The Conditions of Life and Death. 87 



from thermic, electric, and other forms of energy. 

 This was the meaning attached to the phrase by the 

 disciples of Haller, by Louis Dumas (1765-1813), by 

 Reil (1759-1813), and the other early vitalists. It can 

 only be said that an appeal to such a force violates the 

 scientific method, and abandons the scientific problem. 

 Again and again, in regard to particular points, subse- 

 quent progress has shown that the loss of faith in 

 science was premature. 



According to the hypothesis of vitalism the pheno- 

 mena of life are inexplicable apart from a special vital 

 force exclusively resident in organisms, and different 

 from the chemico-physical energies of the inanimate 

 world. Thus the great pathologist and anatomist 

 Henle (d. 1885) believed in a non-material agent associ- 

 ated with the organism, "presiding over the metabolism 

 of the body, capable of reproducing the typical form, and 

 of endless partition without diminution of intensity". 



It is altogether an error to suppose that a refusal 

 to believe in such a special "vital force" implies 

 materialism. The questions are quite separate; the 

 former has to do with scientific method, the latter is a 

 philosophical theory. Thus Huxley was certainly no 

 believer in "a vital force", yet he was clearly an 

 idealist; and the same might be said of many. 



Every physiologist will, I believe, admit that he can- 

 not at present give a physico-chemical interpretation 

 of contractility or of irritability, of digestion or of 

 absorption, of respiration or of circulation. What he 

 can give is a partial analysis of these functions in 

 simpler terms. This must remain the case until we 

 discover the secret of the synthesis which the simplest 

 unicellular organism expresses. In regard to some 

 points the translation of vital functions into physico- 

 chemical processes seems further off than it did twenty 

 years ago, but that is because we are less readily 

 satisfied. 



The " neo-vitalists ", such as Bunge and Rindfleisch, 

 emphasize the fact that there is no present possibility 

 of giving a complete chemico-physical restatement of 

 any observed function; that there are always residual 



