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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 4174 | . 2 ⊢ ¬ ∃𝑥 𝑥 = V | |
| 2 | isset 2777 | . 2 ⊢ (V ∈ V ↔ ∃𝑥 𝑥 = V) | |
| 3 | 1, 2 | mtbir 672 | 1 ⊢ ¬ V ∈ V |
| Colors of variables: wff set class |
| Syntax hints: ¬ wn 3 = wceq 1372 ∃wex 1514 ∈ wcel 2175 Vcvv 2771 |
| 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 1469 ax-gen 1471 ax-ie1 1515 ax-ie2 1516 ax-8 1526 ax-4 1532 ax-17 1548 ax-i9 1552 ax-ial 1556 ax-13 2177 ax-14 2178 ax-ext 2186 ax-sep 4161 |
| This theorem depends on definitions: df-bi 117 df-tru 1375 df-fal 1378 df-nf 1483 df-sb 1785 df-clab 2191 df-cleq 2197 df-clel 2200 df-v 2773 |
| This theorem is referenced by: nvel 4176 intexr 4193 intnexr 4194 abnex 4492 snnex 4493 ruALT 4597 dcextest 4627 iprc 4944 snexxph 7034 elfi2 7056 fi0 7059 |
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