ANSWERS TO REVIEW QUESTIONS
prepared by Rabbi Eliezer Chrysler
Kollel Iyun Hadaf, Jerusalem
Previous daf Bava Basra 18
BAVA BASRA 18 (25 Nisan) - dedicated by Sandy and Les Wiesel in memory of
Les's father, Menachem Yehuda ben Avigdor Yosef Wiesel, who perished in the
(a) If, as Rava explains, our Mishnah is speaking even when the neighbor has
not yet built a wall, then, when the Tana rules ...
1. ... 'Marchikin es ha'Geffes ve'es ha'Zevel ... mi'Koslo shel Chavero
Sheloshah Tefachim ... ', he is coming to teach us - that all the things
listed there cause damage to a wall.
(b) The Mishnah later forbids Reuven to open a bakery, a dyeing-shop or a
stable underneath Shimon's storehouse, implying that he would be permitted
to do so, if the storehouse was not yet there. Rava will attribute this to
the fact - that whatever has to do with residence (including one's animals)
is permitted as long as there is no-one who currently suffers from one's
2. ... 'Marchikim es ha'Zera'im ve'es ha'Machrishah ... min ha'Kosel
Sheloshah Tefachim ... ', he is coming to teach us - that the wetness caused
by these things (though it is not clear how this applies to plowing) causes
damage to a wall.
3. ... 've'es ha'Rechayim Sheloshah ... ', 've'es ha'Tanur Sheloshah ... '-
he is coming to teach us - that vibration and heat cause damage to a wall,
(c) The Mishnah adds - that if the stable was there first, it is permitted
(a clause that the Tana did not insert in any of the previous cases),
bearing out what we just said.
(a) The Mishnah later forbids Reuven to plant a tree within four Amos of
Shimon's field, to which the Beraisa adds - 'because of Avodas ha'Kerem'
(the four Amos that are required to work with one's oxen and cart, plowing
the vineyard and picking the fruit (and the same applies to an orchard).
(b) The reason that it is not forbidden anyway, according to Rava, is -
because the Tana speaks in a case when there is a strip of rocky terrain
dividing between the two fields, which prevents the roots from spreading
across from Reuven's field to Shimon's.
(c) The Mishnah later permits Reuven and Shimon to plant trees right up to
the wall that divides their fields dispensing with the Isur of Kil'ayim. We
are not concerned about the roots of Reuven's tree growing under the wall
into Shimon's field - because there too, the Tana speaks when there is a
strip of rocky terrain ... .
(d) When the Tana rules in the Seifa 'Hayu Sharashav Yotz'in be'Toch shel
Chavero, Ma'amik Sheloshah Tefachim' - he is referring to a case where there
is no strip of rocky terrain. That is where it is necessary to plant the
roots three Tefachim deep.
(a) The Mishnah later teaches 'Marchikin es ha'Ilan min ha'Bor
Esrim-ve'Chamesh Amah. If, as Rava explains, the Tana is speaking even when
there is no pit as yet in the second field, his Chidush will be - that a
tree's roots damage a pit as far as twenty-five Amos.
(b) Even though planting the tree is normally prohibited even before the pit
exists, the Tana writes in the Seifa 've'Im Ilan Kadam, Lo Yikotz' - because
he is speaking when Reuven planted the tree before selling the piece of land
next to it to Shimon, who now wants to dig a pit (like Rav Papa will explain
shortly, with regard to a similar problem).
(a) The Tana Kama there states 'Marchikin es ha'Mishrah min ha'Yerek ... ',
implying that if there would be no vegetables, Reuven would be permitted to
place his soaking-house next to Shimon's field. According to Rava - the same
will apply even if there are no vegetables there, and the reason that the
Tana mentions the vegetables is to teach us that a soaking-house is harmful
(b) The Tana Kama forbids Reuven to plant mustard-seeds in the vicinity of
Shimon's bees - because they first eat the flowers of his mustard-seeds, and
then, to neutralize the sharp taste, they consume their own honey (causing a
loss to Shimon).
(c) Rebbi Yossi permits it - because, he says, since the bees eat his
mustard-seed flowers, Shimon is no less of a Mazik than he is, so let him
move his aviary.
(d) Despite the fact that according to Rava, the Mishnah is speaking even
before Shimon opened his aviary there (because it is forbidden to place a
potential Mazik close to the Nizak's Reshus in anticipation of the Nizak
pacing his article there) - Rav Papa establishes the Machlokes between Rebbi
Yossi and the Tana Kama when, at the time that Reuven planted his
mustard-seeds, the entire field belonged to him, and he subsequently sold
Shimon part of it. And it is in that section, close to Reuven's
mustard-seeds, that Shimon now decides to place his aviary.
(a) Despite the fact that Rav Papa just established the Machlokes between
Rebbi Yossi and the Rabbanan (with regard to the mustard-seeds and the bees)
when Reuven sold Shimon half the field only after he had planted his
mustard-seeds, the Rabbanan nevertheless obligate Reuven to move them -
because they hold 'al ha'Mazik Le'harchik es Atzmo min ha'Nizak' (even if
the Mazik was there first).
(b) The problem with attributing Rebbi Yossi's ruling to the S'vara 'al
ha'Nizak Le'harchik es Atzmo min ha'Mazik' is - that, in that case, why does
he not argue in the other cases in the Mishnah too. (Why, for example, does
he concede to the Rabbanan that Reuven must move his soaking house away from
(c) So we assume that Rebbi Yossi too, holds 'al ha'Mazik Le'harchik es
Atzmo min ha'Nizak', and the reason that Rebbi Yossi argues in the case of
the mustard-seeds and the bees (even though he concedes to them by the
soaking-house and the vegetables) is - because the bees damage the seeds no
less than the seeds damage the bees (as we explained above), which is not so
in the other cases in the Mishnah.
(d) The Rabbanan counter Rebbi Yossi's argument. The bees, they argue - do
not damage the mustard-plant at all ...
1. ... not the seeds - which they cannot get to, and ...
2. ... not the leaves - which grow again.
(a) Rebbi Yossi rules that, in a case where Reuven plants a tree within
twenty-five Amos of Shimon's pit - he is not obligated to move it away,
because he holds ...
(b) ... 'al ha'Nizak Le'harchik es Atzmo min ha'Mazik.
(c) We reconcile Rebbi Yossi regarding the mustard-seeds and the bees with
this latter ruling of his - by establishing that Rebbi Yossi is actually
debating with the Rabbanan according to their own reasoning ('al ha'Mazik
Le'harchik ... ' [even though he personally holds 'al ha'Nizak Le'harchik
... ']). And he merely means to ask them whether they will not agree with
him that, at least in the case of the seeds and the bees, Reuven ought to be
Patur, for the reason that we cited. But the Rabbanan refute his argument,
on the grounds that the bees do not damage the mustard-seeds (as we