1. THE POSSIBLE ASPECTS OF HISTORY 



OF course, we could select one definite volume in space 

 and call all the consecutive stages which it goes through, 

 its history : it then would be part of its history that a 

 cloud was formed in it, or that a bird passed through it 

 on the wing. But it would hardly be found very 

 suggestive to write the history of space -volumes. In fact, 

 it is to bodies in space that all history actually relates, at 

 least indirectly, for even the history of sciences is in some 

 respect the history of men or of books. It may suffice for 

 our analysis to understand here the word body in its 

 popular sense. 



Now in its relation to bodies history may have the 

 three following aspects, as far as anything more than a 

 simple enumeration comes into account. Firstly, it may 

 relate to one and the same body, the term body again to be 

 understood popularly. So it is when the individual history 

 of the organism is traced from the egg to the adult, or 

 when the history of a cloud or of an island or of a volcano 

 is written. Secondly, the subject-matter of history may be 

 formed by the single units of a consecutive series of bodies 

 following each other periodically. To this variety of history 

 the discoveries of Mendel and his followers would belong in 

 the strictest sense, but so does our hypothetical phylogeny 



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