Platón, Sofista 256 e 5-6

Abstract

G.E.L. Owen has taken lines 256 e 5-6 in the Sophist to mean that a Form is many things and also is not, as a matter of identity, all those things which it is predicatively and in addition to them all those countless other things which it is also not predicatively.
In this paper it is argued that this interpretation can hardly be right given that it makes the text say something that does not follow from alleged premises of the lines in question. Those premises are contained in the stretch of argument starting at 256 e 3 and can be spelled out as three sets of three propositions each (“M” stands for Motion, “R” for Rest, “B” for Being, “S” for Sameness, “D” for Difference, “-” for the negation, “i” for the copula, and “X”, “Y” are variables for Forms):
(1) “Motion is Different from Sameness” “MiDS”
(2) “Motion is not-Sameness” “Mi-S”
(3) “Motion is the Same” “MiS”
(2) and (3) are not contradictories because in each of them “S” does not stand for the same thing.
Borrowing a bit of Fregean terminology, we can say that in (2) it denotes an argument, in (3) a function. The latter is in fact elliptical for “MiS(M)”.
(4) “Motion is Different from Difference” “MiDD”
(5) “Motion is not-Different” “Mi-D”
(6) “Motion is Different” “MiD”
Here, too, no contradiction arises. In (6) the function D is unsuturated and the proposition is elliptical for “MiD(X)”, Motion is different from numerous other Forms.
(7) “Motion is Different from Being” “MiDB”
(8) “Motion is not-Being” “Mi-B”
(9) “Motion is Being” “MiB”
By analogy with (3) and (6), “Being” in (9) stands for a function, hence the sense of the verb is predicative. As with (6), (9) is elliptical for “MiB(X)”, a Form is many other things.
Propositions (1)-(9) show that the Eleatic Visitor construes negative expressions as denials of identity attaching the negation sign to the predicative and treating the latter as an argument and not as a function.
In 256 e 5-6 he generalizes to the effect that the truth value of sentences corresponding to (3), (6) and (9) i.e. of sentences of the form “YiB(X)”, is true for many substitutions of the subject term and the predicate term. But for many it is not. In opposition to this sentences obtained by generalization from (8) i.e. sentences of the form “Yi-B” are true in countless cases in fact in all cases but one: that of B
[A.G.L.]