DEFINITIONS OF SCIENTIFIC GENIUS. 243 



sophy, were of the most brilliant and captivating character. 

 In discovering the nature of voltaic action, the essential 

 intellectual requisite was to have a distinct conception 

 of that which Faraday expressed by the remarkable phrase, 

 " An axis of power having equal and opposite forces" 

 And the distinctness of this idea in Faraday's mind shines 

 forth in every part of his writings.' 'He appears to 

 possess the idea of this kind of force with the same 

 eminent distinctness with which Archimedes in the ancient 

 and Stevinus in the modern history of science possessed 

 the idea of pressure, and were thus able to found the idea 

 of mechanics. And when he cannot obtain these distinct 

 modes of conception, he is dissatisfied, and conscious of 

 defect.' 1 



The mental faculties of great scientific discoverers, 

 though more penetrating, truthful, and accurate than 

 those of men in general, are limited by the same general 

 conditions. 'Many of those who have made very great 

 discoveries have laboured under the imperfection of 

 thought which was the obstacle to the next, step in know- 

 ledge. Though Kepler detected, with great acutenes?, 

 the numerical laws of the solar system, he laboured in 

 vain to conceive the very simplest of the laws of motion 

 by which the paths of the planets are governed. Though 

 Priestley made some important steps in chemistry, he 

 could not bring his mind to admit the doctrine of a 

 general principle of oxidation.' ' To err in this way is 

 the lot not only of men in general, but of men of great 

 endowments, and very sincere love of truth.' 2 



Buffon said that scientific genius ' is only protracted 

 patience.' Cuvier said : ' In the exact sciences at least, 

 it is the patience of a sound intellect, when invincible, 



1 Whewell, History of Inductive Sciences, vol. iii. Srded., p. 147. 



2 Whewell, Philosophy of the Inductive Sciences, vol. ii. p. 175. 



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