Proof of Theorem 2uasbanhVD
| Step | Hyp | Ref | Expression | 
|---|
| 1 |  | idn1 44594 | . . . . . . . 8
⊢ (   ((𝑥 = 𝑢 ∧ 𝑦 = 𝑣) ∧ (𝜑 ∧ 𝜓))   ▶   ((𝑥 = 𝑢 ∧ 𝑦 = 𝑣) ∧ (𝜑 ∧ 𝜓))   ) | 
| 2 |  | simpl 482 | . . . . . . . 8
⊢ (((𝑥 = 𝑢 ∧ 𝑦 = 𝑣) ∧ (𝜑 ∧ 𝜓)) → (𝑥 = 𝑢 ∧ 𝑦 = 𝑣)) | 
| 3 | 1, 2 | e1a 44647 | . . . . . . 7
⊢ (   ((𝑥 = 𝑢 ∧ 𝑦 = 𝑣) ∧ (𝜑 ∧ 𝜓))   ▶   (𝑥 = 𝑢 ∧ 𝑦 = 𝑣)   ) | 
| 4 |  | simpr 484 | . . . . . . . . 9
⊢ (((𝑥 = 𝑢 ∧ 𝑦 = 𝑣) ∧ (𝜑 ∧ 𝜓)) → (𝜑 ∧ 𝜓)) | 
| 5 | 1, 4 | e1a 44647 | . . . . . . . 8
⊢ (   ((𝑥 = 𝑢 ∧ 𝑦 = 𝑣) ∧ (𝜑 ∧ 𝜓))   ▶   (𝜑 ∧ 𝜓)   ) | 
| 6 |  | simpl 482 | . . . . . . . 8
⊢ ((𝜑 ∧ 𝜓) → 𝜑) | 
| 7 | 5, 6 | e1a 44647 | . . . . . . 7
⊢ (   ((𝑥 = 𝑢 ∧ 𝑦 = 𝑣) ∧ (𝜑 ∧ 𝜓))   ▶   𝜑   ) | 
| 8 |  | pm3.2 469 | . . . . . . 7
⊢ ((𝑥 = 𝑢 ∧ 𝑦 = 𝑣) → (𝜑 → ((𝑥 = 𝑢 ∧ 𝑦 = 𝑣) ∧ 𝜑))) | 
| 9 | 3, 7, 8 | e11 44708 | . . . . . 6
⊢ (   ((𝑥 = 𝑢 ∧ 𝑦 = 𝑣) ∧ (𝜑 ∧ 𝜓))   ▶   ((𝑥 = 𝑢 ∧ 𝑦 = 𝑣) ∧ 𝜑)   ) | 
| 10 | 9 | in1 44591 | . . . . 5
⊢ (((𝑥 = 𝑢 ∧ 𝑦 = 𝑣) ∧ (𝜑 ∧ 𝜓)) → ((𝑥 = 𝑢 ∧ 𝑦 = 𝑣) ∧ 𝜑)) | 
| 11 | 10 | eximi 1835 | . . . 4
⊢
(∃𝑦((𝑥 = 𝑢 ∧ 𝑦 = 𝑣) ∧ (𝜑 ∧ 𝜓)) → ∃𝑦((𝑥 = 𝑢 ∧ 𝑦 = 𝑣) ∧ 𝜑)) | 
| 12 | 11 | eximi 1835 | . . 3
⊢
(∃𝑥∃𝑦((𝑥 = 𝑢 ∧ 𝑦 = 𝑣) ∧ (𝜑 ∧ 𝜓)) → ∃𝑥∃𝑦((𝑥 = 𝑢 ∧ 𝑦 = 𝑣) ∧ 𝜑)) | 
| 13 |  | simpr 484 | . . . . . . . 8
⊢ ((𝜑 ∧ 𝜓) → 𝜓) | 
| 14 | 5, 13 | e1a 44647 | . . . . . . 7
⊢ (   ((𝑥 = 𝑢 ∧ 𝑦 = 𝑣) ∧ (𝜑 ∧ 𝜓))   ▶   𝜓   ) | 
| 15 |  | pm3.2 469 | . . . . . . 7
⊢ ((𝑥 = 𝑢 ∧ 𝑦 = 𝑣) → (𝜓 → ((𝑥 = 𝑢 ∧ 𝑦 = 𝑣) ∧ 𝜓))) | 
| 16 | 3, 14, 15 | e11 44708 | . . . . . 6
⊢ (   ((𝑥 = 𝑢 ∧ 𝑦 = 𝑣) ∧ (𝜑 ∧ 𝜓))   ▶   ((𝑥 = 𝑢 ∧ 𝑦 = 𝑣) ∧ 𝜓)   ) | 
| 17 | 16 | in1 44591 | . . . . 5
⊢ (((𝑥 = 𝑢 ∧ 𝑦 = 𝑣) ∧ (𝜑 ∧ 𝜓)) → ((𝑥 = 𝑢 ∧ 𝑦 = 𝑣) ∧ 𝜓)) | 
| 18 | 17 | eximi 1835 | . . . 4
⊢
(∃𝑦((𝑥 = 𝑢 ∧ 𝑦 = 𝑣) ∧ (𝜑 ∧ 𝜓)) → ∃𝑦((𝑥 = 𝑢 ∧ 𝑦 = 𝑣) ∧ 𝜓)) | 
| 19 | 18 | eximi 1835 | . . 3
⊢
(∃𝑥∃𝑦((𝑥 = 𝑢 ∧ 𝑦 = 𝑣) ∧ (𝜑 ∧ 𝜓)) → ∃𝑥∃𝑦((𝑥 = 𝑢 ∧ 𝑦 = 𝑣) ∧ 𝜓)) | 
| 20 | 12, 19 | jca 511 | . 2
⊢
(∃𝑥∃𝑦((𝑥 = 𝑢 ∧ 𝑦 = 𝑣) ∧ (𝜑 ∧ 𝜓)) → (∃𝑥∃𝑦((𝑥 = 𝑢 ∧ 𝑦 = 𝑣) ∧ 𝜑) ∧ ∃𝑥∃𝑦((𝑥 = 𝑢 ∧ 𝑦 = 𝑣) ∧ 𝜓))) | 
| 21 |  | 2uasbanhVD.1 | . . 3
⊢ (𝜒 ↔ (∃𝑥∃𝑦((𝑥 = 𝑢 ∧ 𝑦 = 𝑣) ∧ 𝜑) ∧ ∃𝑥∃𝑦((𝑥 = 𝑢 ∧ 𝑦 = 𝑣) ∧ 𝜓))) | 
| 22 | 21 | biimpi 216 | . . . . . . . . 9
⊢ (𝜒 → (∃𝑥∃𝑦((𝑥 = 𝑢 ∧ 𝑦 = 𝑣) ∧ 𝜑) ∧ ∃𝑥∃𝑦((𝑥 = 𝑢 ∧ 𝑦 = 𝑣) ∧ 𝜓))) | 
| 23 | 22 | dfvd1ir 44593 | . . . . . . . 8
⊢ (   𝜒   ▶   (∃𝑥∃𝑦((𝑥 = 𝑢 ∧ 𝑦 = 𝑣) ∧ 𝜑) ∧ ∃𝑥∃𝑦((𝑥 = 𝑢 ∧ 𝑦 = 𝑣) ∧ 𝜓))   ) | 
| 24 |  | simpl 482 | . . . . . . . 8
⊢
((∃𝑥∃𝑦((𝑥 = 𝑢 ∧ 𝑦 = 𝑣) ∧ 𝜑) ∧ ∃𝑥∃𝑦((𝑥 = 𝑢 ∧ 𝑦 = 𝑣) ∧ 𝜓)) → ∃𝑥∃𝑦((𝑥 = 𝑢 ∧ 𝑦 = 𝑣) ∧ 𝜑)) | 
| 25 | 23, 24 | e1a 44647 | . . . . . . 7
⊢ (   𝜒   ▶   ∃𝑥∃𝑦((𝑥 = 𝑢 ∧ 𝑦 = 𝑣) ∧ 𝜑)   ) | 
