ment, an essential constituent in the man's genius. The mistake usually made is to exaggerate the insane character of such a fermentative element, and at the same time to ignore the element of sane and robust vigor which is equally essential to any high degree of genius. We may perhaps accept the ancient dictum of Aristotle as reported by Seneca: 'No great genius without some mixture of insanity.' But we have to remember that the 'insanity' is not more than a mixture, and it must be a finely tempered mixture.
This conclusion, suggested by our survey of British persons of preeminent intellectual aptitude, is thus by no means either novel or modern. It is that of most cautious and sagacious inquirers. The same position was, rather vaguely, adopted by Moreau (de Tours) in his Psychologie morbide dans ses rapports, etc., published in 1859, though, as his book was prolix and badly written, his proposition has often been misunderstood. He regarded genius as a 'neurosis,' but he looked upon such 'névrose' as simply "the synonym of exaltation (I do not say trouble or perturbation) of the intellectual faculties, . . . The word 'neurosis' would indicate a particular disposition of the faculties, a disposition still in part physiological, but overflowing these physiological limits"; and he presents a genealogical tree with genius, insanity, crime, etc., among its branches; the common root being 'the hereditary idiosyncratic nervous state.' J. Grasset, again, more recently (La superiorité intellectuelle et la névrose, 1900), while not regarding genius as a neurosis, considers that it is united to the neuroses by a common trunk, this trunk being a temperament and not a disease. The slight admixture of morbidity penetrating an otherwise healthy constitution, such as the present investigation suggests as of frequent occurrence in genius, results in an organization marked by what Moreau calls a 'neurosis' and Grasset a 'temperament.'
It has been necessary to state, as clearly as may be possible, the conclusions suggested by the present study as regards the pathological relationships of genius, because, although those conclusions are not essentially novel, the question is one that is apt to call out extravagant answers in one direction or another. The most fruitful part of our investigation seems, however, to lie not in the aid it may give towards the exact definition of genius—for which our knowledge is not sufficient—but in the promising fields it seems to open out for the analysis of genius along definite and precise lines. The time has gone by for the vague and general discussion of genius. We are likely to learn much more about its causation and nature by following out a number of detailed lines of inquiry on a carefully objective basis. Such an inquiry, as we have seen, is difficult on account of the defective nature of the material and the lack of adequate normal standards of comparison. Yet even with these limita-
