Simpl. _de Coelo_ 137 r; Schol. Aristot. 509 b; cf. Aristokl. Euseb. _Pr. Ev._ xiv. 17. (Fr. 17) This argument is the strongest proof that being is one only. And the proofs are as follows: For if a multiplicity of things existed it would be necessary that these things should be just such as I say the one is. For if earth exists, and water and air and iron and gold and fire and the living and the dead and black and white, and everything else which men say is real,—if these things exist and we see and hear them correctly, it is necessary that each thing should be such as we first determined, namely, it should not change its character or become different, but should always be each thing what it is. Now we say that we see and hear and understand correctly; but it seems to us that hot becomes cold and cold hot, that hard becomes soft and soft hard, that the living being dies and life comes from what is not living; and that all these things become different, and what they are is not like what they were. It seems to us that iron, being hard to the touch, wastes away †becoming liquefied,†[71] and so does gold, and rock, and whatever else seems to be strong, so that we conclude that we do not see or know things that are. And earth and rock arise from water. These things then do not harmonise with each other. Though we said that many things are eternal, and have forms and strength, it seems that they all become different and change their character each time they are seen. Evidently we do not see correctly, nor is the appearance of multiplicity correct; for they would not change their character if they were real, but would remain each thing as it seemed, for nothing is nobler than that which is real. But if they change their character, being perishes and not-being comes into existence. So then if a multiplicity of things exist, it is necessary that they should be such as the one is. (_b_) ARISTOTLE’S ACCOUNT OF MELISSOS. _Phys._ i. 3; 186 a 6. Both Melissos and Parmenides argue fallaciously, and they make false assumptions and their reasonings are not logical; but the argument of Melissos is the more wearisome, for it sets no problem, but granted one strange thing, others follow; and there is no difficulty in this. The error in the reasoning of Melissos is plain, for he thinks that if everything which has come into being has a beginning, he can assume that that which has not come into being does not have a beginning. This, then, is strange, that he should think that everything has a beginning except time, and this does not, and that simple generation has no beginning but change alone begins, as though change as a whole did not come into being. Even if the all is a unity, why then should it not move? Why should not the whole be moved even as a part of it which is a unity, namely water, is moved in itself? Then why should there not be change? It is not possible that being should be one in form, but only in its source.