Sukkah, Daf Yod Tet, Part 1
Introduction
Today’s daf continues to deal with the issue of whether we consider the edge of a roof to fictionally descend to the ground so that it forms a wall, which could validate the sukkah.
תנן: וכן חצר המוקפת אכסדרה. ואמאי? נימא פי תקרה יורד וסותם!
We have learned: similarly in the case of a courtyard which is surrounded with an exedra. But why? Should it not rather be assumed that the edge of the roof descends and fills in [the space]?
The Mishnah on 17a allowed one to build a sukkah in the middle of a courtyard which is surrounded by an "exedra," a portico covered by a roof, but only as long as the walls of the house are not four cubits removed from the skhakh. But if we invoke the principle of assuming that the edge of the roof descends to the ground, we could consider the edge of roof of the exedra, upon which the skhakh rests, to go to the ground and act as a wall. Then this sukkah would be valid even if the skhakh was more than four cubits from the real walls. The mishnah is therefore a difficulty on Abaye who holds that we can consider the edge of the roof of the exedra to extend to the ground.
תרגמה רבא אליבא דאביי: כשהשוה את קירויו.
Rava explained according to Abaye that this is a case where one made the beams level.
Rava answers the difficult on Abaye by saying that the mishnah is a case where the beams used for skhakh were placed on a level equal to the roof of the exedra. Thus the roof of the exedra cannot be seen in the sukkah and in such a case there would be no way to bring the roof down to the ground to fictitiously create a wall.
בסורא מתני להא שמעתא בהאי לישנא. בפומבדיתא מתני: סיכך על גבי אכסדרה שאין לה פצימין – דברי הכל פסולה. יש לה פצימין, אביי אמר: כשרה, רבא אמר: פסולה. אביי אמר: כשרה, אמרינן לבוד. רבא אמר: פסולה, לא אמרינן לבוד. והלכתא כלישנא קמא.
In Sura they taught these statements in the above form.
In Pumbedita they taught [it as follows]: If a man placed skhakh over an exedra which has no pillars, it is invalid according to all.
If it has pillars: Abaye declares it valid, while Rava declares it invalid.
Abaye declares it valid, since we apply the law of lavud.
Rava declares it invalid, since we do not apply the law of lavud.
And the law is according to the former version.
The above tradition of the debate between Abaye and Rava was the Suran version of the debate. This version (part 5 of the previous daf) read: "If one placed skhakh over an exedra which has pillars, it is valid; If it has no pillars: Abaye declares it valid and Rava declares it invalid." Thus everyone agrees that if the exedra has pillars it is valid and they dispute a case where it doesn’t have pillars.
In Pumbedita they teach a more stringent version of the dispute. In this case, if there are no pillars everyone agrees that it is invalid. This implies that no one says that we can fictitiously extend the roof of the exedra to the ground. They disagree if they have pillars, each of which is less than three handbreadths from the next. Abaye says we invoke the rule of "lavud" less than a three handbreadth gap is considered as if it doesn’t even exist. Rava says we do not apply this rule.
Finally, the sugya ends saying that we follow the first version of the dispute. Post-talmudic halakhic authorities also rule according to Rava. Therefore if there are pillars, the sukkah is valid because of the principle "lavud." But if there are no pillars, the sukkah is invalid because we don’t invoke the principle of drawing down the roof to create a wall.
רב אשי אשכחיה לרב כהנא דקא מסכך על גבי אכסדרה שאין לה פצימין. אמר ליה: לא סבר מר הא דאמר רבא: יש לה פצימין – כשרה, אין לה פצימין – פסולה? אחוי ליה נראה מבפנים ושוה מבחוץ. אי נמי: נראה מבחוץ ושוה מבפנים. דאתמר: נראה מבחוץ ושוה מבפנים – נידון משום לחי, ולחי היינו פצימין.
R. Ashi found R. Kahana placing skhakh over an exedra which had no pillars. He said to him: Does not the master hold the opinion which Rava stated, that if it has pillars it is valid, but if it has no pillars it is invalid?
He showed him [that a pillars] was visible within though level on the outside, or visible from without, though level from within, for it has been stated, If it is visible from without and level from within, it is regarded as a valid side-post , and a side-post is in this respect like pillars.
This story ends the discussion concerning the sukkah built in the exedra (it is common for such stories to come at the end of long halakhic discussions). Rav Ashi finds his teacher, Rav Kahana building his sukkah in an exedra that has no pillars. He asks him how he can do such a thing. After all, the accepted halakhah is according to Rava who holds that without pillars, such a sukkah is invalid. Rav Kahana responds by showing him that there actually was one pillar there that could count as the third wall (evidently two walls were real, and a sukkah’s third wall can be as small as one handbreadth.) This sukkah is valid whether this pillar could be seen from within the sukkah, meaning it is within the other two walls, or even if it is outside the sukkah. Such a pillar, even if it can’t be seen within the sukkah, counts as a third wall!
The proof text for this concerns the side-post, the structure needed to create an eruv in the courtyard. This is a post placed next to the gate exiting the courtyard. The side-post need not be visible from within the courtyard to count as a side-post. R. Kahana claims that the same is true for the pillar to count as a third wall in the sukkah. It need not be seen inside the sukkah.