Most of the psychological studies of race differences have dealt with the comparative intelligence of Negroes and whites. The results of these investigations can be readily summarized, but interpretation is quite another matter. The many studies—over 170 in all—have shown small but consistent differences in favor of the whites. These differences are not considered substantial, and they are far smaller than the differences found within each of the groups. In fact, the range of IQs overlaps completely, since both Negroes and whites are found in all categories of intelligence from the lowest to the highest.Some investigators attribute these differences to heredity, others to environment. Those who believe there is a basic inborn difference argue that the scores show a difference on all educational levels, on nonverbal as well as verbal tests, in Northern as well as Southern areas, and in areas where the cultural environments of Negro and white appear to be closely alike (Shuey,1958) . On the other hand, those who believe that the differences are largely if not wholly due to environmental factors offer a different interpretation of many of these findings and point to specific investigations that call them into question. They point out that the most widely used intelligence tests probably favor whites because the items are largely based on middleclass experience. They cite studies that show no significant differences between white and Negro children on the infant and preschool levels (Pasamanick, 1946), and studies which indicate that the differences in IQ tend to decrease in size when Negroes and whites have approximately the same socioeconomic status and educational opportunity. They point out that the IQ scores of Southern children who have migrated north tend to increase regularly as they go through the Northern schools, until they closely approximate the scores of their white classmates (Klineberg, 1935; Lee, 1951).There is, then, a fairly sharp division of opinion on this question at the present time. Berelson and Steiner (1964) summarize the controversy in these words: “It is probably fair to say that many specialists acknowledge a consistent difference in test scores in favor of the whites, but then disagree on how the difference is to be interpreted: whether it is to be assigned to hereditary origin or to socioeconomic factors that characterize the disadvantaged position of the Negroes. Certainly the large majority of social scientists . . . believes that differences in intelligence scores between Negroes and whites in the United States are directly attributable to such environmental differences as educational opportunity and class position.”It is hard to make a fair comparison between races in the United States, since socioeconomic differences pose a major problem—but it is even more difficult where there are both language and cultural barriers. People in Asia and Africa are rarely accustomed to the idea of being tested, usually have little or no experience with the type of items given on the verbal or even the performance tests—and so far no truly culture-free or culture-fair tests have been devised. However, an objective evaluation of Oriental culture would certainly argue against any notion ofthe inferiority of the Mongoloid race. Moreover, Japanese and Chinese children who have been educated in the United States make the same scores, on the average, as white Americans; and as Garth (1935) has shown, American Indian children who are raised in foster homes under the same conditions as white children score considerably higher than their own brothers and sisters living on the reservation: 102 IQ as compared with 87.5. In the light of present knowledge, then, the majority of psychologists would probably agree that inborn differences between the races have not been proved to exist. A few studies have been made of temperament. There is no evidence that such characteristics as the proverbial stolidity of the American Indian or the tranquillity of the Oriental are universal among these groups, or that they are due to hereditary tendencies. Simpson and Yinger (1953) have concluded that at present “no objective generalizations can be made on the question of race and temperament,” and Klineberg (1957) has stated that “the correlations between traits of intelligence or temperament, on the one hand, and anatomical characteristics (stature, skin color, shape of head, size of head, height of forehead, and so on), on the other, have almost invariably yielded results of no predictive value.”Studies of the sensory characteristics among different racial and social groups have led to the same conclusion. There is a widespread opinion on the basis of hearsay and anecdote that primitive people have keener senses than people from more advanced cultures. It cannot be denied that some groups do develop their sense of smell or vision or hearing more fully than others when they are especially dependent on them for survival—but this does not mean that there are basic inborn differences. Woodworth gave extensive sensory acuity tests to a group of three hundred.Negritos, Eskimos, Ainus, Philippinos, Patagonians, and American Indians at the St. Louis World’s Fair in 1904, and concluded that there was no significant difference between one group and another, although there were wide individual differences.