CHAPTER IWHAT IS PSYCHOLOGY? Wise men study the sciences which deal with the origins and development of animal life, with the structure of the cells, with the effect of various diseases upon the tissues and fluids of the body; they study the causes of the reactions of the body cells to disease germs, and search for the origin and means of extermination of these enemies to health. They study the laws of physical well-being. They seek for the... more...