“I had been enabled to discover in genius various characters of degeneration which are the foundation and the sign of nearly all forms of congenital mental abnormality, but the exaggerated extension which was at that time given to theories of degeneration, and still more the vague and inexact character of that conception, had repelled me; so that I accepted the facts, but not their ultimate consequences. How, in fact, can one suppress a feeling of horror at the thought of associating with idiots and criminals those individuals who represent the highest manifestations of the human spirit?

“But recent teratologic researches, especially those of Gegenbauer, have shown that the phenomena of atavistic retrogression do not always indicate true degradation, but that very often they are simply a compensation for considerable development and progress accomplished in other directions. Reptiles have more ribs than we have; quadrupeds and apes possess more muscles than we do, and an entire organ, the tail, which we lack. It has been in losing these advantages that we have gained our intellectual superiority. When this is seen, the repugnance to the theory of genius as degeneration at once disappears. Just as giants pay a heavy ransom for their stature in sterility and relative muscular and mental weakness, so the giants of thought expiate their intellectual force in degeneration and psychoses. It is thus that the signs of degeneration are found more frequently in men of genius than even in the insane.”