Step | Hyp | Ref
| Expression |
1 | | isof1o 7174 |
. . . . . . . . . . 11
⊢ (𝐻 Isom 𝑅, 𝑆 (𝐴, 𝐵) → 𝐻:𝐴–1-1-onto→𝐵) |
2 | | f1of 6700 |
. . . . . . . . . . 11
⊢ (𝐻:𝐴–1-1-onto→𝐵 → 𝐻:𝐴⟶𝐵) |
3 | | ffvelrn 6941 |
. . . . . . . . . . . . 13
⊢ ((𝐻:𝐴⟶𝐵 ∧ 𝑑 ∈ 𝐴) → (𝐻‘𝑑) ∈ 𝐵) |
4 | 3 | ex 412 |
. . . . . . . . . . . 12
⊢ (𝐻:𝐴⟶𝐵 → (𝑑 ∈ 𝐴 → (𝐻‘𝑑) ∈ 𝐵)) |
5 | | ffvelrn 6941 |
. . . . . . . . . . . . 13
⊢ ((𝐻:𝐴⟶𝐵 ∧ 𝑒 ∈ 𝐴) → (𝐻‘𝑒) ∈ 𝐵) |
6 | 5 | ex 412 |
. . . . . . . . . . . 12
⊢ (𝐻:𝐴⟶𝐵 → (𝑒 ∈ 𝐴 → (𝐻‘𝑒) ∈ 𝐵)) |
7 | | ffvelrn 6941 |
. . . . . . . . . . . . 13
⊢ ((𝐻:𝐴⟶𝐵 ∧ 𝑓 ∈ 𝐴) → (𝐻‘𝑓) ∈ 𝐵) |
8 | 7 | ex 412 |
. . . . . . . . . . . 12
⊢ (𝐻:𝐴⟶𝐵 → (𝑓 ∈ 𝐴 → (𝐻‘𝑓) ∈ 𝐵)) |
9 | 4, 6, 8 | 3anim123d 1441 |
. . . . . . . . . . 11
⊢ (𝐻:𝐴⟶𝐵 → ((𝑑 ∈ 𝐴 ∧ 𝑒 ∈ 𝐴 ∧ 𝑓 ∈ 𝐴) → ((𝐻‘𝑑) ∈ 𝐵 ∧ (𝐻‘𝑒) ∈ 𝐵 ∧ (𝐻‘𝑓) ∈ 𝐵))) |
10 | 1, 2, 9 | 3syl 18 |
. . . . . . . . . 10
⊢ (𝐻 Isom 𝑅, 𝑆 (𝐴, 𝐵) → ((𝑑 ∈ 𝐴 ∧ 𝑒 ∈ 𝐴 ∧ 𝑓 ∈ 𝐴) → ((𝐻‘𝑑) ∈ 𝐵 ∧ (𝐻‘𝑒) ∈ 𝐵 ∧ (𝐻‘𝑓) ∈ 𝐵))) |
11 | 10 | imp 406 |
. . . . . . . . 9
⊢ ((𝐻 Isom 𝑅, 𝑆 (𝐴, 𝐵) ∧ (𝑑 ∈ 𝐴 ∧ 𝑒 ∈ 𝐴 ∧ 𝑓 ∈ 𝐴)) → ((𝐻‘𝑑) ∈ 𝐵 ∧ (𝐻‘𝑒) ∈ 𝐵 ∧ (𝐻‘𝑓) ∈ 𝐵)) |
12 | | breq12 5075 |
. . . . . . . . . . . . 13
⊢ ((𝑎 = (𝐻‘𝑑) ∧ 𝑎 = (𝐻‘𝑑)) → (𝑎𝑆𝑎 ↔ (𝐻‘𝑑)𝑆(𝐻‘𝑑))) |
