210 Darwinism and Other Essays. 



this strangely beautiful scene we enter upon quite 

 a Platonic dialogue, in which the author seeks to 

 expound his new conception of causation, while 

 Mr. Buckle occasionally interposes with "I do 

 not follow you, I confess," or " That seems philo- 

 sophical enough," quite after the manner of the 

 <f>aivfTai or OVK l/ioiye Soxei of Sokrates and his in- 

 terlocutors. This long conversation, or series of 

 conversations, is perhaps the most interesting por- 

 tion of the book. Yet Mr. Buckle evidently does 

 not get a thorough hold of what Mr. Stuart-Glen- 

 nie means by defining causation as involving "not 

 merely the conception of Uniformity of Sequence," 

 but also that of "Mutuality of Coexistence, or 

 Mutual Determination ; " and we must confess 

 that to us also his meaning seems by no means 

 distinctly set forth or adequately elucidated. It is 

 to be hoped that in future volumes this point will 

 be thoroughly cleared up, for we are told that the 

 "Change in our conceptions of the Causes of 

 Change," which the author has discovered to be 

 the " Ultimate Law of History," is neither more 

 nor less than " an advance from the conception of 

 One-sided Determination to that of Mutual De- 

 termination." That this statement is fraught 

 with meaning for Mr. Stuart -Glennie there can 

 be no doubt ; he recurs to it again and again, as if 



