THOUGHTS ON THE DAILY DAF
brought to you by Kollel Iyun Hadaf of Har Nof
Rosh Kollel: Rav Mordecai Kornfeld
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1) THE TWO POINTS OF DISPUTE BETWEEN REBBI YOSI AND REBBI MEIR
QUESTION: Rava explains that Rebbi Yosi and Rebbi Meir argue about two
points. First, they argue about the Halachah in a case in which an Ohel
the size of a Tefach transfers Tum'ah to the threshold; one maintains that
the entire threshold is considered to be "inside" the house (and Tum'ah
spreads to the house), and the other maintains that only part of the
threshold is considered to be inside the house -- the part that is inside
the house when the door is closed. Second, they argue about what comprises
a "Chalal Tefach" -- a hollow passageway such as the throat, or even a
solid passageway, such as the entire width of the neck.
2) WHY WOULD "TUMAH" WHICH IS ON THE THRESHOLD NOT BE "METAMEI" THE HOUSE?
Why does Rava say that Rebbi Yosi and Rebbi Meir argue about both
Halachos? They clearly argue with regard to the threshold, since Rebbi
Yosi explicitly mentions the place where the door closes. However, there
is no indication that they also argue about whether the solid part of the
neck is included in the Tefach!
ANSWER: TOSFOS (DH Amar) explains that Rebbi Yosi uses the term "Ro'im"
("we look"). This implies that there is something that requires
examination and is not clearly visible, such as Tum'ah inside of a dog, or
the size of the passageway of the dog's throat. If Rebbi Meir and Rebbi
Yosi argue only in the case of a Tefach-thick neck that transfers Tum'ah
to a threshold, the only thing we need to know is the extent to which the
neck of the dog stretches (at the point where the door closes). However,
since this can be easily determined, the term "Ro'im" is not appropriate.
From the word "Ro'im" we may infer that Rebbi Yosi argues with Rebbi Meir
on a point that involves a closer examination.
QUESTION: Rebbi Yosi maintains that Tum'ah that is on the threshold of a
house can be Metamei the house only when it is within the point at which
the door closes.
3) THE TANA WHO ARGUES WITH REBBI YOSI
Why, though, should the house not be Tamei even when the Tum'ah is outside
of the point at which the door closes? When the door is open, the Tum'ah
is under the lintel; the lintel is an Ohel and should transfer the Tum'ah
to the house!
ANSWER: TOSFOS (DH Anan) answers that Rebbi Yosi is discussing a situation
in which the part of the threshold that remains outside after the door is
closed is less then a Tefach wide. Since the closed door separates that
part of the lintel from the rest of the house, the lintel does not
constitute an Ohel, because it is less than a Tefach wide, and thus it
cannot transfer Tum'ah.
QUESTION: Rebbi Yosi maintains that Tum'as Ohel can also be Metamei
through Maga. The Gemara here asks who is the Tana who argues with Rebbi
Yosi and maintains that Tum'as Ohel and Tum'as Maga do not combine to be
RASHI (DH Man Tana) explains that the Gemara is asking who is the Tana of
the Mishnah in Ohalos (3:1) quoted earlier (125a-b) who says that Tum'as
Ohel does not combine with Tum'as Maga to be Metamei.
Why does Rashi assume that Rebbi Yosi must be arguing with the Tana of
that Mishnah? The Mishnah there is discussing the specific case of one who
touches a half-k'Zayis of Tum'ah while he is standing under one roof
together with another half-k'Zayis of Tum'ah. Perhaps Rebbi Yosi agrees
that in that case the Tum'as Ohel does not combine with the Tum'as Maga
(and the person remains Tahor), because, as Abaye (125b) says, in that
case the Ohel is more than a Tefach above the Tum'ah (and such Tum'as Ohel
is not considered Maga), or because, as Rava (125b) says, an Ohel which
effectively draws Tum'ah from one place to another with one ceiling is not
the same form of Tum'ah as Maga! (TOSFOS DH Man)
(a) TOSFOS argues with Rashi's explanation. He explains that the Gemara
does not assume that the Tana of the Mishnah in Ohalos is arguing with
Rebbi Yosi. Rather, the Gemara is inferring that there is a Tana who
argues with Rebbi Yosi from the fact that the Gemara earlier (125b) says,
"Rebbi Yosi holds that Ohel is a form of Maga." This implies that there
are others who do *not* consider it a form of Maga. The Gemara is asking
who those other Tana'im are.
