problems as the meaning of human consciousness and the relation between our sense (or illusion) of having free will, and the forces of a biological determinism of which we are largely unaware. Inevitably involved with this dilemma of will and destiny, argues Kagan, is the question of method. If human consciousness gives an inherently incomplete picture of reality, then conscious methods of scientific investigation are limited to precisely the same extent. The discussion is carried on with masterful control of a vast past and present scientific and philosophical literature, together with its moral and political contexts and implications. One of the most arresting chapters here deals with "Creativity in Science," where Kagan tries to understand how it is that people like Einstein, Mendel, and Pavlov came to make their miraculous discoveries. In conclusion, two fictional characters, Simpliciter and Reflectiva, engage in a witty dialogue about the concept of self-consciousness. Highly stimulating and rewarding work for readers willing to grapple with hard concepts, detailed discussions, and a sweeping range of allusions.