tural man, that we all produce such substitutive formations, and that only the amount, intensity, and distribution of these substitutive formations justify the practical conception of illness and the conclusion of constitutional inferiority. Following the slight signs in Leonardo's personality we would place him near that neurotic type which we designate as the "compulsive type," and we would compare his investigation with the "reasoning mania" of neurotics, and his inhibitions with the so-called "abulias" of the latter.
The object of our work was to explain the inhibitions in Leonardo's sexual life and in his artistic activity. For this purpose we shall now sum up what we could discover concerning the course of his psychic development.
We were unable to gain any knowledge about his hereditary factors, on the other hand we recognize that the accidental circumstances of his childhood produced a far reaching disturbing effect. His illegitimate birth deprived him of the influence of a father until perhaps his fifth year, and left him to the tender seduction of a mother whose only consolation he was.
