The Halachah is, one must cut the Kaneh below the place where the Kova starts to slope.

This is like the opinion that leaving over in the Chiti is Kosher.

Rav Nachman permitted cutting the Kaneh below the place where the Kova starts to slope.

Question (Rav Chanan bar Rav Ketina): This is not like Chachamim, nor like R. Yosi b'Rebbi Yehudah!

Answer (Rav Nachman): I rely on what I heard;

(R. Chiya bar Aba citing R. Yochanan): Below the place where the Kova starts to slope is Kosher.

(R. Yehoshua ben Levi): What Chachamim consider Hagramah is Kosher according to R. Yosi b'Rebbi Yehudah. What R. Yosi b'Rebbi Yehudah considers Hagramah is Kosher according to R. Chanina ben R. Antigonus.

Question: This is obvious (from our Mishnah and the Beraisa 18a-b)!

Answer: (R. Chanina ben Antignonus testified that Hagramah is valid.) One might have thought that this refers to the Hagramah of Chachamim. R. Yehoshua ben Levi teaches that he discusses and permits the Hagramah of R. Yosi b'Rebbi Yehudah (the first Tana).

The Halachah follows R. Chanina ben Antigonus, because Rav Nachman holds like him.

Version #1 (Rav Huna citing Rav Asi): Chachamim and R. Yosi b'Rebbi Yehudah argue when the first two thirds were slaughtered, and the last third was Hagramah (cut in a place invalid for Shechitah);

Chachamim require the entire Shechitah in the ring. R. Yosi requires only the majority.

If the first third was Hagramah, and the last two thirds were slaughtered, all agree that this is invalid, for the Shechitah is completed when the majority is cut, and at that point, there was more Hagramah than Shechitah.

Question (Rav Chisda): Just the opposite! They argue when the first third was Hagramah, and the last two thirds were slaughtered;

R. Yosi is Machshir, just like when half the Kaneh was cut (not through Shechitah) before the Shechitah;

Chachamim say that Hagramah is worse (than when half the Kaneh was already cut), for the Kaneh was not cut in the place of Shechitah.

If the first two thirds were slaughtered, and the last third was Hagramah, all agree that this is Kosher.

Support (Mishnah): (Cutting) the majority of a Siman is like (cutting) the whole Siman.

Rejection (Rav Yosef): Perhaps that Mishnah is only like R. Yosi b'Rebbi Yehudah!

Question (Abaye): Do Chachamim hold that the majority is not like the whole?!

Answer (Rav Yosef): I discuss only Shechitah, in which we find that Chachamim do not consider a majority like the whole.

Version #2 (Rav Huna citing Rav Asi): Chachamim and R. Yosi b'Rebbi Yehudah argue in a case that the first third was Hagramah, and the last two thirds were slaughtered;

R. Yosi is Machshir, like when half the Kaneh was cut before slaughtering;

Chachamim say that Hagramah is worse, for the Kaneh was not cut in the place of Shechitah.

If the first two thirds were slaughtered, and the last third was Hagramah, all are Machshir.

Support (Mishnah): (Cutting) the majority of a Siman is like (cutting) the whole Siman.

Rejection (Rav Chisda): Perhaps that Mishnah is only like R. Yosi b'Rebbi Yehudah!

Question (Rav Yosef): Do Chachamim hold that the majority is not like the whole?!

Answer (Rav Chisda): I discuss only Shechitah, in which we find that Chachamim do not consider a majority like the whole. (end of Version #2)

(Rav Huna citing Rav): If a third was Hagramah, a third was slaughtered, and the last third was Hagramah, this is Kosher;

This is because Shechitah is complete when the majority is cut, and this occurred in a valid place for Shechitah.

(Rav Yehudah citing Rav): This is Treifah, for the majority (of the majority of the Kaneh) must be (cut in a valid place for) Shechitah. (Here, a third was Hagramah, and a sixth was Shechitah/)

(Rav Yehudah citing Rav): If a third was slaughtered, a third was Hagramah, and the last third was slaughtered, this is Kosher;

(Rav Huna): This is Treifah.

Rav Yehudah was upset. 'Rav Huna says the opposite of whatever I say!'

