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| Mirrors > Home > ILE Home > Th. List > eqv | GIF version | ||
| Description: The universe contains every set. (Contributed by NM, 11-Sep-2006.) |
| Ref | Expression |
|---|---|
| eqv | ⊢ (𝐴 = V ↔ ∀𝑥 𝑥 ∈ 𝐴) |
| Step | Hyp | Ref | Expression |
|---|---|---|---|
| 1 | dfcleq 2198 | . 2 ⊢ (𝐴 = V ↔ ∀𝑥(𝑥 ∈ 𝐴 ↔ 𝑥 ∈ V)) | |
| 2 | vex 2774 | . . . 4 ⊢ 𝑥 ∈ V | |
| 3 | 2 | tbt 247 | . . 3 ⊢ (𝑥 ∈ 𝐴 ↔ (𝑥 ∈ 𝐴 ↔ 𝑥 ∈ V)) |
| 4 | 3 | albii 1492 | . 2 ⊢ (∀𝑥 𝑥 ∈ 𝐴 ↔ ∀𝑥(𝑥 ∈ 𝐴 ↔ 𝑥 ∈ V)) |
| 5 | 1, 4 | bitr4i 187 | 1 ⊢ (𝐴 = V ↔ ∀𝑥 𝑥 ∈ 𝐴) |
| Colors of variables: wff set class |
| Syntax hints: ↔ wb 105 ∀wal 1370 = wceq 1372 ∈ wcel 2175 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-5 1469 ax-gen 1471 ax-ie1 1515 ax-ie2 1516 ax-8 1526 ax-4 1532 ax-17 1548 ax-i9 1552 ax-ial 1556 ax-ext 2186 |
| This theorem depends on definitions: df-bi 117 df-sb 1785 df-clab 2191 df-cleq 2197 df-clel 2200 df-v 2773 |
| This theorem is referenced by: setindel 4584 dmi 4891 |
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