INDUCTIVE EPOCH OF NEWTON. 417 



mastered geometry. This fondness for handicraft employments, and 

 for making models and machines, appears to be a common prelude of 

 excellence in physical science ; 24 probably on this very account, that it 

 arises from the distinctness of intuitive power with which the child 

 conceives the shapes and the working of such, material combinations. 

 Newton's inventive power appears in the number and variety of the 

 mathematical artifices and combinations which he devised, and of 

 which his books are full. If we conceive the operation of the invent- 

 ive faculty in the only way in which it appears possible to conceive it ; 

 that while some hidden source supplies a rapid stream of possible 

 suggestions, the mind is on the watch to seize and detain any one of 

 these which will suit the case in hand, allowing the rest to pass by and 

 be forgotten ; we shall see what extraordinary fertility of mind is 

 implied by so many successful efforts ; what an innumerable host of 

 thoughts must have been produced, to supply so many that deserved 

 to be selected. And since the selection is performed by tracing the 

 consequences of each suggestion, so as to compare them with the requi- 

 site conditions, we see also what rapidity and certainty, in drawing 

 conclusions the mind must possess as a talent, and what watchfulness 

 and patience as a habit. 



The hidden fountain of our unbidden thoughts is for us a mystery ; 

 and we have, in our consciousness, no standard by which we can meas- 

 ure our own talents ; but our acts' and habits are something of which 

 we are conscious ; and we can understand, therefore, how it was that 

 Newton could not admit that there was any difference between himself 

 and other men, except in his possession of such habits as we have men- 

 tioned, perseverance and vigilance. When he was asked how he made 

 his discoveries, he answered, "by always thinking about them ;" and 

 at another time he declared that if he had done any thing, it was due 

 to nothing but industry and patient thought : " I keep the subject of 

 my inquiry constantly before me, and wait till the first dawning opens 

 gradually, by little and little, into a full and clear light." No better 

 account can be given of the nature of the mental effort which gives to 

 the philosopher the full benefit of his powers ; but the natural powers 

 of men's minds are not on that account the less different. There are 

 many who might wait through ages of darkness without being visited 

 by any dawn. 



The habit to which Newton thus, in some sense, owed his discover* 



24 As in Galileo, Hooke, Huyghens, and others. 

 VOL. I. 27 



