Metamath Proof Explorer


Theorem ifpim1

Description: Restate implication as conditional logic operator. (Contributed by RP, 20-Apr-2020)

Ref Expression
Assertion ifpim1
|- ( ( ph -> ps ) <-> if- ( -. ph , T. , ps ) )

Proof

Step Hyp Ref Expression
1 tru
 |-  T.
2 1 olci
 |-  ( -. -. ph \/ T. )
3 2 biantrur
 |-  ( ( -. ph \/ ps ) <-> ( ( -. -. ph \/ T. ) /\ ( -. ph \/ ps ) ) )
4 imor
 |-  ( ( ph -> ps ) <-> ( -. ph \/ ps ) )
5 dfifp4
 |-  ( if- ( -. ph , T. , ps ) <-> ( ( -. -. ph \/ T. ) /\ ( -. ph \/ ps ) ) )
6 3 4 5 3bitr4i
 |-  ( ( ph -> ps ) <-> if- ( -. ph , T. , ps ) )