(b) Perhaps Rashi understands the question of the Gemara as follows. The
Gemara infers from the Mishnah in Ohalos that even when the Ohel is *less*
than a Tefach high (according to Abaye), or the Tum'ah is *not* drawn from
place to place by the Ohel (according to Rava), it would still not be
Metamei with Tum'as Maga. This is because the first part of that Mishnah
(according to Rebbi Zeira) says that only an Ohel that is sheltering an
object of Tum'ah that is between two chests ("Tum'ah Retzutzah") is like
Maga, implying that all other cases of Ohel are not like Maga. (Tosfos
himself notes this inference earlier; see Tosfos to 125b, DH Amar.) (M.
4) A BONE THE SIZE OF A BARLEY GRAIN
QUESTION: The Gemara quotes the Beraisa in which Rebbi Shimon says that
there are three types of Tum'ah of Mes that are Metamei in two ways out of
the three ways that Tum'ah can be transferred -- Ohel, Maga, and Masa. One
of these types of Tum'ah is the Tum'ah of an "Etzem k'Se'orah," a human
bone the size of a barley grain, which is Metamei through Maga and Masa,
but not through Ohel. What is the source that an Etzem k'Se'orah is not
Metamei through Ohel?
5) THE HALF-MOUSE
ANSWER: RASHI (DH Etzem k'Se'orah) explains that this law is a Halachah
TOSFOS (DH Etzem k'Se'orah) argues with Rashi's explanation, because the
Gemara in Nazir (53b) explicitly derives the Tum'ah of an Etzem k'Se'orah
from verses in the Torah. Tosfos, however, does not offer an alternative
source for the law that an Etzem k'Se'orah is not Metamei through Ohel.
The TIFERES YAKOV has difficulty with the statement of Tosfos. The verses
cited by the Gemara in Nazir there do not actually teach that a bone the
size of a barley grain is Metamei! The Gemara in Nazir does derive some
laws regarding the Tum'ah of bones from verses. It quotes the verse,
"v'Chol Asher Yiga Al Penei ha'Sadeh... O v'Etzem Adam" -- "And whoever
touches one who was slain with a sword in the open fields, or a dead body,
or a bone of a man... shall be Tamei for seven days" (Bamidbar 19:16),
from which the Gemara learns that a measurement of one-quarter of a Kav
(Rova ha'Kav) of bones is necessary to be Metamei through Ohel (as opposed
to the smaller measurement of a grain of barley). Similarly, the Gemara
(Nazir 54a) derives from the verse, "v'Al ha'Noge'a ba'Etzem" -- "... and
upon the one who touched a bone" (Bamidbar 19:18), that a bone is Metamei
through *Maga* when it is the size of a barley grain. However, it is clear
that there is no mention or hint in the verses to the Shi'ur of a quarter
of a Kav or the Shi'ur of a barley grain! It must be that the Gemara
simply is applying Halachos l'Moshe mi'Sinai (that teach us these
Shi'urim) and inserting them into the context of the verses! How, then,
can Tosfos say that these amounts and Halachos are derived from the verses
and are not learned from a Halachah l'Moshe mi'Sinai? In fact, we find
that Tosfos in Nazir (53b, DH O v'Etzem Adam) explicitly agrees with the
words of Rashi here and says that these amounts are Halachos l'Moshe
mi'Sinai, while the verse is merely an Asmachta!
