Baba Basra 70b - Claiming for Orphans O'nes

In the gemara, R' Amram, if reuven gives shimon a watch to hold for him and receives a contract in return verifying that shimon has his watch - is shimon believed to say that he returned the watch even though reuven still has the contract (in a case of a loan the holder of the contract is always believed, but in the case of a pikadon the gemara has a question). R' Chisda says that shimon is believed to say that he returned the pikadon. But, the gemara clearly states that the entire discussion whether shimon is believed is only when he claims to have returned it which contradicts the shtar being held by reuven, but if shimon claims that an o'nes occurred to the item, all agree shimon is definitely believed.

Based on this Tosafos asks, why does the gemara assume that even when shimon would die, reuven can use the contract to collect from his children. Although, the claim that shimon would have used, that he returned the item, would not exempt his children from paying, but had shimon claimed that an o'nes occurred he would have been believed. Therefore, we should claim for the yesomim that perhaps on o'nes occurred to the item, to exempt them from paying? Tosafos answers that we never claim "o'nes" for yesomin, because it is not common. The Ri"f in Baba Metzia (perek hamikabel) holds that we do make the claim of o'nes for yesomim. According to the Ri"f, the question of tosafos returns, why don't we exempt the yesomim of shimon from paying reuven based on the claim of o'nes?

The Steipler (34) elaborates on this issue. His basic premise based on a shita mikubetzes on 5b is that one who is holding a contract is considered as if he is holding the actual money. The Shita uses this in the context where a person holding a contract wants to use a migu to take money away from someone else, we don't consider it a mi'gu l'hotzi, because the one holding the contract is not considered to be "motzi" from the other. Similarly, he suggests that one holding the contract may have a stronger claim on the money than the one holding the money, so that the holder of the money cannot use mi'gu to retain the money, because we view him as being "motzi" money from the ba'al ha'shtar. If we consider the orphans of Shimon to be motzi from reuven, since reuven has a contract, it makes sense that we would not claim o'nes for the yesomim to retain the money, because their retaining is in essence being "motzi" from the ba'al ha'shtar. Just as we don't allow mi'gu to be "motzi" money from someone, we also don't claim for yesomim to collect money, only to retain money. Since we view reuven, the ba'al ha'shtar as being muchzak, the yesomim are being motzi, therefore in this case we cannot claim o'nes for them.

Baba Basra 66a - Opinion of Rashbam by "She'uvin"

The gemara implies that the p'sul of drawn water in a mikva is only d'rabonon, but the Rashbam is not willing to accept that statement at face value because of the braisa in toras kohanim that learns from a pasuk that a mikvah must be created bi'dei shamayim, rather than being filled by buckets. Tosafos quotes the rashbam to hold that כולו שאוב is d'oraysa. Simply, that would imply that only when the entire 40 se'ah is of drawn water would the mikvah be invalid. But, in actuality the Rashbam has difficulty constructing a case where drawn water will not invalidate the mikvah m'doraysa. The case that the Rashbam describes where it will not be pasul m'doraysa is when the mikvah was already full with 40 se'ah of rain water (not drawn), then one adds drawn water. Clearly, the Rashbam holds that if the initial 40 se'ah is comprised of some drawn water, the mikvah will be pasul m'doraysa.

In my sefer on mikvaos, Mayim Rabim (pg. 40) I pointed out that the proof that Tosafos cites to the Rashbam (and Rabbeinu Tam), actually doesn't fit with the actual opinion of the rashbam. Tosafos proves from the opinion of R' Eliezer that we are more machmir for she'uvin when the mikvah is completely empty (amount is revi'is), than when the mikvah is partially full (amount to pasul is 3 lug). Tosafos assumes that the m'doraysa the mikva would be passul if 3 lug were placed prior to any other water, therefore we are machmir m'drabonon for a revi'is. But once the mikvah is partially full with rain water, it can no longer be ruined m'doraysa, so we are only machmir m'drabonon not to put in 3 lug. This approach assumes that the p'sul d'oraysa will only apply when the she'uvin come before any other water, which is actually not the opinion of the rashbam who holds that until it is full with 40 se'ah the she'uvin have the capacity to passul the mikvah.

