Race science is back.

To be fair, it never really left. But in the past few years, an obsession over the intersection of race and science — and in particular, the use of science to shore up theories of racial hierarchies — has seen a resurgence. At the heart of this revival: Charles Murray, co-author of the notorious 1994 book on innate intelligence and public policy, “The Bell Curve.”

After being shouted down by protesters while trying to give a talk at Middlebury College last spring, Murray was invited to participate in a two-hour podcast conversation with Sam Harris, prominent new atheist and champion of science and so-called reason.

But, as Vox editor Ezra Klein pointed out, Murray’s views — especially his ideas on the heritability of intelligence, which Murray explicitly linked to race and which have been gleefully adopted by overt and covert white supremacists — are hardly the groundbreaking and new ideas that Harris presented them to be. Rather, they are very old and very bad ideas that have led to unspeakable oppression, particularly of black Americans.

But these ideas are even older than Klein realizes. To understand the underlying assumptions of Murray and others, it’s helpful to look back to the granddaddy of all racial theorists: Aristotle. In understanding the role Aristotle played in laying the groundwork for “race science,” we can better understand how ingrained it is in Western science and philosophy, and why the alt-right’s embrace of “western civilization” has a particularly chilling edge.

Most famous as a philosopher, Aristotle — who, it’s worth noting, is Murray’s favorite philosopher — was just as influential in what we would today consider the field of natural science. Indeed, Aristotle’s philosophical and political ideas cannot be separated from his methods of empirical observation. He spent years of his life observing and classifying animals. Charles Darwin himself said that “my two gods [Linnaeus and Cuvier] are mere school-boys to old Aristotle.”

Aristotle arrived at his biological taxonomy by observing and recording as many animals as he could, and he did likewise with types of government to arrive at his political taxonomies. Human beings, too, were subjected to Aristotle’s empirical analysis, as rigorous as any at least until the Scientific Revolution two millennia later.

In the first book of his “Politics,” written in the 300s B.C., Aristotle uses these taxonomies to justify the exclusion of certain people from civic life. While condemning the predominant method of acquiring slaves in his day — capturing prisoners in war — Aristotle argues that some people are by nature (rather than circumstances) fit to be slaves: “For that some should rule and others be ruled is a thing not only necessary, but expedient; from the hour of their birth, some are marked out for subjection, others for rule.” Not only were some people slaves by nature, but it was clear that, for them, “slavery is both expedient and right,” he wrote.

That Aristotle espoused these views matters, because his imprimatur imbues them with authority and an air of dispassionate reason. Many readers of the “Politics” have concluded that Aristotle lays out first principles, the indisputable facts prescribed by nature, before reasoning from them to arrive at his political theories. If nature, including hierarchies and natural slavery, is simply a fact, then society can function properly only if it is ordered with this fact in mind.

Facts don’t care about feelings, after all. Aristotle therefore envisioned a hierarchical society, where everyone had their proper place, from fully enfranchised citizens all the way down to slaves. Given how nature has endowed different people differently, such a society would benefit all.

Anyone familiar with the arguments in “The Bell Curve” can probably already sense the ways Aristotle’s naturalistic fatalism connects to today’s “racial science.” Given the results of IQ tests, on which aggregate black Americans fare more poorly than white Americans — a result which Murray contends is at least in part due to genetics — social policies to improve the prospects of marginalized groups are bound to fail unless they take into account these hard, scientific facts. Most Great Society programs fail on that metric, according to Murray.

Thus he proposes that welfare and other financial supports for poor mothers should be eliminated because they serve only as incentives for the wrong people to reproduce. “The Bell Curve” argues that “the most efficient way to raise the IQ of a society is for smarter women to have higher birth rates than duller women.”

Murray also says that there should be “a place for everyone,” that a return to traditional values and traditional neighborhoods would allow space for even “low-IQ individuals” to find the types of jobs and stable marriages in which they can lead fulfilling lives, while contributing to society as a whole. This is a dressed-up rehashing of the very same ideas Aristotle seems to have championed: that nature is immutable and that society works best when everyone is assigned their proper place according to their natural abilities.

But the theories of Murray and Aristotle have one massive flaw. Their ideas about natural hierarchies, particularly those delineated by race, have been regularly refuted. Libraries are filled with works by experts challenging the scientific validity of “race science.” The fatalism of Murray and others has been critiqued because it absolves us from addressing or even acknowledging the structures and attitudes that lead to and sustain racial and other oppressions.

Nor are the critiques limited to Murray and his contemporaries. As many scholars have pointed out, Aristotle’s position is self-contradictory. While he argued that natural slavishness is due to an inborn deficiency in the capacity to reason, in Aristotle’s formulation, having the capacity to reason simply is the defining characteristic of being human in the first place. How, then, can there be natural slaves?

The answer might lie in the idea that Aristotle was not as staunch a proponent of race science as is generally thought. Political theorist Jill Frank suggests that he was well aware of this apparent contradiction, and throughout his body of work aimed to frame politics not as a function of nature, but rather nature as a question for politics. That is, rather than setting the immutable standards for politics, a person’s innate capacity — his or her fitness for political engagement — itself can be changed and shaped by the very act of political participation.

Because it is impossible to distinguish natural slaves from natural rulers based on external factors such as physical appearance (as indeed it is impossible to assess people’s IQs based on their membership in a given group), it is the activities in which an individual engages that determine one’s nature. Aristotle leaves room for the possibility that habitual engagement with activities appropriate for a free person can make one, in fact, take on the nature of a free person. As Frank concludes, “nature thus distinguishes slaves from nonslaves but secures no absolute boundaries and offers no permanent foundations. Guided and determined by activity, nature is changeable.”

Klein identifies the core problem with the position of Murray and his supporters, who hide behind the supposed cold, hard fact of differences in IQ, in their denial of the historical, cultural and social conditions that underlie these realities: “You cannot discuss this topic without discussing its toxic past and the way that shapes our present.” Aristotle might well agree with Klein. Context matters, and it is the role of politics to establish that context. Instead of discouraging low-IQ individuals from having children or paternalistically assigning them to their “proper place,” as Murray advocates, let’s work on identifying and rectifying the contexts that lead to low scores on IQ tests in the first place.