1) SALT AND WATER MIXED WITH DOUGH
QUESTION: Rav Ashi says that the spices mixed into a food, and the salt and water mixed with dough, are not Batel to the food or dough on Yom Tov. Consequently, the Techum of the owner of the spice, salt, or water is not Batel to the Techum of the owner of the food or dough. This is because the ingredient added to the food or dough is a "Davar she'Yesh Lo Matirin" -- one can simply wait until the following day to carry it out of the Techum of the other person, or one can simply eat it on Yom Tov within his own Techum.
The Gemara here seems to contradict a general rule in the laws of a "Davar she'Yesh Lo Matirin." The principle of "Davar she'Yesh Lo Matirin" applies only when the two items in the mixture are of the same type of food ("Min b'Mino"). Why does Rav Ashi apply this principle to this case, where the mixture is comprised of different types of food ("Min b'she'Eino Mino")? In this case, the spices, salt, and water indeed should be Batel to the food or dough.
ANSWERS:
(a) TOSFOS (DH Mishum) answers that the laws of Techumin are more stringent than the laws of other Isurim because of the monetary element involved. Money, or ownership, cannot become Batel to the ownership of someone else. An object's Techum stems, to a certain degree, from the ownership of the object (i.e., the object has the Techum of its owner). Even though the Gemara rejects Rebbi Aba's explanation (38b) that the reason why the Techum of the salt and water is not Batel to the Techum of the dough is because ownership cannot become Batel, Rav Ashi accepts that explanation when there is the additional reasoning of "Davar she'Yesh Lo Matirin."
(b) TOSFOS answers further that since the salt and water are essential to the making of the dough, they are considered to be the same type of food as the dough. Similarly, since the spices are indispensable to the taste of the food, they are considered to be the same type of food. (This means that the salt and water are viewed as a new, completed food item. The mixture is considered a "piece of dough" and not just flour, salt, and water mixed together.)
(c) The RAN in Nedarim (52a) gives a novel explanation for why a "Davar she'Yesh Lo Matirin" is not Batel in the case of a mixture of Min b'she'Eino Mino (see also Insights to Beitzah 4:1). His explanation answers why Rav Ashi applies the rule of "Davar she'Yesh Lo Matirin" in the case of the Gemara here.
The Ran explains that an item of Isur becomes Batel in a mixture with items of Heter because when opposites combine they contrast and annul each other (whichever one is the majority annuls the one which is the minority). This is the mechanism of the concept of Bitul. In contrast, when like items combine one cannot annul the other since there is no element of contrast.
Normally, when an Item of Isur becomes mixed with Heter, one annuls the other. Even though the two items are the same type of food (Min b'Mino), they contrast because one is Asur and one is Mutar. As such, they are considered opposites. However, if an item is Asur now and will become Mutar later, it cannot become Batel when it falls into Heter because there is not enough opposition; it is as if the item of Isur (which will become Mutar later) is Mutar right now. This is why the stringency of a "Davar she'Yesh Lo Matirin" exists only in a case of a mixture of Min b'Mino (two of the same types of food). In a case of a mixture of Min b'she'Eino Mino (two different types of foods), even if the Isur will become Mutar later, there is still enough opposition to be Mevatel it due to the different nature of the foods themselves. In a mixture of Min b'Mino, the only opposition is the fact that one item is Asur and the others are Mutar. (See also TESHUVOS HA'RAN #51.)
In the case of the Isur of Techumin, however, not only is the Isur a "Davar she'Yesh Lo Matirin," it is a "Davar ha'*Mutar*" itself. That is, the dough is permitted at the present moment on Yom Tov as long as one keeps it within the range of its Techum. (This is in contrast to a normal "Davar she'Yesh Lo Matirin" which is prohibited at the present moment and which becomes permitted only at a later time.) In the case of Techumin, the two objects in the mixture are "Heter b'Heter." In this case, the opposition between the two different types of food items is not enough to cause Bitul to occur. Even though the items are "Min b'she'Eino Mino," no Bitul will occur since the objects are both permitted.

