CHAP. V . Social Life of Animals 93 



Hobbesian war of each against all was the normal state of 

 existence," let me place that of Kropotkine, to whose admir- 

 able discussion of mutual aid among animals I again 

 acknowledge my indebtedness. 



" Life in societies is no exception in the animal world. 

 It is the rule, the law of nature, and it reaches its fullest 

 development with the higher Vertebrates. Those species 

 which live solitary, or in siriall families only, are relatively 

 few, and their numbers are limited. . . . Life in societies 

 enables the feeblest mammals to resist, or to protect them- 

 selves from, the most terrible birds and beasts of prey ; 

 it permits longevity ; it enables the species to rear its pro- 

 geny with the least waste of energy, and to maintain its 

 numbers, albeit with a very slow birth-rate ; it enables the 

 gregarious animals to migrate in search of new abodes. 

 Therefore, while fully admitting that force, swiftness, pro- 

 tective colours, cunning, and endurance of hunger and cold, 

 which are mentioned by Darwin and Wallace as so many 

 qualities making the individual or the species the fittest 

 under certain circumstances, we maintain that under any 

 circumstances sociability is the greatest advantage in the 

 struggle for life. . . . The fittest are thus the most soci- 

 able animals, and sociability appears as the chief factor of 

 evolution, both directly, by securing the well-being of the 

 species while diminishing the waste of energy, and indirectly 

 by favouring the growth of intelligence. . . . Therefore 

 combine — practise mutual aid ! That is the surest means 

 for giving to each and to all the greatest safety, the best 

 guarantee of existence and progress — bodily, intellectual, 

 and moral. That is what nature teaches us." 



10. A Note on "The Social Organism." — It is com- 

 mon nowadays to speak of society as " the social organism," 

 and the metaphor is not only suggestive but convenient 

 — suggestive because it is profitable to biologist and soci- 

 ologist alike to follow out the analogies between an organism 

 and society, convenient because there is among organisms 

 . — in aggregates like sponges, in perfected integrates like 

 birds — a variety sufficient to meet all grades and views of 

 society, and because biologists differ almost as much in 



