More Discussions for this daf
1. Man and Animal 2. Mechitzas Established on Shabbos 3. Mechitzah Shel Bnei Adam
4. Mechitzah for the third wall of the Sukah 5. Shavas b'Me'arah 6. A Human used as a Temporary Wall
7. What Happened to the Hukaf 8. מחיצה של בני אדם
DAF DISCUSSIONS - ERUVIN 44

moshe rubin asked:

Rava use the mechiza shel sadam to carry the flasks home and the gemoroh says that he could only do this once because after that it was l'da'as.

Question: mm'n. Either they saw him or they didn't. If they did, it was eitehr mares ayin or they chopped right away and it was l'da'as even then. If they didn't see, then it was not l'da'as the next time either.

moshe rubin, bklyn, ny

The Kollel replies:

Moshe, that is a very good question which touches upon some fascinating points regarding the laws of Mechitzah Shel Bnei Adam. There is much to discuss on this issue, so I will record the answer as briefly as possible in English, and I will attach a Hebrew .pdf file with a lengthier in-depth discussion of the issues upon request. (I also discussed this at length in my audio/video Shiur on Daf 44, which you can access along with the rest of our D.A.F. archives.)

I found that the Vilna Gaon addresses your question in two of his glosses on the Shulchan Aruch, in consecutive Se'ifim (OC 362:5,6), and suggests two different approaches to the issue. In one gloss (Se'if 6) he takes the approach that the people in Rava's Mechitzah did become aware that they were acting as a Mechitzah even during his initial usage of their Mechitzah. Nevertheless, the Halachah dictates that once a person has become a Mechitzah unwittingly, he may continue to act as a Mechitzah even after he becomes aware that he is being used as a Mechitzah (until the Mechitzah is "dismantled").

In the other gloss, the Vilna Gaon (based on the words of Maharam Rotenberg, cited in the Mordechai) explains that although the people who served as Rava's Mechitzah were not made aware that they were serving as a Mechitzah, nevertheless, it was prohibited for Rava to use them again as his Mechitzah. Since they served once as his Mechitzah, if Rava were to use them again there would be a greater likelihood that they will discover his true purpose before the Mechitzah is completed, making it a Mechitzah Shel Bnei Adam l'Da'as which is prohibited.

Best wishes,

Mordecai Kornfeld