Today’s daf asks the question: When is the principle of miggo operative?
First things first: What is miggo?
As we saw back on Ketubot 12, miggo is a talmudic principle that says that if a witness says something in court that, if it had been a lie, is less beneficial than it could have been, we believe the witness is telling the truth. Basically, we know that people lie, but we expect them to lie in ways that make them look best.
Let’s look at one of the examples discussed on today’s daf:
If people saw a woman speaking to one man, and they said to her: “What is the nature of this man?” And she said: “He is a man so-and-so and he is a priest.”
Rabban Gamliel and Rabbi Eliezer say: She is deemed credible, and Rabbi Yehoshua says: It is not from her mouth that we conduct our lives.
For context, “speaking” in this context is a euphemism, either for being alone with someone of the opposite sex (according to Ze’eiri) or for engaging in intercourse (according to Rav Asi). If a woman were accused of one of those things, the most beneficial thing she could say is that she hadn’t been “speaking” with the man at all. But that’s not what she says. Instead, she offers a different statement which partially implicates her in wrongdoing — by identifying the man and his lineage, she admits that she was “speaking” to him. If she was going to lie, she could have made up a much better lie — a miggo!
According to Rabban Gamaliel and Rabbi Eliezer, then, she is believed as to the man’s identity. But Rabbi Yehoshua disagrees. Rav Asi explains the reasoning: If she was caught red-handed, then she couldn’t have realistically denied that she had been “speaking” to the man. In that case, there was no more advantageous lie she could have told so this isn’t actually a case where miggo is operative.
Today’s daf explores a series of other cases where the miggo principle might apply: an unmarried woman who admits to being pregnant and identifies the father, and a woman who admits she has no hymen but argues that she had some kind of non-sexual accident which tore it (fun fact: most hymens don’t actually break or tear, but rather stretch and thin over time).
The last case it discusses is that of a woman who admits she has no hymen but discloses that she was sexually assaulted after her betrothal but before her marriage was consummated. In these cases, the Gemara’s interest is what kind of settlement she is owed by her husband in the case of divorce. The Gemara assumes that the man’s discovery of his new wife’s lack of hymen inevitably leads to the end of their marriage — and let’s be honest, a new bride whose husband takes her to court the morning after their marriage alleging fraud would probably agree.
Though the examples on today’s daf are ones where the witness is a woman, across the Talmud, miggo applies to both women and men. In all cases, however, the Talmud makes a pair of assumptions: first, people lie in court. And second, when people lie in court, they do so in order to achieve the best possible outcomes for themselves. So if someone partially incriminates themselves, or concedes to something socially taboo or pejorative, we should assume they are telling the truth. According to the rabbis, people may or may not be ethical, but those who are unethical are still rationally self-interested. Miggo!
Read all of Ketubot 16 on Sefaria.