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Mirrors > Home > ILE Home > Th. List > eupickb | GIF version |
Description: Existential uniqueness "pick" showing wff equivalence. (Contributed by NM, 25-Nov-1994.) |
Ref | Expression |
---|---|
eupickb | ⊢ ((∃!𝑥𝜑 ∧ ∃!𝑥𝜓 ∧ ∃𝑥(𝜑 ∧ 𝜓)) → (𝜑 ↔ 𝜓)) |
Step | Hyp | Ref | Expression |
---|---|---|---|
1 | eupick 2054 | . . 3 ⊢ ((∃!𝑥𝜑 ∧ ∃𝑥(𝜑 ∧ 𝜓)) → (𝜑 → 𝜓)) | |
2 | 1 | 3adant2 983 | . 2 ⊢ ((∃!𝑥𝜑 ∧ ∃!𝑥𝜓 ∧ ∃𝑥(𝜑 ∧ 𝜓)) → (𝜑 → 𝜓)) |
3 | 3simpc 963 | . . 3 ⊢ ((∃!𝑥𝜑 ∧ ∃!𝑥𝜓 ∧ ∃𝑥(𝜑 ∧ 𝜓)) → (∃!𝑥𝜓 ∧ ∃𝑥(𝜑 ∧ 𝜓))) | |
4 | pm3.22 263 | . . . . 5 ⊢ ((𝜑 ∧ 𝜓) → (𝜓 ∧ 𝜑)) | |
5 | 4 | eximi 1562 | . . . 4 ⊢ (∃𝑥(𝜑 ∧ 𝜓) → ∃𝑥(𝜓 ∧ 𝜑)) |
6 | 5 | anim2i 337 | . . 3 ⊢ ((∃!𝑥𝜓 ∧ ∃𝑥(𝜑 ∧ 𝜓)) → (∃!𝑥𝜓 ∧ ∃𝑥(𝜓 ∧ 𝜑))) |
7 | eupick 2054 | . . 3 ⊢ ((∃!𝑥𝜓 ∧ ∃𝑥(𝜓 ∧ 𝜑)) → (𝜓 → 𝜑)) | |
8 | 3, 6, 7 | 3syl 17 | . 2 ⊢ ((∃!𝑥𝜑 ∧ ∃!𝑥𝜓 ∧ ∃𝑥(𝜑 ∧ 𝜓)) → (𝜓 → 𝜑)) |
9 | 2, 8 | impbid 128 | 1 ⊢ ((∃!𝑥𝜑 ∧ ∃!𝑥𝜓 ∧ ∃𝑥(𝜑 ∧ 𝜓)) → (𝜑 ↔ 𝜓)) |
Colors of variables: wff set class |
Syntax hints: → wi 4 ∧ wa 103 ↔ wb 104 ∧ w3a 945 ∃wex 1451 ∃!weu 1975 |
This theorem was proved from axioms: ax-1 5 ax-2 6 ax-mp 7 ax-ia1 105 ax-ia2 106 ax-ia3 107 ax-io 681 ax-5 1406 ax-7 1407 ax-gen 1408 ax-ie1 1452 ax-ie2 1453 ax-8 1465 ax-10 1466 ax-11 1467 ax-i12 1468 ax-bndl 1469 ax-4 1470 ax-17 1489 ax-i9 1493 ax-ial 1497 ax-i5r 1498 |
This theorem depends on definitions: df-bi 116 df-3an 947 df-nf 1420 df-sb 1719 df-eu 1978 df-mo 1979 |
This theorem is referenced by: (None) |
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