Eruvin 72B

מיתיבי, אמר רבי יהודה הסבר: לא נחלקו בית שמאי ובית הלל על מחיצות המגיעות לתקרה שצריכין עירוב לכל חבורה וחבורה. על מה נחלקו ⁠— על מחיצות שאין מגיעות לתקרה, שבית שמאי אומרים: עירוב לכל חבורה וחבורה, ובית הלל אומרים: עירוב אחד לכולן.

The Talmud raises an objection based on the following baraita: R' Yehuda the Keen [hasabbar], who was known by this name due to his sharp mind, said: Beit Shammai and Beit Hillel did not disagree about partitions that reach the ceiling, as all agree that they require a separate contribution to the eiruv for each and every group. With regard to what did they disagree? With regard to partitions that do not reach the ceiling, as Beit Shammai say: A separate contribution to the eiruv is required for each and every group, and Beit Hillel say: One contribution to the eiruv suffices for all of them.

למאן דאמר במחיצות המגיעות לתקרה מחלוקת ⁠— תיובתא, ולמאן דאמר במחיצות שאין מגיעות לתקרה מחלוקת ⁠— סייעתא. להך לישנא דאמר רב נחמן: מחלוקת במסיפס ⁠— תיובתא.

According to the one who said that it was with regard to partitions that reach the ceiling that there was a dispute, this baraita offers a conclusive refutation. And according to the one who said that it was with regard to partitions that do not reach the ceiling that there was a dispute, the baraita offers support. With regard to that version which holds that Rav Naḥman said: The dispute applies only where they divided the hall with a mesifas, this baraita is a conclusive refutation.

להך לישנא דאמר רב נחמן: אף במסיפס מחלוקת, לימא תהוי תיובתא?

However, the following issue needs further clarification: With regard to that version which holds that Rav Naḥman said: The dispute applies even where the hall was divided with a mesifas, should we say that R' Yehuda the Keen’s statement is a conclusive refutation? That is to say, does it imply that all agree that in the case of a mesifas, one eiruv suffices for them all?