What is, as such and as a whole, the Greeks call φύσις. Let it be mentioned just in passing that already within Greek philosophy, a narrowing of the word set in right away, although its original meaning did not disappear from the experience, the knowledge, and the attitude of Greek philosophy. An echo of knowledge about the original meaning still survives in Aristotle, when he speaks of the grounds of beings as such (cf. Metaphysics Γ 1, 1003a27).13 
But this narrowing of φύσις in the direction of the “physical” did not happen in the way we picture it today. We oppose to the physical the “psychical,” the mind or soul, what is ensouled, what is alive. But all this, for the Greeks, continues even later to belong to φύσις. As a counterphenomenon there arose what the Greeks call θέσις, positing, ordinance, or νόμος, law, rule in the sense of mores. But this is not what is moral, but instead what concerns mores, that which rests on the commitment of freedom and the allotment of tradition; it is that which concerns a free comportment and attitude, the shaping of the historical Being of humanity, ἦθος, which under the influence of morality was then degraded to the ethical.
Φΰσις gets narrowed down by contrast to τέχνη—which means neither art nor technology but a kind of knowledge, the knowing disposal over the free planning and arranging and controlling of arrangements (cf. Plato’s Phaedrus).14 Τέχνη is generating,
13. “Now since we are seeking the principles and the highest causes [or grounds], it is clear that these must belong to some φύσις in virtue of itself. If, then, those who were seeking the elements of beings [τῶν ὄντων] were also seeking these principles, these elements too must be elements of being [τοῦ ὄντος], not accidentally, but as being. Accordingly, it is of being as being that we, too, must find the first causes.”—Metaphysics Γ 1, 1003a26–32.
14. Phaedrus 260d–274b is devoted to determining how rhetoric can become a proper τέχνη and to what is required in general of a proper τέχνη.