they're not stupid, just not interested in knowing.
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kinda what Dr Carson has been known for...willful ignorance

People are often quite specialized in the skills that they can learn or choose to learn, but that's a bit different from the sheer idiocy of Carson.

Someone (Mark Twain?) once said that the problem isn't so much what people don't know, but what they do know that ain't so. Carson knows an awful lot of things that ain't so!

But if you honestly think a dumb person could become a doctor (much less a surgeon,) you are far dumber than you imagine Carson to be. Doctors aren't subject matter experts on everything outside of medicine (as Carson has shown), but to mistake their ignorance for stupidity is pretty stupid as well.

I'm sure everyone who buys this line of thinking could totally be a doctor. You know, if they wanted to...

deductive reasoning appears to be completely missing.

My wife is a doctor. She understands scientific concepts, complex math, and a ton of other things I struggle with daily. She also thinks you can clean chef boyardee off a beige carpet with bleach. I feel like a lost little child when she explains things to me about the science behind things she handles day in and out, yet it all comes so naturally to her. None of it is rote memorization. In other matters, she's as helpless as I am with science. If someone suggested she got where she is by simply memorizing 8+ years of advanced science and math, mechanically muddling by through techmical memorization, I'd probably die laughing in their face.

We seem to have this compulsion to paint everyone we disagree with as dumb. And why not, right? I mean, I'm smart, so wouldn't anyone who thinks differently than me or not understand everything I do have to be dumb? It's a ridiculous and dangerous line of thinking. How much longer are we going to underestimate people due to some vanity-based belief in their stupidity, then be surprised when they win in the end? For a bunch of supposed dumbies, the republican party has plenty of politicians who aren't exactly handing us offices through their supposed stupidity.

If he'd ever operated on me, I'd be demanding an X-ray right now to make sure he didn't leave a pair of scissors in my head.

seriously, he comes off as VERY STUPID