2o6 ORIGINAL SIN 



Among these facts the ones which are most open to 

 general observation are connected with the hereditary 

 nature of certain diseases, such as tuberculosis and 

 syphihs. Dr. Brown-Sequard performed some notable 

 experiments upon guinea-pigs which seem to prove 

 that an artificially induced epilepsy can be transmitted.^ 

 There seems to be something desperate in Professor 

 Weismann's comment on these experiments when he 

 says, "Clearly formulated problems, Uke that of the 

 inheritance of acquired characters, should not be con- 

 fused by bringing into them phenomena whose causes 

 are quite unknown. What do we know of the real 

 causes of those central brain irritations which give 

 rise to the phenomena of epilepsy ? It is certain enough 

 that there are diseases which are acquired and yet 

 are 'inherited,' but that has nothing to do with the 

 Lamarckian principle, because it is a question of in- 

 fection of the germ, not of a definite variation in the 

 constitution of the germ." ^ What does such a reply 

 amount to? The question at issue is not whether the 

 effect of disease on the germ is to be called ''infection," 

 instead of a "definite variation," nor whether we know 

 the real causes of the irritations which produce epilepsy. 

 The question is. Are acquired diseases inherited? He 

 confesses that in certain instances they are, and thus 

 concedes the real point at issue; for no one now main- 



ments in behalf of the Lamarckian view are summarized by R. H. 

 Lock, Recent Progress, pp. 59-65. 



^ Described by V. L. Kellogg, op. cii., pp. 290-295. 



2 Evolution Theory, Vol. II. p. 68. 



