(Mishnah): There are five Tamei colors of blood -- red, black, like the radiance of saffron, like water on earth, and like mixed wine. (These will be explained);

Beis Shamai is Metamei also blood like Meimei Tilsan (water in which fenugreek was soaked) or like juice that exudes from roasting meat;

Beis Hillel is Metaher these.

Akavya ben Mehalalel is Metamei Yarok. (Almost all Rishonim say that (plain) Yarok is yellow. Green is called Yarok k'Karsi (like leeks). Me'iri - Yarok is green, but all are Metamei yellow);

Chachamim are Metaher.

R. Meir says, (even) if a Yarok Kesem is not Tamei, the blood is a liquid (this will be explained);

R. Yosi says, it is neither.

Red is like blood of a wound. Black is like Cheres (vitriol, used to make ink);

Anything more Amuk (Rashi - dark; R. Chananel - light) than Cheres is Tamei. Anything more Dehah ((R. Chananel - much) lighter) than it is Tahor.

The other colors referred to are choice leaves of saffron (this will be explained), water poured on earth of Beis Kerem, and two measures of water mixed with one measure of Sharoni wine.

(Gemara) Question: What is the source that there are Tahor colors of blood? Perhaps all colors are Tamei!

Answer (R. Chama bar Yosef): "Ki Yipalei... Bein Dam l'Dam" refers to (a Zaken Mamrei arguing with the Sanhedrin about) a question of Tahor Dam or Tamei Dam.

Question: If so, will you say that "Bein Nega l'Nega" refers to an argument about a type of Tzara'as that is Tahor?!

Suggestion: Yes! "Kulo Hafach Lavan Tahor Hu." (If Tzara'as spreads and covers the entire person, he is Tahor.)

Rejection: That is not called Tzara'as. It is Bohak (a Tahor paling of the skin).

Rather, "Bein Nega l'Nega" must refer to Tzara'as of people, houses and garments. All are Teme'im;

Likewise, "Bein Dam l'Dam" refers to blood of Nidah, birth or Zivah. All are Teme'im!

Answer: Regarding Tzara'as, we can explain what they argue about:

Regarding Tzara'as of people, they argue as R. Yehoshua and Chachamim do:

(Mishnah): If Baheres (a white appearance on the skin) preceded the white hair, he is (absolutely) Tamei. If the white hair came first, he is Tahor (i.e. only Musgar);

If we are in Safek which came first, he is Tamei;

R. Yehoshua says, Kehah.

Question: What does this mean?

Answer (Rabah): It is as if the Tzara'as became weaker. He is Tahor.

Regarding Tzara'as of houses, they argue as R. Elazar bar Shimon and Chachamim do;

(Mishnah - R. Elazar b'Rebbi Shimon): A house is Tamei only if there are appearances (of Tzara'as) the size of a Gris on each of two stones that touch in the corner. (The appearances must touch each other.)

Question: What is his reason?

Answer: It says "Kir" and it also says "Kiros" refers to a wall that is like two walls, i.e. the corner.

Regarding Tzara'as of garments, they argue as R. Nasan and Chachamim do:

(Beraisa - R. Nasan ben Avtulmus) Question: What is the source that if Tzara'as spreads and covers the entire garment, it is Tahor?

Answer: It says Karachas and Gabachas regarding people, and also regarding garments;

Just like when Tzara'as spreads and covers an entire person, he is Tahor, also regarding garments.

Summation of answer: If all blood were Tamei, what could they argue about?! (Yerushalmi, cited in Meromei Sadeh - it does not say "Bein Dam v'Dam," rather, "Bein Dam l'Dam," which connotes discernment between different appearances of blood.)

Question: What is the source that these colors are Tamei, and others are Tehorim?

Answer (R. Avahu): "Va'Yir'u Mo'av... ha'Mayim Adumim ka'Dam" -teaches that blood is red.

Question: We should say that only the very reddest is Tamei!

Answer (R. Avahu): It says "Dameha" (plural, teaching two), and again "Dameha," making four in all.

Question (Mishnah): There are five Tamei colors.

Answer (R. Chanina): Black blood was red, just it was stricken.

Support (Beraisa): Black is like Cheres. More Amuk than this is Tamei, and more Dehah is Tahor, even if it is blue.

The blood is not black from the beginning. It becomes black after leaving the body.

(Mishnah - Beis Shamai): Also the color of Meimei Tilsan.

Question: Does Beis Shamai not learn from "Dameha... Dameha"?!

Answer #1: That is correct. (They learn two more colors from somewhere else.)

Answer #2: R. Chanina taught that black blood was red, just it was stricken. Likewise, the extra colors of Beis Shamai are stricken forms of red (or another of the four colors).

(Mishnah - Beis Hillel): These are Tahor.

Question: This is like the first Tana!