13 | 12 | anidms 566 |
. . . . . . . . . . . 12
⊢ (𝑎 = (𝐻‘𝑑) → (𝑎𝑆𝑎 ↔ (𝐻‘𝑑)𝑆(𝐻‘𝑑))) |
14 | 13 | notbid 317 |
. . . . . . . . . . 11
⊢ (𝑎 = (𝐻‘𝑑) → (¬ 𝑎𝑆𝑎 ↔ ¬ (𝐻‘𝑑)𝑆(𝐻‘𝑑))) |
15 | | breq1 5073 |
. . . . . . . . . . . . 13
⊢ (𝑎 = (𝐻‘𝑑) → (𝑎𝑆𝑏 ↔ (𝐻‘𝑑)𝑆𝑏)) |
16 | 15 | anbi1d 629 |
. . . . . . . . . . . 12
⊢ (𝑎 = (𝐻‘𝑑) → ((𝑎𝑆𝑏 ∧ 𝑏𝑆𝑐) ↔ ((𝐻‘𝑑)𝑆𝑏 ∧ 𝑏𝑆𝑐))) |
17 | | breq1 5073 |
. . . . . . . . . . . 12
⊢ (𝑎 = (𝐻‘𝑑) → (𝑎𝑆𝑐 ↔ (𝐻‘𝑑)𝑆𝑐)) |
18 | 16, 17 | imbi12d 344 |
. . . . . . . . . . 11
⊢ (𝑎 = (𝐻‘𝑑) → (((𝑎𝑆𝑏 ∧ 𝑏𝑆𝑐) → 𝑎𝑆𝑐) ↔ (((𝐻‘𝑑)𝑆𝑏 ∧ 𝑏𝑆𝑐) → (𝐻‘𝑑)𝑆𝑐))) |
19 | 14, 18 | anbi12d 630 |
. . . . . . . . . 10
⊢ (𝑎 = (𝐻‘𝑑) → ((¬ 𝑎𝑆𝑎 ∧ ((𝑎𝑆𝑏 ∧ 𝑏𝑆𝑐) → 𝑎𝑆𝑐)) ↔ (¬ (𝐻‘𝑑)𝑆(𝐻‘𝑑) ∧ (((𝐻‘𝑑)𝑆𝑏 ∧ 𝑏𝑆𝑐) → (𝐻‘𝑑)𝑆𝑐)))) |
20 | | breq2 5074 |
. . . . . . . . . . . . 13
⊢ (𝑏 = (𝐻‘𝑒) → ((𝐻‘𝑑)𝑆𝑏 ↔ (𝐻‘𝑑)𝑆(𝐻‘𝑒))) |
21 | | breq1 5073 |
. . . . . . . . . . . . 13
⊢ (𝑏 = (𝐻‘𝑒) → (𝑏𝑆𝑐 ↔ (𝐻‘𝑒)𝑆𝑐)) |
22 | 20, 21 | anbi12d 630 |
. . . . . . . . . . . 12
⊢ (𝑏 = (𝐻‘𝑒) → (((𝐻‘𝑑)𝑆𝑏 ∧ 𝑏𝑆𝑐) ↔ ((𝐻‘𝑑)𝑆(𝐻‘𝑒) ∧ (𝐻‘𝑒)𝑆𝑐))) |
23 | 22 | imbi1d 341 |
. . . . . . . . . . 11
⊢ (𝑏 = (𝐻‘𝑒) → ((((𝐻‘𝑑)𝑆𝑏 ∧ 𝑏𝑆𝑐) → (𝐻‘𝑑)𝑆𝑐) ↔ (((𝐻‘𝑑)𝑆(𝐻‘𝑒) ∧ (𝐻‘𝑒)𝑆𝑐) → (𝐻‘𝑑)𝑆𝑐))) |
