BIOLOGY IN ITS WIDER ASPECTS 1335 



550 B.C.) is often quoted by eugenists, but is well worth recalling 

 once more: 



We look for rams and asses and stallions of good stock, and one 

 believes that good will come from good; yet a good man minds not to 

 wed an evil daughter of an evil sire, if he but give her much wealth. 

 . . . Wealth confounds our stock. Marvel not that the stock of our 

 folk is tarnished, for the good is mingling with the base. 



Plato would have the State intervene to mate best with best and 

 worst with worst; also that the families of the former should be 

 large, and rewarded by the Government, while those of the others 

 should be put away. Aristotle also developed the idea on political 

 lines, as more interested in economic than biological aspects of 

 marriage; but he held firmly to the doctrine that the state should 

 feel free to intervene in the interests of reproductive selection. 



All historians agree as to our vast losses of the heritages of ancient 

 thought and vkill from past civilisations; and here i surely one of 

 them. The "dark ages" into which Europe fell with the destruction 

 of Greek and Roman culture by the barbarian invasions are com- 

 monly thought of as long past; but, as matter of fact, is not their 

 darkness still upon us — ^for each and every vital thought and 

 achievement which we have neither recovered from the past nor 

 yet worked out anew for ourselves ? 



It is well indeed to do both, and as regards the greater civilisations 

 especially. Thus we have just seen how the Ol5mipian Gods express 

 life-phases akin to those of embryology and ordinary anthropology ; 

 and though our advances towards animal and plant breeding are 

 now more skilled and sure than were those of our predecessors, we 

 may still have something to learn from these, as surely for humanity. 



EVILS IN ORGANIC LIFE.— How far can the preceding outline 

 of human and social evils contribute towards the understanding of 

 the difficulties of organic life? A main one is that of finding sub- 

 sistence for increasing population, and this as checked accordingly. 

 But to this difficulty of Malthus we have the qualified yet definite 

 Darwinian optimism, of progress by natural selection; and also 

 Spencer's insistence on the rise of individuation in the animal world 

 in association with a diminishing rate of reproduction — so that here 

 are elements of consolation for the (sometimes surely excessive) fears 

 of eugenists. (See sections on Heredity, Eugenics, etc.) 



As we have already pointed out, animal life shows but little of 

 disease, compared with man, though enough for substantial be- 

 ginnings of comparative pathology. Yet when these are viewed 

 from the more general viewpoint of variation in general, a certain 

 element of hopeful interpretation arises even here. Thus the natural 

 rise of temperature, observable in cold-blooded animals in activity, 



