Metamath Proof Explorer


Theorem frins3

Description: Well-Founded Induction schema, using implicit substitution. (Contributed by Scott Fenton, 6-Feb-2011) (Revised by Mario Carneiro, 26-Jun-2015)

Ref Expression
Hypotheses frins3.1
|- ( y = z -> ( ph <-> ps ) )
frins3.2
|- ( y = B -> ( ph <-> ch ) )
frins3.3
|- ( y e. A -> ( A. z e. Pred ( R , A , y ) ps -> ph ) )
Assertion frins3
|- ( ( ( R Fr A /\ R Se A ) /\ B e. A ) -> ch )

Proof

Step Hyp Ref Expression
1 frins3.1
 |-  ( y = z -> ( ph <-> ps ) )
2 frins3.2
 |-  ( y = B -> ( ph <-> ch ) )
3 frins3.3
 |-  ( y e. A -> ( A. z e. Pred ( R , A , y ) ps -> ph ) )
4 3 1 frins2
 |-  ( ( R Fr A /\ R Se A ) -> A. y e. A ph )
5 2 rspcv
 |-  ( B e. A -> ( A. y e. A ph -> ch ) )
6 4 5 mpan9
 |-  ( ( ( R Fr A /\ R Se A ) /\ B e. A ) -> ch )