Abstract

Explaining difficult ideas to lay readers is an important and frequently needed writing skill. When explaining, writers must recognize and overcome the confusions that lay readers may experience in learning abstract concepts. To date, there has been little study of this demanding writing skill. Consequently, this article identifies a particular class of explanatory discourse and proposes working hypotheses about the types of knowledge likely to be associated with skill in this genre. These hypotheses are explored through a study of individual differences in explanatory writing skill among 169 college students. The results of the study showed that variations in the accuracy and adaptiveness of the students' explanations were partially accounted for by measures of topic knowledge, social cognition, and discourse knowledge. A discourse knowledge index and a topic knowledge index were correlated with explanatory writing skill. Cognitive complexity, a measure of social cognition, was associated with adaptiveness in explaining but not accuracy. These findings suggest that explanatory skill is a function of several types of knowledge and that it may be as dependent on discourse or rhetorical knowledge as it is on topical expertise.