Another chiddush of the Rashbam (mayim rabim pg. 43) is that he understands that a 40 se'ah mikvah cannot become passul by adding she'uvin because the she'uvin is batul in the mikvah water. This would imply that if you add more than 40 se'ah of she'uvin, it will indeed invalidate the mikvah (but according to the second answer of rashbam that kama kama batul, perhaps it will remain batul even after the majority is she'uvin). The Beis Yosef points out that all rishonim disagree and maintain as Tosafos writes in the name of Rabbeinu Tam that a full mikvah cannot be ruined even if all the she'uvin in the world is added to it.

Baba Basra 65a - Halacha like R' Nachman

The gemara tells us (kesubos 13a and Baba Metziah 110a) that the halacha follows R' Nachman b'dinei - meaning that we rule like r' nachman on monetary issues. Our gemara seems to elaborate somewhat on exactly why that is the case. But first we have to know which R' Nachman we are even speaking about. Rashi in Gittin 31b holds that R' Nachman Bar Yitzchok (talmid of Rava) is the stam r' nachman in shas who is the son in law of the Nasi (as the gemara implies in chulin 124a that stam r' nachman was the chasna d'bei ne'siah). However, Tosafos disagrees and hold that the stam r' nachman in shas who was the son in law of the nasi was an earlier R' nachman, who was R' nachman bar yacov, a talmid of Shmuel and friend of R' Sheishes. So, rashi and tosafos argue whether the halacha is like r' nachman refers to R' nachman bar yitzchok or R' nachman bar yacov, but either way he was the son in law of the Nasi.

Now, our gemara explains why the halacha is like R' nachman. R' Nachman asked R' Huna whether the halacha is like r' huna (who holds that a seller sells b'ayin ra'ah), or like himself (rav nachman). R' huna told r' nachman that the halacha is like the opinion of R' nachman - why?

דמקרביתו לבבא דריש גלותא דשכיחי דייני - Rashbam explains that since he was a son in law of the Nasi he was privelleged to always be around the reish galusa who had power that was accepted by the secular government, so he was present when many monetary halachos were being decided. Does this mean he understood halachos of Choshen Mishpat better than his collegues? Not necessarily. Tosafos in chulin 18b and sanhedrin 5a writes that although the chachamim in E.Y. are wiser than those in bavel, the authority on money matters was with the reish galusa in bavel. As Tosafos in sanhedrin puts it the Rosh Goleh in bavel was from "zecharim" and the Nassi in EY was from nekaivos. B'kitzur the reish galusa wasn't necessarily the greatest scholar of all, just that he had the most power. Why would this make the halacha conform with R' nachman?

The gemara at the end of baba metzia says that they asked "shibur malka" who rashi identifies as the king of persia, and the gemara in baba basra 10 says was a goy about a choshen mishpat question and he "paskened" like R' Shimon. Why would his opinion count?

Perhaps R' Nachman wasn't greater than others in knowing every s'mah and shach in choshen mishpat. But, he had the most exposure to monetary issues and therefore had a better understanding of the mindset that people had when making monetary transactions. Perhaps this is what the gemara means when we say that the halacha was like R' Nachman because he hung around the reish galusa. This would also be why shibur malka was consulted. His halachic opinion would not be worth much, but his understanding of people and their intent was more astute.

Baba Bara 63b - Buying the Right to Dig Tunnels

Rav Dimi says that when one sells a house and intends to sell with the house the right to build tunnels underneath plus the right to build up higher, he must specify in the sale that he is selling עומקא ורומא - implying that the seller is giving these rights over to the buyer. However, if Reuven would sell a house to Shimon without specifying that he is selling עומקא ורומא then the assumption is that Reuven retains the rights to dig tunnels under the house (so long as it won't damage Shimon), and also retains the rights to build something over the air space (so long as it doesn't extend down into Shimon's property).

It is obvious that whoever we consider the owner of the land underneath the house has rights to build tunnels so long as he doesn't damage the house. We don't allow the owner of the house to dig tunnels since the area under the house doesn't belong to him.

However, the mishna at the end of chezkas habatim (60a) quotes an argument between the Rabbonon and R' Yehuda whether or not someone has the right to dig tunnels under the public domain. The entire machlokes focuses solely on whether or not the tunnels dug underneath the reshus harabim are going to damage the reshus harabim. The Rabbonon allow him to dig the tunnels so long as the ground of reshus harabim is sturdy enough to support a passing wagon filled with rocks. R' Yehuda forbids it out of fear that in the future it may not be as sturdy thereby turn into an obstacle in the reshus harabim. My wife's grandfather, Rav Yitzchok Gefen, (in his sefer Dalyas Hakerem) raises a powerful question: Why is the gemara focusing on damage to reshus harabim? There is a more fundamental reason for not allowing someone to dig tunnels under reshus harabim and that is, he is not an owner. If I own a piece of property I don't have to come up with reasons why I don't want you to build, just the fact that it is mine and not yours allows me to prevent you from building. Just as Reuven cannot dig under Shimon's house unless he has retained ownership over the right to build, one may not dig under reshus harabim unless they somehow purchase the ground underneath, regardless of whether or not they will eventually cause damage?

