| Step | Hyp | Ref
 | Expression | 
| 1 |   | f1oiso2.1 | 
. . 3
⊢ 𝑆 = {〈𝑥, 𝑦〉 ∣ ((𝑥 ∈ 𝐵 ∧ 𝑦 ∈ 𝐵) ∧ (◡𝐻‘𝑥)𝑅(◡𝐻‘𝑦))} | 
| 2 |   | f1ocnvdm 5828 | 
. . . . . . . . 9
⊢ ((𝐻:𝐴–1-1-onto→𝐵 ∧ 𝑥 ∈ 𝐵) → (◡𝐻‘𝑥) ∈ 𝐴) | 
| 3 | 2 | adantrr 479 | 
. . . . . . . 8
⊢ ((𝐻:𝐴–1-1-onto→𝐵 ∧ (𝑥 ∈ 𝐵 ∧ 𝑦 ∈ 𝐵)) → (◡𝐻‘𝑥) ∈ 𝐴) | 
| 4 | 3 | 3adant3 1019 | 
. . . . . . 7
⊢ ((𝐻:𝐴–1-1-onto→𝐵 ∧ (𝑥 ∈ 𝐵 ∧ 𝑦 ∈ 𝐵) ∧ (◡𝐻‘𝑥)𝑅(◡𝐻‘𝑦)) → (◡𝐻‘𝑥) ∈ 𝐴) | 
| 5 |   | f1ocnvdm 5828 | 
. . . . . . . . . 10
⊢ ((𝐻:𝐴–1-1-onto→𝐵 ∧ 𝑦 ∈ 𝐵) → (◡𝐻‘𝑦) ∈ 𝐴) | 
| 6 | 5 | adantrl 478 | 
. . . . . . . . 9
⊢ ((𝐻:𝐴–1-1-onto→𝐵 ∧ (𝑥 ∈ 𝐵 ∧ 𝑦 ∈ 𝐵)) → (◡𝐻‘𝑦) ∈ 𝐴) | 
| 7 | 6 | 3adant3 1019 | 
. . . . . . . 8
⊢ ((𝐻:𝐴–1-1-onto→𝐵 ∧ (𝑥 ∈ 𝐵 ∧ 𝑦 ∈ 𝐵) ∧ (◡𝐻‘𝑥)𝑅(◡𝐻‘𝑦)) → (◡𝐻‘𝑦) ∈ 𝐴) | 
| 8 |   | f1ocnvfv2 5825 | 
. . . . . . . . . . 11
⊢ ((𝐻:𝐴–1-1-onto→𝐵 ∧ 𝑥 ∈ 𝐵) → (𝐻‘(◡𝐻‘𝑥)) = 𝑥) | 
| 9 | 8 | eqcomd 2202 | 
. . . . . . . . . 10
⊢ ((𝐻:𝐴–1-1-onto→𝐵 ∧ 𝑥 ∈ 𝐵) → 𝑥 = (𝐻‘(◡𝐻‘𝑥))) | 
| 10 |   | f1ocnvfv2 5825 | 
. . . . . . . . . . 11
⊢ ((𝐻:𝐴–1-1-onto→𝐵 ∧ 𝑦 ∈ 𝐵) → (𝐻‘(◡𝐻‘𝑦)) = 𝑦) | 
| 11 | 10 | eqcomd 2202 | 
. . . . . . . . . 10
⊢ ((𝐻:𝐴–1-1-onto→𝐵 ∧ 𝑦 ∈ 𝐵) → 𝑦 = (𝐻‘(◡𝐻‘𝑦))) | 
| 12 | 9, 11 | anim12dan 600 | 
. . . . . . . . 9
⊢ ((𝐻:𝐴–1-1-onto→𝐵 ∧ (𝑥 ∈ 𝐵 ∧ 𝑦 ∈ 𝐵)) → (𝑥 = (𝐻‘(◡𝐻‘𝑥)) ∧ 𝑦 = (𝐻‘(◡𝐻‘𝑦)))) | 
