1)

(a)We query Rebbi Yossi (who holds that Tum'ah Temunah is not Boka'as ve'Olah) from a Mishnah in Ohalos, which discusses a dog that ate Basar Meis and died on the threshold of a house with its neck inside the house. If the dog was still alive the house would remain Tahor - because Tum'ah Belu'ah inside a live animal is not Metamei (as we learned in the fourth Perek).

(b)According to Rebbi Meir, it depends upon whether the dog's neck is a Tefach thick or not - irrespective of the fact that the hole of the esophagus is not a Tefach thick.

(c)The minimum cubic Shi'ur that can transmit Tum'ah from one domain to another is - a square Tefach.

(d)We initially think that Rebbi Yossi, who says that 'We view the Tum'ah; within the lintel, the house is Tamei, outside, it is Tamei' - comes to argue with Rebbi Meir over where the dog's neck is less that a Tefach thick, where Rebbi Meir declares the house Tahor, whereas according to him, it is a question of where the Tum'ah is (if it if inside, then the house is Tamei).

2)

(a)According to Rebbi Elazar, the criterion is where the dog's mouth is. What he means is that - assuming that the Tum'ah is outside, then we go (not by where the mouth is, but) after where the back of the animal is, because that is where the Tum'ah was destined to leave the dog's body (like we learned above, regarding the cupboard [See Maharatz Chiyos]).

(b)Rebbi Yehudah ben Beseira maintains that, either way, the house is Tamei - because of the possibility that the Tum'ah might leave the dog by way of its mouth (in the event that it vomited it out).

(c)Rebbi Yossi's two rulings now appear to clash - because whereas in his earlier ruling, he maintained that Tum'ah Temunah is not Boka'as ve'Olah, here he seems to hold that it is.

3)

(a)Rava therefore explains that Rebbi Yossi argues with Rebbi Meir in two points - 1. That we do not go after the thickness of the neck, but after the hole of the esophagus, which must be a Tefach thick in order to transmit the Tum'ah into the house - 2. Even if it is, we do not consider the entire threshold part of the house (and therefore Tamei, but only the section that is within the lintel (and not the section that is outside). So that in fact, Rebbi Yossi is more lenient that Rebbi Meir, not like we thought at first.

(b)And we now explain his previous statement 'We view the Tum'ah, within the lintel, the house is Tamei, outside, it is Tamei' to mean that - unlike Rebbi Meir, who is not concerned as to which side of the lintel the dog's mouth is, Rebbi Yossi requires the mouth to be on the inside of the lintel for the house to become Tamei.

(c)Rav Acha b'rei de'Rava agrees with his father - and he actually amends Rebbi Yossi's statement to 'We view the hole (of the esophagus) of the Tum'ah ... ', thereby supporting his explanation.

4)

(a)We learned earlier that Rebbi Yossi refers to Ohel as Noge'a. The author of the Mishnah in Ohalos (which argues with Rebbi Yossi [see Tosfos DH 'Ma'an Tana] and) holds that Ohel and Noge'a do not combine is - Rebbi Shimon.

(b)When Rebbi Shimon speaks of three Tum'os that emanate from a Meis ('M'lo Tarvad Rekev, Etzem ki'Se'orah and Golel ve'Dofek), he cannot be providing us a comprehensive list of all Tum'os that emanate from a Meis - because there are many more (k'Zayis Basar, Shedrah ve'Gulgoles she'Lo Chasru, Rov Minyan ve'Rov Binyan), besides the three that he mentions).

(c)What he is saying is that - there are only three kinds of Tum'os to which only two out of the three branches of Tum'ah (Maga, Masa and Ohel) apply.

(d)All the other types of Tum'ah - are subject to all of them.

5)

(a)The branchof Tum'ah which does not pertain to ...

1. ... M'lo Tarvad Rekev is - Maga.

2. ... Etzem ki'Se'orah is - Ohel (both of which we already learned earlier).

(b)'M'lo Tarvad Rekev' is not subject to Maga - because since the particles of Rekev are not connected, it is governed by the principle Ein Noge'a ve'Chozer ve'Noge'a.

(c)When Rebbi Shimon says 've'Heichan Maga'o/Ohalo/Masa'o, be'Achad meihen', he means that - Maga ... applies to both of the other two.

(d)Rebbi Shimon argues with Rebbi Yossi in that - he lists M'lo Tarvad Rekev as not being subject to Maga (because he does not refer to Ohel as Maga), whereas Rebbi Yossi (on the previous Amud [who does]) specifically stated that M'lo Tar vad Rekev is subject to Maga too.

6)

(a)Golel is - the top-board of the coffin in which a Meis is buried, whereas Dofek is - one of the side-boards.

(b)Masa does not apply to Golel and Dofek - Halachah le'Moshe mi'Sinai (see also Tosfos DH 'Golel ve'Dofek').

7)

(a)With reference to the Din of Kulyas Neveilah in our Mishnah, the Beraisa learns from the the Pasuk in Shemini (in connection with Tum'as Neveilah) "ha'Noge'a be'Nivlasah Yitma", from ...

1. ... the word "be'Nivlasah" - 've'Lo be'Kulyah S'tumah' (that a closed bone is not Metamei).

2. ... the extra 'Yud' in the word "Yitma" that - as long as one can touch the marrow inside, it is Metamei (otherwise not).

(b)When Rav Papa asked Rava why, in that case ...

1. ... a Neveilah, which is covered with skin, is Metamei - he told him to go and see how many holes there are in the skin (the mouth, the nose, the eyes).

2. ... the kidney of a Neveilah, which is covered with Cheilev, is Metamei - he told him to go and see how many strips of flesh protrude from the Cheilev.

