We consider proof systems for effectively propositional logic. First, we show that propositional resolution for effectively propositional logic may have exponentially longer refuta...
Abstract. In previous work, we showed the importance of distinguishing "I know that X = Y " from "I don't know that X = Y ". In this paper we look at effec...
A survey of effective characterizations of tree logics. If L is a logic, then an effective characterization for L is an algorithm, which inputs a tree automaton and replies if the...
In this paper we introduce a logic for parametric polymorphism. Just as LCF is a logic for the simply-typed λ-calculus with recursion and arithmetic, our logic is a logic for Sys...
We show the non-arithmeticity of 1st order theories of lattices of n sentences modulo provable equivalence in a formal theory, of diagonalizable algebras of a wider class of arithm...