Only two things are infinite, the universe and human stupidity, and I'm not sure about the former.
There is a limit to human intelligence, but there is no limit to human stupidity
It seems to me certain that more people are killed out of righteous stupidity than out of wickedness.
Never attribute to malice what can be adequately explained by stupidity.
I'm not a complete idiot, some parts are missing.
The only difference between genius and stupidity is that genius has its limits.
Better to remain silent and be thought a fool, than to speak and remove all doubt.
IDIOT: A member of a large and powerful tribe whose influence in human affairs has always been dominant and controlling.
Never argue with idiots... They bring you down to their level and beat you with experience.
The trouble with the world is that the stupid are cocksure and the intelligent are full of doubt.
Gli idioti sono una saggia istituzione della natura che permette agli stupidi di ritenersi intelligenti.
A stupid man's report of what a clever man says can never be accurate, because he unconsciously translates what he hears into something he can understand.
I don't know what makes you so dumb, but it works!
With stupidity and sound digestion man may front much.
It's easier to fool people than to convince them that they have been fooled.
We always underestimate the ingenuity of idiots.