A Physicist on Evolution. 193 



increment to increment of infinitesimal change, and in this way 

 gradually breaks down your reluctance to admit that the exquisite 

 climax of the whole could be .\ result of natural selection. 



Mr. Darwin shirks no difficulty ; and, saturated as the subject 

 was with his own thought, he must have known, better than his 

 critics, the weakness as well as the strength of his theory. This 

 of course would be of little avail were his object a temporary 

 dialectic victory instead of the establishment of a truth which he 

 means to be everlasting. But he takes no pains to disguise the 

 weakness he has discerned ; nay, he takes every pains to bring it 

 into the strongest light. His vast resources enable him to cope 

 with objections started by himself and others, so as to leave the 

 final impression upon the reader's mind that if they be not com- 

 pletely answered they certainly are not fatal. Their negative force 

 being thus destroyed, you are free to be influenced by the vast 

 positive mass of evidence he is able to bring before you. This 

 largeness of knowledge and readiness of resource render Mr. 

 Darwin the most terrible of antagonists. Accomplished naturalists 

 have levelled heavy and sustained criticisms against him — not 

 always with the view of fairly weighing his theory, but with the 

 express intention of exposing its weak points only. This does not 

 irritate him. He treats every objection with a soberness and 

 thoroughness which even Bishop Butler might be proud to imitate, 

 surrounding each fact with its appropriate detail, placing it in its 

 proper relations, and usually giving it a significance which, as long 

 as it was kept isolated, failed to appear. This is done without a 

 trace of ill-temper. He moves over the subject with the passionless 

 strength of a glacier ; and the grinding of the rocks is not always 

 without a counterpart in the logical pulverization of the objector. 

 But though in handhng this mighty theme all passion has been 

 stilled, there is an emotion of the intellect incident to the discern- 

 ment of new truth which often colours and warms the pages of 

 Mr. Darwin. His success has been great ; and this imphes not 

 only the solidity of his work, but the preparedness of the public 

 mind for such a revelation. On this head a remark of Agassiz 

 impressed me more than anything else. Sprung from a race of 

 theologians, this celebrated man combated to the last the theory 

 of natural selection. One of the many times I had the pleasure of 

 meeting him in the United States was at Mr. Winthrop's beautiful 

 residence at Brookline, near Boston. Eising from luncheon, we all 

 halted as if by a common impulse in front of a window, and con- 

 tinued there a discussion which had been started at table. The 

 maple was in its autumn glory; and the exquisite beauty of the 

 scene outside seemed, in my case, to interpenetrate without dis- 

 turbance the intellectual action. Earnestly, almost sadly, Agassiz 

 turned and said to the gentlemen standing round, " I confess that 