39b----------------------------------------39b

2) THE "TECHUM" OF WATER TAKEN FROM A PUBLIC PIT ON BEHALF OF SOMEONE ELSE
OPINIONS: The Gemara says that water taken from a public pit on Yom Tov acquires the Techum of the person who takes the water. Rav Nachman and Rav Sheshes disagree in a case of one who draws water for his friend from the public pit. Rav Nachman says that the water he draws acquires the Techum of the one for whom it was drawn. Rav Sheshes says that the water acquires the Techum of the one who drew it from the pit.
The Gemara concludes that their dispute is based on whether an act of "Magbi'ah Metzi'ah l'Chaveiro" is effective. When one finds an ownerless object and lifts it up with intent to make an acquisition on behalf of his friend, does the object become the possession of his friend or not?
How does the question of "Magbi'ah Metzi'ah l'Chaveiro" affect which person's Techum the water drawn from the pit acquires?
(a) RASHI explains that both Rav Nachman and Rav Sheshes maintain that one who finds an object cannot acquire it on behalf of his friend; when he lifts up the object, his friend does not acquire it. (Indeed, Rav Nachman expresses this opinion explicitly in Bava Metzia 10a.) The question is whether the first person, the one who picks it up, acquires the object when he picks it up for his friend. Rav Nachman maintains that he does not acquire the object because he did not intend to acquire it for himself when he picked it up. Rav Sheshes says that since the second person does not acquire the object, the first person acquires it.
TOSFOS questions this explanation. What does Rav Sheshes mean when says that the first person acquires the object? He had no intention to acquire it for himself when he lifted it! (The Gemara in Bava Metzia (10a) teaches that a person's intent can prevent a Kinyan from taking place. For example, even though a person can acquire an object with a Kinyan of "Arba Amos" (when an object is within a person's four Amos, his four Amos can acquire the object for him), if he finds an object and falls on it with intent to acquire it in that manner (by falling on it), he does not acquire the object at all. The Kinyan of "Arba Amos" does not work because he did not intend to acquire it with his "Arba Amos," and falling on it does not work because that is not a valid act of Kinyan.)
Rashi may understand that the person who lifted the object knows that he is able to acquire it for himself and does not mind acquiring it for himself. The only reason he does not intend to acquire the object is because he thinks he can acquire it on behalf of his friend. Had he known that he cannot effect a Kinyan for his friend and that the object is still Hefker, he would have intended to acquire it for himself (so that nobody else could take it) and then he would have given it to his friend. Since he would have wanted to acquire it for himself had he known that he cannot acquire it directly for his friend, and since he did not have specific intention not to acquire it for himself, he therefore acquires it for himself. (In the case in Bava Metzia of the person who falls on an object with intent to acquire it in that manner, the person does not know that he can acquire the object from Hefker with "Arba Amos" in the first place, and thus he does not acquire it with "Arba Amos." Even if he knows that it is possible to acquire an object with the Kinyan of "Arba Amos," by falling on the object he demonstrates that he does not want that Kinyan to take effect.)
(b) TOSFOS cites the RASHBAM who explains the Gemara differently. Rav Sheshes maintains that when one lifts an object with intent to acquire it on behalf of his friend, his friend does not acquire the object ("Lo Kanah Chaveiro"), and that is why he says that the water obtains the Techum of the person who draws it from the pit. Rav Nachman, on the other hand, maintains that his friend does acquire the water at the moment the first person draws it from the pit, because he maintains that "ha'Magbi'ah Metzi'ah l'Chaveiro Kanah Chaveiro" -- when one who lifts an ownerless object for his friend, his friend does acquire it.
How can Tosfos say that Rav Nachman maintains "Kanah Chaveiro"? In Bava Metzia (10a), Rav Nachman himself rules "Lo Kanah Chaveiro"!
The Rashbam explains that the case of the Gemara here is an exception to Rav Nachman's rule. In the case of a single lost object, if one could acquire it for his friend no one else would be able to acquire it, and thus the Kinyan does not work. In the case of the Gemara here, there is enough water in the pit for others even after one draws water for his friend. By taking water for his friend he causes no loss to others, and therefore his friend acquires the water.
RABEINU CHANANEL in Bava Metzia (10a) and the RASHBA here similarly explain that Rav Nachman rules that the other person does acquire the water in this case, but not because this case is different. Rather, they explain that Rav Nachman retracted his ruling and now maintains that "ha'Magbi'ah Metzi'ah l'Chaveiro Kanah Chaveiro."
(c) RABEINU TAM says that Rav Nachman is consistent with his opinion that "ha'Magbi'ah Metzi'ah l'Chaveiro Lo Kanah Chaveiro." Why, then, does Rav Nachman say that the water obtains the Techum of the person for whom it was drawn? Rav Nachman means that when it comes into the hands of the second person, he acquires it and, in turn, it acquires his Techum because the first person never intended to acquire it for himself.
Rav Sheshes, on the other hand, maintains that "ha'Magbi'ah Metzi'ah l'Chaveiro Kanah Chaveiro." Why, then, does he maintain that the water has the Techum of the person who drew it from the pit? Rav Sheshes maintains that the reason why one can acquire something on behalf of his friend is because of the logical principle of "Migu d'Zachi l'Nafshei" -- since he could have acquired the item for himself, he is able to acquire it for his friend. Since his ability to acquire the object for his friend stems from his ability to acquire it for himself, the object acquires his Techum even though it belongs to his friend.

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