Wanting an original joke from an economist is a lot to ask for.

SimpleStacker

Here's a joke about the Efficient Markets Hypothesis:

Two economists, Milton and Murray are walking down the street. Murray says to Milton "Hey look, a $50 bill." Milton responds "That's impossible. If there were $50 just sitting on the street someone would have picked it up."

oracle

Prediction markets: can betting be good for the world? (2021)

Here's a joke about the Efficient Markets Hypothesis:

Two economists, Milton and Murray are walking down the street. Murray says to Milton "Hey look, a $50 bill." Milton responds "That's impossible. If there were $50 just sitting on the street someone would have picked it up."