THE CONFIRMATION OF THEORY 219 



only of the class here referred to, but of the most diverse 

 kinds, receive an intelligible explanation upon any theory, 

 they finally become a solid foundation for the theory itself. 

 Many theories of transcendent importance are held upon 

 indirect evidence of precisely this kind. We believe in 

 evolution, not because we see it taking place, but because 

 of the immense number of observed facts which it renders 

 intelligible, and the same is true of our confidence in the 

 Newtonian Theory. 



Whenever a naturalist approaches a problem in the 

 light of Natural Selection, and is able, by its aid, to pre- 

 dict a conclusion which subsequent investigation proves 

 to be correct, he is helping in the production of evidence 

 in favour of the theory. When a naturalist has found the 

 formula ' if Natural Selection be true, so-and-so ought to 

 happen', the safest of all guides into the Unknown, when 

 it has brought him success many times and in very diffe- 

 rent directions, when he knows that many other workers 

 in other fields of biological inquiry have had a similar 

 experience, he gradually comes to feel a profound con- 

 fidence in the permanent truth and the far-reaching 

 importance of the great theory which has served him so 

 well. 1 



The experiences of the naturalist, the student of living 

 nature, did not appeal to Huxley, and therefore it is not 

 remarkable that he was unable to feel much confidence in 

 Natural Selection. But those who are inspired by it will 

 never forget how much they owe to Huxley for the leading- 

 part he took in the great battles which had to be fought 

 before Evolution, and Natural Selection, too, were accorded 

 a fair hearing ; and his success went far beyond even 

 these issues. Whatever stirring and subversive ideas the 

 future may bring forth, we may be sure that they will 

 never suffer from the treatment accorded to the Origin 

 of Species ; and, far more than to any other single man, 

 the world owes this immense gain to Thomas Henry 

 Huxley. 



1 Poulton, Charles Darwin and the Theory of Natural Selection, 

 London, 1396, pp. 142, 143. 



