The study aims at a change of perspective. Instead of focussing on language variation itself, it investigates the attitudes displayed by 16th-18th century grammarians concerned with the teaching of French as a foreign language. Perusal of the diasystematic marking practice employed in teaching manuals generates conclusions about the development of marking practice in the period in question, both in the context of these manuals themselves and in terms of the history of the language and of discourses on language philosophy, language policy and foreign-language instruction.