102 FROM THE GREEKS TO DARWIN 



Internal Perfecting Principle 



Aristotle developed a wholly different notion 

 of successive development, more like the modern 

 theory in the succession of higher organisms from 

 lower by descent and modification; he set forth 

 the wholly diverse theory that there was no 

 fortuity in Evolution, but that the succession of 

 forms was due to the action of an internal per- 

 fecting principle originally implanted by the 

 Divine Intelligence. So that we find in Aristotle, 

 most clearly stated, what has been one of the 

 burning questions of biology ever since — 

 whether adaptations are due solely to the for- 

 tuitous combination of parts or to an internal 

 perfecting principle. 



Thus the Greeks left the later world face to 

 face with the problem of the causation of life in 

 three forms: first, whether intelligent Design is 

 constantly operating in Nature ; second, whether 

 Nature is under the operation of natural causes 

 due from the beginning to the laws of chance, 

 and containing no evidences of Design, even in 

 their origin ; and third, whether Nature is under 

 the operation of natural causes originally im- 

 planted by intelligent Design. 



