Bava Metzia, chapter 8, Mishnah 4. We have moved on from the laws relating to guarding and watchmen, but we are still in the broader topic of monetary laws, which will accompany us into the next chapter. The Mishnah before us deals with a matter very similar to what we saw a few mishnayos ago: two parties - here a buyer and a seller - who disagree about who is entitled to what, and claims of certainty and uncertainty.
The first case - uncertainty regarding the time of birth:
The first case deals with a person who buys a cow that was pregnant at the time, and it is unknown whether she gave birth before the acquisition was made or afterward. Therefore, it is unclear who is the legal owner of the newborn calf.
First, we must clarify the scope of the dispute. Let us assume that a cow - large or small - is worth 100, and a pregnant cow is worth 150, since it holds the potential to give birth to a calf. The transaction was certainly made for a pregnant cow, meaning a transaction of 150, and the dispute revolves around the remaining 50:
The calf was born after the transaction - the buyer is entitled to two animals, worth 200.
The calf was born before the transaction - it belongs to the original owner, and the buyer only received a cow for his 150, and therefore is owed another pregnant cow or the value of the additional 50.
To establish such a doubt, we must find a transaction where the act of acquisition takes effect even though the cow is not in front of us. This is complicated, because with movable property - including an animal - physical possession is required: lifting, pulling, or handing over, and every animal has its appropriate method of acquisition. A cow must be pulled and led, and if so, the buyer would see with his own eyes whether she had already given birth.
Acquisition by exchange:
The method the Mishnah uses is acquisition by exchange, meaning a swap. One has a cow and the other a donkey, and they wish to exchange them. Once one of the parties makes an acquisition on the other's animal - pulling the donkey and acquiring it - the cow immediately transfers to the ownership of the one who previously owned the donkey, wherever it is in the world. And since the cow is standing on a distant farm, the question can arise as to whether she gave birth before the acquisition was performed or afterward. This is the background to the Mishnah.
The Mishnah states: "Hamachalif parah bachamor veyaldah" - an exchange transaction was made between a cow and a donkey, and the cow gave birth, and we do not know if the birth was before the acquisition of the donkey or afterward. "Vechen hamocher shifchato veyaldah" - the exact same law. A maidservant can also be acquired with money, whereas other movable property is not acquired with money, since slaves are compared to land. Therefore, the same situation is possible: the buyer gives money for the maidservant while she is in a distant location, and it is unknown whether she gave birth before the money was taken or afterward.
"Zeh omer ad shelo macharti vezeh omer mishelakachti" - the seller claims that the offspring was born prior to the sale and therefore it is his, and the buyer claims that it was born after he bought the cow through pulling the donkey and therefore it is his. The argument is over the additional value, and the same applies to the offspring of the maidservant.
The Mishnah instructs "yachaloku" - the parties divide the disputed value between a pregnant cow and a cow and calf, meaning 50: one of them gets the calf and returns 25 to his fellow. This law follows the view of Sumchos, that money cast in doubt is divided - when it is unknown to whom the money belongs, they divide it half and half.
However, the halachah does not follow Sumchos, but rather the Sages: the burden of proof rests on the one seeking to extract property from his fellow, and a person cannot extract money without proof. Since neither party has proof, the calf remains in the hands of the one in possession, and he is the original owner.
The Second Case - The Large or Small Field:
The Mishnah continues with someone who had two slaves, one large and one small, or two fields, one large and one small - naturally, one is worth more and the other is worth less. A transaction took place, the seller took his hundred shekels, and now the parties are in dispute.
"Halokach omer gadol lakachti, vehamocher omer eini yodea" - The buyer says, "I bought the large one," and the seller says, "I do not know":
The buyer claims: I am entitled to the large field or slave; and the seller replies that he does not remember and is not sure that this was the case. We have before us a case of certainty versus uncertainty: one is certain in his claim and the other is unsure. The Mishnah rules that the buyer wins the large field or the large slave, which seemingly implies that certainty is preferred - the one who claims with certainty is the winner. However, as we learned earlier, the halachah is not so: it is not enough for a person to be certain that the item is his in order to win it, even when his fellow is unsure.
Therefore, the case in the Mishnah is that the parties are not disputing a specific plot of land, but rather the value. The buyer says: What I gave you was worth a large field; and the seller replies: I am not sure, perhaps it was not worth a large field. Consequently, the seller admits to part of the claim and denies part of it, and is therefore obligated to swear an oath. However, he does not know whether he agreed to the large field or not, and he cannot swear an oath regarding the additional value. And the rule is: since he cannot swear, he pays. Because of this, the buyer wins the large field, for the one who admits to part of the claim cannot exempt himself with an oath.
"Hamocher omer katan macharti, vehalokach omer eini yodea" - The seller says, "I sold the small one," and the buyer says, "I do not know":
Here the ruling is "Ein lo ela katan" - he receives only the small one - the buyer gets only the small one, and the seller is not required to do anything, not even to swear an oath. For the seller stands by his claim with certainty that he only owes the small one, and there is no claim against him at all. There is no partial admission here, and there is no oath of partial admission against an uncertain claim.
"Zeh omer gadol vezeh omer katan" - This one says the large one, and this one says the small one:
Both parties make certain claims: this one insists that he is entitled to the large one, and this one insists that he sold the small one. The ruling is "Yishava hamocher shekatan machar" - the seller must swear that he sold the small one. From the perspective of the burden of proof being on the claimant, the seller cannot be obligated to give the large one. However, since he partially admits to the claim, he is obligated to swear an oath - and here he is able to swear, since he is certain of his claim. He swears about the value of the difference, gives the small one, and with that the judgment concludes.
Note: What is the dispute about?
A side point, important but technical: the claim over which they are disputing cannot be about a specific plot of land or a specific slave, since then there is no oath, for several reasons. First, there is no oath of partial admission for real estate and slaves, as we learn from other sources. Second, there is an additional rule: one who claims from his fellow, "You owe me wheat," and the other replies, "I owe you barley" - the wheat is worth 100 and the barley 80 - this is not a partial admission, but a complete denial of the wheat claim and a separate admission to the barley debt, and this does not create an obligation for an oath of partial admission.
Therefore, the case must be that the claimant argues, "You owe me barley worth ten," and the defendant replies, "It is only nine," or that the claimant demands a high value for a field or a slave and the defendant replies that the value is lower. Since the dispute is centered on the value of the debt, there is a partial admission and a partial denial here - and this is a partial admission that obligates an oath.
"Zeh omer eini yodea vezeh omer eini yodea" - This one says, "I do not know," and that one says, "I do not know":
The final case is where both parties, the buyer and the seller, do not remember whether they were discussing the large one or the small one. In this case, the Mishnah states, "yachaloku" - they divide it. Once again, this follows the view of Sumchos: money whose ownership is in doubt is divided - since it is unknown who is entitled to what, they split the difference.
Once again, this is not the halachah. The halachah follows the Sages: the burden of proof rests on the one seeking to extract property from his fellow. This means that the large field remains in the possession of the current holder and the small one goes to the buyer, since he has no proof to the contrary. There is not even an oath here, because without a definite claim that the buyer is owed more, the seller is not required to swear as one who partially admits. It is very simple: he keeps the large field or slave for himself, and gives the small one to the buyer.