12 The Living Plant 



if for no other reason than this, — that the language one may use 

 is concerned. My position in general is the Darwinian one, — 

 that adaptation in the main has arisen as a gradual causative 

 accompanhnent of evolution. Indeed, such a causative, or histor- 

 ical development of adaptation appears to me an inseparable 

 corollary of the very idea of evolution, and wholly independent 

 of its method, — whether it proceed by many imperceptibly small 

 steps as Darwin beheved, or by fewer and perceptible ones, as 

 newer evidence seems to be showing. And the point about use 

 of language is this, that if adaptation is a causative process, — 

 the feature developing in causal touch with the conditions con- 

 cerned, — then it is quite suitable and correct to say that the adap- 

 tation exists for such-and-such a purpose; and I do not hesitate to 

 use such expressions in this book. In so doing I am in the very 

 best of company, for Darwdn himself continually uses the language 

 of purpose, or teleology; and both Huxley and Asa Gray, Darwin's 

 devoted friends and co-believers, point out in their writings that 

 evolution on the basis of Natural Selection places teleology on a 

 scientific basis.* This fact is overlooked in our day by many, 

 who think it scientific to avoid teleological or purposeful language 

 as though it were a plague. Science, indeed, hath her fashions 

 and her dogmas no less than other fields of human endeavor. 



A chief reason for the occasional denials of the causative origin 

 of adaptation arises from reaction against the over-importance, 

 and over-perfection, so often attributed to it. Adaptation has 

 often been clamied on the scantiest evidence without any attempt 

 at proof. At its best, however, adaptation can never be perfect, 

 but is rather a general or generic affair, very much hke our own 

 adaptations to the trades or professions we follow. This is be- 

 cause no feature of structure or function is free to respond to one 

 adaptive need alone, but has to compromise with other consider- 



* An example of Darwin's teleological language is found in the passage from one 

 of his books cited on page 234 of this volume. As to his establishment of teleology 

 as a scientific principle, compare his Life and Letters, New York, 1888, 11, 430. 



