"It is highly convenient to believe in the infinite mercy of God when you feel the need of mercy, but remember also his infinite justice."

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Absolute space, that is to say, the mark to which it would be necessary to refer the earth to know whether it really moves, has no objective existence.... The two propositions: "The earth turns round" and "it is more convenient to suppose the earth turns round" have the same meaning; there is nothing more in the one than in the other.

— Henri Poincare