People are not unitelligent if there ignorant to a specific subject unknowingly, they just don't know any better.
If someone knows their wrong and chooses to be ignorant their not uninteligent, their assholes.
If someone is just plain ignorant towards everything, their dumbasses.
Ignorance dose not flow with intellegence, it simply means someone has inadequate/uncorrect information on a subject yet talks of it as the truth, or openly chooses to believe a lie. It's another way of calling a person hard-headed as well.