84 LOUIS PASTEUR 



settled, he resolved to devote himself to the task. 

 In January, i860, he wrote to his friend, Chappuis, 

 "I am doing my best with these studies on fermen- 

 tation, which have a great interest on account of 

 their relation to the impenetrable mystery of life 

 and death. I hope to make soon a decisive step by 

 solving, without the least confusion, the celebrated 

 question of spontaneous generation. Already I 

 could speak, but I want to perform still more ex- 

 periments. There is so much passion and so much 

 obscurity on both sides, that it will require nothing 

 less than the cogency of an arithmetical demon- 

 stration to convince my adversaries of my conclu- 

 sions. I intend to accomplish even that." 



Biot, who had followed Pasteur's career, with 

 a sort of fatherly interest, endeavored to dissuade 

 him from an investigation which he believed would 

 prove fruitless. Dumas, less decided in his remon- 

 strance, remarked that he "would counsel no one 

 to occupy himself too long with such a subject." 

 But Pasteur, who doubtless had a clearer vision 

 in this field than either of his elder counselors, per- 

 ceived that the problem of spontaneous generation 

 lay, as it were, across his path. To attack it, was 

 the next logical step in his scientific career. 



The belief in the spontaneous origin of living 