| 26 |  | simpl 482 | . . . . . . . . . . 11
⊢ (((𝑥 = 𝑢 ∧ 𝑦 = 𝑣) ∧ 𝜑) → (𝑥 = 𝑢 ∧ 𝑦 = 𝑣)) | 
| 27 | 26 | 2eximi 1836 | . . . . . . . . . 10
⊢
(∃𝑥∃𝑦((𝑥 = 𝑢 ∧ 𝑦 = 𝑣) ∧ 𝜑) → ∃𝑥∃𝑦(𝑥 = 𝑢 ∧ 𝑦 = 𝑣)) | 
| 28 | 25, 27 | e1a 44647 | . . . . . . . . 9
⊢ (   𝜒   ▶   ∃𝑥∃𝑦(𝑥 = 𝑢 ∧ 𝑦 = 𝑣)   ) | 
| 29 |  | ax6e2ndeq 44579 | . . . . . . . . . 10
⊢ ((¬
∀𝑥 𝑥 = 𝑦 ∨ 𝑢 = 𝑣) ↔ ∃𝑥∃𝑦(𝑥 = 𝑢 ∧ 𝑦 = 𝑣)) | 
| 30 | 29 | biimpri 228 | . . . . . . . . 9
⊢
(∃𝑥∃𝑦(𝑥 = 𝑢 ∧ 𝑦 = 𝑣) → (¬ ∀𝑥 𝑥 = 𝑦 ∨ 𝑢 = 𝑣)) | 
| 31 | 28, 30 | e1a 44647 | . . . . . . . 8
⊢ (   𝜒   ▶   (¬
∀𝑥 𝑥 = 𝑦 ∨ 𝑢 = 𝑣)   ) | 
| 32 |  | 2sb5nd 44580 | . . . . . . . 8
⊢ ((¬
∀𝑥 𝑥 = 𝑦 ∨ 𝑢 = 𝑣) → ([𝑢 / 𝑥][𝑣 / 𝑦]𝜑 ↔ ∃𝑥∃𝑦((𝑥 = 𝑢 ∧ 𝑦 = 𝑣) ∧ 𝜑))) | 
| 33 | 31, 32 | e1a 44647 | . . . . . . 7
⊢ (   𝜒   ▶   ([𝑢 / 𝑥][𝑣 / 𝑦]𝜑 ↔ ∃𝑥∃𝑦((𝑥 = 𝑢 ∧ 𝑦 = 𝑣) ∧ 𝜑))   ) | 
| 34 |  | biimpr 220 | . . . . . . . 8
⊢ (([𝑢 / 𝑥][𝑣 / 𝑦]𝜑 ↔ ∃𝑥∃𝑦((𝑥 = 𝑢 ∧ 𝑦 = 𝑣) ∧ 𝜑)) → (∃𝑥∃𝑦((𝑥 = 𝑢 ∧ 𝑦 = 𝑣) ∧ 𝜑) → [𝑢 / 𝑥][𝑣 / 𝑦]𝜑)) | 
| 35 | 34 | com12 32 | . . . . . . 7
⊢
(∃𝑥∃𝑦((𝑥 = 𝑢 ∧ 𝑦 = 𝑣) ∧ 𝜑) → (([𝑢 / 𝑥][𝑣 / 𝑦]𝜑 ↔ ∃𝑥∃𝑦((𝑥 = 𝑢 ∧ 𝑦 = 𝑣) ∧ 𝜑)) → [𝑢 / 𝑥][𝑣 / 𝑦]𝜑)) | 
| 36 | 25, 33, 35 | e11 44708 | . . . . . 6
⊢ (   𝜒   ▶   [𝑢 / 𝑥][𝑣 / 𝑦]𝜑   ) | 
| 37 |  | simpr 484 | . . . . . . . 8
⊢
((∃𝑥∃𝑦((𝑥 = 𝑢 ∧ 𝑦 = 𝑣) ∧ 𝜑) ∧ ∃𝑥∃𝑦((𝑥 = 𝑢 ∧ 𝑦 = 𝑣) ∧ 𝜓)) → ∃𝑥∃𝑦((𝑥 = 𝑢 ∧ 𝑦 = 𝑣) ∧ 𝜓)) | 
