Thomas Sheehan on the turn within Ereignis.

The clue to understanding the proper and basic sense of the Kehre lies in the German term with which Heidegger glosses Ereignis, namely, Gegenschwung: back-and-forth reciprocity. (The word “reciprocity” comes from the Latin reci-proci-tas, back-and-forth-ness.) The “turn” in its proper sense refers to the back-and-forth relation of need between man and meaning-giving: man needs meaning as much as meaning needs man. More specifically, the back-and-forth-ness refers to the two forms of the reciprocal need of man and meaning-giving: man’s passive submission to being appropriated to the meaning-process (Brauch) and man’s active sustaining of that process (Zugehören). The following table illustrates the reciprocal need of man for meaning and of meaning for man. It also illustrates (by way of the dots) the tension or Streit between passive thrownness/appropriation and active projection/sustaining of the meaning process.

Thus the answer to Heidegger’s basic question “How does meaning occur at all?” is: It happens because man is “passively” thrown into (appropriated to, or needed for) “actively” sustaining the meaning-process. In a word: Ereignis as reciprocity.

Pp. 59-60