Metamath Proof Explorer


Theorem termoo2

Description: A terminal object is an object in the base set. (Contributed by Zhi Wang, 23-Oct-2025)

Ref Expression
Hypothesis initoo2.b
|- B = ( Base ` C )
Assertion termoo2
|- ( O e. ( TermO ` C ) -> O e. B )

Proof

Step Hyp Ref Expression
1 initoo2.b
 |-  B = ( Base ` C )
2 eqid
 |-  ( Hom ` C ) = ( Hom ` C )
3 termorcl
 |-  ( O e. ( TermO ` C ) -> C e. Cat )
4 1 2 3 istermoi
 |-  ( ( O e. ( TermO ` C ) /\ O e. ( TermO ` C ) ) -> ( O e. B /\ A. b e. B E! h h e. ( b ( Hom ` C ) O ) ) )
5 4 anidms
 |-  ( O e. ( TermO ` C ) -> ( O e. B /\ A. b e. B E! h h e. ( b ( Hom ` C ) O ) ) )
6 5 simpld
 |-  ( O e. ( TermO ` C ) -> O e. B )