Answer: The first Tana considers them Safek Tamei. Beis Hillel is Metaher them completely.

(Mishnah - Akavya ben Mehalalel): Yarok (we will call this yellow, like most Meforshim) is Tamei.

Question: Does Akavya not learn from "Dameha... Dameha"?

Answer #1: That is correct. (He learns another color from elsewhere).

Answer #2: Yellow is a stricken form of one of the four colors.

(Mishnah - Chachamim): It is Tahor.

Question: This is like the first Tana!

Answer: The first Tana holds that yellow is Safek Tamei. Chachamim hold that it is definitely Tahor.

(Mishnah - R. Meir): (Even) if a yellow Kesem is not Tamei, the blood is a liquid.

(R. Yochanan): R. Meir holds like Akavya, that yellow is Tamei;

Explanation #1: He told Chachamim: Granted, a yellow Kesem is not Tamei. (Since yellow blood is rare, we are not concerned lest it came from her. Tosfos - alternatively, yellow blood is Tamei only mid'Rabanan and the Rabbinic decree of Kesamim does not apply to it);

However, you should agree that when we know that yellow blood came from her, she is a Nidah!

Rejection (Mishnah - R. Meir): If a yellow Kesem is not Tamei, the blood is a liquid;

According to R. Yochanan, it should say "(even) if a yellow Kesem is not Tamei, yellow blood is"!

Explanation #2: Rather, he told them: granted, if her first sighting of blood is yellow, it is (not Dam Nidah, it is) Tahor;

However, if she first saw red blood (she is a Nidah.) If she later sees yellow blood, the blood is Tamei like her urine and other bodily fluids!

Chachamim say, only fluids that accumulate before coming out (such as urine) are Teme'im, but not (Tahor colors of) blood, for it drips out right away!

Rejection: Chachamim's logic is sound. R. Meir would not argue with it!

Explanation #3: Rather, R. Meir said 'you should agree that yellow blood is Machshir.' (If it touches food, the food can be Mekabel Tum'ah);

Chachamim argue. We learn that blood is considered one of the seven liquids that are Machshir from "v'Dam Chalalim Yishteh." Her blood is not Dam Chalalim (of a corpse)!

Rejection: R. Meir would not argue with this!

Explanation #4: R. Meir learns from a Gezeirah Shavah. It says "Shelachayich Pardes Rimonim," and it says "v'Shole'ach Mayim Al Pnei Chutzos." The same blood that sends women from their husbands is equated to water. (It is Machshir. Tosfos ha'Rosh - since another source teaches that Dam Nidah is Machshir, the Gezeirah Shavah teaches that yellow blood is Machshir.)

Chachamim argue. A Chacham can make a Kal va'Chomer by himself, but he cannot learn a Gezeirah Shavah without a tradition from Moshe from Sinai.

(Mishnah - R. Yosi): It is neither.

Question: This is like the first Tana!

Answer: The Mishnah teaches that the first Tana is R. Yosi. One who says a Halachah in the name of its author brings redemption to the world.

(Mishnah): Red is like blood of a wound.

Question: What does this mean?

Answer #1 (Rav Yehudah): It is like blood of a slaughtered ox.

Question: Why didn't the Tana say 'like blood of Shechitah'?

Answer: That would imply like any blood of Shechitah;

'Blood of a wound' connotes the first blood that exudes from the incision.

Answer #2 (Ula): It is like blood of a bird that is Chayah.

Question: Does he say "Chayah" to denote that it is alive, or that it is healthy?

This question is not resolved.

Answer #3 (R. Zeira): It is like blood of a head louse.

Question (Mishnah): If a woman killed a louse and later saw a Kesem, she may be Toleh on the louse (attribute the Kesem to its blood).

Suggestion: She can attribute the blood to any louse, i.e. the blood of all lice is a Tamei shade of red!

Answer: No, she may be Toleh only on a head louse.

Answer #4 (Ami Vardina'ah): It is like the blood of the pinky if it was bruised, healed and bruised again;

It must be the smallest finger of a bachelor less than 20.

Question (Mishnah): She is Toleh on her son or husband (if he has a wound).

Her husband is not a bachelor, yet she can be Toleh on him! (This shows that his blood resembles Dam Nidah.)

Answer (Rav Nachman bar Yitzchak): The case is, her husband (is under 20, and) performed Chupah, but did not yet have Bi'ah with her. (Therefore, his blood still resembles Dam Nidah).

Answer #5 (Rav Nachman): It is like blood of bloodletting.

Question (Beraisa): Cases occurred in which R. Meir was Toleh on a bandage, and Rebbi was Toleh on sycamore sap.

Suggestion: They were Toleh red Kesamim on these. (This shows that they need not be so close to red. This is unlike all the Amora'im!)

Answer: No, the Kesamim were other colors.