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Theorem vprc 4121
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 4120 . 2 ¬ ∃𝑥 𝑥 = V
2 isset 2736 . 2 (V ∈ V ↔ ∃𝑥 𝑥 = V)
31, 2mtbir 666 1 ¬ V ∈ V
Colors of variables: wff set class
Syntax hints:  ¬ wn 3   = wceq 1348  wex 1485  wcel 2141  Vcvv 2730
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-in1 609  ax-in2 610  ax-5 1440  ax-gen 1442  ax-ie1 1486  ax-ie2 1487  ax-8 1497  ax-4 1503  ax-17 1519  ax-i9 1523  ax-ial 1527  ax-13 2143  ax-14 2144  ax-ext 2152  ax-sep 4107
This theorem depends on definitions:  df-bi 116  df-tru 1351  df-fal 1354  df-nf 1454  df-sb 1756  df-clab 2157  df-cleq 2163  df-clel 2166  df-v 2732
This theorem is referenced by:  nvel  4122  intexr  4136  intnexr  4137  abnex  4432  snnex  4433  ruALT  4535  dcextest  4565  iprc  4879  snexxph  6927  elfi2  6949  fi0  6952
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