THE LATEST STAGE 251 



But it is time to turn to other biological tendencies, 

 in which, perhaps, even greater philosophic interest 

 lies. Here too we have to trace an old 

 story in a new form. As the premature 

 determinist mechanical theory of life of the Greek 

 atomists gave way before the equally premature 

 vitalistic dogmas of Aristotle, so the still premature 

 mechanicism of the too ardent physiologists and 

 Darwinians of the nineteenth century shows signs of 

 yielding for the time before the continued analysis of 

 the problem of life. Charles Darwin himself, be it 

 noted, kept an open mind on questions authoritatively 

 answered by ultra-Darwinians, especially in Germany. 



The success of physiologists in co-ordinating many 

 functions of living organs with physical and chemical 

 changes led to a belief that life itself could be stated 

 completely in physical and chemical terms, and that 

 organic beings were but more complicated inorganic 

 machines. The fact that all living changes cannot 

 yet be explained by known physical principles is a 

 poor argument against a mechanical philosophy, for it 

 is supremely foolish to found our faith, in any depart- 

 ment of human thought, on mere gaps in knowledge, 

 some of which, at all events, can only be temporary. 



Each year sees an increase in the number of bodily 

 functions which can be described in physical and 

 chemical terms. In particular, the chemical action 

 of certain internal secretions poured into the blood is 

 being found to influence the functions of distant cells, 

 and thus to control such characters as stature, the 

 movement of the heart, even the development of the 

 brain. 



But, nevertheless, some biologists have held that 



