The Evolution of the Sciences 



cms agitation; a lamp, a hot body (and all 

 bodies are more or less hot), emit the waves 

 which constitute radiated light or heat. How 

 could they do this if their elements weie frozen 

 in eternal repose? If we consider matter to be 

 dead it is because we observe it from too great 

 a distance, or because our eyes are not sharp 

 enough. In the same way if we could see at a 

 distance of ten miles an amphitheatre full of 

 people the whole would stiike us as a motionless 

 mass. Experience, therefore, proves that matter 

 is never at rest, and though we postulate that its 

 movement is due to forces which we have never 

 seen and which we can only define as the cause 

 of this movement, that is simply a hypothesis, a 

 hypothesis which we certainly have the right to 

 make but which we must feel to be fragile. 



Something remains to be added to all these 

 arguments. Classical science tells us that every- 

 thing possessed of inertia is matter, everything 

 not possessing inertia is immaterial; heat is 

 immaterial, because it is incapable of over- 

 shooting its position of equilibrium, of ascending 

 from a cold body to a hot one after having 

 descended from a hot body to a cold one. 



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