XX INTRODUCTION 



Pasteur died September 28, 1895, and the Council of 

 the Institute elected Duclaux to be his successor. Noth- 

 ing less resembled the dreamy, intuitive nature of Pas- 

 teur, turn by turn combative and silent, than the'modest, 

 passionate, devoted soul of his apostle. They were equal 

 only in a generous ardor of soul and in the patient tenac- 

 ity which both gave to the service of science. Never- 

 theless, it was Duclaux of all the Pasteurians, who 

 possessed most fully the entire tradition of the master, 

 since he had been more or less closely associated with him 

 and familiar with his ideas since 1858. 



Nothing was more natural therefore than that he 

 should write a book on Pasteur. Even before the Insti- 

 tute was thought of, Duclaux wished to erect in his own 

 way another monument to the memory of his master. 

 For he realized how fragile is life and that already many 

 things had ceased to exist except in his memory. There- 

 fore, he wrote this book: "Pasteur: Histoire d'un Esprit." 

 In it the Pasteurian discoveries unfold in their harmo- 

 nious development with, perhaps, a little more amplitude 

 and coherence, a little less originality and vivid pro- 

 fundity than in the reality. He who has read this book 

 will understand the reach of the greatest scientific move- 

 ment in the nineteenth century, and at the same time will 

 appreciate how slowly the truth unfolds and how often 

 genius itself loses the thread of the labyrinth in traversing 

 it for the first time. Now that we have made of this 

 daedalus one of the boulevards of the modern mind, it 

 is good to recall what obstacles and what errors then 

 rendered it almost impracticable. The one who knew 

 best the founder of microbiology has written of the book 

 as follows: "After having read this analysis of his work, 

 we understand Pasteur better, and find him greater still" 

 (Dr. Roux). We understand better both Pasteur and 

 Duclaux. Pasteur followed his idea as the magi their 



