Psychological knowledge, according to the same authority,[58:1] is gradually leaking into the world of medicine. The power of suggestion, with its varied methods, is slowly becoming a most important therapeutic agent in the hands of reputable practitioners. The time has arrived when medical students, about to enter upon professional life, should be equipped with a knowledge of scientific psychology. Physicians do not now deserve sympathy, if they are dumfounded when quacks and pretenders are successful where their own attempts at curing have failed. It is evident, however, that reform in this field is at hand, and it may be admitted that even those knights-errant have helped, after many centuries, to direct the public interest to the paramount importance of psychology in medicine. We may cite the invocations of the Egyptian priests to obtain a cure from each god for those submitted to his influence; the magic formulas, which taught the use of herbs against disease; the medicine of Esculapius's descendants, the Asclepiads, an order of Greek physicians, who practised medicine under the reputed inspiration of that deity, and were bound by oath not to reveal the secrets of their art. Is it necessary to speak of the king's touch, of the miraculous cures at the tomb of the French ascetic priest, François Paris (1690-1727), and especially of Lourdes, and other noted pilgrimage resorts? Many professional healers may be mentioned, "of whom some were honest and believed themselves to be endowed with supernatural powers like certain magnetisers, and who used suggestion without knowing it, as for example the Irishman Greatrakes (1628-1700), the German priest Gassner (1727-1779), and many others whose fame does not extend beyond the region where they exercised their mysterious power."[59:1] In the same category, as regards their _modus operandi_, may be classed medical charms and healing-spells. These serve also to inspire hope, or the expectation of cure, in the patient's mind, and thus act as tonics; they may also be useful as a means of diverting the mind of a hypochondriac, and changing the current of his thoughts, in which sense they may be classed as mental alteratives.