ILE Home Intuitionistic Logic Explorer < Previous   Next >
Nearby theorems
Mirrors  >  Home  >  ILE Home  >  Th. List  >  abbid GIF version

Theorem abbid 2283
Description: Equivalent wff's yield equal class abstractions (deduction form). (Contributed by NM, 5-Aug-1993.) (Revised by Mario Carneiro, 7-Oct-2016.)
Hypotheses
Ref Expression
abbid.1 𝑥𝜑
abbid.2 (𝜑 → (𝜓𝜒))
Assertion
Ref Expression
abbid (𝜑 → {𝑥𝜓} = {𝑥𝜒})

Proof of Theorem abbid
StepHypRef Expression
1 abbid.1 . . 3 𝑥𝜑
2 abbid.2 . . 3 (𝜑 → (𝜓𝜒))
31, 2alrimi 1510 . 2 (𝜑 → ∀𝑥(𝜓𝜒))
4 abbi 2280 . 2 (∀𝑥(𝜓𝜒) ↔ {𝑥𝜓} = {𝑥𝜒})
53, 4sylib 121 1 (𝜑 → {𝑥𝜓} = {𝑥𝜒})
Colors of variables: wff set class
Syntax hints:  wi 4  wb 104  wal 1341   = wceq 1343  wnf 1448  {cab 2151
This theorem was proved from axioms:  ax-mp 5  ax-1 6  ax-2 7  ax-ia1 105  ax-ia2 106  ax-ia3 107  ax-5 1435  ax-7 1436  ax-gen 1437  ax-ie1 1481  ax-ie2 1482  ax-8 1492  ax-11 1494  ax-4 1498  ax-17 1514  ax-i9 1518  ax-ial 1522  ax-i5r 1523  ax-ext 2147
This theorem depends on definitions:  df-bi 116  df-tru 1346  df-nf 1449  df-sb 1751  df-clab 2152  df-cleq 2158
This theorem is referenced by:  abbidv  2284  rabeqf  2716  sbcbid  3008
  Copyright terms: Public domain W3C validator