The groundlessness of idle talk is no obstacle to its becoming public; instead it encourages this. Idle talk is the possibility of understanding everything without previously making the thing one's own. If this were done, idle talk would founder; and it already guards against such a danger. Idle talk is something which anyone can rake up; it not only releases one from the task of genuinely understanding, but develops an undifferentiated kind of intelligibility, for which nothing is closed off any longer.
Discourse, which belongs to the essential state of Dasein's Being and has a share in constituting Dasein's disclosedness, has the possibility of becoming idle talk. And when it does so, it serves not so much to keep Being-in-the-world open for us in an articulated understanding, as rather to close it off, and cover up the entities within-the-world. To do this, one need not aim to deceive. Idle talk does not have the kind of Being which belongs to consciously passing off something as something else. The fact that something has been said groundlessly, and then gets passed along in further retelling, amounts to perverting the act of disclosing [Erchliessen] into an act of closing off [Verschliessen]. For what is said is always understood proximally as 'saying' something-that is, an uncovering something. Thus, by its very nature, idle talk is a closing-off, since to go back to the ground of what is talked about is something which it leaves undone.
This closing-off is aggravated afresh by the fact that an understanding of what is talked about is supposedly reached in idle talk. Because of this, idle talk discourages any new inquiry and any disputation, and in a peculiar way suppresses them and holds them back.
This way in which things have been interpreted in idle talk has already established itself in Dasein. There are many things with which we first become acquainted in this way, and there is not a little which never gets beyond such an average understanding. This everyday way in which things have been interpreted is one into which Dasein has grown in the first instance, with never a possibility of extrication. In it, out of it, and against it, all genuine understanding, interpreting, and communicating, all re-discovering and appropriating anew, are performed. In no case is a Dasein, untouched and unseduced by this way in which things have been interpreted, set before the open country of a 'world-in-itself, so that it just beholds what it encounters. The dominance of the public way in which things have been interpreted has already been decisive even for the possibilities of having a mood—that is, for the basic way in which Dasein [170] lets the world "matter" to it.1 The "they" prescribes one's state-of-mind, and determines what and how one 'sees'.
1 '... über die Möglichkeiten des Gestimmtseins entschieden, das heisst über die Grundart, in der sich das Dasein von der Welt angehen lässt.' The second 'über' is found only in the later editions.