Description: Stoic logic Thema 1 (part b). The other part of thema 1 of Stoic logic; see stoic1a . (Contributed by David A. Wheeler, 16-Feb-2019)
Ref | Expression | ||
---|---|---|---|
Hypothesis | stoic1.1 | |- ( ( ph /\ ps ) -> th ) |
|
Assertion | stoic1b | |- ( ( ps /\ -. th ) -> -. ph ) |
Step | Hyp | Ref | Expression |
---|---|---|---|
1 | stoic1.1 | |- ( ( ph /\ ps ) -> th ) |
|
2 | 1 | ancoms | |- ( ( ps /\ ph ) -> th ) |
3 | 2 | stoic1a | |- ( ( ps /\ -. th ) -> -. ph ) |