HISTORY OF THE ATOMIC THEORY. 79 



phenomena themselves, to be material." * — Ritter. But how- 

 ever this may be, it is not less astonishing than very much later 

 opinions which distinctly gave material form to ideas. Diogenes 

 was the last of this class who conceived the world to be a 

 living thing, in a narrow sense, and each individual as for a 

 time only able to live isolated, and to resist the influence of 

 the external and greater life which in the end enveloped all. 



We have seen air and matter made the flrst principles, and 

 now we find Heraclitus, of Ephesus, fixing on fire, which before 

 had been made to play an important part as heat, expanding 

 or contracting all things. In the absence of any full exposi- 

 tion of his reasoning, let us rather attempt, as with the others, 

 to complete it for ourselves. He seems to have thought that 

 wherever there is warmth there is life, where heat comes there 

 is motion and activity, it is the principle moving all things, a 

 secret fire which gives life to all things, it produces air, as we 

 see it constantly do when substances burn. Air again pro- 

 duces other elements. As fire produces air, so fire converts 

 water into air, and heat causes those changes in the atmos- 

 phere which produce water, whilst by its action on the earth 

 it produces land also, which is raised from the sea. As all 

 things have preceded fire, so in the end must fire swallow up 

 all things or all things will return to it. " The harmony of 

 the world arises from contrary forces, as that of the lyre and 

 the bow."t " The finest harmony is produced by opposites, 

 and every thing is produced by strife." But as with the others, 

 so with Heraclitus, fire was not common flame, but gradually 

 became an expression of force, and we still use the word in 

 this more spiritual sense. 



In Anaximander, of Miletus, we find the elements operated 

 on, and transformed by a power which he calls " the infinite," 

 and the higher forces are gradually developed out of the 

 lower. This, although an interesting chapter in the pro- 



• Page 190. t Page 214. 



