||Erotetic logic is the study of questions in symbolic logic. Its main issues concern (i) the formalization of different kinds of questions (e.g. yes/no-questions, wh-questions, etc.), (ii) the characterization of their answers and presuppositions, (iii) the definition of relations holding between questions and other lingual entities, and (iv) the setting up of rules and calculi of asking and answering. Post-Fregean logicians have treated questions since the 1920s, but the first attempts at full systems of erotetic logic date appear in the 1960s. Today, there is no agreed-upon mainstream in the field, but rather a handful of different approaches of disparate or unclear relationship to one another.