| 13 | 12 | 3adant3 1019 | 
. . . . . . . 8
⊢ ((𝐻:𝐴–1-1-onto→𝐵 ∧ (𝑥 ∈ 𝐵 ∧ 𝑦 ∈ 𝐵) ∧ (◡𝐻‘𝑥)𝑅(◡𝐻‘𝑦)) → (𝑥 = (𝐻‘(◡𝐻‘𝑥)) ∧ 𝑦 = (𝐻‘(◡𝐻‘𝑦)))) | 
| 14 |   | simp3 1001 | 
. . . . . . . 8
⊢ ((𝐻:𝐴–1-1-onto→𝐵 ∧ (𝑥 ∈ 𝐵 ∧ 𝑦 ∈ 𝐵) ∧ (◡𝐻‘𝑥)𝑅(◡𝐻‘𝑦)) → (◡𝐻‘𝑥)𝑅(◡𝐻‘𝑦)) | 
| 15 |   | fveq2 5558 | 
. . . . . . . . . . . 12
⊢ (𝑤 = (◡𝐻‘𝑦) → (𝐻‘𝑤) = (𝐻‘(◡𝐻‘𝑦))) | 
| 16 | 15 | eqeq2d 2208 | 
. . . . . . . . . . 11
⊢ (𝑤 = (◡𝐻‘𝑦) → (𝑦 = (𝐻‘𝑤) ↔ 𝑦 = (𝐻‘(◡𝐻‘𝑦)))) | 
| 17 | 16 | anbi2d 464 | 
. . . . . . . . . 10
⊢ (𝑤 = (◡𝐻‘𝑦) → ((𝑥 = (𝐻‘(◡𝐻‘𝑥)) ∧ 𝑦 = (𝐻‘𝑤)) ↔ (𝑥 = (𝐻‘(◡𝐻‘𝑥)) ∧ 𝑦 = (𝐻‘(◡𝐻‘𝑦))))) | 
| 18 |   | breq2 4037 | 
. . . . . . . . . 10
⊢ (𝑤 = (◡𝐻‘𝑦) → ((◡𝐻‘𝑥)𝑅𝑤 ↔ (◡𝐻‘𝑥)𝑅(◡𝐻‘𝑦))) | 
| 19 | 17, 18 | anbi12d 473 | 
. . . . . . . . 9
⊢ (𝑤 = (◡𝐻‘𝑦) → (((𝑥 = (𝐻‘(◡𝐻‘𝑥)) ∧ 𝑦 = (𝐻‘𝑤)) ∧ (◡𝐻‘𝑥)𝑅𝑤) ↔ ((𝑥 = (𝐻‘(◡𝐻‘𝑥)) ∧ 𝑦 = (𝐻‘(◡𝐻‘𝑦))) ∧ (◡𝐻‘𝑥)𝑅(◡𝐻‘𝑦)))) | 
| 20 | 19 | rspcev 2868 | 
. . . . . . . 8
⊢ (((◡𝐻‘𝑦) ∈ 𝐴 ∧ ((𝑥 = (𝐻‘(◡𝐻‘𝑥)) ∧ 𝑦 = (𝐻‘(◡𝐻‘𝑦))) ∧ (◡𝐻‘𝑥)𝑅(◡𝐻‘𝑦))) → ∃𝑤 ∈ 𝐴 ((𝑥 = (𝐻‘(◡𝐻‘𝑥)) ∧ 𝑦 = (𝐻‘𝑤)) ∧ (◡𝐻‘𝑥)𝑅𝑤)) | 
| 21 | 7, 13, 14, 20 | syl12anc 1247 | 
. . . . . . 7
⊢ ((𝐻:𝐴–1-1-onto→𝐵 ∧ (𝑥 ∈ 𝐵 ∧ 𝑦 ∈ 𝐵) ∧ (◡𝐻‘𝑥)𝑅(◡𝐻‘𝑦)) → ∃𝑤 ∈ 𝐴 ((𝑥 = (𝐻‘(◡𝐻‘𝑥)) ∧ 𝑦 = (𝐻‘𝑤)) ∧ (◡𝐻‘𝑥)𝑅𝑤)) | 
| 22 |   | fveq2 5558 | 
. . . . . . . . . . . 12
⊢ (𝑧 = (◡𝐻‘𝑥) → (𝐻‘𝑧) = (𝐻‘(◡𝐻‘𝑥))) | 
