10 ADAPTATION AND DISEASE 



the fight, but, once in, confess that I enjoyed the oppor- 

 tunity of measuring my lance against so doughty a knight. 

 The discussion arose over a statement by the Fellow in 

 question that the biologists of to-day had much to learn by 

 turning their attention to the results being gained in medical 

 laboratories. And, sure enough, after protesting with not a 

 little vigour that the boot was on the other foot — that we medical 

 men in our ignorance of biological progress were rediscovering 

 and regarding as our own what had been gained by zoologists 

 and botanists a generation or so previously — Sir Ray Lankester 

 proceeded to justify absolutely my friend's original contention 

 by urging that one fallacy in all Lamarckian doctrine 1 is that 

 adopted by Herbert Spencer, namely, what he called " direct 

 adaptation." There is really, he laid down, no such thing. 

 The supposed mysterious, and as it were miraculous, property 

 of direct adaptation is always due to survival by selection of 

 organisms which varied in many directions — the production of 

 corneous epithelium, of increased hairiness, etc., being favourable 

 variations, which hence have become inherent in tissues of all 

 animals. 2 



1 I confess that I do not like being dubbed a Lamarckian, and that because, 

 as commonly accepted, Lamarckianism is supposed to deal purely with the 

 direct acquirement of alteration in structure through use and environment, 

 and Herbert Spencer, by using the term " direct equilibration," is largely 

 responsible for this vulgar error. The phenomena we pathologists deal with 

 present modification of structure merely as a secondary change : our pheno- 

 mena underlie structural alteration. But in justice to Lamarck it deserves 

 note that he expressly lays down " whatever the environment may do, it does 

 not work any direct modification in the shape and organization of animals. 

 But great alterations in the environment of animals lead to great alterations in 

 their needs, and these alterations in their needs necessarily lead to others in 

 their activities. Now if the needs become permanent, the animals then adopt 

 new habits, which last as long as the needs that evoked them " — and it is the new 

 habits, he points out, which induce the structural alteration. (I quote from 

 Hugh Elliot's excellent translation of the Philosophie zoologique — Lamarck, 

 Zoological Philosophy, Macmillan, 1914, cap. 7.) Granting this, I hold that the 

 physicochemical explanation which will be put forward in the course of these 

 lectures is something more precise and more limited in its scope than the 

 " habits " of Lamarck. 



2 As Sir Ray Lankester has accused me of garbling his statement (see 

 Appendix II.), and has not seen fit to withdraw the charge, I have no hesitation 

 in quoting his exact words : " One fallacy in all Lamarckian doctrine is that 

 adopted by H. Spencer, viz. what he called ' direct adaptation.' There is 

 really no such thing. The supposed mysterious, as it were miraculous, property 

 of direct adaptation is always due to survival by selection of organisms which 

 varied in many directions — the production of corneous epithelium, of increased 

 hairiness, etc., being favourable variations, and hence have become inherent in 

 tissues of all animals. But no more ! " 



