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Mirrors > Home > ILE Home > Th. List > setindel | GIF version |
Description: ∈-Induction in terms of membership in a class. (Contributed by Mario Carneiro and Jim Kingdon, 22-Oct-2018.) |
Ref | Expression |
---|---|
setindel | ⊢ (∀𝑥(∀𝑦(𝑦 ∈ 𝑥 → 𝑦 ∈ 𝑆) → 𝑥 ∈ 𝑆) → 𝑆 = V) |
Step | Hyp | Ref | Expression |
---|---|---|---|
1 | clelsb1 2282 | . . . . . . 7 ⊢ ([𝑦 / 𝑥]𝑥 ∈ 𝑆 ↔ 𝑦 ∈ 𝑆) | |
2 | 1 | ralbii 2483 | . . . . . 6 ⊢ (∀𝑦 ∈ 𝑥 [𝑦 / 𝑥]𝑥 ∈ 𝑆 ↔ ∀𝑦 ∈ 𝑥 𝑦 ∈ 𝑆) |
3 | df-ral 2460 | . . . . . 6 ⊢ (∀𝑦 ∈ 𝑥 𝑦 ∈ 𝑆 ↔ ∀𝑦(𝑦 ∈ 𝑥 → 𝑦 ∈ 𝑆)) | |
4 | 2, 3 | bitri 184 | . . . . 5 ⊢ (∀𝑦 ∈ 𝑥 [𝑦 / 𝑥]𝑥 ∈ 𝑆 ↔ ∀𝑦(𝑦 ∈ 𝑥 → 𝑦 ∈ 𝑆)) |
5 | 4 | imbi1i 238 | . . . 4 ⊢ ((∀𝑦 ∈ 𝑥 [𝑦 / 𝑥]𝑥 ∈ 𝑆 → 𝑥 ∈ 𝑆) ↔ (∀𝑦(𝑦 ∈ 𝑥 → 𝑦 ∈ 𝑆) → 𝑥 ∈ 𝑆)) |
6 | 5 | albii 1470 | . . 3 ⊢ (∀𝑥(∀𝑦 ∈ 𝑥 [𝑦 / 𝑥]𝑥 ∈ 𝑆 → 𝑥 ∈ 𝑆) ↔ ∀𝑥(∀𝑦(𝑦 ∈ 𝑥 → 𝑦 ∈ 𝑆) → 𝑥 ∈ 𝑆)) |
7 | ax-setind 4535 | . . 3 ⊢ (∀𝑥(∀𝑦 ∈ 𝑥 [𝑦 / 𝑥]𝑥 ∈ 𝑆 → 𝑥 ∈ 𝑆) → ∀𝑥 𝑥 ∈ 𝑆) | |
8 | 6, 7 | sylbir 135 | . 2 ⊢ (∀𝑥(∀𝑦(𝑦 ∈ 𝑥 → 𝑦 ∈ 𝑆) → 𝑥 ∈ 𝑆) → ∀𝑥 𝑥 ∈ 𝑆) |
9 | eqv 3442 | . 2 ⊢ (𝑆 = V ↔ ∀𝑥 𝑥 ∈ 𝑆) | |
10 | 8, 9 | sylibr 134 | 1 ⊢ (∀𝑥(∀𝑦(𝑦 ∈ 𝑥 → 𝑦 ∈ 𝑆) → 𝑥 ∈ 𝑆) → 𝑆 = V) |
Colors of variables: wff set class |
Syntax hints: → wi 4 ∀wal 1351 = wceq 1353 [wsb 1762 ∈ wcel 2148 ∀wral 2455 Vcvv 2737 |
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-io 709 ax-5 1447 ax-7 1448 ax-gen 1449 ax-ie1 1493 ax-ie2 1494 ax-8 1504 ax-10 1505 ax-11 1506 ax-i12 1507 ax-bndl 1509 ax-4 1510 ax-17 1526 ax-i9 1530 ax-ial 1534 ax-i5r 1535 ax-ext 2159 ax-setind 4535 |
This theorem depends on definitions: df-bi 117 df-tru 1356 df-nf 1461 df-sb 1763 df-clab 2164 df-cleq 2170 df-clel 2173 df-ral 2460 df-v 2739 |
This theorem is referenced by: setind 4537 |
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