For, believe me, the secret of the greatest fruitfulness and the greatest enjoyment of existence is: to live dangerously!
He who fights with monsters should look to it that he himself does not become a monster. And when you gaze long into an abyss the abyss also gazes into you.
The anthropological criminologists tell us that the typical criminal is ugly: monstrum in fronte, monstrum in animo [monstrous in appearance, monstrous in spirit].
One begins to distrust very clever persons when they become embarrassed.
He who considers more deeply knows that, whatever his acts and judgements may be, he is always wrong.
Life is that which must overcome itself again and again.