202 HUXLEY AND NATURAL SELECTION 



most ardent votary of science holds his firmest convictions 

 . . . because his experience teaches him that whenever he 

 chooses to bring these convictions into contact with their 

 primary source, Nature — whenever he thinks fit to test 

 them by appealing to experiment and to observation — 

 Nature will confirm them.' But with respect to Natural 

 Selection, as it required the student of living nature to 

 discover the principle itself, so the experience which brings 

 confidence in it is that mainly of the naturalist. The 

 strongest confidence in the abiding truth of a theory is 

 gained by those whose imagination has been inspired by 

 it. Every verified prediction made in the light of Natural 

 Selection places the theory upon a more secure foundation. 

 That foundation has been growing firmer for nearly half 

 a century ; but, as I hope to show by illustration in the 

 remaining section of this address, the increasing confidence 

 is not so much due to the facts which are the province 

 of the anatomist as those which form the everyday 

 experience of the naturalist, of the man who studies 

 animal form and change and instinct, not in relation to 

 the single individual or the single species, but in rela- 

 tion to the whole environment, and especially the world 

 of living organisms. Huxley's researches, determined 

 by the bent of his mind, were not of this kind, they were 

 physiological, anatomical, and palaeontological. To use 

 his son's words, ' It was the engineering side of nature, 

 the unity of plan of animal construction, worked out in 

 infinitely varying detail which engrossed him.' l Again, 

 'walking once with Hooker in the Rhone valley, where 

 the grass was alive with red and green grasshoppers, he 

 said, " I would give anything to be as interested in them 

 as you are." ' 2 



It is no wonder, therefore, that, as Huxley's experience 

 was not that of the naturalist, the confidence in Natural 

 Selection of which I have spoken was not for him. 



I now propose to draw your attention to a few examples 

 of that adaptation which more than anything else kept 

 Darwin orthodox, but in the end furnished him with the 



1 Life and Letters of T. H. Huxley, vol. ii, p. 443. 



2 Ibid. p. 443. 



