THE WORK OF PASTEUR 33 



teenth century misses fire, it misses fire on the question of the 

 origin of life. 



Thus idealism, which, as we have already seen, argued 

 obstinately throughout its whole history in favour of the 

 existence of spontaneous generation, carried out a complete 

 volte face on this question at the beginning of the present 

 century. The triumph of the theory of evolution forced the 

 vitalists to regard the problem of the origin of life as the 

 last refuge of the ' life force '. Darwinism might well give 

 a materialist explanation of the ways in which higher organ- 

 isms develop from lower ones, but the human mind would 

 never be able to understand how life itself came about, 

 because its essence (' entelechy ', the ' life force ', the ' cellular 

 spirit ', etc.) lay at the limit of the capacity of the intellect. 

 We find this in the WTitings of most of the neovitalists and 

 other idealistically inclined biologists of our century. Thus 

 H. Driesch^^ wrote of the insolubility of the problem of the 

 origin of this vital principle which he called ' entelechy '. 

 Uexkiill" drew attention to the necessity for a special trans- 

 cendental factor (structural plan) for the origin of life. L. 

 Bertalanffy^* denied the possibility of the self-formation of 

 such a system as, in his opinion, an organism must be. E. 

 Lippmann finishes his book^ devoted to the problem of the 

 emergence of life with the words: "The limitations of the 

 intellect prevent us from penetrating into the problem of 

 life. . . . We cannot understand its essence which appears to 

 be metaphysical." Thus the idealists try to use the demoli- 

 tion of the theory of spontaneous generation as an occasion 

 for proclaiming the impossibility of solving the question of 

 the origin of life on a materialistic basis. 



The leading proponents of materialism rejected this ap- 

 proach to the problem right from its inception in the last 

 years of the nineteenth century. They considered that the 

 fact that microbes do not develop spontaneously in organic 

 solutions and infusions was no argument that life has not a 

 material origin. 



One of the first to discuss this problem was F. Engels.^" 

 He remarked that all investigations so far made in this field 

 had been quite limited in approach, dealing only with the 



