| Step | Hyp | Ref
| Expression |
| 1 | | ancom 266 |
. . . . . . 7
⊢
((∀𝑦 ∈
𝐵 ¬ 𝑥𝑅𝑦 ∧ ∀𝑦 ∈ 𝐵 ¬ 𝑤𝑅𝑦) ↔ (∀𝑦 ∈ 𝐵 ¬ 𝑤𝑅𝑦 ∧ ∀𝑦 ∈ 𝐵 ¬ 𝑥𝑅𝑦)) |
| 2 | 1 | anbi2ci 459 |
. . . . . 6
⊢
(((∀𝑦 ∈
𝐵 ¬ 𝑥𝑅𝑦 ∧ ∀𝑦 ∈ 𝐵 ¬ 𝑤𝑅𝑦) ∧ (∀𝑦 ∈ 𝐴 (𝑦𝑅𝑤 → ∃𝑧 ∈ 𝐵 𝑦𝑅𝑧) ∧ ∀𝑦 ∈ 𝐴 (𝑦𝑅𝑥 → ∃𝑧 ∈ 𝐵 𝑦𝑅𝑧))) ↔ ((∀𝑦 ∈ 𝐴 (𝑦𝑅𝑤 → ∃𝑧 ∈ 𝐵 𝑦𝑅𝑧) ∧ ∀𝑦 ∈ 𝐴 (𝑦𝑅𝑥 → ∃𝑧 ∈ 𝐵 𝑦𝑅𝑧)) ∧ (∀𝑦 ∈ 𝐵 ¬ 𝑤𝑅𝑦 ∧ ∀𝑦 ∈ 𝐵 ¬ 𝑥𝑅𝑦))) |
| 3 | | an42 587 |
. . . . . 6
⊢
(((∀𝑦 ∈
𝐵 ¬ 𝑥𝑅𝑦 ∧ ∀𝑦 ∈ 𝐴 (𝑦𝑅𝑥 → ∃𝑧 ∈ 𝐵 𝑦𝑅𝑧)) ∧ (∀𝑦 ∈ 𝐵 ¬ 𝑤𝑅𝑦 ∧ ∀𝑦 ∈ 𝐴 (𝑦𝑅𝑤 → ∃𝑧 ∈ 𝐵 𝑦𝑅𝑧))) ↔ ((∀𝑦 ∈ 𝐵 ¬ 𝑥𝑅𝑦 ∧ ∀𝑦 ∈ 𝐵 ¬ 𝑤𝑅𝑦) ∧ (∀𝑦 ∈ 𝐴 (𝑦𝑅𝑤 → ∃𝑧 ∈ 𝐵 𝑦𝑅𝑧) ∧ ∀𝑦 ∈ 𝐴 (𝑦𝑅𝑥 → ∃𝑧 ∈ 𝐵 𝑦𝑅𝑧)))) |
| 4 | | an42 587 |
. . . . . 6
⊢
(((∀𝑦 ∈
𝐴 (𝑦𝑅𝑤 → ∃𝑧 ∈ 𝐵 𝑦𝑅𝑧) ∧ ∀𝑦 ∈ 𝐵 ¬ 𝑥𝑅𝑦) ∧ (∀𝑦 ∈ 𝐴 (𝑦𝑅𝑥 → ∃𝑧 ∈ 𝐵 𝑦𝑅𝑧) ∧ ∀𝑦 ∈ 𝐵 ¬ 𝑤𝑅𝑦)) ↔ ((∀𝑦 ∈ 𝐴 (𝑦𝑅𝑤 → ∃𝑧 ∈ 𝐵 𝑦𝑅𝑧) ∧ ∀𝑦 ∈ 𝐴 (𝑦𝑅𝑥 → ∃𝑧 ∈ 𝐵 𝑦𝑅𝑧)) ∧ (∀𝑦 ∈ 𝐵 ¬ 𝑤𝑅𝑦 ∧ ∀𝑦 ∈ 𝐵 ¬ 𝑥𝑅𝑦))) |
| 5 | 2, 3, 4 | 3bitr4i 212 |
. . . . 5
⊢
(((∀𝑦 ∈
𝐵 ¬ 𝑥𝑅𝑦 ∧ ∀𝑦 ∈ 𝐴 (𝑦𝑅𝑥 → ∃𝑧 ∈ 𝐵 𝑦𝑅𝑧)) ∧ (∀𝑦 ∈ 𝐵 ¬ 𝑤𝑅𝑦 ∧ ∀𝑦 ∈ 𝐴 (𝑦𝑅𝑤 → ∃𝑧 ∈ 𝐵 𝑦𝑅𝑧))) ↔ ((∀𝑦 ∈ 𝐴 (𝑦𝑅𝑤 → ∃𝑧 ∈ 𝐵 𝑦𝑅𝑧) ∧ ∀𝑦 ∈ 𝐵 ¬ 𝑥𝑅𝑦) ∧ (∀𝑦 ∈ 𝐴 (𝑦𝑅𝑥 → ∃𝑧 ∈ 𝐵 𝑦𝑅𝑧) ∧ ∀𝑦 ∈ 𝐵 ¬ 𝑤𝑅𝑦))) |
| 6 | | ralnex 2485 |
. . . . . . . . 9
⊢
(∀𝑦 ∈
𝐵 ¬ 𝑥𝑅𝑦 ↔ ¬ ∃𝑦 ∈ 𝐵 𝑥𝑅𝑦) |
