MODERNBIOLOGY 5x7 



himself to the same criticism; his biological reasoning must thus be regarded 

 as out of date even for his age, and partly also somewhat ingenuous; he 

 argues about evolution and heredity without taking into account the re- 

 sults of contemporary research, he believes in much of the old, childish ani- 

 mal-psychology in the spirit of the earlier Darwinism, and he speculates, 

 like Haeckel, upon the possibility of explaining the origin of the sense- 

 organs by means of the theory of selection. Strangely enough, he also de- 

 fends the teleological explanation of nature, as far as biology is concerned — 

 though as a provisional explanation only, until a true causal explanation 

 is forthcoming. His references to all that teleology has achieved in arousing 

 interest in problems and collecting facts with which to solve them may not 

 be devoid of truth, but he certainly overlooks the confusion it has caused 

 by inducing vitalistic explanations of nature; such, in fact, were revived 

 under the influence of Mach, as we shall see later. Finally, with regard to 

 his monism, it possesses, in spite of his own assurances, more philosophical 

 than scientific interest; the practical scientist should at any rate be allowed 

 to treat things as really existing and the changes that take place in them as 

 having been causally effected. 



Another monistic theory was set up by Richard Avenarius (1843-96), 

 professor of philosophy at Zurich. He, too, elaborated a kind of theory of 

 function, but in contrast to Mach he gives to its elements a material nature. 

 His theory, which suffers from having been presented in very difficult lan- 

 guage, has had less influence than Mach's. 



Natural-philosophical theories of this kind may offer some interest as 

 thought-experiments and besides may have their ideal value, if they give 

 expression to the conception of life of a consummate personality. Exact 

 scientific research, on the other hand, carves out paths of its own, its prog- 

 ress sometimes hindered, sometimes furthered by the different conceptions 

 of the world, according to how they deal with existing facts. Pasteur, for 

 instance, in the controversy over spontaneous generation, undoubtedly de- 

 rived advantage from his Catholic dogmatism as against those who saw in 

 spontaneous generation a "philosophical necessity." And his very example 

 shows, too, how in the long run the practical utility of observations is the 

 most conclusive criterion of their value. Those facts will last which con- 

 tribute, however indirectly, towards extending man's dominion over na- 

 ture, whereas the " theories of life," after surviving for a time, find a haven 

 in the archives of cultural history, provided they are found worthy to be 

 preserved there. 



