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| Mirrors > Home > ILE Home > Th. List > ruALT | GIF version | ||
| Description: Alternate proof of Russell's Paradox ru 3031, simplified using (indirectly) the Axiom of Set Induction ax-setind 4641. (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 4226 | . . 3 ⊢ ¬ V ∈ V | |
| 2 | df-nel 2499 | . . 3 ⊢ (V ∉ V ↔ ¬ V ∈ V) | |
| 3 | 1, 2 | mpbir 146 | . 2 ⊢ V ∉ V |
| 4 | ruv 4654 | . . 3 ⊢ {𝑥 ∣ 𝑥 ∉ 𝑥} = V | |
| 5 | neleq1 2502 | . . 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 1398 ∈ wcel 2202 {cab 2217 ∉ wnel 2498 Vcvv 2803 |
| 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-io 717 ax-5 1496 ax-7 1497 ax-gen 1498 ax-ie1 1542 ax-ie2 1543 ax-8 1553 ax-10 1554 ax-11 1555 ax-i12 1556 ax-bndl 1558 ax-4 1559 ax-17 1575 ax-i9 1579 ax-ial 1583 ax-i5r 1584 ax-13 2204 ax-14 2205 ax-ext 2213 ax-sep 4212 ax-setind 4641 |
| This theorem depends on definitions: df-bi 117 df-3an 1007 df-tru 1401 df-fal 1404 df-nf 1510 df-sb 1811 df-clab 2218 df-cleq 2224 df-clel 2227 df-nfc 2364 df-ne 2404 df-nel 2499 df-ral 2516 df-v 2805 df-dif 3203 df-sn 3679 |
| This theorem is referenced by: (None) |
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