Mark Thornton

Skyscrapers inspire.

Sometimes they inspire shudders.

I am an admirer of such neo-Babels, and you can’t find a better Schelling point for New York than the Empire State Building. Civilization’s highest erections symbolize something good about humanity.

And yet, I wonder about the latest Chinese engineering effort, Sky City, to be built in Changsha in record time, 90 days.

It’s supposed to house over 31,000 people, contain hotels and restaurants and schools and shops, too, and tower up 163 floors to a height of 2,749 feet.

How could such a thing be so quickly constructed, and still be safe?

Cheating.

Well, not really. It’s prefab. Much of the work has already been done. Building it will be a job of putting pre-fabricated pieces together. The company responsible for the effort has had some success on prefab buildings before, and . . .

The whole thing still sounds a tad hubristic. I wish the builders (and inhabitants) the best, but, even if it succeeds, there’s an ominous aspect to the whole project, if economist Mark Thornton’s theory about new-building skyscrapers has any truth to it. Tall buildings are built when people are optimistic. People are most optimistic during booms. Booms — at least inflationary booms — yield to busts, and many of the major economic depressions have been marked by unfinished or just-finished record-book skyscraper projects.

Does Sky City signal a Chinese bust coming soon?

It may. For the story of our time might be this: China is to America, now, what America was to Great Britain in the 1920s and ’30s. Similar monetary policies and bailouts.

And the loaning nation doesn’t get off free. At least, we didn’t in the decade in which the Empire State Building was finished.

This is Common Sense. I’m Paul Jacob.

Many Americans who have never driven in ol’ London town have driven over the London Bridge — in Arizona. I’m an outlier, here, in that I’ve been over many a London bridge, but not to Lake Havasu’s.

But that doesn’t make me an expert on the Shard London Bridge, a London skyscraper (yes, skyscraper) nearing completion. Popularly called “The Shard,” it will be the tallest building in Europe.

So prepare yourself: Expect a major economic collapse in the old country.

Yes, for the last century, the building of record-height skyscrapers could have served as a leading economic indicator . . . of disaster. As Mark Thornton explains, record-setting skyscraper construction is

a sign of a looming economic crisis. The model has successfully identified the Panic of 1907, the Great Depression, the Stagflation of the 1970s, the Tech Bubble, and the Housing Bubble.

In a scholarly paper on the subject, Thornton cautions not to use this strange correlation “as a guide to fiscal and monetary policy” or, superstitiously, an excuse to regulate “skyscraper heights . . . to prevent economic crisis.”

But the connection between building heights and boom-and-bust remains suggestive. Extra-big skyscrapers rise during extra-big booms, themselves fueled by central bank credit inflation. That is, inflation — and its usual consequences (which include unexpected deflation and financial collapse).

If only our central banks could maintain a stable money supply, rather than constantly tinkering with money to fine-tune the economy, our biggest buildings might not serve as such good predictors of our biggest economic downturns.

This is Common Sense. I’m Paul Jacob.