I think "stupid" may be overstating it a bit. I think it's more that people only have a limited mental bandwidth and can only focus on a limited amount of cate

I think "stupid" may be overstating it a bit. I think it's more that people only have a limited mental bandwidth and can only focus on a limited amount of categories of life. Person A may think person B is stupid for not caring about the quality of background music. But person B might think person A is stupid for ordering a $5 glass of the house wine at a restaurant instead of some special French vintage. And person C might be aghast that that both A and B have standard factory tires on their cars instead of high performance low-profile racing tires.