Possibility #1: A Nazir shaves for it (a bone the size of a barley seed. This is a tradition,) for we do not learn it from the verse, which says "Al Kol Nafshos Mes Lo Yavo", which refers to something that is Metamei one who enters [the same Ohel]...

And [R. Akiva] wanted to learn a Revi'is of blood from it (the bone) from a Kal va'Chomer.

Possibility #2: Or, perhaps a Revi'is of blood is a tradition, that it is Metamei b'Ohel, for (R. Eliezer and R. Yehoshua) do not expound "Nafshos Mes" to teach about a Revi'is of blood;

Just the contrary! [Nafshos Mes] connotes a half Log of blood, which is the Shi'ur of two Mesim. (Even though most people have much more than a Revi'is of blood, a Revi'is is considered the minimal Shi'ur needed for life.) It is a tradition from Moshe from Sinai that a Revi'is is Metamei b'Ohel;

A bone the size of a barley seed is [the source of] the Kal va'Chomer. I.e. from a bone the size of a barley seed he wanted to learn that a Nazir shaves for Tum'as Ohel of a Revi'is of blood.

Explanation: "We do not learn a Kal va'Chomer from a tradition" means that from the strength of the stringency, which is a tradition from Moshe from Sinai, we cannot make a Kal va'Chomer.

The Gemara resolves [the question from a Beraisa that says that] a Revi'is of blood is [the source of] the Kal va'Chomer, and a bone the size of a barley seed is the tradition.

Explanation: It is not precise that he must say so. Rather, this [Korban] is offered for whoever [is obligated to bring it], and this is offered for whoever [needs to bring it].

Explanation: [The one who saw the Tum'ah thrown] was standing far away, so this was Safek Tum'ah in Reshus ha'Yachid. (If he was nearby, there were three together, so it would be Safek Tum'ah in Reshus ha'Rabim, which is Tahor.)

Question: If so, each should bring Korban Tum'ah Vadai, for every Safek Tum'ah in Reshus ha'Yachid [is considered Vadai Tamei, and] we burn Terumah due to it!

Answer: We learn from Sotah [that Safek Tum'ah in Reshus ha'Yachid is considered Vadai Tamei] only something that is possible, like Sotah. It is possible that she was defiled;

However, here we cannot be Metamei both of them [Vadai], for surely one of them is Tahor!

Question: If so, what was the question from the beginning "this is Safek Tum'ah in Reshus ha'Rabim", i.e. and both should bring Korban Taharah?

Also Safek Tum'ah in Reshus ha'Rabim, which we are Metaher, we learn from Sotah. We learn only something that could be. Here, surely one of them is Tamei!

Answer: [We have a different source that] Safek Tum'ah in Reshus ha'Rabim is Tahor. We do not learn this from Sotah. Rather, we establish each in his Chazakah;

In Chulin (10b), we learn from a verse to establish everything in its Chazakah.

Implied question: How can we establish each in his Chazakah? Surely one of them is Tamei!

Answer: Since we do not know [which is Tamei, we can we leave each in his Chazakah].

Implied question: In Chulin (9b), in the Havah Amina we said that [Safek Tum'ah in a Reshus ha'Rabim] is a tradition from Moshe from Sinai;

It connotes there that it is not due to Chazakah, rather, [we have a tradition] to learn from Sotah!

Answer: This is not the conclusion. Elsewhere (at the beginning of Nidah) it is explained at length.

Explanation: The simple meaning of the verse surely warns the Nikaf, for it says "the corners of your heads", i.e. the Nikaf.

However, since it says "Lo Sakifu", and did not write 'Lo Sukfu', the Lav was put also on the Makif, in order to equate the Makif to the Nikaf;

I.e. whenever the Nikaf is liable (if he would transgress, i.e. he is commanded), the Makif is liable.

Since a minor is not punishable, also one who is Makif him is not liable. Even a man may be Makif a minor.

Question: How does the Gemara know that Rav Ada bar Ahavah holds that an adult may be Makif a minor?

Answer: It infers this, since he asked Rav Huna "your [children], who is Makif them?" This implies "I hold that even an adult may be Makif a minor. However, according to you, who is Makif them?"

Implied question: [Since Rav Ada bar Ahavah himself holds that an adult may be Makif a minor], why did he curse him?

Answer: This was according to Rav Huna's reasoning, that an adult may not be Makif a minor. [Rav Ada] told him, since you forbid an adult to be Makif a minor, also a woman may not be Makif a minor;

Rav Ada does not expound that whoever is commanded about shaving is commanded about Hakafah, to exempt a woman who is Makif others.

Implied question: In Kidushin (35b) we expound like this! Whoever is commanded about shaving is commanded about Hakafah, to exempt a woman who is Nikaf!