Rav Huna: He has two reasons to be upset. Firstly, he heard from Rav, but I ruled (this latter case) from my own reasoning;

Also, the majority was slaughtered!

Rav Chisda: You should not retract, for then you will also have to retract your first teaching (which you heard from Rav).

In your first teaching, you were Machshir because the cut that made the majority (just past midway through the Kaneh) occurred in a valid place of Shechitah. In the second teaching, it occurred in an invalid place, so it is Treifah!

Question: If a third was slaughtered, a third was Hagramah, and the last third was slaughtered, what is the law?

Answer (Rav Nachman): This is like R. Elazar bar Minyomi's teaching!

(R. Elazar bar Minyomi): Shechitah like a comb (zigzag) is Kosher.

Rejection: Perhaps that is only when all the cutting was (in a valid place for) Shechitah.

Question: If so, obviously it is Kosher!

Answer: One might have thought that Shechitah must be exposed. R. Elazar teaches that this is not so.

Question (Rav Kahana): If a third was slaughtered, a third was Hagramah, and the last third was slaughtered, what is the law?

Answer (Rav Yehudah): It is Kosher.

Question (Rav Kahana): If a third was Hagramah, a third was slaughtered, and a third was Hagramah, what is the law?

Answer (Rav Yehudah): It is Treifah.

Question (Rav Kahana): If he slaughtered (started cutting) where there already was a hole. what is the law?

Answer (Rav Yehudah): It is Kosher.

Question (Rav Kahana): If he slaughtered and encountered a hole (which completed the majority of the Kaneh), what is the law?

Answer (Rav Yehudah): It is invalid.

R. Elazar said this in front of R. Yochanan.

R. Yochanan: What is the difference between the last two cases?

Answer (R. Elazar): If he slaughtered where there already was a hole, this is as if a Nochri began cutting, and a Yisrael finished the Shechitah;

If he slaughtered and encountered a hole, this is as if a Yisrael began cutting, and a Nochri finished the Shechitah.

R. Yochanan: You compare holes to slaughter of a Nochri (but this is wrong)!

Rava: R. Yochanan's objection is valid. When a Nochri finishes the Shechitah, it is invalid, since a Yisrael must finish it;

When there already was a hole, all that had to be cut was cut. What difference does it make where the hole was?!

(Mishnah): Shechitah from the side of the neck is Kosher. Melikah (the analog of Shechitah for a bird-offering, using the Kohen's fingernail) from the side of the neck is invalid;

Shechitah from the Oref (back of the head) is invalid. Melikah from the Oref is Kosher;

Shechitah from the (front of the) neck is Kosher. Melikah from the neck is invalid;

The entire neck is Kosher for Shechitah. The entire Oref is Kosher for Melikah.

What is Kosher for Shechitah is invalid for Melikah. What is Kosher for Melikah is invalid for Shechitah.

(Gemara) Question: What does Oref (in the Mishnah) refer to?

Suggestion: Iit is literally the back of the head opposite the face.

Rejection: not only Shechitah on the Oref is invalid. Even Melikah there is invalid!

Melikah must be "mi'Mul Arpo" (facing the Oref), but not the Oref itself.

Answer: Rather, it means facing (i.e. below) the Oref.

Support (Seifa): The entire Oref is Kosher for Melikah. (This implies that it is a large area.)

Question: What is the source (that this is the place for Melikah)?

Answer (Beraisa): "Mi'Mul Arpo" is opposite, facing the Oref.

We learn from "(Bnei Yisrael) are dwelling mi'Muli" (facing me)" and "they turned Oref to me, not faces."

Question: Why is the second verse needed?

Answer: This shows that Oref means the other side of the face.

(Bnei R. Chiya): One moves the Simanim behind the spine and does Melikah.

Version #1: They mean that also such a Melikah is Kosher.

Version #2: They mean that only such a Melikah is Kosher.

Support (for Version #1 - Mishnah): Shechitah from the Oref is invalid. Melikah from the Oref is Kosher.

If Melikah requires moving the Simanim behind the spine, such a Shechitah is Kosher also from the Oref!

Rather, Melikah is Kosher either way. The Mishnah discusses when he did not move them. (Therefore, Shechitah from the Oref is invalid.)