Metamath Proof Explorer


Theorem termopropdlem

Description: Lemma for termopropd . (Contributed by Zhi Wang, 26-Oct-2025)

Ref Expression
Hypotheses initopropd.1
|- ( ph -> ( Homf ` C ) = ( Homf ` D ) )
initopropd.2
|- ( ph -> ( comf ` C ) = ( comf ` D ) )
initopropdlem.1
|- ( ph -> -. C e. _V )
Assertion termopropdlem
|- ( ph -> ( TermO ` C ) = ( TermO ` D ) )

Proof

Step Hyp Ref Expression
1 initopropd.1
 |-  ( ph -> ( Homf ` C ) = ( Homf ` D ) )
2 initopropd.2
 |-  ( ph -> ( comf ` C ) = ( comf ` D ) )
3 initopropdlem.1
 |-  ( ph -> -. C e. _V )
4 termofn
 |-  TermO Fn Cat
5 ssv
 |-  Cat C_ _V
6 simpr
 |-  ( ( ph /\ D e. Cat ) -> D e. Cat )
7 eqid
 |-  ( Base ` D ) = ( Base ` D )
8 eqid
 |-  ( Hom ` D ) = ( Hom ` D )
9 6 7 8 termoval
 |-  ( ( ph /\ D e. Cat ) -> ( TermO ` D ) = { a e. ( Base ` D ) | A. b e. ( Base ` D ) E! h h e. ( b ( Hom ` D ) a ) } )
10 fvprc
 |-  ( -. C e. _V -> ( Homf ` C ) = (/) )
11 3 10 syl
 |-  ( ph -> ( Homf ` C ) = (/) )
12 1 11 eqtr3d
 |-  ( ph -> ( Homf ` D ) = (/) )
13 homf0
 |-  ( ( Base ` D ) = (/) <-> ( Homf ` D ) = (/) )
14 12 13 sylibr
 |-  ( ph -> ( Base ` D ) = (/) )
15 14 rabeqdv
 |-  ( ph -> { a e. ( Base ` D ) | A. b e. ( Base ` D ) E! h h e. ( b ( Hom ` D ) a ) } = { a e. (/) | A. b e. ( Base ` D ) E! h h e. ( b ( Hom ` D ) a ) } )
16 rab0
 |-  { a e. (/) | A. b e. ( Base ` D ) E! h h e. ( b ( Hom ` D ) a ) } = (/)
17 15 16 eqtrdi
 |-  ( ph -> { a e. ( Base ` D ) | A. b e. ( Base ` D ) E! h h e. ( b ( Hom ` D ) a ) } = (/) )
18 17 adantr
 |-  ( ( ph /\ D e. Cat ) -> { a e. ( Base ` D ) | A. b e. ( Base ` D ) E! h h e. ( b ( Hom ` D ) a ) } = (/) )
19 9 18 eqtrd
 |-  ( ( ph /\ D e. Cat ) -> ( TermO ` D ) = (/) )
20 4 3 5 19 initopropdlemlem
 |-  ( ph -> ( TermO ` C ) = ( TermO ` D ) )