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| Mirrors > Home > ILE Home > Th. List > hbald | GIF version | ||
| Description: Deduction form of bound-variable hypothesis builder hbal 1491. (Contributed by NM, 2-Jan-2002.) | 
| Ref | Expression | 
|---|---|
| hbald.1 | ⊢ (𝜑 → ∀𝑦𝜑) | 
| hbald.2 | ⊢ (𝜑 → (𝜓 → ∀𝑥𝜓)) | 
| Ref | Expression | 
|---|---|
| hbald | ⊢ (𝜑 → (∀𝑦𝜓 → ∀𝑥∀𝑦𝜓)) | 
| Step | Hyp | Ref | Expression | 
|---|---|---|---|
| 1 | hbald.1 | . . 3 ⊢ (𝜑 → ∀𝑦𝜑) | |
| 2 | hbald.2 | . . 3 ⊢ (𝜑 → (𝜓 → ∀𝑥𝜓)) | |
| 3 | 1, 2 | alimdh 1481 | . 2 ⊢ (𝜑 → (∀𝑦𝜓 → ∀𝑦∀𝑥𝜓)) | 
| 4 | ax-7 1462 | . 2 ⊢ (∀𝑦∀𝑥𝜓 → ∀𝑥∀𝑦𝜓) | |
| 5 | 3, 4 | syl6 33 | 1 ⊢ (𝜑 → (∀𝑦𝜓 → ∀𝑥∀𝑦𝜓)) | 
| Colors of variables: wff set class | 
| Syntax hints: → wi 4 ∀wal 1362 | 
| This theorem was proved from axioms: ax-mp 5 ax-1 6 ax-2 7 ax-5 1461 ax-7 1462 ax-gen 1463 | 
| This theorem is referenced by: nfald 1774 dvelimfALT2 1831 | 
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