Proof of Theorem wl-ax11-lem3
| Step | Hyp | Ref
| Expression |
| 1 | | nfna1 2152 |
. 2
⊢
Ⅎ𝑥 ¬
∀𝑥 𝑥 = 𝑦 |
| 2 | | naev 2060 |
. . . . 5
⊢ (¬
∀𝑥 𝑥 = 𝑦 → ¬ ∀𝑢 𝑢 = 𝑥) |
| 3 | | nfa1 2151 |
. . . . . . 7
⊢
Ⅎ𝑢∀𝑢 𝑢 = 𝑦 |
| 4 | | nfna1 2152 |
. . . . . . 7
⊢
Ⅎ𝑢 ¬
∀𝑢 𝑢 = 𝑥 |
| 5 | 3, 4 | nfan 1899 |
. . . . . 6
⊢
Ⅎ𝑢(∀𝑢 𝑢 = 𝑦 ∧ ¬ ∀𝑢 𝑢 = 𝑥) |
| 6 | | axc11n 2431 |
. . . . . . . . . . 11
⊢
(∀𝑥 𝑥 = 𝑦 → ∀𝑦 𝑦 = 𝑥) |
| 7 | | wl-aetr 37530 |
. . . . . . . . . . 11
⊢
(∀𝑦 𝑦 = 𝑢 → (∀𝑦 𝑦 = 𝑥 → ∀𝑢 𝑢 = 𝑥)) |
| 8 | 6, 7 | syl5 34 |
. . . . . . . . . 10
⊢
(∀𝑦 𝑦 = 𝑢 → (∀𝑥 𝑥 = 𝑦 → ∀𝑢 𝑢 = 𝑥)) |
| 9 | 8 | aecoms 2433 |
. . . . . . . . 9
⊢
(∀𝑢 𝑢 = 𝑦 → (∀𝑥 𝑥 = 𝑦 → ∀𝑢 𝑢 = 𝑥)) |
| 10 | 9 | con3d 152 |
. . . . . . . 8
⊢
(∀𝑢 𝑢 = 𝑦 → (¬ ∀𝑢 𝑢 = 𝑥 → ¬ ∀𝑥 𝑥 = 𝑦)) |
| 11 | 10 | imdistani 568 |
. . . . . . 7
⊢
((∀𝑢 𝑢 = 𝑦 ∧ ¬ ∀𝑢 𝑢 = 𝑥) → (∀𝑢 𝑢 = 𝑦 ∧ ¬ ∀𝑥 𝑥 = 𝑦)) |
| 12 | | wl-ax11-lem2 37587 |
. . . . . . 7
⊢
((∀𝑢 𝑢 = 𝑦 ∧ ¬ ∀𝑥 𝑥 = 𝑦) → ∀𝑥 𝑢 = 𝑦) |
| 13 | 11, 12 | syl 17 |
. . . . . 6
⊢
((∀𝑢 𝑢 = 𝑦 ∧ ¬ ∀𝑢 𝑢 = 𝑥) → ∀𝑥 𝑢 = 𝑦) |
| 14 | 5, 13 | alrimi 2213 |
. . . . 5
⊢
((∀𝑢 𝑢 = 𝑦 ∧ ¬ ∀𝑢 𝑢 = 𝑥) → ∀𝑢∀𝑥 𝑢 = 𝑦) |
| 15 | 2, 14 | sylan2 593 |
. . . 4
⊢
((∀𝑢 𝑢 = 𝑦 ∧ ¬ ∀𝑥 𝑥 = 𝑦) → ∀𝑢∀𝑥 𝑢 = 𝑦) |
| 16 | 15 | expcom 413 |
. . 3
⊢ (¬
∀𝑥 𝑥 = 𝑦 → (∀𝑢 𝑢 = 𝑦 → ∀𝑢∀𝑥 𝑢 = 𝑦)) |
| 17 | | ax-wl-11v 37585 |
. . 3
⊢
(∀𝑢∀𝑥 𝑢 = 𝑦 → ∀𝑥∀𝑢 𝑢 = 𝑦) |
| 18 | 16, 17 | syl6 35 |
. 2
⊢ (¬
∀𝑥 𝑥 = 𝑦 → (∀𝑢 𝑢 = 𝑦 → ∀𝑥∀𝑢 𝑢 = 𝑦)) |
| 19 | 1, 18 | nf5d 2284 |
1
⊢ (¬
∀𝑥 𝑥 = 𝑦 → Ⅎ𝑥∀𝑢 𝑢 = 𝑦) |