Theorem fulltermc2 50786

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 7434	. . . 4 ⊢ (𝑥 = 𝑋 → (𝑥𝐻𝑦) = (𝑋𝐻𝑦))
2	1	eqeq1d 2765	. . 3 ⊢ (𝑥 = 𝑋 → ((𝑥𝐻𝑦) = ∅ ↔ (𝑋𝐻𝑦) = ∅))
3	2	notbid 321	. 2 ⊢ (𝑥 = 𝑋 → (¬ (𝑥𝐻𝑦) = ∅ ↔ ¬ (𝑋𝐻𝑦) = ∅))
4		oveq2 7435	. . . 4 ⊢ (𝑦 = 𝑌 → (𝑋𝐻𝑦) = (𝑋𝐻𝑌))
5	4	eqeq1d 2765	. . 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 18095	. . . . . 6 ⊢ (𝐶 Full 𝐷) ⊆ (𝐶 Func 𝐷)
12	11	ssbri 5152	. . . . 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 50785	. . 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 3593	1 ⊢ (𝜑 → ¬ (𝑋𝐻𝑌) = ∅)

This proof depends on syntax axioms:  ¬ wn 3   → wi 4   = wceq 1569   ∈ wcel 2146  ∀wral 3079  ∅c0 4280   class class class wbr 5105  ‘cfv 6546  (class class class)co 7427  Basecbs 17399  Hom chom 17451   Func cfunc 18041   Full cful 18091  TermCatctermc 50746

This proof depends on axioms:  ax-mp 5  ax-1 6  ax-2 7  ax-3 8  ax-gen 1827  ax-4 1841  ax-5 1944  ax-6 2001  ax-7 2042  ax-8 2148  ax-9 2156  ax-10 2179  ax-11 2196  ax-12 2215  ax-ext 2735  ax-rep 5234  ax-sep 5251  ax-nul 5262  ax-pow 5330  ax-pr 5394  ax-un 7758

This proof depends on definitions:  df-bi 210  df-an 402  df-or 862  df-3an 1105  df-tru 1572  df-fal 1582  df-ex 1812  df-nf 1816  df-sb 2101  df-mo 2567  df-eu 2597  df-clab 2742  df-cleq 2755  df-clel 2838  df-nfc 2912  df-ne 2959  df-ral 3080  df-rex 3090  df-rmo 3368  df-reu 3369  df-rab 3416  df-v 3455  df-sbc 3742  df-csb 3851  df-ss 3900  df-dif 4049  df-in 4093  df-un 4153  df-nul 4281  df-if 4485  df-pw 4561  df-sn 4588  df-pr 4590  df-op 4838  df-uni 4870  df-iun 4955  df-br 5106  df-opab 5170  df-mpt 5189  df-id 5549  df-xp 5660  df-rel 5661  df-cnv 5662  df-co 5663  df-dm 5664  df-rn 5665  df-res 5666  df-ima 5667  df-iota 6500  df-fun 6548  df-fn 6549  df-f 6550  df-f1 6551  df-fo 6552  df-f1o 6553  df-fv 6554  df-riota 7384  df-ov 7430  df-oprab 7431  df-mpo 7432  df-1st 8008  df-2nd 8009  df-map 8860  df-ixp 8937  df-cat 17854  df-cid 17855  df-func 18045  df-full 18093  df-thinc 50692  df-termc 50747

This theorem is used by: (None)