144 THE ANATOMY OF SCIENCE 



dents of daily life give us quite a different view. 

 As I remarked before, nothing is more ludicrous 

 than a moving picture run backward, and this 

 illustrates the extreme dissymmetry of past and 

 future in actual life, which is full of abrupt 

 occurrences in which complex structures, pa- 

 tiently evolved, meet with instant dissolution. 

 A forest burns; a shell explodes, and of all its 

 elaborately prepared chemicals and its intricate 

 machinery only formless fragments remain; a 

 man dies and thus brings to an abrupt end a 

 development which has been proceeding, not 

 merely through a lifetime, but through the 

 ages. 



Here are phenomena so entirely unlike the 

 simple reversible processes we have considered 

 hitherto that we are tempted to believe that our 

 idea of unidirectional time is due to the exist- 

 ence of irreversible phenomena. This thought 

 was, I believe, first expressed by Professor 

 W. S. Franklin,^ and it is one which immedi- 

 ately gives us a deeper insight into the meaning 

 of time. It leads us to split the time-concept into 

 two quite distinct ideas, as Bergson* has done in 



3 W. S. Franklin, "Entropy and Time," Physical Review, 

 SO, 776 (1910). 



4 Bergson, Time and Free Will; Creative Evolution. 



