 The Debtor’s Paradox. The ancient playwright Epicharmus tells the tale of a poor but resourceful debtor. When approached for payment, the man responds with a riddle. If you add a pebble to a collection of pebbles, you no longer have the same number. If you add a length to a cubit, you no longer have the same measure. In the same way, if you add a bit of matter to an existing portion of matter, you no longer have the same entity. Since man is nothing more than a material object whose matter is constantly changing, we do not survive from one moment to the next. The debtor concludes that he is not the same person who incurred the debt, so he cannot be held responsible for the payment. The exasperated creditor then strikes the debtor, who protests the abusive treatment. The creditor expresses sympathy, but points out that he cannot be held accountable for the assault. After all, material change has already taken place so, by the debtor’s own line of reasoning, the guilty party is no longer present. The scene is intended to be comedic, but the argument is no laughing matter. The man who incurred the debt was constituted by one portion of matter, M1. The man who is approached for payment is constituted by a distinct portion of matter, M2 (let us assume, for the sake of argument, that M2 consists of M1, together with some new matter). If constitution is identity, then the debtor’s reasoning is sound: the man approached for payment is not the man who incurred the debt. More generally, this version of the argument would show that it is impossible for material objects to survive the addition of any new parts. (Note: the claim that constitution is identity should not be confused with the thesis of “composition as identity”. On the latter view, see Section 8 of the entry on  identity.)