A Working Hypothesis 103 



experiments in selective breeding had not produced varieties 

 which were more or less infertile ; and that insecurity remains 

 up to the present time. But, with any and every critical doubt 

 which my sceptical ingenuity could suggest, the Darwinian 

 hypothesis remained incomparably more probable than the 

 creation hypothesis. And if we had none of us been able to 

 discern the paramount significance of some of the most patent 

 and notorious of natural facts, until they were, so to speak, 

 thrust under our noses, what force remained in the dilemma 

 —creation or nothing? It was obvious that, hereafter, the 

 probability would be immensely greater that the links of 

 natural causation w^ere hidden from our purblind eyes, than 

 that natural causation should be unable to produce all the 

 phenomena of nature. The only rational course for those who 

 had no other object than the attainment of truth, was to accept 

 ' Darwinism ' as a working hypothesis, and see what could be 

 made of it. Either it would prove its capacity to elucidate the 

 fact of organic life, or it would break down under the strain. 

 This was surely the dictate of common sense, and for once 

 common-sense carried the day. The result has been that com- 

 plete volte-face of the whole scientific world which must seem 

 so surprising to the present generation. I do not mean to say 

 that all the leaders of biological science have avowed them- 

 selves Darwinians ; but I do not think that there is a single 

 zoologist, or botanist, or palaeontologist, among the multitude 

 of active workers of this generation, who is other than an 

 evolutionist profoundly influenced by Darwin's views. What- 

 ever may be the ultimate fate of the particular theory put forth 

 by Darwin, I venture to affirm that, so far as my knowledge 

 goes, all the ingenuity and all the learning of hostile critics 

 has not enabled them to adduce a solitary fact of which it can 

 be said that it is irreconcilable with the Darwinian theory. 

 In the prodigious variety and complexity of organic nature, 

 there are multitudes of phenomena which are not deducible 

 from any generalisation we have yet reached. But the same 

 may be said of every other class of natural objects. I believe 

 that astronomers cannot yet get the moon's motions into per- 

 fect accordance with the theory of gravitation." 



These quotations make plain the historical fact that 



