1)

(a)Rav Nachman Amar Rav rules that in a case where Reuven sees Shimon Shechting an animal - he may only eat from the animal if he watched him from beginning to end.

(b)The problem with this is that - Mah Nafshach, if Reuven knows that Shimon is conversant with the Dinim of Shechitah, then why should he have to witness the entire Shechitah, and if he knows that he is not, then Rav Yehudah's ruling is obvious.

(c)We even have difficulty in establishing Rav Nachman in a case where Reuven does not know whether Shimon is conversant with Hilchos Shechitah or not - because then, we ought to apply the principle Rov Metzuyin Eitzel Shechitah Mumchin hein (most people who are involved in Shechitah are experts).

2)

(a)This principle is based on a Beraisa. The Tana there rules that if someone ...

1. ... finds a Shechted chicken in the street - he may eat from it.

2. ... asks a Shali'ach to Shecht an animal for him, and he later finds that it has been Shechted - he may eat from it, too.

(b)We conclude that Rav Nachman is speaking in a case where Shimon is not conversant with the Dinim of Shechitah. Nevertheless, the Tana needs to stress that if Reuven did not observe the entire Shechitah, it is Pasul, to teach us that - even though Shimon Shechted one Si'man correctly, we do not assume that he Shechted the other one correctly, as well ...

(c)... because we suspect that whilst Shechting the second Si'man, he made Shehiyah or D'rasah.

3)

(a)When Rav Dimi bar Yosef asked Rav Nachman what the Din will be if Reuven asks Shimon to Shecht his animal and he later finds it Shechted, or if he asks him to separate Terumah and later finds it separated, he replied that the animal has a Chezkas Shechutah - but that the Terumah is not valid.

(b)The problem Rav Dimi bar Yosef had with Rav Nachman's seemingly contradictory rulings was that Mah Nafshach - if we assume that a Shali'ach performs his Shelichus, then the Terumah should be valid too, whereas if we don't, then the Shechitah ought not to be Kasher either.

(c)When the latter replied 'L'chi Teichal alah Kura de'Milcha', he meant to say (though in the form of a joke) that - when Rav Dimi would measure him a Kur of salt, he would answer his She'eilos.

(d)Even though, as Rav Nachman concluded, one cannot assume that a Shali'ach always fulfils his Shelichus, he nevertheless declared the Shechitah Kasher - because, even if someone other than the Shali'ach Shechted the animal, we will apply the principle Rov Metzuyin Eitzel Shechitah Mumchinein h.

(e)We cannot likewise say that perhaps somebody else separated the Terumah, and the T'rumah is valid - because of the principle that If Reuven separates Shimon's T'umah without permission, it is not valid.

4)

(a)In a case where someone lost his kid-goats or chickens, and found them Shechted, Rebbi Yehudah forbids them - whilst Rebbi Chanina b'no shel Rebbi Yossi ha'Gelili permits them.

(b)According to our initial understanding of Rebbi's statement, he prefers the ruling of ...

1. ... Rebbi Yehudah - where the Shechted animal is found in a trash-heap, and of ...

2. ... Rebbi Chanina b'no shel Rebbi Yossi ha'Gelili - where it is found in the house.

(c)And the basis of their Machlokes is - whether Rov Metzuyin Eitzel Shechitah Mumchin hein (Rebbi Chanina ... ) or not (Rebbi Yehudah).

5)

(a)Rav Nachman bar Yitzchak maintains that both Tana'im agree that Rov Metzuyin Eitzel Shechitah Mumchin hein. Consequently, if the Shechted animal is found ...

1. ... in the house - they will both declare it Kasher.

2. ... in a trash-heap in the street - they will both declare it T'reifah.

(b)And they are arguing - in a case where it is found in a trash-heap in the owner's house, and the basis of their Machlokes is - whether a person tends to throw his Neveilos on to the trash-heap in his house (Rebbi Yehudah), or not (Rebbi Chanina ... ).

(c)According to Rebbi Chanina b'no shel Rebbi Yossi ha'Gelili, a person would not throw his Neveilah on to the trash-heap in his house - because it stinks.

6)

(a)Initially, we now think that when Rebbi says that he prefers the ruling of ...

1. ... Rebbi Yehudah, where the Shechted animal is found in a trash-heap he means - a trash-heap in the house (since they both agree that if it is found in a trash-heap in the street, it is T'reifah).

2. ... Rebbi Chanina b'no shel Rebbi Yossi ha'Gelili, where it is found in the house, he means - in a trash-heap in the house (because they both agree that if it is found in the house S'tam, it is Kasher).

(b)The problem with this is - how Rebbi can hold like both conflicting opinions at one and the same time.

