This little book by the author of Psychoanalysis in the Classroom is a vivid and often interesting account of some important aspects and functions of mind. It suffers from the inevitable defects which accompany the attempt to put complex and profound matters into a very small compass, into language which can be understood at first glance by readers who have no previous acquaintance with the subject. Mr. Green has brought out some useful points, with illustration and imagery which is always apt and interesting. 'Daydreaming' (Chapter IX), 'Fears' (Chapter XVII), 'The Place of Reason' (Chapter VI) are among the best chapters, and on most of the topics he has something suggestive and useful to say.