as the principle of motion is itself a way of being: namely, that way of being that determines the being of those beings capable of moving from out of themselves. In short, the opening of the seminar is meant to leave no doubts about Heidegger’s intention of reading the Physics from a strictly ontological perspective. As we have seen Heidegger maintain in previous seminars, the Physics is a work of ontology, not the ontic study of the properties of a determinate class of beings (see also GA18, 284, 291).4
The next move of the seminar, indicated by Weiss (WP3, 1) and further elaborated upon by the published protocol, is accordingly to note an important parallel between being and motion: neither is a genus existing beyond the particular ways of being or of being in motion. Specifically, just as there are different ways of being corresponding to the different categories, so there are different ways of being in motion corresponding to different categories. As both Weiss (WP3, 1) and the published protocol note (GA83, 230), the only sense in which being is something common (κοινόν) for Aristotle is the sense of pros hen (in relation to one): being in the sense of the other categories all relate to the primary sense, which is being in the category of “substance.” Motion simply follows being here, both in the diversity of senses and in their pros hen relation. Heidegger is commenting on Aristotle’s claim that “there is no motion beyond the things themselves” (200b32–33; οὐκ ἔστι δὲ κίνησις παρὰ τὰ πράγματα). According to Heidegger, the specific target of this claim is Plato in the Sophist 254 (see also GA18, 288). This is where the Visitor speaks of motion (κίνησις), rest (στάσις), and being (τὸ ὄν) as “the greatest among the genera” (254d4–5; μέγιστα τῶν γενῶν). None of these is for Aristotle a “genus” given the different senses of being. The published protocol notes that the senses of being are not even limited to the categories, but also include being in the sense of truth, accidental being, and being in the sense of dunamis and entelecheia (GA83, 229). This comment is instigated by lines 200b26–28, where Aristotle lists the latter sense of being along with the categories: and of course, it is being in the sense of dunamis and entelecheia that will prove essential to defining motion across (not above!) the categories.
Another line that receives attention in this first class is 200b28–29, where Aristotle introduces the pros ti relation as characterizing motion: as he claims immediately before the sentence cited above, the mover is always the mover of a moved and the moved is always moved by a mover (200b31–32). This is why, as the Weiss notes specify (WP3, 1), motion, as a from-to, is in every category characterized by stretch and extension (Spannung,
4. What Mora says of Heidegger’s reading in 1931 is true earlier as well: Aristotle’s Physics “non va più intesa come filosofia della natura, non studia le condizioni a priori di essa, non é scienza teoretica parziale che esamina l’essere in divenire, ma assume il ruolo conduttore di scienza dell’essere in quanto essere tout court, esaurisce nel suo studio la totalitá dell’essere, diviene cioè a pieno titolo ontologia, che in sé racchiude tutto l’essere” (2000, 35). If Mora claims that this is not true of Heidegger’s reading of the Physics during the period of Being and Time and that he then interprets the Physics traditionally as an ontology of nature (see 219–220), this is refuted by the 1928 seminar where the approach to the Physics is perfectly described by the cited words.