| 7 | | breq1 4036 |
. . . . . . . . . . . . 13
⊢ (𝑦 = 𝑥 → (𝑦𝑅𝑤 ↔ 𝑥𝑅𝑤)) |
| 8 | | breq1 4036 |
. . . . . . . . . . . . . 14
⊢ (𝑦 = 𝑥 → (𝑦𝑅𝑧 ↔ 𝑥𝑅𝑧)) |
| 9 | 8 | rexbidv 2498 |
. . . . . . . . . . . . 13
⊢ (𝑦 = 𝑥 → (∃𝑧 ∈ 𝐵 𝑦𝑅𝑧 ↔ ∃𝑧 ∈ 𝐵 𝑥𝑅𝑧)) |
| 10 | 7, 9 | imbi12d 234 |
. . . . . . . . . . . 12
⊢ (𝑦 = 𝑥 → ((𝑦𝑅𝑤 → ∃𝑧 ∈ 𝐵 𝑦𝑅𝑧) ↔ (𝑥𝑅𝑤 → ∃𝑧 ∈ 𝐵 𝑥𝑅𝑧))) |
| 11 | 10 | rspcva 2866 |
. . . . . . . . . . 11
⊢ ((𝑥 ∈ 𝐴 ∧ ∀𝑦 ∈ 𝐴 (𝑦𝑅𝑤 → ∃𝑧 ∈ 𝐵 𝑦𝑅𝑧)) → (𝑥𝑅𝑤 → ∃𝑧 ∈ 𝐵 𝑥𝑅𝑧)) |
| 12 | | breq2 4037 |
. . . . . . . . . . . 12
⊢ (𝑦 = 𝑧 → (𝑥𝑅𝑦 ↔ 𝑥𝑅𝑧)) |
| 13 | 12 | cbvrexv 2730 |
. . . . . . . . . . 11
⊢
(∃𝑦 ∈
𝐵 𝑥𝑅𝑦 ↔ ∃𝑧 ∈ 𝐵 𝑥𝑅𝑧) |
| 14 | 11, 13 | imbitrrdi 162 |
. . . . . . . . . 10
⊢ ((𝑥 ∈ 𝐴 ∧ ∀𝑦 ∈ 𝐴 (𝑦𝑅𝑤 → ∃𝑧 ∈ 𝐵 𝑦𝑅𝑧)) → (𝑥𝑅𝑤 → ∃𝑦 ∈ 𝐵 𝑥𝑅𝑦)) |
| 15 | 14 | con3d 632 |
. . . . . . . . 9
⊢ ((𝑥 ∈ 𝐴 ∧ ∀𝑦 ∈ 𝐴 (𝑦𝑅𝑤 → ∃𝑧 ∈ 𝐵 𝑦𝑅𝑧)) → (¬ ∃𝑦 ∈ 𝐵 𝑥𝑅𝑦 → ¬ 𝑥𝑅𝑤)) |
| 16 | 6, 15 | biimtrid 152 |
. . . . . . . 8
⊢ ((𝑥 ∈ 𝐴 ∧ ∀𝑦 ∈ 𝐴 (𝑦𝑅𝑤 → ∃𝑧 ∈ 𝐵 𝑦𝑅𝑧)) → (∀𝑦 ∈ 𝐵 ¬ 𝑥𝑅𝑦 → ¬ 𝑥𝑅𝑤)) |
| 17 | 16 | expimpd 363 |
. . . . . . 7
⊢ (𝑥 ∈ 𝐴 → ((∀𝑦 ∈ 𝐴 (𝑦𝑅𝑤 → ∃𝑧 ∈ 𝐵 𝑦𝑅𝑧) ∧ ∀𝑦 ∈ 𝐵 ¬ 𝑥𝑅𝑦) → ¬ 𝑥𝑅𝑤)) |
| 18 | 17 | ad2antrl 490 |
. . . . . 6
