Q&A: Betrothal of One of Two Sisters
Betrothal of One of Two Sisters
Question
Hello Rabbi,
I would be glad to hear your view on the matter of betrothing one of two sisters, where Abaye and Rava disagree whether betrothal that is not fit for intercourse counts as valid betrothal. At the basis of the dispute, it seems that this betrothal takes effect because of doubt, and they only disagree over whether the rule of betrothal that is not fit for intercourse cancels it. The question then arises: how can the betrothal take effect when you do not know, and cannot know, who exactly is betrothed? There is no real doubt in reality here, and the very act of the betrothal taking effect seems to "create a doubt" without that doubt having any grip on reality itself. (Certainly the betrothal does not take effect randomly on one of them and you just do not know which one.) Is there anything similar to this anywhere else?
Answer
Discussion on Answer
These things are explained in more detail in volume 12 of the Talmudic Logic series. Chapter 3 deals with betrothal that is not fit for intercourse. The book can only be bought on Amazon (and perhaps it is in the Bar-Ilan library).
In the case of two sisters together, these are two different acts of betrothal done simultaneously, and each one by itself is an act that permits and not one that forbids. The prohibition regarding one is a result of the betrothal of the other, and not of her own betrothal itself. By contrast, in the case of one out of two, the prohibition regarding each one is the result of her own act of betrothal itself (together with the other), and therefore it is an act that forbids.
Nice, I enjoyed it מאוד. I thought it might be related to quantum doubt, but my knowledge in that area is very limited, so I did not want to just say it casually—that is why I asked here. If there is such a connection, I would be happy for a reference to some study material through which one could learn the logic of quantum doubt and the concept of collapse that you mentioned.
In the lesson, as I understood it, you did not answer the question of why Abaye forbids the case of two sisters betrothed together, where the implication is that he requires an act of betrothal that permits and not one that forbids, as opposed to one of two sisters—where there too there is an act of betrothal that forbids (in "quantum doubt") and does not permit.