Shine a flashlight in their eyes
 

Unfortunately, hang around usenet groups long enough and one is inclined to
belief that compulsory universal education for the masses is a wrong thing.
way too many people unable to walk and fart at the same time are taught to read
English and kinda write it. these stop-walkers come believe they therefore
understand the totality of the universe. But the truth be known, for most of
them if one shines in a flashlight in their eyes you will see the backs of
their skulls.

History will judge usenet groups, probably, as it does members of the John
Birch Society. Too dumb to come in out of the rain, too smart to raid garbage
cans for food.