There is, too, an immense interior depth to our human personality. Only the surface of our inner self is lighted up and is brought into clear focal consciousness. There are, however, dim depths underlying every moment of consciousness and these subterranean deeps are all the time shaping or determining the ideas, emotions, and decisions which surge up into the illuminated apex of consciousness. This submerged life is in part, no doubt, the slow deposit of previous experiences, the gathered wisdom of the social group in which we are imbedded, the residual savings from unuttered hopes and wishes, aspirations and intentions, “All I could never be, All, men ignored in me.” But at times our interior deep seems to be more than a deposit of the past. Incursions from beyond our own margin seem to occur. Inrushes from a wider spiritual world seem to take place. Vitalizing, energizing, constructive forces come from somewhere into men, as though another universe impinged upon our finite spirits. We cannot _prove_ by these somewhat rare and unusual mystical openings that there is an actual spiritual environment surrounding our souls, but there are certainly experiences which are best explained on that hypothesis, and there is no good reason for drawing any impervious boundary around the margins of the spiritual self within us. All attempts to reduce man’s inner spiritual life to the play of molecular forces have fallen through. Correlation between mind and brain cortex there certainly is and spirit, as we know it, expresses itself under, or in relation to, certain physical conditions. But it is impossible to establish a complete parallelism between mind-functions and brain-functions. The psychical, that is to say spirit, seems immensely to outrun its organ and to use brain as a musician uses an instrument. The psychological studies of Henri Bergson in France and of Dr. William McDougall at Oxford make a very strong argument for the view that the higher forms of consciousness cannot be explained in terms of brain action and that there is no well-defined physical correlate to the highest and most central psychical processes. I shall follow in the main the positions of my old teacher, Dr. McDougall, as worked out in his _Body and Mind_.