24 | 23 | anbi2d 628 |
. . . . . . . . . 10
⊢ (𝑏 = (𝐻‘𝑒) → ((¬ (𝐻‘𝑑)𝑆(𝐻‘𝑑) ∧ (((𝐻‘𝑑)𝑆𝑏 ∧ 𝑏𝑆𝑐) → (𝐻‘𝑑)𝑆𝑐)) ↔ (¬ (𝐻‘𝑑)𝑆(𝐻‘𝑑) ∧ (((𝐻‘𝑑)𝑆(𝐻‘𝑒) ∧ (𝐻‘𝑒)𝑆𝑐) → (𝐻‘𝑑)𝑆𝑐)))) |
25 | | breq2 5074 |
. . . . . . . . . . . . 13
⊢ (𝑐 = (𝐻‘𝑓) → ((𝐻‘𝑒)𝑆𝑐 ↔ (𝐻‘𝑒)𝑆(𝐻‘𝑓))) |
26 | 25 | anbi2d 628 |
. . . . . . . . . . . 12
⊢ (𝑐 = (𝐻‘𝑓) → (((𝐻‘𝑑)𝑆(𝐻‘𝑒) ∧ (𝐻‘𝑒)𝑆𝑐) ↔ ((𝐻‘𝑑)𝑆(𝐻‘𝑒) ∧ (𝐻‘𝑒)𝑆(𝐻‘𝑓)))) |
27 | | breq2 5074 |
. . . . . . . . . . . 12
⊢ (𝑐 = (𝐻‘𝑓) → ((𝐻‘𝑑)𝑆𝑐 ↔ (𝐻‘𝑑)𝑆(𝐻‘𝑓))) |
28 | 26, 27 | imbi12d 344 |
. . . . . . . . . . 11
⊢ (𝑐 = (𝐻‘𝑓) → ((((𝐻‘𝑑)𝑆(𝐻‘𝑒) ∧ (𝐻‘𝑒)𝑆𝑐) → (𝐻‘𝑑)𝑆𝑐) ↔ (((𝐻‘𝑑)𝑆(𝐻‘𝑒) ∧ (𝐻‘𝑒)𝑆(𝐻‘𝑓)) → (𝐻‘𝑑)𝑆(𝐻‘𝑓)))) |
29 | 28 | anbi2d 628 |
. . . . . . . . . 10
⊢ (𝑐 = (𝐻‘𝑓) → ((¬ (𝐻‘𝑑)𝑆(𝐻‘𝑑) ∧ (((𝐻‘𝑑)𝑆(𝐻‘𝑒) ∧ (𝐻‘𝑒)𝑆𝑐) → (𝐻‘𝑑)𝑆𝑐)) ↔ (¬ (𝐻‘𝑑)𝑆(𝐻‘𝑑) ∧ (((𝐻‘𝑑)𝑆(𝐻‘𝑒) ∧ (𝐻‘𝑒)𝑆(𝐻‘𝑓)) → (𝐻‘𝑑)𝑆(𝐻‘𝑓))))) |
30 | 19, 24, 29 | rspc3v 3565 |
. . . . . . . . 9
⊢ (((𝐻‘𝑑) ∈ 𝐵 ∧ (𝐻‘𝑒) ∈ 𝐵 ∧ (𝐻‘𝑓) ∈ 𝐵) → (∀𝑎 ∈ 𝐵 ∀𝑏 ∈ 𝐵 ∀𝑐 ∈ 𝐵 (¬ 𝑎𝑆𝑎 ∧ ((𝑎𝑆𝑏 ∧ 𝑏𝑆𝑐) → 𝑎𝑆𝑐)) → (¬ (𝐻‘𝑑)𝑆(𝐻‘𝑑) ∧ (((𝐻‘𝑑)𝑆(𝐻‘𝑒) ∧ (𝐻‘𝑒)𝑆(𝐻‘𝑓)) → (𝐻‘𝑑)𝑆(𝐻‘𝑓))))) |
31 | 11, 30 | syl 17 |
. . . . . . . 8
⊢ ((𝐻 Isom 𝑅, 𝑆 (𝐴, 𝐵) ∧ (𝑑 ∈ 𝐴 ∧ 𝑒 ∈ 𝐴 ∧ 𝑓 ∈ 𝐴)) → (∀𝑎 ∈ 𝐵 ∀𝑏 ∈ 𝐵 ∀𝑐 ∈ 𝐵 (¬ 𝑎𝑆𝑎 ∧ ((𝑎𝑆𝑏 ∧ 𝑏𝑆𝑐) → 𝑎𝑆𝑐)) → (¬ (𝐻‘𝑑)𝑆(𝐻‘𝑑) ∧ (((𝐻‘𝑑)𝑆(𝐻‘𝑒) ∧ (𝐻‘𝑒)𝑆(𝐻‘𝑓)) → (𝐻‘𝑑)𝑆(𝐻‘𝑓))))) |
