Thomas Sowell is no ordinary right-wing pundit. For one thing, he is actually a subject expert, having a Ph.D. in economics from the University of Chicago. For another, he has won many honors off limits to hacks. From a National Humanities Medal to positions at Cornell and UCLA, he is among the most decorated of conservative intellectuals writing today. Harvard psychologist Steven Pinker cites Sowell approvingly, and he has been praised by The Economist. Among conservatives, Sowell is akin to what John Kenneth Galbraith was for the left, a hallowed figure approaching the status of a deity.

Sowell’s most esteemed work is A Conflict of Visions: Ideological Origins of Political Struggles. In 2005, National Review cited it as one of ten books that have “advanced the cause of conservatism, and of freedom in general” in the magazine’s lifetime, alongside classics by Solzhenitsyn and Milton Friedman. Scholar Charles Murray wrote that A Conflict of Visions “gives us an intellectual framework that must shape an attentive reader’s way of looking at the political world forever after.” Upon the book’s initial release in 1987 (a revised edition appeared 20 years later), the New York Times called it “cogent” and “extraordinary.”

The 25th anniversary of the book makes an apt occasion for reconsidering A Conflict of Visions. For while Sowell’s work has the trappings of a dispassionate, fair-minded rendering of political debates, in fact it exemplifies many of the failings common to the contemporary conservative intelligentsia. Not only does the book fail to understand the American left, it fails to describe the American right from which Sowell himself emerges. For all its erudition and accessibility, A Conflict of Visions betrays a profound self-delusion.

According to Sowell, American political debates follow two parallel lines tracking distinct visions of human nature. Those on the left have an unconstrained view of man, and those on the right have a constrained view. The unconstrained view holds that humans are perfectible creatures sullied only by their flawed social environments. With the proper education and social support, man can become an altruistic, even Christ-like being. Enlightenment philosopher Jean-Jacques Rousseau was the unconstrained thinker par excellence, holding that “men are not naturally enemies” and that the individual “is born free but everywhere is in chains.” Man is inherently rational in this perspective. With proper organization and education, universal peace is attainable, as is the eradication of poverty, violence, and disunion. John Kenneth Galbraith was a recent example of a thinker with an unconstrained view of human nature, according to Sowell.

In contrast, the constrained vision sees man as a beast, held in check by customs, traditions, and coercion. Adam Smith, the Federalist, and, especially, Edmund Burke epitomized the beliefs of the constrained view. Moral and intellectual limitations define the perspective of this outlook, which believes above all in the “general infirmities of human nature,” as Burke put it. War is ineradicable, as are class conflicts, hatred, and evil. The ideas of Friedrich Hayek represent the humility of the constrained view, writes Sowell.

For Sowell, these taxonomies go far in explaining political debates. “Conflicts of visions affect not only such large and enduring issues as economic planning versus laissez-faire, or judicial activism versus judicial restraint, but also such new issues as the most effective modes of Third World development, ‘affirmative action,’ or ‘comparable worth,’” he writes. “In each of these controversies, the assumptions of one vision lead logically to opposite conclusions from those of the other.”

Even-handed as Sowell’s arrangements appear to be, they are deeply flawed. For all his purported commitment to evidence, very little of contemporary debate is explained by Sowell’s visions. Begin, for example, with foreign policy. Only those who call themselves paleoconservatives or foreign-policy realists can be honestly considered adherents to the constrained view of human nature in international affairs. In recent years both liberals and movement conservatives have shown themselves fond of nation-building and using force to change foreign societies. It would be difficult to imagine a policy matching the unconstrained vision more perfectly than the invasion and occupation of Iraq, with its intention of swiftly implanting liberal-democratic values in a region that has scarcely known them. Given his self-conception as the prudent man facing a society of overzealous social engineers, one might be surprised that Sowell, like nearly all other Republicans, supported the war. More than that, he criticized the very idea of a constrained foreign-policy vision. In a 2002 column called “Dangerous Restraint,” he likened the “threat” from Saddam Hussein to—what else?—that of Adolf Hitler in the 1930s. “Caution is sometimes the most dangerous policy,” he wrote. “And this looks like one of those times today.”

By 2006, Sowell was suddenly re-embracing the constrained view. “Another concept whose bitter falsity has been painfully revealed in Iraq is ‘nation-building.’ People are not building blocks, however much some may flatter themselves that they can arrange their fellow human beings’ lives the way you can arrange pieces on a chess board.” Like so many other contemporary intellectuals, Sowell does not so much subscribe to a political philosophy as adopt and abandon ideas whenever convenient to do so from a partisan standpoint.

This is not just a matter of scoring cheap shots or identifying obvious examples of hypocrisy. The point is that today’s debates don’t primarily revolve around notions of human nature. Those who oppose same-sex marriage, for instance, are nearly all self-described conservatives—among them Thomas Sowell. Yet one would be hard-pressed to imagine a more radical unconstrained vision than the hope that an individual’s homosexuality can be reversed. “What the activists really want is the stamp of acceptance on homosexuality, as a means of spreading that lifestyle, which has become a death style in the era of AIDS,” Sowell wrote in 2005. The notion that homosexuality can be spread to those who don’t want it reveals a tremendously malleable view of human nature.

Similarly with healthcare. Those on the left who believe in universal healthcare have plenty of other countries to point to as examples of places where human nature is sufficiently elastic to allow for government-sponsored health services. Conservatives do not oppose government-run healthcare out of a belief that humans are incapable of it. Rather, they do so on the principle of individual responsibility and beliefs about the proper role of government. Human nature enters into it little, if at all.

On issue after issue, what Sowell sees as debates reflecting conflicting visions of human nature revolve as much or more around concepts such as justice, freedom, and religion, to say nothing of the grubbier instincts of class, race, and tribe. To the extent that A Conflict of Visions has become a lodestar for the right, it suggests nothing so much as a lack of self-understanding. Sometimes even the strongest of visions are blurred.

Jordan Michael Smith is a contributing writer at Salon.