Makkot 3a, continued:
Last week we spent the entire time on a single mishnah and the two lines of Gemara that belong to it. ALG reports that her friend called it the hardest mishnah in Sha"s, and that the problem with it is that it doesn't make any sense. This may explain why the rishonim go so crazy about it -- they're groping around in the dark trying to figure out what it means, and tripping over each other.
The basic premise seems reasonable. We're continuing with a list of cases where the eidim zomemin don't actually pay the penalty that would have been imposed on the person being testified against. Suppose Homer testifies that Kirk divorced his wife Luann and didn't pay her the amount of her ketubah (severance pay), let's say 200 zuz, and then Homer's testimony is invalidated. It wouldn't make sense to make Homer pay 200 zuz, because Homer wouldn't actually have cost Kirk 200 zuz -- if indeed Kirk didn't divorce Luann just now, he would have eventually had to pay her ketubah at some point down the line anyway. So what loss would Homer actually have imposed on Kirk (and thus, what does Homer have to pay)? If you, like me, thought the issue was about the time value of money, and the question of whether Kirk would have to pay now or later, then you would be wrong, but it would have taken you a long time to realize the error of your ways. (The next mishnah apparently is about the time value of money, though.) Really, it's more like insurance or gambling or the futures market -- the current price of the ketubah is decreased because there is a probability that it will eventually be worth its face value, and a probability that it will be worth nothing. So the current value of the ketubah represents the expectation value of how it will eventually turn out, with some adjustment for risk. (Or something like that -- I'm speaking as a physicist, not an economist, so I'm sure I'm using the wrong terminology.) There is some chance that Kirk will divorce Luann or die first, so Kirk (or his estate) will owe 200 zuz, and there's also a chance that Luann will die first, so Kirk owes her nothing and gets to keep whatever assets he had set aside for the ketubah. Thus, the actual value of the ketubah is somewhere between 0 and 200 (depending on these probabilities and other things), and thus that's what Homer has to pay Kirk.
That's the Mishnah. The Gemara then asks "How is this calculated?". A fair question. Three amoraim give three different answers: 1) with the husband, 2) with the wife, 3) with the wife and her ketubah. And that's all the Gemara on this Mishnah.
Well, that was perfectly clear to me!!!
Wait, no it wasn't. And the rishonim don't think so either. I confess that we didn't do an exhaustive survey of the guys in the back, but we spent a lot of time on Rashi, glanced at Tosafot (which is usually scary, but gives examples with numbers this time), and read the Rambam.
Rashi frames the situation like this: both the husband and the wife have a potential claim. The wife's claim is (the value of the ketubah) * (the probability that the husband will die first or divorce her); call this w. The husband's claim is (the value of the assets set aside for the ketubah) * (the probability that the wife will die first); call this h. So the machloket in the Gemara is about which of these is used to calculate what Homer owes in the Mishnah: does he pay h (since he would have prevented Kirk from possibly collecting this), or does he pay w (for reasons I don't quite understand, and I don't think Rashi does either), or does he pay 200 zuz minus w (since he would have made Kirk definitely pay 200 zuz instead of just maybe)? I think that's the idea -- I might still have it completely wrong. (And I don't see why it shouldn't involve some combination of h and w, but what do I know.)
Rambam (Hilchot Eidut 21:1) goes with the third opinion (the wife and her ketubah) and understands this to mean that the wife herself (i.e. the actual persn) is used to calculate the amount. For example, if the wife is old or sick, or the couple gets along well, then it's less likely that she'll collect her ketubah (since she'll die before he dies or divorces her), so the value goes down. But if she's young or healthy, or the couple is in conflict, then it's more likely that she'll collect (since he'll die or divorce her before she dies), so the value goes up.
Let me know if this understanding is totally wrong.