32 | | simpl 482 |
. . . . . . . . . . 11
⊢ ((𝐻 Isom 𝑅, 𝑆 (𝐴, 𝐵) ∧ (𝑑 ∈ 𝐴 ∧ 𝑒 ∈ 𝐴 ∧ 𝑓 ∈ 𝐴)) → 𝐻 Isom 𝑅, 𝑆 (𝐴, 𝐵)) |
33 | | simpr1 1192 |
. . . . . . . . . . 11
⊢ ((𝐻 Isom 𝑅, 𝑆 (𝐴, 𝐵) ∧ (𝑑 ∈ 𝐴 ∧ 𝑒 ∈ 𝐴 ∧ 𝑓 ∈ 𝐴)) → 𝑑 ∈ 𝐴) |
34 | | isorel 7177 |
. . . . . . . . . . 11
⊢ ((𝐻 Isom 𝑅, 𝑆 (𝐴, 𝐵) ∧ (𝑑 ∈ 𝐴 ∧ 𝑑 ∈ 𝐴)) → (𝑑𝑅𝑑 ↔ (𝐻‘𝑑)𝑆(𝐻‘𝑑))) |
35 | 32, 33, 33, 34 | syl12anc 833 |
. . . . . . . . . 10
⊢ ((𝐻 Isom 𝑅, 𝑆 (𝐴, 𝐵) ∧ (𝑑 ∈ 𝐴 ∧ 𝑒 ∈ 𝐴 ∧ 𝑓 ∈ 𝐴)) → (𝑑𝑅𝑑 ↔ (𝐻‘𝑑)𝑆(𝐻‘𝑑))) |
36 | 35 | notbid 317 |
. . . . . . . . 9
⊢ ((𝐻 Isom 𝑅, 𝑆 (𝐴, 𝐵) ∧ (𝑑 ∈ 𝐴 ∧ 𝑒 ∈ 𝐴 ∧ 𝑓 ∈ 𝐴)) → (¬ 𝑑𝑅𝑑 ↔ ¬ (𝐻‘𝑑)𝑆(𝐻‘𝑑))) |
37 | | simpr2 1193 |
. . . . . . . . . . . 12
⊢ ((𝐻 Isom 𝑅, 𝑆 (𝐴, 𝐵) ∧ (𝑑 ∈ 𝐴 ∧ 𝑒 ∈ 𝐴 ∧ 𝑓 ∈ 𝐴)) → 𝑒 ∈ 𝐴) |
38 | | isorel 7177 |
. . . . . . . . . . . 12
⊢ ((𝐻 Isom 𝑅, 𝑆 (𝐴, 𝐵) ∧ (𝑑 ∈ 𝐴 ∧ 𝑒 ∈ 𝐴)) → (𝑑𝑅𝑒 ↔ (𝐻‘𝑑)𝑆(𝐻‘𝑒))) |
39 | 32, 33, 37, 38 | syl12anc 833 |
. . . . . . . . . . 11
⊢ ((𝐻 Isom 𝑅, 𝑆 (𝐴, 𝐵) ∧ (𝑑 ∈ 𝐴 ∧ 𝑒 ∈ 𝐴 ∧ 𝑓 ∈ 𝐴)) → (𝑑𝑅𝑒 ↔ (𝐻‘𝑑)𝑆(𝐻‘𝑒))) |
40 | | simpr3 1194 |
. . . . . . . . . . . 12
⊢ ((𝐻 Isom 𝑅, 𝑆 (𝐴, 𝐵) ∧ (𝑑 ∈ 𝐴 ∧ 𝑒 ∈ 𝐴 ∧ 𝑓 ∈ 𝐴)) → 𝑓 ∈ 𝐴) |
