Elon Musk Was the Shoeshine Boy

Who knows if it’s true or not, but there’s a quote frequently attributed to Joseph Kennedy that goes: “If shoeshine boys are giving stock tips, then it’s time to get out of the market.”

The intuition is pretty straightforward. Usually financial speculation and trading is done by professionals, and so by the time the trade idea has filtered out into the world so much that even the shoeshine boy is talking about it, that’s probably a sign of the top.

A couple of years ago, I wrote a piece for Businessweek about how, with certain modern bubbles and manias, the trajectory went exactly backwards. Instead of starting with elites and filtering down to the proverbial shoeshine boys, it was the shoeshine boys who got there first. The pros got there later. Here’s what I wrote at the time about Bitcoin: