EXPLANATION OF LAWS. 519 



which tends to produce an accelerating motion towards the sun ; 

 the real motion being a compound of the two. 



It is necessary here to remark, that in this resolution of the 

 law of a complex effect, the laws of which it is compounded 

 are not the only elements. It is resolved into the laws of the 

 separate causes, together with the fact of their coexistence. 

 The one is as essential an ingredient as the other ; whether the 

 object be to discover the law of the effect, or only to explain 

 it. To deduce the laws of the heavenly motions, we require 

 not only to know the law of a rectilineal and that of a gravita- 

 tive force, but the existence of both these forces in the celestial 

 regions, and even their relative amount. The complex laws of 

 causation are thus resolved into two distinct kinds of elements : 

 the one, simpler laws of causation, the other (in the aptly 

 selected expression of Dr. Chalmers) collocations ; the collo- 

 cations consisting in the existence of certain agents or powers, 

 in certain circumstances of place and time. We shall hereafter 

 have occasion to return to this distinction, and to dwell on it 

 at such length as dispenses with the necessity of further insist- 

 ing on it here. The first mode, then, of the explanation of 

 Laws of Causation, is when the law of an effect is resolved into 

 the various tendencies of which it is the result, together with 

 the laws of those tendencies. 



3. A second case is when, between what seemed the 

 cause and what was supposed to be its effect, further observa- 

 tion detects an intermediate link; a fact caused by the ante- 

 cedent, and in its turn causing the consequent; so that the 

 cause at first assigned is but the remote cause, operating 

 through the intermediate phenomenon. A seemed the cause 

 of C, but it subsequently appeared that A was only the cause 

 of B, and that it is B which was the cause of C. For example : 

 mankind were aware that the act of touching an outward object 

 caused a sensation. It was subsequently discovered, that after 

 we have touched the object, and before we experience the 

 sensation, some change takes place in a kind of thread called 

 a nerve, which extends from our outward organs to the brain. 

 Touching the object, therefore, is. only the remote cause of our 



