In the opening mishnah of Tractate Kiddushin, we learned that a woman can be betrothed to a man with money, a document or sexual intercourse. The mishnah introduced this list by first telling us that it is about to list three ways that betrothal can take place, which in turn leads the Gemara to ask this question:
What does the number in the first clause of the mishnah come to exclude?
The Gemara assumes that by emphasizing that there are three effective legal pathways to betrothal, the mishnah is ruling something else out — a fourth, ineffective way. And the Gemara wants to know what that is.
The number in the first clause serves to exclude a wedding canopy.
Although it seems safe to assume that a couple entering under a huppah (marriage canopy) has agreed to wed, doing so is not in itself a valid path for betrothal. And the Gemara suggests this is what that mishnah wants to rule out when it specifies that there are only three ways to become betrothed.
This response seems to suffice for everyone except for Rav Huna. As we’ll learn on page 5a, Rav Huna holds that entering under a wedding canopy is actually an acceptable way to get betrothed. As we’ll see, he derives his position through a kal v’chomer (a fortiori) inference. So Rav Huna holds there are actually four ways to get engaged — the three ways listed in the mishnah, and a fourth derived logically. But this doesn’t solve the problem of the mishnah’s construction, which the Gemara still maintains is implying that something is excluded from the list of betrothal methods. So if we hold by Rav Huna’s position, there must be something else — a fifth way that the mishnah wants to exclude. And the Gemara suggests:
To exclude symbolic exchange.
Symbolic exchange refers to an exchange of items that have no real value. Betrothal can be effected through money, which does have value. But if the exchange is only something of symbolic (as opposed to actual) value, it is not a valid betrothal. Why would the mishnah need to rule this out? Because as we learned on yesterday’s daf, the ability to use money as a means of betrothal is derived from the fact that the biblical verse that mentions betrothal (Deuteronomy 24:1) shares language with the verse that talks aboutAbraham’s purchase of the field containing the Cave of Machpelah (Genesis 23:13). So someone might then imagine that just as a field can be acquired by a symbolic exchange, so too can a bride. But that is not the case.
It’s not out of the ordinary for the Mishnah to begin a discussion about a new topic the way it does in Kiddushin, by first telling us the number of items that will appear on a list it’s about to present (see Shabbat 1:1 or Bava Kama 1:1). It’s hard to imagine that, in each of these instances, the editors were trying to tell us that there is a specific additional item they were trying to rule out. It’s more likely they were trying to rule out all other ways.
But the Gemara assumes that something else is going on here and, in its own unique way, sets out to uncover what that is.
Read all of Kiddushin 3 on Sefaria.