Exercise logic.propositional.consequence
Description
Prove that formula is a logical consequence of a set of formulas
Derivation
Final term is not finished
p <-> r, q <-> s => ((p -> q) /\ (r -> s)) || (~(p -> q) /\ ~(r -> s))
⇒ logic.propositional.defimpl, initial=TList [TCon logic1.equivalent [TVar "p",TVar "r"],TCon logic1.equivalent [TVar "q",TVar "s"]]p <-> r, q <-> s => ((~p || q) /\ (r -> s)) || (~(p -> q) /\ ~(r -> s))
⇒ logic.propositional.defimplp <-> r, q <-> s => ((~p || q) /\ (r -> s)) || (~(~p || q) /\ ~(r -> s))
⇒ logic.propositional.defimplp <-> r, q <-> s => ((~p || q) /\ (r -> s)) || (~(~p || q) /\ ~(~r || s))
⇒ logic.propositional.demorganorp <-> r, q <-> s => ((~p || q) /\ (r -> s)) || (~~p /\ ~q /\ ~(~r || s))
⇒ logic.propositional.demorganorp <-> r, q <-> s => ((~p || q) /\ (r -> s)) || (~~p /\ ~q /\ ~~r /\ ~s)
⇒ logic.propositional.notnotp <-> r, q <-> s => ((~p || q) /\ (r -> s)) || (p /\ ~q /\ ~~r /\ ~s)
⇒ logic.propositional.notnotp <-> r, q <-> s => ((~p || q) /\ (r -> s)) || (p /\ ~q /\ r /\ ~s)
⇒ fakeabsorptionp <-> r, q <-> s => ((~p || q) /\ (r -> s)) || (p /\ ~q /\ r /\ ~s)