330 INDUCTION. 



the mind, in framing the descriptions, adds something of its 

 own which it does not find in the facts. 



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 circum 

 ference 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. 



Having stated this fundamental difference between my 

 opinion and that of Dr. 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 consists 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 &quot; con 

 ception &quot; of an ellipse, he tried nineteen other imaginary paths, 

 which, finding them inconsistent with the observations, he was 

 obliged to reject. But as Dr. Whewell truly says, the suc 

 cessful hypothesis, though a guess, ought generally to be 

 called, not a lucky, but a skilful guess. The guesses which 

 serve to give mental unity and wholeness to a chaos of 

 scattered particulars, are accidents which rarely occur to any 

 minds bat those abounding in knowledge and disciplined in 

 intellectual combinations- 

 How far this tentative method, so indispensable as a means 

 to the colligation of facts for purposes of description, admits 

 of application to Induction itself, and what functions belong 

 to it in that department, will be considered in the chapter of 

 the present Book which relates to Hypotheses. On the pre- 



