610 PSYCHOLOGY. 



as parts of this duration-block that the relation ol succession 

 of one end to the other is perceived. We do not first feel 

 one end and then feel the other after it, and from the per- 

 ception of the succession infer an interval of time between, 

 but we seem to feel the interval of time as a Avliole, with its 

 two ends embedded in it. The experience is from the out- 

 set a synthetic datum, not a simple one ; and to sensible 

 perception its elements are inseparable, although attention 

 looking back may easily decompose the experience, and 

 distinguish its beginning from its end. 



When we come to study the perception of Space, we 

 shall find it quite analogous to time in this regard. Date 

 in time corresponds to position in space ; and although we 

 now mentally construct large spaces by mentally imagin- 

 ing remoter and remoter positions, just as we now construct 

 great durations by mentally prolonging a series of success- 

 ive dates, yet the original exj)erience of both space and 

 time is always of something already given as a unit, inside 

 of which attention afterward discriminates parts in relation 

 to each other. Witliout the parts already given as in a time 

 and in a space, subsequent discrimination of them could 

 hardly do more than perceive them as different from each 

 other ; it would have no motive for calling the difference 

 temporal order in this instance and spatial position in that. 

 And just as in certain experiences we may be conscious 

 of an extensive space full of objects, without locating each 

 of them distinctly therein ; so, when many impressions fol- 

 low in excessively rapid succession in time, although we 

 may be distinctly aware that they occupy some duration, 

 And are not simultaneous, we may be quite at a loss to tell 

 which comes first and which last ; or we may even invert 

 their real order in our judgment. In complicated reaction- 

 time experiments, where signals and motions, and clicks 

 of the apparatus come in exceedingly rapid order, one is 

 at first much perplexed in deciding what the order is, yet 

 of the fact of its occupancy of time we are never in doubt. 



" la diiree dans la succession; on ne I'y trouvera jamais; la duree a preceda 

 la succession ; la notion de la duree a precede la notion de la succession. 

 Ellc en est done tout-a-fait independante, dira-t-on? Qui, elle en est tout- 

 ^-fait independante." 



