The study provides a theoretical and methodological grounding for historical dialogue research by engaging in a critical discussion and systematic dovetailing of approaches deriving from conversation analysis, dialogue grammar, and the history of mentality. It subsequently applies the results to didactic dialogues from the 17th and 18th centuries. The focus is on the didactic dialogue as both a subject of and a language-change factor in the linguistic practice of school instruction. For one suspended moment in the history of the language, it is thus possible to engage in closer observation of the evolution of standard New High German. A major turning-point in the history of educational communication is brought into a clearer perspective by tracing the development from religious catechetics to philanthropic Socratic maieutics.