One important characteristic of many stupid people is that they do not know it.
Think of Trump. A profoundly ignorant man who has never worked a day in his life. But an ignorant RICH man. And that makes the difference.
Because he had a rich father, he had no worries. He never had to apply for a job, never had to actually do anything to get his position.
And his business history of multiple bankruptcies, multiple bailouts by his father, thousands of lawsuits for non-payment of bills, all show how his stupidity is reflected in his business history.
The only success Trump has enjoyed is on reality television, where he played an ignorant bully. Not asking too much of him there.
Well, he did have more success in that he has, so far, successfully conned that segment of the population that can always be fooled, as well as successfully appealing to the persistent segment of gross racists in the country.
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the stupidity and danger of an "inheritance society" where all that really matters is how much money you have--no matter where it came from. The problem gets worse as time goes by and more fortunes are amassed (whether earned or not) to be inherited by more narcissists like Drumpf who may also learn early on that money is leverage that will get them whatever they want without ever lifting a finger. It could potentially lead to civilizational collapse due to widespread incompetence at the top.
Oh, yes.
Failing to understand what it is to know something is not on this list but is huge.
We see it all the time in many repeatedly ripping at Democratic politicians. Over time it becomes obvious that some truly believe they are far more competent and literally can't conceive that a professional might know something they don't. Bizarre but real.
“I know more about ISIS than the generals do, believe me.”
Well done! 
