Jean-Paul Sartre:

GARCIN: Will night never come?

INEZ: Never.

GARCIN: You will always see me?

INEZ: Always.

GARCIN: This bronze. Yes, now’s the moment; I’m looking at this thing on the mantelpiece, and I understand that I’m in hell. I tell you, everything’s been thought out beforehand. They knew I’d stand at the fireplace stroking this thing of bronze, with all those eyes intent on me. Devouring me. What? Only two of you? I thought there were more; many more. So this is hell. I’d never have believed it. You remember all we were told about the torture-chambers, the fire and brimstone, the “burning marl.” Old wives’ tales! There’s no need for red-hot pokers. Hell is — other people!

(No Exit (Huis Clos), 1944)

T.S. Eliot:

There was a door
And I could not open it. I could not touch the handle.
Why could I not walk out of my prison?

What is hell? Hell is oneself,
Hell is alone, the other figures in it
Merely projections. There is nothing to escape from
And nothing to Escape to. One is always alone.

(The Cocktail Party, 1949)