Two great developments have taken place in medicine which bring it into much closer relations with education than was formerly the ease. One of these is the greatly increased attention to hygiene, to prevention rather than cure, to use the words of the old adage; while the other great development, one especially active at the moment, is the application to disorders of the mind of principles similar to those which have long been applied to disorders of the body. It is recognised that the process of psychotherapy by which mental disorder is remedied is one in which the therapeutic process is of essentially the same kind as that by which the individual is normally adapted to social life. In the early stages of psychological medicine the chief stress was laid on suggestion, of which hypnotism was the most striking form.