The real reason is given in the paraphrase in Simpl. _Phys._ p. 103, 21 (R. P. 142 a), συγχωρεῖται γὰρ καὶ τοῦτο ὑπὸ τῶν φυσικῶν, though of course Melissos himself would not have put it in that way. He regarded himself as a φυσικός like the rest; but, from the time of Aristotle, it was a commonplace that the Eleatics were not φυσικοί, since they denied motion. Footnote 908: This has been denied by Offner, “Zur Beurtheilung des Melissos” (_Arch._ iv. pp. 12 sqq.), but I now think he goes too far. Cf. especially _Top._ ix. 6, ὡς ἄμφω ταὐτὰ ὄντα τῷ ἀρχὴν ἔχειν, τό τε γεγονὸς καὶ τὸ πεπερασμένον. The same point is made in _Soph. El._ 167 b 13 and 181 a 27. Footnote 909: The words ἀλλ’ ἄπειρόν ἐστι mean simply “but it is without limit,” and this is simply a repetition of the statement that it has no beginning or end. The nature of the limit can only be determined by the context, and accordingly, when Melissos does introduce the subject of spatial infinity, he is careful to say τὸ μέγεθος ἄπειρον (fr. 3). [Sidenote: Reality spatially infinite.] 167. Melissos did indeed differ from Parmenides in holding that reality was spatially as well as temporally infinite; but he gave an excellent reason for this belief, and had no need to support it by the extraordinary argument just alluded to. What he said was that, if it were limited, it would be limited by empty space. This we know from Aristotle himself,[910] and it marks a real advance upon Parmenides. He had thought it possible to regard reality as a finite sphere, but it would have been difficult for him to work out this view in detail. He would have had to say there was nothing outside the sphere; but no one knew better than he that there is no such thing as nothing. Melissos saw that you cannot imagine a finite sphere without regarding it as surrounded by an infinite empty space;[911] and as, in common with the rest of the school, he denied the void (fr. 7), he was forced to say reality was spatially infinite (fr. 3). It is possible that he was influenced in this by his association with the Ionic school. Footnote 910: Arist. _Gen. Corr._ i. 8. 325 a 14, ἓν καὶ ἀκίνητον τὸ πᾶν εἶναί φασι καὶ ἄπειρον ἔνιοι· τὸ γὰρ πέρας περαίνειν ἂν πρὸς τὸ κενόν. That this refers to Melissos has been proved by Zeller (p. 612, n. 2). Footnote 911: Note the disagreement with Zeno (§ 162). From the infinity of reality, it follows that it must be one; for, if it were not one, it would be bounded by something else (fr. 5). And, being one, it must be homogeneous throughout (fr. 6_a_), for that is what we mean by one. Reality, then, is a single, homogeneous, corporeal _plenum_, stretching out to infinity in space, and going backwards and forwards to infinity in time. [Sidenote: Opposition to Ionians.]