220 THE HUMAN BODY 



perceive it. What we really feel is, however, the change produced 

 by it in our eyes. There are no parts of our Bodies reaching to 

 a tree or a house a mile off and yet we seem to feel all the while 

 that we are looking at the tree or the house and feeling them, and 

 not merely experiencing modifications of our own eyes or brains. 

 When reading we feel that what we really see is the book; and yet 

 the existence of the book is a judgment founded on a state of our 

 Body, which alone is what we truly feel. 



We have the same experience in other cases, for example with 

 regard to touch. 



Hairs are quite insensible, but are embedded in the sensitive 

 skin, which is excited when they are moved. But if the tip of a 

 hair be touched by some external object we believe we feel the 

 contact at its insensible end, and not in the sensitive skin at its 

 root. So, the hard parts of the teeth are insensible; yet when we 

 rub them together we refer the seat of the sensation aroused to the 

 points where they touch one another, and not to the sensitive parts 

 around the sockets where the sensory nerve impulse is really 

 started. 



Still more, we may refer tactile sensations, not merely to the 

 distal ends of insensible bodies implanted in the skin, but to the 

 far ends of things which are not parts of our Bodies at all; for 

 instance, the distant end of a rod held between the finger and a 

 table while the finger is moved a little from side to side. We then 

 believe we feel touch or pressure in two places; one where the rod 

 touches our finger, and the other where it comes in contact with 

 the table. A blind man gropes his way along by feeling at the end 

 of his stick. 



This irresistible mental tendency to refer certain of our states 

 of feeling to causes outside of our Bodies, whether in contact with 

 them or separated from them by a certain space, is known as the 

 phenomenon of the extrinsic reference of our sensations. It seems 

 largely to depend on the fact that the sensations extrinsically 

 referred can be modified by movements of our Bodies. Hunger, 

 thirst, and toothache all remain the same whether we turn to the 

 right or left, or move away from the place we are standing in. 

 But a sound is altered. We may find that in a certain position 

 of the head it is heard more by the right ear than the left ; but on 

 turning round the reverse is the case; and halfway round the 



