nothing ≠ something...

Although traditional learning focusses on what is, Heidegger noted, it may be far more illuminating to examine the boundaries of ordinary knowledge by trying to study what is not.

What is Nothing, anyway?

It's not anything, and it's not something, yet it isn't the negation of something, either. Traditional logic is no help, since it merely regards all negation as derivative from something positive. So, Heidegger proposed, we must abandon logic in order to explore the character of Nothing as the background out of which everything emerges.

Carefully contemplating Nothing in itself, we begin to notice the importance and vitality of our own moods. Above all else, Nothing is what produces in us a feeling of dread {Ger. Angst}. This deep feeling of dread, Heidegger held, is the most fundamental human clue to the nature and reality of Nothing.
Heidegger: Being-There (or Nothing)

angst ...?