This paper proposes an argumentative semantic description of the IMPARFAIT, compatible with both Anscombre's and Ducrot's pragmatic observations. The two main hypotheses put forward state that 1: the argumentative conclusion of an utterance always concerns its topic and 2: the French imparfait's meaning is the instruction that the argumentative conclusion of any utterance containing it regards the temporal discursive space of that utterance. Only after the first characteristic step a derived argumentative movement can occur.