The LEV ARYEH initially agrees with Tosfos' question on Rashi, and he adds
that Tosfos' source is a statement of Rebbi Yochanan in Nazir (54a). The
Gemara there quotes a Beraisa that says that the verse, "O va'Mes" -- "or
[touched] a dead person" (Bamidbar ibid.) teaches that a limb of a dead
person is Metamei. The verse there is discussing Tum'as Maga. Rebbi
Yochanan understands that the verse is discussing a case in which the limb
has a piece of bone in it the size of a barley grain. According to Rebbi
Yochanan, we do not need that verse to teach that the limb is Metamei
through Maga, because we already know that a bone the size of a barley is
Metamei through Maga. Rebbi Yochanan therefore says that the verse is
teaching (through the principle of "Im Eino Inyan") that a bone the size
of a barley grain is Metamei through *Masa*. Since we rule like Rebbi
Yochanan, we have a source in the verse that a bone the size of a barley
grain is Metamei through Maga and Masa, while the earlier Derashah in the
Gemara there teaches that only a bone the size of a Rova ha'Kav is Metamei
However, the Lev Aryeh points out that there is another Gemara that
strongly implies that there is no source in the verse that an Etzem
k'Se'orah is not Metamei through Ohel. The Gemara states in a number of
places (see, for example, Sukah 5b-6a) that we derive from the verse,
"Eretz Chitah u'Se'orah..." (Devarim 8:8, which lists the seven species of
fruits of Eretz Yisrael), many of the Shi'urim in Halachah. From the word
"barley" in the verse we derive that a bone the size of a barley grain is
Metamei through Maga and Masa, but not through Ohel. The Gemara asks that
it says nowhere in the verse that these amounts are specifically for these
topics to which the Gemara ascribes them. The Gemara concludes that the
verse is merely an Asmachta, and we know the Shi'urim from a Halachah
l'Moshe mi'Sinai. This clearly seems to support the words of Rashi here.
Therefore, the Lev Aryeh concludes that Rashi's explanation is correct.
OPINIONS: The Mishnah here mentions a mouse "which is half-flesh and
half-earth; one who touches the flesh part is Tamei, and one who touches
the earth part is Tahor."
6) "GOLEL" AND "DOFEK"
We find this creature mentioned elsewhere in the Gemara in a different
context. The Gemara in Sanhedrin (91a; see Insights there) relates that a
certain heretic challenged Rebbi Ami regarding Techiyas ha'Mesim, saying
that it is not possible for a decomposed body, which turns into earth, to
rise again as a living body. One of Rebbi Ami's proofs for Techiyas
ha'Mesim was the fact that there is a rodent that lives in the valley
"that today is half-flesh and half-earth, and tomorrow it becomes
According to modern scientific knowledge of the biological world, all
living things come about through propagation and regeneration. However, in
the times of the Chachamim, it was accepted by all that many creatures are
formed from inanimate objects. The Gemara in Shabbos (107b) permits
killing on Shabbos a louse that is produced from sweat spontaneously (see
TOSFOS to Shabbos 12a). The SHULCHAN ARUCH (YD 84:15) prohibits eating
birds that grow on trees because of the Isur of Sheretz. It was also
commonly believed that flies are produced from rotting meat. (It was only
towards the end of the seventeenth century (CE) that experiments by
Francesco Redi and Louis Pasteur surprised the world by proving that
substances that were protected from the air did not produce insects.) The
reason Rebbi Ami proves his point from the rodent is because the rodent
arises not from a living organism, but from dirt, like the dead who will
come to life.
Is there any evidence today to support the existence of rodents that are
formed from the earth? (The following discussion is culled primarily from
the research of Rabbi Nosson Slifkin (www.zootorah.com), published in his
book, "Mysterious Creatures," Targum Press, Jerusalem, 2003.)
(a) The RAMBAM seems to confirm the existence of such a creature. In
Perush ha'Mishnayos here he writes, "This is a well-known matter; there is
no end to the number of people who have told me that they have seen it.
Such a thing is indeed astonishing, and I have no explanation for it."
The TIFERES YISRAEL (Bo'az, Chulin 9:6) also defends the existence of such
a creature. He writes, "I have heard heretics mocking with regard to the
creature that is discussed here and in Sanhedrin 91a, and denying it,
saying that there is no such thing at all. Therefore, I have seen fit to
mention here that which I found written in a Western European work
compiled by a scholar renowned among the scholars of the world. His name
is Link, and the book is titled 'Auervelt.' In volume I, page 327, he
writes that such a creature was found in Egypt in the district of Thebes,
and in the Egyptian language that rodent is called 'dipus jaculus'; and in
German it is called 'springmaus.' Its forequarters -- head, chest, and
hands -- are perfectly formed, but its hindquarters are still embedded in
the earth, until after several days when it fully changes to flesh. And I
say, 'How great are Your works, Hashem!'"
(b) However, Professor S. Z. Leiman has raised doubts about the accuracy
of the Tiferes Yisrael's understanding of Link's words (in his article
entitled, "Rav Yisrael Lipshutz and the Mouse that is Half Flesh and Half
Earth," printed in Chazon Nachum, New York, Yeshiva University 1998). Link
cites Diodorus Siculus, a Greek historian, who reports that the Egyptians
maintain that life first began in Egypt, and as proof of this they note
that mice are generated in vast numbers from the soil of their land.