| 23 | 22 | eqeq2d 2208 | 
. . . . . . . . . . 11
⊢ (𝑧 = (◡𝐻‘𝑥) → (𝑥 = (𝐻‘𝑧) ↔ 𝑥 = (𝐻‘(◡𝐻‘𝑥)))) | 
| 24 | 23 | anbi1d 465 | 
. . . . . . . . . 10
⊢ (𝑧 = (◡𝐻‘𝑥) → ((𝑥 = (𝐻‘𝑧) ∧ 𝑦 = (𝐻‘𝑤)) ↔ (𝑥 = (𝐻‘(◡𝐻‘𝑥)) ∧ 𝑦 = (𝐻‘𝑤)))) | 
| 25 |   | breq1 4036 | 
. . . . . . . . . 10
⊢ (𝑧 = (◡𝐻‘𝑥) → (𝑧𝑅𝑤 ↔ (◡𝐻‘𝑥)𝑅𝑤)) | 
| 26 | 24, 25 | anbi12d 473 | 
. . . . . . . . 9
⊢ (𝑧 = (◡𝐻‘𝑥) → (((𝑥 = (𝐻‘𝑧) ∧ 𝑦 = (𝐻‘𝑤)) ∧ 𝑧𝑅𝑤) ↔ ((𝑥 = (𝐻‘(◡𝐻‘𝑥)) ∧ 𝑦 = (𝐻‘𝑤)) ∧ (◡𝐻‘𝑥)𝑅𝑤))) | 
| 27 | 26 | rexbidv 2498 | 
. . . . . . . 8
⊢ (𝑧 = (◡𝐻‘𝑥) → (∃𝑤 ∈ 𝐴 ((𝑥 = (𝐻‘𝑧) ∧ 𝑦 = (𝐻‘𝑤)) ∧ 𝑧𝑅𝑤) ↔ ∃𝑤 ∈ 𝐴 ((𝑥 = (𝐻‘(◡𝐻‘𝑥)) ∧ 𝑦 = (𝐻‘𝑤)) ∧ (◡𝐻‘𝑥)𝑅𝑤))) | 
| 28 | 27 | rspcev 2868 | 
. . . . . . 7
⊢ (((◡𝐻‘𝑥) ∈ 𝐴 ∧ ∃𝑤 ∈ 𝐴 ((𝑥 = (𝐻‘(◡𝐻‘𝑥)) ∧ 𝑦 = (𝐻‘𝑤)) ∧ (◡𝐻‘𝑥)𝑅𝑤)) → ∃𝑧 ∈ 𝐴 ∃𝑤 ∈ 𝐴 ((𝑥 = (𝐻‘𝑧) ∧ 𝑦 = (𝐻‘𝑤)) ∧ 𝑧𝑅𝑤)) | 
| 29 | 4, 21, 28 | syl2anc 411 | 
. . . . . 6
⊢ ((𝐻:𝐴–1-1-onto→𝐵 ∧ (𝑥 ∈ 𝐵 ∧ 𝑦 ∈ 𝐵) ∧ (◡𝐻‘𝑥)𝑅(◡𝐻‘𝑦)) → ∃𝑧 ∈ 𝐴 ∃𝑤 ∈ 𝐴 ((𝑥 = (𝐻‘𝑧) ∧ 𝑦 = (𝐻‘𝑤)) ∧ 𝑧𝑅𝑤)) | 
| 30 | 29 | 3expib 1208 | 
. . . . 5
⊢ (𝐻:𝐴–1-1-onto→𝐵 → (((𝑥 ∈ 𝐵 ∧ 𝑦 ∈ 𝐵) ∧ (◡𝐻‘𝑥)𝑅(◡𝐻‘𝑦)) → ∃𝑧 ∈ 𝐴 ∃𝑤 ∈ 𝐴 ((𝑥 = (𝐻‘𝑧) ∧ 𝑦 = (𝐻‘𝑤)) ∧ 𝑧𝑅𝑤))) | 
| 31 |   | simp3ll 1070 | 
. . . . . . . . 9
⊢ ((𝐻:𝐴–1-1-onto→𝐵 ∧ (𝑧 ∈ 𝐴 ∧ 𝑤 ∈ 𝐴) ∧ ((𝑥 = (𝐻‘𝑧) ∧ 𝑦 = (𝐻‘𝑤)) ∧ 𝑧𝑅𝑤)) → 𝑥 = (𝐻‘𝑧)) | 
| 32 |   | simp1 999 | 
. . . . . . . . . 10
