Theorem frege132

Description: Lemma for frege133 . Proposition 132 of Frege1879 p. 86. (Contributed by RP, 9-Jul-2020) (Proof modification is discouraged.)

	Ref	Expression
Hypotheses	frege130.m	|- M e. U
	frege130.r	|- R e. V
Assertion	frege132	|- ( ( R hereditary ( ( `' ( t+ ` R ) " { M } ) u. ( ( ( t+ ` R ) u. _I ) " { M } ) ) -> ( X ( t+ ` R ) M -> ( X ( t+ ` R ) Y -> ( -. Y ( t+ ` R ) M -> M ( ( t+ ` R ) u. _I ) Y ) ) ) ) -> ( Fun `' `' R -> ( X ( t+ ` R ) M -> ( X ( t+ ` R ) Y -> ( -. Y ( t+ ` R ) M -> M ( ( t+ ` R ) u. _I ) Y ) ) ) ) )

Proof

Step	Hyp	Ref	Expression
1		frege130.m	|- M e. U
2		frege130.r	|- R e. V
3	1 2	frege131	|- ( Fun `' `' R -> R hereditary ( ( `' ( t+ ` R ) " { M } ) u. ( ( ( t+ ` R ) u. _I ) " { M } ) ) )
4		frege9	|- ( ( Fun `' `' R -> R hereditary ( ( `' ( t+ ` R ) " { M } ) u. ( ( ( t+ ` R ) u. _I ) " { M } ) ) ) -> ( ( R hereditary ( ( `' ( t+ ` R ) " { M } ) u. ( ( ( t+ ` R ) u. _I ) " { M } ) ) -> ( X ( t+ ` R ) M -> ( X ( t+ ` R ) Y -> ( -. Y ( t+ ` R ) M -> M ( ( t+ ` R ) u. _I ) Y ) ) ) ) -> ( Fun `' `' R -> ( X ( t+ ` R ) M -> ( X ( t+ ` R ) Y -> ( -. Y ( t+ ` R ) M -> M ( ( t+ ` R ) u. _I ) Y ) ) ) ) ) )
5	3 4	ax-mp	|- ( ( R hereditary ( ( `' ( t+ ` R ) " { M } ) u. ( ( ( t+ ` R ) u. _I ) " { M } ) ) -> ( X ( t+ ` R ) M -> ( X ( t+ ` R ) Y -> ( -. Y ( t+ ` R ) M -> M ( ( t+ ` R ) u. _I ) Y ) ) ) ) -> ( Fun `' `' R -> ( X ( t+ ` R ) M -> ( X ( t+ ` R ) Y -> ( -. Y ( t+ ` R ) M -> M ( ( t+ ` R ) u. _I ) Y ) ) ) ) )