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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 4183 | . 2 ⊢ ¬ ∃𝑥 𝑥 = V | |
| 2 | isset 2780 | . 2 ⊢ (V ∈ V ↔ ∃𝑥 𝑥 = V) | |
| 3 | 1, 2 | mtbir 673 | 1 ⊢ ¬ V ∈ V |
| Colors of variables: wff set class |
| Syntax hints: ¬ wn 3 = wceq 1373 ∃wex 1516 ∈ wcel 2177 Vcvv 2773 |
| 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 1471 ax-gen 1473 ax-ie1 1517 ax-ie2 1518 ax-8 1528 ax-4 1534 ax-17 1550 ax-i9 1554 ax-ial 1558 ax-13 2179 ax-14 2180 ax-ext 2188 ax-sep 4170 |
| This theorem depends on definitions: df-bi 117 df-tru 1376 df-fal 1379 df-nf 1485 df-sb 1787 df-clab 2193 df-cleq 2199 df-clel 2202 df-v 2775 |
| This theorem is referenced by: nvel 4185 intexr 4202 intnexr 4203 abnex 4502 snnex 4503 ruALT 4607 dcextest 4637 iprc 4956 snexxph 7067 elfi2 7089 fi0 7092 |
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