COMPOSITION OF CAUSES. 271 



or not to that of the quantities of heat applied, can be established between 

 them. Thus the supposed axiom of the proportionality of effects to their 

 causes fails at the precise point where the principle of the Composition of 

 Causes also fails ; viz., where the concurrence of causes is such as to deter- 

 mine a change in the properties of the body generally, and render it sub- 

 ject to new laws, more or less dissimilar to those to which it conformed in 

 its previous state. The recognition, therefore, of any such law of propor- 

 tionality is superseded by the more comprehensive principle, in which as 

 much of it as is true is implicitly asserted.* 



The general remarks on causation, which seemed necessary as an intro- 

 duction to the theory of the inductive process, may here terminate. That 

 process is essentially an inquiry into cases of causation. All the uniformi- 

 ties which exist in the succession of phenomena, and most of the uniformi- 

 ties in their co-existence, are either, as we have seen, themselves laws of 

 causation, or consequences resulting from, and corollaries capable of being 

 deduced from, such laws. If we could determine what causes are correct- 

 ly assigned to what effects, and what effects to what causes, we should be 

 virtually acquainted with the whole course of nature. All those uniformi- 

 ties which are mere results of causation might then be explained and ac- 

 counted for ; and every individual fact or event might be predicted, pro- 

 vided we had the requisite data, that is, the requisite knowledge of the cir- 

 cumstances which, in the particular instance, preceded it. 



To ascertain, therefore, what are the laws of causation which exist in na- 

 ture ; to determine the effect of every cause, and the causes of all effects, 

 is the main business of Induction ; and to point out how this is done is the 

 chief object of Inductive Logic. 



* Professoi* Bain (Logic, ii., 39) points out a class of cases, other than that spoken of in 

 the text, which he thinks must be regarded as an exception to the Composition of Causes. 

 " Causes that merely make good the collocation for bringing a prime mover into action, or 

 that release a potential force, do not follow any such rule. One man may direct a gun upon 

 a fort as well as three : two sparks are not more eiFectual than one in exploding a barrel of 

 gunpowder. In medicine there is a certain dose that answers the end ; and adding to it does 

 no more good. " 



I am not sure that these cases are really exceptions. The law of Composition of Causes, I 

 think, is really fulfilled, and the appearance to the contrary is produced by attending to the 

 remote instead of the immediate effect of the causes. In the cases mentioned, the immedi- 

 ate effect of the causes in action is a collocation, and the duplication of the cause does double 

 the quantity of collocation. Two men could raise the gun to the required angle twice as 

 quickly as one, though one is enough. Two sparks put two sets of particles of the gunpow- 

 der into the state of intestine motion which makes them explode, though one is suflScient. It 

 is the collocation itself that does not, by being doubled, always double the effect ; because in 

 many cases a certain collocation, once obtained, is all that is required for the production of 

 the whole amount of effect which can be produced at all at the given time and place. Dou- 

 bling the collocation with difference of time and place, as by pointing two guns, or exploding 

 a second ban*el after the first, does double the effect. This remark applies still more to Mr. 

 Bain's third example, that of a double dose of medicine ; for a double dose of an aperient 

 does purge more violently, and a double dose of laudanum does produce longer and sounder 

 sleep. But a double purging, or a double amount of narcotism, may have remote effects dif- 

 ferent in kind from the effect of the smaller amount, reducing the case to that of heteropathic 

 laws, discussed in the text. 



