| Step | Hyp | Ref
| Expression |
| 1 | | axpowndlem4 10619 |
. 2
⊢ (¬
∀𝑦 𝑦 = 𝑥 → (¬ ∀𝑦 𝑦 = 𝑧 → (¬ 𝑥 = 𝑦 → ∃𝑥∀𝑦(∀𝑥(∃𝑧 𝑥 ∈ 𝑦 → ∀𝑦 𝑥 ∈ 𝑧) → 𝑦 ∈ 𝑥)))) |
| 2 | | axpowndlem1 10616 |
. . 3
⊢
(∀𝑥 𝑥 = 𝑦 → (¬ 𝑥 = 𝑦 → ∃𝑥∀𝑦(∀𝑥(∃𝑧 𝑥 ∈ 𝑦 → ∀𝑦 𝑥 ∈ 𝑧) → 𝑦 ∈ 𝑥))) |
| 3 | 2 | aecoms 2433 |
. 2
⊢
(∀𝑦 𝑦 = 𝑥 → (¬ 𝑥 = 𝑦 → ∃𝑥∀𝑦(∀𝑥(∃𝑧 𝑥 ∈ 𝑦 → ∀𝑦 𝑥 ∈ 𝑧) → 𝑦 ∈ 𝑥))) |
| 4 | 2 | a1d 25 |
. . 3
⊢
(∀𝑥 𝑥 = 𝑦 → (∀𝑦 𝑦 = 𝑧 → (¬ 𝑥 = 𝑦 → ∃𝑥∀𝑦(∀𝑥(∃𝑧 𝑥 ∈ 𝑦 → ∀𝑦 𝑥 ∈ 𝑧) → 𝑦 ∈ 𝑥)))) |
| 5 | | nfnae 2439 |
. . . . . . . 8
⊢
Ⅎ𝑦 ¬
∀𝑥 𝑥 = 𝑦 |
| 6 | | nfae 2438 |
. . . . . . . 8
⊢
Ⅎ𝑦∀𝑦 𝑦 = 𝑧 |
| 7 | 5, 6 | nfan 1899 |
. . . . . . 7
⊢
Ⅎ𝑦(¬
∀𝑥 𝑥 = 𝑦 ∧ ∀𝑦 𝑦 = 𝑧) |
| 8 | | el 5417 |
. . . . . . . . . . . . 13
⊢
∃𝑤 𝑥 ∈ 𝑤 |
| 9 | | nfcvf2 2927 |
. . . . . . . . . . . . . . 15
⊢ (¬
∀𝑥 𝑥 = 𝑦 → Ⅎ𝑦𝑥) |
| 10 | | nfcvd 2900 |
. . . . . . . . . . . . . . 15
⊢ (¬
∀𝑥 𝑥 = 𝑦 → Ⅎ𝑦𝑤) |
| 11 | 9, 10 | nfeld 2911 |
. . . . . . . . . . . . . 14
⊢ (¬
∀𝑥 𝑥 = 𝑦 → Ⅎ𝑦 𝑥 ∈ 𝑤) |
| 12 | | elequ2 2124 |
. . . . . . . . . . . . . . 15
⊢ (𝑤 = 𝑦 → (𝑥 ∈ 𝑤 ↔ 𝑥 ∈ 𝑦)) |
| 13 | 12 | a1i 11 |
. . . . . . . . . . . . . 14
⊢ (¬
∀𝑥 𝑥 = 𝑦 → (𝑤 = 𝑦 → (𝑥 ∈ 𝑤 ↔ 𝑥 ∈ 𝑦))) |
| 14 | 5, 11, 13 | cbvexd 2413 |
. . . . . . . . . . . . 13
⊢ (¬
