Bava Metzia, Chapter 10, Mishnah 6. This is the last mishnah of the tractate, and it does not have a particularly dramatic conclusion. The reason for this is simple: originally, Tractate Nezikin was a single tractate of thirty chapters, and it was later divided into three sub-tractates - Bava Kamma (The First Gate), Bava Metzia (The Middle Gate, which is our tractate), and Bava Basra (The Last Gate), with ten chapters in each. We thus find ourselves in the middle of a topic: the laws of neighbors discussed here will continue to be explained in the first two chapters of Tractate Bava Basra.
The Case in the Mishnah:
The mishnah deals with "shtei ginos zo al gav zo" - two gardens adjacent to one another, one high and one low, with a wall or slope between them separating the upper one from the lower one. That is, if the owner of the upper garden were to step past the edge of his garden, he would fall into the lower one's garden.
And what is the halachah when "vehayarak beinasayim" - a vegetable is growing out of the wall between them? The roots of the vegetable are embedded in the ground belonging to the owner of the upper garden, while the fruit itself (a tomato or the like) is hanging in the airspace of the lower garden. They both make claims against each other as to who owns the fruit.
The Dispute Between Rabbi Meir and Rabbi Yehudah:
"Rabbi Meir omer, shel elyon" - the fruit belongs to the owner of the upper garden, since it drew its sustenance from his soil and land, and his resources are what made it grow.
"Rabbi Yehudah omer, shel tachton" - the hanging fruit is located in the airspace of the lower garden, and this airspace is his property, and therefore what grows in it is his.
Each of them brings a logical reasoning for his statement:
"Amar Rabbi Meir: im yirtzeh ha'elyon likach es afaro, ein kan yarak" - the vegetable depends on the soil of the upper one, and if he were to take his dirt from there, the vegetable would not exist at all. This shows that he controls it, and it comes into being through his power.
"Im yirtzeh tachton lemaleis es ginaso, ein kan yarak" - Rabbi Yehudah replies: The lower one can also fill his garden with dirt, since it is his garden and his airspace, and he would thereby cover and occupy the space where the fruit grows, and there would be no vegetable here. Thus, both of them alike can nullify the existence of the vegetable.
From here Rabbi Meir replies: "Me'achar sheshneihem yecholin limchos zeh al zeh" - since both of them have the ability to nullify the other, whether by removing dirt or by adding it, this claim cannot be a deciding factor, as they are equal in their power. Therefore, "ro'in me'ayin yarak chai" - we examine from where the vegetable draws its sustenance, and since it drew from the soil of the upper one, it is his.
The mishnah does not bring Rabbi Yehudah's answer, but it makes sense that he fundamentally rejects this reasoning: since the fruit grows in the airspace of the lower one, it belongs to the lower one. Thus, the dispute stands.
The Opinion of Rabbi Shimon:
A third approach is the opinion of Rabbi Shimon: "Kol sheha'elyon yachol lifshot es yado velitol, harei hu shelo, vehashar shel tachton" - any vegetable that the owner of the upper garden can reach out his hand and take is his; and whatever is too far away for him to reach belongs to the owner of the lower garden.
At first glance, it is difficult to understand the logic behind this distinction, and what the distance of the fruit or the length of a person's arm has to do with anything. However, Rabbi Shimon fundamentally agrees with Rabbi Meir: the vegetable grew from the upper owner's soil and belongs to him. But when the upper owner cannot reach the fruit, what will he do? He would have to go down from his garden to his lower neighbor and ask permission to cross through his garden just to pick a single tomato hanging on the wall. A person is embarrassed to do this and will not do it, as he is not willing to appear so petty for the sake of a single piece of fruit.
Therefore, Rabbi Shimon says: Since he will not bother to do this, he effectively declares the fruit ownerless and gives up on it, and as a result, the owner of the lower garden acquires it. The halachah is decided according to Rabbi Shimon: the fruit that the upper owner cannot reach is considered ownerless, and the lower owner acquires it.
In summary: In this Mishnah, we learned the law regarding a vegetable growing on a wall between two gardens, one above the other - its roots are in the upper soil and its fruit is in the lower airspace. Rabbi Meir awards it to the upper owner because the vegetable draws its sustenance from him; Rabbi Yehudah awards it to the lower owner because the fruit grows in his airspace; and since both can protest against each other, Rabbi Meir decides the matter based on the source of sustenance. Rabbi Shimon distinguishes between what the upper owner can take by reaching out his hand, which is his, and what is far from him, which the upper owner abandons out of embarrassment, and the lower owner acquires - and the halachah is decided accordingly.
And this is the end of Tractate Bava Metzia. Tractate Bava Metzia is completed, and from here we will continue to Tractate Bava Basra, where we will continue to learn the laws of neighbors, with God's help.