1 84 THE GRAMMAR OF SCIENCE 



distinction between the two, we are often hardly certain 

 whether we are distinguishing things by time or by space, 

 IV/iy we perceive things under these modes, the scientist 

 is content to classify with all other w/ij/s as an idle and 

 irrational question ; but clearer views as to the /low of 

 these modes of perception will undoubtedly come with 

 the growth of physiological psychology, and with in- 

 creased observation of the manner in which the lower 

 forms of life and young children discriminate perceptions. 

 Of time as of space we cannot assert a real existence ; 

 it is not in things, but is our mode of perceiving them. 

 As we cannot postulate anything of the beyond of sense- 

 impression, so we cannot attribute time directly or in- 

 directly to the supersensuous. Like space, it appears 

 to us as one of the plans on which that great sorting- 

 machine, the human perceptive faculty, arranges its 

 material. Through the doorways of perception, through 

 the senses of man, crowd, in our waking state, sense- 

 impression upon sense - impression ; sound and taste, 

 colour and warmth, hardness and weight — all the various 

 elements of an infinite variety of phenomena, all that 

 forms for us reality — crush through the open gateways. 

 The perceptive faculty, sharpened by long centuries of 

 natural selection,^ sorts and sifts all this mass of sense- 

 impressions, giving to each a place and an instant. Thus 

 the magnitude of space and time depends upon no 

 external world independent of ourselves, but on the com- 

 plexity of our sense-impressions, immediate and stored. 

 Infinity of space or eternity of time has no meaning in 

 the field of perception, because the correlation and 

 sequence of our perceptions, wide as both undoubtedly 

 are, do not require these enormous frames to exhibit 

 them. Where the senses perceive no object, there there 

 is no space, for there no groups of sense-impressions are 

 to be distinguished. Where I can no longer carry back 



1 We cannot infer the time and space-modes of perception except for per- 

 ceptive faculties, more or less similar to our own. The order of phenomena 

 in both space and time is essentially conditioned by the intensity and quality 

 of the consciousness (p. 83). 



