GENIUS AND MENTAL DISEASE. 663 



geologist as Mr. Haast has been at fault in regard to the antiquity of 

 the moa, may not other able geologists, who have supposed that the 

 mammoth, the cave-bear, and other extinct animals — the contempora- 

 ries of the Cro-Magnon artists who depicted them with such life-like 

 exactness — died out at a period long prior to the historic era, be 

 equally mistaken ? There seems no more reason for doubting that 

 the last surviving Elephas primigenius may have been killed by some 

 bold hunters of the Cro-Magnon race, in the time of one of the early 

 Pharaohs, than there is for questioning the fact that the last Dinornis 

 was killed by the Maori hunters in the reign of George III. 



GENIUS AND MENTAL DISEASE. 



By WILLIAM G. STEVENSON, M. D. 



IT were comparatively an easy task to explain psychological phe- 

 nomena by asserting, as did the metaphysicians of the past, and 

 as some do even at the present, that the human brain — the physical 

 sanctuary of thought — is merely an instrument through which various 

 spiritual beings operate, producing at one time the prophetic utter- 

 ances of the seer, at another time the gifted words of genius, and yet 

 again the extravagant and discordant expressions of madness. This was 

 the " working hypothesis " of Pagan antiquity in its efforts to explain 

 the utterances of its oracles, and also of the Christian fathers in their 

 attempts to explain the inspiration of the prophets and of the apostles. 



Greek supernaturalism and the Christian doctrine of inspiration 

 here found a common point of agreement, for both implied a " divine 

 intoxication " — an " overflowing of the mind " — because of its entire 

 possession by a divine influence, which, according as it was good or 

 evil, excited a " poetic furor " indicative of genius, or caused a wild 

 frenzy which was known as madness. 



Genius, therefore, was simply a reflection, through the human 

 brain, of an outside divinity of good ; while insanity was merely an 

 expression of satanic possession — an inspiration of an evil spirit — and 

 in nature was closely allied to genius. 



This belief, although somewhat modified by filtering through ages 

 of changing thought, has been superseded only in very recent times 

 by the conceptions which reflect the broader generalizations of in- 

 ductive science. From the data thus furnished comes the conviction 

 that mental phenomena "are dependent upon the properties and 

 molecular activities of nerve-tissue," and that there is a "bond of 

 union " between psychical expressions and a nervous mechanism, 

 although the nature of this union is unknown. The facts of con- 

 sciousness are marshaled before us with all the force of attested 

 verities, but are yet veiled with all the mystery of a passing dream. 



