QUESTION: After the Gemara derives the source for the concept of Chazakah from the verses which discuss the Bayis ha'Menuga (Vayikra 14:38), the Gemara inquires about the source in the Torah for the concept of Rov.

TOSFOS (DH Mena Ha Milsa) is bothered by the Gemara's question. There is a rule that in a case in which a Rov counters a Chazakah, the Rov prevails (Yevamos 119b, Kidushin 80a, Nidah 18b). If it is obvious to the Gemara that a Rov is more powerful than a Chazakah, then once there is a source for the concept of Chazakah, why is a source needed for the concept of Rov?

(a) TOSFOS answers that the Gemara seeks a source for Rov according to the opinion of Rav Acha bar Yakov, who maintains (10b) that the verses which discuss the Bayis ha'Menuga provide no proof for the concept of Chazakah. Since, according to Rav Acha, no verse teaches that a Chazakah is an effective method for resolving a doubt, the Gemara needs to find a source for the concept of Rov.

The MAHARSHA adds that according to Rav Acha bar Yakov, the source for the concept of Chazakah must be a Halachah l'Moshe mi'Sinai.

(b) Alternatively, Tosfos answers in the name of RABEINU CHAIM that the question is based on a flawed premise. Rov prevails over a Chazakah not because of a logical reason, but because the Torah teaches so when it teaches the concept of Rov. The source for Rov is the Halachah that a Parah Adumah is valid and there is no need to be concerned that it might be a Tereifah, since most animals are not Tereifos. This source also teaches the power of a Rov. The Parah Adumah is used to be Metaher people who have a Chazakah of being Tamei. This effect of the Parah Adumah is based on the Rov that permits the use of the animal without concern that it is a Tereifah. Accordingly, a Rov is powerful enough to override a Chazakah.

The SHITAH MEKUBETZES has difficulty with this proof. If the actual Parah Adumah itself would contain both a Chazakah and a Rov, then Rabeinu Chaim's answer would be appropriate. However, in the case of the Parah Adumah, the Rov is based in the animal (that it is not a Tereifah), and the Chazakah is in the person (that he is Tamei). Once the Parah Adumah is slaughtered and declared valid, the ashes of the Parah Adumah have the ability to remove the Chezkas Tum'ah from a Tamei person. However, this does not teach that when a Rov and a Chazakah conflict in determining one's status, the Rov prevails.

(c) RABEINU PERETZ and the RASHBA answer that the rule that a Rov overrides a Chazakah is known only once there is a source for Rov in the Torah. If there would be no source in the verse for Rov, then a Chazakah would prevail over a Rov.

The Shitah Mekubetzes has difficulty with this answer as well. Since the only factor that determines that a Rov is more powerful than a Chazakah is logic, what difference does it make if there is no source for Rov in the verse, if logically is stronger than Chazakah?

The Shitah Mekubetzes explains that it is possible that the answer to this question is based on the logic of "Dayo la'Ba Min ha'Din Liheyos ka'Nidon" -- it is sufficient to give the Halachah learned from a Kal va'Chomer the exact status of the Halachah from which it is derived, and not a greater degree of stringency, even though there may be reason for it to be more stringent. Similarly, if the only source for Rov would be from the fact that there is a source for Chazakah, then it would not be possible to give Rov more power than a Chazakah, even though there are logical grounds to do so. In a case in which a Rov counters a Chazakah, the Halachah would have to follow the explicit concept of Chazakah and not the concept of Rov. This is why an explicit source in the verse is needed for the concept of Rov. (Y. MONTROSE)

QUESTION: Rabah bar Rav Shila says that the principle of Rov is derived from the laws of the Parah Adumah. The Torah requires that the Parah Adumah be both slaughtered and burned while it is a Kosher animal and not a Tereifah, and yet the Torah permits the use of the animal without concern that it is a Tereifah, since most animals are not Tereifos. This is the source that in a case of doubt, the Halachah follows the Rov.

Tosfos (DH Asya) asks that perhaps the reason why the Torah is lenient in the case of a Parah Adumah is not because of Rov, but because there is a Chazakah that the animal is not a Tereifah, since the animal has already lived for twelve months. (A Tereifah is defined as an animal that cannot live for twelve months; see Chulin 42a.) Why, then, does the Gemara derive the source for Rov from the laws of the Parah Adumah?

