76 SECTIONAL ADDRESSES 



become gradually ingrained ; just as practices oft repeated become in- 

 eradicable habits. In contrast with modern municipal tendencies, trolley- 

 buses are transmuted to trams. 



The several characters of an organism are at once independent and 

 inseparable ; each can follow its own line of development, but unless a 

 balance is kept within the whole series, collapse is certain. ' Just as different 

 groups of organisms show very different evolutionary speed, so the various 

 structures in a single organism become modified at varying rates. The 

 attainment of mature perfection from a stage of immaturity can never be 

 more than a transient phase on the way to a fresh disproportion com- 

 parable with senility. 



Structures, and with them the organisms to which they belong, grow old, 

 exhausted or hypertrophied by their own intrinsic expenditure of evolu- 

 tional ' effort ' amid an ever-fluctuating embarrassment of circumstance. 



We come to the conclusion that the oracular recommendation to know 

 ourselves is a guide to the secret of evolution. Physically and (in the 

 human case) psychologically we live our lives as compromises between 

 hereditary tendencies and environmental requirements. As we grow 

 older our accumulated load of compromise becomes an obsession, reducing 

 our capacity for further efforts of the kind ; and our environment never 

 tires in its changefulness. 



If we consider these principles in the light of the struggle for existence, 

 we find that those types which can attain the most perfect harmony with 

 their environment will flourish proportionately. But their success brings 

 Nemesis in its train ; for speedy evolution towards dominance implies 

 continuous speed ; the perfection point is passed by the same momentum 

 that reached it. Undoubtedly the victor in the struggle for existence 

 wins the prize : but the prize is death. 



When we attempt to apply to human affairs the principles of evolution 

 as shown in Palaeontology, many difficulties appear. Not the least of 

 these is the impossibility of a dispassionate outlook ; we are proverbially 

 unable to see ourselves as others see us. Another serious difficulty arises 

 from the shortness of the time during which our species has existed, and 

 the paucity of reliable evidence that it has left of its history. 



At the outset we must admit that the basis of our analysis of mankind 

 will be on a different plane from that which we employ in the case of other 

 organisms. Morphological and physiological characters change so slowly 

 that we cannot expect to find much alteration during our brief career ; 

 and in any case there is practically no evidence of that sort available. 

 But if the conclusions already reached as to the universality of the law 

 of evolution are accepted, it matters not a whit which particular attribute 

 of an organism we select for study. Behaviour is but an expression of 

 the reaction between the qualities of an organism and its environment, 

 and civilisation is a kind of behaviour. This argument is not so specious 

 as it may appear, for the evidence available to check its validity is ample. 



Before following that line further, it will be well to attempt an estimate 

 of the qualities of the human species as they appear to a palaeontologist. 

 This is a dangerous part in this address ; for I am bound to omit, for the 



