Fast-forward to 2010. Murray paints equally disturbing pictures of both the middle class and elites today. Rising divorce rates and more single-parent households are placing financial pressures on Middle America at the same time employers are becoming much less paternalistic as they address the forces of globalization.

Today, the elites and the middle class occupy separate universes. Politically incorrect though it may sound, Murray ascribes many of the problems afflicting white middle-class America to the same causes that Daniel Patrick Moynihan controversially attributed to black America's lack of advancement more than 40 years ago.

Working-class whites used to have a strong work ethic, but Murray argues that's a thing of the past. As evidence, he notes that in 1968, 97% of white males between 30 and 49 years old whose highest educational attainment was no more than a high school diploma were participating in the labor force, either by working or seeking employment. Before the Great Recession was apparent in March 2008, that figure had declined to 88%, meaning one out of eight white working-class men wasn't even looking for a job.

Furthermore, Murray notes that the percentage of these men with jobs who are working less than 40 hours a week has climbed from 10% in 1960 to 20% in 2008. But one could easily argue that this is the result of changing dynamics in the labor market favoring project workers and freelancers over full-timers with their attendant benefits, not some supposed lack of work ethic.

Murray relishes inciting controversies that will inflame mainstream discourse and that other sociologists assiduously avoid. In his book The Bell Curve, he attacked affirmative action. Through the granular analysis of IQ and other testing statistics, he essentially argued, among other things, that while many intelligent young African-Americans at Ivy League schools had the brains for universities like Columbia and Brown, few truly belonged at Harvard, Murray's alma mater. Well, excuse me.

Murray's view of the disconnected white elites is equally harsh. It's not just the CEOs and their "unseemly" compensation he singles out. From Beverly Hills to Chestnut Hill to Manhasset to Hillsborough, these elites live in their own cocoons and look down on Middle America in a way elites in the post-World War II era never did. Their view of the middle class could easily be encapsulated by James Carville's unfortunate comment about Paula Jones, when he said, "Drag a hundred dollar bill through a trailer park and there's no telling what you'll come up with."

Intelligence, rather than income, prints most of the admission tickets to the new upper class. Because they often marry fellow graduates of the same elite universities, their children tend to be intelligent but wind up living in ever more insular worlds. The income and wealth just naturally follow. According to several reviews, Murray himself chose to raise his family in Burkittsville, Md., precisely so his own children could grow up outside some elitist Beltway bubble.

The flashpoints both Frank's and Murray's theses raise about our fragmenting society represent conversations worth having. Frank is undoubtedly correct that income and wealth are fluid and vary over one's career, but their variances are much higher for certain business owners and financial services executives than they are for professionals like doctors and lawyers.

Murray's troubling analysis of an increasingly stratified society pinpoints several serious problems, yet he fails to prove that declining morality is the root cause. Indeed, his decision to pick 1960, the midpoint of a unique era in American economic history, as a starting point inevitably influences his declinist conclusions.

At that time, the U.S. was the world's only dominant economic superpower. Nations like Germany and Japan were still rebuilding their industrial infrastructure, while the Soviet Union was locked in a losing arms race that consumed 25% to 30% of its GDP and would eventually bankrupt it.