Diodorus himself testifies, "Indeed, even in our day during the
inundations of Egypt, the generation of forms of animal life can clearly
be seen taking place in the pools which remain the longest, for, whenever
the river begun to recede and the sun has thoroughly dried the surface of
the slime, living animals, they say, take shape, some of them fully
formed, but some only half so and still actually united with the very
Link then adds a footnote to Diodorus' account. He writes, "The springmaus
(dipus jaculus), which dwells in Upper Egypt and is characterized by very
short forelegs, looks as though it is a creature that is not yet fully
This "springmaus" is the jerboa. The jerboa belongs to a family of tiny to
large rodents that have very small forelegs (which they hold against their
bodies) and long back legs for jumping and dig burrows in which they
sleep. One of the three small subfamilies is known as Dipodinae and it
includes the genus Jaculus. This is the dipus jaculus mentioned by Link.
It is clear that Link himself, who lived in the nineteenth century and was
very familiar with the jerboa, did not believe that it or any other animal
grows from the ground. Rather, he is saying that this creature may be the
source of the Egyptian myth. Because the jerboa's forelegs are not visible
while it is jumping, it appears to be a two-legged mouse (which is why it
is called "dipus," or "two legs"). One who observes it sitting on the
ground or jumping in the air, it appears that the two hind-legs are
actually the forelegs, and the rear part of the mouse has not yet been
Rav Aryeh Carmell suggests that the creature referred to is simply a mole.
A dead mole, with clods of earth attached to its body, would appear to
have grown from the ground. Alternatively, as it emerges from the earth,
people could mistakenly believe that it is growing from the earth.
(However, the people in the time of the Gemara seem to have been familiar
with moles and burrowing creatures, and thus people would not have been
mistaken about the nature of such a creature; see Moed Katan 6b.)
Perhaps we may suggest that the myth developed from the existence of
certain species of small amphibians and rodents that burrow in the mud and
entomb themselves in a cocoon of solidified mud during the dry season.
Entombed, the creatures' bodily functions nearly cease and they remain
entirely motionless until the first rain, at which point they shed their
cocoon. A creature photographed in such a state unquestionably appears as
a clod of earth, and while leaving its cocoon it certainly looks as though
it is half-earth and half-creature. One such animal is the burrowing frog,
which lives in arid regions and deserts. At the start of a long dry spell,
when the pools from the last rainstorms are in the last stages of
evaporation, the frog buries itself up to twelve inches deep in the mud.
There it settles into a state of suspended animation, with its breathing
and heartbeat slowing to a rate just sufficient to keep it alive. After
about two weeks, the outer layers of the frog's skin detach and meld
together into a membrane that is fully waterproof apart from two tiny
tubes to the frog's nostrils. The frog can survive in this state amidst
desert drought for many years. Then, when the rainfall finally comes and
turns the sand into mud, the frog breaks out if its bag and emerges upon
the surface, appearing to have grown from the mud.
If this is indeed the case, such a creature is the prime proof for
Techiyas ha'Mesim. It first entered a state of suspended animation that
can be likened to death -- in fact, it might even be considered inanimate
Halachically while in that state -- and then it was "revived" and
"returned to life." Even if the Chachamim were aware of the true
circumstances surrounding this creature, they would have cited it as a
proof for Techiyas ha'Mesim, and discussed its status regarding Tum'ah and
Taharah. (M. Kornfeld)
(c) RAV SAMSON RAPHAEL HIRSCH has an enlightening approach to the subject
of how to understand statements like these in the Gemara in light of
modern science. In his essay entitled, "Trusting the Torah's Sages" (a
letter written in 1876 to Rav Pinchas M. E. Wechsler, published in 1976 in
the Jerusalem journal Hama'ayan, chapter 4), he writes the following:
"Imagine if a scholar such as Humboldt had lived in their times and had
traveled to the ends of the world for his biological investigations. If
upon his return he would report that in some distant land there is a
humanoid creature growing from the ground or that he had found mice that
had been generated from the soil and had in fact seen a mouse that was
half-earth and half-flesh and his report was accepted by the world as
true, would we not expect Chazal to discuss the Torah aspects that apply
to these instances? What laws of Tum'ah and Taharah apply to these
creatures? Or would we expect them to go on long journeys to find out
whether what the world has accepted is really true?
