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Theorem bj-ru 34250
Description: Remove dependency on ax-13 2386 (and df-v 3497) from Russell's paradox ru 3771 expressed with primitive symbols and with a class variable 𝑉. Note the more economical use of bj-elissetv 34186 instead of isset 3507 to avoid use of df-v 3497. (Contributed by BJ, 12-Oct-2019.) (Proof modification is discouraged.)
Assertion
Ref Expression
bj-ru ¬ {𝑥 ∣ ¬ 𝑥𝑥} ∈ 𝑉

Proof of Theorem bj-ru
Dummy variable 𝑦 is distinct from all other variables.
StepHypRef Expression
1 bj-ru1 34249 . 2 ¬ ∃𝑦 𝑦 = {𝑥 ∣ ¬ 𝑥𝑥}
2 bj-elissetv 34186 . 2 ({𝑥 ∣ ¬ 𝑥𝑥} ∈ 𝑉 → ∃𝑦 𝑦 = {𝑥 ∣ ¬ 𝑥𝑥})
31, 2mto 199 1 ¬ {𝑥 ∣ ¬ 𝑥𝑥} ∈ 𝑉
Colors of variables: wff setvar class
Syntax hints:  ¬ wn 3   = wceq 1533  wex 1776  wcel 2110  {cab 2799
This theorem was proved from axioms:  ax-mp 5  ax-1 6  ax-2 7  ax-3 8  ax-gen 1792  ax-4 1806  ax-5 1907  ax-6 1966  ax-7 2011  ax-8 2112  ax-9 2120  ax-10 2141  ax-11 2156  ax-12 2172  ax-ext 2793
This theorem depends on definitions:  df-bi 209  df-an 399  df-or 844  df-tru 1536  df-ex 1777  df-nf 1781  df-sb 2066  df-clab 2800  df-cleq 2814  df-clel 2893
This theorem is referenced by: (None)
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