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Eruvin 85a

עירובין פ״ה ע״א

Learn Eruvin 85a step by step: Aramaic beside English, every question, answer and proof colour-coded.

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Topic

Whether one person can forbid another's use through the air (אוסר דרך אויר): finding sources for שמואל and for רב

Overview

The גמרא brings a ruling about a בור (cistern) four טפחים away from the walls of two courtyards. Each neighbor may draw water through his window after putting out a small זיז (ledge), and רב יהודה says even a reed is enough. אביי tells רב יוסף that this ruling follows שמואל, because רב holds that one person does not forbid another 'through the air.' The גמרא looks for a source for שמואל's view. A proof from a roof next to a רשות הרבים is pushed off using רב פפא's explanation, so the real proof is the cistern ruling itself: a ledge is needed only because, without one, each neighbor would forbid the other through the air. Then the גמרא looks for a source for רב's view. A proof from two balconies, one above the other, is pushed off because the upper balcony has easier access, like a doorway against throwing. Finally the גמרא brings רב's ruling about two houses with three ruins between them, where each house may use the ruin next to it by throwing. The ruling continues on the next amud.

Opening lines

בּוֹר שֶׁבֵּין שְׁתֵּי חֲצֵירוֹת,

A cistern that is between two courtyards,

מוּפְלֶגֶת מִכּוֹתֶל זֶה אַרְבָּעָה

set four handbreadths away from this wall

וּמִכּוֹתֶל זֶה אַרְבָּעָה —

and four handbreadths away from that wall —

זֶה מוֹצִיא זִיז כׇּל שֶׁהוּא וּמְמַלֵּא,

this one puts out a ledge of any size and draws water,

The steps (11)

  1. StatementA cistern between two courtyards: each side puts out a small ledge and draws water
  2. Statementרב יהודה's own view: even a reed is enough
  3. Statementאביי: this ruling follows שמואל, not רב
  4. QuestionWhere do we know שמואל's view from?
  5. ProofFirst proposed source: a roof next to the public domain
  6. RejectionRejected: the roof case can be explained like רב פפא
  7. ResponseThe real source: the cistern ruling itself
  8. QuestionWhat is the source for רב's view?
  9. ProofFirst proof: the two balconies over the water
  10. RejectionPushing off the balcony proof: the upper one has easier access
  11. ProofSecond proof begins: two houses with three ruins between them