76 A SCIENTIFIC APPROACH 



half of the nineteenth century that they overrode the prin- 

 ciple of evolution in relation to the problem of the origin 

 of life, although a great deal of preparatory work had already 

 been carried out along evolutionary lines. 



The mechanistic conception of life and its origin prevalent 

 in those times was fundamentally this: there is no essential 

 difference between organisms and inorganic bodies. Living 

 things are merely special forms of machines having an 

 exceptionally complicated structure of integrated material 

 particles. Just as the specific function of a machine is deter- 

 mined by the particular circumstances and arrangements of 

 its parts, so the life of an organism depends on the finest 

 details of its internal structure, on the proper interrelation 

 between the atoms and molecules in living protoplasm. 

 From this it follows that the emergence of life is not the 

 emergence of something qualitatively new. The whole ques- 

 tion simply comes to this: how did the combinations of 

 material particles characteristic of life arise and how did 

 the peculiar structure of all living things arise? 



In the inorganic world we are constantly observing the 

 formation of structures built in an orderly way under the 

 action of definite physical forces ; crystals develop from 

 molecules or ions scattered at random throughout the solu- 

 tion. According to the mechanists the problem of the origin 

 of living things is, in the last analysis, nothing but the problem 

 of the crystallisation of organic matter. Thus the primary 

 origin of life seems to be a logically inevitable deduction 

 from the theory already propounded. 



In practice, however, the facts prove to be in direct contra- 

 diction to this hypothesis. Nowhere in nature do we observe 

 the primary origin of life and all our attempts to reproduce 

 this phenomenon under artificial conditions have been fruit- 

 less. 



The only way which the mechanistically minded scientists 

 of those times could see out of the blind alley which they 

 had thus created was to suppose that the conditions for the 

 formation of living structures, ' the crystallisation of living 

 matter ', were so complicated and specific that this crystallisa- 

 tion could only take place in the remote past and is now 

 impossible because the physical or chemical conditions on 



