Psychometric and Piagetian intelligences: Toward resolution of controversy

Whether “psychometric” and “Piagetian” kinds of intelligence, as measured by instruments designed to measure these constructs, are the same or different is regarded as a question of whether they have the same or different courses of development with age. While factor analysis may not be fully adequate for investigation of this question, use of this technique with variables reflecting chronological age variation must involve elimination of the age effect in order to assess relations among the constructs measured. Humphreys and Parsons (1979) were justified in partialing out age in their reanalysis of a study by Stephens, McLaughlin, Miller, and Glass (1972), to show that the two constructs are highly correlated and possibly identical in the sample studied. Reanalyses of studies by DeVries and Kohlberg (1977) and by DeVries (1974) yield somewhat conflicting results on the identity between psychometric and Piagetian intelligences. The former study does not yield a convincing separation between them, whereas the latter suggests that they can be distinguished, though substantially correlated and both loaded with a general factor. Problems in further investigating the issue are discussed.