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Theorem vprc 4221
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 4220 . 2 ¬ ∃𝑥 𝑥 = V
2 isset 2809 . 2 (V ∈ V ↔ ∃𝑥 𝑥 = V)
31, 2mtbir 677 1 ¬ V ∈ V
Colors of variables: wff set class
Syntax hints:  ¬ wn 3   = wceq 1397  wex 1540  wcel 2202  Vcvv 2802
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 619  ax-in2 620  ax-5 1495  ax-gen 1497  ax-ie1 1541  ax-ie2 1542  ax-8 1552  ax-4 1558  ax-17 1574  ax-i9 1578  ax-ial 1582  ax-13 2204  ax-14 2205  ax-ext 2213  ax-sep 4207
This theorem depends on definitions:  df-bi 117  df-tru 1400  df-fal 1403  df-nf 1509  df-sb 1811  df-clab 2218  df-cleq 2224  df-clel 2227  df-v 2804
This theorem is referenced by:  nvel  4222  intexr  4240  intnexr  4241  abnex  4544  snnex  4545  ruALT  4649  dcextest  4679  iprc  5001  opabn1stprc  6357  snexxph  7148  elfi2  7170  fi0  7173
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