IT has been assumed that rigidity is a general factor related to the development of social attitudes. Murphy has stated, "It is of importance to note the very broad base of generality, general rigidity, whtfh serves as the primary source of all specific phenomena in the prejudice area" (4, p. ix). This assumption has been put to some empirical study.The most widely quoted research in this area is the work of Rokeach (11, 12, 13, 14). He stated in his original study, "The basic assumption ... is that one of the characteristics of ethnocentric thinking (i.e., prejudice) is a rigidity or inflexibility of the thinking process" (12, p. 259). Rokeach found that individuals who were ethnocentric on the California Ethnocentrism Scale were also more likely to be rigid in their solution of a series of arithmetic problems. He concluded, "The data clearly indicate that those high in ethnocentrism are more concrete (i.e., rigid) in their mode of thought than those who are low in ethnocentrism" (12, p. 277).In a more recent study (14), Rokeach found that prejudiced individuals gave more concrete definitions of political, economic, and religious concepts while nonprejudiced individuals gave more abstract definitions.Rokeach's work, however, has been criticized by Luchins (6,7,8) on the grounds that the arithmetical problems do not measure deep-seated personality rigidity. Second, he objected to Rokeach's method of combining all persons who made low scores on the attitude scale and defining the resulting group as nonprejudiced. Finally, Luchins noted that no general factor of intellectual rigidity has been unequivocally demonstrated and insisted that this issue is crucial in limiting Rokeach's conclusions.1 Based on a portion of a dissertation submitted in partial fulfillment of the requirements for the degree of Doctor of Philosophy in the Faculty of Philosophy, Columbia University. The writer wishes to acknowledge his indebtedness to Drs. L. F. Shaffer, Irving Lorge, and E. J. Shoben, Jr., for their generous assistance.