ANSWER: TOSFOS explains that an object has a Chazakah only when there was one moment at which the status of the object was certain. If, at some point in time, it was known that an animal was not a Tereifah, then the fact that it lived for twelve months provides a Chazakah that now, too, it is not a Tereifah. However, a Chazakah cannot be created retroactively (after twelve months); the concept of Chazakah does not determine that since an animal has lived for twelve months, twelve months ago it was certainly not a Tereifah.

Tosfos derives a practical Halachah based on this answer. In a case in which cheese was made from the milk of an animal that was later slaughtered and found to be a Tereifah, there is no pre-existing "Chezkas Heter" that states that the animal was not a Tereifah at the time it was milked. Consequently, the cheese is prohibited.

The RASHBA quotes RABEINU YONAH and other Rishonim who disagree with the ruling of Tosfos. It is true that at this point in the Gemara, when the Gemara is attempting to prove the principle of Rov from the laws of Parah Adumah, the Gemara assumes that the animal has no Chazakah that it is not a Tereifah ("Chezkas she'Einah Tereifah"). According to the conclusion of the Gemara, however, after the Gemara has proven that Rov works, a Rov states that most animals are not Tereifos, and thus it may be assumed that this animal also was not a Tereifah at the time of the doubt (that is, at the time that it was milked). Rather, it is assumed that the animal became a Tereifah at the latest possible moment, the moment before it was slaughtered. (The Rishonim call this a "Chazakah ha'Ba'ah Machmas Rov.") Therefore, the cheese is Kosher, since it is assumed that the animal was not a Tereifah at the time it was milked. (Z. Wainstein)

QUESTION: The Gemara suggests several possible sources in the Torah for the principle of Rov. Some of the sources are from laws in the Torah that permit one to rely on the fact that most animals (the Rov) are not Tereifos, and thus one may eat or use an animal without concern that it is a Tereifah. One may eat an animal after Shechitah without being concerned that perhaps at the place where the knife cut there was a pre-existing hole rendering the animal a Tereifah. Similarly, one may offer a Korban Pesach, Eglah Arufah, Parah Adumah, and Se'ir ha'Mishtale'ach without concern that the animal is a Tereifah.

The Gemara here seems to contradict the opinion of the RAMBAM (Hilchos Avos ha'Tum'ah 16:1, Hilchos Tum'as Mes 9:12). The Rambam maintains that the rule of "Safek d'Oraisa l'Chumra" is mid'Rabanan. This means that the Torah itself permits an item that is not certainly forbidden, but about which there is a doubt, but the Chachamim enacted a decree that whenever there is a doubt regarding an Isur d'Oraisa, the item is forbidden. (See Insights to Chulin 9:6, Kidushin 73:1, Bava Metzia 7:1.)

According to the Rambam, what is the Gemara's proof that there is a source for Rov in the Torah? Perhaps indeed there remains a doubt about whether or not the animal is a Tereifah, but since it is only a doubt, the Torah permits one to eat a Safek Tereifah! It was only the Chachamim who enacted the Chumra not to eat a Safek Isur. According to the Rambam, how does the Gemara prove the concept of Rov from these laws of the Torah? (RASHBA, Kidushin 73a; see also Insights there.)

ANSWER: RAV SHIMON SHKOP (in SHA'AREI YOSHER 1:7) explains that even according to the Rambam, a Safek does not change an Isur into a Heter. If a person eats meat when he is in doubt about whether it is Kosher, and it is found to have been not Kosher, he has violated the prohibition against eating non-Kosher meat. Nevertheless, the Torah only prohibits one from performing an act when that act is certainly forbidden; when there is a doubt, the Torah allows one to perform the act, but "at one's own risk."

This explains the Gemara according to the Rambam. The fact that the Torah commands one to bring a Korban Pesach and does not require that one be concerned that it is a Tereifah is a valid source for the principle of Rov. Even if, as the Rambam rules, a Safek d'Oraisa is permitted mid'Oraisa, the Torah would never have commanded one to enter into the risk of eating a Tereifah. (Z. Wainstein)

QUESTION: Rav Acha bar Yakov says that the principle of Rov is derived from the laws of the Se'ir ha'Mishtale'ach. The Torah (Vayikra 16:7) requires that the two Se'irim brought on Yom Kippur be identical. This requirement teaches that the Se'ir ha'Mishtale'ach cannot be a Tereifah, just as the Se'ir la'Shem (which is offered as a Korban) cannot be a Tereifah. While the Se'ir la'Shem can be examined after it is slaughtered to ensure that it is not a Tereifah, how can the Se'ir ha'Mishtale'ach be examined? It is cast off of a cliff while alive, and there is no way to ensure that it is not a Tereifah. It must be that the concept of Rov applies, and since most animals are not Tereifos, it is assumed that the Se'ir ha'Mishtale'ach is also not a Tereifah.

