536 INDUCTION. 



medium in which it subsists, together with the 

 peculiar vital laws of the different tissues constituting 

 the organic structure. In other cases, really far more 

 simple than these, it was much less obvious in what 

 quarter the causes were to be looked for : as in the 

 great case of the celestial phenomena. Until, by 

 combining the laws of certain causes, it was found 

 that those laws explained all the facts which expe- 

 rience had proved concerning the heavenly motions, 

 and led to predictions which it always verified, man- 

 kind never knew that those were the causes. But 

 whether we are able to put the question before or 

 not until after we have become capable of answering 

 it, in either case it must be answered ; the laws of 

 the different causes must be ascertained, before we 

 can proceed to deduce from them the conditions of 

 the effect. 



The mode of ascertaining these laws neither is, 

 nor can be, any other than the fourfold method of 

 experimental inquiry, already discussed. A few 

 remarks on the application of that method to cases 

 of the Composition of Causes, are all that is requisite. 



It is obvious that we cannot expect to find the 

 law of a tendency, by an induction from cases in 

 which the tendency is counteracted. The laws of 

 motion could never have been brought to light from 

 the observation of bodies kept at rest by the equi- 

 librium of opposing forces. Even where the tendency 

 is not, in the ordinary sense of the word, counteracted, 

 but only modified, by having its effects compounded 

 with the effects arising from some other tendency or 

 tendencies, we are still in an unfavourable position for 

 tracing, by means of such cases, the law of the ten- 

 dency itself. It would have been difficult to discover 

 the law that every body in motion tends to continue 



