Laplace 11 



present an outline picture of evolution as a whole, 

 and then to submit general reflections thereon. 



It is obvious that only high-brow mathematicians 

 can pronounce on the validity of these difficult 

 theories of the making of worlds, but it is important 

 that the outsider should realize that such theories are 

 advanced by competent experts and that the less 

 stable, like Laplace's, are being eliminated. 



The general significance of the experts' pictures 

 is clear ; they all point back to a nebula. The general 

 thought that cannot be repressed is that if the 

 potentiality of our earth and all that it contains was 

 in a knot on the spiral arm of a nebula there must 

 have been in the nebula more than met the eye — or 

 than would have met the eye had there been any far- 

 off astronomers to see. 



The story goes that Napoleon asked Laplace what 

 room there was for God in his celestial mechanics, to 

 which the astronomer answered that he "had no need 

 of that hypothesis." This is sometimes misunderstood 

 as an irreverent or atheistic declaration, but it was 

 neither. Laplace meant that the august concept of 

 God was foreign to the astronomer's "universe of 

 discourse." He meant that the words "God" and 

 "Gravitation" must not be used in the same breath. 

 He meant that the system of the stars is autonomous, 

 that it does not require any underpinning. It is not 

 like a clock that requires continual winding-up and 

 continual regulation, though it may well be that the 

 religious mind is right in believing that the world 

 is the embodiment of a Divine Thought and that it 



