Metamath Proof Explorer


Theorem inclfusubc

Description: The "inclusion functor" from a subcategory of a category into the category itself. (Contributed by AV, 30-Mar-2020)

Ref Expression
Hypotheses inclfusubc.j ⊢ φ → J ∈ Subcat ⁡ C
inclfusubc.s ⊢ S = C ↾ cat J
inclfusubc.b ⊢ B = Base S
inclfusubc.f ⊢ φ → F = I ↾ B
inclfusubc.g ⊢ φ → G = x ∈ B , y ∈ B ⟼ I ↾ x J y
Assertion inclfusubc ⊢ φ → F S Func C G

Proof

Step Hyp Ref Expression
1 inclfusubc.j ⊢ φ → J ∈ Subcat ⁡ C
2 inclfusubc.s ⊢ S = C ↾ cat J
3 inclfusubc.b ⊢ B = Base S
4 inclfusubc.f ⊢ φ → F = I ↾ B
5 inclfusubc.g ⊢ φ → G = x ∈ B , y ∈ B ⟼ I ↾ x J y
6 fthfunc ⊢ S Faith C ⊆ S Func C
7 eqid ⊢ id func ⁡ S = id func ⁡ S
8 2 7 rescfth ⊢ J ∈ Subcat ⁡ C → id func ⁡ S ∈ S Faith C
9 1 8 syl ⊢ φ → id func ⁡ S ∈ S Faith C
10 6 9 sselid ⊢ φ → id func ⁡ S ∈ S Func C
11 df-br ⊢ F S Func C G ↔ F G ∈ S Func C
12 4 5 opeq12d ⊢ φ → F G = I ↾ B x ∈ B , y ∈ B ⟼ I ↾ x J y
13 2 7 3 idfusubc ⊢ J ∈ Subcat ⁡ C → id func ⁡ S = I ↾ B x ∈ B , y ∈ B ⟼ I ↾ x J y
14 1 13 syl ⊢ φ → id func ⁡ S = I ↾ B x ∈ B , y ∈ B ⟼ I ↾ x J y
15 12 14 eqtr4d ⊢ φ → F G = id func ⁡ S
16 15 eleq1d ⊢ φ → F G ∈ S Func C ↔ id func ⁡ S ∈ S Func C
17 11 16 bitrid ⊢ φ → F S Func C G ↔ id func ⁡ S ∈ S Func C
18 10 17 mpbird ⊢ φ → F S Func C G