ABSTRACT
Let us take stock. In Chapter 1 we posed two questions. The first concerned the difference, if any, between the mental derivations of children and adolescents for intuitive, deductive arguments. On the basis of evidence presented in Chapters 4-7, we tentatively concluded that the mental derivations of these two age groups are largely the same. The second question posed in Chapter 1 concerned the grounds on which two deduction models generating the same derivations can be empirically distinguished. To make such a distinction, in Chapter 8 we formulated an empirical criterion called “explanatory adequacy.” The criterion of explanatory adequacy is linked to theories of human conceptual domains, in particular, to proposals about the set of formal properties of models that help to pick out the natural conceptual domains and exclude the others. Hence, to begin to speculate about the explanatory adequacy of the deduction model of Chapter 3, Mq, we need concrete suggestions as to the formal properties that figure in a true theory of human conceptual domains. This chapter makes such proposals. They are given a preliminary test in Part 4.