I would like to suggest that we can derive from here a perspective on determining ownership over reshus harabim. Reshus Harabim isn't viewed as owned by someone else, rather it is viewed as owned by everyone. It is like a chatzer of partners where everyone is a partner. When I am a joint owner in a piece of property I can do whatever I would like, so long as it doesn't harm my partner (either because i own those rights, or because my partner would be mochel anything that doesn't effect him so that i will in turn be mochel anything that doesn't effect me). Similarly, one who owns a property adjacent to reshus harabim can dig underneath so long as his infinite number of partners will not be harmed by it. Therefore, the mishna doesn't focus at all on "ownership" because in the context of reshus harabim he isn't missing ba'alus. Rather it focuses on potential damage that the tunnels will cause because even an owner doesn't have rights to cause damage to his partners.

Baba Basra 60b - Decree to Abstain From Pru U'rvu

R' Yishmael Ben Elisha said that from the day that the Roman government started to make decrees against keeping Torah and mitzvos it would have been appropriate to make a decree taht everyone should abstain from having children (better we cease to exist rather than they destroy us through assimilation), but we can't impose a gezeira that most people cannot withstand.

This gemara is very difficult because it seems to go against the grain of our hashkafa. We should leave Hashem's business in his hands but we must carry on and fulfill our obligations. There are 4 approaches to this gemara:

1. Tosafos are troubled, how can we abolish the mitzvah of p'ru u'rvu? Tosafos answers that of course people would have still been performing the bare minimum of the mitzvah to have a son and daughter, but at that point they would abstain. The issue of זרעו של אברהם כלה is that klal yisroel won't grow because parents would replace themselves by having one son and one daughter.

2. The Chasam Sofer points out that the Mordechai in Yevamos understands this gemara as it sounds, that they would completely abstain from having children. The Mordechai (cited by Beis Shmuel siman 1) holds that nowadays we don't force a man to divorce his wife in order to fulfill his mitzvah of p'ru u'rvu since anyway there should have been a gezeira against having children. The Mordechai seems to hold that one way or the other klal yisroel would be lost. They would either be lost spiritually through bitul of torah and mitzvos leading to assimilation, or they would be lost physically through bitul p'ru u'rvi. It would be better that they end their existence on a high spiritual level, rather than a low.

3. However, the Chasam Sofer himself has a novel approach. It is impossible for the Jews to cease to exist because Hashem had promised to never destroy the Jews. The idea was that when they saw the goyim decreeing against Torah and Mitzvos and they watched the Jewish people dwindle spiritually, the plan was to decree against marriage so that divine intervention would be invoked sooner to save the existence of klal yisroel. The reason that they didn't do this is because there would be resha'im who would not pay attention to the gezeira and continue to have children, which would allow for the continuation of the Jews on at least a minimal level, thereby preventing divine intervention.

4. It is worthwhile to point out that the Meiri seems to have a different version of the gemara. According to our version which ends with the statement - מוטב שיהיו שוגגין ואל יהיו מזידין, the implication is that if the gezeira would be followed, then it would be ideal to implement it. However, the Meiri ends by quoting the statement that Yeshaya told Chizkiya in Brachos - בהדי כבשי דרחמנא למה לך. Meaning, Hashem will deal with his business but we must do whatever we are obligated and able to do. Therefore, the conclusion of the gemara is that the suggestion is ideologically flawed, not just impossible to practically implement.

Baba Basra 58a - Tumah on Mi'aras HaMachpeila

In the story with R' Bena'ah who marked off graves to make people aware of tu'mah, we find that it was necessary to even mark the graves of Avrohom and Adam, implying that they were me'tamei. Tosafos assumes that the only concern was tu'mah ohel but there wasn't any concern about physical contact with tu'mah. Therefore, Tosafos asks, Why should the graves of Avrohom and Adam be tamei? First of all, we follow R' Shimon in Yevamos 61a who says that goyim aren't metamei b'ohel because they are not called "adam" and therefore aren't included in the pasuk of אדם כי ימות באוהל. And even those who follow the Rabbonon, we have a rule in Nazir 54a that any deceased prior to the giving of the Torah isn't meta'mei b'ohel? Tosafos is forced to say that R' Bena'ah held that they are exceptions to the rule because the Torah explicitly refers to Avrohom and Adam as "adam". Therefore, they are included in the pasuk of אדם כי ימות באוהל. It seems from Tosafos that even R' Shimon who holds that goyim aren't metamei b'ohel would agree that they are exceptions to the rule since the torah explicitly refers to them as "adam".

