249 



6 1 conceive, then, that we may consider Kepler's 

 character as containing the general features of the character 

 of a scientific discoverer, though some of the features are 

 exaggerated, and some too feebly marked. His spirit of 

 invention was undoubtedly very fertile and ready, and this 

 and his perseverance served to remedy his deficiency in 

 mathematical artifice and method. But the peculiar 

 physiognomy is given to his intellectual aspect by his 

 dwelling on those erroneous trains of thought which other 

 persons conceal from the world, and often themselves 

 forget, because they find means of stopping them at the 

 outset. In the beginning of his book, Argumenta Capitum, 

 he says, " If Christopher Columbus, if Magellan, if the 

 Portuguese, when they narrate their wanderings, are not 

 only excused, but if we do not wish these passages omitted, 

 and should lose much pleasure if they were, let no one 

 blame me for doing the same." Kepler's talents were a 

 kindly and fertile soil, which he cultivated with abundant 

 toil and vigour ; but with great scantiness of agricultural 

 skill and implements. Weeds and the grain throve side 

 by side almost undistinguished; and he gave a peculiar 

 appearance to his harvest, by gathering and preserving 

 the one class with as much care and diligence as the 

 other.' l 



' A typical example of the difference between ingenuity 

 and true genius is afforded by the contrast between Kepler 

 and Newton. Strongly impressed with the belief that 

 some " harmonic " relation must exist among the distances 

 of the several planets from the sun, and also among the 

 times of their revolution, Kepler passed a large part of his 

 early life in working out a series of guesses at this rela- 

 tion; some of which now strike us as not merely most 



1 Whewell, History of tlie Inductive Sciences, vol. i. 3rd ed., p. 320. 