Rav Hirsch explains that the Chachamim were simply giving a ruling for a
case that was presented to them. They did not take it upon themselves to
verify whether or not such creatures existed, just as the Torah scholars
of Rav Hirsch's day would readily accept the testimony of Alexander von
Humboldt, a famous German naturalist. The same is certainly true with
regard to the proof to Techiyas ha'Mesim that our Gemara brings. The fact
that the people who lived at the times of the Amora'im had no trouble
accepting the fact that an animal can form from a clod of earth, served as
a perfect way for the Amora'im to prove to their contemporaries that
Techiyas ha'Mesim is not too great a stretch of the imagination.
"And if, as we see things today, these instances are considered fiction,
can Chazal be blamed for ideas that were accepted by the naturalists of
their times? And this is what really happened. These statements are to be
found in the works of Pliny, who lived in Rome at the time the second Beis
ha'Mikdash was destroyed, and who collected in his books on nature all
that was well-known and accepted in his day."
OPINIONS: The Gemara quotes the Beraisa in which Rebbi Shimon says that
there are three types of Tum'ah of Mes that are Metamei in two ways out of
the three ways that Tum'ah can be transferred -- Ohel, Maga, and Masa. One
of these types of Tum'ah is the Tum'ah of "Golel" and "Dofek" (see
Background to the Daf) which are Metamei through Ohel and Maga, but not
through Masa. What is the source that Golel and Dofek are not Metamei
7) THE "TUM'AH" OF THE EGGS OF "SHERATZIM"
(a) RASHI (DH Golel) explains that according to the view that the Tum'os
of Golel and Dofek are Halachos l'Moshe mi'Sinai, the law that the Tum'as
is not transferred through Masa is also a Halachah l'Moshe mi'Sinai.
However, Rashi gives no source for why they are not Metamei through Masa
according to the view that derives the laws of Golel and Dofek from verses
in the Torah.
(b) TOSFOS (DH Golel) explains that in order for a Tum'ah to be
transferred through any means (such as Ohel, Maga, or Masa), there must be
a source in the Torah for that form of transferal of Tum'ah. Accordingly,
the verse "v'Chol Asher Yiga Al Penei ha'Sadeh" (Bamidbar 19:16) teaches
that Golel and Dofek are Metamei through Ohel, and the word "Yiga" teaches
that they are Metamei through Maga. Since there is no source in the Torah
for Tum'as Masa of Golel and Dofek, they are not Metamei through Masa.
(c) Perhaps we may suggest a logical source for the lack of Tum'as Masa of
Golel and Dofek. The Tum'ah of Golel is directly related to its location
(as a coffin-cover, grave-marker, or vault-stopper, as described in
Background to the Daf). When it is even slightly moved ("Masa"), it is no
longer serving the purpose of a Golel, and thus it is not Metamei until it
is replaced. (The Tosefta mentions an opinion that a Golel that is moved
from its original place is Tahor.) (M. Kornfeld)
QUESTION: The Gemara derives from the verse, "ha'Sharetz" (Vayikra 11:31),
that once a Sheretz has begun to form in its egg, it is Metamei.
However, the Gemara earlier (64a) assumes that one is liable for eating a
Sheretz from the point at which the Sheretz starts to form in its egg. The
Gemara there understands that this is obvious, and no verse is necessary
to prove it. Why, then, does the Gemara here need a verse to prove that a
Sheretz is Metamei from the time that it begins to form in the egg?
(TOSFOS DH Yachol)
(a) TOSFOS explains that with regard to the prohibition against *eating* a
Sheretz, a Sheretz becomes prohibited from the moment that it can be
defined as a "Sheretz," which is the moment that it begins to form in its
egg. In contrast, we might have thought that in order to be Metamei, the
Sheretz must not only be identifiable as a Sheretz, must it also must be
identifiable as a specific *type* of Sheretz, such as an Achbar. When a
Sheretz begins to form, it is identifiable as a Sheretz, but it cannot yet
be called an Achbar! Therefore, it is necessary for the verse to teach
that such a Sheretz nevertheless is Metamei.
(b) Tosfos answers further that the verse regarding the ability of a
Sheretz to be Metamei in its egg is the source from which we learn that
the prohibition against eating a Sheretz applies from that moment as well.