Reference for Bava Batra 118:6

ואידך אמר ליה זימנין דבעיתת:

Rab Judah, however, said that the owner of the courtyard cannot prevent the owner of the roof either. May we say that the point at issue between them is whether overlooking [constitutes a genuine damage], one holding that it does, and the other that it does not?<span class="x" onmousemove="('comment',' The owner of the courtyard can be 'overlooked' from the spar by the owner of the roof, but not vice versa. ');">⁵</span>

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