154 ARE THE EFFECTS OF USE INHERITED? 



and manner of action on co-operative parts, and 

 by adapting these parts to the total amount of 

 nourishment received rather than to occasional 

 necessity or actual usefulness. It would tend to 

 stereotype habits and convert reason into instinct. 



How then can we rely upon use-inheritance for 

 the improvement of the race ? Even if it is not a 

 sheer delusion, it may be more detrimental as a posi- 

 tive evil than it is advantageous as an unnecessary 

 benefit ; and as a normal modifying agent it is 

 miserably weak and untrustworthy in comparison 

 with the powerful selective influences by which 

 nature and society continually and inevitably affect 

 the species for good or for evil. The effects of use 

 and disuse rightly directed by education in its 

 widest sense must of course be called in to secure 

 the highly essential but nevertheless superficial, 

 limited, and partly deceptive improvement of indi- 

 viduals and of social manners and methods ; but as 

 this artificial development of already existing 



