Which is probably one of the most misunderstood citations in philosophy. It's the presence of other people that makes one acutely aware of oneself (since you are an object in the conscience of others).
From L'Être et le Néant:
But the Other is the indispensable mediator between myself and me. I am ashamed of myself as I appear to the Other.
In this dance is you-Daniel, me-Che, and Other, of which I will never know.
He did not say that, it's what one character says in Huis Clos. That's just like saying Tyrion is actually expressing what George Martin thinks.
Yes but it was a reference to his other ideas and so not really limited to the one character in one play.