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Theorem vprc 4219
Description: The universal class is not a member of itself (and thus is not a set). Proposition 5.21 of [TakeutiZaring] p. 21; our proof, however, does not depend on the Axiom of Regularity. (Contributed by NM, 23-Aug-1993.)
Assertion
Ref Expression
vprc ¬ V ∈ V

Proof of Theorem vprc
StepHypRef Expression
1 vnex 4218 . 2 ¬ ∃𝑥 𝑥 = V
2 isset 2807 . 2 (V ∈ V ↔ ∃𝑥 𝑥 = V)
31, 2mtbir 675 1 ¬ V ∈ V
Colors of variables: wff set class
Syntax hints:  ¬ wn 3   = wceq 1395  wex 1538  wcel 2200  Vcvv 2800
This theorem was proved from axioms:  ax-mp 5  ax-1 6  ax-2 7  ax-ia1 106  ax-ia2 107  ax-ia3 108  ax-in1 617  ax-in2 618  ax-5 1493  ax-gen 1495  ax-ie1 1539  ax-ie2 1540  ax-8 1550  ax-4 1556  ax-17 1572  ax-i9 1576  ax-ial 1580  ax-13 2202  ax-14 2203  ax-ext 2211  ax-sep 4205
This theorem depends on definitions:  df-bi 117  df-tru 1398  df-fal 1401  df-nf 1507  df-sb 1809  df-clab 2216  df-cleq 2222  df-clel 2225  df-v 2802
This theorem is referenced by:  nvel  4220  intexr  4238  intnexr  4239  abnex  4542  snnex  4543  ruALT  4647  dcextest  4677  iprc  4999  opabn1stprc  6353  snexxph  7140  elfi2  7162  fi0  7165
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