186 SOME FINAL CONSIDERATIONS 



centres on this orderliness in biology, whereas physics and 

 chemistry consider only isolated modes of action and are blind 

 to their association in the real process. 



It follows from these considerations that we must divide the 

 question of the relationship between biology, physics and 

 chemistry into two parts. We must consider, on the one hand, 

 the modes of action occurring in living organisms, as such. 

 But, on the other hand, we must take into account their spatial 

 and temporal connections. 



It follows from the above that it is meaningless to ask 

 whether in biology modes of action will at any time be found 

 which for fundamental reasons cannot be reduced to, and ex- 

 plained by, the laws of physics and chemistry. For if the 

 biologist, in the course of his analyses of living organisms, 

 encounters modes of action that are not yet known to, or 

 analysed by, the physicist or chemist, it will be the task of the 

 latter to study these phenomena with their own methods, i.e. 

 by complete isolation, and to trace the laws on which they are 

 founded. This is not just a hypothetical case, as may be seen 

 from the number of times that physics and chemistry have 

 already borrowed their problems from biology. A well known 

 example is the importance of the role played in the development 

 of the theory of electricity byGalvani's observation that exposed 

 frog muscles twitch if they touch two different metal con- 

 ductors. In a later period, physical chemistry received an 

 important impetus from Pfeffer's observations on osmotic 

 phenomena in plant cells, which led to a closer analysis by 

 physicists and chemists of the laws on which these phenomena 

 are founded. It might be said, in general, that the sciences of 

 "here" and "now" (to which belong, apart from biology, such 

 other branches of science as geology, physical geography, 

 meteorology, and astronomy), supply the material that is 

 studied more closely by physics and chemistry. These latter 

 disciplines unravel this material into its elementary components, 

 in order to derive the natural laws that are valid for the whole 

 of the reality of nature. Once we have understood this, we see 

 that the assumption is unfounded that biology may some time 

 detect modes of action which, for fundamental reasons, do 



