This peculiarity will serve to indicate that in a large proportion of cases the parentage of genius is not entirely sound and normal. We must dismiss absolutely the notion that the parents of persons of genius tend to exhibit traits of a grossly insane or nervously degenerate character. The evidence for such a view is confined to a minute proportion of cases, and even then is usually doubtful. But it is another matter to assume that the parentage of genius is absolutely normal, and still less can we assert that genius always springs from entirely sound stocks. The statement is sometimes made that all families contain an insane element. That statement cannot be accepted. There are many people, including people of a high degree of ability, who can trace no gross mental or nervous disease in their families, unless remote branches are taken into account. Not many statistics bearing on this point are yet available. But Jenny Roller, in a very thorough investigation, found at Zurich in 1895 that "healthy" people had in 28 per cent. cases directly, and in 59 per cent. cases indirectly and altogether, a neuropathic heredity, while Otto Diem in 1905 found that the corresponding percentages were still higher--33 and 69. It should not, therefore, be matter for surprise if careful investigation revealed a traceable neuropathic element at least as frequent as this in the families which produce a man of genius. It may further, I believe, be argued that the presence of a neuropathic element of this kind in the ancestry of genius is frequently not without a real significance. Aristotle said in his _Poetics_ that poetry demanded a man with "a touch of madness," though the ancients, who frequently made a similar statement to this, had not our modern ideas of neuropathic heredity in their minds, but merely meant that inspiration simulated insanity. Yet "a touch of madness," a slight morbid strain, usually neurotic or gouty, in a preponderantly robust and energetic stock, seems to be often of some significance in the evolution of genius; it appears to act, one is inclined to think, as a kind of ferment, leading to a process out of all relation to its own magnitude. In the sphere of literary genius, Milton, Flaubert, and William Morris may help to illustrate this precious fermentative influence of a minor morbid element in vitally powerful stocks. Without some such ferment as this the energy of the stock, one may well suppose, might have been confined within normal limits; the rare and exquisite flower of genius, we know, required an abnormal stimulation; only in this sense is there any truth at all in Lombroso's statement that the pearl of genius develops around a germ of disease. But this is the utmost length to which the facts allow us to go in assuming the presence of a morbid element as a frequent constituent of genius. Even then we only have one of the factors of genius, to which, moreover, undue importance cannot be attached when we remember how often this