The enquiry made possible by Freud’s work has already resulted fruitfully; we are indebted to this stimulation for some bold attacks upon the territory of the history of the human mind. There are the works of Riklin,[5] Abraham,[6] Rank,[7] Maeder,[8] Jones,[9]—recently Silberer has joined their ranks with a beautiful investigation entitled “Phantasie und Mythus.”[10] We are indebted to Pfister[11] for a comprehensive work which cannot be overlooked here, and which is of much importance for Christian religious psychology. The leading purpose of these works is the unlocking of historical problems through the application of psychoanalytic knowledge; that is to say, knowledge drawn from the activity of the modern unconscious mind concerning specific historical material. I must refer the reader entirely to the specified works, in order that he may gain information concerning the extent and the kind of insight which has already been obtained. The explanations are in many cases dubious in particulars; nevertheless, this detracts in no way from the total result. It would be significant enough if only the far-reaching analogy between the psychologic structure of the historical relics and the structure of the recent individual psychologic products alone were demonstrated. This proof is possible of attainment for every intelligent person through the work done up to this time. The analogy prevails especially in symbolism, as Riklin, Rank, Maeder, and Abraham have pointed out with illuminating examples; it is also shown in the individual mechanisms of unconscious work, that is to say in repression, condensation, etc., as Abraham explicitly shows. Up to the present time the psychoanalytic investigator has turned his interest chiefly to the analysis of the individual psychologic problems. It seems to me, however, that in the present state of affairs there is a more or less imperative demand for the psychoanalyst to broaden the analysis of the individual problems by a comparative study of historical material relating to them, just as Freud has already done in a masterly manner in his book on “Leonardo da Vinci.”[12] For, just as the psychoanalytic conceptions promote understanding of the historic psychologic creations, so reversedly historical materials can shed new light upon individual psychologic problems. These and similar considerations have caused me to turn my attention somewhat more to the historical, in the hope that, out of this, new insight into the foundations of individual psychology might be won. CHAPTER I CONCERNING THE TWO KINDS OF THINKING