BOOK II 



I HAVE already described with considerable detail P'lrpose and 

 in my Researches upon Animals what and how many the treatise. 

 are the parts of which the various animals are 

 composed. We must now leave on one side what 

 was said there, as our present task is to consider 

 what are the causes through M'hich each animal is as 

 I there described it. 



Three sorts of composition can be distinguished. 

 (1) First of all '^ we may put composition out of the 

 Elements (as some call them), viz. Earth, Air, Water, 

 Fire ; or perhaps it is better to say dynameis ^ instead 

 of Elements — some of the dynameis, that is, not all, 

 as I have stated pre\-iously elsewhere.'^ It is just 

 these four, the fluid substance, the solid,*^ the hot, and 

 the cold, which are the matter of composite bodies ; 

 and the other differences and qualities — such as 

 heaviness lightness, firmness looseness, roughness 

 smoothness, etc. — which composite bodies present 

 are subsequent upon these. (2) The second sort of 

 composition is the composition of the "uniform"* 

 substances found in animals (such as bone, flesh, 

 etc.). These also are composed out of the primary 



appropriate : in others, " moist " and " dry " (the traditional 

 renderings). Aristotle defines them at De gen. and corr. 

 329 b 30. See also below, 6-1-9 b 9. I have normally trans- 

 lated them " fluid " and " solid " throughout. 



• " Uniform," " non-uniform"; see Introduction, p. 28. 



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