41 | | isorel 7177 |
. . . . . . . . . . . 12
⊢ ((𝐻 Isom 𝑅, 𝑆 (𝐴, 𝐵) ∧ (𝑒 ∈ 𝐴 ∧ 𝑓 ∈ 𝐴)) → (𝑒𝑅𝑓 ↔ (𝐻‘𝑒)𝑆(𝐻‘𝑓))) |
42 | 32, 37, 40, 41 | syl12anc 833 |
. . . . . . . . . . 11
⊢ ((𝐻 Isom 𝑅, 𝑆 (𝐴, 𝐵) ∧ (𝑑 ∈ 𝐴 ∧ 𝑒 ∈ 𝐴 ∧ 𝑓 ∈ 𝐴)) → (𝑒𝑅𝑓 ↔ (𝐻‘𝑒)𝑆(𝐻‘𝑓))) |
43 | 39, 42 | anbi12d 630 |
. . . . . . . . . 10
⊢ ((𝐻 Isom 𝑅, 𝑆 (𝐴, 𝐵) ∧ (𝑑 ∈ 𝐴 ∧ 𝑒 ∈ 𝐴 ∧ 𝑓 ∈ 𝐴)) → ((𝑑𝑅𝑒 ∧ 𝑒𝑅𝑓) ↔ ((𝐻‘𝑑)𝑆(𝐻‘𝑒) ∧ (𝐻‘𝑒)𝑆(𝐻‘𝑓)))) |
44 | | isorel 7177 |
. . . . . . . . . . 11
⊢ ((𝐻 Isom 𝑅, 𝑆 (𝐴, 𝐵) ∧ (𝑑 ∈ 𝐴 ∧ 𝑓 ∈ 𝐴)) → (𝑑𝑅𝑓 ↔ (𝐻‘𝑑)𝑆(𝐻‘𝑓))) |
45 | 32, 33, 40, 44 | syl12anc 833 |
. . . . . . . . . 10
⊢ ((𝐻 Isom 𝑅, 𝑆 (𝐴, 𝐵) ∧ (𝑑 ∈ 𝐴 ∧ 𝑒 ∈ 𝐴 ∧ 𝑓 ∈ 𝐴)) → (𝑑𝑅𝑓 ↔ (𝐻‘𝑑)𝑆(𝐻‘𝑓))) |
46 | 43, 45 | imbi12d 344 |
. . . . . . . . 9
⊢ ((𝐻 Isom 𝑅, 𝑆 (𝐴, 𝐵) ∧ (𝑑 ∈ 𝐴 ∧ 𝑒 ∈ 𝐴 ∧ 𝑓 ∈ 𝐴)) → (((𝑑𝑅𝑒 ∧ 𝑒𝑅𝑓) → 𝑑𝑅𝑓) ↔ (((𝐻‘𝑑)𝑆(𝐻‘𝑒) ∧ (𝐻‘𝑒)𝑆(𝐻‘𝑓)) → (𝐻‘𝑑)𝑆(𝐻‘𝑓)))) |
47 | 36, 46 | anbi12d 630 |
. . . . . . . 8
⊢ ((𝐻 Isom 𝑅, 𝑆 (𝐴, 𝐵) ∧ (𝑑 ∈ 𝐴 ∧ 𝑒 ∈ 𝐴 ∧ 𝑓 ∈ 𝐴)) → ((¬ 𝑑𝑅𝑑 ∧ ((𝑑𝑅𝑒 ∧ 𝑒𝑅𝑓) → 𝑑𝑅𝑓)) ↔ (¬ (𝐻‘𝑑)𝑆(𝐻‘𝑑) ∧ (((𝐻‘𝑑)𝑆(𝐻‘𝑒) ∧ (𝐻‘𝑒)𝑆(𝐻‘𝑓)) → (𝐻‘𝑑)𝑆(𝐻‘𝑓))))) |
48 | 31, 47 | sylibrd 258 |
. . . . . . 7
⊢ ((𝐻 Isom 𝑅, 𝑆 (𝐴, 𝐵) ∧ (𝑑 ∈ 𝐴 ∧ 𝑒 ∈ 𝐴 ∧ 𝑓 ∈ 𝐴)) → (∀𝑎 ∈ 𝐵 ∀𝑏 ∈ 𝐵 ∀𝑐 ∈ 𝐵 (¬ 𝑎𝑆𝑎 ∧ ((𝑎𝑆𝑏 ∧ 𝑏𝑆𝑐) → 𝑎𝑆𝑐)) → (¬ 𝑑𝑅𝑑 ∧ ((𝑑𝑅𝑒 ∧ 𝑒𝑅𝑓) → 𝑑𝑅𝑓)))) |
