This comment by Arthur Schopenhauer raises some interesting questions:

If a person is stupid, we excuse him by saying that he cannot help it; but if we attempted to excuse in precisely the same way the person who is bad, we should be laughed at.  And yet the one quality, like the other, is inborn.   This proves that the will is the man proper, the intellect the mere tool.

While one can question any of these three claims, there is a real issue here that cannot be easily dismissed.  Thus I do not think being bad is entirely inborn, but then neither is being stupid.  Academic education is possible, and moral education is also possible.  With some effort, we can get smarter and we can get better. I doubt that any modest difference in the extent to which stupidity and badness are inborn can fully explain society’s vastly different attitude toward these two traits. And Schopenhauer’s conclusion about “the will” being the man proper leads one to ask:  Why are people viewed this way?

One possibility is that the harm from stupidity is usually internalized to a much greater extent than the harm from being bad.  We blame people for being bad because bad behavior has much greater external costs than stupid behavior.  A person can stupidly throw away a fortune at a casino with very little in the way of legal or moral sanction.  But if someone uses fraud to steal a fortune from another person, we call them evil and throw them in prison.  Stupid behavior causes harm, but much of the harm (not all) falls on the person that engages in the foolish actions.  If we consider both blame and prison to be forms of deterrence, then these sanctions are less necessary where a person is already being punished for their foolish behavior.

Think about two societies.  One is a community of average American families in Ohio, and the other is a few hundred hunters and trappers who live alone and isolated from each other in Alaska. The community in Ohio might condemn drug use, fearing that it could cause people to become irresponsible, unable to support their families.  In the wilds of Alaska, it’s unlikely that “society” would much care if an isolated hunter was using drugs.  If it interfered with his ability to hunt and trap, he would pay the price without any government sanction.

From this perspective, society’s system of morality, our code for choosing when to blame people and when not to blame people, might be viewed as a sort of tool, like a shovel or a scalpel.  Blame is a tool we use to discourage people from imposing external costs on society.

If I’m right, then stupidity that does not involve external costs would only be condemned when we actually care about the person hurting themselves.  And I think this is mostly true.  I might yell at a neighbor’s kid for scratching my car, but I won’t yell at that kid for not studying harder at school.  The child’s parents love their child much more than I do, and might yell at them for not doing their homework, for being “stupid”.  (That’s not to say parents cannot also punish children for selfish reasons, but surely the world contains at least some “tough love”.)

I am not saying that people consciously act as utilitarian moralizers, rather that we’ve evolved in such a way that we instinctively try to use our moral system in an effective way, a way that makes society work better.  We instinctively overestimate the difference between being stupid and being bad.

I’m also not saying that our moral sanctions are always appropriate—that would be absurd.  It’s highly unlikely that the prohibition of alcohol was optimal during 1920-33, but not optimal in either 1910 or 1940.  More likely, we sometimes make mistakes when deciding whom to blame and what sanctions to apply.

It’s also possible that our moral indignation is more convincing if we do not understand where it comes from and what’s its purpose is.  This sense of indignation is so innate that it might lead us to get angry at a zoo animal that kills a child that has wandered into its cage.  That anger won’t deter other zoo animals, but the basic instinct that makes us angry is appropriate in the vast majority of cases where children are intentionally harmed.

Indeed there have been times when I’ve yelled at my computer.

PS.  In politics, we are reassured if we find evidence that voters on the “other side” are merely being stupid, rather than malicious.