⊢ ((𝜑 ∧ (𝑥 ∈ 𝐴 ∧ 𝑤 ∈ 𝐴)) → ((∀𝑦 ∈ 𝐴 (𝑦𝑅𝑤 → ∃𝑧 ∈ 𝐵 𝑦𝑅𝑧) ∧ ∀𝑦 ∈ 𝐵 ¬ 𝑥𝑅𝑦) → ¬ 𝑥𝑅𝑤)) |
| 19 | | ralnex 2485 |
. . . . . . . . 9
⊢
(∀𝑦 ∈
𝐵 ¬ 𝑤𝑅𝑦 ↔ ¬ ∃𝑦 ∈ 𝐵 𝑤𝑅𝑦) |
| 20 | | breq1 4036 |
. . . . . . . . . . . . 13
⊢ (𝑦 = 𝑤 → (𝑦𝑅𝑥 ↔ 𝑤𝑅𝑥)) |
| 21 | | breq1 4036 |
. . . . . . . . . . . . . 14
⊢ (𝑦 = 𝑤 → (𝑦𝑅𝑧 ↔ 𝑤𝑅𝑧)) |
| 22 | 21 | rexbidv 2498 |
. . . . . . . . . . . . 13
⊢ (𝑦 = 𝑤 → (∃𝑧 ∈ 𝐵 𝑦𝑅𝑧 ↔ ∃𝑧 ∈ 𝐵 𝑤𝑅𝑧)) |
| 23 | 20, 22 | imbi12d 234 |
. . . . . . . . . . . 12
⊢ (𝑦 = 𝑤 → ((𝑦𝑅𝑥 → ∃𝑧 ∈ 𝐵 𝑦𝑅𝑧) ↔ (𝑤𝑅𝑥 → ∃𝑧 ∈ 𝐵 𝑤𝑅𝑧))) |
| 24 | 23 | rspcva 2866 |
. . . . . . . . . . 11
⊢ ((𝑤 ∈ 𝐴 ∧ ∀𝑦 ∈ 𝐴 (𝑦𝑅𝑥 → ∃𝑧 ∈ 𝐵 𝑦𝑅𝑧)) → (𝑤𝑅𝑥 → ∃𝑧 ∈ 𝐵 𝑤𝑅𝑧)) |
| 25 | | breq2 4037 |
. . . . . . . . . . . 12
⊢ (𝑦 = 𝑧 → (𝑤𝑅𝑦 ↔ 𝑤𝑅𝑧)) |
| 26 | 25 | cbvrexv 2730 |
. . . . . . . . . . 11
⊢
(∃𝑦 ∈
𝐵 𝑤𝑅𝑦 ↔ ∃𝑧 ∈ 𝐵 𝑤𝑅𝑧) |
| 27 | 24, 26 | imbitrrdi 162 |
. . . . . . . . . 10
⊢ ((𝑤 ∈ 𝐴 ∧ ∀𝑦 ∈ 𝐴 (𝑦𝑅𝑥 → ∃𝑧 ∈ 𝐵 𝑦𝑅𝑧)) → (𝑤𝑅𝑥 → ∃𝑦 ∈ 𝐵 𝑤𝑅𝑦)) |
| 28 | 27 | con3d 632 |
. . . . . . . . 9
⊢ ((𝑤 ∈ 𝐴 ∧ ∀𝑦 ∈ 𝐴 (𝑦𝑅𝑥 → ∃𝑧 ∈ 𝐵 𝑦𝑅𝑧)) → (¬ ∃𝑦 ∈ 𝐵 𝑤𝑅𝑦 → ¬ 𝑤𝑅𝑥)) |
| 29 | 19, 28 | biimtrid 152 |
. . . . . . . 8
⊢ ((𝑤 ∈ 𝐴 ∧ ∀𝑦 ∈ 𝐴 (𝑦𝑅𝑥 → ∃𝑧 ∈ 𝐵 𝑦𝑅𝑧)) → (∀𝑦 ∈ 𝐵 ¬ 𝑤𝑅𝑦 → ¬ 𝑤𝑅𝑥)) |
