Beliefs deserve enough openness for a real event to teach them something.

A view held so firmly that nothing which happens can adjust it has stopped doing the work a view is for. It no longer tells you about the world, only about itself. Real events are the only teachers available, and they only reach a mind with some give in it. Keeping that give is not weakness of conviction, it is what keeps conviction honest.

Think of one thing you hold that you would defend even against what you saw with your own eyes. You do not have to abandon it. Just decide, now, what would count as being wrong about it.