excluded it.[1] It is totally unlike anything we meet with in earlier days.
This suggests at once that it is only in the vortex that the atoms acquire weight and lightness,[2] which are, after all, only popular names for facts which can be further analysed. We are told that Leukippos held one effect of the vortex to be that like atoms were brought together with their likes.[3] Here we seem to see the influence of Empedokles, though the "likeness" is of another kind. It is the finer atoms that are forced to the circumference, while the larger tend to the centre. We may express that by saying that the larger are heavy and the smaller light, and this will amply account for everything Aristotle and Theophrastos say; for there is no passage where the atoms outside the vortex are distinctly said to be heavy or light.[4]
There is a striking confirmation of this view in the atomist cosmology quoted above.[5] We are told there that the separation of the larger and smaller atoms was due to the fact that they were "no longer able to revolve in equilibrium owing to their number," which implies that they had previously been in a state of "equilibrium" or "equipoise." Now the word ἰσορροπία has no necessary implication of
- ↑ The Aristotelian criticisms which may have affected Epicurus are such as we find in De caelo, A, 7. 275 b 29 sqq. Aristotle there argues that, as Leukippos and Demokritos made the φύσις of the atoms one, they were bound to give them a single motion. That is just what Epicurus did, but Aristotle's argument implies that Leukippos and Demokritos did not. Though he gave the atoms weight, even Epicurus could not accept Aristotle's view that some bodies are naturally light. The appearance of lightness is due to ἔκθλιψις the squeezing out of the smaller atoms by the larger.
- ↑ In dealing with Empedokles, Aristotle expressly makes this distinction. Cf. De caelo, B, 13, especially 295 a 32 sqq., where he points out that Empedokles does not account for the weight of bodies on the earth (οὐ γὰρ ἥ γε δίνη πλησιάζει πρὸς ἡμᾶς), nor for the weight of bodies before the vortex arose (πρὶν γενέσθαι τὴν δίνην).
- ↑ Diog. loc. cit. (p. 338).
- ↑ This seems to be in the main the view of Dyroff, Demokritstudien (1899), pp. 31 sqq., though I should not say that lightness and weight only arose in connexion with the atoms of the earth (p. 35), If we substitute "world" for "earth," we shall be nearer the truth.
- ↑ See above, p. 338.
