8 THE NEW PHYSIOLOGY. 



from a previous germ-cell. What must the "mechanism" 

 of this cell have been ? And that of its endless prede- 

 cessors ? We have reached the Euclidean reductio ad 

 absurd ion. 



I might strengthen my argument by referring to the 

 further difficulty over any physico-chemical conception 

 of what occurs in the sexual fusion of the male and 

 female cell, or in the process of partial reproduction after 

 injury, or in the facts established by Driesch and others 

 with regard to the extraordinary reproductive powers 

 of each cell in developing embryos. But I have pur- 

 posely confined my references to more simple and well- 

 known facts ; for the more simply the argument can 

 be put, the better. I confess that as a physiologist I 

 am struck with amazement at the manner in which 

 heredity is often discussed by contemporary writers 

 who endeavour to treat the subject from a mechanistic 

 standpoint. Sometimes, indeed, the germ-cell is acknow- 

 ledged to be a complicated structure, but at other times 

 it is treated as a " plasma," which can be mixed with 

 other " plasma," divided, or added to, as if for all the 

 world it were so much treacle ! I have tried to place 

 clearly before you the assumptions in connection with 

 heredity which, to my mind, make the physico-chemical 

 theory of life unthinkable, even if it be tenaciously clung 

 to in connection with those ordinary physiological 

 phenomena where, as already explained, it has proved so 

 disappointing. 



Our aim as physiologists is to render physiological 

 phenomena intelligible — in other words, to obtain general 

 conceptions as to their nature. The point now reached 

 is that the conceptions of physics and chemistry are in- 



