Theorem fulltermc2 50349

Description: Given a full functor to a terminal category, the source category must not have empty hom-sets. (Contributed by Zhi Wang, 17-Oct-2025.) (Proof shortened by Zhi Wang, 6-Nov-2025.)

Hypotheses

Ref	Expression
fulltermc.b	⊢ 𝐵 = (Base‘𝐶)
fulltermc.h	⊢ 𝐻 = (Hom ‘𝐶)
fulltermc.d	⊢ (𝜑 → 𝐷 ∈ TermCat)
fulltermc2.f	⊢ (𝜑 → 𝐹(𝐶 Full 𝐷)𝐺)
fulltermc2.x	⊢ (𝜑 → 𝑋 ∈ 𝐵)
fulltermc2.y	⊢ (𝜑 → 𝑌 ∈ 𝐵)

Assertion

Ref	Expression
fulltermc2	⊢ (𝜑 → ¬ (𝑋𝐻𝑌) = ∅)

Proof of Theorem fulltermc2

Dummy variables 𝑥 𝑦 are mutually distinct and distinct from all other variables.

Step	Hyp	Ref	Expression
1		oveq1 7426	. . . 4 ⊢ (𝑥 = 𝑋 → (𝑥𝐻𝑦) = (𝑋𝐻𝑦))
2	1	eqeq1d 2767	. . 3 ⊢ (𝑥 = 𝑋 → ((𝑥𝐻𝑦) = ∅ ↔ (𝑋𝐻𝑦) = ∅))
3	2	notbid 321	. 2 ⊢ (𝑥 = 𝑋 → (¬ (𝑥𝐻𝑦) = ∅ ↔ ¬ (𝑋𝐻𝑦) = ∅))
4		oveq2 7427	. . . 4 ⊢ (𝑦 = 𝑌 → (𝑋𝐻𝑦) = (𝑋𝐻𝑌))
5	4	eqeq1d 2767	. . 3 ⊢ (𝑦 = 𝑌 → ((𝑋𝐻𝑦) = ∅ ↔ (𝑋𝐻𝑌) = ∅))
6	5	notbid 321	. 2 ⊢ (𝑦 = 𝑌 → (¬ (𝑋𝐻𝑦) = ∅ ↔ ¬ (𝑋𝐻𝑌) = ∅))
7		fulltermc2.f	. . 3 ⊢ (𝜑 → 𝐹(𝐶 Full 𝐷)𝐺)
8		fulltermc.b	. . . 4 ⊢ 𝐵 = (Base‘𝐶)
9		fulltermc.h	. . . 4 ⊢ 𝐻 = (Hom ‘𝐶)
10		fulltermc.d	. . . 4 ⊢ (𝜑 → 𝐷 ∈ TermCat)
11		fullfunc 17989	. . . . . 6 ⊢ (𝐶 Full 𝐷) ⊆ (𝐶 Func 𝐷)
12	11	ssbri 5158	. . . . 5 ⊢ (𝐹(𝐶 Full 𝐷)𝐺 → 𝐹(𝐶 Func 𝐷)𝐺)
13	7, 12	syl 18	. . . 4 ⊢ (𝜑 → 𝐹(𝐶 Func 𝐷)𝐺)
14	8, 9, 10, 13	fulltermc 50348	. . 3 ⊢ (𝜑 → (𝐹(𝐶 Full 𝐷)𝐺 ↔ ∀𝑥 ∈ 𝐵 ∀𝑦 ∈ 𝐵 ¬ (𝑥𝐻𝑦) = ∅))
15	7, 14	mpbid 235	. 2 ⊢ (𝜑 → ∀𝑥 ∈ 𝐵 ∀𝑦 ∈ 𝐵 ¬ (𝑥𝐻𝑦) = ∅)
16		fulltermc2.x	. 2 ⊢ (𝜑 → 𝑋 ∈ 𝐵)
17		fulltermc2.y	. 2 ⊢ (𝜑 → 𝑌 ∈ 𝐵)
18	3, 6, 15, 16, 17	rspc2dv 3598	1 ⊢ (𝜑 → ¬ (𝑋𝐻𝑌) = ∅)

This proof depends on syntax axioms:  ¬ wn 3   → wi 4   = wceq 1570   ∈ wcel 2146  ∀wral 3081  ∅c0 4286   class class class wbr 5111  ‘cfv 6540  (class class class)co 7419  Basecbs 17293  Hom chom 17345   Func cfunc 17935   Full cful 17985  TermCatctermc 50309

This proof depends on axioms:  ax-mp 5  ax-1 6  ax-2 7  ax-3 8  ax-gen 1828  ax-4 1842  ax-5 1943  ax-6 2000  ax-7 2041  ax-8 2148  ax-9 2156  ax-10 2179  ax-11 2195  ax-12 2216  ax-ext 2737  ax-rep 5240  ax-sep 5259  ax-nul 5271  ax-pow 5338  ax-pr 5406  ax-un 7742

This proof depends on definitions:  df-bi 210  df-an 402  df-or 862  df-3an 1105  df-tru 1573  df-fal 1583  df-ex 1813  df-nf 1817  df-sb 2100  df-mo 2569  df-eu 2599  df-clab 2744  df-cleq 2757  df-clel 2840  df-nfc 2914  df-ne 2961  df-ral 3082  df-rex 3092  df-rmo 3371  df-reu 3372  df-rab 3419  df-v 3459  df-sbc 3747  df-csb 3855  df-dif 3909  df-un 3911  df-in 3913  df-ss 3923  df-nul 4287  df-if 4490  df-pw 4566  df-sn 4592  df-pr 4594  df-op 4598  df-uni 4875  df-iun 4960  df-br 5112  df-opab 5176  df-mpt 5195  df-id 5558  df-xp 5669  df-rel 5670  df-cnv 5671  df-co 5672  df-dm 5673  df-rn 5674  df-res 5675  df-ima 5676  df-iota 6496  df-fun 6542  df-fn 6543  df-f 6544  df-f1 6545  df-fo 6546  df-f1o 6547  df-fv 6548  df-riota 7376  df-ov 7422  df-oprab 7423  df-mpo 7424  df-1st 7992  df-2nd 7993  df-map 8832  df-ixp 8902  df-cat 17748  df-cid 17749  df-func 17939  df-full 17987  df-thinc 50255  df-termc 50310

This theorem is used by: (None)