I am studying the algorithm presented in this paper for "Learning conjunctions of Horn clauses".
The algorithm uses equivalence queries and membership queries to produce a formula that is logically equivalent to the unknown formula to be learned.
What I can not understand is how you can use this algorithm in practice since the formula to learn is unknown. If I do not know the formula I can not have an oracle telling me if a hypothesis is logically equivalent to the formula. If I know the formula I do not need an algorithm to learn it.
Is there a way to get an oracle without knowing the explicitly target formula or something I do not see?