Theorem dfvd1impr 38792

Description: Right-to-left part of definition of virtual deduction. (Contributed by Alan Sare, 21-Apr-2011.) (Proof modification is discouraged.) (New usage is discouraged.)

Assertion

Ref	Expression
dfvd1impr	|- ( ( ph -> ps ) -> (. ph ->. ps ). )

Proof of Theorem dfvd1impr

Step	Hyp	Ref	Expression
1		df-vd1 38786	. 2 |- ( (. ph ->. ps ). <-> ( ph -> ps ) )
2	1	biimpri 218	1 |- ( ( ph -> ps ) -> (. ph ->. ps ). )

Syntax hints:   -> wi 4   (.wvd1 38785

This theorem was proved from axioms:  ax-mp 5  ax-1 6  ax-2 7  ax-3 8

This theorem depends on definitions:  df-bi 197  df-vd1 38786

This theorem is referenced by:  gen11  38841