When the facts change

According to David Perkins of Harvard University, the brighter people are, the more deftly they can conjure up post-hoc justifications for arguments that back their own side. Brainboxes are as likely as anyone else to ignore facts which support their foes. John Maynard Keynes, a (famously intelligent) British economist, is said to have asked someone: “When the facts change, I change my mind. What do you do, sir?” If they were honest, most would reply: “I stick to my guns.”

from The Economist