"it is better to keep silent and be thought a fool than to speak and remove all doubt" A.Lincoln, I believe.It is much older than Lincoln, according to Bartlett's:
Publius Syrus (42 B.C.) Maxim 914. "Let a fool hold his tongue and he will pass for a sage."
Another Publius Syrus maxim I like: "Fortune is not satisfied with inflicting one calamity." - Maxim 274. When it rains, it pours?
Liberals and communists never get it...now their islamic sympathies are drowning them too!
I was referring to a specific formulation... the notion expressed is probably only slightly more novel than the advent of speech itself ;)