358 FOOT-NOTES TO EVOLUTION. 



perception pass over into action. In the lower forms we 

 have the devices, chiefly automatic, by which sensation 

 transmitted to the sensorium reappears as motion. In 

 like manner we find in man, besides these reflex trans- 

 fers and the reflex connections formed by habit, that 

 science becomes changed to art and knowledge to 

 power. Power and effectiveness are conditioned on ac- 

 curacy. Every failure in the sense organs, every form 

 of deterioration of the nerves, shows itself in reduction 

 of power. Reduced effectiveness manifests itself through 

 the processes of natural selection as lessened safety of 

 life. Thus the degeneration of the nervous system 

 through excesses, through precocious activity, or through 

 the effect of stimulants, shows itself in untrustworthy 

 perceptions, in uncontrolled muscles, and in general in- 

 security. Incidentally all these are recorded by fall in 

 social standing. Similar failure follows from any cause 

 impairing the recognition of the reality of external 

 things. The sober mind is necessary to secure life. In 



general all civilized men are well born. 

 The sober Th c()me Qf d stock> For thg 



mind. 



lineage of perversity, insanity, and even 



stupidity, is never a long one. The perverse, insane, 

 and the stupid live through the tolerance of others. 

 They can not maintain themselves, and in spite of char- 

 ity and the sense of conventionality, the mortality caused 

 by the fool-killer is something enormous. It is an essen- 

 tial element in race progress. It grows with increased 

 civilization, because of increasing complexity of condi- 

 tion. It is the chief offset for the systematic life-saving 

 which science makes possible. 



The recent " recrudescence of superstition," a strik- 

 ing accompaniment of an age of science, is in a sense de- 

 pendent on science. Science has made it possible. The 

 traditions of science are so diffused in the community 



