"A stupid person is a person who causes losses to another person or to a group of persons while himself deriving no gain and even possibly incurring losses."
I think all of your examples give the person some gain, or causes good to others.
Number 3 is called helpless for a reason. Even saints typically attempt to maximize gain, helpless do not - they tend to minimize loss instead.
In fact I would say many if not most people are helpless. This is part H1. Part H2 is the benefactor.
Likewise part I1 which is upper left triangle of I would be the inventor, scientist or good reformer. (They benefit but society benefits more). Bottom right of I would be good businessman. (Their own benefit is higher than society.) Top right B2 would be exploitative businessman. (Society loses a bit but the businessman gains a lot.)
As per political systems, capitalism attempts to promote rightmost two quadrants.
Socialism (not Stalinism) attempts to penalize bottom half.
Essentially the full graph would be a square with a 45º rotated square inside.
The stupid have two categories too - unnecessary cutting corners and messing up for minimal immediate gain with net loss (shortsighted) - top right of stupid quadrant - and plain old danger to society.
The textual definition is slightly off: there are stupid people who cause no loss to anyone but themselves†. Think of stupid people doing stupid things you can see on gifs and youtube where their attempt at doing something ranges from extremely unlikely to completely impossible to achieve in a very obvious way combined with a strong likeliness that Things Go Wrong in a very immediate and physical way. So the value on the Y axis (loss to other) can be zero.
I posit a better definition of stupidity that includes a lack of foresight of "obvious"†† damaging consequences would be more appropriate. A corollary would be Einstein's possibly apocryphal definition of insanity.
† OK unless the guy lives in the most remote area, there will probably be emergency services involved.
†† What's obvious to one may not be obvious to another, and it's a common mistake to conflate lack of knowledge with lack of foresight. We should strive to be kind in our expectations, yet the fact remains that some people are profoundly stupid to the point of being survivally challenged.
Based on that description, stupid people are very, very rare.
This is a classic case of "There are almost no irrational people." Or phrased in a way my mentors would put it: If you call someone irrational, you are being lazy and not trying to understand them.
I find it very difficult to buy the idea that a person is characteristically stupid. People does things like described by the definition all the time. It's called mistakes. Some people are ignorant sure. But my guess is that even the most ignorant person is not an idiot most of the time.
> When confronted for the first time with the Third Basic Law, rational people instinctively react with feelings of skepticism and incredulity.
> Most people do not act consistently. [...] We can calculate for each person his weighted average position in the plane of figure 1 quite independently from his degree of inconsistency.
> The only important exception to the rule is represented by the stupid people who normally show a strong proclivity toward perfect consistency in all fields of human endeavours
