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Theorem vprc 4161
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 4160 . 2 ¬ ∃𝑥 𝑥 = V
2 isset 2766 . 2 (V ∈ V ↔ ∃𝑥 𝑥 = V)
31, 2mtbir 672 1 ¬ V ∈ V
Colors of variables: wff set class
Syntax hints:  ¬ wn 3   = wceq 1364  wex 1503  wcel 2164  Vcvv 2760
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 615  ax-in2 616  ax-5 1458  ax-gen 1460  ax-ie1 1504  ax-ie2 1505  ax-8 1515  ax-4 1521  ax-17 1537  ax-i9 1541  ax-ial 1545  ax-13 2166  ax-14 2167  ax-ext 2175  ax-sep 4147
This theorem depends on definitions:  df-bi 117  df-tru 1367  df-fal 1370  df-nf 1472  df-sb 1774  df-clab 2180  df-cleq 2186  df-clel 2189  df-v 2762
This theorem is referenced by:  nvel  4162  intexr  4179  intnexr  4180  abnex  4478  snnex  4479  ruALT  4583  dcextest  4613  iprc  4930  snexxph  7009  elfi2  7031  fi0  7034
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