Too much to quote from this book. Here’s the ending (lol spoilers)

For many years now it has been practically axiomatic among people in the testing field that the fact of statistical differences between racial populations should not be permitted to influence the treatment accorded to individuals of any race—in education, employment, legal justice, and political and civil rights. The well-established finding of a wide range of individual differences in IQ and other abilities within all major racial populations, and the great amount of overlap of their frequency distributions, absolutely contradicts the racist philosophy that persons of different races should be treated dif­ferently, one and all, only by reason of their racial origins. Those who would accord any treatment to individuals solely by virtue of their race will find no rational support in any of the scientific findings from psychological testing or present-day theories of differential psychology. That much seems certain. Righting the past wrongs of racial discrimination cannot be furthered by blaming the mental tests (which we admittedly should continue to improve and to use more wisely), but by prohibiting racial discrimination in any form, by legal sanctions when necessary, and by seeking equal educational opportunities for members of those minority groups that have been denied them in the past, so they can compete fairly, as individuals, in selection for employment, technical training, or higher education, without condescending dispensations.