The Ran (chiddushim) is bothered by the same question. However, the Ran assumes that even physical contact with the tu'mah could have been a concern (presumably, this is only a concern by people such as the Avos who would not have decomposed, but otherwise a bone less than the size of a barley kernel is not me'tamei). Therefore, the Ran is only troubled within those who hold that a kohen is even allowed to come into physical contact with the grave of a non-jew (assuming we paken like R' Shimon). The Ran answers (as does the Ramban) - מפני כבודן ציין דכיון דקבילו עלייהו תורה ומצות הרי הן כישראל. It seems from the answer of the Ran that tu'mah is associated with the kedusha of mitzvos. Only those who are included in mitzvos, have the void that creates tu'mah upon their death. Therefore, people who were careful to keep Torah even prior to the receiving of the Torah, have the kedusha of klal yisroel, so that when they die they are me'tamei b'ohel. This will explain why Avrohom and even his descendant (who the Ramban in chumash assumes also kept the torah) were me'tamei b'ohel. It would also imply that Adam kept the Torah as well, which is something that we don't find a source for.

Whether we follow Tosafos or the Ran, a kohen should not be allowed to enter me'aras ha'machpeila. But, regarding kever rachel, it seems that Tosafos and the Ran would disagree whether or not we allow a kohen to enter.

Baba Bara 55b - Sfeik Sfeika by Tu'mah

Tosafos cites 3 different approaches to explain the machlokes between the Rabbonon and R' Elazar:

1. Rashbam - All agree that a safeik tu'mach in reshus hayachid is ta'mei. All agree that sfeik sfeika is tahor. The machlokes is whether the safeik of coming into the field that contains the tu'mah and the safeik of whether he came into contact with the tu'mah qualifies as one safeik, or as a sfeik sfeika. R' Eliezer considers it sfeik sfeika, whereas the Rabbonon consider it one safeik. The reason that the Rabbonon consider it only one safeik, the Rashbam writes - דסוף סוף מה לי שדה אחת מה לי ב' שדות, חדא ספקא היא וכו' וספקו טמא. The Rashbam seems to understand that the reason it is considered one safeik is like the "שם אונס חד הוא" logic that Tosafos uses in kesubos 9a - since it boils down to only one issue and that is whether there was contact with tu'mah we consider it only one safeik.

2. Rabbeinu Tam - The machlokes is whether the chiddush that safeik tu'mah in reshus hayachid is ta'mei, which we learn from sotah, applies even to a sfeik sfeika. Rabbonon hold that since it is a chiddush to be metamei in reshus hayachid, we are even me'tamei a sfeik sfeika. R' Elazar holds אין לך אלא חידושו and we are only metamei one safeik, but a sfeik sfeika would be tahor.

3. Rashi in Avodah Zarah 70a - The case is when there is only one safeik, there is no sfeik sfeika because the entire field is filled with tu'mah. If it were a sfeik sfeika then all would agree to be me'taher, but being that it is only one safeik there is a machlokes. R' Elazar holds that since the type of safeik we are speaking about is not a safeik of touching but a more removed idea of whether he even walked into the field, this is not the type of safeik that we are me'tamei in reshus hayachid, so we are me'taher. Rabbonon argue and hold that we are even me'tamei a ספק ביאה not just a ספק מגע.

