The Gemara notes: And there is nothing more to discuss here. Clearly, the opinions of Rabbi Akiva and Rabbi Shimon do not necessarily coincide.

The baraita continues: If he grew the etrog in a mold and shaped it to appear like a different species, it is unfit. Rava said: The Sages taught that it is unfit only if he shaped it to appear like a different species; however, if he shaped the etrog so it still appears like its own species, it is fit. The Gemara asks: That is obvious; the phrase: Like a different species, is explicitly taught in the baraita. If it shaped like its own species, it is fit. The Gemara answers: No, Rava’s statement is necessary to deem fit an etrog that is shaped into the shape of many planks, i.e., pieces of wood attached to each other. Although its shape is not precisely that of a regular etrog, it sufficiently resembles a regular etrog and is fit.

§ It was stated that the amora’im disagree with regard to an etrog that mice pierced. Rav said: That is not beautiful. Is that so? But wouldn’t Rabbi Ḥanina dip his etrog, eat part of it, and fulfill his obligation with what remained of it? The Gemara asks: And for Rabbi Ḥanina, the mishna is difficult, as it states that an incomplete etrog is unfit.

The Gemara explains: Granted, for Rabbi Ḥanina, the mishna is not difficult, as it can be explained that here, when the mishna prohibits one from using an incomplete etrog, it is referring to performing the mitzva on the first day of the festival of Sukkot, when a complete taking of the species is required; and there, when Rabbi Ḥanina’s conduct leads to the conclusion that an incomplete etrog is fit, it is referring to performing the mitzva on the second day of the Festival or thereafter. However, according to Rav, who said an etrog that was pierced by mice is unfit, Rabbi Ḥanina’s conduct is difficult, as the requirement of beauty applies on all seven days. The Gemara answers: This is not difficult, as Rav could have said to you: Mice are different, as they are repulsive. When mice pierce an etrog, what remains is antithetical to beauty. When a person bites an etrog, what remains can still be considered beautiful.

§ Some say this exchange differently. Rav said with regard to an etrog that mice pierced: That is beautiful, as Rabbi Ḥanina would dip his etrog, eat part of it, and fulfill his obligation with what remained of it, indicating that an incomplete etrog is fit. The Gemara asks: And for Rabbi Ḥanina, the mishna is difficult, as it states that an incomplete etrog is unfit. The Gemara answers: The mishna is not difficult; here, it is referring to performing the mitzva on the first day of the festival of Sukkot; there, it is referring to performing the mitzva on the second day of the Festival or thereafter.

A dispute between Rabbi Meir and Rabbi Yehuda is cited in a mishna with regard to the minimum measure of a small etrog. Rafram bar Pappa said: Like the dispute here, so is the dispute with regard to the matter of rounded stones, as it was taught in a baraita: On Shabbat three rounded stones may be taken into the bathroom in order to clean oneself with them. Although generally one may not move stones on Shabbat because they are set aside from use, the Sages permitted doing so in the interest of human dignity. However, they disagreed, with regard to the size of these stones. And what is their measure? Rabbi Meir says: A walnut-bulk; Rabbi Yehuda says: An egg-bulk. Clearly the rationales for these disputes are different; however, since the respective measures are identical, the analogy can serve as a mnemonic.

The mishna continues: And in a large etrog, the maximum measure is so that one could hold two in his one hand; this is the statement of Rabbi Yehuda. Rabbi Yosei says: It is fit even if it is so large that he can hold only one in his two hands. It is taught in a baraita that Rabbi Yosei said: There was an incident involving Rabbi Akiva, who came to the synagogue, and his etrog was so large that he carried it on his shoulder. Apparently, one can fulfill his obligation with a large etrog. Rabbi Yehuda said to him: Is there proof from there? In that case, too, the Sages said to him: That is not beauty.

MISHNA: One may bind the lulav only with its own species; i.e., one of the four species taken with the lulav. This is the statement of Rabbi Yehuda. Rabbi Meir says: One may do so even with a string or with a cord. Rabbi Meir said: There was an incident involving the men of Jerusalem who would bind their lulavim with gold rings. The Sages said to him: They would bind it with its own species beneath the rings, which serve a merely decorative purpose and not a halakhic one.

GEMARA: Rava said: One may bind the lulav even with fibers that grow around the trunk of the date palm, and even with a piece of the trunk of the date palm. And Rava said: What is the rationale for the opinion of Rabbi Yehuda? He holds that a lulav requires binding, and if one brings another species to bind the lulav, there will be five species and he will violate the prohibition against adding to the mitzvot.

And Rava further said: From where do I say this halakha that fibers and the trunk of the date palm are the species of the lulav? It is as it is taught in a baraita that it is written: “You shall reside in sukkot for seven days” (Leviticus 23:42), which means a sukka of any material, as the Torah was not particular about the material to be used for the roofing; any species may be used as long as it grew from the ground and it is not susceptible to impurity. This is the statement of Rabbi Meir. Rabbi Yehuda says: The mitzva of sukka is practiced only with the four species of the lulav as roofing. And, he claims, logic dictates that it is so, as it is derived by means of an a fortiori inference: Just as the mitzva of lulav, which is not practiced at night as it is during the day, is practiced only with the four species, with regard to the mitzva of sukka, which is practiced at night as it is during the day, is it not right that its roofing should be only from the four species?

The Rabbis said to him: That is not an a fortiori inference, as any a fortiori inference that you infer initially to be stringent, but ultimately it is to be lenient, is not a legitimate a fortiori inference. If ultimately the stringency leads to a leniency, the entire basis of the inference is undermined.