"To exist (in mathematics), said Henri Poincaré, is to be free from contradiction. But mere existence does not guarantee survival. To survive in mathematics requires a kind of vitality that cannot be described in purely logical terms."

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There is yet another kind of matrimonial dialect (which naturally succeeds this of talking at each other), which may very properlybe styled The Language Contradictory.... In the former, however plain the object of satire may be exhibited to the whole company, yet there always remains some little covering.... But in this last method, the defiance becomes more open and the impetuosity with which these contradictions are uttered (although the subjects of them are often of the most indifferent nature) evidently prove that they arise from passion.

— Sarah Fielding