GENERATION OF ANIMALS, II. iv. 



father. That is why it must have a first principle, 

 from which also the subsequent ordering of the 

 animal's body is derived. Otherwise, supposing this 

 principle is to come in at some moment from outside 

 and take up its position inside later on, then we may 

 L'U be puzzled at what moment this is to happen, 

 iid also we may point out that of necessity the first 

 principle must be present at the outset, at the time 

 when each of the parts is being separated from the 

 rest, since the growth and movement of the other 

 parts are derived from it. That is why those people 

 are wrong who, like Democritus," hold that the 

 external parts of animals become distinct first, and 

 then the internal ones. They might be speaking of 

 animals carved out of wood or stone, the sort of things 

 which have no first principle at all, whereas living 

 animals all have such a principle, and it is inside 

 them. On this account in all blooded animals it is 

 the heart which can first be seen as something dis- 

 tinct, as this is the first principle both of the " uni- 

 f(jrm " and of the " non-uniform " parts ^ — since this 

 is justifiably designated as first principle of the animal 

 or organism from the moment when it begins to need 

 nourishment,'^ for of course that which exists grows,'^ 

 and, for an animal, the ultimate form of nourish- 

 ment is blood or its counterpart. Of these fluids 

 the blood-vessels are the receptacle,^ and therefore 



T:>5 a 13-26 (where again the reading with Sv should be kept 

 in 735 a 23). Here the point is clearly made that, once a 

 thing has come into being (yenjrai), it must of necessity grow. 

 See also note on 744 b 36. 



' The blood-vessels distribute the " ultimate nourishment " 

 to the parts of the body, which, as Aristotle says (743 a 1), are 

 moulded round them like a wax figure round a core or 

 foundation, and are formed out of them. 



195 



