2oo The Evolution Hypothesis. 



matter and motion. But when pressed for a more 

 definite explanation, he answers with two discordant 

 voices. The direction of the movement, he tells us, 

 is due to the polarity of the physiological units 

 forming the contents of the cell : the directing power 

 Jay wrapped up in the germs themselves. This is 

 one answer. Elsewhere he accounts for the direction 

 df movement by the operation of the incident forces 

 >f the environment: these have determined whether 

 he primal cell should evolve into a Newton or an 

 ox. This is a second and quite conflicting answer. 

 It is for the evolutionist to reconcile them. 



It is the special claim of the evolution hypothesis 

 that it traces all the changes wrought in the organic 

 kingdoms to causes known to science rejecting all 

 other; but though the causes by which it is proposed 

 to account for all change may be of a kind embraced 

 in scientific knowledge, there is an utter failure in 

 the attempt to show, in any comprehensible way, the 

 mode of the operation of these causes in producing 

 the forms we see. It is no more unscientific to 

 assume a cause otherwise unknown to science, where 

 it is needful to do so in accounting for ascertained 

 facts, than it is to present as scientific a theory which 

 refers phenomena to known causes, but can furnish 

 no explanation as to how the results arrived at have 

 been reached. In that case, though the causes are 

 known causes, the law of their operation in the in- 

 stance under examination is unknown ; and science 



