Not necessarily. If I am an academic whose research is undermined by bias, I may be irrational but not stupid, and if I am in a social environment where certain signals of stupid beliefs are advantageous, I may be stupid but not irrational. It seems to be the latter is more what the author is getting at.
I feel like you should have said “irrational” instead of “stupid.” It would sound less funny, but it would be more accurate.
Not necessarily. If I am an academic whose research is undermined by bias, I may be irrational but not stupid, and if I am in a social environment where certain signals of stupid beliefs are advantageous, I may be stupid but not irrational. It seems to be the latter is more what the author is getting at.