Development of syllogistic reasoning

We investigated the syllogistic reasoning of children 9-10 years of age, adolescents, and adults. Their performance on five tasks that theoretically might measure components of such reasoning was examined: the interpretation of quantifiers such as some and all; the referential integration of assertions; the search for counterexamples to generalizations; the perception of identical shapes within figures; and the processing capacity of working memory. Syllogistic ability improved reliably with age, though even the youngest subjects were able to draw valid conclusions well above chance to one-model syllogisms. Performance on two of the component tasks also improved reliably with age: the detection of identities, and the capacity of working memory. Multiple regressions showed that performance on these two tasks also accounted for some of the variance in syllogistic reasoning. Performance on the other three tasks was at about adult level by the age of 9. We accordingly examined performance with a group of 7-year-old children and discovered that they also performed at better than chance with one-model syllogisms. Our results support three main conclusions: young children are capable of syllogistic reasoning (contrary to the claims of Inhelder & Piaget, 1964); there is a significant development of ability from childhood to adulthood; and it is possible to identify some of the major components of this improvement.
Development of the ability to reason How could children who do not know how to reason validly acquire the ability to do so? This question is deeply puzzling - so [...]