LAWS OF NATURE. 353 



dently of specific experience, through our knowledge of the 

 simpler ones from which it results ; though, for reasons which 

 will appear hereafter, verification by specific experience would 

 still he desirable, and might possibly be indispensable. 



Complex uniformities which, like this, are mere cases of 

 simpler ones, and have, therefore, been virtually affirmed in 

 affirming those, may with propriety be called laws, but can 

 scarcely, in the strictness of scientific speech, be termed Laws 

 of Nature. It is the custom in science, wherever regularity of 

 any kind can be traced, to call the general proposition which 

 expresses the nature of that regularity, a law ; as when, in 

 mathematics, we speak of the law of decrease of the successive 

 terms of a converging series. But the expression law of 

 nature has generally been employed with a sort of tacit refer- 

 ence to the original sense of the word law, namely, the ex- 

 pression of the will of a superior. When, therefore, it appeared 

 that any of the uniformities which were observed in nature, 

 would result spontaneously from certain other uniformities, no 

 separate act of creative will being supposed necessary for the 

 production of the derivative uniformities, these have not usu- 

 ally been spoken of as laws of nature. According to one 

 mode of expression, the question, What are the laws of nature ? 

 may be stated thus : What are the fewest and simplest as- 

 sumptions, which being granted, the whole existing order of 

 nature would result ? Another mode of stating it would be 

 thus : What are the fewest general propositions from which 

 all the uniformities which exist in the universe might be de- 

 ductively inferred ? 



Every great advance which marks an epoch in the progress 

 of science, has consisted in a step made towards the solution 

 of this problem. Even a simple colligation of inductions 

 already made, without any fresh extension of the inductive 

 inference, is already an advance in that direction. When 

 Kepler expressed the regularity which exists in the observed 

 motions of the heavenly bodies, by the three general proposi- 

 tions called his laws, he, in so doing, pointed out three simple 

 suppositions which, instead of a much greater number, would 

 suffice to construct the whole scheme of the heavenly motions, 

 VOL. i. 23 



