WHAT IS DARWINISM? 159 



limits which cannot be passed. This Huxley 

 himself admits to be an insuperable objection. 

 So long as it exists, he says, Darwin's doctrine 

 must be content to remain a hypothesis"; it 

 cannot pretend to the dignity of a theory. 

 Another fact of like import is that varieties 

 artificially produced, if let alone, uniformly 

 revert to the simple typical form. It is only 

 by the utmost care they can be kept distinct. 

 All the highly prized varieties of horses, cattle, 

 sheep, pigeons, etc., without human control, 

 would be merged each class into one, with only 

 the slight differences occasioned by diversities 

 of climate and other external conditions. If in 

 the sight of man it is important that the words 

 of a book should be kept distinct, it is equally 

 evident that in the sight of God it is no less 

 important that the " units of nature " should 

 not be mixed in inextricable and indistinguish- 

 able confusion. 



Fifthly. The sudden appearance of new kinds 

 of animals is another fact which Palaeontologists 

 urge against the doctrine of evolution. Ac- 

 cording to the view of geologists great changes 

 have, at remote periods, occurred in the state 

 of the earth. Continents have been sub- 

 merged and the bottom of the sea raised above 