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The Shach (y.d. 110 kuntres ha'sfeikos 14) discusses whether a sfeik sfeika must be מתהפך, meaning it may only qualify as a sfeik sfeika if it could be said in both directions starting from either safeik. But if it can only be said in one direction it wouldn't qualify as a sfeik sfeika. The Beis Meir (printed in margin of standard shulchan aruch) quotes our Tosafos to support a dissenting opinion that sfeik sfeika need not be מתהפך. From all the opinions in Tosafos it seems that we consider safeik bi'ah, safeik ma'gah, to be a sfeik sfeika. The sfeik sfeika will only work in one direction, but if we were to start with the safeik ma'gah, because once we say אם תמצא לומר נגע we no longer have any tzad to be metaher. Rashbam considers the point of argument to be whether this qualifies as a sfeik sfeika due to שם אונס חד הוא, but doesn't seem concerned with the fact that it is not מתהפך. Rashi has to make the entire field filled with tu'mah because all would agree that he is tahor relying on sfeik sfeika. Rabbeinu Tam also understands that it is a valid sfeik sfeika, the only issue is whether sfeik sfeika is tahor in a reshus hayachid, but in other contexts it would be a valid sfeik sfeika.

Baba Basra 54b - Dina D'malchusa between Jews

It is clear from the gemara that the concept of dina d'malchusa applies between a Jew and a gentile, so that even when the issue will ultimately boil down to a conflict between two Jews, we would still follow the dina d'malchusa since the issue began with a Jew and a gentile. In our gemara Reuven purchased property from a gentile and after paying but before receiving a contract Shimon made a kinyan in the property. Following dinei yisroel the property belongs to Shimon, but following dina d'malchusa it would belong to Reuven. The goy is essentially out of the picture because he got his money and has no more claim on the land, and the argument is only between Reuven and Shimon. Nonetheless, the gemara holds that we would follow dina d'malchusa to say that the goy did not relinquish rights to the property upon the receiving of money so that Shimon's chazaka was invalid, therefore the property belongs to Reuven.

The Chazon Ish (C.M. likutim 15) points out that from our gemara we see that if the issue begins between a jew and a gentile, even though it is 'megalgel' into a conflict between 2 jews, we follow dina d'malchusa. He also writes that the reverse is true as well. If the issue begins between 2 jews, then they are bound by dinei yisroel even if they are living in a secular country that has other laws. But this is only true if the government doesn't care that the Jews are following a different system. So long as the government is not makpid that the Jews follow their system such as in monetary issues where the side that would win in secular law but not in Jewish law can always be mochel their claim, all conflicts between Jews must be judged according to Torah law. The Chazon Ish is medayek this from the R"I cited by the Shita mikubetzes (baba basra 55b) that even if the secular courts require 40 years for chazaka, they are not makpid about Jews following a 3 year chazaka system since the מערער can be מוחל on his claims, therefore they are obligated to follow dinei yisroel. However, if they would violate this din by going to secular courts and it would be judged by the secular courts it would be binding, since they used the power of the government to take it away from the machzik and give it to the me'ar'er.

Based on this, if for whatever reason the government was makpid that the Jews follow the secular system rather than the Jewish system in a particular monetary law, the dina d'malchusa would seem to trump the din torah (since the malchus has the ability to take away money from the person who was zocheh in din torah and give it to the other). The Chazon Ish (#3) writes this explicity: In a case where the courts charge a tax for contracts and are therefore makpid that contracts be done in secular courts, even contracts between 2 Jews are bound to dina d'malchusa since we consider it like an issue between a jew and a goy (the goy being the government who wants to charge the tax).

Baba Basra 54a - Role of Intent in Kinyan

The gemara makes a distinction between one who prunes a tree, whether or not he intends to improve the tree or just collect the wood. The litmus test to determine what exactly he is doing is that if he prunes evenly on both sides he is clearly trying to improve the tree and is therefore a chazaka, but he only prunes on one side he is merely trying to pull out as much benefit from the tree as he can.

Why does the gemara use the term "אדעתא דדיקלא" and "אדעתא דחיותא", which implies that we are dealing with a kavana issue. Regardless of his intent, he is only doing an action of chazaka if he improves the field! From this the Rishonim all seem to understand that even if he doesn't prune the tree evenly, he is nonetheless causing an improvement to the field (Tosafos - ואע"פ שמתקן הקרקע). So what is the distinction between pruning evenly vs. pruning unevenly?

Tosafos understands that the issue in the gemara is whether the machzik intends to make a kinyan to acquire the property. If he prunes evenly we assume he is trying to make a kinyan, but if not then we assume that he is not trying to make a kinyan at all.

However, the Rashbam seems to understand that even when he prunes unevenly, we are confident that he is intending to acquire the field - ומיהו בלקיטת הענפים מתכוין הוא להחזיק בדקל ולקנותו בחזקה זו. The Rashbam holds that aside from intent to acquire the property, he must also have intent to improve the property. One can only make a kinyan on a property if he: 1. intends to acquire. 2. improves the property. 3. intends to improve the property. The test of whether he prunes evenly or not is really a test to determine whether he is doing this act of pruning with the intent of improving the property.

