SPECULATIONS ON THE ORIGIN OF LIFE 

 AND THE EVOLUTION OF LIVING 

 BEINGS 1 



By E. A. MINCHIN, F.R.S. 



Any statements that can be made concerning the Origin of Life 

 must be, at the present time, of a purely speculative nature — 

 a speculation being defined as the logical process of drawing 

 from established data certain conclusions which cannot be 

 directly verified. Though the degree in which a speculation 

 approximates to the truth and commands our confidence in any 

 given case will depend entirely upon the nature of the evidence 

 by which it is supported, a proposition which cannot be directly 

 verified may nevertheless be based on evidence so strong that 

 it receives unhesitating assent from those who are able to 

 understand the premises and follow the reasoning. At the 

 opposite pole to such conclusions are those which cannot be 

 either proved or disproved and are therefore valueless ; as if, 

 for instance, one should attempt to discuss the configuration 

 of the other side of the moon or the nature of the inhabitants 

 of Mars. An intermediate class of speculative thought com- 

 prises discussions that are based upon a large body of established 

 facts though no two authorities may agree completely in interpret- 

 ing the facts : in such cases the conclusions drawn are neverthe- 

 less useful and are an aid to the advancement of science as they 

 serve to draw attention to points in which our knowledge is 

 weak or to indicate important lines of investigation which have 

 been neglected ; as an instance of such speculations, I may 

 cite the much-discussed question of the origin and ancestry of 

 vertebrates, a problem that may be discussed with profit though 

 it may never receive a solution which will command universal 

 assent. 



1 Delivered as the Opening Address in a discussion on the Origin of Life, at 

 a joint meeting of the Botanical and Zoological Sections of the British Association, 

 Dundee, September 10, 1912. 



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