Abstract. We provide an interactive method for knowledge acquisition combining approaches from description logic and formal concept analysis. Based on present data, hypothetical rules are formulated and checked against a description eory. We propose an abstract framework (Logical Domain Exploration) for this kind of exploration technique before presenting a concrete instantiation: Relational Exploration. We give a completeness result and provide an overview about some application fields for our approach: machine learning, data mining, and ontology engineering.