io8 Species; or, Darwinism. 



of having proved the point is borrowed from another 

 side; when, finding things to suit their anticipations, 

 the scientists argue that evolution must be true 

 because the facts are shown to be in entire accord- 

 ance with it. This is what Professor Huxley calls 

 the demonstrative evidence of evolution. And it 

 would be so if all the facts were shown to be in 

 perfect accordance with the theory, as all the celes- 

 tial phenomena are in keeping with the Copernican 

 system, which is consequently no longer an hypoth- 

 esis but a thesis. But not so, if only some facts 

 agree, while others and many others contradict the 

 theory. Then the hypothesis is disproved; and to 

 take it as demonstrated on the strength of some 

 coincidences is a fallacy of sophistical induction, 

 like that which we noted in geology (No. 16). And, 

 thirdly, here comes in the use of another sophism, 

 when those very facts, cited as being in perfect ac- 

 cord with the theory, are so indeed, but are in 

 entire accord with a different and contradictory 

 theory. Thus, Professor Huxley finds his demon- 

 strative evidence of evolution in the series of fossil 

 horses, representing different stages of evolution up 

 to the recent, modern form. In the fourth of his 

 American lectures on the subject, he shows the 

 fossil forms, orohippus, mesohippus, miohippus, 

 hipparion, pliohippus, all verging in the same direc- 

 tion, and finally the series terminates in the modern 

 horse. This is just, he says, what evolution would 

 require. One may answer: But it is just what 



