(Beraisa - Rebbi): If a Sukah measures four Amos even if it does not have four walls, it is valid.

R. Shimon: If it has four walls, even though it does not measure four Amos, it is valid.

R. Yehuda: Even if it does not measure four Amos nor have four walls, it is valid. (Note: This entry follows the text of the Korban HaEidah.)

Similarly, R. Yehuda obligates a room in Mezuzah, even if the room does not measure four Amos nor have four walls.

It is logical to say that R. Yehuda agrees to the Rabbanan (R. Shimon and Rebbi who say that if a Sukah measures four Amos or has four walls it is valid - as R. Yehuda says that it is valid even without either condition); but the Rabbanan do not agree to R. Yehuda that even if the room measures four Amos and has four walls, it is exempt from Mezuzah as it is certainly termed a temporary dwelling.

R. Shimon said that a Sukah must have four walls; Rabbanan said that it must have three.

Source for Rabbanan: (Vayikra 23, 42&43) "Sukos''- "Sukos'' - "Sukos'' - the Torah uses the word three times, one for the Schach and two for the walls; the third wall is Rabbinically required.

Source for R. Shimon: (Ibid) "Sukas'' - "Sukas'' - "Sukos'' - the first two times the word is written without the letter Vav, implying they are singular and the third time it is written with a Vav, implying plural, meaning two. Therefore, the total number is four - one for the Schach and three for the walls; the fourth wall is Rabbinically required.

Version #2 of sources (R. Chiya bar Ada): There were two Amoraim - one gave the source for Rabbanan and one for R. Shimon -

Rabbanan: The Pasuk states (Yishayahu 4, 6), "A Sukah will be a shade in the daytime from the hot sun'' - this Pasuk teaches that the Sukah must provide shade, meaning that there must be Schach. The word "Sukah'' is used three times in the Pasuk (in Sefer Vayikra) to require three walls.

R. Shimon: (Ibid), "A Sukah will be shade etc.'' this teaches the Schach. In the Pasuk in Sefer Vayikra the Pasuk says "Sukas'' - "Sukas'' - "Sukos'' - this totals four, meaning that a Sukah must have four walls.

Version #3 of sources (Rabbanan of Kisarin): The earlier Pasuk is expounded as follows - "A Sukah will be as a shade in the daytime from the hot sun'' = one; "as a protection and shelter'' = two. "From storm and rain'' - Rabbanan count this phrase as one and R. Shimon counts it as two.

Support for (h) earlier (Beraisa): Two must be full walls and the third may even be one Tefach long (as the third wall is only Rabbinic).

R. Chiya quoting R. Yochanan: If two walls are four Tefachim long and the third is even a Tefach, it is valid.

Query (R. Hoshiya): If the third wall of a Tefach was positioned in the middle, is it valid?

Query #2: If the four-Tefach walls were positioned in the middle, is it valid?

R. Yaakov bar Acha: A case like this (where the walls were distant) came before R. Yasa and he ruled that it was valid.

Support (Beraisa): If a courtyard is surrounded by pillars, they serve as walls.

Question (Beraisa): If they are built correctly, they are valid; if not, they are invalid.

They thought that incorrectly means that they are positioned in the middle. (This would mean that this Beraisa contradicts the earlier Beraisa (p).)

Resolution (R. Shmuel bar Rav Yitschak): No, it means that they were not positioned opposite each other.