Page:Popular Science Monthly Volume 27.djvu/470

452 Still, it may be said, this is, after all, only unscientific opinion. Has Science, with her more careful method of investigating and proving, anything to say on this interesting theme? It is hardly to he supposed that she would have overlooked so fascinating a subject. And, as a matter of fact, it has received a considerable amount of attention from pathologists and psychologists. And here for once Science appears to support the popular opinion. The writers who have made the subject their special study agree as to the central fact that there is a relation between high intellectual endowment and mental derangement, though they differ in their way of defining this relation. This conclusion is reached both inductively by a survey of facts, and deductively by reasoning from the known nature and conditions of great intellectual achievement on the one hand, and of mental disease on the other.

What we require first of all is clearly as many instances as can be found of men of genius who have exhibited intellectual or moral peculiarities which are distinctly symptomatic of mental disease. Such a collection of facts, if sufficient, will supply us with a basis for induction. In making this collection we need not adopt any theory respecting the nature either of genius or of mental disease. It is sufficient to ay that we include under the former term all varieties of originative power, whether in art, science, or practical affairs. And as to the latter term, it is enough to start with the assumption that fully developed insanity is recognizable by certain well-known marks; and that there are degrees of mental deterioration, and a gradual transition from mental health to mental disease, the stages of which also can, roughly at least, be marked off and identified.

In surveying the facts which have been relied on by writers, we shall lay most stress on mental as distinguished from bodily or nervous symptoms. And of these we may conveniently begin with the less serious manifestations:

1. The lowest grade of mental disturbance is seen in that temporary appearance of irrationality which comes from an extreme state of "abstraction" or absence of mind. To the vulgar, as already hinted, all intense preoccupation with ideas, by calling off the attention from outer things and giving a dream-like appearance to the mental state, is apt to appear symptomatic of "queerness" in the head. But in order that it may find a place among distinctly abnormal features this absence of mind must attain a certain depth and persistence. The ancient story of Archimedes, and the amusing anecdotes of Newton's