I said "morally acceptable," which is something not often considered when discussing intelligence in a human being. But I rather accept Lionel Trilling's contention that in a democracy, there is a moral obligation to be intelligent. One cannot control many factors that contribute to intelligence, of course, but one can read and struggle to become as intelligent as possible, given one's constraints.
But fiction--and here I'm going to throw in movies, literature, plays, and TV, since fiction in all of them operate off similar psychological principles--often encourages us to love stupid people. Carl Sagan was chagrined when Dumb and Dumber became the number one movie in America in 1994, but if he had lived into today, he'd have countless more examples to shake his head at.
Let's consider Andy Dwyer from Parks and Recreation. If you're not familiar with the show, this montage ought to give you a pretty good idea:
Even if you don't know the show, you probably know Andy, because "Andy" has been done to death in the last 20 years in American TV. I didn't even own a TV for five years once, but without trying, I can come up with: Phoebe from Friends, Kramer from Seinfeld, Peter Griffin and a few others from Family Guy, Homer Simpson from The Simpsons, half the town of South Park, Coach and his replacement Woody from Cheers, Luke Dunphy from Modern Family, Rose from Golden Girls, Malorie from Family Ties, and that's just what I can do without Googling.
Although the rise of the "goofball-hero" has been a characteristic of American TV of the last 25 years, it does have antecedents in literature. I'm not talking about characters who are dumb and evil, but characters who are dumb and also meant to earn the sympathies of the audience. Don Quixote leaps to mind. Although Cervantes himself apparently meant for Quixote to be much more scorned than he has ended up being, many readers throughout history have sympathized with the eponymous hero, with some interpretations such as the musical Man of La Mancha actually romanticizing him. Lenny from Mice and Men is another stupid character we are meant to root for, although Lenny appears to honestly not be able to help it, unlike many modern American goofball-heroes.
Characteristics of the goofball-hero
The goofball-hero makes claims on our sympathies because while he may not be bright in a traditional, bookish sense, he's a "good guy." He'd never scheme against you, in large part because he is incapable. He cannot even conceive of guile, or if he tries, it fails so badly, one doesn't hold it against him, because the attempt is so pathetic. In this sense, our attachment to the goofball-hero is much like our attachment to dogs.
The goofball-hero also often has a certain mystique of wisdom attached to his or her persona. Nine of ten statements the GH makes are meant to get a laugh because of how simple, foolish, or mistaken those statements are, but then every so often, the GH says something profound. This wisdom is assumed to be the product of a life unencumbered by all those book lernin' thoughts that weigh us down. By sacrificing traditional intelligence, the GH obtains an esoteric wisdom not available to the rest of us.
This was a device the writers of Friends resorted to often. The entirety of Chauncey Gardiner's character in Being There is built around the delivery of unintentionally thought-provoking aphorisms.
Not that there's anything especially wrong about it...
We all know people in life who just aren't that bright, but have good hearts and mean well. Even if everyone in America committed themselves tomorrow to bettering their minds, exactly 49% of the population would always be of below average intelligence, and not all of that 49% would be bad people. We'd want them on our sides in a tough spot, and indeed such people often are, maybe even more so than the smarties in our lives, because their brains don't give them reasons not to be there for us at a personal cost to them. I'm not talking about people with genuine developmental issues. I'm talking about people who just were never interested in school, people who don't read now, whose minds are both stubbornly made up in some ways and yet dangerously pliable in others.
One use of fiction is to make us see things through other perspectives, and it's certainly possible to see things from the perspective of the GH and appreciate that there is value in the life of a person who is not traditionally intelligent. On the other hand, if becoming intelligent is, indeed, a moral obligation, then the willful failure to do so must be immoral in some sense. But the entire thrust of the GH's depiction for the last several decades has been to ignore the immoral aspect of a lack of intelligence.
But there's definitely something wrong with the flip side of it...
Nowhere is this more easily seen than when we get a depiction of someone supposedly intelligent. The Big Bang Theory has been presenting intelligent people as hopelessly socially inept for over a decade now. Even while they are the protagonists, they are still the butt of the show's own jokes. Intelligence is seen as a condition one is born with, and it comes with a major downside one also cannot do anything about. It's the flipside of the GH: the GH also really can't do anything about the way he is, but there is also an upside to being born that way. Indeed, in Jonathan Franzen's novels, being born with advantages that lead to a developed intellect is almost certain to lead to crippling personality disorders.
All of this demonstrates the most radical kind of democratic view of things, in which nobody can really be critiqued, because we all just are the way we are. If nobody can be critiqued, nobody can be praised, either. This ends up with a worldview that skews slightly in the anti-intellectual direction, because the presence of someone who has become intelligent by his own bootstraps is an indictment of everyone who hasn't. So we have to mock the intelligent as pretentious and self-important.
This is actually as old as the very first American literature. The jock, Bram Bones, gets the better of the stuck-up prig school master Ichabod Crane, who wanted something in life above his station. So the jock pulls a practical joke on the nerd and chases him off, leaving room for the more likeable genes to be passed on. It's an archetype deeply ingrained in our cultural psyche.
This isn't necessarily an indictment of literature, but it's close
Of course, if literature can get us to accept one worldview, it can get us to accept another. There is nothing preventing me from using a story that demonstrates that being smarter really is better than remaining ignorant. But that's a hard sell. Buffoons do much better with audiences than smart people do. Using a fool to get around the prejudices of the audience and communicate some truth is a tried and true technique in Shakespeare, although Shakespeare's fool was never unintelligent, only iconoclastic. There is nothing especially wrong with tricking the audience by holding up a fool to laugh at, and then using those good feelings toward the fool to get the audience to accept a truth it would have resisted from someone else. But in the process, we seem to have come to love truly foolish types of fools, far more than might be good for us.