Description: Restate implication as conditional logic operator. (Contributed by RP, 25-Apr-2020)
| Ref | Expression | ||
|---|---|---|---|
| Assertion | ifpim3 | |- ( ( ph -> ps ) <-> if- ( ph , ps , -. ph ) ) |
| Step | Hyp | Ref | Expression |
|---|---|---|---|
| 1 | simpl | |- ( ( ph /\ ps ) -> ph ) |
|
| 2 | orc | |- ( ph -> ( ph \/ ps ) ) |
|
| 3 | ifpim23g | |- ( ( ( ph -> ps ) <-> if- ( ph , ps , -. ph ) ) <-> ( ( ( ph /\ ps ) -> ph ) /\ ( ph -> ( ph \/ ps ) ) ) ) |
|
| 4 | 1 2 3 | mpbir2an | |- ( ( ph -> ps ) <-> if- ( ph , ps , -. ph ) ) |