Intellectual and Moral Faculties 121 



implements will be read with interest; these are similar to the 

 observations on modern eoliths, and their bearing on the develop- 

 ment of the stone-industry. It is interesting to learn from a letter 

 to Hooker 1 , that Darwin himself at first doubted whether the stone 

 implements discovered by Boucher de Perthes were really of the 

 nature of tools. With the relentless candour as to himself which 

 characterised him, he writes four years later in a letter to Lyell in 

 regard to this view of Boucher de Perthes' discoveries: "I know 

 something about his errors, and looked at his book many years ago, 

 and am ashamed to think that I concluded the whole was rubbish ! 

 Yet he has done for man something like what Agassiz did for 

 glaciers 2 ." 



To return to Darwin's further comparisons between the higher 

 mental powers of man and animals. He takes much of the force 

 from the argument that man alone is capable of abstraction and 

 self-consciousness by his own observations on dogs. One of the 

 main differences between man and animals, speech, receives detailed 

 treatment. He points out that various animals (birds, monkeys, 

 dogs) have a large number of different sounds for different emotions, 

 that, further, man produces in common with animals a whole series 

 of inarticulate cries combined with gestures, and that dogs learn to 

 understand whole sentences of human speech. In regard to human 

 language, Darwin expresses a view contrary to that held by Max 

 Miiller 3 : "I cannot doubt that language owes its origin to the 

 imitation and modification of various natural sounds, the voices of 

 other animals, and man's own instinctive cries, aided by signs and 

 gestures." The development of actual language presupposes a 

 higher degree of intelligence than is found in any kind of ape. 

 Darwin remarks on this point 4 : "The fact of the higher apes not 

 using their vocal organs for speech no doubt depends on their 

 intelligence not having been sufficiently advanced." 



The sense of beauty, too, has been alleged to be peculiar to man. 

 In refutation of this assertion Darwin points to the decorative colours 

 of birds, which are used for display. And to the last objection, that 

 man alone has religion, that he alone has a belief in God, it is 

 answered "that numerous races have existed, and still exist, who 

 have no idea of one or more gods, and who have no words in their 

 languages to express such an idea 5 ." 



The result of the investigations recorded in this chapter is to 

 show that, great as the difference in mental powers between man and 



1 Life and Letters, Vol. n. p. 161, June 22, 1859. 



2 Ibid. Vol. in. p. 15, March 17, 1863. 



3 Descent of Man, p. 132. * Ibid. pp. 136, 137. 

 5 Ibid. p. 143. 



