opposition, which itself consists of two principles. At least these three (two) ἀρχαί are necessary; no more are required. τρόπον δέ τινα ἄλλον οὐκ ἀναγκαῖον.5 In another sense, however, the principles governing the possibility of μεταβολή need not be regarded as three. ἱκανὸν γὰρ ἔσται τὸ ἕτερον τῶν ἐναντίων ποιεῖν τῇ ἀπουσίᾳ καὶ παρουσίᾳ τὴν μεταβολήν,6 as it suffices for the possibility of change that one thing displaces another, i.e. that change is brought about simply by ἀπουσία (absence) or παρουσία (presence).
This passage, considered in its total context, is of significance for us in several respects. Initially there are two linguistic forms of the familiar word ουσία. These forms bring to expression two possible meanings of ουσία: ab-sence [Ab-wesenheit] and pre-sence [An-wesenheit]. They clearly indicate that the concept of ουσία involves absence and presence. At the same time, however, one can also say that if ἀπουσία-παρουσία means absence-presence, then ουσία just means essencehood [Wesenheit]. i.e. something which hovers over both without being either. So what we have maintained is not the case, i.e. ουσία does not mean presence at all. The Greeks express presence by napουσία. This formal linguistic objection appears irrefutable. In fact, it cannot be refuted at a linguistic leveL nor by appealing to what is directly and expressly intended in everyday usage of the word, because our thesis that ουσία means constant presence simply does not rest on such considerations.
What we intend by the asserted fundamental meaning will be discussed below. For the moment we hold to the meaning of ουσία in its possible modifications as absence and presence.
(παρ) ουσία
/ \
παρουσία ἀπουσία
The παρουσία which is explicitly set off against ἀπουσία presupposes the primordial παρουσία. Just how this is possible remains problematic, not merely in the sense of a philological difficulty concerning the interpretation of Greek philosophical concepts, but as a fundamental substantive problem.
5 Physics 191 a 5 f. ('Yet in another way of putting it this is not necessary'; trans. Hardie and Gaye . )
6 Physics 191 a 6 f. ('One of the contraries will serve to effect the change by its successive absence and presence'; trans. Hardie and Gaye.)
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