Proof of Theorem cgsex4g
| Step | Hyp | Ref | Expression | 
|---|
| 1 |  | cgsex4g.2 | . . . . 5
⊢ (𝜒 → (𝜑 ↔ 𝜓)) | 
| 2 | 1 | biimpa 476 | . . . 4
⊢ ((𝜒 ∧ 𝜑) → 𝜓) | 
| 3 | 2 | exlimivv 1931 | . . 3
⊢
(∃𝑧∃𝑤(𝜒 ∧ 𝜑) → 𝜓) | 
| 4 | 3 | exlimivv 1931 | . 2
⊢
(∃𝑥∃𝑦∃𝑧∃𝑤(𝜒 ∧ 𝜑) → 𝜓) | 
| 5 |  | elisset 2822 | . . . . . . 7
⊢ (𝐴 ∈ 𝑅 → ∃𝑥 𝑥 = 𝐴) | 
| 6 |  | elisset 2822 | . . . . . . 7
⊢ (𝐵 ∈ 𝑆 → ∃𝑦 𝑦 = 𝐵) | 
| 7 | 5, 6 | anim12i 613 | . . . . . 6
⊢ ((𝐴 ∈ 𝑅 ∧ 𝐵 ∈ 𝑆) → (∃𝑥 𝑥 = 𝐴 ∧ ∃𝑦 𝑦 = 𝐵)) | 
| 8 |  | elisset 2822 | . . . . . . 7
⊢ (𝐶 ∈ 𝑅 → ∃𝑧 𝑧 = 𝐶) | 
| 9 |  | elisset 2822 | . . . . . . 7
⊢ (𝐷 ∈ 𝑆 → ∃𝑤 𝑤 = 𝐷) | 
| 10 | 8, 9 | anim12i 613 | . . . . . 6
⊢ ((𝐶 ∈ 𝑅 ∧ 𝐷 ∈ 𝑆) → (∃𝑧 𝑧 = 𝐶 ∧ ∃𝑤 𝑤 = 𝐷)) | 
| 11 | 7, 10 | anim12i 613 | . . . . 5
⊢ (((𝐴 ∈ 𝑅 ∧ 𝐵 ∈ 𝑆) ∧ (𝐶 ∈ 𝑅 ∧ 𝐷 ∈ 𝑆)) → ((∃𝑥 𝑥 = 𝐴 ∧ ∃𝑦 𝑦 = 𝐵) ∧ (∃𝑧 𝑧 = 𝐶 ∧ ∃𝑤 𝑤 = 𝐷))) | 
| 12 |  | 19.42vv 1956 | . . . . . . 7
⊢
(∃𝑧∃𝑤((𝑥 = 𝐴 ∧ 𝑦 = 𝐵) ∧ (𝑧 = 𝐶 ∧ 𝑤 = 𝐷)) ↔ ((𝑥 = 𝐴 ∧ 𝑦 = 𝐵) ∧ ∃𝑧∃𝑤(𝑧 = 𝐶 ∧ 𝑤 = 𝐷))) | 
| 13 | 12 | 2exbii 1848 | . . . . . 6
⊢
(∃𝑥∃𝑦∃𝑧∃𝑤((𝑥 = 𝐴 ∧ 𝑦 = 𝐵) ∧ (𝑧 = 𝐶 ∧ 𝑤 = 𝐷)) ↔ ∃𝑥∃𝑦((𝑥 = 𝐴 ∧ 𝑦 = 𝐵) ∧ ∃𝑧∃𝑤(𝑧 = 𝐶 ∧ 𝑤 = 𝐷))) | 
| 14 |  | 19.41vv 1949 | . . . . . 6
⊢
(∃𝑥∃𝑦((𝑥 = 𝐴 ∧ 𝑦 = 𝐵) ∧ ∃𝑧∃𝑤(𝑧 = 𝐶 ∧ 𝑤 = 𝐷)) ↔ (∃𝑥∃𝑦(𝑥 = 𝐴 ∧ 𝑦 = 𝐵) ∧ ∃𝑧∃𝑤(𝑧 = 𝐶 ∧ 𝑤 = 𝐷))) | 
| 15 |  | exdistrv 1954 | . . . . . . 7
⊢
(∃𝑥∃𝑦(𝑥 = 𝐴 ∧ 𝑦 = 𝐵) ↔ (∃𝑥 𝑥 = 𝐴 ∧ ∃𝑦 𝑦 = 𝐵)) | 
