With your permission I will commence my exposition of the very serious and important subject that is the theme of my lecture to-day with the recital of a little story which will lead us straightway into the revolutionising events of this war. A Hungarian, who had the opportunity of observing at close quarters a part of the revolutionary upheaval in Russia, told me that the new revolutionary rulers of a Russian town found with consternation that the change from the old to the new regime had not taken place as rapidly as it should have done according to their doctrinal calculations. According to the teachings of the materialistic idea of history they could have set up the new social order immediately after they had got the entire power into their hands. Instead of this, irresponsible elements, which were antagonistic to any new order of things, obtained the upper hand, so that the power gradually slipped from the hands of the originators of the revolution. Then the leaders of the movement put their heads together in order to find out what had gone wrong in their calculations. Finally they agreed that perhaps the materialistic idea was after all too one-sided, as it only took into consideration the economic and commercial relations, and had forgotten to take into account one small matter, the feelings and thoughts of man, in a word, the psyche. They were sufficiently consistent to send emissaries immediately to German speaking countries, in order to obtain psychological works, so that they might get at least subsequently some knowledge of this neglected science. Many thousands of human lives fell victims, perhaps to no purpose, to this omission of the revolutionaries; the failure of their efforts resulted in their making one discovery however, namely, that of the mind. A somewhat similar thing has occurred among neurologists during the war. The war has produced an enormous number of nervous disorders which call for elucidation and cure; however, the familiar organic-mechanistic explanation hitherto adopted—which in some way corresponds to the materialistic idea of history in sociology—completely failed. The mass-experiment of the war has produced various severe neuroses, including those in which there could be no question of a mechanical influence, and the neurologists have likewise been forced to recognise that something was missing in their calculations, and this something was again—the psyche.