m.] INDUCTIVE PROOF 25 



the fleshy- stemmed Euphorbias and Stapelias 

 of Africa. Similarly Arctic and Antarctic plants 

 are much like those of high Alpine regions. 

 All aquatic plants have certain features in 

 common. Such " parallels " are innumerable. 



What conclusion can be drawn from these 

 universal facts ? It is a perfectly safe induction, 

 based on an immense number of coincidences, 

 that the same causes have produced the same 

 effects under similar conditions. That is, a true 

 natural law is recognisable. 



What, then, is the cause ? There is nothing 

 else than the surrounding conditions under which 

 the plants grow alike. These constituting the 

 environment are the "cause," or supply the 

 " direct or definite action," as Darwin calls it, 

 to which the plants, or we might say, the living 

 protoplasm and its nucleus respond ; and so 

 build up identically the same structural forms. 



This is a perfectly legitimate argument, the 

 coincidencies are innumerable, and occur in all 

 members of the plant world, so that the 

 ecologist says: "We are invincibly forced to 

 see " the direct cause in the environment (M. 

 Costantin). 



Now, it is a most important fact which I 

 would reiterate, that this was exactly Darwin's 

 later view, as an alternative to his theory 

 of natural selection, to which Darwinians per- 

 sistently adhere. I have already quoted Darwin's 



