Theorem thincsect 46396

Description: In a thin category, one morphism is a section of another iff they are pointing towards each other. (Contributed by Zhi Wang, 24-Sep-2024.)

Hypotheses

Ref	Expression
thincsect.c	⊢ (𝜑 → 𝐶 ∈ ThinCat)
thincsect.b	⊢ 𝐵 = (Base‘𝐶)
thincsect.x	⊢ (𝜑 → 𝑋 ∈ 𝐵)
thincsect.y	⊢ (𝜑 → 𝑌 ∈ 𝐵)
thincsect.s	⊢ 𝑆 = (Sect‘𝐶)
thincsect.h	⊢ 𝐻 = (Hom ‘𝐶)

Assertion

Ref	Expression
thincsect	⊢ (𝜑 → (𝐹(𝑋𝑆𝑌)𝐺 ↔ (𝐹 ∈ (𝑋𝐻𝑌) ∧ 𝐺 ∈ (𝑌𝐻𝑋))))

Proof of Theorem thincsect

Step	Hyp	Ref	Expression
1		thincsect.b	. . . 4 ⊢ 𝐵 = (Base‘𝐶)
2		thincsect.h	. . . 4 ⊢ 𝐻 = (Hom ‘𝐶)
3		eqid 2736	. . . 4 ⊢ (comp‘𝐶) = (comp‘𝐶)
4		eqid 2736	. . . 4 ⊢ (Id‘𝐶) = (Id‘𝐶)
5		thincsect.s	. . . 4 ⊢ 𝑆 = (Sect‘𝐶)
6		thincsect.c	. . . . 5 ⊢ (𝜑 → 𝐶 ∈ ThinCat)
7	6	thinccd 46364	. . . 4 ⊢ (𝜑 → 𝐶 ∈ Cat)
8		thincsect.x	. . . 4 ⊢ (𝜑 → 𝑋 ∈ 𝐵)
9		thincsect.y	. . . 4 ⊢ (𝜑 → 𝑌 ∈ 𝐵)
10	1, 2, 3, 4, 5, 7, 8, 9	issect 17510	. . 3 ⊢ (𝜑 → (𝐹(𝑋𝑆𝑌)𝐺 ↔ (𝐹 ∈ (𝑋𝐻𝑌) ∧ 𝐺 ∈ (𝑌𝐻𝑋) ∧ (𝐺(⟨𝑋, 𝑌⟩(comp‘𝐶)𝑋)𝐹) = ((Id‘𝐶)‘𝑋))))
11		df-3an 1089	. . 3 ⊢ ((𝐹 ∈ (𝑋𝐻𝑌) ∧ 𝐺 ∈ (𝑌𝐻𝑋) ∧ (𝐺(⟨𝑋, 𝑌⟩(comp‘𝐶)𝑋)𝐹) = ((Id‘𝐶)‘𝑋)) ↔ ((𝐹 ∈ (𝑋𝐻𝑌) ∧ 𝐺 ∈ (𝑌𝐻𝑋)) ∧ (𝐺(⟨𝑋, 𝑌⟩(comp‘𝐶)𝑋)𝐹) = ((Id‘𝐶)‘𝑋)))
12	10, 11	bitrdi 287	. 2 ⊢ (𝜑 → (𝐹(𝑋𝑆𝑌)𝐺 ↔ ((𝐹 ∈ (𝑋𝐻𝑌) ∧ 𝐺 ∈ (𝑌𝐻𝑋)) ∧ (𝐺(⟨𝑋, 𝑌⟩(comp‘𝐶)𝑋)𝐹) = ((Id‘𝐶)‘𝑋))))
13	6	adantr 482	. . 3 ⊢ ((𝜑 ∧ (𝐹 ∈ (𝑋𝐻𝑌) ∧ 𝐺 ∈ (𝑌𝐻𝑋))) → 𝐶 ∈ ThinCat)
14	8	adantr 482	. . 3 ⊢ ((𝜑 ∧ (𝐹 ∈ (𝑋𝐻𝑌) ∧ 𝐺 ∈ (𝑌𝐻𝑋))) → 𝑋 ∈ 𝐵)
15	7	adantr 482	. . . 4 ⊢ ((𝜑 ∧ (𝐹 ∈ (𝑋𝐻𝑌) ∧ 𝐺 ∈ (𝑌𝐻𝑋))) → 𝐶 ∈ Cat)
16	9	adantr 482	. . . 4 ⊢ ((𝜑 ∧ (𝐹 ∈ (𝑋𝐻𝑌) ∧ 𝐺 ∈ (𝑌𝐻𝑋))) → 𝑌 ∈ 𝐵)
17		simprl 769	. . . 4 ⊢ ((𝜑 ∧ (𝐹 ∈ (𝑋𝐻𝑌) ∧ 𝐺 ∈ (𝑌𝐻𝑋))) → 𝐹 ∈ (𝑋𝐻𝑌))
18		simprr 771	. . . 4 ⊢ ((𝜑 ∧ (𝐹 ∈ (𝑋𝐻𝑌) ∧ 𝐺 ∈ (𝑌𝐻𝑋))) → 𝐺 ∈ (𝑌𝐻𝑋))
19	1, 2, 3, 15, 14, 16, 14, 17, 18	catcocl 17439	. . 3 ⊢ ((𝜑 ∧ (𝐹 ∈ (𝑋𝐻𝑌) ∧ 𝐺 ∈ (𝑌𝐻𝑋))) → (𝐺(⟨𝑋, 𝑌⟩(comp‘𝐶)𝑋)𝐹) ∈ (𝑋𝐻𝑋))
20	13, 1, 2, 14, 4, 19	thincid 46372	. 2 ⊢ ((𝜑 ∧ (𝐹 ∈ (𝑋𝐻𝑌) ∧ 𝐺 ∈ (𝑌𝐻𝑋))) → (𝐺(⟨𝑋, 𝑌⟩(comp‘𝐶)𝑋)𝐹) = ((Id‘𝐶)‘𝑋))
21	12, 20	mpbiran3d 46200	1 ⊢ (𝜑 → (𝐹(𝑋𝑆𝑌)𝐺 ↔ (𝐹 ∈ (𝑋𝐻𝑌) ∧ 𝐺 ∈ (𝑌𝐻𝑋))))

