THE FACTS OF SCIENCE 6i 



speak of individual objects having an existence independ- 

 ent of our own. The store of past sense-impressions, our 

 thoughts and memories, although most probably they 

 have beside their psychical element a close correspondence 

 with some physical change or impress in the brain, are yet 

 spoken of as mside ourselves. On the other hand, although 

 if a sensory nerve be divided anywhere short of the brain 

 we lose the corresponding class of sense-impression, we yet 

 speak of many sense-impressions, such as form and texture, 

 as existing outside ourselves ? How close then can we 

 actually get to this supposed world outside ourselves ? Just 

 as near as but no nearer than the brain terminals of the 

 sensory nerves. We are like the clerk in the central tele- 

 phone exchange who cannot get nearer to his customers 

 than his end of the telephone wires. We are indeed worse 

 off than the clerk, for to carry out the analogy properly we 

 must suppose him never to have been outside the telephone 

 exchange, never to have seen a customer or any one like a 

 customer — in short, never, except through the telephone wire, 

 to have come in contact with the outside imivcrse. Of that 

 •" real" universe outside himself he would be able to form no 

 direct impression ; the real universe for him would be the 

 aggregate of his constructs from the messages which were 

 caused by the telephone wires in his office. About those 

 messages and the ideas raised in his mind by them he might 

 reason and draw his inferences ; and his conclusions would 

 be correct — for what? For the world of telephonic messages, 

 for the type of messages which go through the telephone. 

 Something definite and valuable he might know with 

 regard to the spheres of action and of thought of his 

 telephonic subscribers, but outside those spheres he could 

 have no experience. Pent up in his office he could never 

 have seen or touched even a telephonic subscriber iii him- 

 self. Very much in the position of such a telephone 

 clerk is the conscious ego of each one of us seated at the 

 brain terminals of the sensory nerves. Not a step nearer 

 than those terminals can the ego get to the " outer world," 

 and what in and for themselves are the subscribers to its 

 nerve exchange it has no means of ascertaining. Messages 



