EVOLUTIONARY THEORIES 99 



systematically they would become ancestors of further lines of 

 evolution, now definitely organic. 



This attitude was also adopted by H. Blum^^ in his interest- 

 ing book Time's arrow and evolution (1951), though he also 

 brought up the question of whether or not the primiti\e 

 autocatalytic molecules should be regarded as living. 



In a recently published article H. J. Muller^^ again affirms 

 his earlier hypothesis, which we have already discussed, as 

 to the random emergence of one successful gene among 

 myriads of types of molecules. 



It is, however, difficult to accept an idea of this kind, in 

 the first place because it completely shuts the door on the 

 scientific study of the most important event in the history 

 of our planet, which was the first emergence of organisms. 

 How can one study a phenomenon which, at best, can only 

 have occurred once in the whole lifetime of the Earth? 



Physicists assert, in principle, that it is possible that the 

 table on which I am WTiting might rise into the air as the 

 result of the chance parallel orientation of the thermal 

 motion of all its molecules. It is, however, hardly likely that 

 anyone will allow for this possibility in his experimental 

 work or general practical activities. 



A theory is of special value to the scientist if it opens up 

 practical possibilities for research by verifying the regular 

 occurrence of phenomena, either by observing nature or by 

 setting up suitable experiments in the laboratory. The con- 

 ception of the chance development of living molecules is 

 quite unproducti\ e practically. 



In contradistinction to this, the evolutionary approach to 

 the problem of the origin of life opens up to the scientist 

 wide possibilities for the study and experimental reproduc- 

 tion of the separate stages of the long course of development 

 of matter which led up to the first appearance of living things 

 on the Earth. 



During the last few years the evolutionary approach to 

 the solution of the problem in which w^e are interested has 

 attracted the minds of wider and wider circles of scientists 

 throughout the world. It is expressed in the flow of books 

 and papers, scientific reviews and experimental researches 



