114 SCIENCE AND PSEUDO-SCIENCE m 



quite conceivable, as has recently been pointed 

 out, that some of the lowest forms of life may 

 be immortal, after a fashion. However this 

 may be, I would further ask, supposing " all men 

 are mortal " to be a real law of nature, where and 

 what is that to which, with any propriety, the 

 title of "compelling force" of the law can be 

 given ? 



On page 69, the Duke of Argyll asserts that the 

 law of gravitation " is a law in the sense, not 

 merely of a rule, but of a cause." But this 

 revival of the teaching of the "Vestiges" has 

 already been examined and disposed of; and when 

 the Duke of Argyll states that the " observed 

 order " which Kepler had discovered was simply a 

 necessary consequence of the force of "gravita- 

 tion," I need not recapitulate the evidence which 

 proves such a statement to be wholly fallacious. 

 But it may be useful to say, once more, that, at 

 this present moment, nobody knows anything 

 about the existence of a " force " of gravitation 

 apart from the fact ; that Newton declared the 

 ordinary notion of such force to be inconceivable ; 

 that various attempts have been made to account 

 for the order of facts we call gravitation, without 

 recourse to the notion of attractive force ; that, if 

 such a force exists, it is utterly incompetent to 

 account for Kepler's laws, without taking into the 

 reckoning a great number of other considerations ; 

 and, finally, that all we know about the " force " 



