The relationship between formal operations and postformal reasoning was examined by using the Shayer (1978) chemicals problem to assess formal operations and the Commons,et al.(1982) four‐story problem to measure postformal reasoning. The subjects were 35 undergraduate social science and humanities students. None of the subjects who were classified as concrete operational or transitional on the chemicals task showed postformal reasoning. The hypothesis that full format operations are a necessary condition of post‐formal reasoning and the expectation that subjects showing full formal operations are more likely than others to exhibit postformal reasoning was not suppor