ABSTRACT

It is frequently assumed that interpretational errors can explain reasoning errors. However, the evidence for this position has heretofore been less than convincing. Newstead (1995) failed to show expected relations between Gricean implicatures (Grice, 1975) and reasoning errors, and different measures of illicit conversion (Begg & Denny, 1969; Chapman & Chapman, 1959) frequently fail to correlate in the expected fashion (Newstead, 1989; 1990). This paper examines the relation between interpretation and reasoning using the more configurational approach to classifying subjects' interpretation patterns, described in Stenning & Cox (1995). There it is shown that subjects' interpretational errors tend to fall into clusters of properties defined in terms of rashness, hesitancy and the subject/predicate structure of inferences. First, we show that interpretations classified by illicit conversion errors, though correlated with fallacious reasoning, are equally correlated with errors which cannot be due to conversion of premisses. Then we explore how the alternative method of subject profiling in terms of hesitancy, rashness and subject/predicate affects syllogistic reasoning performance, through analysis in terms of both general reasoning accuracy and the Figural Effect (Johnson-Laird & Bara, 1984). We show that subjects assessed as rash on the interpretation tasks show consistent characteristic error patterns on the syllogistic reasoning task, and that hesitancy, and possibly rashness, interact, with the Figural Effect.