Scientific racism has no place in 21st-century academia. Yet somehow, in 2009, Jason Richwine was able to successfully defend a dissertation at Harvard University in which he wrote that Hispanic immigrants have a substantially lower IQ than the white native-born population and that, because of the hereditary nature of IQ, this fact should be taken into consideration when designing immigration policy.

This work is problematic because it is part of a tradition of scientific racism, and because it is based on discredited ideas of intelligence testing and the relationship between racialised categories and genetic makeup.

The US has an ugly history of intelligence testing and immigration policy, and we would do well to avoid repeating that history. In the 19th century, European scientists such as Paul Broca compared the skulls of blacks to those of whites to prove what they thought they already knew - that the white race was intellectually superior to all others. The late Stephen Jay Gould has reviewed these studies and shed light on their deep flaws. Eventually, the science of craniometry lost its appeal and scientists began to try to measure intelligence directly through intelligence testing.

One of the first American psychologists to use intelligence testing was H H Goddard, who adapted a version of the test developed by French psychologist Alfred Binet. Goddard believed that intelligence was measurable and that it was heritable. He took Binet's test to Ellis Island, where he administered it to European immigrants. Goddard found that many arriving immigrants received a low score. Instead of questioning the conditions under which he performed the exam - that is, on recently arrived migrants who barely spoke English and had never before seen a test - he concluded that immigrants were of low intelligence and that immigration must be curtailed.

Richwine's methods are a bit more nuanced than those of Goddard and Broca, but just barely. Richwine makes a connection between the genetic makeup of Hispanics and their IQ. However, there is no genetic basis for racial differences. And "Hispanic" is an ethnic category including people of every racialised category possible. In the US, a Hispanic is a person with roots in Latin America. Their ancestry could include people from any continent. The claim that Hispanics share a genetic makeup that could differentiate them from white Americans is simply ludicrous.

Flaws in IQ-testing

Intelligence testing is also deeply flawed. Stephen Jay Gould points out that the primary error in intelligence-testing is that of reification - making intelligence into something by measuring it. It is common knowledge that some people know more facts and trivia than others, that some are quicker-witted than others, that some can calculate sums in their heads faster than others, and that some are more eloquent in speech and writing than others. Intelligence tests attempt to take this wide range of abilities and to measure them. The score on these tests is named an "intelligence quotient", or IQ. Gould contends that these tests are flawed and do not meet their stated goal of actually measuring intelligence.

To the extent that it is true that Hispanic immigrants score lower on these tests than white Americans, this is a result of unequal educational opportunities, not genetics. Diego von Vacano, a graduate of the Harvard's Kennedy School, points out that:

"the rudimentary statistical analysis of the kind that Richwine carried out ignores the important interface between social realities and genetics... [IQ scores] reflect the intertwining of some aspects of mental capacity with education, life experiences, socioeconomic status, and other contingent contexts."

Despite the fact that this perspective is widely accepted among scholars, Richwine chose to rely on the scientific racism tradition of his predecessors, and attributed the differences to genetics. This argument harkens back to the eugenics movement of the early 20th century, during which time about 60,000 people were forcibly sterilised in the US on the basis of their purported intellectual unfitness.

Despite this unfortunate history, ideas of innate inferiority and superiority are still advocated by a few, marginal pseudo-scientists. The hereditarian theory of intelligence, for example, continues to be perpetuated through the work of Richard Herrnstein and Charles Murray, authors of The Bell Curve (1995) - which Richwine liberally cites in his dissertation.

In 2004, Frank Miele, senior editor of Skeptic, and Vincent Sarich, professor emeritus of anthropology at Berkeley, argued in their book Race: The reality of human differences that races are a biological reality and that there are real, measurable intellectual differences between racial groups. Both The Bell Curve and Race: The reality of human differences trace their intellectual origins to early 20th-century eugenicists and endorse the idea that not only do biologically defined races exist, but that there are measurable differences between the innate mental abilities of racial groups. Jason Richwine joins this long and unfortunate tradition.

Similar to their predecessors, these writers find that their own group - Europeans - is intellectually superior to others. Both of these pseudoscientific books have been heavily critiqued by specialists. Esteemed race scholar Jonathan Marks, for example, signals the ludicrity of Miele and Sarich's finding that the average IQ of indigenous Africans is about 70, by pointing out that most native Africans probably speak more languages than Sarich and Miele combined and argues that their book is "scientifically idiosyncratic and politically reactionary".

Scientific racism

As an academic, I find it appalling that, in 2009, three professors at Harvard University were willing to sign off on a dissertation in this academic tradition. There are two central problems with Richwine's work that should not pass muster in any dissertation committee: first, the argument that IQ scores are an indication of intelligence; and second, the idea that IQ is a genetic trait. Both ideas have been discredited and both are linked to an unfortunate history of scientific racism.

The idea that IQ scores could be a reflection of a heritable trait is one of the pernicious ideas that led to the Holocaust as well as eugenics programmes in the US and elsewhere. Apart from its ugly history, scientists do not have a clear understanding of the extent to which intelligence may be a heritable trait. Even if some aspects of intelligence are based on heritable traits, there is no doubt that environmental factors shape one's ability to score highly on an intelligence test. Nevertheless, in his dissertation, Richwine eschews this evidence and argues that "the low average IQ of Hispanics is effectively permanent".

The pernicious nature of this dissertation points to the obvious question of who signed off on this dissertation. The answer, which is public information, is that George Borjas was the chair and Richard Zeckhauser and Christopher Jencks were the other two committee members.

These three scholars are getting flak for having signed off on this dissertation. This is as it should be. Scholars should get called out for condoning work that is fundamentally racist.

Before Jason Richwine began the work that was to be his dissertation, he would have had to consult with scholars in his department to ask them if they would be on his doctoral committee. At that point, they should have explained to him that this work carries on the tradition of scientific racism, and has no place in 21st-century scholarship.

It is clear that Richwine's dissertation is thin - with weak statistical analyses and a literature review that relies too heavily on racist and shoddy publications by Charles Murray, Richard Herrnstein and Philippe Rushton. But this dissertation should never have been written in the first place.

Tanya Golash-Boza is an Associate Professor of Sociology at the University of California, Merced. She is the author of Yo Soy Negro Blackness in Peru, Immigration Nation: Raids, Detentions and Deportations in Post-9/11 America and Due Process Denied: Detentions and Deportations in the United States. She blogs here.

Follow her on Twitter: @tanyagolashboza

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