–“DO SMART PEOPLE LACK COMMON SENSE?”–
Well, there are a couple of issues here we can discuss.
1) IQ increases the rate at which you learn, and the degrees of indirection between what’s learned.
2) IQ is the most dominant personality trait, with industriousness second, and all others comparatively far less influential.
3) By and large, after the age of 22, we effectively sort by IQ. Or at least every 1/2 standard deviation (7 points). And it applies (generally) to all walks of life.
4) People with average IQ’s tend to collect information from peers. People with high IQ’s rely less on the opinions of others.
5) So average people network more and pursue less risky, or novel (innovative) ends, and smarter people do the opposite.
6) This is why science has been so important because as we have learned science and reduce errors, the ‘habits’ of scientific thought have been adopted by mainstream people and they ‘calculate’ together fairly successfully.
7) My point of view, is that together we create a sufficiently homogenous set of habits that we believe we understand far more than we do – (overconfidence) – when all we are doing is habituating norms that survived evolution and markets.
8) Roughly speaking, 140 innovates, 130 explains 120’s apply, 110’s organize, 100’s do, 90’s follow, 80s do the best they can and are generally angry about it, and 70s stumble through life despite the fact that no matter what they do it seems not to work. That’s an exaggeration, but it’s close enough that it serves as a general rule of understanding. We are just as specialized as ants, but the similarity of emotion, want, and language convinces us that we are more similar than we are.
Hence why we generally choose every aspect of our lives so that we function with people within six degrees of separation.