There seems to be a fundamental argument between Tosafos and the Rashbam whether it is sufficient to have intent to acquire (tosafos) or whether one must intend to improve the property in order to acquire it (rashbam). What is the machlokes? It seems that they argue whether chazaka is just a ma'aseh kinyan or an expression of ownership. Tosafos holds that if one intends to be ko'neh through this ma'aseh kinyan, he is ko'neh, but he doesn't need to intend to improve the property. So long as he is doing an action of improving the property it qualifies as a ma'aseh kinyan, therefore when he intends to acquire through this ma'aseh kinyan he is ko'neh. But, the Rashbam seems to understand that chazaka is not just a ma'aseh kinyan. The Rashbam holds that chazaka is a method of the new person expressing his ownership through this action. The expression of ownership is not a ma'aseh kinyan, rather since he is acting like an owner of the field we now treat him as an owner. Being that the chazaka is really just a means of the new owner expressing his ownership, he must have intend to improve the property as an owner would with the intent to acquire. It is only through the intent to improve the property that he is showing his ownership of the property.

Now, even according to the Rashbam who maintains that the purpose of pruning evenly is to demonstrate that his intent is to improve the property, it is possible that if we had witnesses who can testify that his intent was to improve the property in order to acquire it, even if he only pruned one side of the tree he would succeed in his acquisition. However, the Rosh (63) holds that the purpose of pruning evenly is not to demonstrate his intent. The Rosh writes - כללא דמילתא צריך שיעשה מעשה הנראה לעינים שעושה לתקן הקרקע הלכך שקיל רברבי ושביק זוטרי אע"פ שהקרקע מתקנת בכך וגם הוא אומר שכוון לתקן וכו' אפילו הוא אומר שעשה לתקן וכוון לקנות לא מהני

Meaning, it is insufficient for him to intend to improve the property in order to acquire. He must do an action that is clearly recognized by all as an action that is being done in order to improve the property. The Rosh holds that chazaka must be more than a demonstration of ownership from the perspective of the person making the chazaka. It must be an act that is objectively recognized by outsiders as a demonstration of ownership.

Baba Basra 53b - Kinyan by Spreading out Mats

The gemara says that one can make a kinyan on a parcel of property by spreading mats out on the property and continues to prove this point from the fact that one can make a kinyan on an eved by working with the eved. There seem to be (at least) 3 approaches as to why this works:

1. Rashbam explains that although one is not making any improvements in the property which is the more typical type of chazakah, he is enjoying and benefiting from the property by the service that he is receiving from the property. Based on this approach the Rashbam demands that he actually recline on the mats. It would seem that according to the Rashbam, the spreading of the mats is not so significant, but rather the significance is that the property is serving him. This would lead one to assume that the consumption of the fruits would also qualify as a chezkas kinyan, so the rashbam 54a is forced to explain why this is more kinyan-like than consuming the fruits of the property - דהתם קמיתהני גופו מן הקרקע וקמשמא ליה קרקע כעבד לרב. The Rashbam holds that the kinyan is not merely achieved from receiving benefit from the property, rather the property must be serving him directly as a slave would serve a master. Based on this approach the Rashbam explains that the gemara only intends to compare the spreading of mats on the property to the slave lifting the master, because in both cases the thing that is being acquired is "holding" the owner and servicing him in the process.

2. Rabbeinu Yonah understands that and benefit that one receives from the property enables him to make a chazaka. Based on this more open approach, it seems that any service that the slave is doing for a master is comparable to the benefit of using the property for a physical pleasure.

3. Tosafos and the Rosh seem to understand that there must be a clear display of ownership which they refer to as a "chazaka chashuva". This is only achieved by the act of spreading the mats AND using the mats. If one were just to spread out mats or just to use the mats it is not a chazaka. Based on this, the Rosh adds that if one were to set a table on the property and eat from it, it would also be a chazaka.

