Physis, Logos, and the Greek Beginning

The Greek word physis — usually translated as "nature" — does not, for Heidegger, primarily mean the natural world as opposed to the artificial or the supernatural. It names the self-arising, self-sustaining emergence of beings into presence: the coming-into-appearance of what is, understood as an active, self-grounding process. The flower that blooms and the stone that lies in the sun both participate in physis insofar as they simply are, maintaining their presence without external support. This original sense of physis as presence — as the happening of being — was already obscured when Aristotle turned it into a technical category in natural philosophy.

Similarly, logos — usually translated as "reason", "word", or "discourse" — names for Heraclitus not a faculty of the human mind but the gathering structure of being itself: the way in which the diverse and contradictory aspects of reality are held together in a unity that underlies their opposition. The human capacity for language and reason is a participation in this larger logos, not its origin. When logos becomes the ratio of the Scholastics, or the Reason of the Idealists, or the logic of the modern sciences, the original sense — being as gathering, as letting-appear — has been covered over.

The Greek word for truth, aletheia, is formed from the privative "a-" and lethe, forgetting or concealment. Truth is not agreement between a proposition and a fact but the happening of unconcealment — the event in which beings step out of hiddenness into the open. This makes truth primordially connected to the happening of being: things are, in the Greek sense, only insofar as they stand in the open, unconcealed, present. The history of Western philosophy, for Heidegger, is the progressive closure of this understanding — truth becoming correctness, logos becoming logic, physis becoming nature — until nothing remains of the original experience but technical concepts.

Heidegger's readings of Parmenides, Heraclitus, and Anaximander in Introduction to Metaphysics and in the later essay collections are among the most influential — and most contested — in twentieth-century classical scholarship. His claim to recover an "original" Greek experience has been criticised as romantic projection; his defenders argue he is doing genuine philosophy through the texts rather than philology.