I also thought this post might be named "Whack-a-Mole."
For a few solid years I picked on liberal arguments - no, the lack of arguments, the mere asserting of the same tired points, not really thought through, more emotional and social than rational, brought up in rotation and seemingly impervious to actual discussion. In that time, I have pointed the same finger at Christian fundamentalists, education theorists, and a few others here and there. Natural food/treatment/medicine folks have come up as well. They have come up recently in my personal life, so I will just mention them briefly here, as an example of a larger attitude about navigating life.
Before I kick them too hard, let me mention a preliminary conclusion that it is not only they, or liberals, or fundies, but all humankind that does this. Even I, though I at least try and fight against it and root it out. We all have these clusters of thought that reinforce each other and provide a way of escape when any one premise is threatened.
The naturals, the crunchies, are worried about pesticides because...well, they're chemicals...they might be dangerous...and we don't need so many...and corporations make money selling them to us..and they don't care about you...and there are rumors of hormonal somethings.
There is a second cluster of: people who don't watch their diets are fat and unhealthy...and the people who care a lot look pretty healthy...and a lot of them say organics are much, much better...and lots of newsletters...and they have these theories why...
Well, yeah. But the question is not whether young educated people who are very intentional in their eating and exercise look better than the people you see at Market Basket. The question about organic/natural eating is whether Group A would look different/live longer if they ate nonorganic, or Group B would look different/live longer if they ate organic. Once you ask that question, you see that Group A should absolutely look much, much better, but so what? Plus, in your readings and newsletters, who is going to publish the stories where someone tried those foods and it didn't work? Those stories slip beneath the waves.
There's no evidence. It's confirmation bias. Fine, pay extra money.
In medicine, they slip beneath the waves and they die, but because they died of an actual disease and not a useless treatment - no one tells you. NO ONE TELLS YOU THOSE STORIES.
So James's joke about the mathematician seems silly at first but is actually quite wise. "I assumed they were all identical and spherical." Because that forces you to drop the purely local, culture-based, treasured theories. Occam's Razor. Fewer moving parts. Empiricism. Theory kills.
We vaccinate the kids in one city of 1,000,000 and don't vaccinate the kids in another city of 1,000,000. (Or give them Vitamin A, cabbage juice*, bicycle helmets, or whatever) Then we count the dead kids. After we have done that, people's feelings about pesticides, or whether we CARE about our children (like the other parents don't), or food corporations, or God's preference for natural things, or how we did things in the Good Old Days - are entirely irrelevant. Count the dead children. That is all. Do what you want with your own life, but if your ideas will kill other people's children, don't you have some obligation to at least pause and think?
A cluster is more stable than a single point, certainly. We can feel protected by our cluster of ideas, even if each individual theory is weak. It's like Whack-a-Mole. Confirmation bias rules our thinking.
*Rodale Press breathlessly revealed that cabbage juice was a specific for treating ulcers in the 1970's. Not any worse than the stress model of psychologists, which MD's bought into for some reason. But both still dead wrong.