⊢ ((𝐻:𝐴–1-1-onto→𝐵 ∧ (𝑧 ∈ 𝐴 ∧ 𝑤 ∈ 𝐴) ∧ ((𝑥 = (𝐻‘𝑧) ∧ 𝑦 = (𝐻‘𝑤)) ∧ 𝑧𝑅𝑤)) → 𝐻:𝐴–1-1-onto→𝐵) | 
| 33 |   | simp2l 1025 | 
. . . . . . . . . 10
⊢ ((𝐻:𝐴–1-1-onto→𝐵 ∧ (𝑧 ∈ 𝐴 ∧ 𝑤 ∈ 𝐴) ∧ ((𝑥 = (𝐻‘𝑧) ∧ 𝑦 = (𝐻‘𝑤)) ∧ 𝑧𝑅𝑤)) → 𝑧 ∈ 𝐴) | 
| 34 |   | f1of 5504 | 
. . . . . . . . . . 11
⊢ (𝐻:𝐴–1-1-onto→𝐵 → 𝐻:𝐴⟶𝐵) | 
| 35 | 34 | ffvelcdmda 5697 | 
. . . . . . . . . 10
⊢ ((𝐻:𝐴–1-1-onto→𝐵 ∧ 𝑧 ∈ 𝐴) → (𝐻‘𝑧) ∈ 𝐵) | 
| 36 | 32, 33, 35 | syl2anc 411 | 
. . . . . . . . 9
⊢ ((𝐻:𝐴–1-1-onto→𝐵 ∧ (𝑧 ∈ 𝐴 ∧ 𝑤 ∈ 𝐴) ∧ ((𝑥 = (𝐻‘𝑧) ∧ 𝑦 = (𝐻‘𝑤)) ∧ 𝑧𝑅𝑤)) → (𝐻‘𝑧) ∈ 𝐵) | 
| 37 | 31, 36 | eqeltrd 2273 | 
. . . . . . . 8
⊢ ((𝐻:𝐴–1-1-onto→𝐵 ∧ (𝑧 ∈ 𝐴 ∧ 𝑤 ∈ 𝐴) ∧ ((𝑥 = (𝐻‘𝑧) ∧ 𝑦 = (𝐻‘𝑤)) ∧ 𝑧𝑅𝑤)) → 𝑥 ∈ 𝐵) | 
| 38 |   | simp3lr 1071 | 
. . . . . . . . 9
⊢ ((𝐻:𝐴–1-1-onto→𝐵 ∧ (𝑧 ∈ 𝐴 ∧ 𝑤 ∈ 𝐴) ∧ ((𝑥 = (𝐻‘𝑧) ∧ 𝑦 = (𝐻‘𝑤)) ∧ 𝑧𝑅𝑤)) → 𝑦 = (𝐻‘𝑤)) | 
| 39 |   | simp2r 1026 | 
. . . . . . . . . 10
⊢ ((𝐻:𝐴–1-1-onto→𝐵 ∧ (𝑧 ∈ 𝐴 ∧ 𝑤 ∈ 𝐴) ∧ ((𝑥 = (𝐻‘𝑧) ∧ 𝑦 = (𝐻‘𝑤)) ∧ 𝑧𝑅𝑤)) → 𝑤 ∈ 𝐴) | 
| 40 | 34 | ffvelcdmda 5697 | 
. . . . . . . . . 10
⊢ ((𝐻:𝐴–1-1-onto→𝐵 ∧ 𝑤 ∈ 𝐴) → (𝐻‘𝑤) ∈ 𝐵) | 
| 41 | 32, 39, 40 | syl2anc 411 | 
. . . . . . . . 9
⊢ ((𝐻:𝐴–1-1-onto→𝐵 ∧ (𝑧 ∈ 𝐴 ∧ 𝑤 ∈ 𝐴) ∧ ((𝑥 = (𝐻‘𝑧) ∧ 𝑦 = (𝐻‘𝑤)) ∧ 𝑧𝑅𝑤)) → (𝐻‘𝑤) ∈ 𝐵) | 
| 42 | 38, 41 | eqeltrd 2273 | 
. . . . . . . 8
