I don't know how to put this but I'm kind of a big deal.

"The fundamental cause of trouble in the world today is that the stupid are cocksure while the intelligent are full of doubt." -- Bertrand Russell, via Julian Sanchez

See also Fred Kaplan ("The fact is, Giuliani has no idea what he's talking about."), Kevin Drum ("Hmmm. That reminds me of somebody. But who? Push? Tush? Schmush? Something like that....."), and the Dunning-Kruger Effect ("The Dunning-Kruger effect is the phenomenon whereby people who have little knowledge systematically think that they know more than others who have much more knowledge.").