Department of Educational Psychology


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Published in Developmental Psychology, 15:2 (1979), pp. 104-112. Copyright © 1979 by the American Psychological Association, Inc. Used by permission. “This article may not exactly replicate the final version published in the APA journal. It is not the copy of record.”


It was postulated that formal operational hypothesis-testing ability includes at least three cognitive capacities: (a) implication comprehension, the ability to understand conditional relationships; (b) falsification strategy, the realization that to test a hypothesis, one must seek information that would falsify it; and(c) nonverification insight, the realization that hypotheses are not conclusively verified by supporting data. A total of 24 males in each of Grades 7, 10, and college evaluated data descriptions with respect to each of four hypothesized implication relationships and chose an experiment to test each hypothesis. Results suggested three sequences of qualitative change in hypothesis-testing ability: (a) from no systematic interpretation of conditionals to an implication interpretation, (b) from content-based information seeking to a falsification strategy, and (c) from a symmetrical conception of truth and falsity to a non-verification insight. However, formal operational performance was far from universal, even in college students.