8 INTRODUCTION 



them some half-century ago. All the 

 materialistic writers I know of who have tried 

 to bite that file have simply broken their 

 teeth. But if this is true, our one certainty 

 is the existence of the mental world, and that 

 of Kraft und Stoff falls into the rank of, at 

 best, a highly probably hypothesis." 

 With this short introduction I leave the Huxley 

 Lecturers to speak for themselves. 



OLIVER LODGE. 

 March, 1914. 



