positedness of the subject-predicate relation, positedness of the combination posited in the formal "I combine" which belongs to judgment.
Aristotle had already come up against this meaning of being as subject-predicate relation or combination in his treatise Περί ἑρμηνείας, De interpretatione, "On assertion" or, better, "On interpretation." This treatise takes as its theme the logos or, more precisely, the λόγος ἀποφαντικός, that discourse and form of discourse whose function it is to exhibit that which is, as it is. Aristotle distinguishes between logos in general—discourse that has meaning and has some form, which can be a prayer, demand, or complaint—and λόγος ἀποφαντικός, discourse that has the specific function of displaying, which is called [in English, assertion, statement, proposition and] in German Aussage, Satz or, in a misleading way Urteil [judgment].
Aristotle first defines the λόγος ἀποφαντικός as a φωνὴ σημαντική, ἧς τῶν μερῶν τι σημαντικόν ἐστι κεχωρισμένον,2 an articulate sound in words which is capable of signifying something and in such a way that each part of this verbal complex, each single word, already signifies something for itself, the subject concept and the predicate concept. Not every logos or discourse is exhibitive discourse. Although all discourse is σημαντικός, or signifies something, nevertheless not all discourse has the function of exhibiting that which is, as it is. Only discourse ἐν ᾧ τὸ ἀληθεύειν ἢ ψεύδεσθαι ὑπάρχει,3 in which trueness and falseness occur, is exhibitive. Trueness, being-true, is a specific being (Sein). In the logos as assertion there is present, for one thing, in conformity with its form S is P, the "is," being as copula. For another, each logos as assertion is either true or false. Its being-true or being-false is connected in a certain way with the "is," being either identical with it or different from it. The question arises, How is being-true related to the being that is also present in the assertion in the sense of the "is" as copula? How must the problem be posed so as really to see this connection between truth and copula and to interpret it ontologically?
Let us first talk about how Aristotle sees the being of the copula. He says: αὐτά μὲν οὖν καθ᾽ αὑτὰ λεγόμενα τὰ ῥήματα ὀνόματα ἐστι καὶ σημαίνει τι, — ἵστησι γὰρ ὁ λέγων τὴν διάνοιαν, καὶ ὁ ἀκούσας ἠρέμησεν, — ἀλλ εἰ ἔστιν ἢ μή οὔπω σημαίνει· οὐ γὰρ τὸ εἶναι ἢ μὴ εἶναι σημεῖόν ἐστι τοῦ πράγματος, οὐδ᾿ ἐὰν τὸ ὂν εἴπῃς ψιλόν. αὐτὸ μὲν γὰρ οὐδέν ἐστιν, προσσημαίνει
2. Aristotle, De interpretatione, 4.16b26 f.
3. Ibid., 17a2f.