FROM THALES TO LUCRETIUS. 27 



the scheme of that philosopher. These, he says, 

 " have never existed," thus showing himself far in 

 advance of ages when unicorns, dragons, and such- 

 like fabled beasts were seriously believed to exist. 

 In one respect, more discerning than Aristotle, he 

 accepts the doctrine of the survival of the fittest as 

 taught by the sage of Agrigentum. For he argues 

 that since upon " the increase of some Nature set a 

 ban, so that they could not reach the coveted flower 

 of age, nor find food, nor be united in marriage," 

 ..." many races of living things have died out, and 

 been unable to beget and continue their breed." 

 Lucretius speaks of Empedocles in terms scarcely 

 less exaggerated than those which he applied to Epi- 

 curus. The latter is " a god " who first found out 

 that plan of life which is now termed wisdom, and 

 who by tried skill rescued life from such great bil- 

 lows and such thick darkness and moored it in so 

 perfect a calm and in so brilliant a light, ... he 

 cleared men's breasts with truth-telling precepts, and 

 fixed a limit to lust and fear, and explained what 

 was the chief good which we all strive to reach." As 

 to Empedocles, " that great country (Sicily) seems 

 to have held within it nothing more glorious than 

 this man, nothing more holy, marvellous, and dear. 

 The verses, too, of this godlike genius cry with a 

 loud voice, and make known his great discoveries, 

 so that he seems scarcely born of a mortal stock." 

 Continuing his speculations on the development 

 of living things, Lucretius strikes out in bolder and 