| 30 | 29 | expimpd 363 |
. . . . . . 7
⊢ (𝑤 ∈ 𝐴 → ((∀𝑦 ∈ 𝐴 (𝑦𝑅𝑥 → ∃𝑧 ∈ 𝐵 𝑦𝑅𝑧) ∧ ∀𝑦 ∈ 𝐵 ¬ 𝑤𝑅𝑦) → ¬ 𝑤𝑅𝑥)) |
| 31 | 30 | ad2antll 491 |
. . . . . 6
⊢ ((𝜑 ∧ (𝑥 ∈ 𝐴 ∧ 𝑤 ∈ 𝐴)) → ((∀𝑦 ∈ 𝐴 (𝑦𝑅𝑥 → ∃𝑧 ∈ 𝐵 𝑦𝑅𝑧) ∧ ∀𝑦 ∈ 𝐵 ¬ 𝑤𝑅𝑦) → ¬ 𝑤𝑅𝑥)) |
| 32 | 18, 31 | anim12d 335 |
. . . . 5
⊢ ((𝜑 ∧ (𝑥 ∈ 𝐴 ∧ 𝑤 ∈ 𝐴)) → (((∀𝑦 ∈ 𝐴 (𝑦𝑅𝑤 → ∃𝑧 ∈ 𝐵 𝑦𝑅𝑧) ∧ ∀𝑦 ∈ 𝐵 ¬ 𝑥𝑅𝑦) ∧ (∀𝑦 ∈ 𝐴 (𝑦𝑅𝑥 → ∃𝑧 ∈ 𝐵 𝑦𝑅𝑧) ∧ ∀𝑦 ∈ 𝐵 ¬ 𝑤𝑅𝑦)) → (¬ 𝑥𝑅𝑤 ∧ ¬ 𝑤𝑅𝑥))) |
| 33 | 5, 32 | biimtrid 152 |
. . . 4
⊢ ((𝜑 ∧ (𝑥 ∈ 𝐴 ∧ 𝑤 ∈ 𝐴)) → (((∀𝑦 ∈ 𝐵 ¬ 𝑥𝑅𝑦 ∧ ∀𝑦 ∈ 𝐴 (𝑦𝑅𝑥 → ∃𝑧 ∈ 𝐵 𝑦𝑅𝑧)) ∧ (∀𝑦 ∈ 𝐵 ¬ 𝑤𝑅𝑦 ∧ ∀𝑦 ∈ 𝐴 (𝑦𝑅𝑤 → ∃𝑧 ∈ 𝐵 𝑦𝑅𝑧))) → (¬ 𝑥𝑅𝑤 ∧ ¬ 𝑤𝑅𝑥))) |
| 34 | | supmoti.ti |
. . . . . 6
⊢ ((𝜑 ∧ (𝑢 ∈ 𝐴 ∧ 𝑣 ∈ 𝐴)) → (𝑢 = 𝑣 ↔ (¬ 𝑢𝑅𝑣 ∧ ¬ 𝑣𝑅𝑢))) |
| 35 | 34 | ralrimivva 2579 |
. . . . 5
⊢ (𝜑 → ∀𝑢 ∈ 𝐴 ∀𝑣 ∈ 𝐴 (𝑢 = 𝑣 ↔ (¬ 𝑢𝑅𝑣 ∧ ¬ 𝑣𝑅𝑢))) |
| 36 | | equequ1 1726 |
. . . . . . 7
⊢ (𝑢 = 𝑥 → (𝑢 = 𝑣 ↔ 𝑥 = 𝑣)) |
| 37 | | breq1 4036 |
. . . . . . . . 9
⊢ (𝑢 = 𝑥 → (𝑢𝑅𝑣 ↔ 𝑥𝑅𝑣)) |
| 38 | 37 | notbid 668 |
. . . . . . . 8
⊢ (𝑢 = 𝑥 → (¬ 𝑢𝑅𝑣 ↔ ¬ 𝑥𝑅𝑣)) |
| 39 | | breq2 4037 |
. . . . . . . . 9
⊢ (𝑢 = 𝑥 → (𝑣𝑅𝑢 ↔ 𝑣𝑅𝑥)) |
| 40 | 39 | notbid 668 |
. . . . . . . 8
⊢ (𝑢 = 𝑥 → (¬ 𝑣𝑅𝑢 ↔ ¬ 𝑣𝑅𝑥)) |
