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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 4246 | . 2 ⊢ ¬ ∃𝑥 𝑥 = V | |
| 2 | isset 2822 | . 2 ⊢ (V ∈ V ↔ ∃𝑥 𝑥 = V) | |
| 3 | 1, 2 | mtbir 678 | 1 ⊢ ¬ V ∈ V |
| Colors of variables: wff set class |
| Syntax hints: ¬ wn 3 = wceq 1398 ∃wex 1541 ∈ wcel 2205 Vcvv 2815 |
| 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 1496 ax-gen 1498 ax-ie1 1542 ax-ie2 1543 ax-8 1553 ax-4 1559 ax-17 1575 ax-i9 1579 ax-ial 1583 ax-13 2207 ax-14 2208 ax-ext 2216 ax-sep 4233 |
| This theorem depends on definitions: df-bi 117 df-tru 1401 df-fal 1404 df-nf 1510 df-sb 1812 df-clab 2221 df-cleq 2227 df-clel 2230 df-v 2817 |
| This theorem is referenced by: nvel 4248 intexr 4267 intnexr 4268 abnex 4573 snnex 4574 ruALT 4678 dcextest 4708 iprc 5031 opabn1stprc 6402 snexxph 7233 elfi2 7272 fi0 7275 |
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