200 



INDTTCJTION. 



concerning which real Inductions have 

 already been made. Thus Kepler's 

 so-called law brought the orbit of Mars 

 into the class ellipse, and by doing so, 

 proved all the properties of an ellipse 

 to be true of the orbit : but in this 

 proof Kepler's law supplied the minor 

 premise, and not (as is the case with 

 real Inductions) the major. 



Dr. Whewell calls nothing Induc- 

 tion where there is not a new mental 

 conception introduced, and everything 

 induction where there is. But this 

 is to confound two very different 

 things, Invention and Proof. The 

 introduction of a new conception be- 

 longs to Invention : and invention 

 may be required in any operation, but 

 is the essence of none. A new concep- 

 tion may be introduced for descriptive 

 purposes, and so it may for inductive 

 purposes. But it is so far from con- 

 stituting induction, that induction 

 does not necessarily stand in need of 

 it. Most inductions require no con- 

 ception but what was present in every 

 one of the particular instances on 

 which the induction is grounded. 

 That all men are mortal is surely an 

 inductive conclusion ; yet no new 

 conception is introduced by it. Who- 

 ever knows that any man has died, 

 has all the conceptions involved in 

 the inductive generalisation. But 

 Dr. Whewell considers the process of 

 invention, which consists in framing 

 a new conception consistent with the 

 facts, to be not merely a necessary 

 part of all induction, but the whole 

 of it. 



The mental operation which ex- 

 tracts from a number of detached ob- 

 servations certain general characters 

 in which the observed phenomena re- 

 semble one another, or resemble other 

 known facts, is what Bacon, Locke, 

 and most subsequent metaphysicians, 

 have understood by the word Abstrac- 

 tion, A general expression obtained 

 by abstraction, connecting known facts 

 by means of common characters, but 

 without concluding from them to 

 unknown, may, I think, with strict 

 logical correctness, be termed a De- 



scription ; nor do I know in what othef 

 way things can ever be described. 

 My position, however, does not depend 

 on the employment of that particular 

 word : I am quite content to use Dr, 

 Whewell's term Colligation, or the 

 more general phrases, "mode of re- 

 presenting, or of expressing, pheno- 

 mena ; " provided it be clearly seen 

 that the process is not Induction, but 

 something radically different. 



What more may usefully be said on 

 the subject of Colligation, or of the 

 correlative expression invented by 

 Dr. Whewell, the Explication of Con- 

 ceptions, and generally on the subject 

 of ideas and mental representations 

 as connected with the study of facts, 

 will find a more appropriate place in 

 the Fourth Book, on the Operations 

 Subsidiary to Induction : to which I 

 must refer the reader for the removal 

 of any difficulty which the present 

 discussion may have left 



CHAPTER III. 



OP THE GROUND OP INDUCTION. 



§ I. Induction, properly so called, 

 as distinguished from those mental 

 operations, sometimes though impro- 

 perly designated by the name, which 

 I have attempted in the preceding 

 chapter to characterise, may, then, be 

 summarily defined as Generalisation 

 from Experience. It consists in infer- 

 ring from some individual instances 

 in which a phenomenon is observed to 

 occur, that it occurs in all instances of 

 a certain class ; namely, in all which 

 resemlle the former, in what are re- 

 garded as the material circumstances. 



In what way the material circum- 

 stances are to be distinguished from 

 those which are immaterial, or why 

 some of the circumstances are material 

 and others not so, we are not yet 

 ready to point out. We must first 

 observe that there is a principle im- 

 plied in the very statement of what 

 Induction is ; an assumption with re- 

 gard to the coiirse of nature and the 



