"He is ungrateful who denies that he has received a kindness which has been bestowed upon him; he is ungrateful who conceals it; he is ungrateful who makes no return for it; most ungrateful of all is he who forgets it."

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If we were all given by magic the power to read each other’s thoughts, I suppose the first effect would be almost all friendships would be dissolved; the second effect, however, might be excellent, for a world without any friends would be felt to be intolerable, and we should learn to like each other without needing a veil of illusion to conceal from ourselves that we did not think each other absolutely perfect.

— Bertrand Russell