ABSTRACTION. 459 



proceed by fresh comparisons to a different general conception. Some- 

 times, again, we find that tiie same conception will serve, by merely leaving 

 out some of its circumstances ; and by this higher effort of abstraction, we 

 obtain a still more general conception ; as in the case formerly referred to, 

 the scientific world rose from the conception of poles to the general concep- 

 tion of opposite properties in opposite directions; or as those South-Sea 

 islanders, whose conception of a quadruped had been abstracted from hogs 

 (the only animals of that description which they had seen), when they after- 

 ward compared that conception with other quadrupeds, dropped some of 

 the circumstances, and arrived at the more general conception which Eu- 

 ropeans associate with the term. 



These brief remarks contain, I believe, all that is well grounded in the 

 doctrine, that the conception by which the mind .arranges and gives unity 

 to phenomena must be furnished by the mind itself, and that we find the 

 right conception by a tentative process, trying first one and then another 

 until we hit the mark. The conception is not furnished by the mind until 

 it has been furnished to the mind; and the facts which supply it are some- 

 times extraneous facts, but more often the very facts which we are attempt- 

 ing to arrange by it. It is quite true, however, that in endeavoring to 

 arrange the facts, at whatever point we begin, we never advance three 

 steps without forming a general conception, more or less distinct and pre- 

 cise; and that this general conception becomes the clue which we instant- 

 ly endeavor to trace through the rest of the facts, or rather, becomes the 

 standard with wbiiih we thenceforth compare them. If we are not satis- 

 fied with the agreements which we discover among the phenomena by com- 

 paring them with this type, or with some still more general conception 

 which by an additional stage of abstraction we can form from the type; 

 we change our path, and look out for other agreements ; we recommence 

 the comparison from a different starting-point, and so generate a different 

 set of general conceptions. This is the tentative process which Dr. Whe- 

 well speaks of ; and which has not unnaturally suggested the theory, that 

 the conception is supplied by the mind itself; since the different concep- 

 tions which the mind successively tries, it either already possessed from 

 its previous experience, or they were supplied to it in the first stage of the 

 corresponding act of comparison ; so that, in the subsequent part of the 

 process, the conception manifested itself as something compared with the 

 phenomena, not evolved from them. 



§ 4. If this be a correct account of the instrumentality of general con- 

 ceptions in the comparison which necessarily precedes Induction, we are 

 now able to translate into our own language what Dr. Whewell means by 

 saying that conceptions, to be subservient to Induction, must be "clear" 

 and " appropriate." 



If the conception corresponds to a real agreement among the phenome- 

 na ; if the comparison which we have made of a set of objects has led us to 

 class them according to real resemblances and differences ; the conception 

 which does this can not fail to be appropriate, for some purpose or other. 

 The question of appropriateness is relative to the particular object we 

 have in view. As soon as, by our comparison, we have ascertained some 

 agreement, something which can be predicated in common of a number of 

 objects; we have obtained a basis on which an inductive process is capa- 

 ble of being founded. But the agreements, or the ulterior consequences 

 to which those agreements lead, may be of very different degrees of impor- 



