INDUCTIONS IMPROPERLY SO CALLED. 363 



Yet it is a fact, surely, that the planet does 

 describe an ellipse ; and a fact which we could see, if 

 we had adequate visual organs and a suitable position. 

 Not having these advantages, but possessing the 

 conception of an ellipse, or (to express the meaning 

 in less technical language) knowing what an ellipse 

 was, Kepler tried whether the observed places of the 

 planet were consistent with such a path. He found 

 they were so; and he, consequently, asserted as a fact 

 that the planet moved in an ellipse. But this fact, 

 which Kepler did not add to, but found in, the 

 motions of the planet, namely, that it occupied in 

 succession the various points in the circumference of 

 a given ellipse, was the very fact, the separate parts 

 of which had been separately observed; it was the 

 sum of the different observations. It superadded 

 nothing to the particular facts which it served to bind 

 together : except, indeed, the knowledge that a resem- 

 blance existed between the planetary orbit and other 

 ellipses ; an accession the nature and amount of 

 which will be fully considered hereafter*. 



Having stated this fundamental difference between 

 my views and those of Mr. Whewell, I must add, that 

 his account of the manner in which a conception is 

 selected, suitable to express the facts, appears to me 

 perfectly just. The experience of all thinkers will, I 

 believe, testify that the process is tentative; that it con- 

 sists of a succession of guesses ; many being rejected, 

 until one at last occurs fit to be chosen. We know 

 from Kepler himself that before hitting upon the "con- 

 ception "of an ellipse, he tried nineteen other imagi- 

 nary paths, which, finding them inconsistent with the 

 observations, he was obliged to reject. But as Mr. 



* Vide infra, book iv., ch. 1. 



