Charles Murray uses sociological research to show how white America is dividing into classes based on cognitive ability. Access to college and the college sorting system has facilitated what he calls a 'new upper-class' with its own culture and tastes unique in American history. He posits that higher-IQ individuals are congregating in high-income areas of the country and are increasingly separating themselves from the rest of society. He explores the ramifications of this new dynamic for the working class.