Bava Metzia 2 - 8
“It is assumed that whatever is in one’s possession is his.”
Similar to the well-know adage that “possession is nine-tenths of the law”, Tosefot cites this logical reasoning 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.
In our mishna we are taught that two people who are holding a garment and each person claims that he bought the entire garment, or found the garment first, they divide the garment equally after making an oath of Rabbinical origin. However, in Bava Batra a case of two people claiming ownership of a boat is discussed, and the law in that case is “kol d’alim gavar” (literally “whoever is stronger wins”, which is explained in various manners by the Rishonim in that sugya) — but not that the court rules that they divide the boat equally. What’s the difference between this 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 the boat — they divide it equally.
- Bava Metzia 2a