Life: Its Nature 



and Origin 



Life did originate on this planet some two or more 

 billion years ago but exactly how we do not know. 

 Two avenues of investigation, however, are begin- 

 ning to provide tangible clues as to its probable mode 

 of origin. One consists of an increasingly more 

 detailed knowledge of the structure, chemistry, and 

 physics of life, and the other consists of a better ap- 

 praisal of the possible and probable course of chemi- 

 cal and physical reactions which would have taken 

 place under conditions existing on the pre-biological 

 earth. When these two avenues meet, a plausible 

 and relatively complete hypothesis should emerge 

 to explain how life began on the earth. 



THE NATURE OF LIFE 



As more has been learned about life, it has been 

 found to be a physico-chemical mechanism com- 



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