> Is a path of learning more and more about less and less

...until you know absolutely everything about absolutely nothing.

Nah, I forgot which top flight physicist (Nobel, I think) wrote in a book that he had explained to his mother that there were indeed very dumb PhDs, thanks to mere "sitzfleisch".

Most anyone in the business knows cases.

Smarter than average, for sure. But people tend to over estimate the intelligence of the average PhD.

It is not. The purpose of a PHD is to advance the sphere of human knowledge as it applies to a subset of existing data in a unique way. Getting the PHD by proving something empirically is the point of a PHD. This does not require a great deal of intelligence. Not enough to warrant more than a participation badge, anyway. e.g. Computer Science, where there's tons of data and few people have done the grunt work of organizing it for a statistician.

What those who contradict you above fail to appreciate is just how little IQ difference makes someone seem "dumb". Most people with 140 IQs rarely spend any time having discussion of any depth with anyone who has an IQ below 120. They have not the slightest idea how dense someone with an IQ of 100 seems. When I was training as a physician I routinely needed to explain important things in depth to people with average and below average intelligence. It is shocking. Most of us live in a narrow world and make poor assumptions about life outside