Last week, I introduced a column by citing Stein’s Law. It holds: “If something cannot go on forever, it will stop.” Stein was Herbert Stein (1916-1999), an economist who had taught at the University of Virginia, served as the chairman of President Nixon’s Council of Economic Advisers and was a frequent economic essayist. I felt comfortable using the quote, because I knew Stein slightly, and not only was Stein’s Law widely cited but it also sounded like him. He was an excellent writer, had a wry sense of humor and possessed a talent for the pithy phrase.

But the next morning, I got an e-mail from an old friend — a first-class reporter — who wondered if the quote was legit. “A couple of years ago, I searched for the source of this gem and gave up,” he wrote. “I found a lot of people saying that Herb Stein had said this, but I found no quotation in Stein’s own words. Do you know the original source?”

I didn’t.

This was a polite way of asking: Were you snookered? One peril of the Internet is that it confers authenticity on the fake. Quotes and facts get repeated so often that they are accepted as genuine even when they’re not. If you Google “Stein’s Law,” some 460,000 results pop up. Many other Steins get mixed with Herb, but at least in the first few pages, there was no original reference for Stein’s Law.

Hmm. Looking bad.

At this point, I resorted to an old reporting trick: Get someone else to do your work.

I called the American Enterprise Institute, a conservative Washington think tank, where Stein spent many years. If Stein had authored Stein’s Law, I suspected it first appeared in a monthly publication — since discontinued — called “The AEI Economist,” which was typically a four- to eight-page essay on current issues. Unfortunately, these had not been digitized. Might someone check the originals?

The someone turned out to be Rebecca Wescott, an intern who waded through a decade’s worth of “AEI Economists.” Stein’s Law appeared on Page One of the June 1989 issue under the headline “Problems and Not-Problems of the American Economy.” The reference was inspired by America’s trade and budget deficits, which have probably lasted longer than Stein imagined likely.

In any case: Thanks, Rebecca.

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