From Chapter VIII., The Younger Eleatics

168. Opposition to Ionians
Eleaticism was always critical, and we are not without indications of the attitude taken up by Melissos towards contemporary systems. The flaw which he found in the Ionian theories was that they all assumed some want of homogeneity in the One, which was a real inconsistency. Further, they all allowed the possibility of change; but, if all things are one, change must be a form of coming into being and passing away. If you admit that a thing can change, you cannot maintain that it is eternal. Nor can the arrangement of the parts of reality alter, as Anaximander, for instance, had held; any such change necessarily involves a coming into being and passing away.

The next point made by Melissos is somewhat peculiar. Reality, he says, cannot feel sorrow or pain; for that is always due to the addition or subtraction of something, which is impossible. It is not easy to be sure what this refers to. Perhaps it is to the theory by which Anaxagoras explained perception.⁶⁰

Motion in general⁶¹ and rarefaction and condensation in particular are impossible; for both imply the existence of empty space. Divisibility is excluded for the same reason. These are the same arguments as Parmenides employed.

60. See p. 273. It is clear that Anaxagoras made considerable use of pain (πόνος), and it is possible that his doctrine, summed up in the words ἀεὶ πονεῖ τὸ ζῷον (Arist. Eth. Nic. H, 15. 1154b 7) had a wider application than appears from his remains. Aristotle (De caelo, B, 1. 284 a 15) makes a point of the οὐρανός being ἄπονος.

61. The view of Bäumker that Melissos admitted ἀντιπερίστασις or motion in pleno (Jahrb. f. Kl. Phil., 1886, p. 541; Das Problem der Materie, p. 59) depends upon some words of Simplicius (Phys. p. 104, i3), οὐχ ὅτι μὴ δυνατὸν διὰ πλήρους κινεῖσθαι, ὡς ἐπὶ τῶν σωμάτων λέγομεν κτλ.. These words were formerly turned into Ionic and passed off as a fragment of Melissos. They are, however, part of Simplicius's own argument against Alexander, and have nothing to do with Melissos at all.