 The indeterminacy of translation applies to one’s own language. Introspection will not settle whether \(x\) is the same person as \(y\) means \(x\) has the same body as \(y\) or \(x\) has same memories as \(y\). You have never encountered a case in which these two possible rules of usage diverge.  John Locke imagines a prince and cobbler who awake with each other’s memories. Is the prince now in the cobbler’s bed or is the prince in his royal bed with errant memories? Quine sees a deflating resemblance with the decapitation riddle. Either of the incompatible answers fits past usage. Yet Locke answers that the prince and cobbler have switched bodies. Materialists counter that the prince and cobbler have instead switched psychologies. Locke and his adversary should have instead shrugged their shoulders.