It seems that GRE takers intending to major in Philosophy have the highest scores in two of the three tested areas verbal reasoning and analytical writing. Of course physics and astronomy majors dominate the mathematical reasoning and also do quite well in the other two, but how do we explain why so many modern philosophers turn out to be dumb asses? I have a theory: the smart ones usually decide to do something more worthwhile while those who go on to tenured positions get frustrated when they figure out that they really aren't equipped to understand anything important.
I found an example in this book about the Nobel prize winning work of Daniel Kahneman and Amos Tversky on the kinds of mental errors all people commonly make:
At a conference back in the early 1970s, Danny was introduced to a prominent philosopher named Max Black and tried to explain to the great man his work with Amos. “I’m not interested in the psychology of stupid people,” said Black, and walked away. Danny and Amos didn’t think of their work as the psychology of stupid people. Their very first experiments, dramatizing the weakness of people’s statistical intuitions, had been conducted on professional statisticians. For every simple problem that fooled undergraduates, they could come up with a more complicated version to fool professors.
Lewis, Michael. The Undoing Project: A Friendship That Changed Our Minds (Kindle Locations 4348-4351). W. W. Norton & Company. Kindle Edition.
Black was wise to flee, since if he had hung around Tversky would likely have quickly demonstrated that Black, like the others, was in fact one of those stupid people. If you've invested your whole psyche in believing you are smart, it can be cheaper just to be an asshole than face that fact.