Two things are infinite: the universe and human stupidity; and I'm not sure about the universe. -Albert Einstein
A word to the wise ain't necessary, it's the stupid ones who need the advice.-Bill Cosby
I am patient with stupidity but not with those who are proud of it. —Edith Sitwell
"There is more stupidity than hydrogen in the universe, and it has a longer shelf life." -Frank Zappa
The dumbest people I know are those who know it all.-Malcolm Forbes
Nothing in all the world is more dangerous than sincere ignorance and conscientious stupidity.-Martin Luther King Jr
Wise men talk because they have something to say; fools, because they have to say something.-Plato
To succeed in the world it is not enough to be stupid, you must also be well-mannered.-Voltaire