Newcomb’s Paradox

Flamdor McSqueem is a superintelligent wombat from the planet Zortag. He shows you two boxes. You can choose to take the contents of Box A or the contents of both boxes. He has privately predicted what you will do.

If Flamdor predicted you would choose Box A only, then Box A contains $1 million. If he predicted you’d choose both boxes, then Box A contains nothing. Either way, Box B contains $1,000. What should you do?

Some people reason that Flamdor is very intelligent and his predictions are usually accurate, so it would seem best to choose Box A. Others note that Flamdor has already made his prediction and can’t change the contents of the boxes now, so it seems best to take both boxes.

There’s no correct answer — decision theorists are still arguing about it. What would you do?