By Bryan Caplan
There’s something very appealing about Arnold’s praise of thinkers who try to open readers’ minds instead of closing them:
Suppose we look at writing on issues where people tend to hold strong opinions that fit with their ideology. Such writing can
(a) attempt to open the minds of people on the opposite side as the author
(b) attempt to open minds of people on the same side as the author
(c) attempt to close minds of people on the same side as the author
So, think about it. Wouldn’t you classify most op-eds and blog posts as (c)? Isn’t that sort of pathetic?
Still, all this reminds me of an old saying: “Keep an open mind – but not so open that your brain falls out.” In economic jargon: The optimal level of openness is not infinite. When you’re more open, you’re less likely to dismiss truths, but more likely to accept falsehoods.
This isn’t just idle theory. Excessive openness is the root cause of many errors. Obvious examples include belief in astrology, alien abduction, various conspiracy theories, ghosts, the health benefits of organic food, and the long-run benefits of war. These beliefs persist largely because people are too reluctant to scoff, dismiss, or repeatedly say, “show me.”
The right mental stance for thinkers to promote – for both “their side” and the “opposite side” – is not openness, but judiciousness. Put your emotions aside. Use common sense. Look at the facts. Look for counter-evidence. Re-read Daniel Kahneman‘s Thinking, Fast and Slow. This is more difficult than promoting across-the-board “openness,” but well worth the extra effort.