21 Beitzah 12a

One Sage, Beit Shammai, holds that we issue a decree and prohibit a hinge in the middle due to a hinge on the side; and one Sage, Beit Hillel, holds that we do not issue this decree. Since placing a hinge of this type does not constitute the prohibited labor of building, it is permitted. MISHNA: Beit Shammai say: One may carry out on a Festival neither a minor child, nor a lulav, nor a Torah Scroll into the public domain, as none of these are required for the preparation of food; and Beit Hillel permit it. GEMARA: The tanna who reviews mishnayot teaches a baraita before Rav Yitzḥak bar Avdimi: One who slaughters a gift offering on a Festival is flogged for transgressing the prohibition: “No manner of work shall be done on them” (Exodus 12:16). Since this slaughtering was not performed for the purpose of eating, the action constitutes a prohibited labor on a Festival. Rav Yitzḥak bar Avdimi said to that tanna: Who could have said this baraita to you? It is evidently in accordance with the opinion of Beit Shammai, who say that we do not say: Since carrying out was permitted on a Festival for the purpose of food preparation, it was also permitted not for that purpose. For if you say the baraita is accordance with the opinion of Beit Hillel, they say: Since carrying out was permitted for the requirements of food preparation, it was also permitted not for these requirements. Here, too, with regard to the prohibited labor of slaughtering, since slaughter was permitted for the requirements of food preparation, it was also permitted not for these requirements. It was permitted for any purpose that benefits people, whether directly or indirectly. Rabba strongly objects to this reasoning: From where do you infer that Beit Shammai and Beit Hillel disagree over this issue? Perhaps they disagree about the following: The halakhot of eiruv and the prohibition against carrying out apply to Shabbat, but there are no halakhot of eiruv nor a prohibition against carrying out on a Festival. The Gemara clarifies the dispute according to this explanation: One Sage, Beit Shammai, holds that the halakhot of eiruv and the prohibition against carrying out apply to Shabbat, and similarly the halakhot of eiruv and carrying out apply to a Festival. The only difference is that, on a Festival, carrying, like other types of prohibited labor, is permitted for the sake of food preparation. And one Sage, Beit Hillel, holds that the halakhot of eiruv and the prohibition against carrying out apply to Shabbat, but there are no halakhot of eiruv nor a prohibition against carrying out on a Festival, as it is written: “Neither carry forth a burden out of your houses on the Shabbat day” (Jeremiah 17:22), from which Beit Hillel inferred: On Shabbat, yes, carrying from one domain to another is indeed prohibited; on a Festival, no, it is not prohibited. According to this explanation, Beit Shammai and Beit Hillel did not disagree about whether a prohibited labor that is permitted for the purpose of food preparation on a Festival is also permitted when it does not serve that purpose. Rav Yosef strongly objects to this explanation of Rabba: However, if that is so, that the dispute is whether the prohibition against carrying out applies on a Festival, Beit Hillel should permit one to move muktze objects, as the prohibition of handling muktze is an extension of the prohibition against carrying out. Consequently, let them differ with regard to whether or not it is permitted to carry out stones on a Festival. Rather, from the fact that Beit Shammai and Beit Hillel do not disagree with regard to stones but concerning objects that serve some sort of purpose, conclude from this: Everyone agrees that carrying out is prohibited on a Festival, and the Torah permitted it only when it is necessary for sustenance. Instead, Beit Shammai and Beit Hillel disagree with regard to carrying out that is not for the purpose of food preparation. According to the opinion of Beit Hillel, since carrying out is permitted for the sake of sustenance, it is entirely permitted. According to Beit Shammai, the Sages permitted only labor that serves the purpose of food preparation. The Gemara comments: And Rabbi Yoḥanan also holds that Beit Shammai and Beit Hillel disagree with regard to the principle: Since carrying out is permitted on a Festival for the purpose of food preparation, it was also permitted not for this purpose, as the tanna teaches a baraita before Rabbi Yoḥanan: One who cooks the sciatic nerve in milk on a Festival and eats it is flogged for violating five distinct prohibitions. How so? (1) He is flogged due to the prohibition of cooking the sciatic nerve, which is prohibited because the sciatic nerve is unfit for consumption; (2) and he is flogged due to the prohibition of eating the sciatic nerve, which is explicitly prohibited by the Torah; (3) and he is flogged due to the prohibition of cooking meat in milk; (4) and he is flogged due to the prohibition of eating meat cooked in milk; (5) and lastly, he is flogged