Expressive power First-degree entailment Nonreflexive logic Nontransitive logic Sequent calculus Actuality Actuality operator Analytic containment Argument Place Atomic Part Counterfactual modal epistemology Counterpossible conditionals Dialogical logic Epistemic closure Epistemic logic Flexible Relation Impossible worlds Justification logic Logical pluralism Many-valued logic Metainferences Modal logic Non-classical logic Non-standard quantification Nonvacuism Notational variance Ontological Commitment Plural Logic Proof theory Prover–Skeptic games