INTR OD UCTION 



when we try to know this principle, action or force, 

 what it is, we find it is beyond our comprehension. 

 The phenomena are co-related ; each involves the co- 

 existence of other phenomena that precede or follow 

 it. Their connection and their sequence are learned, 

 but sooner or later we are led to ultimate causes that 

 are past understanding. This is the case with all 

 we know of the mineral or inorganic world. It is 

 even far more so with the organic world, when we 

 look upon that which has Life. 



The truth of the doctrine of the Evolution of Life, 

 including the Origin of Species, has ceased for years 

 to be a debatable question among men of scientific 

 learning. Though from the nature of its subject it 

 is incapable of mathematical demonstration, yet the 

 facts supporting its truth are so convincing to the 

 mind and so well established that, like Newton's law 

 of gravitation, the theory is now beyond discussion. 

 Like Newton's law, also, this doctrine at first met 

 with violent 'opposition. Each changed and over- 

 threw old, long-established, orthodox beliefs ; for over 

 one hundred years Newton's theory of gravitation 

 was rejected by many ; was considered to be atheistic 

 and impious. From similar reasons, about fifty 

 years ago, intense indignation and excitement was 

 caused by the publication of the " Vestiges of Crea- 

 tion," an imperfect theory of natural evolution. The 



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