ILE Home Intuitionistic Logic Explorer < Previous   Next >
Nearby theorems
Mirrors  >  Home  >  ILE Home  >  Th. List  >  elex22 GIF version

Theorem elex22 2569
Description: If two classes each contain another class, then both contain some set. (Contributed by Alan Sare, 24-Oct-2011.)
Assertion
Ref Expression
elex22 ((𝐴𝐵𝐴𝐶) → ∃𝑥(𝑥𝐵𝑥𝐶))
Distinct variable groups:   𝑥,𝐴   𝑥,𝐵   𝑥,𝐶

Proof of Theorem elex22
StepHypRef Expression
1 eleq1a 2109 . . . 4 (𝐴𝐵 → (𝑥 = 𝐴𝑥𝐵))
2 eleq1a 2109 . . . 4 (𝐴𝐶 → (𝑥 = 𝐴𝑥𝐶))
31, 2anim12ii 325 . . 3 ((𝐴𝐵𝐴𝐶) → (𝑥 = 𝐴 → (𝑥𝐵𝑥𝐶)))
43alrimiv 1754 . 2 ((𝐴𝐵𝐴𝐶) → ∀𝑥(𝑥 = 𝐴 → (𝑥𝐵𝑥𝐶)))
5 elisset 2568 . . 3 (𝐴𝐵 → ∃𝑥 𝑥 = 𝐴)
65adantr 261 . 2 ((𝐴𝐵𝐴𝐶) → ∃𝑥 𝑥 = 𝐴)
7 exim 1490 . 2 (∀𝑥(𝑥 = 𝐴 → (𝑥𝐵𝑥𝐶)) → (∃𝑥 𝑥 = 𝐴 → ∃𝑥(𝑥𝐵𝑥𝐶)))
84, 6, 7sylc 56 1 ((𝐴𝐵𝐴𝐶) → ∃𝑥(𝑥𝐵𝑥𝐶))
Colors of variables: wff set class
Syntax hints:  wi 4  wa 97  wal 1241   = wceq 1243  wex 1381  wcel 1393
This theorem was proved from axioms:  ax-1 5  ax-2 6  ax-mp 7  ax-ia1 99  ax-ia2 100  ax-ia3 101  ax-5 1336  ax-gen 1338  ax-ie1 1382  ax-ie2 1383  ax-8 1395  ax-4 1400  ax-17 1419  ax-i9 1423  ax-ial 1427  ax-ext 2022
This theorem depends on definitions:  df-bi 110  df-sb 1646  df-clab 2027  df-cleq 2033  df-clel 2036  df-v 2559
This theorem is referenced by: (None)
  Copyright terms: Public domain W3C validator