In a word, it is plain at once that, given the necessarily limited number of ways in which the psycho-physical organism reacts under mental stimulations, certain neural phenomena may, in any two cases, be, in themselves, perfectly similar, although their respective mental causes or occasions may be as different, each from the other, as the Moonlight Sonata of Beethoven, or the working out of the Law of Gravitation by Newton, or the elaboration of the implications of the Categorical Imperative by Kant, are different from the sudden jumping of a live mouse in the face of an hysterically-disposed young woman, or as the various causes of tears and laughter throughout the whole world. IV. FIRST PERIOD OF CATHERINE’S LIFE, 1447 TO 1477, IN ITS THREE STAGES. If we next go back to the first period of her life, in its three stages of the sixteen years of her girlhood, 1447-1463, the first ten years of her married life, 1463-1473, and the four years of her Conversion and active Penitence, 1473-1477, we shall find, I think, in the matter of temperament and psycho-physical conditions, little or nothing but a rare degree of spiritual sensitiveness, and an extraordinary close-knittedness of body and mind. 1. _From her childhood to her conversion._ Thus, already in her early childhood, that picture of the Pietà seems to have suggested religious ideas and feelings with the suddenness and emotional solidity of a physical seizure--an impression still undimmed when she herself recounted it, some fifty years later, to her two intimates.--It is true that during those first, deeply unhappy ten years of marriage, we cannot readily find more than indications of a most profound and brooding melancholy, the apparent result of but two factors,--a naturally sad disposition and acutely painful domestic circumstances. Yet it is clear, from the sequel, that more and other things lay behind. It is indeed evident that she possessed a congenitally melancholy temperament; that nothing but the rarest combination of conditions could have brought out, into something like elastic play and varied exercise, her great but few and naturally excessive qualities of mind and heart; that these conditions were not only absent, but were replaced by circumstances of the most painful kind; and that she will hardly, at this time, have had even a moment’s clear consciousness of any other sources than just those conditions for her deep, keen, and ever-increasing dissatisfaction with all things, her own self included: all peace and joy, the very capacity for either seemed gone, and gone for ever. But it is only the third stage, with its sudden-seeming conversion on March 20, 1473, and the then following four years of strenuously active self-immolation and dedication to the humblest service of others, which lets us see deep into those previous years of sullen gloom and apparently hopeless drift and dreary wastage.