You are beginning the study of human nature. You can not study human nature from a book, you must study yourself and your neighbors. This book may help you to know what to look for and to understand what you find, but it can do little more than this. It is true, this text gives you many facts learned by psychologists, but you must verify the statements, or at least see their significance to you, or they will be of no worth to you. However, the facts considered here, properly understood and assimilated, ought to prove of great value to you. But perhaps of greater value will be the psychological frame of mind or attitude which you should acquire. The psychological