1) THE MONETARY ELEMENT IN A NEDER
QUESTION: The Mishnah states that a Neder made through inference is a valid Neder. If one says, "That which I eat from you is not Chulin (la'Chulin, or Lo Chulin)," the Neder is valid because the positive ("Korban") may be inferred from the negative ("not Chulin"). The Gemara says that the Mishnah is not in accordance with the view of Rebbi Meir who maintains that converse inferences cannot be made from a person's speech; he does not agree with the principle of "Michlal Lav Atah Shome'a Hen."
The RAN points out that the Gemara in Shevuos says that Rebbi Meir argues only in cases of Mamon, monetary matters. Rebbi Meir agrees, however, that "Michlal Lav Atah Shome'a Hen" applies in cases of Isur. Why, then, in cases of Neder does he not apply "Michlal Lav Atah Shome'a Hen," if a Neder is an Isur?
The Ran answers that a Neder is an Isur which has a monetary component. The Gemara in Shevuos says that Rebbi Meir also argues in cases of Isurim which have elements of Mamon in them. A Neder is considered an Isur with a monetary element because through a Neder a person creates an Isur on an object which has monetary value; his Neder restricts the usage of the object with monetary value. This is also the view of TOSFOS here.
Apparently, the reason why Rebbi Meir agrees that "Michlal Lav Atah Shome'a Hen" applies in cases of Isur is that an Isur is more severe than a matter of Mamon, and therefore a person is more careful with his words (and he means what he says). Why, then, does Rebbi Meir maintain that "Michlal Lav Atah Shome'a Hen" does not apply in cases of Isur that involve money? The fact that there is an issue of money involved does not detract from the fact that it is still a case of Isur. There is no reason for a person to be less careful just because the Isur involves money as well.
ANSWER: It must be that Rebbi Meir agrees that "Michlal Lav Atah Shome'a Hen" applies in cases of Isur for a different reason. Perhaps Rebbi Meir generally considers a statement made in the negative ("Lav") as questionable whether the person had in mind the converse positive ("Hen"). In such a case of doubt, the Chachamim rule stringently in matters of Isur and assume that the person did mean the converse, and the Isur takes effect. If the Isur also involves money (such as the case of a Sotah, who stands to lose her Kesuvah money if she does not answer unequivocally that she is innocent, and in the case of Shevu'as ha'Edus, in which case the litigant stands to lose money if the witnesses do not clearly state that they do not know testimony for him), with regard to the money involved the negative statement is not to be understood stringently (and it is not interpreted to mean the converse positive), because with regard to money the law applies that out of doubt (mi'Safek) a person does not pay money until it is proven that he must pay. Hence, his negative statement is interpreted leniently. In the case of Nedarim, too, since he is making the object Asur, and the Isur affects his use of the monetary value of the object, his statement is interpreted leniently and it is assumed that he is not making the object inaccessible to himself.
RABEINU AVRAHAM MIN HA'HAR asks that it is clear from the words of the Ran (16a, DH Shevu'ah) that only a Neder -- which is an Isur Cheftza (an Isur which takes effect on the object and not on the person) -- is considered an Isur that contains a monetary element. A Shevu'ah, in contrast, is considered a normal Isur, to which Rebbi Meir agrees that "Michlal Lav Atah Shome'a Hen" applies. If, however, the determining factor is whether a monetary element is involved, when a person prohibits an object with a Shevu'ah (by prohibiting himself from that object) he loses access to that object just as he loses access to it when he makes a Neder. What difference does it make if an Isur Gavra or an Isur Cheftza prohibits him from benefiting from the object?
The Ran apparently is not bothered by this question because in the case of a Shevu'ah, the object is accessible but there is a "lion upon it." That is, the "lion" is the Isur Shevu'ah which he created, which makes the object inaccessible to him. The monetary value of the object is considered to be within his reach, but an external factor impedes his access to it. When a person prohibits himself from an object with a Shevu'ah, he does not address the object itself, but rather he focuses what he will or will not do. Accordingly, he does not relate to the object's monetary value to him, but to his own permissibility or lack thereof to do something. In contrast, when a person prohibits an object with a Neder and makes the object off-limits to him, he relates to the object in terms of its monetary value.
Why, though, is the Halachah lenient in a case of a doubtful statement of a Neder? The Gemara (18b) teaches that in a case of a doubtful Neder, the general principle of "Stam Nedarim l'Hachmir" applies and the Neder takes effect. If one's negative ("Lav") statement is viewed as a doubtful statement, why does the Neder not take effect? The principle of "Stam Nedarim l'Hachmir" should apply and the Neder should take effect out of doubt!
The answer is that "Stam Nedarim l'Hachmir" applies only when a person makes a statement like, "This object is Cherem," and it is not known whether he means the type of Cherem which is Asur (Chermei Bedek ha'Bayis) or the type of Cherem which is Mutar (Chermei Kohanim). If he means Chermei Kohanim, his statement is meaningless. There is no point in comparing an object to Chermei Kohanim; he could have remained quiet and said nothing, as his statement provides no new information (ROSH). The fact that he was not quiet and made a statement about the object implies that he intended to compare the object to the type of Cherem which is Asur, and that he meant to make a Neder. In contrast, when one makes a statement in the negative form ("This object is not Chulin") and not in the positive form ("This item is Korban"), his statement does make sense; he means that the object is not Mutar. It is an informative statement in its own right, and the only question is whether the converse may be inferred from it. Since the statement itself conveys a message, it cannot be assumed that he intends to make a Neder. Accordingly, the case is one of a "Safek Mamon" and the Halachah is lenient.