Theorem fulltermc 50322

Description: A functor to a terminal category is full iff all hom-sets of the source category are non-empty. (Contributed by Zhi Wang, 17-Oct-2025.)

Hypotheses

Ref	Expression
fulltermc.b	⊢ 𝐵 = (Base‘𝐶)
fulltermc.h	⊢ 𝐻 = (Hom ‘𝐶)
fulltermc.d	⊢ (𝜑 → 𝐷 ∈ TermCat)
fulltermc.f	⊢ (𝜑 → 𝐹(𝐶 Func 𝐷)𝐺)

Assertion

Ref	Expression
fulltermc	⊢ (𝜑 → (𝐹(𝐶 Full 𝐷)𝐺 ↔ ∀𝑥 ∈ 𝐵 ∀𝑦 ∈ 𝐵 ¬ (𝑥𝐻𝑦) = ∅))

Distinct variable groups:   𝑥,𝐵,𝑦   𝑥,𝐶,𝑦   𝑥,𝐷,𝑦   𝑥,𝐹,𝑦   𝑥,𝐺,𝑦   𝑥,𝐻,𝑦   𝜑,𝑥,𝑦

Proof of Theorem fulltermc

Step	Hyp	Ref	Expression
1		fulltermc.b	. . 3 ⊢ 𝐵 = (Base‘𝐶)
2		eqid 2765	. . 3 ⊢ (Hom ‘𝐷) = (Hom ‘𝐷)
3		fulltermc.h	. . 3 ⊢ 𝐻 = (Hom ‘𝐶)
4		fulltermc.d	. . . 4 ⊢ (𝜑 → 𝐷 ∈ TermCat)
5	4	termcthind 50289	. . 3 ⊢ (𝜑 → 𝐷 ∈ ThinCat)
6		fulltermc.f	. . 3 ⊢ (𝜑 → 𝐹(𝐶 Func 𝐷)𝐺)
7	1, 2, 3, 5, 6	fullthinc 50261	. 2 ⊢ (𝜑 → (𝐹(𝐶 Full 𝐷)𝐺 ↔ ∀𝑥 ∈ 𝐵 ∀𝑦 ∈ 𝐵 ((𝑥𝐻𝑦) = ∅ → ((𝐹‘𝑥)(Hom ‘𝐷)(𝐹‘𝑦)) = ∅)))
8	4	adantr 486	. . . . . 6 ⊢ ((𝜑 ∧ (𝑥 ∈ 𝐵 ∧ 𝑦 ∈ 𝐵)) → 𝐷 ∈ TermCat)
9		eqid 2765	. . . . . 6 ⊢ (Base‘𝐷) = (Base‘𝐷)
10	1, 9, 6	funcf1 17941	. . . . . . . 8 ⊢ (𝜑 → 𝐹:𝐵⟶(Base‘𝐷))
11	10	ffvelcdmda 7083	. . . . . . 7 ⊢ ((𝜑 ∧ 𝑥 ∈ 𝐵) → (𝐹‘𝑥) ∈ (Base‘𝐷))
12	11	adantrr 730	. . . . . 6 ⊢ ((𝜑 ∧ (𝑥 ∈ 𝐵 ∧ 𝑦 ∈ 𝐵)) → (𝐹‘𝑥) ∈ (Base‘𝐷))
13	10	ffvelcdmda 7083	. . . . . . 7 ⊢ ((𝜑 ∧ 𝑦 ∈ 𝐵) → (𝐹‘𝑦) ∈ (Base‘𝐷))
14	13	adantrl 729	. . . . . 6 ⊢ ((𝜑 ∧ (𝑥 ∈ 𝐵 ∧ 𝑦 ∈ 𝐵)) → (𝐹‘𝑦) ∈ (Base‘𝐷))
15	8, 9, 12, 14, 2	termchomn0 50295	. . . . 5 ⊢ ((𝜑 ∧ (𝑥 ∈ 𝐵 ∧ 𝑦 ∈ 𝐵)) → ¬ ((𝐹‘𝑥)(Hom ‘𝐷)(𝐹‘𝑦)) = ∅)
16		biimt 363	. . . . 5 ⊢ (¬ ((𝐹‘𝑥)(Hom ‘𝐷)(𝐹‘𝑦)) = ∅ → (¬ (𝑥𝐻𝑦) = ∅ ↔ (¬ ((𝐹‘𝑥)(Hom ‘𝐷)(𝐹‘𝑦)) = ∅ → ¬ (𝑥𝐻𝑦) = ∅)))
17	15, 16	syl 18	. . . 4 ⊢ ((𝜑 ∧ (𝑥 ∈ 𝐵 ∧ 𝑦 ∈ 𝐵)) → (¬ (𝑥𝐻𝑦) = ∅ ↔ (¬ ((𝐹‘𝑥)(Hom ‘𝐷)(𝐹‘𝑦)) = ∅ → ¬ (𝑥𝐻𝑦) = ∅)))
18		con34b 319	. . . 4 ⊢ (((𝑥𝐻𝑦) = ∅ → ((𝐹‘𝑥)(Hom ‘𝐷)(𝐹‘𝑦)) = ∅) ↔ (¬ ((𝐹‘𝑥)(Hom ‘𝐷)(𝐹‘𝑦)) = ∅ → ¬ (𝑥𝐻𝑦) = ∅))
19	17, 18	bitr4di 292	. . 3 ⊢ ((𝜑 ∧ (𝑥 ∈ 𝐵 ∧ 𝑦 ∈ 𝐵)) → (¬ (𝑥𝐻𝑦) = ∅ ↔ ((𝑥𝐻𝑦) = ∅ → ((𝐹‘𝑥)(Hom ‘𝐷)(𝐹‘𝑦)) = ∅)))
20	19	2ralbidva 3229	. 2 ⊢ (𝜑 → (∀𝑥 ∈ 𝐵 ∀𝑦 ∈ 𝐵 ¬ (𝑥𝐻𝑦) = ∅ ↔ ∀𝑥 ∈ 𝐵 ∀𝑦 ∈ 𝐵 ((𝑥𝐻𝑦) = ∅ → ((𝐹‘𝑥)(Hom ‘𝐷)(𝐹‘𝑦)) = ∅)))
21	7, 20	bitr4d 285	1 ⊢ (𝜑 → (𝐹(𝐶 Full 𝐷)𝐺 ↔ ∀𝑥 ∈ 𝐵 ∀𝑦 ∈ 𝐵 ¬ (𝑥𝐻𝑦) = ∅))

This proof depends on syntax axioms:  ¬ wn 3   → wi 4   ↔ wb 209   ∧ wa 401   = wceq 1570   ∈ wcel 2146  ∀wral 3081  ∅c0 4286   class class class wbr 5111  ‘cfv 6540  (class class class)co 7416  Basecbs 17287  Hom chom 17339   Func cfunc 17929   Full cful 17979  TermCatctermc 50283

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 7738

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 7373  df-ov 7419  df-oprab 7420  df-mpo 7421  df-1st 7988  df-2nd 7989  df-map 8828  df-ixp 8898  df-cat 17742  df-cid 17743  df-func 17933  df-full 17981  df-thinc 50229  df-termc 50284

This theorem is used by:  fulltermc2  50323