It has always seemed to me a particular duty of the psychologist from time to time to leave his laboratory and with his little contribution to serve the outside interests of the community. Our practical life is filled with psychological problems which have to be solved somehow, and if everything is left to commonsense and to unscientific fancies about the mind, confusion must result, and the psychologist who stands aloof will be to blame. Hence I tried in my little book “On the Witness Stand” to discuss for those interested in law the value of exact psychology for the problems of the courtroom. In “Psychotherapy” I showed the bearing of a scientific study of the mind on medicine. In “Psychology and the Teacher” I outlined its consequences for educational problems. In “Psychology and Industrial Efficiency” I studied the importance of exact psychology for commerce and industry.
