

Introductory. 13 



as to its method. In other words, not until I shall 

 have fully considered the evidence of organic evolu- 

 tion as a process which somehow or another has 

 taken place, will I proceed to consider how it has 

 taken place, or the causes which Darwin and others 

 have suggested as having probably been concerned in 

 this process. 



Confining, then, our attention in the first instance 

 to a proof of evolution considered as a fact, without 

 any reference at all to its method, let us begin by 

 considering the antecedent standing of the matter. 



First of all we must clearly recognise that there are 

 only two hypotheses in the field whereby it is possible 

 so much as to suggest an explanation of the origin of 

 species. Either all the species of plants and animals 

 must have been supernaturally created, or else they 

 must have been naturally evolved. There is no third 

 hypothesis possible ; for no one can rationally suggest 

 that species have been eternal. 



Next, be it observed, that the theory of a continuous 

 transmutation of species is not logically bound to 

 furnish a full explanation of all the natural causes 

 which it may suppose to have been at work. The 

 radical distinction between the two theories consists 

 in the one assuming an immediate action of some 

 supernatural or inscrutable cause, while the other 

 assumes the immediate action of natural and there- 

 fore of possibly discoverable causes. But in order 

 to sustain this latter assumption, the theory of descent 

 is under no logical necessity to furnish a full proof of 

 all the natural causes which may have been concerned 

 in working out the observed results. We do not 



