In Reply to McManus: Harping on Income Inequality Ignores the Data

“The Economist noted: ‘Just as ideas about inequality have completed their march from the Academy to the frontlines of politics, researchers have begun to look again. And some are wondering whether inequality has risen as much as claimed—or, by some measures, at all.'”

So I find that I am again called upon to cross intellectual swords with Professor Matt McManus, who is a quite able and talented foe. Regrettably, McManus has now seen fit to offer a favorable review of Michael Brooks’ new book Against the Web: A Cosmopolitan Answer to the New Right, even though Brooks is unable even to listen to contrary scientific evidence that severely undermines his misguided worldview—let alone carefully evaluate it. This is very sad. But let’s start at the beginning. Early in his review, McManus offers that, “To its fiercest critics, the IDW [Intellectual Dark Web] is a screen for advancing controversial views about race, ethnicity, and capitalism under the pretentious veil of being reasonable.” Then, McManus immediately adds that he simply wishes that “…the more sophisticated members of the IDW took their ideological opponents seriously enough to mount well-reasoned criticisms. All too often, figures such as Peterson and Shapiro take pot shots at straw men, rather than actually dealing with progressive arguments in a rigorous way.” Now, I am clearly unable to comment on the intellectual stature of either a Peterson or  Shapiro; however, as a retired economist who taught at the college level, I do believe that I am qualified to accept McManus’ challenge. Here is my attempt to deal with progressive arguments in a rigorous manner.

I assert that the primary goal of progressive movements is to attempt to level existing economic inequalities. And, it is a fact that inequalities exist in the United States, but they are almost always solidly rooted in immutable psychological traits such as IQ, industriousness, honesty, creativity, courage, etc. Take IQ, for example. According to the National Longitudinal Survey of Youth by age 28 to 36, the top 10% in cognitive ability have a median earned income of 4.8 times the median for the bottom 10%. Indeed,  as 1994 book The Bell Curve asserts in part one (“The Emergence of a Cognitive Elite”), IQ is one of the best single predictors of job productivity. More recently, researchers have found that DNA plays a role in social stratification. These investigators concluded that “Human DNA polymorphisms vary across geographic regions, with the most commonly observed variation reflecting distant ancestry differences.”

For further proof that psychological traits are firmly riveted in nature and not in nurture, one need only read Robert Plomin’s 2018 book Blueprint: How DNA Makes Us Who We Are, which is one of the most recent scholarly works on the psychology of human genetics. In Blueprint, Plomin, one of the very top experts in the field of behavioral genetics, asserts that “A century of genetic research shows that DNA differences inherited from our parents are the consistent life-long sources of our psychological individuality—the ‘Blueprint’ that makes us who we are.” Plomin also reports that “… genetics explain more of our psychological differences—not just mental health and school achievement but all psychological traits, from personality to intellectual abilities. Nature, not nurture is what makes us who we are.” Relatedly, the Dec. 14, 2018 issue of Scientific American contains a very brief essay by Plomin entitled “In the Nature-Nurture War, Nature Wins.” In it, Plomin admits that “Environmental influences are important…too, but they are largely unsystematic, unstable and idiosyncratic—in a word, random.” (Emphasis added.) Plomin continues, “These findings call for a radical rethink about parenting, education and the events that shape our lives. It also provides a novel perspective on equal opportunity, social mobility and the structure of society.” I have, thus far, been unable to get Brooks to touch Plomin’s book—let alone read it and then (perish the thought) actually think about the impact of Plomin’s work on progressive dogma.