Civility costs nothing means that politeness and kindness take little from you but give much.
No, it is just a saying or proverb. It originates from the old UK and is a rephrase of the saying, "Promises cost nothing".
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it is actually saying that courtesy cannot be paid. It can only be made by you. It costs you nothing to be polite -- therefore, why should you be rude?
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Nothing it costs nothing at all
it costs nothing
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