THE RELATIVITY OF KNOWLEDGE 



have not escaped the difficulty which confronted 

 us at the outset. For each of these particles, if 

 divisible, is a piece of matter just like the block 

 of metal or wood with which we set out, — only- 

 smaller in size. The particles of these particles 

 cannot, as we have seen, be in direct contact ; 

 then they must each be composed of several 

 particles not in contact, but exerting on each 

 other attractive and repulsive forces that vary 

 inversely with the squares of their distances 

 apart ; and again we have to ask of these parti- 

 cles, Are they divisible, or indivisible ? and so 

 on, forever. 



Such are the difficulties into which we are led 

 if we assume that the atoms of which matter is 

 composed are divisible. Let us now assume 

 that (as their name implies) they are indivisible. 

 And this is, no doubt, the assumption which is 

 most congruous with the experiences of the 

 chemist. Yet we shall find that an absolutely 

 indivisible atom is quite inconceivable by human 

 intelligence. Every such atom, if it exists, must 

 have an upper side and an under side, a right 

 side and a left side, or if spherical, must have a 

 periphery that is conceived as covering some 

 assignable area. Now by no effiart of our intel- 

 ligence can we imagine sides so close together 

 that no plane of cleavage can pass between 

 them ; nor can we imagine a sphere so minute 

 that it cannot be conceived as divisible into 



