Study Beitzah folio 38A with parallel Hebrew-English text, traditional commentary, and modern study tools. Free access to Babylonian Talmud online.
Text Excerpt
והוינן בה: מאי שנא לכאן ולכאן דלא — דאין ברירה, מזרח ומערב נמי אין ברירה!
And we discussed the following difficulty with regard to this teaching of Ayo: What is different about the case where two rabbis are coming to the two locations, one here and the other there, and one places two eiruvin, planning to decide on Shabbat which lecture he will attend? Why did R' Yehuda state that this may not be done? It is because he held that there is no retroactive designation. But if so, in the first case as well, where only one rabbi comes, but the location of his lecture was not known before Shabbat, and one placed eiruvin in the east and the west, we should say that neither is effective because the rabbi’s location will not be known until Shabbat, and there is no retroactive designation.
ואמר רבי יוחנן: וכבר בא חכם. אלמא: לית ליה לרבי יוחנן ברירה!
And R' Yoḥanan said in explanation: This first case is referring to a situation in which the rabbi had already arrived before the eiruv was placed, but the one placing the eiruv does not know the rabbi’s location. Therefore, it had already been determined which of the two eiruvin would be effective, although it was not yet known to him when Shabbat began. Apparently, then, R' Yoḥanan does not accept the principle of retroactive designation even in matters of rabbinic law, as he states that if the rabbi were to arrive after the eiruv was placed, it would not be effective retroactively.
אלא: לעולם לא תיפוך, וכי לית ליה לרבי אושעיא ברירה — בדאורייתא, אבל בדרבנן — אית ליה.
Rather, the Talmud rejects this approach and states: Actually, do not reverse the views of R' Yoḥanan and R' Hoshaya; it is indeed R' Hoshaya, also known as R' Oshaya, who accepts retroactive designation, and R' Yoḥanan who rejects it. As for R' Oshaya’s statement with regard to the entrances to a house that contains a corpse, the following answer may be offered: And when does R' Oshaya not hold of the principle of retroactive designation? With regard to matters of Torah law, such as the ritual impurity of the dead. But with regard to matters of rabbinic law, such as Shabbat limits and the placement of eiruvin, he does accept this principle.