What, then, is truth? A mobile army of metaphors, metonyms, and
anthropomorphisms - in short, a sum of human relations which have been
enhanced, transposed, and embellished poetically and rhetorically, and
which after long use seem firm, canonical, and obligatory to a people:
truths are illusions about which one has forgotten that this is what
they are; metaphors which are worn out and without sensuous power; coins
which have lost their pictures and now matter only as metal, no longer
as coins.
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(Nietzsche, On Truth and Lie in an Extra-Moral Sense, 1873)