| 41 | 38, 40 | anbi12d 473 |
. . . . . . 7
⊢ (𝑢 = 𝑥 → ((¬ 𝑢𝑅𝑣 ∧ ¬ 𝑣𝑅𝑢) ↔ (¬ 𝑥𝑅𝑣 ∧ ¬ 𝑣𝑅𝑥))) |
| 42 | 36, 41 | bibi12d 235 |
. . . . . 6
⊢ (𝑢 = 𝑥 → ((𝑢 = 𝑣 ↔ (¬ 𝑢𝑅𝑣 ∧ ¬ 𝑣𝑅𝑢)) ↔ (𝑥 = 𝑣 ↔ (¬ 𝑥𝑅𝑣 ∧ ¬ 𝑣𝑅𝑥)))) |
| 43 | | equequ2 1727 |
. . . . . . 7
⊢ (𝑣 = 𝑤 → (𝑥 = 𝑣 ↔ 𝑥 = 𝑤)) |
| 44 | | breq2 4037 |
. . . . . . . . 9
⊢ (𝑣 = 𝑤 → (𝑥𝑅𝑣 ↔ 𝑥𝑅𝑤)) |
| 45 | 44 | notbid 668 |
. . . . . . . 8
⊢ (𝑣 = 𝑤 → (¬ 𝑥𝑅𝑣 ↔ ¬ 𝑥𝑅𝑤)) |
| 46 | | breq1 4036 |
. . . . . . . . 9
⊢ (𝑣 = 𝑤 → (𝑣𝑅𝑥 ↔ 𝑤𝑅𝑥)) |
| 47 | 46 | notbid 668 |
. . . . . . . 8
⊢ (𝑣 = 𝑤 → (¬ 𝑣𝑅𝑥 ↔ ¬ 𝑤𝑅𝑥)) |
| 48 | 45, 47 | anbi12d 473 |
. . . . . . 7
⊢ (𝑣 = 𝑤 → ((¬ 𝑥𝑅𝑣 ∧ ¬ 𝑣𝑅𝑥) ↔ (¬ 𝑥𝑅𝑤 ∧ ¬ 𝑤𝑅𝑥))) |
| 49 | 43, 48 | bibi12d 235 |
. . . . . 6
⊢ (𝑣 = 𝑤 → ((𝑥 = 𝑣 ↔ (¬ 𝑥𝑅𝑣 ∧ ¬ 𝑣𝑅𝑥)) ↔ (𝑥 = 𝑤 ↔ (¬ 𝑥𝑅𝑤 ∧ ¬ 𝑤𝑅𝑥)))) |
| 50 | 42, 49 | rspc2v 2881 |
. . . . 5
⊢ ((𝑥 ∈ 𝐴 ∧ 𝑤 ∈ 𝐴) → (∀𝑢 ∈ 𝐴 ∀𝑣 ∈ 𝐴 (𝑢 = 𝑣 ↔ (¬ 𝑢𝑅𝑣 ∧ ¬ 𝑣𝑅𝑢)) → (𝑥 = 𝑤 ↔ (¬ 𝑥𝑅𝑤 ∧ ¬ 𝑤𝑅𝑥)))) |
| 51 | 35, 50 | mpan9 281 |
. . . 4
⊢ ((𝜑 ∧ (𝑥 ∈ 𝐴 ∧ 𝑤 ∈ 𝐴)) → (𝑥 = 𝑤 ↔ (¬ 𝑥𝑅𝑤 ∧ ¬ 𝑤𝑅𝑥))) |
| 52 | 33, 51 | sylibrd 169 |
. . 3
⊢ ((𝜑 ∧ (𝑥 ∈ 𝐴 ∧ 𝑤 ∈ 𝐴)) → (((∀𝑦 ∈ 𝐵 ¬ 𝑥𝑅𝑦 ∧ ∀𝑦 ∈ 𝐴 (𝑦𝑅𝑥 → ∃𝑧 ∈ 𝐵 𝑦𝑅𝑧)) ∧ (∀𝑦 ∈ 𝐵 ¬ 𝑤𝑅𝑦 ∧ ∀𝑦 ∈ 𝐴 (𝑦𝑅𝑤 → ∃𝑧 ∈ 𝐵 𝑦𝑅𝑧))) → 𝑥 = 𝑤)) |
