“If the madman could for an instant become careless, he would become sane. Every one who has had the misfortune to talk with people in the heart or on the edge of mental disorder, knows that their most sinister quality is a horrible clarity of detail; a connecting of one thing with another in a map more elaborate than a maze. If you argue with a madman, it is extremely probable that you will get the worst of it; for in many ways his mind moves all the quicker for not being delayed by the things that go with good judgment. He is not hampered by a sense of humour or by charity, or by the dumb certainties of experience. He is the more logical for losing certain sane affections. Indeed, the common phrase for insanity is in this respect a misleading one. The madman is not the man who has lost his reason. The madman is the man who has lost everything except his reason.”
Orthodoxy, G.K. Chesterton
Henry IV: Look here, doctor! I remember a priest, certainly Irish, a nice-looking priest, who was sleeping in the Sun one November day, with his arm on the corner of the bench of a public garden. He was lost in the golden delight of the mild sunny air which must have seemed for him almost summery. One may be sure in that moment he did not know any more that he was a priest, or even where he was. He was dreaming… A little boy passed with a flower in his hand. He touched the priest with it here on the neck. I saw him open his laughing eyes, while all his mouth smiled with the beauty of his dream. He was forgetful of everything… But all at once, he pulled himself together, and stretched out his priest’s cassock; and there came back to his eyes the same seriousness which you have seen in mine; because the Irish priests defend the seriousness of their Catholic faith with the same zeal with which I defend the secret rights of the heredity monarch! I am cured gentlemen: because I can act the mad man to perfection, here; and I do it very quietly, I’m only sorry for you that have to live your madness so agitatedly, without knowing it or seeing it.
Henry IV, Luigi Pirandello