However, the Gemara continues, "And if you ask what difference does it make if the Se'ir ha'Mishtale'ach is a Tereifah," and it answers that it does make a difference, because the Torah teaches that the Goral (lot) determines which is the Se'ir ha'Mishtale'ach only when both animals are fit to be the Se'ir la'Shem.

Why does the Gemara need a different source for the requirement that the Se'ir ha'Mishtale'ach not be a Tereifah? Why does the Gemara's previous reason, that the two goats must be identical, not suffice? (MAHARSHA, TIFERES YAKOV)

(a) The MAHARSHA answers that the Gemara's intention is to give an alternative source for the requirement that the Se'ir ha'Mishtale'ach not be a Tereifah, in case the verse (Vayikra 16:7) is needed to teach other Halachos (see Yoma 62a).

(b) The Gemara in Yoma (72a) teaches that the requirement that the two goats be identical is only l'Chatchilah. If the animals are not identical, then b'Di'eved they may be used. Accordingly, the intention of the Gemara here may be to ask, "What difference does it make if the Se'ir ha'Mishtale'ach is a Tereifah? Perhaps the requirement that it not be a Tereifah is only l'Chatchilah, but b'Di'eved a Se'ir ha'Mishtale'ach that is a Tereifah is valid, and there is no proof for the concept of Rov!" (M. KORNFELD)

QUESTION: Rav Mari says that the principle of Rov is derived from the fact that the Torah says that a person who hits his father is punished with death (Shemos 21:15). Why does Beis Din not suspect that the man he hit is not really his father, and therefore he is not deserving of death? It must be that Beis Din may rely on the Rov of "Rov Be'ilos Achar ha'Ba'al."

The Gemara in Kidushin (73a) discusses the Torah's prohibition against a Mamzer joining the "Kehal Hash-m" -- "congregation of Hash-m" (Devarim 23:3). The Gemara says that the Torah prohibits a Mamzer from joining a "Kehal Vadai" -- a Mamzer may not marry anyone whose pure lineage is certain, but a Mamzer may marry a person whose pure lineage is in doubt, such as a Shetuki or Asufi. According to the Gemara here, which understands that a person's paternal lineage is known only through a Rov, it is apparent that the Gemara's statement in Kidushin about a "Kehal Vadai" can mean only a congregation of people whose lineage is known to be pure only based on a Rov.

Based on the Gemara here and in Kidushin, the SHEV SHEMAITSA (2:15) questions the words of the SHITAH MEKUBETZES in Bava Metzia (6b). The Gemara in Bava Metzia (6b) discusses a case in which an animal that was already counted as the tenth animal for Ma'aser Behemah jumped back into the pen of uncounted animals and became lost among the other animals. The Halachah is that all of the animals become exempt from Ma'aser Behemah, because the Torah requires that Ma'aser Behemah be "Ma'aser Vadai" -- the tenth animal must be definitely Ma'aser for the other animals, and not Ma'aser out of doubt.

The Shitah Mekubetzes asks that the owner should be required to continue counting the animals and separating Ma'aser from them, because of Rov. There is a Rov that most animals in the pen did not leave the pen and are still obligated in Ma'aser Behemah. The Shitah Mekubetzes answers that whenever the Halachah requires that something be definite, Rov does not apply. The Shitah Mekubetzes explains that this is because a Rov is not a logical proof which determines the truth and facts about a situation ("Birur"). Rather, a Rov is the way in which one is to conduct himself in a case of doubt ("Hanhagah").

According to the Shitah Mekubetzes, how can there ever be a "Kehal Vadai," as the Gemara in Kidushin mentions? The Torah requires that there be a certainty about the person's lineage (in order to prohibit a Mamzer from marrying that person). If it is known that a person's lineage is pure only because of a Rov ("Rov Be'ilos Achar ha'Ba'al"), there should be no such thing as a "Kehal Vadai"!

(a) The SHEV SHEMAITSA answers that the Shitah Mekubetzes' explanation of how Rov functions applies only to one type of a Rov -- a "Ruba d'Isa Kaman."

