THE CEREBRUM, AND ITS FUNCTIONS. 759 



we acquire a language. A certain sound conies to be connected in the mind of 

 the child with a certain object, its knowledge of which is derived through the 

 visual or other sense ; and by the habitual recurrence of this connection, the 

 sensational consciousness of the sound comes to suggest the idea of the object, 

 so that the notion of bread or of water is at once called up by the mention of 

 their names ; whilst, on the other hand, the idea of the object reproduces that 

 sensational consciousness of the sound of its name, which is the necessary guide 

 in the pronunciation of the word. And the adult, in learning a new language, 

 goes through a process of a very similar kind; the association being first formed 

 between its words and the words of the language already familiar to him, and 

 the former at last directly suggesting the corresponding ideas, without any 

 necessity for the intermediate process of translation. On the other hand, the 

 sight or the sound of the words of a language altogether unknown to us, excites 

 no other respondent idea in our minds ^than that which arises out of the simple 

 act of perception; namely, the externality of the object which has impressed 

 our sense of vision or of hearing. But the case is different with regard to those 

 signs which are the natural expressions of ideas ] for, in so far as they are so, 

 they intuitively suggest those ideas to the mind of another. This, however, is 

 much more noticeable with regard to the signs of emotional states which are 

 very early interpreted by children, and also by the lower animals than with 

 respect to those which express simple ideas. 1 



791. We have seen that, for the production of a Sensation, a conscious state 

 of mind is all that is required ; whilst, on the other hand, for the exercise of 

 the Perceptive power, a certain degree of attention is requisite ; or, in other 

 words, the Mind must be directed towards the Sensation. And thus it happens 

 that, owing either to the inactivity of the Cerebrum, or to the complete engross- 

 ment of the mind by some other subject of thought, the sensation may neither 

 be perceived nor remembered, notwithstanding that we have evidence, derived 

 from the respondent movements of the body, that it has been felt. Thus a 

 person in a state of imperfect sleep may start at a loud sound, or may turn 

 away from a light shining on his face ] being conscious of the sensation, and 

 acting automatically upon it, but having no consciousness whatever of the object 

 which gave rise to it. And, in like manner, a person in a state of profound 

 abstraction may perform many automatic movements ( 749), which cannot (so 

 far as we know) be excited except through the medium of sensation ; and yet 

 the exciting sensations are neither perceived by him at the time, nor are they 

 afterwards remembered ; so that, when he is aroused from his reverie, he may 

 be astonished to find himself in circumstances altogether different from those 

 under which he passed into it. Sometimes, however, the sensorial impression 

 may excite a sort of imperfect perception, which is subsequently remembered 

 and completed. For example, the student who does not hear the repeated 

 strokes of the clock when his mind is entirely given up to his object of pursuit, 

 may have a sort of vague consciousness of them if his attention be less completely 

 engrossed by his studies ; and although the sounds may not suggest at the 

 moment any distinct idea of the passage of time, yet, when he subsequently 



1 The deaf and dumb are trained to communicate with each other, not merely by the 

 "finger-language," by which words are alphabetically spelled, but also by the "sign-lan- 

 guage," by which ideas are conveyed through the much more direct medium of single 

 signs. These signs, though partly conventional, are made to conform as nearly as possible 

 to the natural expressions of ideas ; and are usually acquired very quickly by the deaf and 

 dumb, whose want of other modes of utterance forces into activity a mode of expressing 

 their ideas and emotions, which is unnecessary to those who have the command of language, 

 and is consequently but little exerted by them. Young children, however, who associate 

 much with the deaf and dumb, very readily acquire this " sign-language," and will often 

 prefer the continued use of it to the acquirement of spoken language. 



