Being-in-itself is full positivity, excluding all negation, becoming, and temporality.

Evidence

The result is evidently that being is isolated in its being and that it does not enter into any connection with what is not itself. Transition, becoming, anything which permits us to say that being is not yet what it will be and that it is already what it is not—all that is forbidden on principle. For being is the being of becoming and due to this fact it is beyond becoming. It is what it is. This means that by itself it can not even be what it is not; we have seen indeed that it can encompass no negation. It is full positivity. It knows no otherness; it never posits itself as other-than-another-being. It can support no connection with the other. It is itself indefinitely and it exhausts itself in being. From this point of view we shall see later that it is not subject to temporality. It is, and when it gives way, one can not even say that it no longer is. Or, at least, a consciousness can be conscious of it as no longer being, precisely because consciousness is temporal. But being itself does not exist as a lack there where it was; the full positivity of being is re-formed on its giving way. It was and at present other beings are: that is all. — Jean-Paul Sartre, Being and Nothingness, 165

Categorization

• DEFINE: Defines being-in-itself as absolute positivity with no negation, no becoming, no temporality — a core ontological term.
• BMF: The in-itself’s full positivity that cannot even lack or not-be evokes the for-itself’s negation-based being that will be described later in We’s and other fiction — but more directly, the ‘being that knows no otherness’ resonates with the frozen, self-identical society of Zamyatin’s We vs. the negating individual.
• XREF: connects to: Appearance is full positivity, exactly equal to the being of the existent — Jean-Paul Sartre, Being and Nothingness: An Essay on…, 114; Being-in-itself is a solid, self-sealed mass without interiority.; The in-itself is fully self-coincident, leaving no gap for nothingness — Jean-Paul Sartre, Being and Nothingness: An Essay on…, 328 (+3 more)

Broader Connections

• The in-itself is fully self-coincident, leaving no gap for nothingness #corroborates (0.92) — Jean-Paul Sartre, Being and Nothingness, 328
• Being-in-itself is a solid, self-sealed mass without interiority. #expands (0.85)
• The For-itself derives all its powers precisely from not being Being #corroborates (0.82)
• Non-being has transphenomenal objectivity just as being does. #complicates (0.78)
• The body’s immobility as surpassed facticity is the pure in-itself #qualifies (0.72) — Jean-Paul Sartre, Being and Nothingness, 906