Metamath Proof Explorer


Theorem bj-endmnd

Description: The monoid of endomorphisms on an object of a category is a monoid. (Contributed by BJ, 5-Apr-2024) (Proof modification is discouraged.)

Ref Expression
Hypotheses bj-endval.c φ C Cat
bj-endval.x φ X Base C
Assertion bj-endmnd Could not format assertion : No typesetting found for |- ( ph -> ( ( End ` C ) ` X ) e. Mnd ) with typecode |-

Proof

Step Hyp Ref Expression
1 bj-endval.c φ C Cat
2 bj-endval.x φ X Base C
3 1 2 bj-endbase Could not format ( ph -> ( Base ` ( ( End ` C ) ` X ) ) = ( X ( Hom ` C ) X ) ) : No typesetting found for |- ( ph -> ( Base ` ( ( End ` C ) ` X ) ) = ( X ( Hom ` C ) X ) ) with typecode |-
4 3 eqcomd Could not format ( ph -> ( X ( Hom ` C ) X ) = ( Base ` ( ( End ` C ) ` X ) ) ) : No typesetting found for |- ( ph -> ( X ( Hom ` C ) X ) = ( Base ` ( ( End ` C ) ` X ) ) ) with typecode |-
5 1 2 bj-endcomp Could not format ( ph -> ( +g ` ( ( End ` C ) ` X ) ) = ( <. X , X >. ( comp ` C ) X ) ) : No typesetting found for |- ( ph -> ( +g ` ( ( End ` C ) ` X ) ) = ( <. X , X >. ( comp ` C ) X ) ) with typecode |-
6 5 eqcomd Could not format ( ph -> ( <. X , X >. ( comp ` C ) X ) = ( +g ` ( ( End ` C ) ` X ) ) ) : No typesetting found for |- ( ph -> ( <. X , X >. ( comp ` C ) X ) = ( +g ` ( ( End ` C ) ` X ) ) ) with typecode |-
7 eqid Base C = Base C
8 eqid Hom C = Hom C
9 eqid comp C = comp C
10 1 3ad2ant1 φ x X Hom C X y X Hom C X C Cat
11 2 3ad2ant1 φ x X Hom C X y X Hom C X X Base C
12 simp3 φ x X Hom C X y X Hom C X y X Hom C X
13 simp2 φ x X Hom C X y X Hom C X x X Hom C X
14 7 8 9 10 11 11 11 12 13 catcocl φ x X Hom C X y X Hom C X x X X comp C X y X Hom C X
15 1 adantr φ x X Hom C X y X Hom C X z X Hom C X C Cat
16 2 adantr φ x X Hom C X y X Hom C X z X Hom C X X Base C
17 simpr φ x X Hom C X y X Hom C X z X Hom C X x X Hom C X y X Hom C X z X Hom C X
18 simp3 x X Hom C X y X Hom C X z X Hom C X z X Hom C X
19 17 18 syl φ x X Hom C X y X Hom C X z X Hom C X z X Hom C X
20 simp2 x X Hom C X y X Hom C X z X Hom C X y X Hom C X
21 17 20 syl φ x X Hom C X y X Hom C X z X Hom C X y X Hom C X
22 simp1 x X Hom C X y X Hom C X z X Hom C X x X Hom C X
23 17 22 syl φ x X Hom C X y X Hom C X z X Hom C X x X Hom C X
24 7 8 9 15 16 16 16 19 21 16 23 catass φ x X Hom C X y X Hom C X z X Hom C X x X X comp C X y X X comp C X z = x X X comp C X y X X comp C X z
25 eqid Id C = Id C
26 7 8 25 1 2 catidcl φ Id C X X Hom C X
27 1 adantr φ x X Hom C X C Cat
28 2 adantr φ x X Hom C X X Base C
29 simpr φ x X Hom C X x X Hom C X
30 7 8 25 27 28 9 28 29 catlid φ x X Hom C X Id C X X X comp C X x = x
31 7 8 25 27 28 9 28 29 catrid φ x X Hom C X x X X comp C X Id C X = x
32 4 6 14 24 26 30 31 ismndd Could not format ( ph -> ( ( End ` C ) ` X ) e. Mnd ) : No typesetting found for |- ( ph -> ( ( End ` C ) ` X ) e. Mnd ) with typecode |-