I read that book too. It is a bunch of baloney pushed by people who did a very poor job doing research.
Funny but when the three things I mentioned show up suddenly the IQ apparently soars. When they vanish the IQ drops. Amazing how that can happen in just few decades.
20 posted on 06/26/2019 8:30:53 AM PDT by Harmless Teddy Bear
(Human beings don't behave rationally. We rationalize our behavior.)