On business TV, lower prices justify almost anything.

I’ll give Wal-Mart (WMT) credit for this much: Its new ad campaign has certainly got people talking. Some of the ads have a saccharine story line with people kissing on buses and such, but here’s a stripped-down version that highlights the central claim: Wal-Mart saves the average American family $3,100 a year. If, like me, you live nowhere near a Wal-Mart, you might let such figures wash over you, but the company insists that it’s true no matter where you shop.

It is possible to back up Wal-Mart’s claim, but only by retreating into very, very abstract ideas about the economy. So abstract that, while we were discussing this topic on CNBC last week, at least one CNBC anchor—Dennis Kneale—said that he would be in favor of slavery as long as it would lower prices. I can believe that Kneale got caught up in the heat of the argument—his follow-up response is below—but at a minimum this tells you about the sorry intellectual state of debate on cable television.

Let’s start by looking at Wal-Mart’s claim. Beginning in 2005, Wal-Mart commissioned the research firm Global Insight to produce a report measuring the impact of Wal-Mart on the overall American economy. Its methodology is, of course, open to debate, but the study tested 26 markets and measured the impact of a variety of economic factors on prices, going back to 1985. Not surprisingly, the study found that the widespread existence of Wal-Mart dating back to 1985 has resulted in about a 3 percent reduction of prices (3.6 percent in the most recent study, which is where the $3,100 figure comes from).

I don’t reject that finding. But it doesn’t mean that Wal-Mart is the only, or even the largest, economic force responsible for lower prices. As you would guess, the study also measured the impact on prices of many things that have little to do with Wal-Mart: energy costs, population growth, and unemployment. As I read the study, those factors combined are responsible for 89 percent of price variation. Wal-Mart and other factors are crumbs by comparison.

And so if you believe that Wal-Mart’s lowering of prices is “good for the economy”—that’s how CNBC framed the discussion on Wednesday—it follows that the much larger downward pressures on prices are even better. Unemployment, in particular, seems to be very good at lowering prices. So if we like prices when 10 percent of Americans aren’t working, we would love them if 25 percent of Americans weren’t working! Clearly there is a problem with this line of thinking, and I think it’s evident to a junior high-school student: Lower prices are helpful to consumers, but they are only one piece of a larger economic pie. They are not, in and of themselves, the only economic good, and indeed if prices get too low—at Wal-Mart or anywhere else—it almost certainly means that something else is out of whack. (In Wal-Mart’s case, infamously low wages, perhaps, but that’s another article.)

But that’s not how they see it at CNBC. I cringe to provide a link to the segment, but here it is. My fellow guest was a business professor from the University of Michigan, who has advocated that Wal-Mart should be given the Nobel Peace Prize. I tried to argue that it’s strange to say that anything that lowers prices is intrinsically good. Kneale interrupted me with the comment “It is!”

Well, if unemployment is good, then slave labor is better, right? If Wal-Mart could lower its labor costs to zero, imagine how rock-bottom its prices could be. I asked Kneale: “If [a $35] DVD player is produced by slave labor in China, is that a good thing?” His reply: “Yeah, it’s a real good thing, if I can buy it for $35.”

It seemed hard to believe that someone would actually say this on television. I followed up today by e-mailing CNBC’s PR department, which sent me this response from Kneale: “Of course I would never endorse slavery.  I was saying lower prices are always good and that no supplier cuts prices below what they can support.  I believe jobs in China that supply U.S. companies likely pay far better than many local jobs in the Chinese economy; and that globalization and free trade have lifted hundreds of millions of people out of poverty in the developing world. In fact, by 2012 almost a billion people across Southeast Asia will triple their per-capita income to join a new middle class. That is due to supplying companies like Walmart.”

This at least approaches a coherent position, and might have made an enlightening discussion. But on camera, CNBC anchors wanted to attack me for mentioning slave labor at all. Wal-Mart has admirably backed away from its worst practices in the Third World. But for the history, I refer everyone to Chapter 6 of Nelson Lichtenstein’s masterful book The Retail Revolution: How Wal-Mart Created a Brave New World of Business (which, at least for me, makes that Nobel Peace Prize idea a little far-fetched).

I know that live television can make people say stupid, provocative things that they don’t necessarily believe. Almost a year ago, Marion Maneker noted that CNBC has chosen to incorporate the production values of professional wrestling in order to hold viewers’ interest. And, as in professional wrestling, the notion of a fair fight is a thin veneer. But when its anchors start saying that low prices justify slavery, well … it actually increases my respect for professional wrestlers. That they don’t seem to believe such things is reassuring to a point, but still leaves the question: Why do viewers have to tolerate this? Why can’t CNBC act like its audience wants something more than mindless shouting?