Answer: Rav Ada agrees about that Drashah, because the simple meaning of the verse discusses the Nikaf;

However, this that Rav Huna expounds that "Lo Sakifu" applies also to the Makif, due to the wording Lo Sakifu (as opposed to Lo Sukfu), and equates it to shaving to exempt a woman who is Makif even an adult, surely Rav Ada argues with this;

[He holds that] we should equate Hakafah to shaving only for what the simple meaning of the verse discusses, e.g. the Nikaf.

Consequence: Now, they argue about two matters. Rav Huna holds that a woman may be Makif an adult or minor. Since she is not commanded about shaving, she is not commanded about Hakafah, both regarding being Nikaf, which the simple meaning of the verse discusses, and also regarding being Makif others;

Rav Ada bar Ahavah holds that surely a woman is exempt for being Nikaf, from the Hekesh of shaving, which the simple meaning of the verse discusses;

However, from the wording Lo Sakifu, which we expound to obligate also the Makif, also a woman is liable for it. She is not exempted from the Hekesh of shaving, since the simple meaning of the verse does not discuss this. She transgresses a Lav if she is Makif an adult.

Consequence (cont.): They argue also about a minor. Rav Huna holds that an adult who is Makif a minor is Chayav;

He holds that it is unreasonable to expound that because the Torah used the expression Lo Sakifu, which connotes the Makif and the Nikaf, therefore when the Nikaf is not commanded, also the Makif is exempt;

I.e. he holds that we do not learn from person to person.

Rav Ada holds that the Torah used this expression to teach that when the Nikaf is not commanded, also the Makif is exempt. Therefore, an adult who is Makif a minor is exempt.

Pesak: We hold like Rav Huna, that a woman may be Makif a minor, and the same applies to an adult.

Source: The Sugya in Bava Metzi'a (10b) is like him. (Some say that Yesh Shali'ach l'Devar Aveirah when the Shali'ach is not commanded, and some say so when the Shali'ach has no choice.) It says that these versions argue about a man who told a woman "be Makif a minor for me";

It says that the Shali'ach, i.e. the woman, is not commanded. This implies that she may be Makif a minor, like Rav Huna.

Inference: Since it discusses a woman, and not a man, this implies that a man who is Makif a minor is liable. Also this is like Rav Huna.

Implied question: Why didn't it say that they argue about a man who told a woman "be Makif an adult for me"? The Sugya is like Rav Huna [who permits even this]!

Answer: An adult would not consent to let her be Makif him, since he would be liable. However, a minor cannot protest, and he is not punishable.

Question: According to Rav Ada, who equates Makif to Nikaf, similarly we should equate Nikaf to Makif, and say that whenever the Makif is not liable, also the Nikaf is exempt, and it would be permitted to be Nikaf from a Nochri!

Answer: According to Rav Ada, we equate Makif to Nikaf, because the primary liability of the verse is written regarding the Nikaf. "Lo Sakifu Pe'as [Roshchem]" refers to the sideburns of the Nikaf;

This teaches that whenever the Nikaf is commanded, also the Makif is liable, and if the Nikaf is not commanded, the Makif is exempt;

However, when the Nikaf is commanded, even if the Makif is not liable, it is forbidden, for the verse comes to equate the Makif, which the expression Lo Sakifu connotes, to the Nikaf, which the simple meaning of the verse connotes;

However, it is unreasonable to equate the simple meaning of the verse itself, i.e. the Nikaf, to the Makif, which is connoted only from the expression Lo Sakifu, and not from the verse itself.

Proof: If not, why does [Tiglachas] Metzora override the Lav of Hakafah? It is possible to fulfill both of them, if a minor, woman or Nochri shaves him! Rather, this teaches like I explained.

Question: According to Rav Huna, who does not equate the Makif to the Nikaf, and even though the Nikaf is not commanded, the Makif is liable, if so, one who is Makif a Nochri should be liable, just like one who is Makif a minor!

Poor answer #1: We distinguish. A minor [is more stringent], because he will come to be obligated.

Objection: Now, he is not obligated! Rav Huna's reason does not depend on this, rather, because he does not equate the Makif to the Nikaf!

Answer #2 (R. Peretz): Since it says "Pe'as Roshchem", the verse refers to Yisrael, and not to Nochrim.

Question: This requires investigation, whether one who is Makif a woman is liable, like one who is Makif a minor, according to Rav Huna.

Explanation: We are thinking now that according to letter of the law, we do not need a verse to override the Lav of Hakafah, for [the Aseh of Tiglachas Metzora] overrides even a Lav ha'Shavah b'Chol;

Rather, it teaches that Hakafas Kol ha'Rosh is called Hakafah.