So you really can't think of anything that is less likely to be observed if "it's all bullshit" than if it's not? There isn't any kind of aesthetic feeling you could feed to the wacko that he couldn't help but burst out in appreciation for?
As for evidence against that hypothesis, I think that depends largely upon how seriously you take some of the relevant premises in your wacko's model.
Not when I'm asking for evidence with a low Bayes factor, rather than a guaranteed low posterior.
Maybe an example would be in order. Let's say Bob is the wacko, but about quantum physics. Bob believe that the claims of quantum physics are just a big status game, and so are the results of the particle accelerators and everything. I could point to evidence like the atom bomb. If they were just arguing over meaningless crap the whole time, and assigning truth purely based on who has the most status, how did they ever get the understanding necessary to build an atom bomb, Bob?
There are a lot of different kinds of things in the world, and many of them are valuable in unexpected ways.
Right, like Halo. Except that millions of people like Halo even in the absence of a well-funded indoctrination campaign, and the fact that expressing appreciation for Halo won't endear them to the kewl kids of art.
It's not very impressive if people start to enjoy something after they've
spent their lives studying it.
You have to adjust for stuff like that.
Today I looked at the above illusion and thought, "Why do I keep thinking A and B are different colors? Obviously, something is wrong with how I am thinking about colors." I am being stupid when my I look at this illusion and I interpret the data in such a way to determine distinct colors. My expectations of reality and the information being transmitted and received are not lining up. If they were, the illusion wouldn't be an illusion.
The number 2 is prime; the number 6 is not. What about the number 1? Prime is defined as a natural number with exactly two divisors. 1 is an illusionary prime if you use a poor definition such as, "Prime is a number that is only divisible by itself and 1." Building on these bad assumptions could result in all sorts of weird results much like dividing by 0 can make it look like 2 = 1. What a tricky illusion!
An optical illusion is only bizarre if you are making a bad assumption about how your visual system is supposed to be working. It is a flaw in the Map, not the Territory. I should stop thinking that the visual system is reporting RGB style colors. It isn't. And, now that I know this, I am suddenly curious about what it is reporting. I have dropped a bad belief and am looking for a replacement. In this case, my visual system is distinguishing between something else entirely. Now that I have the right answer, this optical illusion should become as uninteresting as questioning whether 1 is prime. It should stop being weird, bizarre, and incredible. It merely highlights an obvious reality.
Addendum: This post was edited to fix a few problems and errors. If you are at all interested in more details behind the illusion presented here, there are a handful of excellent comments below.