The mishna summarizes that this is the principle: Any case where, were the tree removed, the sukka would be able to remain standing in and of itself, it is fit, and one may ascend and enter it on the Festival, since the tree is not its primary support.

GEMARA: The Gemara comments: In accordance with whose opinion is the mishna? It is in accordance with the opinion of Rabbi Akiva, as it is taught in a baraita: In the case of one who establishes his sukka at the top of the ship, Rabban Gamliel deems it unfit and Rabbi Akiva deems it fit.

There was an incident involving Rabban Gamliel and Rabbi Akiva, who were coming on a ship. Rabbi Akiva arose and established a sukka at the top of the ship. The next day the wind blew and uprooted it. Rabban Gamliel said to him: Akiva, where is your sukka? It was unfit from the start.

Abaye said: Everyone agrees that in a case where the sukka is unable to withstand a typical land wind, the sukka is of no consequence and it is not even a temporary residence. If it is able to withstand even an atypical land wind, everyone agrees that the sukka is fit. Where they disagree is in a case where the sukka is able to withstand a typical land wind but is unable to withstand an atypical land wind, which is the equivalent of a typical sea wind. Rabban Gamliel holds: In order to fulfill the mitzva of sukka, we require a permanent residence, and since it is not able to withstand an atypical land wind, which is like a typical sea wind, it is of no consequence and is not a sukka at all. Rabbi Akiva holds: In order to fulfill the mitzva of sukka, we require a temporary residence, and since it is able to withstand a typical land wind, it is fit, although it is unable to withstand a typical sea wind.

§ The mishna continues: Or if one establishes his sukka atop a camel, the sukka is fit. The Gemara asks: Who is the tanna of the mishna? It is in accordance with the opinion of Rabbi Meir, as it is taught in a baraita: In the case of one who establishes his sukka atop an animal, Rabbi Meir deems it fit and Rabbi Yehuda deems it unfit. The Gemara asks: What is the rationale for the opinion of Rabbi Yehuda? The Gemara answers that it is as the verse states: “You shall prepare for yourself the festival of Sukkot for seven days” (Deuteronomy 16:13), from which Rabbi Yehuda derives: A sukka that is suitable for seven days is called a sukka, while a sukka that is not suitable for seven days is not called a sukka. It is prohibited to climb upon an animal on the first day of the festival of Sukkot, and therefore a sukka atop an animal is unfit, as it cannot be used all seven days.

And Rabbi Meir, who holds that the sukka is fit, would say: By Torah law, this sukka is also suitable for use on a Festival and on Shabbat, as there is no Torah prohibition against using an animal on those days, and it is the Sages who issued a decree prohibiting it. The fact that it is prohibited by rabbinic decree does not render the sukka unfit.

However, if one utilized his animal as a wall for a sukka and did not establish the entire sukka atop the animal, Rabbi Meir deems it unfit and Rabbi Yehuda deems it fit, as Rabbi Meir would say: With regard to any animate object, one may neither establish it as a wall for the sukka, nor as a side post placed at the entrance to an alleyway to render it permitted to carry in the alleyway on Shabbat, nor as one of the upright boards placed around wells to render the area a private domain and permit one to draw water from the well on Shabbat, nor as the covering for a grave. In the name of Rabbi Yosei HaGelili the Sages said: Nor may one write bills of divorce on it.

The Gemara asks: What is the rationale for the opinion of Rabbi Meir, who rules that an animal is unfit for use as a partition in areas of halakha where a partition is required? Abaye said: It is due to the concern lest the animal die, leaving the sukka without a wall. Rabbi Zeira said: It is due to the concern lest it flee. The Gemara explains the practical halakhic differences between the two opinions. In the case where one established a wall with a tied elephant, everyone agrees that the sukka is fit, as even if it dies and falls, its carcass still has a height of ten handbreadths and is fit for the wall of a sukka. Where they disagree is in the case of an elephant that is not tied. According to the one who said: It is due to the concern lest the animal die, we are not concerned in this case, as the carcass would remain a fit wall. According to the one who said: It is due to a decree lest it flee, we remain concerned.

The Gemara asks: According to the one who said: It is due to a decree lest it die, let us also be concerned lest it flee, as that too is a reasonable concern. Rather, this is the explanation: In the case where one established a wall with an elephant that is not tied, everyone agrees that the sukka is unfit lest it flee. Where they disagree is in the case of a tied animal. According to the one who said: It is due to a decree lest the animal die, we are concerned, as although it cannot flee, it might die, and the carcass of a typical animal is not ten handbreadths high. And according to the one who said: It is due to a decree lest it flee, we are not concerned.

The Gemara asks: And according to the one who said: It is due to a decree lest it flee, let us also be concerned lest it die. The Gemara answers: That is not a concern because death is not common. The Sages do not issue decrees with regard to uncommon circumstances. The Gemara asks: But according to all opinions, isn’t there the space between its legs, which is like a breach in a wall? How can one establish a partition whose breached segment exceeds its standing segment? The Gemara answers: He establishes a partition for it by filling the gaps with hard palm leaves and laurel leaves, sealing the breach.

The Gemara asks further: And even though there is no concern lest the animal die, perhaps it will crouch, leaving a wall that is less than ten handbreadths? The Gemara answers: It is referring to a case where the animal is tied with ropes from above so that it cannot crouch. Based on that explanation, the Gemara asks: And according to the one who said: It is due to a decree lest it die, there is also no concern since it is tied with ropes from above. Even if the animal died, it would remain in place as a fit partition. The Gemara answers: Sometimes the ten-handbreadth wall consists of the animal that is a bit higher than seven handbreadths established adjacent to the roofing, less than three handbreadths away.