The original ship of Theseus is a philosophy problem that dates back to (at least) Plutarch. The wooden ship is preserved by virtue of gradually replacing each part as it decays until eventually all the original parts have been replaced.
Is it the same ship?
But now suppose that you also saved all the original parts and reassembled them into a ship.
Which is the real ship of Theseus?
Problems of identity are vexing. What really makes a thing that thing? Where’s the line between a fictionalized autobiography and a biography full of fictions? Why is David Copperfield fiction and Fire and Fury nonfiction?
Maybe there’s no one thing that counts as defining people or genres. Maybe it’s just a Wittgensteinian family resemblance—some set of overlapping traits—that makes a thing what it is.
And yet for all Wittgenstein’s clever thought experiments, we still know a chair when we see one.