Definition df-vd1 38786

Description: Definition of virtual deduction. (Contributed by Alan Sare, 21-Apr-2011.) (New usage is discouraged.)

Assertion

Ref	Expression
df-vd1	|- ( (. ph ->. ps ). <-> ( ph -> ps ) )

Detailed syntax breakdown of Definition df-vd1

Step	Hyp	Ref	Expression
1		wph	. . 3 wff ph
2		wps	. . 3 wff ps
3	1, 2	wvd1 38785	. 2 wff (. ph ->. ps ).
4	1, 2	wi 4	. 2 wff ( ph -> ps )
5	3, 4	wb 196	1 wff ( (. ph ->. ps ). <-> ( ph -> ps ) )

This definition is referenced by:  in1  38787  dfvd1ir  38789  dfvd1imp  38791  dfvd1impr  38792  dfvd2an  38798  dfvd3an  38810