GROUND OF INDUCTION. 223 



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. 



OF THE GROUND OF INDUCTION. 



§ 1. Induction properly so called, as distinguished from those mental 

 operations, sometimes, though improperly, designated by the name, which I 

 have attempted in the pi*eceding chapter to characterize, may, then, be sum- 

 marily defined as Generalization from Experience. £*It consists in inferring 

 from some individual instances in which a phenomenon is observed to oc- 

 cur, that it occurs in all instances of a certain class ; namely, in all which 

 resemble the former, in what are regarded as the material circumstances!^ 



In what way the material circumstances are to be distinguished fi*Slrn 

 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 ob- 

 serve, that\there is a principle implied in the very statement of what Induc- 

 tion is ; an assumption with regard to the course of nature and the order 

 of the universe ; namely, that there are such things in nature as parallel 

 case8?)that what happens once, will, under a sufficient degree of similarity 

 of circumstances, happen again, and not only again, but as often as the 

 same circumstances recur. This, I say, is an assumption, involved in every 

 case of induction. And, if we consult the actual course of nature, we find 

 that the assumption is warranted. The universe, so far as known to us, is 

 so constituted, that whatever is true in any one case, is true in all cases of 

 a certain description ; the only difficulty is, to find what description. 



This universal fact, which is our warrant for all inferences from experi- 

 ence, has been described by different philosophers in different forms of lan- 

 guage : that the course of nature is uniform ; that the universe is governed 

 by general laws ; and the like. One of the most usual of these modes of 

 expression, but also one of the most inadequate, is that which has been 

 brought into familiar use by the metaphysicians of the school of Reid 

 and Stewart. The disposition of the human mind to generalize from ex- 

 perience — a propensity considered by these philosojjhers as an instinct of 

 our nature — they usually describe under some such name as " our intuitive 

 conviction that the future will resemble the past." Now it has been well 

 pointed out by Mr. Bailey,* that (whether the tendency be or not an orig- 

 inal and ultimate element of our nature). Time, in its modifications of past, 

 present, and future, has no concern either with the belief itself, or with the 

 grounds of it. We believe that fire will burn to-morrow, because it burned 

 to-day and yesterday; but we believe, on precisely the same grounds, that 

 it burned before we were born, and that it burns this very day in Cochin- 

 China. It is not from the past to the future, as past and future, that we 



* Essays on the Pursuit of Truth. 



I 



