SOME "FINAL CONSIDERATIONS 185 



the conclusion on the nature of life to which this leads. We 

 may start from the considerations developed by H. J. Jordan 

 (1941, and elsewhere). 



In Jordan's opinion, the difference between physics and 

 chemistry, on the one hand, and biology, on the other, is a 

 difference in method rather than a difference in subject. It is 

 not really correct to oppose physics and chemistry, as the 

 sciences of lifeless nature, to biology, as that of living nature. 

 Physics and chemistry are sciences of the whole of nature, both 

 living and lifeless. Their task is the study of the modes of 

 operation occurring in nature. Therefore, being analytic and 

 experimental sciences, they attempt as far as possible to 

 isolate the factors acting on one another. They attempt to 

 become independent of the fortuitous circumstances of the ex- 

 periment by eliminating, one after the other, all those factors 

 which interfere with the analysis of the phenomenon that is 

 being studied. In this way, physics and chemistry arrive at 

 formulations of "laws of nature", which are expressions of the 

 modes of operation encountered. These sciences are not in- 

 terested in the fact that the circumstances postulated in these 

 "laws" do not "occur" in nature in this form, so that no falling 

 object behaves entirely according to the simple law of gravita- 

 tion, and no billiard ball is so perfect that it does not show 

 deviations from the basic laws of collision. What is more, they 

 are scarcely, if at all interested in the actual occurrence^ the 

 "here and now" of the phenomena. Physics studies the properties 

 of electrical discharges, but does not ask where the lightning 

 strikes. Chemistry states that A reacts with B if the two meet, 

 but it is not interested in knowing whether or not the two ever 

 do meet in nature without the mediation of the investigator, 

 and whether this occurs often or rarely. 



In biology, the situation is entirely different. Here all in- 

 terest is focused on the "here'' and "now'\ It is not the fact 

 that A reacts with B which is the most important thing in 

 biology, but that this reaction takes place exactly here, and at 

 just this moment. All phenomena in living organisms have their 

 fixed place and time of occurrence; only by virtue of this fact 

 is the orderly progress of living phenomena possible. Interest 



