THE PERCEPTION OF SPACE. 181 



It will have been noticed iu the account given that 

 when tivo sensorial space-impressions, believed to come from the 

 same object, differ, then the one most interesting, practically 

 or cesthetically, is judged to be the true one. This law of 

 interest holds throughout — though a permanent interest, 

 like that of touch, may resist a strong but fleeting one like 

 that of pain, as in the case just given of the felon. 



3. The Summation of the Sense-spaces. 



Now for the next step in our construction of real space : 

 Jffoiv are the various sense-spaces added together into a 

 consolidated and unitary continuum ? For they are, in man 

 at all events, incoherent at the start. 



Here again the first fact that appears is that primitively 

 our space-experiences form a chaos, out of which we have no 

 immediate faculty for extricating them.. Objects of different 

 sense-organs, experienced together, do not in the first instance 

 appear either inside or alongside or far outside of each other, 

 neither spatially continuous nor discontinuous, in any definite 

 sense of these loords. The same thing is almost as true of 

 objects felt by difierent parts of the same organ before 

 discrimination has done its finished v.^ork. The most we 

 can say is that all our space-experiences together form an 

 objective total and that this objective total is vast. 



Even now the space inside our mouth, which is so inti- 

 mately known and accurately measured by its inhabitant 

 the tongue, can hardly be said to have its internal direc- 

 tions and dimensions known in any exact relation to those 

 of the larger world outside. It forms almost a little world 

 by itself. Again, when the dentist excavates a small cavity 

 in one of our teeth, we feel the hard point of his instrument 

 scraping, in distinctly difi'ering directions, a surface which 

 seems to our sensibility vaguely larger than the subsequent 

 use of the mirror tells us it ' really ' is. And though the 

 directions of the scraping difi"er so completely inter se, not 

 one of them can be identified with the particular direction 

 in the outer world to which it corresponds. The space of 

 the tooth-sensibility is thus really a little world by itself, 

 which can only become congruent with the outer space- 



