SPACE AND TIME 159 



coexisting phenomena, what we may term real space, and 

 the space of our thought, the conceptual space of 

 geometry, what we may term ideal space. This latter, as 

 we shall see in the sequel, may be conceived as either 

 finite or infinite, although a limited portion of ideal 

 infinite space describes most easily the real space of our 

 perceptions. Thus the only infinite space we know of, so 

 far from being a real immensity overwhelming our finite 

 capacities, is a product of our own reasoning faculty. 

 On the other hand, cosmical space, the mode of our per- 

 ception, is finite and limited by the range, not of what we 

 imagine, but of what we actually perceive to coexist. 

 The mystery of space, whether it be the finite space of 

 perception or the infinite space of conception, lies in, and 

 not outside, each human consciousness. We must seek it 

 either in our power of distinguishing (or of perceiving 

 apart) so many and varied groups of sense -impressions, 

 or in our power of drawing conceptions, which enables 

 us to pass from the finite real to the infinite ideal. Only 

 for us, as perceiving human beings, has space any mean- 

 ing ; we cannot infer it where we do not find psychical 

 machinery similar to our own. 



S 3. — TJie Infinite Divisibility of Space 



The space of our perceptions, as we have seen, is 

 finite and varies from individual to individual with the 

 range and complexity of his perceptions. As it is just 

 large enough for our perception of phenomena, so it is 

 just small enough, by which we are to understand that it 

 is not " infinitely divisible." The limit to its divisibility 

 is the limit to our power of perceiving things apart. Our 

 organs of sense are such that only sense-impressions of a 

 certain intensity or amplitude fall within their cognisance. 

 We may resolve phenomena into smaller and smaller 

 groups of sense- impressions, but we ultimately reach a 

 limit at which the sense-impression ceases. We may 

 divide a piece of paper up into more and more minute 

 fragments, but ultimately they cease to be sensible even 



