68 De Vi PJiysica 



the necessary scientific preliminary, that the 

 past shall and must be explained in terms 

 of the present, because we know the present 

 and not the past, sounds at first like the 

 truth : but it is in reality the antipodes of 

 science : it is precisely analogous to the de- 

 mand, that true science requires the child 

 to be explained in terms of the old man, 

 because we know only the old man. But 

 on the contrary, if we really have no know- 

 ledge, save of the old man, then instead of 

 ridiculously endeavouring to get an expla- 

 nation of the child in terms of the old 

 man, and calling this science, let us rather 

 frankly say at once, that science is here 

 unattainable, and that knowledge of the 

 child is beyond our ken. The wildest con- 

 jectures, though wholly unscientific, may 

 possibly be true, or near the truth : but 

 logical reasoning on Lyellian principles 

 must issue in what is false : because it is 



