When Lambo?

It was around the peak of bitcoin’s value a year ago at just below $20,000 that this obnoxious question entered the Urban Dictionary: How long would it take to amass enough cryptowealth to buy a Lamborghini? Now, those bitcoin owners still holding on for dear life after an 82% decline are putting on a brave face, but there is no more denying that we have witnessed the popping of a classic bubble.

Some believers in blockchain’s vast potential agree and rue the gold-rush mentality. Others are in denial, characterizing the current rout as just another bump in the road for a transformative technology. They point to multiple parabolic peaks and valleys over the years and actually have—or rather had—a point.

A speculative craze isn’t defined by its frequency or even its amplitude, which makes defining a bubble tricky. When bitcoin had appreciated by more than 1 million percent, an expert in manias said it didn’t meet his criteria for a bubble. Months later, bitcoin finally ticked nearly all of his boxes.

Harvard University lecturer Vikram Mansharamani, author of “Boombustology: Spotting Financial Bubbles Before They Burst,” put his money where his mouth was.