Proof of Theorem wl-ax11-lem3
Step | Hyp | Ref
| Expression |
1 | | nfna1 2016 |
. 2
⊢
Ⅎ𝑥 ¬
∀𝑥 𝑥 = 𝑦 |
2 | | wl-naev 32481 |
. . . . 5
⊢ (¬
∀𝑥 𝑥 = 𝑦 → ¬ ∀𝑢 𝑢 = 𝑥) |
3 | | nfa1 2015 |
. . . . . . 7
⊢
Ⅎ𝑢∀𝑢 𝑢 = 𝑦 |
4 | | nfna1 2016 |
. . . . . . 7
⊢
Ⅎ𝑢 ¬
∀𝑢 𝑢 = 𝑥 |
5 | 3, 4 | nfan 1816 |
. . . . . 6
⊢
Ⅎ𝑢(∀𝑢 𝑢 = 𝑦 ∧ ¬ ∀𝑢 𝑢 = 𝑥) |
6 | | axc11n 2295 |
. . . . . . . . . . 11
⊢
(∀𝑥 𝑥 = 𝑦 → ∀𝑦 𝑦 = 𝑥) |
7 | | wl-aetr 32496 |
. . . . . . . . . . 11
⊢
(∀𝑦 𝑦 = 𝑢 → (∀𝑦 𝑦 = 𝑥 → ∀𝑢 𝑢 = 𝑥)) |
8 | 6, 7 | syl5 33 |
. . . . . . . . . 10
⊢
(∀𝑦 𝑦 = 𝑢 → (∀𝑥 𝑥 = 𝑦 → ∀𝑢 𝑢 = 𝑥)) |
9 | 8 | aecoms 2300 |
. . . . . . . . 9
⊢
(∀𝑢 𝑢 = 𝑦 → (∀𝑥 𝑥 = 𝑦 → ∀𝑢 𝑢 = 𝑥)) |
10 | 9 | con3d 147 |
. . . . . . . 8
⊢
(∀𝑢 𝑢 = 𝑦 → (¬ ∀𝑢 𝑢 = 𝑥 → ¬ ∀𝑥 𝑥 = 𝑦)) |
11 | 10 | imdistani 722 |
. . . . . . 7
⊢
((∀𝑢 𝑢 = 𝑦 ∧ ¬ ∀𝑢 𝑢 = 𝑥) → (∀𝑢 𝑢 = 𝑦 ∧ ¬ ∀𝑥 𝑥 = 𝑦)) |
12 | | wl-ax11-lem2 32542 |
. . . . . . 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 2069 |
. . . . 5
⊢
((∀𝑢 𝑢 = 𝑦 ∧ ¬ ∀𝑢 𝑢 = 𝑥) → ∀𝑢∀𝑥 𝑢 = 𝑦) |
15 | 2, 14 | sylan2 490 |
. . . 4
⊢
((∀𝑢 𝑢 = 𝑦 ∧ ¬ ∀𝑥 𝑥 = 𝑦) → ∀𝑢∀𝑥 𝑢 = 𝑦) |
16 | 15 | expcom 450 |
. . 3
⊢ (¬
∀𝑥 𝑥 = 𝑦 → (∀𝑢 𝑢 = 𝑦 → ∀𝑢∀𝑥 𝑢 = 𝑦)) |
17 | | ax-wl-11v 32540 |
. . 3
⊢
(∀𝑢∀𝑥 𝑢 = 𝑦 → ∀𝑥∀𝑢 𝑢 = 𝑦) |
18 | 16, 17 | syl6 34 |
. 2
⊢ (¬
∀𝑥 𝑥 = 𝑦 → (∀𝑢 𝑢 = 𝑦 → ∀𝑥∀𝑢 𝑢 = 𝑦)) |
19 | 1, 18 | nf5d 2104 |
1
⊢ (¬
∀𝑥 𝑥 = 𝑦 → Ⅎ𝑥∀𝑢 𝑢 = 𝑦) |