The Debtor’s Paradox

Πάντα ῥεῖ (Panta rei), everything is in flux, so Heraclitus. Therefore, you can’t step into the same river twice, he said. But is really everything in flux? Also your body? According to Epicharmus of Kos “Yes, indeed”. Epicharmus was a Greek dramatist and philosopher who lived about 500 B.C. He is said to have been the first to apply Heraclitus’s idea to the human body, which he did in one of his comedies. However, most of his work has been lost. Only fragments remain. So we know his “bodily version” of Heraclitus’s idea only from how others have reproduced it. It has become known as the Debtor’s Paradox.

Before telling how it runs, I must say a few words about the Growing Argument, which has also been introduced by the Old Greek. Say you show me a heap of pebbles and you take one pebble away. You ask me: “Has the heap remained the same?” “No, of course not”, I reply. Then you put back the pebble and add yet another one. You ask me: “Has the heap remained the same this time?” And again I reply “No, of course not”. Then you say: “One man grows and another shrinks, and so we change all the time. Never we are the same as we were just before and never we’ll be the same again”.

One year later I urgently need money and I call you up and ask you whether you can lend me thousand euros. “Of course, I can”, you say, “I am always prepared to help a friend. However, there is one condition: You must pay it back to me before the end of the year.” “All right”, I say “I’ll certainly do.” The next day I go to your home, sign a contract and receive thousand euros from you.

Next January I meet you on a New Year’s Party. “You still haven’t paid back the money!”, you reproach me.” “Why should I pay you money?” I return, “I don’t owe you any money.” After some quarrelling I say: “Oh, now I understand what you mean. You lent the money to a kind of lookalike of me. But don’t you remember the Growing Argument that you explained to my lookalike? And that you ended the explanation with the statement: We change all the time. Never we are the same as we were just before and never we’ll be the same again? That lookalike has changed into me, but it isn’t me. So I owe you nothing.”

Thus runs the Debtor’s Paradox (in my version). How did the story continue? I didn’t pay and it came to a court case. The judge asked me to show my identity card, she saw that the same card number was also written in the contract and concluded that it was I who had signed the contract, so that it was I who had to pay.

The upshot is that I am not my body, if we see a body as a fixed lump of matter. However, we are our body if we realize that it is a clustered lump of material characteristics. The composition of the lump may change but the cluster of material characteristics remains relatively stable, not counting the fact that we have also mental characteristics (and according to some identity philosophers it’s only the mental characteristics that are essential). So you can step into the same river twice, for the river is the flow and not the molecules.

P.S. Any agreement with the so-called “Ship of Theseus Paradox” is not a coincidence

Writing this blog I have been inspired by:

- Vincent Descombes, Puzzling Identities. Cambridge, Mass.: Harvard University Press, 2016; pp. 43 ff.

- “The Debtor’s Paradox”, on website http://metaphysicist.com/puzzles/debtor/