Mathbox for BJ |
< Previous
Next >
Nearby theorems |
||
Mirrors > Home > MPE Home > Th. List > Mathboxes > bj-hbaeb2 | Structured version Visualization version GIF version |
Description: Biconditional version of a form of hbae 2449 with commuted quantifiers, not requiring ax-11 2157. (Contributed by BJ, 12-Dec-2019.) (Proof modification is discouraged.) |
Ref | Expression |
---|---|
bj-hbaeb2 | ⊢ (∀𝑥 𝑥 = 𝑦 ↔ ∀𝑥∀𝑧 𝑥 = 𝑦) |
Step | Hyp | Ref | Expression |
---|---|---|---|
1 | sp 2178 | . . . . 5 ⊢ (∀𝑥 𝑥 = 𝑦 → 𝑥 = 𝑦) | |
2 | axc9 2396 | . . . . 5 ⊢ (¬ ∀𝑧 𝑧 = 𝑥 → (¬ ∀𝑧 𝑧 = 𝑦 → (𝑥 = 𝑦 → ∀𝑧 𝑥 = 𝑦))) | |
3 | 1, 2 | syl7 74 | . . . 4 ⊢ (¬ ∀𝑧 𝑧 = 𝑥 → (¬ ∀𝑧 𝑧 = 𝑦 → (∀𝑥 𝑥 = 𝑦 → ∀𝑧 𝑥 = 𝑦))) |
4 | axc11r 2382 | . . . 4 ⊢ (∀𝑧 𝑧 = 𝑥 → (∀𝑥 𝑥 = 𝑦 → ∀𝑧 𝑥 = 𝑦)) | |
5 | axc11 2448 | . . . . . 6 ⊢ (∀𝑥 𝑥 = 𝑦 → (∀𝑥 𝑥 = 𝑦 → ∀𝑦 𝑥 = 𝑦)) | |
6 | 5 | pm2.43i 52 | . . . . 5 ⊢ (∀𝑥 𝑥 = 𝑦 → ∀𝑦 𝑥 = 𝑦) |
7 | axc11r 2382 | . . . . 5 ⊢ (∀𝑧 𝑧 = 𝑦 → (∀𝑦 𝑥 = 𝑦 → ∀𝑧 𝑥 = 𝑦)) | |
8 | 6, 7 | syl5 34 | . . . 4 ⊢ (∀𝑧 𝑧 = 𝑦 → (∀𝑥 𝑥 = 𝑦 → ∀𝑧 𝑥 = 𝑦)) |
9 | 3, 4, 8 | pm2.61ii 185 | . . 3 ⊢ (∀𝑥 𝑥 = 𝑦 → ∀𝑧 𝑥 = 𝑦) |
10 | 9 | axc4i 2337 | . 2 ⊢ (∀𝑥 𝑥 = 𝑦 → ∀𝑥∀𝑧 𝑥 = 𝑦) |
11 | sp 2178 | . . 3 ⊢ (∀𝑧 𝑥 = 𝑦 → 𝑥 = 𝑦) | |
12 | 11 | alimi 1808 | . 2 ⊢ (∀𝑥∀𝑧 𝑥 = 𝑦 → ∀𝑥 𝑥 = 𝑦) |
13 | 10, 12 | impbii 211 | 1 ⊢ (∀𝑥 𝑥 = 𝑦 ↔ ∀𝑥∀𝑧 𝑥 = 𝑦) |
Colors of variables: wff setvar class |
Syntax hints: ¬ wn 3 → wi 4 ↔ wb 208 ∀wal 1531 |
This theorem was proved from axioms: ax-mp 5 ax-1 6 ax-2 7 ax-3 8 ax-gen 1792 ax-4 1806 ax-5 1907 ax-6 1966 ax-7 2011 ax-10 2141 ax-12 2173 ax-13 2386 |
This theorem depends on definitions: df-bi 209 df-an 399 df-or 844 df-tru 1536 df-ex 1777 df-nf 1781 |
This theorem is referenced by: bj-hbaeb 34137 bj-dvv 34139 |
Copyright terms: Public domain | W3C validator |