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SCIENCE 



[N. S. Vol. XXXVIII. No. 974 



methods, and cultured man by methods 

 more refined, to put out of his way sex 

 rivals so that his own life may be con- 

 tinued through offspring. The life of the 

 species is further assured by the protective 

 action exercised over the young by the 

 adults of the species. As soon as the 

 youngest offspring is able successfully to 

 carry on his own struggle with environ- 

 ment there is no longer need for the 

 parent, and the parent enters therefore 

 the stage of disintegration. The average 

 length of life in any species is the sum of 

 the years of immaturity, plus the years of 

 female fertility, plus the adolescent years 

 of the offspring. 



The stimuli resulting from these two 

 dominant instincts are now so overpower- 

 ing as compared with all other environmen- 

 tal stimuli that the mere possession of ade- 

 quate knowledge of the damaging effects of 

 certain actions as compared with the sav- 

 ing effects of others will (other things being 

 equal) lead the individual to choose the 

 right, — the self- and species-preservative 

 course of action, instead of the wrong, — 

 the self- and species-destructive course of 

 action. 



The dissemination of the knowledge of 

 the far-reaching deleterious effects of pro- 

 tracted emotional strain, of overwork, and 

 of worry will automatically raise man's 

 threshold to the damaging activating 

 stimuli causing the strong emotions, and 

 will cause him to avoid dangerous strains 

 of every kind. The individual thus pro- 

 tected will therefore rise to a plane of poise 

 and efficiency far above that of his uncon- 

 trolled fellows, and by so much will his 

 efficiency, health and happiness be aug- 

 mented. 



A full acceptance of this theory can not 

 fail to produce in those in whose charge 

 rests the welfare of the young, an over- 

 whelming desire to surround children with 

 those environmental stimuli only which 



will tend to their highest ultimate welfare. 



Such is the stimulating force of tradi- 

 tion that many who have been educated 

 under the tenets of traditional beliefs will 

 oppose these hypotheses — even violently, it 

 may be. So they have opposed them; so 

 they opposed Darwin ; so they have opposed 

 all new and apparently revolutionary doc- 

 trines. Yet these persons themselves are 

 by their very actions proving the efficiency 

 of the vital principles which we have enun- 

 ciated. What is the whole social welfare 

 movement but a recognition on the part of 

 municipalities, educational boards, and re- 

 ligious organizations of the fact that the 

 future welfare of the race depends upon 

 the administration to the young of forceful 

 uplifting environmental stimuli. 



There are now, as there were in Dar- 

 win's day, many who feel that man is de- 

 graded from his high estate by the concep- 

 tion that he is not a reasoning, willing be- 

 ing, the result of a special creation. But 

 one may wonder indeed what conception of 

 the origin of man can be more wonderful or 

 more inspiring than the belief that he has 

 been slowly evolved through the ages, and 

 that all creatures have had a part in his 

 development; that each form of life has 

 contributed and is contributing stUl to his 

 present welfare and to his future advance- 

 ment. 



EECAPITULATION 



Psychology — the science of the human 

 soul and its relations — under the mechanis- 

 tic theory of life, must receive a new defini- 

 tion. It becomes a science of man's activi- 

 ties as determined by the environmental 

 stimuli of his phylogeny and of his 

 ontogeny. 



On this basis we postulate that through- 

 out the history of the race nothing has been 

 lost, but that every experience of the race 

 and of the individual has been retained for 

 the guidance of the individual and of the 

 race; that for the accomplishment of this 



