a narrower sense, which comes out clearly only when the before and after receive further interpretation. Primarily, πρότερον-ὕστερον means for Aristotle before and after in the sequence of places. It has a non-temporal sense. But the experience of before and after intrinsically presupposes, in a certain way, the experience of time, the earlier and later. Aristotle dealt with the πρότερον and ὕστερον in detail in book Delta of the Metaphysics (11.1018b 9ff). In the treatise on time he wavers in his conception of the πρότερον-ὕστερον. Most often he takes it directly as earlier and later and not so much in the sense of before and after. He says of them that they have an ἀπόστασις πρὸς τὸ νῦν,27 a distance from the now; in the then a now is concomitantly thought each time as not-yet-now, and similarly in the at-the-time the now concomitantly thought appears as the no-longer-now. The now is the limit for what has gone by and what comes after.
The nows which we count are themselves in time: they constitute time. The now has a peculiar double visage, which Aristotle expresses in this way: καὶ συνεχής τε δὴ ὁ χρόνος τῷ νῦν, καὶ διῄρηται κατὰ τὸ νῦν.28 Time is held together within itself by the now; time's specific continuity is rooted in the now. But conjointly, with respect to the now, time is divided, articulated into the no-longer-now, the earlier, and the not-yet-now, the later. It is only with respect to the now that we can conceive of the then and at-the-time, the later and the earlier. The now that we count in following a motion is in each instance a different now. Τὸ δὲ νῦν διὰ τὸ κινεῖσθαι τὸ φερόμενον αἰεὶ ἕτερον,29 on account of the transition of the moving thing the now is always another, an advance from one place to the other. In each now the now is a different one, but still each different now is, as now, always now. The ever different nows are, as different, nevertheless always exactly the same, namely, now. Aristotle summarizes the peculiar nature of the now and thus of time—when he interprets time purely by way of the now-in a manner so pregnant that it is possible only in Greek but hardly in German or English: τὸ γάρ νῦν τὸ αὐτὸ ὁ ποτ᾿ ἦν, τὸ δ᾿ εἶναι auto ἕτερον;30 the now is the same with respect to what it always already was—that is, in each now
27. Physica, book 4, 14.223a 5f. [πρότερον γάρ καὶ ὕστερον λέγομεν κατὰ τὴν πρὸς τὸ νῦν ἀπόστασιν; "for we say 'before' and 'after' with reference to the distance from the 'now."' Trans. Hardie and Gaye.]
28. Physica, book 4, 11.220 a 5. ["Time, then, also is both made continuous by the 'now' and divided at it." Trans. Hardie and Gaye.]
29. Ibid., 220a 14.
30. Ibid., 219b 10f. ["But every simultaneous time is self-identical; for the 'now' as a subject is an identity, but it accepts different attributes." The translators note: "E.g., if you come in when I go out, the time of your coming in is in fact the time of my going out, though for it to be the one and to be the other are different things." Trans. Hardie and Gaye. Compare the Wicksteed and Cornford translation: "But at any given moment time is the same everywhere, for the 'now' itself is identical in its essence, but the relations into which it enters differ in different connexions."]