Pragmatic-reasoning-schemas theory (PRS theory) suggests a developmental scenario for the acquisition of semantic knowledge about logic particles that is quite different from what is proposed by the mental-logic theory of this volume. PRS theory (e.g., Cheng & Holyoak, 1985; Holland, Holyoak, Nisbett, & Thagard, 1986; Holyoak & Cheng, 1995) claims that reasoning typically uses some context-sensitive schemas that are defined in terms of classes of goals and content. Unlike the sorts of schemas proposed by mentallogic theory, the proposed pragmatic-reasoning schemas are applicable only when their appropriate goals and content are present. Although the PRS theorists have suggested that there are a large number of such schemas (e.g.,
Holyoak & Cheng, 1995), to date only two schemas have been specified-one for permissions and one for obligations-both of which are presented in the form of conditionals, that is, If P then Q.