ARISTOTLE AND THE EARLIER PERIPATETICS vol.I by Eduard Zeller, B.F.C.Costelloe 1897

''
Ibid.
PHYSICS 485
elements, as Heraclitus and Plato had already demonstrated,
1 form together one complete whole, a selfcontained
circle of generation and destruction, 2 the parts
of which are incessantly undergoing transformation, but
steadfastly maintaining the law of their metamorphosis,
preserving the same forms and proportions in the midst
of the ceaseless transmutation of their matter. 3
These propositions concerning the nature of the
elementary bodies are enough to prove that there is
only one world.
For if each body has its natural place,
and if its very essence consists in its having it, then all
bodies, unless hindered by force, must move to these
their natural localities—earth to the centre, aether to
circumference, and the other elements to the intermediate
spaces. Hence it is impossible that there
should be more than one region of earth, water, air,
fire, and eether, and consequently that there should be
another world besides the one in which we live. We
cannot suppose that a body is forcibly retained in a
locality beyond the world, since such a locality must be
1
Cf. ZELL. Ph. d. Gr. i. tovto Kal iriGaybv, is aSitvaroi/ fiij
619, and ibid. ii. 680. rbv ainbv elvat irepl irdvTwv tovtuv
2
Gen. et Corr. ibid. 331, b, 2: \6yov, Kal 5iav re Kal tpSopav elvai Kal yiveaiv,
3
Meteor, ii. 3, 357, b, 27 : it toutjjj/ p.4vtoi rerayp-evcos trvuPa'-
is asked, irorepov Kal t\ BdAarra yeip irainv avTOts. 358, b, 29
ael Stap.di'zi twv alr&v oicra p.opiai> oUre ael tJ aura pepy Siap.4vet, aire
a.pi9p.