Piaget's System of 16 Binary Operations: An Empirical Investigation

Abstract

Abstract Inhelder and Piaget offer a single protocol as their only evidence that a fully developed formal operational thinker uses all 16 binary operations of truth-functional logic. The investigators attempted to replicate the Inhelder-Piaget results with a random sample of 57 subjects (18 9-year-olds, 19 12-year-olds, 20 16-year-olds). Not one of the subjects used more than five of the 16 operations, and there was no developmental trend with regard to the number of operations used (X2 = .4917, p > .05). A trend was manifest, however, since the more developed reasoner used the same operations as the less developed reasoner, but in a more complex and sophisticated manner.