My theory is that there is a finite amount of intelligence in a family, and you're supposed to gradually transfer it to your children over a period of many years. This is why your parents started to get so stupid just at the time in your life when you were getting really smart.
Dave Barry (1984). “Babies and Other Hazards of Sex: How to Make a Tiny Person in Only 9 Months, with Tools You Probably Have Around the Home”, p.72, Rodale
