LEGACY OF THE GREEKS. 67 



feet forms, as well as the more perfect, were pro- 

 duced fortuitously. The misshapen, ill-combined 

 monsters were eliminated, one after the other, until 

 finally Nature produced animals capable of feeding 

 themselves and of propagation. Aristotle devel- 

 oped a wholly different notion of successive develop- 

 ment, more like the modern theory in the succession 

 of higher organisms from lower by descent and 

 modification. 



Together with these vague conceptions of the 

 fact of the gradual Evolution of life, was associated 

 as a theoretical explanation, first, the dimly fore- 

 shadowed 'Survival of the Fittest ' theory of Emped- 

 ocles, that the perfect forms were finally produced 

 as the result of a long series of fortuitous combina- 

 tions, and the wholly diverse theory of Aristotle 

 that there was no fortuity in Evolution, but that 

 the succession of forms was due to the action of an 

 internal perfecting principle originally implanted 

 by the Divine Intelligence. 



Finally, the principles of Adaptation, or fitness of 

 certain structures to certain ends, had been clearly 

 brought out, and gave rise to the distinct problem 

 of the origin or cause of adaptations. So that we 

 can find in Aristotle, most clearly stated, the great 

 question which has been one of the burning ques- 

 tions of Biology ever since — Whether or not 

 adaptations are due solely to the fortuitous com- 

 bination of parts ? 



Thus the Greeks left the later world face to face 