∀𝑥 𝑥 = 𝑦 → (∃𝑤 𝑥 ∈ 𝑤 ↔ ∃𝑦 𝑥 ∈ 𝑦)) |
| 15 | 8, 14 | mpbii 233 |
. . . . . . . . . . . 12
⊢ (¬
∀𝑥 𝑥 = 𝑦 → ∃𝑦 𝑥 ∈ 𝑦) |
| 16 | 15 | 19.8ad 2183 |
. . . . . . . . . . 11
⊢ (¬
∀𝑥 𝑥 = 𝑦 → ∃𝑥∃𝑦 𝑥 ∈ 𝑦) |
| 17 | | df-ex 1780 |
. . . . . . . . . . 11
⊢
(∃𝑥∃𝑦 𝑥 ∈ 𝑦 ↔ ¬ ∀𝑥 ¬ ∃𝑦 𝑥 ∈ 𝑦) |
| 18 | 16, 17 | sylib 218 |
. . . . . . . . . 10
⊢ (¬
∀𝑥 𝑥 = 𝑦 → ¬ ∀𝑥 ¬ ∃𝑦 𝑥 ∈ 𝑦) |
| 19 | 18 | adantr 480 |
. . . . . . . . 9
⊢ ((¬
∀𝑥 𝑥 = 𝑦 ∧ ∀𝑦 𝑦 = 𝑧) → ¬ ∀𝑥 ¬ ∃𝑦 𝑥 ∈ 𝑦) |
| 20 | | biidd 262 |
. . . . . . . . . . . . . 14
⊢
(∀𝑦 𝑦 = 𝑧 → (¬ 𝑥 ∈ 𝑦 ↔ ¬ 𝑥 ∈ 𝑦)) |
| 21 | 20 | dral1 2444 |
. . . . . . . . . . . . 13
⊢
(∀𝑦 𝑦 = 𝑧 → (∀𝑦 ¬ 𝑥 ∈ 𝑦 ↔ ∀𝑧 ¬ 𝑥 ∈ 𝑦)) |
| 22 | | alnex 1781 |
. . . . . . . . . . . . 13
⊢
(∀𝑦 ¬
𝑥 ∈ 𝑦 ↔ ¬ ∃𝑦 𝑥 ∈ 𝑦) |
| 23 | | alnex 1781 |
. . . . . . . . . . . . 13
⊢
(∀𝑧 ¬
𝑥 ∈ 𝑦 ↔ ¬ ∃𝑧 𝑥 ∈ 𝑦) |
| 24 | 21, 22, 23 | 3bitr3g 313 |
. . . . . . . . . . . 12
⊢
(∀𝑦 𝑦 = 𝑧 → (¬ ∃𝑦 𝑥 ∈ 𝑦 ↔ ¬ ∃𝑧 𝑥 ∈ 𝑦)) |
| 25 | | nd2 10607 |
. . . . . . . . . . . . 13
⊢
(∀𝑦 𝑦 = 𝑧 → ¬ ∀𝑦 𝑥 ∈ 𝑧) |
| 26 | | mtt 364 |
. . . . . . . . . . . . 13
⊢ (¬
∀𝑦 𝑥 ∈ 𝑧 → (¬ ∃𝑧 𝑥 ∈ 𝑦 ↔ (∃𝑧 𝑥 ∈ 𝑦 → ∀𝑦 𝑥 ∈ 𝑧))) |
| 27 | 25, 26 | syl 17 |
. . . . . . . . . . . 12
⊢
(∀𝑦 𝑦 = 𝑧 → (¬ ∃𝑧 𝑥 ∈ 𝑦 ↔ (∃𝑧 𝑥 ∈ 𝑦 → ∀𝑦 𝑥 ∈ 𝑧))) |