(c)The Cheilev is not Metamei - because we learn from the Pasuk in Tzav (in connection with Cheilev) "Ye'aseh le'*Chol* Melachah" that one may use the Cheilev of a Neveilah even for Hekdesh, in which case it must be Tahor.

8)

(a)Rav Oshaya asked whether the bone containing marrow will be Metamei if one had in mind to make a hole in it but did not yet do so - whether the absence of a hole is considered lacking the act of boring, or not.

(b)Rav Oshaya himself concluded that - it is and that the marrow is therefore not Metamei (see Shitah Mekubetzes).

9)

(a)According to our Mishnah, the egg of a Sheretz is Metamei if - a. a chick has begun to form inside it and b. it is holed.

(b)It is not Metamei when it has a shell - because a Shomer is only Metamei when the Tamei object is accessible, as we already learned.

(c)Even though most Sheratzim do not lay eggs - some, such as toads, lizards and snails, do.

(d)In the Pasuk in Shemini "Eileh ha'Temei'im lachembe'Sheretz, Kol ha'Noge'a bahem Yitma ... ", the Beraisa learns from the 'Hey' in "ha'Temei'im" that (among other things) the holed egg and thigh-bone of a Sheretz are Metamei; whereas the Tana learns from ...

1. ... the word "ha'Sheretz" the Tana learns that - the egg of a Sheretz, is only Metamei if, like the Sheretz itself, it has already fertilized. And ...

2. ... from the extra "Yud" in "Yitma", he extrapolates that - as we learned by a Neveilah, it is only Metamei if it can be touched

10)

(a)The hole the size of a hair is sufficient in this regard - because a hair is considered part of the person (so that when a person's hair touches something, it is as if their flesh is touching it.

(b)The Toras Kohanim learn from the Pasuk in Metzora ...

1. ... "ve'ha'Noge'a bi' Vesar ha'Zav (ve'Tamei ad ha'Arev)" that - the dirt that has accumulated on a Zav and the loose matted strands of hair (on his chest) do not render a Tahor person Tamei.

2. ... "ve'Chol asher Yiga bo ha'Zav (ve'Tamei ad ha'Arev)" that - if a Zav touches the dirt that has accumulated on a Tahor person and the loose matted strands of hair (on his chest), he remains Tahor.

(c)Whereas from "ve'Tamei" in both cases, we learn that - the hair and nails that are still attached to him are considered part of him regarding the current Halachah.

11)

(a)A creature that is half-mouse and half-earth is - one that is not born of a mother and father, but that has half grown (length-wise) from a worm-infested trash-heap.

(b)The Tana Kama of our Mishnah rules that someone who touches its flesh is Tamei; whereas if he touches the half that is still earth, he remains Tahor. According to Rebbi Yehudah - he becomes Tamei either way (seeing as it is only a matter of time until the earth part of it too, becomes part of the mouse [See also Tiferes Yisrael]).

(c)Rebbi Yehoshua ben Levi qualify the ruling in our Mishnah 'Achbor she'Chetzyo Basar ... ', declaring even the mouse part of it Tahor - by confining the Din in the Mishnah to where the mouse-half has fully grown. Otherwise, it does not render whoever touches it Tamei.

(d)According to the second Lashon, Rebbi Yehoshua ben Levi is referring to Rebbi Yehudah 'Af ha'Noge'a ba'Adamah sheke'Neged ha'Basar, Tamei' - but the Tana Kama will declare the person who touches it Tamei even if the mouse-half has not yet fully grown.

12)

(a)The only species of land animal that has no equivalent in the sea is - the weasel.

(b)Based on this piece of information, the Beraisa suggests that, just as, among the rodents, only a land-weasel is Tamei, so too, is only a land-mouse Tamei (but not a sea one). It counters this however - by learning from the Hekesh that just as whatever is called a weasel is Tamei, so too whatever is called a mouse is Tamei (even if it lives in the sea.

(c)The Tana therefore learns from the Pasuk in Shemini "ve'Zeh lachem ha'Tamei ba'Sheretz ha'Shoretz al ha'Aretz" from ...

1. ... the words "al ha'Aretz" that - only a land-Sheretz is Tamei.

2. ... the word "ha'Shoretz" (when it ought to have written ve'Zeh lachem ha'Tamei ba'Sheretz") - that even if the land Sheretz went down to the sea, died and touched something there, it still renders it Tamei.

3. ... "ba'Sheretz ha'Shoretz al ha'Aretz" - that even a mouse that is created from the ground and not born from parents, is Tamei.

(d)We cannot learn this from the Hekesh to weasel, by saying that just as whatever is called Chuldah is Tamei, so too, whatever is called Achbar is Tamei - because we can counter that and say that just as a weasel is born from parents, so too, is any Sheretz that is born from parents Tamei (but not one that is created from the ground).

13)

(a)A certain Rav suggested to Rava that perhaps "ba'Sheretz" comes to include a mouse that is created from the earth, and "ha'Shoretz", whatever crawls, even a sea-Sheretz. We would then learn from "al ha'Aretz" that - if the land-Sheretz went down to the sea, died and touched something there, it would not render it Tamei.

(b)Rava replied that - having included sea- Sheratzim in the realm of Tum'ah, it would be illogical to preclude a land-Sheretz from being Metamei in the sea.

(c)Rebbi Yitzchak bar Avdimi learns from "al ha'Aretz" 'Lehotzi Safek Tum'ah Tzafah' - if a dead land-Sheretz is floating on the water and there is a Safek whether it touched something, that article remains Tahor, even in a R'shus ha'Yachid, where we would otherwise apply the principle Safek Tum'ah bi'Reshus ha'Yachid, Tamei.

(d)The Beraisa uses the same word to preclude a sea-Sheretz - because the word "al ha'Aretz" is written twice.