Rashi tells us that in many places the word "aliyah" is used to mean "enter" in Gemara Sukkah, since generally speaking the sukkah was made on the roof. Does Rashi mention this in the entire Gemara Sukkah anywhere? If not, it sure seems odd something that is important for Gemara Sukkah he doesn't explain in that Gemara, but explains at length in Gemara Shabbos.
Menachem Weiman, St. Louis, United States
Rashi is coming to exclude the possibility of explaining the mishna with a tree-house which has two big boards and a shorter board supported by a tree. This explanation is brought by the Ritva in Sukka 21 and Meiri. However Rashi in Sukka 22b S.V. Shtayim seems to accept this explanation which is logical for the word Olin. We must therefore assume that these are two alternative explanations of the Mishna, as Rashi on the Shas had different versions and alternative explanations in different places.
A possible reason for Rashi's change of explanation is Tosfos's question brought by Ritva Shabbos- why should a person not enter a sukka which has a tree on its side? This is not "using" the tree even if the sechach is supported by the tree, as a person may sit under a tree on Shabbos! For this reason Rashi in Sukka preferred the other explanation. (where the tree is literally supporting one's feet on one side)
Yoel Domb