(c)We therefore amend Rebbi's statement. What he really means when he says that he prefers the ruling of ...

1. ... Rebbi Yehudah, where the Shechted animal is found in a trash-heap in the street is that - even Rebbi Chanina ... will agree with Rebbi Yehudah that if the animal is found in a trash-heap in the street it is T'reifah (since he only argues with him when it is found in a trash-heap in the house).

2. ... Rebbi Chanina b'no shel Rebbi Yossi ha'Gelili, where it is found in the house is that - even Rebbi Yehudah will agree with Rebbi Chanina ... that if the animal is found in the house it is Kasher (because he only argues with him when it is found in a trash-heap in the house).

7)

(a)Rava extrapolates from the fact that our Mishnah states (with regard to the Bedi'eved of a Chashu) Shema Yekalklu es Shechitasan (in the future), rather than Shema Kilk'lu ... (in the past) that - it is so common for them to spoil the Shechitah, that one should avoid allowing them to Shecht Lechatchilah, even with someone watching them as they Shecht.

(b)Our Mishnah concludes, ve'Chulan she'Shachtu va'Acherim Ro'in osam, Shechitasan Kesheirah. When Rava asks which Tana does not require Kavanah for Shechitah he is referring to - a Chashu (who do not have Da'as) Shechting whilst under supervision.

(c)Even though ve'Chulan she'Shachtu ... Shechitasan Kesheirah pertains to a Chashu, the Kashya above (with reference to this same statement) I Neima a'Chashu, alah Ka'i (ve'Im Shachtu Miba'i lei [implying that it does not]) means that - it cannot refer to a Chashu alone. It can however (and does), refer to a Chashu among others.

(d)Based on a statement of Oshaya Ze'ira from the b'nei Yeshivah, Rava therefore establishes the author as Rebbi Nasan. Oshaya Ze'ira stated in the name of Rebbi Nasan that - if someone throws a knife to stick into a wall and the knife Shechts whilst in flight, the Shechitah is Kasher.

8)

(a)The Chachamim - render a Shechitah without Kavanah to Shecht invalid.

(b)Rava commented on this Machlokes that - the Halachah is like Rebbi Nasan.

(c)We query this ruling from the ruling that requires Holachah and Hova'ah - that the knife cuts in both directions (away and back) by Shechitah.

(d)To reconcile Rava's ruling with that ruling, we establish the case - where the knife did indeed cut the animal's neck both before striking the wall, and on the rebound.

(e)Alternatively - we establish the case by a knife that is two neck-lengths, and which does not therefore require Holachah and Hova'ah, as we will see later.

9)

(a)Rebbi Chiya bar Aba cited Rebbi Yochanan, who asked whether a Katan has a Machshavah or not - if a Katan Shechts an Olah li'Shemah (without a supporting act that indicates what he is doing), is the Korban Kasher or not.

(b)When Rebbi Ami countered by asking why Rebbi Yochanan did not ask whether the Katan 'has a Ma'aseh' or not, he meant to ask - why Rebbi Yochanan did not ask whether, if a Katan supports his Machshavah with a Ma'aseh, it is valid or not...

(c)... such as where he transports an Olah from the south of the Azarah to the north, specifically stating that he was doing so in order to Shecht it as an Olah (see Tosfos DH 've'Tiba'i leih Ma'aseh').

(d)His Kashya is really based on a Mishnah in Keilim, where the Tana rules that - if children in play made a hole in an acorn, a pomegranate or a nut in order to fill it with earth, the acorn ... (see Rashash) is considered a K'li and is subject to Tum'ah ...

(e)... provided they explicitly stated why they made the hole.

10)

(a)With regard to Machshavah however - where a child found a nut-shell, and picked it up in order to measure earth with it, but without doing anything to it, the Mishnah rules that - the nutshell remains Tahor.

(b)Rebbi Ami's Kashya on Rebbi Yochanan is that - if he knew the Mishnah, then why did he need to ask whether a Katan has Machshavah, whereas if he did not, why did he not ask from Ma'aseh?

(c)Rebbi Chiya bar Aba answered that Rebbi Yochanan's She'eilah was - whether a Ma'aseh which indicates that the Katan knows what he is doing (such as moving an Olah from the south of the Azarah to the north) but which he did not verbalize, is considered a Ma'aseh or not.

(d)Such a Machshavah might ...

1. ... be considered as good as a Ma'aseh - because the Katan appears to know that Kodshei Kodshim must be Shechted in the north.

2. ... not be considered as good as a Ma'aseh - because of the possibility that he is moving it to the north for no particular reason, other than that he fancies moving it.