The Fourth Directive [208-209]

b) The fourth directive: the open as the primordial essence of unconcealedness. Reference to Being and Time and Sophocles, Αἴας V, 646f. Time as letting appear and concealing. Reference to Holderlin. Time as "factor" in the modern period. The upsurge of the open into unconcealedness. The "identification" of openness and freedom. Ἀλήθεια as the open of the clearing.

We shall conclude our elucidation of the essence of ἀλήθεια by attempting to follow a fourth directive provided by the translation of ἀλήθεια as "unconcealedness."

Thinking ahead. we can say that the open holds sway in the essence of unconcealedness. The word "open" makes us think first of what is not closed off, hence is dis-closed. Thought in this way the open proves to be a consequence of an opening up and a disclosing. For now, let us leave undecided whether or not the open must be the essential ground of disclosedness, providing the possibility of unconcealedness in the first place, rather than merely being its result. Prior to all that, we need to see that the Greeks did in fact experience within the realm of the essence of ἀλήθεια something that made it necessary for them to speak in some way of the open. But nowhere among the Greeks do we find the essential concept of the open. On the contrary, we encounter in the essential domain of ἀλήθεια, and of the Greek thinking of Being, words and names referring only approximately to what we are calling the open.

A simple dictum from Greek poetry may testify to this. In addition, it will again provide us with an opportunity to think in a mysteriously simple way the essential unity of the fundamental Greek words, a unity we have more than once considered in the course of our meditation. The dictum names the relation between concealment and disclosure, appearance and emergence Thereby it immediately provides the directive that is to guide our present reflection. The dictum expresses simultaneously what could be called a foreword to the saying of the essence of Being.

The dictum deals with "time " In Being and Time, time is experienced and named as fore-word for the word "of" Being. The Greek dictum on time occurs in Sophocles' tragedy Αἴας. (V. 646f.), and is as follows

ἅπανθ᾽ ὁ μακρὸς κἀναρίθμητος χρόνος
φύει τ᾽ ἄδηλα καὶ φανέντα κρύπτεται

"The broad, incalculable sweep of time lets emerge everything that is not open as well as concealing (again) in itself what has appeared "

Let us consider this dictum starting from the end The last word is κρύπτεται. Κρύπτεσθαι means to take back into oneself. to hide back

Martin Heidegger (GA 54) Parmenides