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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 4259 | . 2 ⊢ ¬ ∃𝑥 𝑥 = V | |
| 2 | isset 2828 | . 2 ⊢ (V ∈ V ↔ ∃𝑥 𝑥 = V) | |
| 3 | 1, 2 | mtbir 682 | 1 ⊢ ¬ V ∈ V |
| Colors of variables: wff set class |
| Syntax hints: ¬ wn 3 = wceq 1402 ∃wex 1545 ∈ wcel 2209 Vcvv 2821 |
| 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 623 ax-in2 624 ax-5 1500 ax-gen 1502 ax-ie1 1546 ax-ie2 1547 ax-8 1557 ax-4 1563 ax-17 1579 ax-i9 1583 ax-ial 1587 ax-13 2211 ax-14 2212 ax-ext 2220 ax-sep 4244 |
| This theorem depends on definitions: df-bi 117 df-tru 1405 df-fal 1408 df-nf 1514 df-sb 1816 df-clab 2225 df-cleq 2231 df-clel 2234 df-v 2823 |
| This theorem is referenced by: nvel 4261 intexr 4281 intnexr 4282 abnex 4588 snnex 4589 ruALT 4693 dcextest 4723 iprc 5046 opabn1stprc 6419 snexxph 7257 elfi2 7296 fi0 7299 |
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