"La force et la foiblesse de l'esprit," said Rochefoucauld, "sont mal nommées; elles ne sont, en effect, que la bonne ou la mauvaise des organes du corps." Science wastes itself hunting in the other direction. We are flooded with evidences of the effects of the mind on the body, and so our attention is diverted from the enormously greater effects of the body on the mind. It is rather astonishing that the Wassermann reaction has not caused the latter to be investigated more thoroughly. The first result of the general employment of that great diagnostic device was the discovery that thousands of cases of so-called mental disease were really purely physical in origin--that thousands of patients long supposed to have been crazed by seeing ghosts, by love, by grief, or by reverses in the stock-market were actually victims of the small but extremely enterprising _spirochæte pallida._ The news heaved a bomb into psychiatry, but it has so far failed to provoke a study of the effects of other such physical agents. Even the effects of this one agent remain to be inquired into at length. One now knows that it may cause insanity, but what of the lesser mental aberrations that it produces? Some of these aberrations may be actually beneficial. That is to say, the mild toxemia accompanying the less virulent forms of infection may stimulate the brain to its highest functioning, and so give birth to what is called genius--a state of mind long recognized, by popular empiricism, as a sort of half-way station on the road to insanity. Beethoven, Nietzsche and Schopenhauer suffered from such mild toxemias, and there is not the slightest doubt that their extraordinary mental activity was at least partly due to the fact. That tuberculosis, in its early stages, is capable of the same stimulation is a commonplace of observation. The consumptive may be weak physically, but he is usually very alert mentally. The history of the arts, in fact, shows the names of hundreds of inspired consumptives.