| Step | Hyp | Ref | Expression | 
|---|
| 1 |  | mgcval.2 | . . 3
⊢ (𝜑 → 𝑉 ∈ Proset ) | 
| 2 |  | mgccole.1 | . . . . . 6
⊢ (𝜑 → 𝐹𝐻𝐺) | 
| 3 |  | mgcoval.1 | . . . . . . 7
⊢ 𝐴 = (Base‘𝑉) | 
| 4 |  | mgcoval.2 | . . . . . . 7
⊢ 𝐵 = (Base‘𝑊) | 
| 5 |  | mgcoval.3 | . . . . . . 7
⊢  ≤ =
(le‘𝑉) | 
| 6 |  | mgcoval.4 | . . . . . . 7
⊢  ≲ =
(le‘𝑊) | 
| 7 |  | mgcval.1 | . . . . . . 7
⊢ 𝐻 = (𝑉MGalConn𝑊) | 
| 8 |  | mgcval.3 | . . . . . . 7
⊢ (𝜑 → 𝑊 ∈ Proset ) | 
| 9 | 3, 4, 5, 6, 7, 1, 8 | mgcval 32977 | . . . . . 6
⊢ (𝜑 → (𝐹𝐻𝐺 ↔ ((𝐹:𝐴⟶𝐵 ∧ 𝐺:𝐵⟶𝐴) ∧ ∀𝑥 ∈ 𝐴 ∀𝑦 ∈ 𝐵 ((𝐹‘𝑥) ≲ 𝑦 ↔ 𝑥 ≤ (𝐺‘𝑦))))) | 
| 10 | 2, 9 | mpbid 232 | . . . . 5
⊢ (𝜑 → ((𝐹:𝐴⟶𝐵 ∧ 𝐺:𝐵⟶𝐴) ∧ ∀𝑥 ∈ 𝐴 ∀𝑦 ∈ 𝐵 ((𝐹‘𝑥) ≲ 𝑦 ↔ 𝑥 ≤ (𝐺‘𝑦)))) | 
| 11 | 10 | simplrd 770 | . . . 4
⊢ (𝜑 → 𝐺:𝐵⟶𝐴) | 
| 12 |  | mgccole2.1 | . . . 4
⊢ (𝜑 → 𝑌 ∈ 𝐵) | 
| 13 | 11, 12 | ffvelcdmd 7105 | . . 3
⊢ (𝜑 → (𝐺‘𝑌) ∈ 𝐴) | 
| 14 | 3, 5 | prsref 18344 | . . 3
⊢ ((𝑉 ∈ Proset ∧ (𝐺‘𝑌) ∈ 𝐴) → (𝐺‘𝑌) ≤ (𝐺‘𝑌)) | 
| 15 | 1, 13, 14 | syl2anc 584 | . 2
⊢ (𝜑 → (𝐺‘𝑌) ≤ (𝐺‘𝑌)) | 
| 16 | 10 | simprd 495 | . . . 4
⊢ (𝜑 → ∀𝑥 ∈ 𝐴 ∀𝑦 ∈ 𝐵 ((𝐹‘𝑥) ≲ 𝑦 ↔ 𝑥 ≤ (𝐺‘𝑦))) | 
| 17 |  | fveq2 6906 | . . . . . . . . 9
⊢ (𝑥 = (𝐺‘𝑌) → (𝐹‘𝑥) = (𝐹‘(𝐺‘𝑌))) | 
| 18 | 17 | breq1d 5153 | . . . . . . . 8
⊢ (𝑥 = (𝐺‘𝑌) → ((𝐹‘𝑥) ≲ 𝑦 ↔ (𝐹‘(𝐺‘𝑌)) ≲ 𝑦)) | 
| 19 |  | breq1 5146 | . . . . . . . 8
⊢ (𝑥 = (𝐺‘𝑌) → (𝑥 ≤ (𝐺‘𝑦) ↔ (𝐺‘𝑌) ≤ (𝐺‘𝑦))) | 