| 38 | 23, 37 | e1a 44647 | . . . . . . 7
⊢ (   𝜒   ▶   ∃𝑥∃𝑦((𝑥 = 𝑢 ∧ 𝑦 = 𝑣) ∧ 𝜓)   ) | 
| 39 |  | 2sb5nd 44580 | . . . . . . . 8
⊢ ((¬
∀𝑥 𝑥 = 𝑦 ∨ 𝑢 = 𝑣) → ([𝑢 / 𝑥][𝑣 / 𝑦]𝜓 ↔ ∃𝑥∃𝑦((𝑥 = 𝑢 ∧ 𝑦 = 𝑣) ∧ 𝜓))) | 
| 40 | 31, 39 | e1a 44647 | . . . . . . 7
⊢ (   𝜒   ▶   ([𝑢 / 𝑥][𝑣 / 𝑦]𝜓 ↔ ∃𝑥∃𝑦((𝑥 = 𝑢 ∧ 𝑦 = 𝑣) ∧ 𝜓))   ) | 
| 41 |  | biimpr 220 | . . . . . . . 8
⊢ (([𝑢 / 𝑥][𝑣 / 𝑦]𝜓 ↔ ∃𝑥∃𝑦((𝑥 = 𝑢 ∧ 𝑦 = 𝑣) ∧ 𝜓)) → (∃𝑥∃𝑦((𝑥 = 𝑢 ∧ 𝑦 = 𝑣) ∧ 𝜓) → [𝑢 / 𝑥][𝑣 / 𝑦]𝜓)) | 
| 42 | 41 | com12 32 | . . . . . . 7
⊢
(∃𝑥∃𝑦((𝑥 = 𝑢 ∧ 𝑦 = 𝑣) ∧ 𝜓) → (([𝑢 / 𝑥][𝑣 / 𝑦]𝜓 ↔ ∃𝑥∃𝑦((𝑥 = 𝑢 ∧ 𝑦 = 𝑣) ∧ 𝜓)) → [𝑢 / 𝑥][𝑣 / 𝑦]𝜓)) | 
| 43 | 38, 40, 42 | e11 44708 | . . . . . 6
⊢ (   𝜒   ▶   [𝑢 / 𝑥][𝑣 / 𝑦]𝜓   ) | 
| 44 |  | sban 2080 | . . . . . . . 8
⊢ ([𝑣 / 𝑦](𝜑 ∧ 𝜓) ↔ ([𝑣 / 𝑦]𝜑 ∧ [𝑣 / 𝑦]𝜓)) | 
| 45 | 44 | sbbii 2076 | . . . . . . 7
⊢ ([𝑢 / 𝑥][𝑣 / 𝑦](𝜑 ∧ 𝜓) ↔ [𝑢 / 𝑥]([𝑣 / 𝑦]𝜑 ∧ [𝑣 / 𝑦]𝜓)) | 
| 46 |  | sban 2080 | . . . . . . 7
⊢ ([𝑢 / 𝑥]([𝑣 / 𝑦]𝜑 ∧ [𝑣 / 𝑦]𝜓) ↔ ([𝑢 / 𝑥][𝑣 / 𝑦]𝜑 ∧ [𝑢 / 𝑥][𝑣 / 𝑦]𝜓)) | 
| 47 | 45, 46 | bitri 275 | . . . . . 6
⊢ ([𝑢 / 𝑥][𝑣 / 𝑦](𝜑 ∧ 𝜓) ↔ ([𝑢 / 𝑥][𝑣 / 𝑦]𝜑 ∧ [𝑢 / 𝑥][𝑣 / 𝑦]𝜓)) | 
| 48 |  | simplbi2comt 501 | . . . . . . 7
⊢ (([𝑢 / 𝑥][𝑣 / 𝑦](𝜑 ∧ 𝜓) ↔ ([𝑢 / 𝑥][𝑣 / 𝑦]𝜑 ∧ [𝑢 / 𝑥][𝑣 / 𝑦]𝜓)) → ([𝑢 / 𝑥][𝑣 / 𝑦]𝜓 → ([𝑢 / 𝑥][𝑣 / 𝑦]𝜑 → [𝑢 / 𝑥][𝑣 / 𝑦](𝜑 ∧ 𝜓)))) | 
