138 Inside the Living Cell 



(5) new inborn tendencies are acquired to indulge in types of play 

 which give the opportunity of developing muscular skills and 

 a close correlation between muscular action and sense im- 

 pressions. 

 This is a rather formidable list of 'improvements'. Their chief effect 

 is to permit the accurate use of tools and the development of 

 language. 



Tools are external objects which are used as extensions of the limbs 

 so as to increase their reach and performance. They are controlled by 

 the brain in exactly the same manner as the limbs themselves. When 

 a violinist plays, the muscles which operate the instrument are con- 

 trolled by means of the information reaching the brain from the 

 sense of touch and hearing. The nervous circle goes from the muscles 

 to the instrument and re-enters the brain through the senses. The 

 accurate use of tools thus depends on using the sense data to control 

 precisely the muscular actions which are producing the movements 

 of the tool. This is obviously not a new faculty, but only a more pre- 

 cise use of abilities similar to those which higher animals possess. 



In a sense the human voice can also be regarded as a tool, which is 

 controlled in exactly similar ways, i.e. I listen to the sound of my 

 voice and modify it according to what I hear. The muscles which pro- 

 duce the voice are thus controlled through the sense of hearing. 



It must have been discovered by early man that he could make 

 sounds which influenced actions and so bring about desired results. 

 Sounds could be produced which were either ingratiating or frighten- 

 ing or merely served as a signal to draw attention to something. 



The voice thus took its place, like the limbs, as a means of bringing 

 about actions. Just as human beings planned their muscular actions 

 within their pictures of the world, so they also produced sounds as 

 part of their reaction to the picture provided by the senses. In such 

 sounds we see the origin of language. Certain sounds became asso- 

 ciated with particular situations and thus acquired a meaning and 

 thus, in time, a 'language' of sounds was built up. From this point of 

 view the important thing about the language is that initially it is a 

 muscular act — a series of useful and effective muscular responses to 

 a given situation. 



From this point of view it can be seen that the organization of 

 language is perhaps a development of an ability which was already 

 present in the animal brain, which already provided a means of org- 

 anizing from the sense picture something of a very different nature, 

 viz. appropriate muscular actions. It is not a very big step from this 

 to the setting up of a mechanism for producing appropriate sounds 

 and associating these sounds with situations. The sounds are very 



