Theorem tsan2

Description: A Tseitin axiom for logical conjunction, in deduction form. (Contributed by Giovanni Mascellani, 24-Mar-2018)

	Ref	Expression
Assertion	tsan2	|- ( th -> ( ph \/ -. ( ph /\ ps ) ) )

Proof

Step	Hyp	Ref	Expression
1		pm3.14	|- ( ( -. ph \/ -. ps ) -> -. ( ph /\ ps ) )
2	1	orcs	|- ( -. ph -> -. ( ph /\ ps ) )
3	2	orri	|- ( ph \/ -. ( ph /\ ps ) )
4	3	a1i	|- ( th -> ( ph \/ -. ( ph /\ ps ) ) )