Did the Stoics then regard the universe as finite or as infinite? In answering this question we must distinguish our terms, as they did. The All, they said, was infinite, but the Whole was finite. For the 'All' was the cosmos and the void, whereas the 'Whole' was the cosmos only. This distinction we may suppose to have originated with the later members of the school. For Appolodorus noted the ambiguity of the word 'All' as meaning, (1) the cosmos only, (2) cosmos + void If then by the term "universe" we understand the cosmos, or ordered whole, we must say that the Stoics regarded the universe as finite. All being and all body, which was the same thing with being, had necessarily bounds, it was only not being, which was boundless. Another distinction, due this time to Chrysippus himself, which the Stoics found it convenient to draw, was between the three words 'void,' 'place' and 'space'. Void was defined as 'the absence of body', place was that which was occupied by body, the term 'space' was reserved for that which was partly occupied and partly unoccupied. As there was no corner of the cosmos unfilled by body, space, it will be seen, was another name for the All. Place was compared to a vessel that was full, void to one that was empty, and space to the vast wine-cask, such as that in which Diogenes made his home, which was kept partly fully, but in which there was always room for more. The last comparison must of course not be pressed. For if space be a cask, it is one without top, bottom or sides. But while the Stoics regarded our universe as an island of being in an ocean of void, they did not admit the possibility that other such islands might exist beyond our ken. The spectacle of the starry heavens, which presented itself nightly to their gaze in all the brilliancy of a southern sky--that was all there was of being, beyond that lay nothingness. Democritus or the Epicureans might dream of other worlds, but the Stoics contended for the unity of the cosmos as staunchly as the Mahometans for the unity of God, for with them the cosmos was God. In shape they conceived of it as spherical, on the ground that the sphere was the perfect figure and was also the best adapted for motion. Not that the universe as a whole moved. The earth lay in its centre, spherical and motionless, and round it coursed the sun, moon, and planets, fixed each in its respective sphere as in so many concentric rings, while the outermost ring of all, which contained the fixed stars, wheeled round the rest with an inconceivable velocity.