Syntax hints:   → wi 4   ↔ wb 205   ∧ wa 397   ∧ w3a 1087   = wceq 1539   ∈ wcel 2104  ⟨cop 4571   class class class wbr 5081  ‘cfv 6458  (class class class)co 7307  Basecbs 16957  Hom chom 17018  compcco 17019  Catccat 17418  Idccid 17419  Sectcsect 17501  ThinCatcthinc 46358

This theorem was proved from axioms:  ax-mp 5  ax-1 6  ax-2 7  ax-3 8  ax-gen 1795  ax-4 1809  ax-5 1911  ax-6 1969  ax-7 2009  ax-8 2106  ax-9 2114  ax-10 2135  ax-11 2152  ax-12 2169  ax-ext 2707  ax-rep 5218  ax-sep 5232  ax-nul 5239  ax-pow 5297  ax-pr 5361  ax-un 7620

This theorem depends on definitions:  df-bi 206  df-an 398  df-or 846  df-3an 1089  df-tru 1542  df-fal 1552  df-ex 1780  df-nf 1784  df-sb 2066  df-mo 2538  df-eu 2567  df-clab 2714  df-cleq 2728  df-clel 2814  df-nfc 2887  df-ne 2942  df-ral 3063  df-rex 3072  df-rmo 3285  df-reu 3286  df-rab 3287  df-v 3439  df-sbc 3722  df-csb 3838  df-dif 3895  df-un 3897  df-in 3899  df-ss 3909  df-nul 4263  df-if 4466  df-pw 4541  df-sn 4566  df-pr 4568  df-op 4572  df-uni 4845  df-iun 4933  df-br 5082  df-opab 5144  df-mpt 5165  df-id 5500  df-xp 5606  df-rel 5607  df-cnv 5608  df-co 5609  df-dm 5610  df-rn 5611  df-res 5612  df-ima 5613  df-iota 6410  df-fun 6460  df-fn 6461  df-f 6462  df-f1 6463  df-fo 6464  df-f1o 6465  df-fv 6466  df-riota 7264  df-ov 7310  df-oprab 7311  df-mpo 7312  df-1st 7863  df-2nd 7864  df-cat 17422  df-cid 17423  df-sect 17504  df-thinc 46359

This theorem is referenced by:  thincsect2  46397  thinciso  46399