⊢ ((𝐻:𝐴–1-1-onto→𝐵 ∧ (𝑧 ∈ 𝐴 ∧ 𝑤 ∈ 𝐴) ∧ ((𝑥 = (𝐻‘𝑧) ∧ 𝑦 = (𝐻‘𝑤)) ∧ 𝑧𝑅𝑤)) → 𝑦 ∈ 𝐵) | 
| 43 |   | simp3r 1028 | 
. . . . . . . . 9
⊢ ((𝐻:𝐴–1-1-onto→𝐵 ∧ (𝑧 ∈ 𝐴 ∧ 𝑤 ∈ 𝐴) ∧ ((𝑥 = (𝐻‘𝑧) ∧ 𝑦 = (𝐻‘𝑤)) ∧ 𝑧𝑅𝑤)) → 𝑧𝑅𝑤) | 
| 44 | 31 | eqcomd 2202 | 
. . . . . . . . . 10
⊢ ((𝐻:𝐴–1-1-onto→𝐵 ∧ (𝑧 ∈ 𝐴 ∧ 𝑤 ∈ 𝐴) ∧ ((𝑥 = (𝐻‘𝑧) ∧ 𝑦 = (𝐻‘𝑤)) ∧ 𝑧𝑅𝑤)) → (𝐻‘𝑧) = 𝑥) | 
| 45 |   | f1ocnvfv 5826 | 
. . . . . . . . . . 11
⊢ ((𝐻:𝐴–1-1-onto→𝐵 ∧ 𝑧 ∈ 𝐴) → ((𝐻‘𝑧) = 𝑥 → (◡𝐻‘𝑥) = 𝑧)) | 
| 46 | 32, 33, 45 | syl2anc 411 | 
. . . . . . . . . 10
⊢ ((𝐻:𝐴–1-1-onto→𝐵 ∧ (𝑧 ∈ 𝐴 ∧ 𝑤 ∈ 𝐴) ∧ ((𝑥 = (𝐻‘𝑧) ∧ 𝑦 = (𝐻‘𝑤)) ∧ 𝑧𝑅𝑤)) → ((𝐻‘𝑧) = 𝑥 → (◡𝐻‘𝑥) = 𝑧)) | 
| 47 | 44, 46 | mpd 13 | 
. . . . . . . . 9
⊢ ((𝐻:𝐴–1-1-onto→𝐵 ∧ (𝑧 ∈ 𝐴 ∧ 𝑤 ∈ 𝐴) ∧ ((𝑥 = (𝐻‘𝑧) ∧ 𝑦 = (𝐻‘𝑤)) ∧ 𝑧𝑅𝑤)) → (◡𝐻‘𝑥) = 𝑧) | 
| 48 | 38 | eqcomd 2202 | 
. . . . . . . . . 10
⊢ ((𝐻:𝐴–1-1-onto→𝐵 ∧ (𝑧 ∈ 𝐴 ∧ 𝑤 ∈ 𝐴) ∧ ((𝑥 = (𝐻‘𝑧) ∧ 𝑦 = (𝐻‘𝑤)) ∧ 𝑧𝑅𝑤)) → (𝐻‘𝑤) = 𝑦) | 
| 49 |   | f1ocnvfv 5826 | 
. . . . . . . . . . 11
⊢ ((𝐻:𝐴–1-1-onto→𝐵 ∧ 𝑤 ∈ 𝐴) → ((𝐻‘𝑤) = 𝑦 → (◡𝐻‘𝑦) = 𝑤)) | 
| 50 | 32, 39, 49 | syl2anc 411 | 
. . . . . . . . . 10
⊢ ((𝐻:𝐴–1-1-onto→𝐵 ∧ (𝑧 ∈ 𝐴 ∧ 𝑤 ∈ 𝐴) ∧ ((𝑥 = (𝐻‘𝑧) ∧ 𝑦 = (𝐻‘𝑤)) ∧ 𝑧𝑅𝑤)) → ((𝐻‘𝑤) = 𝑦 → (◡𝐻‘𝑦) = 𝑤)) | 
| 51 | 48, 50 | mpd 13 | 
. . . . . . . . 9
⊢ ((𝐻:𝐴–1-1-onto→𝐵 ∧ (𝑧 ∈ 𝐴 ∧ 𝑤 ∈ 𝐴) ∧ ((𝑥 = (𝐻‘𝑧) ∧ 𝑦 = (𝐻‘𝑤)) ∧ 𝑧𝑅𝑤)) → (◡𝐻‘𝑦) = 𝑤) | 
