Heidegger is particularly aware that the common reading of Aristotle’s notion of οὐσία as raw Substance is far from Aristotle’s own understanding. Heidegger observes that the “central phenomenon” explicated in Aristotle’s Physics is “das Seiende im Wie seines Bewegtseins” ([individual] being in the how of its movement). Neither Aristotle nor Heidegger is concerned with things as mere objects, but with the world as it is encountered. The most vivid paradigm employed by both to represent and to reflect upon this encounter is the experience of the production of an artifact. Heidegger describes ποίησις (creating, production) in terms of a Fore-having of the world as a fundamental ontological structure. He then asks, “How does this ontological structure arise?” and responds: “The investigations ... must impart a possible access to the actual origin of Aristotle's ontology.”

In circumspection, life is “there” in the concrete “how” of a that of engagement. The Being of this “that” is ... characterized ... as that which can be other [than what it is in contrast to] that which is necessary and always what it is.38 One arrives at this ontological characteristic through negation of an other, actual Being. This [other, actual Being] ... arises in its categorial structure out of a definitely executed, ontological radicalization of the idea of a moving being. Exemplary for this possible identification of its meaning structure is the movement of production ... The Being of life occurs as a transpiring movement ... This movement is ἕξις [habit] as σοφία [wisdom]. In fact, the Being of life must be seen in the temporality of σοφία as such ... Every movement is ... a being under way ..., a not having yet arrived at its goal ... The Being character of ἕξις [habit] and thereby of ἀρετή [excellence, virtue], that is, the ontological structure of humanity, is understood in terms of an ontology of beings as the “how” of a definite movement and in the ontological radicalization of the idea of this movement. (emphasis added)

Heidegger later says that what is decisive is to demonstrate for Aristotle that the traditional ontology based on categories of Being and Non-Being, otherness, and difference is incapable of understanding the phenomenon of movement.

This phenomenon gives itself from out of its own original and final structures: δύναμις [possibility, ύλη], that is always a definite having at one’s disposal, ἐνέργεια [actuality, ἐιδος], that which is taken in application at one’s disposal, and ἐντελέχεια [goal], that is the applied in the custodial holding of what is at one’s disposal.

The typically Aristotelian formulation of the ontological structure of human experience is clear in Heidegger’s vocabulary and description of the human activity of the production of an artifact, for Heidegger’s description is a classic example of the triadic structure of becoming in Aristotle: Metaphysics Γ6 and Κ6 both describe this structure as one of contraries related by privation to a “substrate.” According to Aristotle, however, this “substrate” is nothing tangible. The production of an artifact is unequivocally and radically grounded in movement or possibility inseparable from a concrete circumstance. Although in no way tangible, possibilities are never a “mere nothing” or “arbitrary.” Possibilities are the conditio sine quo non of any and all event, and they are inseparable from a given situation. This is precisely how Aristotle speaks of ύλη (matter).

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