Charlie Munger is a smart smart man.
Well, you can laugh at that. It is ridiculous but it's no more ridiculous than the way a lot of people cling to failed ideas. Keynes said "It's not bringing in the new ideas that's so hard. It's getting rid of the old ones." And Einstein said it better, attributing his mental success to "curiosity, concentration, perseverance and self-criticism." By self-criticism he meant becoming good at destroying your own best-loved and hardest-won ideas. If you can get really good at destroying your own wrong ideas, that is a great gift.
Destroying your own best-loved ideas is hard, but whether you are an individual or a company, it's the best way to grown and change over time.