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Theorem frege62b 41515
Description: A kind of Aristotelian inference. This judgement replaces the mode of inference barbara 2664 when the minor premise has a particular context. Proposition 62 of [Frege1879] p. 52. (Contributed by RP, 24-Dec-2019.) (Proof modification is discouraged.)
Assertion
Ref Expression
frege62b ([𝑦 / 𝑥]𝜑 → (∀𝑥(𝜑𝜓) → [𝑦 / 𝑥]𝜓))

Proof of Theorem frege62b
StepHypRef Expression
1 frege58bcor 41511 . 2 (∀𝑥(𝜑𝜓) → ([𝑦 / 𝑥]𝜑 → [𝑦 / 𝑥]𝜓))
2 ax-frege8 41417 . 2 ((∀𝑥(𝜑𝜓) → ([𝑦 / 𝑥]𝜑 → [𝑦 / 𝑥]𝜓)) → ([𝑦 / 𝑥]𝜑 → (∀𝑥(𝜑𝜓) → [𝑦 / 𝑥]𝜓)))
31, 2ax-mp 5 1 ([𝑦 / 𝑥]𝜑 → (∀𝑥(𝜑𝜓) → [𝑦 / 𝑥]𝜓))
Colors of variables: wff setvar class
Syntax hints:  wi 4  wal 1537  [wsb 2067
This theorem was proved from axioms:  ax-mp 5  ax-1 6  ax-2 7  ax-3 8  ax-gen 1798  ax-4 1812  ax-5 1913  ax-6 1971  ax-7 2011  ax-10 2137  ax-12 2171  ax-frege8 41417  ax-frege58b 41509
This theorem depends on definitions:  df-bi 206  df-an 397  df-or 845  df-ex 1783  df-nf 1787  df-sb 2068
This theorem is referenced by:  frege63b  41516  frege64b  41517
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