388 LOUIS AGASSI Z. 



when the sight of the date fills me with con- 

 fusion. And yet, for years, I have not re- 

 ceived a letter which has given me greater 

 pleasure or moved me more deeply. I have 

 felt in it and have received from it that vigor 

 of conviction which gives to all you say or 

 write a virile energy, captivating alike to the 

 listener or the reader. Like you, I am pained 

 by the progress of certain tendencies in the 

 domain of the natural sciences ; it is not only 

 the arid character of this philosophy of nature 

 (and by this I mean, not natural philosophy, 

 but the " Natur-philosophie " of the Germans 

 and French) which alarms me. I dread quite 

 as much the exaggeration of religious fanati- 

 cism, borrowing fragments from science, im- 

 perfectly or not at all understood, and then 

 making use of them to prescribe to scientific 

 men what they are allowed to see or to find 

 in Nature. Between these two extremes it is 

 difficult to follow a safe road. The reason 

 is, perhaps, that the domain of facts has not 

 yet received a sufficiently general recognition, 

 while traditional beliefs still have too much 

 influence upon the study of the sciences. 



Wishing to review such ideas as I had 

 formed upon these questions, I gave a public 

 course this winter upon the plan of creation 



