You have to be careful, I've come to realize.  Once in a hotel in New York, I met this receptionist who was just... mindbogglingly dense. You have one of those conversations where you really think the universe is sort of bending around you, it's so stupid.
     -- Douglas Adams

Never attribute to malice that which can be adequately explained by stupidity.
-- anonymous

Only two things are infinite; the universe and human stupidity, and I'm not sure of the former.
-- Albert Einstein

No drug, not even alcohol, causes the fundamental ills of society. If we're looking for the source of our troubles, we shouldn't test people for drugs, we should test them for stupidity, ignorance, greed, and love of power.
-- P.J. O'Rourke

Ordinarily, he was insane, but he had lucid moments when he was merely stupid.
-- Heinrich Heine

Never underestimate the power of stupid people in large groups.
-- Idiocy, www.despair.com