The Paralysis of Polarized Thought

There's a thoughtful essay in today's South China Morning Post that touches on the trap that snares polarized societies. 

It begins with a passage attributed to John Maynard Keynes:

"When my information changes, I change my mind. What do you do sir?"

It’s a good rule for people to follow in life. Unfortunately, I don’t always – because it’s actually very hard to. Often, I just block out new or contrary information and points of view I don’t like or share, without even thinking about it.

But if more people at least try to follow Keynes’ rule, there may be much less fanaticism and dogmatism in the world, whether in religion or even in science and academia, perhaps especially in university today.

But in the end, we all live in our own Matrix or Plato’s cave. The sunlight of truth outside is just too bright for me. It’s far more comforting to stay in the shade inside.

Keynes’ rule has its equivalent in statistics. It’s called Bayes’ rule or theorem. Thomas Bayes, an 18th century philosopher and Presbyterian minister, thinks you can strengthen your belief in something – increasing your “epistemic confidence” – by updating new information to your initial probabilistic belief that something is true or has happened. As a good Christian, he might have been motivated to develop the idea to defend the truth of miracles based on Biblical testimony against David Hume.

“Epistemic confidence” – towards which Bayes’ rule is supposed to move you – is the opposite of what the contemporary philosopher Gillian Russell has called “epistemic viciousness”, our inclination to hold false beliefs, despite new evidence or updated information. The latter is a natural human tendency; the former, though, takes serious mental discipline.

Bayes and Keynes tell us how to update previous beliefs in light of new evidence and in terms of probability. But their rules – whether quantitatively or qualitatively – can’t tell us what such beliefs to hold.

Say, you are a national security official in Washington and your previous belief is that most cyberattacks are carried out by state actors like China and Russia. This hypothesis could be tested in terms of Bayes’ theorem with new evidence. But suppose you are really committed to the hypothesis, like those who believed in the existence of weapons of mass destruction before the US invasion of Iraq, nothing will ever change your mind.

The columnist, Alex Lo, cites Hong Kong as an example where a society is so deeply polarized that neither side will allow nothing new to change their outlook. Isn't that what we're nervously watching occur in the States today, an impulsive tendency to reject information that contradicts dogmatic belief?

Maybe it's time we all became a little more Keynesian in our outlook. I know, I know, them first. Of course.