GENERATION OF ANIMALS, II. v. 



and bring it to completion : if it could, the exist- 

 ence of the male would have no purpose, and Nature 

 does nothing which lacks purpose. Hence in such 

 animals the male always completes the business of 

 generation — it implants sentient Soul, either acting 

 by itself directly or by means of semen. As the 

 parts of the animal to be formed are present poten- 

 tially in the matter," once the principle of move- 

 ment has been supplied, one thing follows on after 

 another without interruption, just as it does in the 

 " miraculous " automatic puppets. ** And the mean- 

 ing of the statement, made by some of the physio- 

 logers,-' about like " making its way to hke,"** must be 

 taken to be not that the parts of the body " move " ^ 

 in the sense of changing their position, but that while 

 remaining in the same position they undergo " altera- 

 tion " f as regards softness, hardness, colour, and the 

 other differences which belong to the uniform parts ; 

 that is, they become in actuality what previously all 

 along they had been potentially. The first to be formed 

 is the " principle," which in blooded animals is the 

 heart and in the others the counterpart of the heart, 

 as I have said many times over. There can be no 

 doubt about this, because our senses tell us that it 

 is the first thing fornied ; but the truth of it is con- 

 firmed by what happens when the creature dies : the 

 heart is the place where life fails last of all ; and we 

 find universally that what is the last to be formed is 

 the first to fail, and the first to be formed is the last 

 to fail.' It is as though Nature were a runner, cover- 

 ing a double course there and back, and retracing her 



» Cor primum vivens ultimiim morions : cf. Ebstein et at.. 

 Mitt, zur Gesch. der Medizin nnd Naturw.' 19 (1920), 102, 

 219, 305. 



207 