| 53 | 52 | ralrimivva 2579 |
. 2
⊢ (𝜑 → ∀𝑥 ∈ 𝐴 ∀𝑤 ∈ 𝐴 (((∀𝑦 ∈ 𝐵 ¬ 𝑥𝑅𝑦 ∧ ∀𝑦 ∈ 𝐴 (𝑦𝑅𝑥 → ∃𝑧 ∈ 𝐵 𝑦𝑅𝑧)) ∧ (∀𝑦 ∈ 𝐵 ¬ 𝑤𝑅𝑦 ∧ ∀𝑦 ∈ 𝐴 (𝑦𝑅𝑤 → ∃𝑧 ∈ 𝐵 𝑦𝑅𝑧))) → 𝑥 = 𝑤)) |
| 54 | | breq1 4036 |
. . . . . 6
⊢ (𝑥 = 𝑤 → (𝑥𝑅𝑦 ↔ 𝑤𝑅𝑦)) |
| 55 | 54 | notbid 668 |
. . . . 5
⊢ (𝑥 = 𝑤 → (¬ 𝑥𝑅𝑦 ↔ ¬ 𝑤𝑅𝑦)) |
| 56 | 55 | ralbidv 2497 |
. . . 4
⊢ (𝑥 = 𝑤 → (∀𝑦 ∈ 𝐵 ¬ 𝑥𝑅𝑦 ↔ ∀𝑦 ∈ 𝐵 ¬ 𝑤𝑅𝑦)) |
| 57 | | breq2 4037 |
. . . . . 6
⊢ (𝑥 = 𝑤 → (𝑦𝑅𝑥 ↔ 𝑦𝑅𝑤)) |
| 58 | 57 | imbi1d 231 |
. . . . 5
⊢ (𝑥 = 𝑤 → ((𝑦𝑅𝑥 → ∃𝑧 ∈ 𝐵 𝑦𝑅𝑧) ↔ (𝑦𝑅𝑤 → ∃𝑧 ∈ 𝐵 𝑦𝑅𝑧))) |
| 59 | 58 | ralbidv 2497 |
. . . 4
⊢ (𝑥 = 𝑤 → (∀𝑦 ∈ 𝐴 (𝑦𝑅𝑥 → ∃𝑧 ∈ 𝐵 𝑦𝑅𝑧) ↔ ∀𝑦 ∈ 𝐴 (𝑦𝑅𝑤 → ∃𝑧 ∈ 𝐵 𝑦𝑅𝑧))) |
| 60 | 56, 59 | anbi12d 473 |
. . 3
⊢ (𝑥 = 𝑤 → ((∀𝑦 ∈ 𝐵 ¬ 𝑥𝑅𝑦 ∧ ∀𝑦 ∈ 𝐴 (𝑦𝑅𝑥 → ∃𝑧 ∈ 𝐵 𝑦𝑅𝑧)) ↔ (∀𝑦 ∈ 𝐵 ¬ 𝑤𝑅𝑦 ∧ ∀𝑦 ∈ 𝐴 (𝑦𝑅𝑤 → ∃𝑧 ∈ 𝐵 𝑦𝑅𝑧)))) |
| 61 | 60 | rmo4 2957 |
. 2
⊢
(∃*𝑥 ∈
𝐴 (∀𝑦 ∈ 𝐵 ¬ 𝑥𝑅𝑦 ∧ ∀𝑦 ∈ 𝐴 (𝑦𝑅𝑥 → ∃𝑧 ∈ 𝐵 𝑦𝑅𝑧)) ↔ ∀𝑥 ∈ 𝐴 ∀𝑤 ∈ 𝐴 (((∀𝑦 ∈ 𝐵 ¬ 𝑥𝑅𝑦 ∧ ∀𝑦 ∈ 𝐴 (𝑦𝑅𝑥 → ∃𝑧 ∈ 𝐵 𝑦𝑅𝑧)) ∧ (∀𝑦 ∈ 𝐵 ¬ 𝑤𝑅𝑦 ∧ ∀𝑦 ∈ 𝐴 (𝑦𝑅𝑤 → ∃𝑧 ∈ 𝐵 𝑦𝑅𝑧))) → 𝑥 = 𝑤)) |
| 62 | 53, 61 | sylibr 134 |
1
⊢ (𝜑 → ∃*𝑥 ∈ 𝐴 (∀𝑦 ∈ 𝐵 ¬ 𝑥𝑅𝑦 ∧ ∀𝑦 ∈ 𝐴 (𝑦𝑅𝑥 → ∃𝑧 ∈ 𝐵 𝑦𝑅𝑧))) |