II PSEUDO-SCIENTIFIC REALISM 85 



ception held undisputed sway ; living matter was 

 endowed with " vital force," and that accounted for 

 everything. Whosoever was not satisfied with 

 that explanation was treated to that very " plain 

 argument " "confound you eternally " where- 

 with Lord Peter overcomes the doubts of his 

 brothers in the " Tale of a Tub " " Materialist " was 

 the mildest term applied to him fortunate if he 

 escaped pelting with " infidel " and " atheist." 

 There may be scientific Rip Van Winkles about, 

 who still hold by vital force ; but among those 

 biologists who have not been asleep for the last 

 quarter of a century " vital force " no longer 

 figures in the vocabulary of science. It is a patent 

 survival of realism ; the generalisation from ex- 

 perience that all living bodies exhibit certain 

 activities of a definite character is made the basis 

 of the notion that every living body contains an 

 entity, " vital force/' which is assumed to be the 

 cause of those activities. 



It is remarkable, in looking back, to notice to 

 what an extent this and other survivals of 

 scholastic realism arrested or, at any rate, impeded 

 the application of sound scientific principles to 

 the investigation of biological phenomena. When 

 I was beginning to think about these matters, the 

 scientific world was occasionally agitated by 

 discussions respecting the nature of the " species " 

 and " genera " of Naturalists, of a different order 

 from the disputes of a later time. I think most 



