Gemara Clarity

Niddah 23a

נדה כ״ג ע״א

Learn Niddah 23a step by step: Aramaic beside English, every question, answer and proof colour-coded.

Open Niddah 23a in Gemara Clarity

Topic

How strong a גזירה שוה is depending on its free words, and the reasons behind רבי מאיר's view on animal-shaped miscarriages

Overview

The amud opens by finishing a point about גזירה שוה: a comparison whose words are מופנה (extra) on both sides beats one that is מופנה on only one side. רב אחא בריה דרבא then gives a more lenient version of רבי אלעזר's rule, and the גמרא explains what difference it makes for רבנן. It also shows the logical refutation that knocks down the comparison between a person and a sea monster. Next the גמרא looks for the reason behind רבי מאיר's view that a woman who miscarries an animal-shaped fetus is טמאה לידה. It offers several reasons: the word יצירה, eyes like a person's, and eyes that face forward. Each reason is challenged and defended. אביי says רבי מאיר's bird case means only owls, and the גמרא works through two ברייתות about birds. Finally, רבי ירמיה asks a joking question about betrothing such a creature, and the גמרא returns to רב's statement that רבי מאיר counted it only because its kind can live. רב ירמיה מדפתי's comment on that statement continues on the next amud.

Opening lines

וְיָלְפִינַן מוּפְנָה מִשְּׁנֵי צְדָדִין.

And we derive from the analogy that is free on both sides.

וּלְהָכִי אַפְנְיֵהּ רַחֲמָנָא

And for this reason the Merciful One made it free

לִבְהֵמָה מִשְּׁנֵי צְדָדִין,

the analogy of animal, on both sides,

כִּי הֵיכִי דְּלָא נִגְמַר

so that we would not derive

The steps (32)

  1. ResolutionWhy the animal comparison is free on both sides
  2. StatementA lenient version of the rule about free words
  3. QuestionWhat is the difference for the Rabbis?
  4. ResponseThe difference shows up when two comparisons clash
  5. QuestionWhat refutation knocks down the man and sea monster comparison?
  6. ResponseA person can become impure while alive
  7. Statementרבי מאיר's reason: animals are 'formed' like a person
  8. ChallengeThen a mountain-shaped miscarriage should count too
  9. ResolutionA woman can't deliver a mountain, only a 'clod'
  10. ChallengeThen a shapeless 'רוח' miscarriage should count
  11. ResolutionA verse from נביאים cannot teach a law of the תורה
  12. StatementA new reason for רבי מאיר: the eyes look human
  13. ChallengeThen a snake-shaped miscarriage should also count
  14. ResolutionWhy the משנה chose animals and not a snake
  15. ChallengeA blemish law suggests animal eyes are not like human eyes
  16. ResolutionOne source refers to the pupil, the other to the eyeball in its socket
  17. Statementרבי ינאי: the animals' eyes face forward like a person's
  18. ChallengeBirds' eyes don't face forward, yet רבי מאיר says טמאה
  19. Resolutionאביי: רבי מאיר means only owls
  20. ChallengeA ברייתא: רבי מאיר is right for animals, the חכמים for birds
  21. ChallengeIf the birds are owls, why treat them differently from animals?
  22. ChallengeSo the ברייתא must mean other birds, and then רבי מאיר argues about them too
  23. ResolutionThe ברייתא is missing words: רבי מאיר only argued about owls
  24. ProofA ברייתא says bird shapes must be checked
  25. ProofChecking only makes sense for רבי מאיר, who splits owls from other birds
  26. RejectionThe checking could follow the חכמים instead
  27. ChallengeWhy would the חכמים count owls but not animals?
  28. ResolutionOwls have cheeks like a person
  29. QuestionCan a father marry off an animal-shaped baby girl?
  30. ChallengeSuch a creature cannot even live
  31. Conclusionרבי ירמיה was trying to make רבי זירא laugh
  32. StatementThe statement itself: רבי מאיר's reason is that its kind can live