| 20 | 18, 19 | bibi12d 345 | . . . . . . 7
⊢ (𝑥 = (𝐺‘𝑌) → (((𝐹‘𝑥) ≲ 𝑦 ↔ 𝑥 ≤ (𝐺‘𝑦)) ↔ ((𝐹‘(𝐺‘𝑌)) ≲ 𝑦 ↔ (𝐺‘𝑌) ≤ (𝐺‘𝑦)))) | 
| 21 | 20 | adantl 481 | . . . . . 6
⊢ ((𝜑 ∧ 𝑥 = (𝐺‘𝑌)) → (((𝐹‘𝑥) ≲ 𝑦 ↔ 𝑥 ≤ (𝐺‘𝑦)) ↔ ((𝐹‘(𝐺‘𝑌)) ≲ 𝑦 ↔ (𝐺‘𝑌) ≤ (𝐺‘𝑦)))) | 
| 22 | 21 | ralbidv 3178 | . . . . 5
⊢ ((𝜑 ∧ 𝑥 = (𝐺‘𝑌)) → (∀𝑦 ∈ 𝐵 ((𝐹‘𝑥) ≲ 𝑦 ↔ 𝑥 ≤ (𝐺‘𝑦)) ↔ ∀𝑦 ∈ 𝐵 ((𝐹‘(𝐺‘𝑌)) ≲ 𝑦 ↔ (𝐺‘𝑌) ≤ (𝐺‘𝑦)))) | 
| 23 | 13, 22 | rspcdv 3614 | . . . 4
⊢ (𝜑 → (∀𝑥 ∈ 𝐴 ∀𝑦 ∈ 𝐵 ((𝐹‘𝑥) ≲ 𝑦 ↔ 𝑥 ≤ (𝐺‘𝑦)) → ∀𝑦 ∈ 𝐵 ((𝐹‘(𝐺‘𝑌)) ≲ 𝑦 ↔ (𝐺‘𝑌) ≤ (𝐺‘𝑦)))) | 
| 24 | 16, 23 | mpd 15 | . . 3
⊢ (𝜑 → ∀𝑦 ∈ 𝐵 ((𝐹‘(𝐺‘𝑌)) ≲ 𝑦 ↔ (𝐺‘𝑌) ≤ (𝐺‘𝑦))) | 
| 25 |  | simpr 484 | . . . . . 6
⊢ ((𝜑 ∧ 𝑦 = 𝑌) → 𝑦 = 𝑌) | 
| 26 | 25 | breq2d 5155 | . . . . 5
⊢ ((𝜑 ∧ 𝑦 = 𝑌) → ((𝐹‘(𝐺‘𝑌)) ≲ 𝑦 ↔ (𝐹‘(𝐺‘𝑌)) ≲ 𝑌)) | 
| 27 |  | fveq2 6906 | . . . . . . 7
⊢ (𝑦 = 𝑌 → (𝐺‘𝑦) = (𝐺‘𝑌)) | 
| 28 | 27 | adantl 481 | . . . . . 6
⊢ ((𝜑 ∧ 𝑦 = 𝑌) → (𝐺‘𝑦) = (𝐺‘𝑌)) | 
| 29 | 28 | breq2d 5155 | . . . . 5
⊢ ((𝜑 ∧ 𝑦 = 𝑌) → ((𝐺‘𝑌) ≤ (𝐺‘𝑦) ↔ (𝐺‘𝑌) ≤ (𝐺‘𝑌))) | 
| 30 | 26, 29 | bibi12d 345 | . . . 4
⊢ ((𝜑 ∧ 𝑦 = 𝑌) → (((𝐹‘(𝐺‘𝑌)) ≲ 𝑦 ↔ (𝐺‘𝑌) ≤ (𝐺‘𝑦)) ↔ ((𝐹‘(𝐺‘𝑌)) ≲ 𝑌 ↔ (𝐺‘𝑌) ≤ (𝐺‘𝑌)))) | 
| 31 | 12, 30 | rspcdv 3614 | . . 3
⊢ (𝜑 → (∀𝑦 ∈ 𝐵 ((𝐹‘(𝐺‘𝑌)) ≲ 𝑦 ↔ (𝐺‘𝑌) ≤ (𝐺‘𝑦)) → ((𝐹‘(𝐺‘𝑌)) ≲ 𝑌 ↔ (𝐺‘𝑌) ≤ (𝐺‘𝑌)))) | 
| 32 | 24, 31 | mpd 15 | . 2
⊢ (𝜑 → ((𝐹‘(𝐺‘𝑌)) ≲ 𝑌 ↔ (𝐺‘𝑌) ≤ (𝐺‘𝑌))) | 
| 33 | 15, 32 | mpbird 257 | 1
⊢ (𝜑 → (𝐹‘(𝐺‘𝑌)) ≲ 𝑌) |