4. Rambam (zechiya 2:4) seems to group the spreading of mats with the painting pictures, indicating that the chazaka is achieved because it is an improvement of the property. The magid mishneh brings to explanations of the Rambam (the two explanations are separated by the words "פעם אחת", which is clearly an editor mistaking the abbreviation of פירוש אחר). The second explanation of the magid mishna is that the chazaka is somewhat of a standard chazaka that comes from the improvements to the property. The lechem mishna explains that the proof from the braisa by acquiring a slave is that from the fact that the braisa makes the distinction of who does to whom only by lifting up, implies that by all the other things listed such as putting on shoes works even if the master does it for the eved, because it is an improvement being made in the eved. Although this resembles a very standard type of chazaka, the chiddush is that even though it is only temporary and somewhat external, such as laying down mats and putting on shoes, it is still considered an improvement to the actual property and therefore works as a chazaka.

Baba Basra 48b - Uprooting Kiddushin

The Gemara discusses a case where one is mekadesh a woman by force, until she consents to the marriage. Mar Bar Rav Ashi holds that although a sale of this type would be binding, by marriage it would not be, because chazal uproot such a marriage. The gemara goes through the whole routine that it does in many other places (hesubos, yevamos, gittin) and says that we understand the mechanics of how they can uproot the kiddushin if it were done with money, but if the kiddushin was achieved through bi'ah, then what. To which the gemara responds that the chachamim turn the bi'ah into a bi'as ze'nus.

Normally, when the gemara goes through this, it prefaces by saying - כל דמקדש אדעתא דרבנן מקדש. Here the gemara doesn't do that. The Rashbam explains that the gemara is relying on that here as well. Therefore, the q and a of the gemara focuses on implementing this ability to uproot the kiddushin. By kesef they have the ability to remove the kesef kiddushin by making it hefker thereby uprooting the kiddushin, but by bi'ah what can they do with the bi'ah. They can't uproot the act of bi'ah? The gemara responds that they can turn the bi'ah into bi'as zenus.

However, Tosafos holds that the gemara intentionally deletes the concept of כל דמקדש אדעתא דרבנן מקדש, because that only applies when the original kiddushin was done according to the standards of the rabbonon. It doesn't apply here where the entire marriage was forced. Rather, chazal are using the general power that they have to uproot torah principles so long as it is passive. Based on this approach there is no reason that this power should be more applicable to kesef, than to bi'ah. Therefore, Tosafos explains that the issue in the gemara is not whether they "can", rather whether they "would". By kesef they are not causing any aveira by uprooting the kesef kiddushin and making it hefker, but by bi'ah the gemara questions whether the rabbonon would actually do such a thing. Would they turn the bi'ah into an aveirah in order to uproot the kiddushin, to which the gemara ultimately says, yes they would.

Why is the gemara content with uprooting the original kesef kiddushin. Presumably they have had relations throughout the marriage, any by uprooting the kiddushin it would turn the bi'ah of the past # of years into a bi'as ze'nus. Why is the gemara not troubled about that, just as it is about the bi'as kiddushin? According to the Rashbam it makes sense. The gemara is only concerned about what power the rabbonon are using, but is not concerned with turning bi'ah into ze'nus. But, according to Tosafos, why is it תינח דקדיש בכספא - what about all the bi'ah that they had thinking that the marriage was actually binding (unless you say that they would realize immediately that the marriage wasn't binding - but the question can still be asked in the other cases such as kesubos and gittin where something that happens 25 years into the marriage can cause the chachamim to uproot the marriage from the start)? It seems that the gemara understood that chazal weren't concerned with doing something that would "cause" the bi'ah to be bi'as ze'nus, so long as they are not actively turning the bi'ah into bi'as ze'nus. The only concern of the gemara is whether the rabbonon would actively turn the bi'ah into a bi'as zenus, which only applies when the kiddushin was done through bi'ah.

Baba Basra 47b - Self Imposed O'nes vs. External O'nes

R' Huna says that if one is forced into selling something and receives money for it, the sale is binding. The gemara explains the rationale is that everyone who sells items that are dear to them only does so under pressure and financial difficulty, yet the sale is binding, so this type of force is no different. To that the gemara responds - ודלמא שאני אונסא דנפשיה מאונסא דאחריני, meaning that there is a difference between a self imposed o'nes and an external o'nes. When one is forced to do financial pressures, he is making a decision under the circumstances. Although he would prefer to never be in such a predicament, nevertheless he is making a conscious decision under the circumstances - this decision is regarded as ratzon. But if one is being coerced or forced by someone else, we don't consider his decision to be b'ratzon so it is possible that the sale isn't binding (which is the opinion of Rav Bibi, unlike R' Huna who holds that so long as he receives something in return, it is binding).

This concept if very important to distinguish between what we can call an internal o'nes and an external o'nes. This issue arises in two places, but the distinction is exactly the same.