49 | 48 | ex 412 |
. . . . . 6
⊢ (𝐻 Isom 𝑅, 𝑆 (𝐴, 𝐵) → ((𝑑 ∈ 𝐴 ∧ 𝑒 ∈ 𝐴 ∧ 𝑓 ∈ 𝐴) → (∀𝑎 ∈ 𝐵 ∀𝑏 ∈ 𝐵 ∀𝑐 ∈ 𝐵 (¬ 𝑎𝑆𝑎 ∧ ((𝑎𝑆𝑏 ∧ 𝑏𝑆𝑐) → 𝑎𝑆𝑐)) → (¬ 𝑑𝑅𝑑 ∧ ((𝑑𝑅𝑒 ∧ 𝑒𝑅𝑓) → 𝑑𝑅𝑓))))) |
50 | 49 | com23 86 |
. . . . 5
⊢ (𝐻 Isom 𝑅, 𝑆 (𝐴, 𝐵) → (∀𝑎 ∈ 𝐵 ∀𝑏 ∈ 𝐵 ∀𝑐 ∈ 𝐵 (¬ 𝑎𝑆𝑎 ∧ ((𝑎𝑆𝑏 ∧ 𝑏𝑆𝑐) → 𝑎𝑆𝑐)) → ((𝑑 ∈ 𝐴 ∧ 𝑒 ∈ 𝐴 ∧ 𝑓 ∈ 𝐴) → (¬ 𝑑𝑅𝑑 ∧ ((𝑑𝑅𝑒 ∧ 𝑒𝑅𝑓) → 𝑑𝑅𝑓))))) |
51 | 50 | imp31 417 |
. . . 4
⊢ (((𝐻 Isom 𝑅, 𝑆 (𝐴, 𝐵) ∧ ∀𝑎 ∈ 𝐵 ∀𝑏 ∈ 𝐵 ∀𝑐 ∈ 𝐵 (¬ 𝑎𝑆𝑎 ∧ ((𝑎𝑆𝑏 ∧ 𝑏𝑆𝑐) → 𝑎𝑆𝑐))) ∧ (𝑑 ∈ 𝐴 ∧ 𝑒 ∈ 𝐴 ∧ 𝑓 ∈ 𝐴)) → (¬ 𝑑𝑅𝑑 ∧ ((𝑑𝑅𝑒 ∧ 𝑒𝑅𝑓) → 𝑑𝑅𝑓))) |
52 | 51 | ralrimivvva 3115 |
. . 3
⊢ ((𝐻 Isom 𝑅, 𝑆 (𝐴, 𝐵) ∧ ∀𝑎 ∈ 𝐵 ∀𝑏 ∈ 𝐵 ∀𝑐 ∈ 𝐵 (¬ 𝑎𝑆𝑎 ∧ ((𝑎𝑆𝑏 ∧ 𝑏𝑆𝑐) → 𝑎𝑆𝑐))) → ∀𝑑 ∈ 𝐴 ∀𝑒 ∈ 𝐴 ∀𝑓 ∈ 𝐴 (¬ 𝑑𝑅𝑑 ∧ ((𝑑𝑅𝑒 ∧ 𝑒𝑅𝑓) → 𝑑𝑅𝑓))) |
53 | 52 | ex 412 |
. 2
⊢ (𝐻 Isom 𝑅, 𝑆 (𝐴, 𝐵) → (∀𝑎 ∈ 𝐵 ∀𝑏 ∈ 𝐵 ∀𝑐 ∈ 𝐵 (¬ 𝑎𝑆𝑎 ∧ ((𝑎𝑆𝑏 ∧ 𝑏𝑆𝑐) → 𝑎𝑆𝑐)) → ∀𝑑 ∈ 𝐴 ∀𝑒 ∈ 𝐴 ∀𝑓 ∈ 𝐴 (¬ 𝑑𝑅𝑑 ∧ ((𝑑𝑅𝑒 ∧ 𝑒𝑅𝑓) → 𝑑𝑅𝑓)))) |
54 | | df-po 5494 |
. 2
⊢ (𝑆 Po 𝐵 ↔ ∀𝑎 ∈ 𝐵 ∀𝑏 ∈ 𝐵 ∀𝑐 ∈ 𝐵 (¬ 𝑎𝑆𝑎 ∧ ((𝑎𝑆𝑏 ∧ 𝑏𝑆𝑐) → 𝑎𝑆𝑐))) |
55 | | df-po 5494 |
. 2
⊢ (𝑅 Po 𝐴 ↔ ∀𝑑 ∈ 𝐴 ∀𝑒 ∈ 𝐴 ∀𝑓 ∈ 𝐴 (¬ 𝑑𝑅𝑑 ∧ ((𝑑𝑅𝑒 ∧ 𝑒𝑅𝑓) → 𝑑𝑅𝑓))) |
56 | 53, 54, 55 | 3imtr4g 295 |
1
⊢ (𝐻 Isom 𝑅, 𝑆 (𝐴, 𝐵) → (𝑆 Po 𝐵 → 𝑅 Po 𝐴)) |