When Heidegger declares that natural beings are what they are by way of a kind of κίνησις, he must thus be expanding the notion of κίνησις beyond the strict sense it has in the technical definition of the term by which Aristotle distinguishes it from Being in book III of the Physics. Why would Heidegger want to do so? Because, notwithstanding the above emphatic and clear distinction between changing and Being, Heidegger sees, in Aristotle’s thinking of the way of being of natural beings, an initial recognition of a kind of essential incompletion there as well, even if this must be distinguished from the incompletion of κίνησις strictly speaking.
This is the second radical interpretive move, for Heidegger sees Aristotle as observing natural beings—in the way the form orders the material into a way of being, or the soul actualizes the body’s potency, into a way of life for living things—and he finds Aristotle’s text here gesturing to a moment of non-presence. This is the case and it is detectible through destructive reading, even if Aristotle ultimately sets aside such non- presence and affirms the metaphysics of presence that he will pass down to the tradition through the concepts he establishes. Consider the following.
Heidegger writes:
A being thus in the world is there and can, at the same time be something usable. Δύναμις, “not yet,” can mean: is usable for ... transformable into ... This being that is there thus, as there completed and usable for ... is characterized by διχῶς [doubleness, duplicity] as a being ... Even a house is for the most part in everydayness in such a way that something is lacking in it, characterized by στέρησις [privation]. Aristotle proceeds from this point in determining movement. (BCArP 212/313)
That is, insofar as natural beings are what they are through the actualization of potency, they are both present, sitting there before us, and essentially lacking, constituted in their very being by what is not present, by a “not yet.”18 Moreover, Heidegger sees Aristotle’s questioning insight into this duplicity of natural beings, their double way of being, as emerging explicitly from his attending to a feature of things as they themselves present in everyday experience. In this being potentially usable there is an ontological lack, and there Heidegger wants to see a certain kind of “movement” or dynamism, a kinetic way of being (even if this cannot be the technical sense of κίνησις that Aristotle distinguishes emphatically from the εἶναι or “being” of a natural being).
Heidegger clarifies what is entailed by the account of this kinetic way of being, writing:
18. See Brogan, who in Heidegger and Aristotle places a “twofoldness of Being” right at the center of Heidegger’s reading of Aristotle.