1. The Rambam in yesodei hatorah (perek 5) holds that if one's life is being threatened unless he serves avoda zara he is obligated to forfeit his life. But if he doesn't do so, he is still considered an o'nes and not killed for serving avoda zarah. Yet, the Rambam writes (halacha 6) that if one is deathly ill and uses avoda zara means to heal himself, he is chayev whatever punishment is normally associated with the act that he committed. Why is it considered o'nes when he is forced by others, but not when he is ill? The Ohr Samei'ach makes the distinction that is hinted to in our gemara (but doesn't mention the gemara). Based on our gemara the distinction is clear. When someone else is threatening to kill him, the decision that he makes is not considered "ratzon", because he doesn't at all want to do what he is being forced to do. But when he is ill and uses avoda zara to save his life, he is deciding to benefit from avoda zara. Surely, he is faced with extenuating circumstances, but that doesn't change the fact that he is making a conscious decision and is therefore liable for it.

2. The Rama writes in Hilchos Brachos (204:8) that if one is being forced to eat non-kosher food, even though he is enjoying the taste he doesn't make a bracha since he is considered an o'nes. But the Shulchan Aruch writes in the very next halacha that one who eats non-kosher because they are ill and they need it for medicinal purposes, makes a bracha on the food. The Taz (12) struggles with this and elaborates about it (siman 196:1). But based on our gemara the distinction is simple. One who is being forced to eat non-kosher by someone else is not making a decision to eat non-kosher, and would not eat it if not for being forced at gun point. Therefore, we don't consider this eating b'raztzon, and it is not worthy of a bracha. But, one who is ill, although he has severe circumstances, he is making a decision to eat the non-kosher food under the circumstances (and being that his life is threatened it is permitted for him to eat it), so we consider this to be a decision made b'ratzon and worthy of a bracha.

Baba Basra 43a - Techilaso V'sofo B'kashrus

The gemara says that when a sefer torah is stolen from a city, the dayanim of that city may serve as judges to convict the thief so long as they would relinquish their portion in the sefer torah. However, the gemara concludes that by a sefer torah where they will anyway be benefiting from the reading, it is not sufficient to relinquish their ownership since they will still be considered biased (nogei'ah b'davar) because they are ultimately benefiting from the sefer being returned to the city.

Tosafos asks that the gemara holds that for items other than a sefer torah it would help to relinquish their ownership thereby removing their negi'os. Why don't we require techilaso v'sofo b'kashrus? Meaning, we should require the dayanim to be kasher not only at the time of the judgement but even at the time of the crim? Tosafos answers that the requirement of techilaso v'sofo b'kashrus only applies to a passul in the guf such as a relative, but doesn't apply to a monetary passul. Tosafos in Nida 50 makes a distinction between an eid where we have such a requirement, and a dayan where we don't have such a requirement.

The Ramban explained by the Nemukei Yosef has a very interesting approach to this question. When one testifies on a monetary issue, he is not testifying on the money, rather he is testifying for the OWNER of the money. While it is true that we require techilaso v'sofo b'kashrus, and therefore one who was a relative through marriage at the time he witnessed a crime cannot testify on that crime even if he has divorced since then and is no longer a relative. The rationale is that at the time one witnesses the crime he must be kasher for eidus. But with a monetary issue such as a communal item that is stolen he is considered kasher l'eidus for all those that he is not related to, and passul l'eidus for the share of all those he is related to including himself. Therefore, by removing himself from this money, he is no longer testifying for himself, rather he is testifying for others and for them he was kasher all along to serve as a witness.

The R"I Mi'gash answers that one who is passul as a nogeiah, is not considered an eid at all. He is not like a karov who is considered an eid passul, rather he is not in the parsha of eidus. Therefore when he removes himself and becomes a valid eid, he is considered techilaso b'kashrus since that is the first moment that he assumes a status as an eid. This seems to be an exact opposite sevara from Tosafos. Tosafos considers the negi'ah of money so mild that we don't apply the din of techilaso b'kashrus, whereas the R"I Mi'gash considers it so severe that we don't even consider him to be an eid (in truth, there is a lot of discussion as to why a nogei'ah is passul. He is only passul to testify l'zechuso, but kasher l'chovaso, so he is not like a regular passul who is passul for chov and zechus. Some say it is a din of karov eitzel atzmo, some say it is a chashash meshaker, and some say he is not an eid at all - the latter seems to be the opinion of the R"I mi'gash).