The Message of Science. 81 



of altering the lower course of nature in his organism and 

 of directing the life of the cells of which his tissues are 

 composed? The question is a novel one, in this sense. 

 Hitherto, biologists have assured us that we must be con- 

 tent to be what inheritance would make us. That is the 

 old cell doctrine in a nutshell. Weismann and, in gen- 

 eral, the German, English and many American histologists 

 base their theories of life on this assumption, namely, that 

 the ordinary course of nature must be final as to man's 

 future. Nature is fate. 



But brain is higher nature, the acme, at present, of 

 natural development. Everything which makes man a 

 civilized and enlightened being has been obtained by brain 

 mastery of lower nature and the diversion of her ordinary 

 courses to his advantage. Why should we not expect to 

 thus arbitrarily change and facilitate the nutrition and 

 life of the cell ? In point of fact, that is what has been 

 done and is being done constantly in a hundred ways 

 already. The position of not a few biologists on this 

 question to-day is much as those who would argue that 

 since a man can walk -but fifty miles in a day, afoot, by 

 his natural means of locomotion, or swim but twenty 

 miles, he can never go to San Francisco in less than sixty 

 days, or reach Liverpool in less than five months. Three 

 hundred miles per day are as natural to brain as twenty 

 miles to muscle. 



It is to science that we look for the control of cell life. 