| 16 |  | exdistrv 1954 | . . . . . . 7
⊢
(∃𝑧∃𝑤(𝑧 = 𝐶 ∧ 𝑤 = 𝐷) ↔ (∃𝑧 𝑧 = 𝐶 ∧ ∃𝑤 𝑤 = 𝐷)) | 
| 17 | 15, 16 | anbi12i 628 | . . . . . 6
⊢
((∃𝑥∃𝑦(𝑥 = 𝐴 ∧ 𝑦 = 𝐵) ∧ ∃𝑧∃𝑤(𝑧 = 𝐶 ∧ 𝑤 = 𝐷)) ↔ ((∃𝑥 𝑥 = 𝐴 ∧ ∃𝑦 𝑦 = 𝐵) ∧ (∃𝑧 𝑧 = 𝐶 ∧ ∃𝑤 𝑤 = 𝐷))) | 
| 18 | 13, 14, 17 | 3bitri 297 | . . . . 5
⊢
(∃𝑥∃𝑦∃𝑧∃𝑤((𝑥 = 𝐴 ∧ 𝑦 = 𝐵) ∧ (𝑧 = 𝐶 ∧ 𝑤 = 𝐷)) ↔ ((∃𝑥 𝑥 = 𝐴 ∧ ∃𝑦 𝑦 = 𝐵) ∧ (∃𝑧 𝑧 = 𝐶 ∧ ∃𝑤 𝑤 = 𝐷))) | 
| 19 | 11, 18 | sylibr 234 | . . . 4
⊢ (((𝐴 ∈ 𝑅 ∧ 𝐵 ∈ 𝑆) ∧ (𝐶 ∈ 𝑅 ∧ 𝐷 ∈ 𝑆)) → ∃𝑥∃𝑦∃𝑧∃𝑤((𝑥 = 𝐴 ∧ 𝑦 = 𝐵) ∧ (𝑧 = 𝐶 ∧ 𝑤 = 𝐷))) | 
| 20 |  | cgsex4g.1 | . . . . . 6
⊢ (((𝑥 = 𝐴 ∧ 𝑦 = 𝐵) ∧ (𝑧 = 𝐶 ∧ 𝑤 = 𝐷)) → 𝜒) | 
| 21 | 20 | 2eximi 1835 | . . . . 5
⊢
(∃𝑧∃𝑤((𝑥 = 𝐴 ∧ 𝑦 = 𝐵) ∧ (𝑧 = 𝐶 ∧ 𝑤 = 𝐷)) → ∃𝑧∃𝑤𝜒) | 
| 22 | 21 | 2eximi 1835 | . . . 4
⊢
(∃𝑥∃𝑦∃𝑧∃𝑤((𝑥 = 𝐴 ∧ 𝑦 = 𝐵) ∧ (𝑧 = 𝐶 ∧ 𝑤 = 𝐷)) → ∃𝑥∃𝑦∃𝑧∃𝑤𝜒) | 
| 23 | 19, 22 | syl 17 | . . 3
⊢ (((𝐴 ∈ 𝑅 ∧ 𝐵 ∈ 𝑆) ∧ (𝐶 ∈ 𝑅 ∧ 𝐷 ∈ 𝑆)) → ∃𝑥∃𝑦∃𝑧∃𝑤𝜒) | 
| 24 | 1 | biimprcd 250 | . . . . . 6
⊢ (𝜓 → (𝜒 → 𝜑)) | 
| 25 | 24 | ancld 550 | . . . . 5
⊢ (𝜓 → (𝜒 → (𝜒 ∧ 𝜑))) | 
| 26 | 25 | 2eximdv 1918 | . . . 4
⊢ (𝜓 → (∃𝑧∃𝑤𝜒 → ∃𝑧∃𝑤(𝜒 ∧ 𝜑))) | 
| 27 | 26 | 2eximdv 1918 | . . 3
⊢ (𝜓 → (∃𝑥∃𝑦∃𝑧∃𝑤𝜒 → ∃𝑥∃𝑦∃𝑧∃𝑤(𝜒 ∧ 𝜑))) | 
| 28 | 23, 27 | syl5com 31 | . 2
⊢ (((𝐴 ∈ 𝑅 ∧ 𝐵 ∈ 𝑆) ∧ (𝐶 ∈ 𝑅 ∧ 𝐷 ∈ 𝑆)) → (𝜓 → ∃𝑥∃𝑦∃𝑧∃𝑤(𝜒 ∧ 𝜑))) | 
| 29 | 4, 28 | impbid2 226 | 1
⊢ (((𝐴 ∈ 𝑅 ∧ 𝐵 ∈ 𝑆) ∧ (𝐶 ∈ 𝑅 ∧ 𝐷 ∈ 𝑆)) → (∃𝑥∃𝑦∃𝑧∃𝑤(𝜒 ∧ 𝜑) ↔ 𝜓)) |