ABSTRACTION. 



429 



precise ; and that this general con- 

 ception becomes the chie which we 

 instantly endeavour to trace through 

 the rest of the facts, or rather, be- 

 comes the standard with which we 

 thenceforth compare them. If we 

 are not satisfied with the agreements 

 which we discover among the pheno- 

 mena by comparing them with this 

 type, or with some still more gene- 

 ral 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 gene- 

 rate a different set of general concep- 

 tions. This is the tentative process 

 which Dr. Whewell speaks of, and 

 which has not unnaturally suggested 

 the theory that the conception is sup- 

 plied by the mind itself, since the 

 different conceptions which the mind 

 successively tries, it either already 

 possessed from its previous experi- 

 ence, 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 some- 

 thing 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 pheno- 

 mena ; 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 cannot 

 fail to be appropriate, for some pur- 

 pose or other. The question of appro- 

 priateness is relative to the particular 

 object we have in view. As soon as, 

 by ovu- comparison, we have ascer* 



tained some agreement, something 

 which can be predicated in common 

 of a number of objects, we have ob- 

 tained a basis on which an inductive 

 process is capable of being founded. 

 But the agreements, or the ulterior 

 consequences to which those agree- 

 ments lead, may be of very different 

 degrees of importance. If, for in- 

 stance, we only compare animals ac- 

 cording to their colour, and class those 

 together which are coloured alike, we 

 form the general conceptions of a 

 white animal, a black animal, &c., 

 which are conceptions legitimately 

 formed ; and if an induction were to 

 be attempted concerning the causes 

 of the colours of animals, this com- 

 parison would be the proper and 

 necessary preparation for such an 

 induction, but would not help us 

 towards a knowledge of the laws of 

 any other of the properties of animals ; 

 while if, with Cuvier, we compare and 

 class them according to the structure 

 of the skeleton, or, with Blainville, 

 according to the nature of their out- 

 ward integuments, the agreements 

 and differences which are observable 

 in these respects are not only of much 

 greater importance in themselves, but 

 are marks of agreements and differ- 

 ences in many other important parti- 

 culars of the structure and mode of 

 life of the animals. If, therefore, the 

 study of their structure and habits be 

 our object, the conceptions generated 

 by these last comparisons are far more 

 " appropriate " than those generated 

 by the former. Nothing, other than 

 this, can be meant by the appropriate- 

 ness of a conception. 



When Dr. Whewell says that the 

 ancients, or the schoolmen, or any 

 modern inquirers, missed discovering 

 the real law of a phenomenon because 

 they applied it to an inappropriate 

 instead of an appropriate conception, 

 he can only mean that in comparing 

 various instances of the phenomenon, 

 to ascertain in what those instances 

 agreed, they missed the important 

 points of agreement, and fastened 

 upon such as were either ima^nary, 