| 49 | 48 | com13 88 | . . . . . 6
⊢ ([𝑢 / 𝑥][𝑣 / 𝑦]𝜑 → ([𝑢 / 𝑥][𝑣 / 𝑦]𝜓 → (([𝑢 / 𝑥][𝑣 / 𝑦](𝜑 ∧ 𝜓) ↔ ([𝑢 / 𝑥][𝑣 / 𝑦]𝜑 ∧ [𝑢 / 𝑥][𝑣 / 𝑦]𝜓)) → [𝑢 / 𝑥][𝑣 / 𝑦](𝜑 ∧ 𝜓)))) | 
| 50 | 36, 43, 47, 49 | e110 44696 | . . . . 5
⊢ (   𝜒   ▶   [𝑢 / 𝑥][𝑣 / 𝑦](𝜑 ∧ 𝜓)   ) | 
| 51 |  | 2sb5nd 44580 | . . . . . 6
⊢ ((¬
∀𝑥 𝑥 = 𝑦 ∨ 𝑢 = 𝑣) → ([𝑢 / 𝑥][𝑣 / 𝑦](𝜑 ∧ 𝜓) ↔ ∃𝑥∃𝑦((𝑥 = 𝑢 ∧ 𝑦 = 𝑣) ∧ (𝜑 ∧ 𝜓)))) | 
| 52 | 31, 51 | e1a 44647 | . . . . 5
⊢ (   𝜒   ▶   ([𝑢 / 𝑥][𝑣 / 𝑦](𝜑 ∧ 𝜓) ↔ ∃𝑥∃𝑦((𝑥 = 𝑢 ∧ 𝑦 = 𝑣) ∧ (𝜑 ∧ 𝜓)))   ) | 
| 53 |  | biimp 215 | . . . . . 6
⊢ (([𝑢 / 𝑥][𝑣 / 𝑦](𝜑 ∧ 𝜓) ↔ ∃𝑥∃𝑦((𝑥 = 𝑢 ∧ 𝑦 = 𝑣) ∧ (𝜑 ∧ 𝜓))) → ([𝑢 / 𝑥][𝑣 / 𝑦](𝜑 ∧ 𝜓) → ∃𝑥∃𝑦((𝑥 = 𝑢 ∧ 𝑦 = 𝑣) ∧ (𝜑 ∧ 𝜓)))) | 
| 54 | 53 | com12 32 | . . . . 5
⊢ ([𝑢 / 𝑥][𝑣 / 𝑦](𝜑 ∧ 𝜓) → (([𝑢 / 𝑥][𝑣 / 𝑦](𝜑 ∧ 𝜓) ↔ ∃𝑥∃𝑦((𝑥 = 𝑢 ∧ 𝑦 = 𝑣) ∧ (𝜑 ∧ 𝜓))) → ∃𝑥∃𝑦((𝑥 = 𝑢 ∧ 𝑦 = 𝑣) ∧ (𝜑 ∧ 𝜓)))) | 
| 55 | 50, 52, 54 | e11 44708 | . . . 4
⊢ (   𝜒   ▶   ∃𝑥∃𝑦((𝑥 = 𝑢 ∧ 𝑦 = 𝑣) ∧ (𝜑 ∧ 𝜓))   ) | 
| 56 | 55 | in1 44591 | . . 3
⊢ (𝜒 → ∃𝑥∃𝑦((𝑥 = 𝑢 ∧ 𝑦 = 𝑣) ∧ (𝜑 ∧ 𝜓))) | 
| 57 | 21, 56 | sylbir 235 | . 2
⊢
((∃𝑥∃𝑦((𝑥 = 𝑢 ∧ 𝑦 = 𝑣) ∧ 𝜑) ∧ ∃𝑥∃𝑦((𝑥 = 𝑢 ∧ 𝑦 = 𝑣) ∧ 𝜓)) → ∃𝑥∃𝑦((𝑥 = 𝑢 ∧ 𝑦 = 𝑣) ∧ (𝜑 ∧ 𝜓))) | 
| 58 | 20, 57 | impbii 209 | 1
⊢
(∃𝑥∃𝑦((𝑥 = 𝑢 ∧ 𝑦 = 𝑣) ∧ (𝜑 ∧ 𝜓)) ↔ (∃𝑥∃𝑦((𝑥 = 𝑢 ∧ 𝑦 = 𝑣) ∧ 𝜑) ∧ ∃𝑥∃𝑦((𝑥 = 𝑢 ∧ 𝑦 = 𝑣) ∧ 𝜓))) |