This refers to a situation in which the Rov is physically present, as the Gemara earlier (11a) mentions. When there are two possibilities present (for example, the animal being counted for Ma'aser might be from those that were not yet counted, and it might be from those that were already counted), there is no reason to assume that one possibility occurred more than the other possibility (for example, that the animal came from one group and not from the other group). Both possibilities are equally as likely to have occurred. In such a case, a Rov dictates only how one should conduct himself; it does not determine the facts. Therefore, where the Torah requires a certainty, one cannot rely on a Rov.

In contrast, the principle of the Shitah Mekubetzes does not apply to a "Ruba d'Leisa Kaman." A "Ruba d'Leisa Kaman" is a majority in frequency -- something usually occurs in this manner. The majority is not present and countable, but is a predictable consequence of natural events, such as the Rov that "most animals are not Tereifos." This Rov is not present, but there nevertheless exists a fact that most animals are born healthy. The Shitah Mekubetzes agrees that this type of Rov does serve to clarify the facts; the statistical likelihood determines that this indeed is what happened. Consequently, the Rov that "Rov Be'ilos Achar ha'Ba'al," which is a "Ruba d'Leisa Kaman," is able to determine who is part of the "Kehal Vadai," since all fathers are assumed to be definitely the real fathers of their children.

The KEHILOS YAKOV (#7) writes that he never was able to understand the logic behind the Shev Shemaitsa's answer. The reality of a "Ruba d'Isa Kaman" is the same as the statistical determination of a "Ruba d'Leisa Kaman." Both types of Rov have the same chance of clarifying the reality in a situation of doubt! What difference is there between a situation which has physical representation of the statistics (Isa Kaman) and one which has statistical representation alone (Leisa Kaman)?

RAV ELIMELECH KORNFELD shlit'a suggests that the Shev Shemaitsa means that there is an intrinsic difference between the two types of Rov. In the case of the Rov in Bava Metzia (Ruba d'Isa Kaman), it is known for certain that an animal that was already counted has jumped back into the pen. The fact that most of the animals in the pen were not yet counted does not remove the doubt that each animal might be the one that jumped back into the pen. However, in the case of the Rov in Kidushin, where the Gemara determines a "Kehal Vadai" based on Rov (a Ruba d'Leisa Kaman), there is no evidence that there is even one person in the entire nation who is not really his father's son. Even if there would be such evidence, there would be no reason to assume that with regard to each particular person there is any doubt that the assumed father is not the real parent of his son. In a case in which there is no doubt present, the Shitah Mekubetzes would agree that a Rov creates a situation of "Kehal Vadai."

(b) REBBI AKIVA EIGER (Teshuvos 2:108) answers that the Shitah Mekubetzes agrees that when a Rov has been used to determine other Halachic matters that do not need a definite status (for example, in the case of the Rov that states that a father is the real parent of his son, the Rov also teaches that the father is obligated to perform a Bris Milah for his son, and that the son is obligated to honor his father, etc.), the Rov becomes a certainty. He proves this from the case of Ma'aser Behemah itself, as follows. According to the Shitah Mekubetzes, how can one ever perform the Mitzvah of Ma'aser Behemah when it is possible that there is an animal among those counted which is a Tereifah? The answer is that there is a Rov that most animals are not Tereifos. The fact that one relies on this Rov, despite the fact that Ma'aser Behemah must be Ma'aser Vadai, shows that even the Shitah Mekubetzes agrees that a Rov which establishes itself once turns into a Vadai.

A similar explanation is given by the HAFLA'AH in Kesuvos (15a). The Gemara teaches that Rov does not apply to cases of monetary judgments ("Ein Holchin b'Mamon Achar ha'Rov"; see Bava Kama 27b). However, there are many monetary cases in which it seems that the Halachah does follow a Rov. One example is the case of Ones u'Mefateh (rape and seduction), where the guilty man must pay a fine to the father of the girl. Since it is known that the girl's father is her real father only because of a Rov, why does the perpetrator not invoke the rule that Rov does not apply to monetary judgements and say that he does not owe money to the man claiming to be the girl's father? The Hafla'ah says that the reason apparently is that once a Rov is used, it is considered factual. However, the Hafla'ah adds that it appears that the Rishonim do not agree with this approach. (See Hafla'ah at length. See also Kehilos Yakov 7:3 for an additional answer.) (Y. MONTROSE)