284 The Study of Animal Life PART iv 



wonderful to think of his knowledge of the forms and ways 

 of life, or the insight with which he foresaw such useful dis- 

 tinctions as that between analogous and homologous organs, 

 or his recognition of the fact of correlation, of the advan- 

 tages of division of labour within organisms, of the gradual 

 differentiation observed in development. He planted seeds 

 which grew after long sleep into comparative anatomy and 

 classification. Yet with what sublime humility he says : "I 

 found no basis prepared, no models to copy. Mine is the 

 first step, and therefore a small one, though worked out with 

 much thought and hard labour." Aristotle was not an 

 evolutionist, for, although he recognised the changefulness of 

 life, the world was to him an eternal fact not a stage in a 

 process. 



" In nature, the passage from inanimate things to animals is so 

 gradual that it is impossible to draw a hard-and-fast line between 

 them. After inanimate things come plants, which differ from one 

 another in the degree of life which they possess. Compared with 

 inert bodies, plants seem endowed with life ; compared with 

 animals, they seem inanimate. From plants to animals the passage 

 is by no means sudden or abrupt ; one finds living things in the 

 sea about which there is' doubt whether they be animals or plants." 

 ~" Animals are at war with one another when they live in the same 

 place and use the same food. If the food be not sufficiently 

 abundant they fight for it even with those of the same kind. " 



3. Lucretius. Among the Romans Lucretius gave 

 noble expression to the philosophy of Epicurus. I shall 

 not try to explain his materialistic theory of the concourse 

 of atoms into stable and well-adapted forms, but rather 

 quote a few sentences in which he states his belief that the 

 earth is the mother of all life, and that animals work out 

 their destiny in a struggle for existence. He was a cosmic, 

 but hardly an organic evolutionist, for, according to his 

 poetic fancy, organisms arose from the earth's fertile bosom 

 and not by the gradual transformation of simpler predecessors. 



" In the beginning the earth gave forth all kinds of herbage and 

 verdant sheen about the hills and over all the plains ; the flowery 

 meadows glittered with the bright green hue, and next in order to 

 the different trees was given a strong and emulous desire of grow- 



