SCIENTIFIC THOUGHT 11 



admiration of Paley's book. " The old argument 

 from design in nature as given by Paley," he 

 writes,* " which formerly seemed to me so con- 

 clusive, fails now that the law of Natural Selection 

 has been discovered. We can no longer argue that, 

 for instance, the beautiful hinge of a bivalve shell 

 must have been made by an intelligent being, like 

 the hinge of a door by man. There seems to be 

 no more design in the variability of organic 

 beings, and in the action of Natural Selection, 

 than in the course which the wind blows." And 

 this he says, though a few lines further down he 

 alludes to "the endless beautiful adaptations 

 which we everywhere meet with." 



When a new fact of the first importance or a 

 new theory of really wide-reaching importance, 

 is thrown into the scientific arena, it not only 

 creates a vast turmoil there, like the northern 

 blasts on the mountain tarn, but it also necessi- 

 tates a re-orientation of all kinds of matters, not 

 at first sight connected directly with the fact or 

 theory itself. In our own days the discovery of 

 radium and of radio-activity, has completely 

 altered the attitude of science towards all sorts of 

 subjects, even for example, the age and possible 

 destiny of the sun and the earth. We used to be 

 told that the earth was gradually cooling, and 

 would become an extinct " has-been " like the 

 moon. Yet now there is a school of scientific men 

 which declares that, so far from this being the case, 

 the earth is actually growing hotter and hotter in 

 its interior, and that, if this process goes on, as 



* Lije and Letters^ vol. i, p. 309. 



