1878 LBCTUEE ON ANIMAL INTELLIGENCE 75 



eminently successful. You have indeed passed a 

 most magnificent eulogium on me, and I wonder 

 that you were not afraid of hearing ' Oh ! oh ! ' or 

 some other sign of disapprobation. Many persons 

 think that what I have done in science has been 

 much overrated, and I very often think so myself ; 

 but my comfort is that I have never consciously done 

 anything to gain applause. Enough and too much 

 about my dear self. The sole fault that I find with 

 your lecture is that it is too short, and this is a rare 

 fault. It strikes me as admirably clear and interest- 

 ing. I meant to have remonstrated that you had 

 not discussed sufl&ciently the necessity of signs for 

 the formation of abstract ideas of any complexity, 

 and then I came on to the discussion on deaf mutes. 

 This latter seems to me one of the richest of all the 

 mines, and is worth working carefully for years and 

 very deeply. I should like to read whole chapters 

 on this one head, and others on the minds of the 

 higher idiots. Nothing can be better, as it seems to 

 me, than your several lines or sources of evidence, 

 and the manner in which you have arranged the 

 whole subject. Your book will assuredly be worth 

 years of hard labour, and stick to your subject. By 

 the way, I was pleased at your discussing the selec- 

 tion of varying instincts or mental tendencies, for I 

 have often been disappointed by no one ever having 

 noticed this notion. 



I have just finished La Psychologie, son prisent 

 et son avenir, 1876, by Delbceuf (a mathematician 

 and physicist of Belgium), in about one hundred 

 pages ; it has interested me a good deal, but why I 



