16 ANIMAL INTELLIGENCE 



viduals are concerned, are possibly beyond solution. 

 Such are probably few in number, and under attack by 

 new methods may be rendered still fewer ; nevertheless, 

 it is healthful for man to say now and then after the 

 fullest study " I do not know." There are states of 

 our minds which no doubt bear a closer approximation 

 to those of animals than others, and these should be 

 seized upon and analysed, if we would understand the 

 mental life of animals. No small part of our psychic 

 life differs from that of animals rather in degree than 

 in kind. Nothing is to be gained for any cause, how- 

 ever, by overstating the case, and it is a mistake to 

 claim that between the highest men and the most 

 intelligent animals there is not a vast difference, even 

 if we do not go so far as to say there is a great gulf 

 fixed, as some appear to believe. This is another thing, 

 however, from assuming that the same holds for the 

 most lowly developed men and the most highly 

 developed animals. As to the differences in the latter 

 case, there is room for great diversity of opinion in the 

 present state of our knowledge. 



Experiments with the lowest classes of men and on 

 all kinds of animals are urgently needed. 



In the meantime a modest, enquiring, open state of 

 mind is that most becoming and helpful. 



