Plato, too, knew the “underground”, but her called it a “cave” and created his splendid world-famous myth in which men were likened to prisoners in a… - Lev Shestov

Suppose Euripides is right, and that indeed no one can be sure whether life is not death and death life; can this truth ever become certain? If all men daily repeated Euripides’ words when they got up and when they went to bed, they would remain as strange and as problematic as on the day when the poet first heard them in the depths of his soul. P. 6

The Diary of a Madman is in a sense the key to Tolstoy's work. If it had not been written by Tolstoy himself, we should certainly have looked upon it as a calumny, since we are accustomed to look upon great men as the incarnation of all the civil and even the military virtues. p. 87

What happens to the mind of the underground man has no resemblance at all to thinking, nor even to seeking. He does not think, he excites himself desperately, throws himself about, knocks his head against the wall. He inflames himself the whole time, dashing up to unknown heights of fury, to fling himself into God knows what abysses of despair. He has no control of himself; a force far greater than himself has him completely under its sway. P. 42