Bava Metzia 2-8
Possession and the Law
“It is assumed that whatever is in one’s possession is his.”
Similar to the well-known adage that “possession is nine-tenths of the law”, Tosefot cites this logical concept of possession to explain the distinction between the law taught in the first mishna of Bava Metzia and the law taught in an apparently identical case in Bava Batra 34b.
Our mishna teaches about two people who are holding a garment, with each person claiming that he bought the entire garment or found the garment first. The law is that they divide the garment, but both need to take an oath of Rabbinical origin that was enacted to stop people from grabbing the property of others. However, in Bava Batra, a case where two people claim ownership of a boat is discussed, and the law in that case is kol d’alim gavar (literally “whoever is stronger wins,” with the exact meaning and reasoning being explained by the Rishonim).
However, the ruling is not that the court says that they divide the boat equally. So, what’s the difference between the boat case and the case when they both hold a garment? Tosefot explains that when the claimers are in possession of the disputed item, it is different, since “It is assumed that whatever is in one’s possession is his.” Being that they both are holding the garment and are both in possession of it, unlike in the case of the boat, they divide it equally.
Bava Metzia 2a