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| Mirrors > Home > ILE Home > Th. List > vprc | GIF version | ||
| 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.) |
| Ref | Expression |
|---|---|
| vprc | ⊢ ¬ V ∈ V |
| Step | Hyp | Ref | Expression |
|---|---|---|---|
| 1 | vnex 4214 | . 2 ⊢ ¬ ∃𝑥 𝑥 = V | |
| 2 | isset 2806 | . 2 ⊢ (V ∈ V ↔ ∃𝑥 𝑥 = V) | |
| 3 | 1, 2 | mtbir 675 | 1 ⊢ ¬ V ∈ V |
| Colors of variables: wff set class |
| Syntax hints: ¬ wn 3 = wceq 1395 ∃wex 1538 ∈ wcel 2200 Vcvv 2799 |
| 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 4201 |
| 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 2801 |
| This theorem is referenced by: nvel 4216 intexr 4233 intnexr 4234 abnex 4537 snnex 4538 ruALT 4642 dcextest 4672 iprc 4992 snexxph 7113 elfi2 7135 fi0 7138 |
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