Conditionals as topics in discourse

Conditional sentences — more specifically, the protasis "X" in sentences of the form "if X, then Y" — have been defined both grammatically and functionally as topics. Some scholars (for example Haiman 1978) claim that conditionals have this status regardless of their syntactic position; others (for example Ford and Thompson 1986) find that conditionals are topics only when they are preposed. My paper is an analysis of conditional sentences in three different discourse genres (narrative, description, exposition). I focus on the relationship between clause order ("if X, Y" vs. "Y, if X") and two different notions inherent in the definition of topic (the notions of "givenness" and "background for"). By locating the analysis within discourse, I show that the dual nature of topic — and its effect on clause order — can only be understood by considering different types and levels of communicative and message-based topics.