Nineteenth-Century Science and Religion i 59 



of their mutability. The physical theory, like the mathematical 

 one, appeared to be not something provided with a necessity 

 a priori y but as a free construction of the mind. Several of these 

 constructions can be made. The choice is settled by considera- 

 tions of practical convenience. Hertz says that several repre- 

 sentations are possible, several models of one and the same group 

 of phenomena, and that their value lies in their capacity for 

 pre-vision, that one being chosen v^^hich is most convenient. Our 

 theories, therefore, are merely images or useful symbols. 



7. Neo-vitalism, which, especially as a result of the labours of 

 Driesch, descended from the metaphysical field to the dominion 

 of experimental biology, showed the impossibility of explaining 

 certain facts, such as the phenomena of regeneration, by means of 

 physical and chemical laws. The property which fragments of 

 certain organisms have of regenerating the whole does not permit 

 one to compare the organism to a machine, however complicated. 



8. When the first enthusiasm aroused by mathematical formu- 

 lations of psychic phenomena had disappeared, the discussions 

 concerning the value of the law of Weber and Fechner, and 

 concerning the methods of measuring in experimental psychology, 

 clearly revealed the fact that the conception of measure could not 

 have the same value in this field as in the physical field. Psychic 

 facts are qualitatively different, and therefore cannot be directly 

 measured with regard to each other. The law of the conservation 

 of quantity has no significance in the spiritual life, but is rather a 

 perennial creation of new qualities. Every moment of our interior 

 life has, in its concreteness, its own original physiognomy, which 

 evades all generic schemes of quantitative formulae. (Bergson.) 



6. The Crisis of Scientific Intellectualism : Agnosticism 



Some of the foregoing observations have shown us that there 

 was a profound contradiction in the very bosom of the theory of 

 evolution, which was the pet idea of Positivism. That is to say, 

 they have shown the contrast between the mechanical conception 

 of the world, according to which everything is settled ah aeterno 

 in a changeless system of mathematical relations outside of time, 

 and the historic vision of reality in its concrete development, 

 according to which time has a living efficacy and new forms of 

 existence continually arise which were not contained in the pre- 

 ceding phases. The one is the world of the foreseeable, the other 



