408 ON GENERATION. 



be subsequently determined, and whatever is necessary to the 

 constitution of a perfect animal arranged. For if this principle 

 were at any time extrinsic, and entered into the body at a sub- 

 sequent period, you would not only be in doubt as to the time 

 at which it entered, but as every part is distinct, you would 

 also see it as necessary that that should first exist from 

 which the other parts derive both increase and motion." The 

 same writer elsewhere l asserts : " This principle is a portion of 

 the whole, and not anything added, or included apart. For," 

 he proceeds, "the generation of the animal completed, does 

 this principle perish, or does it continue ? But nothing can be 

 shown existing intrinsically which is not a part of the whole 

 organized being, whether it be plant or animal; wherefore it 

 would be absurd to maintain that the principle in question 

 perished after the formation either of any one or of any number 

 of parts; for what should form those that were not yet produced? 

 Wherefore," he continues further, " they say not well who with 

 Democritus assert that the external parts of animals are those 

 first seen, and then the internal parts, as if they were rearing 

 an animal of wood and stone, for such a thing would include 

 no principle within itself. But all animals have and hold a 

 principle in their interior. Wherefore the heart is seen as the 

 first distinct part in animals that have blood ; for it is the origin 

 of all the parts, whether similar or dissimilar ; and the creature 

 that begins to feel the necessity of nourishment, must already 

 be possessed by the principle of an animal and a full-grown 

 foetus." 



From the above, it clearly appears that Aristotle recognizes 

 a certain order and commencement in animal generation, 

 namely, the heart, which he regards as the first produced and 

 first vivified part of the animal, and, like a son set free from 

 the tutelage of his parents, as self-sufficing and independent, 

 whence not only does the order of the parts proceed, but as that 

 by which the animal itself is maintained and preserved, receiving 

 from it at once life and sustenance, and everything needful to 

 the perfection of its being. For as Seneca says : 2 "In the 

 semen is comprised the entire cause of the future man; and the 

 unborn babe has written within it the law of a beard and a 



1 De Gen. Anim. lib. ii, cap. 1. * Nat. Quaest. lib. iii, cap. 29. 



