166 PBTCEOLOGY. 



every sensible total may be subdivided b}' discriminative 

 attention into sensible parts, wliich are also spaces, and 

 into relations between the parts, these being sensible spaces 

 too. Furthermore, we have seen (in a foot-note) that difier- 

 ent parts, once discriminated, necessarily fall into a deter- 

 minate order, both by reason of definite gradations in their 

 quality, and by reason of the fixed order of time-succes- 

 sion in which movements arouse them. But in all this 

 nothing has been said of the comparative measurement of 

 one sensible space-total against another, or of the way 

 in which, by summing our divers simple sensible space- 

 experiences together, we end by ronstructing what we re- 

 gard as the unitary, continuous, and infinite objective Space 

 of the real world. To this more difficult inquiry we next 

 pass. 



THE CONSTRUCTION OF 'REAL' SPACE. 



The problem breaks into two subordinate problems . 



(1) Hoio is the subdivision and measurement of the several 

 sensorial spaces completely effected? and 



(2) Hoiv do their mutual addition and fusion and reduction 

 to the same scale, in a word, hoiv does their synthesis, occur? 



I think that, as in the investigation just finished, we 

 found ourselves able to get along without invoking any data 

 but those that pure sensibility on the one hand, and the 

 ordinary intellectual powers of discrimination and recollec- 



fall between. Thus those psychologists who set little store by local signs 

 and great store by movements in explaining space-perception, would have 

 a perfectly definite time-order, due to motion, by which to account for 

 the definite order of positions that appears when sensitive spots are excited 

 all at once. Without, however, the preliminary admission of the ' ulti- 

 mate fact' that this collective excitement shall feel like a line and nothing 

 else, it can never be explained why the new order should needs be an 

 order of positions, and not of merely ideal serial rank We shall heieafter 

 have any amount of opportunity to observe how thoroughgoing is the par- 

 ticipation of motion in all our spatial measurements. Whether the local 

 signs have their respective qualities evenly graduated or not, the feelings 

 of transition must be set down as among the vercf causm in localization. 

 But the gradation of the local signs is hardly to be doubted; so we may be- 

 lieve ourselves really to possess two sets of reasons for localizing any point 

 we may happen to distinguish from out the midst of any line or any larger 

 space. 



