334 INDUCTION. 



second law embi-aces a greater number of instances, covers as it were a 

 greater space of ground, than the first. 



Thus, in our former example, the law that the contact of an object 

 causes a change in the state of the nerve, is more general than the law 

 that contact with an object causes sensation, since, for aught we know, the 

 change in the nerve may equally take place when, from a counteracting 

 cause, as, for instance, strong mental excitement, the sensation does not 

 follow ; as in a battle, where wounds are sometimes received without any 

 consciousness of receiving them. And again, the law that change in the 

 state of a nerve produces sensation, is more general than the law that con- 

 tact with an object produces sensation ; since the sensation equally follows 

 the change in the nerve when not produced by contact with an object, but 

 by some other cause ; as in the well-known case, when a person who has 

 lost a limb feels the same sensation which he has been accustomed to call 

 a pain in the limb. 



Not only are the laws of more immediate sequence into which the law 

 of a remote sequence is resolved, laws of greater generality than that law 

 is, but (as a consequence of, or rather as implied in, their greater general- 

 ity) they are more to be relied on ; there are fewer chances of their being 

 ultimately found not to be universally true. From the moment when the 

 sequence of A and C is shown not to be immediate, but to depend on an 

 intervening phenomenon, then, however constant and invariable the se- 

 quence of A and C has hitherto been found, possibilities arise of its failure, 

 exceeding those which can effect either of the more immediate sequences, 

 A, B, and B, C. The tendency of A to produce C may be defeated by 

 whatever is capable of defeating either the tendency of A to produce B, 

 or the tendency of B to produce C ; it is, therefore, twice as liable to failure 

 as either of those more elementary tendencies ; and the generalization that 

 A is always followed by C, is twice as likely to be found erroneous. And 

 so of the converse generalization, that C is always preceded and caused by 

 A; which will be erroneous not only if there should happen to be a sec- 

 ond immediate mode of production of C itself, but moreover if there be 

 a second mode of production of B, the immediate antecedent of C in the 

 sequence. 



The resolution of the one generalization into Ihe other two, not only 

 shows that there are possible limitations of the former, from which its two 

 elements are exempt, but shows also where these are to be looked for. As 

 soon as we know that B intervenes between A and C, we also know that 

 if there be cases in which the sequence of A and C does not hold, these are 

 most likely to be found by studying the effects or the conditions of the 

 phenomenon B, 



It appears, then, that in the second of the three modes in which a law 

 may be resolved into other laws, the latter are more general, that is, extend 

 to more cases, and are also less likely to require limitation from subsequent 

 experience, than the law which they serve to explain. They are more near- 

 ly unconditional; they are defeated by fewer contingencies; they are a 

 nearer approach to the universal truth of nature. The same observations 

 are still more evidently true with regard to the first of the three modes of 

 resolution. When the law of an effect of combined forces is resolved into 

 the separate laws of the causes, the nature of the case implies that the law 

 of the effect is less general than the law of any of the causes, since it only 

 holds when they are combined; while the law of any one of the causes 

 holds good both then, and also when that cause acts apart from the rest. 



