Somebody made the decision that there were important things to know. I don't know how these important things to know were determined: by a single person, by a tribunal, by happenstance. I can't call it, but there was a subset (or superset) of facts and information or even abstract understanding that was picked out of all things that are knowable and called "vital". The esoteric nature of the emergence of this group of datum is still a mystery to me, perhaps someone's put the origins in a book that I haven't read, which is entirely possible. One thing is certain: if you were/are in relative possession of a mastery of this set of information, you are deemed intelligent. I know a lot of people who are deemed intelligent by the people that deem other people intelligent, themselves deemed by others as intelligent. This declaration comes in the form of citations, diplomas, degrees, advanced degrees, etc. The people I know who are deemed intelligent go on to identify other people of worthy education intelligent. The cycle continues....
My basic understanding, though, is that the information that is used to deem one intelligent is a circumstance of culture, societal norms, and an collective acknowledgment that a person has a sufficient knowledge of the generally acknowledged subset (or superset) of information available. I hear the words intellectual, savant, genius and shit like that bandied about in certain circles, words that are used to imply that the speaker has the gravitas to bestow such designation upon others, giving both the designator and the designated props. If I call Walter Mosley or Spike Lee a genius, I'm taking a little for myself for being able to recognize genius therefore inviting myself to that little party.
I'm saying all that to say this: I don't fucking know anymore. I don't like being a part of this game. If someone says or writes something and I recognize the reference or find a deeper meaning in it, then who the fuck am I to say that they're intelligent? Maybe they're writing down to me. Who knows. What I do know is that the dominant culture makes those rules, period. They dismiss ghetto dwellers and trailer park residents as being "ignorant", but people are playing by entirely different sets of rules than the "mainstream". Is it intelligent if a person from a different cultural understanding to try to go reason with a hostile person if from the "hood" person's observation of similar circumstances and symbolic identifiers tell him the only way to deal with that person is through violent measures? Viewing every situation through one cultural prism distorts the true nature of intelligence. When I say I've seen what I've thought to be true geniuses in the "hood", I'm not trying to be condescending or take any credit for myself for that recognition. People do what I could never do and what I'd never think to do. I'm in awe of it and I refuse to let cultural bias color that.
Intelligence is everywhere. It is nuanced and not concrete.