| 28 | 24, 27 | bitrd 279 |
. . . . . . . . . . 11
⊢
(∀𝑦 𝑦 = 𝑧 → (¬ ∃𝑦 𝑥 ∈ 𝑦 ↔ (∃𝑧 𝑥 ∈ 𝑦 → ∀𝑦 𝑥 ∈ 𝑧))) |
| 29 | 28 | dral2 2443 |
. . . . . . . . . 10
⊢
(∀𝑦 𝑦 = 𝑧 → (∀𝑥 ¬ ∃𝑦 𝑥 ∈ 𝑦 ↔ ∀𝑥(∃𝑧 𝑥 ∈ 𝑦 → ∀𝑦 𝑥 ∈ 𝑧))) |
| 30 | 29 | adantl 481 |
. . . . . . . . 9
⊢ ((¬
∀𝑥 𝑥 = 𝑦 ∧ ∀𝑦 𝑦 = 𝑧) → (∀𝑥 ¬ ∃𝑦 𝑥 ∈ 𝑦 ↔ ∀𝑥(∃𝑧 𝑥 ∈ 𝑦 → ∀𝑦 𝑥 ∈ 𝑧))) |
| 31 | 19, 30 | mtbid 324 |
. . . . . . . 8
⊢ ((¬
∀𝑥 𝑥 = 𝑦 ∧ ∀𝑦 𝑦 = 𝑧) → ¬ ∀𝑥(∃𝑧 𝑥 ∈ 𝑦 → ∀𝑦 𝑥 ∈ 𝑧)) |
| 32 | 31 | pm2.21d 121 |
. . . . . . 7
⊢ ((¬
∀𝑥 𝑥 = 𝑦 ∧ ∀𝑦 𝑦 = 𝑧) → (∀𝑥(∃𝑧 𝑥 ∈ 𝑦 → ∀𝑦 𝑥 ∈ 𝑧) → 𝑦 ∈ 𝑥)) |
| 33 | 7, 32 | alrimi 2214 |
. . . . . 6
⊢ ((¬
∀𝑥 𝑥 = 𝑦 ∧ ∀𝑦 𝑦 = 𝑧) → ∀𝑦(∀𝑥(∃𝑧 𝑥 ∈ 𝑦 → ∀𝑦 𝑥 ∈ 𝑧) → 𝑦 ∈ 𝑥)) |
| 34 | 33 | 19.8ad 2183 |
. . . . 5
⊢ ((¬
∀𝑥 𝑥 = 𝑦 ∧ ∀𝑦 𝑦 = 𝑧) → ∃𝑥∀𝑦(∀𝑥(∃𝑧 𝑥 ∈ 𝑦 → ∀𝑦 𝑥 ∈ 𝑧) → 𝑦 ∈ 𝑥)) |
| 35 | 34 | a1d 25 |
. . . 4
⊢ ((¬
∀𝑥 𝑥 = 𝑦 ∧ ∀𝑦 𝑦 = 𝑧) → (¬ 𝑥 = 𝑦 → ∃𝑥∀𝑦(∀𝑥(∃𝑧 𝑥 ∈ 𝑦 → ∀𝑦 𝑥 ∈ 𝑧) → 𝑦 ∈ 𝑥))) |
| 36 | 35 | ex 412 |
. . 3
⊢ (¬
∀𝑥 𝑥 = 𝑦 → (∀𝑦 𝑦 = 𝑧 → (¬ 𝑥 = 𝑦 → ∃𝑥∀𝑦(∀𝑥(∃𝑧 𝑥 ∈ 𝑦 → ∀𝑦 𝑥 ∈ 𝑧) → 𝑦 ∈ 𝑥)))) |
| 37 | 4, 36 | pm2.61i 182 |
. 2
⊢
(∀𝑦 𝑦 = 𝑧 → (¬ 𝑥 = 𝑦 → ∃𝑥∀𝑦(∀𝑥(∃𝑧 𝑥 ∈ 𝑦 → ∀𝑦 𝑥 ∈ 𝑧) → 𝑦 ∈ 𝑥))) |
| 38 | 1, 3, 37 | pm2.61ii 183 |
1
⊢ (¬
𝑥 = 𝑦 → ∃𝑥∀𝑦(∀𝑥(∃𝑧 𝑥 ∈ 𝑦 → ∀𝑦 𝑥 ∈ 𝑧) → 𝑦 ∈ 𝑥)) |