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| Mirrors > Home > ILE Home > Th. List > ruALT | GIF version | ||
| Description: Alternate proof of Russell's Paradox ru 2996, simplified using (indirectly) the Axiom of Set Induction ax-setind 4583. (Contributed by Alan Sare, 4-Oct-2008.) (Proof modification is discouraged.) (New usage is discouraged.) |
| Ref | Expression |
|---|---|
| ruALT | ⊢ {𝑥 ∣ 𝑥 ∉ 𝑥} ∉ V |
| Step | Hyp | Ref | Expression |
|---|---|---|---|
| 1 | vprc 4175 | . . 3 ⊢ ¬ V ∈ V | |
| 2 | df-nel 2471 | . . 3 ⊢ (V ∉ V ↔ ¬ V ∈ V) | |
| 3 | 1, 2 | mpbir 146 | . 2 ⊢ V ∉ V |
| 4 | ruv 4596 | . . 3 ⊢ {𝑥 ∣ 𝑥 ∉ 𝑥} = V | |
| 5 | neleq1 2474 | . . 3 ⊢ ({𝑥 ∣ 𝑥 ∉ 𝑥} = V → ({𝑥 ∣ 𝑥 ∉ 𝑥} ∉ V ↔ V ∉ V)) | |
| 6 | 4, 5 | ax-mp 5 | . 2 ⊢ ({𝑥 ∣ 𝑥 ∉ 𝑥} ∉ V ↔ V ∉ V) |
| 7 | 3, 6 | mpbir 146 | 1 ⊢ {𝑥 ∣ 𝑥 ∉ 𝑥} ∉ V |
| Colors of variables: wff set class |
| Syntax hints: ¬ wn 3 ↔ wb 105 = wceq 1372 ∈ wcel 2175 {cab 2190 ∉ wnel 2470 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-io 710 ax-5 1469 ax-7 1470 ax-gen 1471 ax-ie1 1515 ax-ie2 1516 ax-8 1526 ax-10 1527 ax-11 1528 ax-i12 1529 ax-bndl 1531 ax-4 1532 ax-17 1548 ax-i9 1552 ax-ial 1556 ax-i5r 1557 ax-13 2177 ax-14 2178 ax-ext 2186 ax-sep 4161 ax-setind 4583 |
| This theorem depends on definitions: df-bi 117 df-3an 982 df-tru 1375 df-fal 1378 df-nf 1483 df-sb 1785 df-clab 2191 df-cleq 2197 df-clel 2200 df-nfc 2336 df-ne 2376 df-nel 2471 df-ral 2488 df-v 2773 df-dif 3167 df-sn 3638 |
| This theorem is referenced by: (None) |
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