REASON. 323 



cat and which was the dog, he was ashamed to ask; but 

 catching the cat (which he knew by feeling) he was observed 

 to k)ok at her steadfastly, and then setting her down said, 

 * So puss ! I shall know you another time.' . . . We thought 

 he soon knew what pictures were which were showed to him, 

 but we found afterwards we were mistaken ; for about two 

 months after he was couched, he discovered at once they 

 represented solid bodies, when to that time he considered 

 them as only party-coloured planes, or surfaces diversified 

 with variety of paints ; but even then he was no less sur- 

 prised, expecting the pictures would feel like the things they 

 represented ; and was amazed when he found those parts, 

 which by their light and shadow appeared round and uneven, 

 felt only flat like the rest ; and asked which was the lying 

 sense, feeling or seeing." 



Dr. W. B. Carpenter gives a somewhat similar case which 

 fell within his own observation;* but taking the above as 

 sufficient for our purposes, it is evident that the youth, upon 

 being first able to see, was not able to supply any of those 

 mental inferences from his visual perceptions which alone 

 could make these sensations of any practical use as guides or 

 stimuli to action : that is to say, in the absence of these 

 inferences, these perceptions were imperfect. But he imme- 

 diately set about establishing consciously, or with deliberate 

 intention, those numberless associations between sight and 

 touch which are usually acquired in early infancy, and which 

 are required to constitute the data of the mental inferences 

 which we are considering. The number of such special asso- 

 ciations required being so great and varied, we may wonder 

 that even within the space of three months he should have 

 been able to have made so much progress as to feel his visual 

 perception deceived by the arts of shading and perspective ; 

 but on this point I shall have more to say presently. Mean- 

 while it is enough to remember that the case proves the 

 utility of all our visual perceptions to depend upon the ingre- 

 dient of mental inference which is supplied by liabitual 

 association ; and, of course, we cannot doubt that the same is 

 true of perceptions yielded by the other senses.! 



* Human Physiology, 7tli ed., p. 103, and in more detail, Contemp. Rev., 

 vol. xxi, pp. 781-2. 



t As Adam Smitli observes, in his comments upon this case, " When the 

 young gentleman said that objects which he saw touched his eyes, he cer- 



X 2 



