ANSWERS TO REVIEW QUESTIONS
prepared by Rabbi Eliezer Chrysler of Kollel Iyun Hadaf, Yerushalayim
Rosh Kollel: Rabbi Mordecai Kornfeld
(a) Rav Dimi quotes Rebbi Yochanan as saying - that both people in the Reshus ha'Rabim and in the Reshus ha'Yachid are permitted to put down heavy objects on to an area in between the two Reshuyos that is less than four by four Tefachim (provided they do not exploit the situation by putting them down from one Reshus and then taking them into the other - though this prohibition will not apply in our case, as we explained above).
(b) Rav agrees with Rebbi Yochanan - by Reshuyos d'Oraysa, and the reason that he is strict here in our Sugya (with regard to the top of the wall) is because we are dealing with Reshuyos de'Rabbanan (since they are both Reshuyos ha'Yachid), and Rav holds that Chazal needed to safeguard their own laws more so than they did Torah-laws.
(a) When Rav Nachman says that if a wall is ten Tefachim high from one Chatzer, but less from the upper-level Chatzer that adjoins it, one gives it to the latter Chatzer - he means to say that it is the Chatzer that has easier access to the wall whose residents are permitted to use it, and not those other Chatzer.
(b) Had Rav Nachman taught his Din only by a wall - we would have restricted it to a wall, since a low wall really is easy to use; whereas a shallow ditch, which may well be easier to use than a deep one, but not easy. Consequently, we would not have applied his Din to a ditch. And had he taught his Din by a ditch, we would have confined it to a ditch, where one has no reason to be afraid; whereas by a wall, where there is reason to be afraid that the objects which he places there may fall off (a fear which is equally applicable to a low wall as to a high one), perhaps we will not give it to either Chatzer.
(a) If one reduces the height of the wall by fixing an object that is less than four Tefachim long to the foot of the wall - the Gemara initially maintained that one is permitted to one use the section of wall, that is above that point. It concludes however, that since it does not permit using the entire wall (because it is not considered a Pesach), it is Batel to the wall and one may not even use the wall above that point either.
(b) But if he removes a section less than four Tefachim long, from the top of the wall - that section is not considered a Reshus but a Makom Petur, and he is permitted to use it.
(a) A large overturned dish (which is four by four Tefachim) placed at the foot of the wall, will be effective as a Pesach only if it is properly fixed to the ground (to the extent that it requires tools to remove it).
(b) The fact that it has a lip (that now contains earth which will inevitably be moved together with the dish when it is pulled out of the ground) will not suffice, to render it fixed to the ground - due to the fact that, since this does not forbid removing the dish on Shabbos (because Tiltul min ha'Tzad may be moved on Shabbos under such circumstances) it is not called properly fixed.
(a) A ladder from Tzuri - has four rungs, an Egyptian ladder, less. It is due to its lightness that the latter stands to be carried away on Shabbos, and is not therefore permanent enough to be considered a Pesach.
(b) A ladder must be at least four Tefachim wide to qualify as a Pesach.
(c) Two ladders, one on either side of a wall dividing two courtyards ...
1. ... must be less than three Tefachim apart, for them to serve as a Pesach - if the wall is less than four Tefachim wide.
2. ... can be any distance apart, when its width is at least four Tefachim, because then, he is able to walk along the wall from one ladder to the other.
(a) If two wooden platforms are built next to the wall, one on the ground and the other on stilts above the first - this constitutes a Pesach if the lower platform is four Tefachim wide (irrespective of the dimensions of the top one), or if the top one is four Tefachim and there is less than three Tefachim between them.
(b) The same two conditions will apply here as in the previous case: either the bottom rung is four Tefachim wide or the upper one is, and there is less than three Tefachim between them.