If you grew up in Italy, like I did, or visit often, you’ve got a jar full of Euro coins somewhere. You always forget to bring them with you on your next flight, so they pile up useless each time you come back with more. Friedrich Nietzsche once wrote that truth itself is like a bunch of coins (“a mobile army of metaphors, metonymies, anthropomorphisms”) so worn out that no one can tell what their “effaced obverse” was supposed to mean anymore.