| 52 | 43, 47, 51 | 3brtr4d 4065 | 
. . . . . . . 8
⊢ ((𝐻:𝐴–1-1-onto→𝐵 ∧ (𝑧 ∈ 𝐴 ∧ 𝑤 ∈ 𝐴) ∧ ((𝑥 = (𝐻‘𝑧) ∧ 𝑦 = (𝐻‘𝑤)) ∧ 𝑧𝑅𝑤)) → (◡𝐻‘𝑥)𝑅(◡𝐻‘𝑦)) | 
| 53 | 37, 42, 52 | jca31 309 | 
. . . . . . 7
⊢ ((𝐻:𝐴–1-1-onto→𝐵 ∧ (𝑧 ∈ 𝐴 ∧ 𝑤 ∈ 𝐴) ∧ ((𝑥 = (𝐻‘𝑧) ∧ 𝑦 = (𝐻‘𝑤)) ∧ 𝑧𝑅𝑤)) → ((𝑥 ∈ 𝐵 ∧ 𝑦 ∈ 𝐵) ∧ (◡𝐻‘𝑥)𝑅(◡𝐻‘𝑦))) | 
| 54 | 53 | 3exp 1204 | 
. . . . . 6
⊢ (𝐻:𝐴–1-1-onto→𝐵 → ((𝑧 ∈ 𝐴 ∧ 𝑤 ∈ 𝐴) → (((𝑥 = (𝐻‘𝑧) ∧ 𝑦 = (𝐻‘𝑤)) ∧ 𝑧𝑅𝑤) → ((𝑥 ∈ 𝐵 ∧ 𝑦 ∈ 𝐵) ∧ (◡𝐻‘𝑥)𝑅(◡𝐻‘𝑦))))) | 
| 55 | 54 | rexlimdvv 2621 | 
. . . . 5
⊢ (𝐻:𝐴–1-1-onto→𝐵 → (∃𝑧 ∈ 𝐴 ∃𝑤 ∈ 𝐴 ((𝑥 = (𝐻‘𝑧) ∧ 𝑦 = (𝐻‘𝑤)) ∧ 𝑧𝑅𝑤) → ((𝑥 ∈ 𝐵 ∧ 𝑦 ∈ 𝐵) ∧ (◡𝐻‘𝑥)𝑅(◡𝐻‘𝑦)))) | 
| 56 | 30, 55 | impbid 129 | 
. . . 4
⊢ (𝐻:𝐴–1-1-onto→𝐵 → (((𝑥 ∈ 𝐵 ∧ 𝑦 ∈ 𝐵) ∧ (◡𝐻‘𝑥)𝑅(◡𝐻‘𝑦)) ↔ ∃𝑧 ∈ 𝐴 ∃𝑤 ∈ 𝐴 ((𝑥 = (𝐻‘𝑧) ∧ 𝑦 = (𝐻‘𝑤)) ∧ 𝑧𝑅𝑤))) | 
| 57 | 56 | opabbidv 4099 | 
. . 3
⊢ (𝐻:𝐴–1-1-onto→𝐵 → {〈𝑥, 𝑦〉 ∣ ((𝑥 ∈ 𝐵 ∧ 𝑦 ∈ 𝐵) ∧ (◡𝐻‘𝑥)𝑅(◡𝐻‘𝑦))} = {〈𝑥, 𝑦〉 ∣ ∃𝑧 ∈ 𝐴 ∃𝑤 ∈ 𝐴 ((𝑥 = (𝐻‘𝑧) ∧ 𝑦 = (𝐻‘𝑤)) ∧ 𝑧𝑅𝑤)}) | 
| 58 | 1, 57 | eqtrid 2241 | 
. 2
⊢ (𝐻:𝐴–1-1-onto→𝐵 → 𝑆 = {〈𝑥, 𝑦〉 ∣ ∃𝑧 ∈ 𝐴 ∃𝑤 ∈ 𝐴 ((𝑥 = (𝐻‘𝑧) ∧ 𝑦 = (𝐻‘𝑤)) ∧ 𝑧𝑅𝑤)}) | 
| 59 |   | f1oiso 5873 | 
. 2
⊢ ((𝐻:𝐴–1-1-onto→𝐵 ∧ 𝑆 = {〈𝑥, 𝑦〉 ∣ ∃𝑧 ∈ 𝐴 ∃𝑤 ∈ 𝐴 ((𝑥 = (𝐻‘𝑧) ∧ 𝑦 = (𝐻‘𝑤)) ∧ 𝑧𝑅𝑤)}) → 𝐻 Isom 𝑅, 𝑆 (𝐴, 𝐵)) | 
| 60 | 58, 59 | mpdan 421 | 
1
⊢ (𝐻:𝐴–1-1-onto→𝐵 → 𝐻 Isom 𝑅, 𝑆 (𝐴, 𝐵)) |