ARE ACQUIRED CHARACTERS HEREDITARY? 325 



Misunderstanding III. Begging the question by starting with 

 what is not proved to be a modification. There is no relevancy in citing 

 cases where an abnormal bodily peculiarity re-appears generation 

 after generation, unless it be shown that the peculiarity is a modifica- 

 tion, and not an inborn variation whose transmissibility is admitted 

 by all. Short-sightedness may recur in a family-series generation 

 after generation, but there is no evidence to prove that the original 

 short-sightedness was a modification. In all probability, short- 

 sightedness is in its origin a germinal variation, like so many other 

 bodily idiosyncrasies. 



In regard to some diseases, such as rheumatism, it is often said 

 dogmatically by those who know little about the matter that the 

 original affection in the ancestor was brought about by some definite 

 external influence such as a cold drive or a damp bed; but it seems 

 practically certain that in all such cases we have to do with an inborn 

 predisposition, to the expression of which the cold drive or the damp 

 bed were merely the liberating stimulus, comparable to the pulling of 

 the trigger in a loaded gun. The liberating stimulus is, of course, of 

 great importance, both in the case of the gun's discharge and the 

 organism's disease, but it only goes a little way towards a satisfactory 

 interpretation in either case. Not that we can explain the origin of 

 rheumatism or shortsightedness or any such thing there is no expla- 

 nation in calling them germinal variations that cropped up; but we 

 are almost certain that they never are modifications or acquired 

 characters. 



Herbert Spencer twits those who are sceptical as to the trans- 

 mission of acquired modifications with assigning the most flimsy 

 reasons for rejecting a conclusion they are averse to; but when Spencer 

 cites the prevalence of short-sightedness among the "notoriously 

 studious" Germans, the inheritance of a musical talent, and the inheri- 

 tance of a liability to consumption, as evidence of the inheritance of 

 modifications, we are reminded of the pot calling the kettle black. 



Over and over again in the prolific literature of this discussion the 

 syllogism is advanced, either in regard to gout or something analogous- 

 Gout is a modification of the body, an acquired character; 



Gout is transmissible; 



Modifications are sometimes transmissible. 



It may be formally a good argument, but there is every reason to 

 deny the major premise. There is no proof that the gouty habit had 

 an exogenous origin that it was, to begin with, for instance, the 

 direct result of high living; though it is generally admitted that 



