RELATION OF TONE AND GESTURE TO WORDS. 1 53 



Thus all the evidence at our disposal goes to show that, 

 while the language of tone and gesture is distinctive, in its 

 least-developed form, of a comparatively low grade of mental 

 evolution, in all but its least-developed form it is not thus 

 distinctive ; for as soon as the language of gesture becomes in 

 the smallest degree conventional, so soon is the psychological 

 level sufficiently high to admit of the use of articulate sounds, 

 vocal gestures, or words expressive of concrete ideas — always 

 supposing that these are already supplied by the psycho- 

 logical environment. Whether or not articulate sounds are 

 then actually made depends, of course, on conditions of a 

 purely anatomical kind. 



And here it may be as well to remember the point pre- 

 viously mentioned, namely, that although no existing quad- 

 rumanous animal has shown itself able to articulate, we may 

 be quite sure that this fact depends on anatomical as dis- 

 tinguished from psychological conditions ; for not only are 

 the higher monkeys much more intelligent than talking birds, 

 but they are likewise much more imitative of human gestures; 

 and for both these reasons they are the animals which, more 

 than any others, would be psychologically apt to learn the 

 use of words from man, were it not for some accident of 

 anatomy which stands in the way of their uttering them. 

 And in this connection it is worth while to bear in mind the 

 remark of Professor Huxley, that an imperceptibly small 

 difference of innervation, or other anatomical character of the 

 parts concerned, might determine or prevent the faculty of 

 making articulate sounds. 



Looking to the direction in which my argument is tending, 

 this appears to be the most convenient place to dispose of a 



of estimating the reflex influence of speech upon gesture, in the case of the high 

 development attained by the latter in man. In the text I am now considering the 

 converse influence of gesture upon speech, and find that it is no more easy precisely 

 to estimate. There can be no doubt, however, that the reciprocal influence must 

 have been great in both directions, and that it must have proceeded from gesture 

 to speech in the first instance, and afterwards, when the latter had become well 

 developed as a system of auditory signs, from speech to gesture. More will 

 require to be said upon this point in a future chapter. 



