I already mentioned this as a comment to another post, but it's worth repeating here: The human brain has evolved some "dedicated hardware" for accelerating certain tasks.

I already mentioned in that other post that one such hardware was for recognizing faces, and that false-positives generated by this hardware caused us have a feeling of hauntedness and ghosts (because the brain receives a subconscious signal indicating the presence of a face, but consciously looking around we see no one around).

Another such hardware (which I only briefly alluded to in the other post) was "agency detection". I.e. trying to figure out whether a certain event occurred "naturally", or because another agent (a friend, a foe, or a neutral?) caused it to happen. False positives from this hardware would cause us to "detect agency" where none was, and if the event seems something way out of the capacity for a human to control, and since humans seem to be the most powerful "natural" beings in the universe, the agent in question must be something supernatural, like God.

I don't have all the details worked out, but it seems plausible that agency-detection could have been naturally selected for, perhaps to be able to integrate better into a society, and to help with knowing when it is appropriate to cooperate and when it is appropriate to defect. It's a useful skill to be able to differentiate between "something good happened to me, because this person wanted something good to happen to me and made it happen. They cooperated (successfully). I should become their friend." versus "something good happened to me, despite this person wanting something bad to happen to me, but it backfired on them. They defected (unsuccessfully). I should be wary of them."

From there, bring in Anna Salamon and Steve Rayhawkideas about tag-along selection, and it seems like religion really may be a tag-along evolutionary attribute.

Anyway, I used to be scared of ghosts and the dark and stuff like that, but once I found out about the face-recognition hardware and its false positives (and other hardware, such as sound-location) this fear has almost completely disappeared almost instantaneously.

I was already atheist or agnostic (depending on what definitions you assign to those words) when I found out about the hardware false-positives, so I can't say for sure whether had I been religious, this would have converted me.

But if it worked at making me stop "believing"[1] in ghosts, then perhaps it could work at making people stop beliving in God as well.

1: Here I am using the term "believe" in the sense of Yvain's post on haunted rationalists. Like everyone else, I would assert that ghosts didn't really exist, and would be willing to make a wager that they didn't exist. And yet, like everyone else, I was still scared of them.

Here's another way of evaluating the sanity of religious belief:

It's arguable that the original believers of religion were insane (e.g. shamans with schizotypical personality disorder, temporal lobe epilepsy, etc...), yet with each subsequent believer in your culture, you are less and less insane to believe in it. During past history, it would only take a few insane or gullible people with good oratorical skills getting together to make religion sanely believable.

If you are religious because you see spirits, you are insane. If you are religious because your friend Shaman Bob sees spirits and predicts the rainfall, you aren't very smart, but you aren't insane either. If you are religious because your whole tribe believes in the spirits seen by Shaman Bob and has indoctrinated you from birth, you are not insane at all, you are a typical human.

If you want people to repeat this back, write it in a test, maybe even apply it in an academic context, a four-credit undergrad course will work.

If you want them to have it as the ground state of their mind in everyday life, you probably need to have taught them songs about it in kindergarten.

There was a time in history when religion was completely eliminated from the social and scientific life -- the Soviet period, roughly from 1920s to 1980s.

I'm not informed well enough to judge the effects the removal of religion had on the Soviet science. Granted, the country went from rubble to Sputnik and nuclear weapons, but it is hard for me to untangle the causes of this -- there were other powerful factors at work (e.g. "if you don't do good science, we'll send you and your family to GULAG").

One thing, however, is certain -- after the Soviet Union collapsed, religion conquered its lost positions back in a matter of a few years. The memetic sterilization that has been going on for several generations didn't help at all.

Now, about 20 years after the collapse, we see quite a lot of academics publicly mentioning God in their TV interviews, and you'll never hear a public politician mentioning that he is an atheist -- after doing so, his career would be instantly ruined.

To sum up, I have to agree with the posters suggesting that the 'God-shaped hole' wanting to be filled is innate. Figuring out whether religion is an epistemic need, a signaling tool, or both of these mixed in some proportion is another story.

I just read a nice blog post at neurowhoa.blogspot.com/2009/03/believer-brains-different-from-non.html, covering research on brain differences of believers vs. non-believers. The take away from the recent study was "religious conviction is associated with reduced neural responsivity to uncertainty and error". I'm hesitant to read too much into this particular study, but if there is something to this then the best way to spread rational thought would be to try to correct for this deficiency. Practicing not to let uncertainty or errors slide by, no matter how small, would result in a positive habit and develop their rationality skills.

It seems to me that the principal issue is that, even if you know all those things... that doesn't guarantee that you're actually applying them to your own beliefs or thought processes. There is no "view source" button for the brain, nor even a way to get a stack trace of how you arrived at a particular conclusion... and even if there were, most of us, most of the time, would not push the button or look at the trace, if we were happy with our existing/expected results.

In addition, most people are astonishingly bad at reasoning from the general to the specific... which means that if you don't mention religion explicitly in your hypothetical course, very few people will actually apply the skills in a religious context... especially if that part of their life is working out just fine, from their point of view.

It may be fictional evidence, but I think S.P. Somtow's idea that "The breaking of joy is the beginning of wisdom" has some applicability here... as even highly-motivated individuals have trouble learning to see their beliefs, as beliefs -- and therefore subject to the skills of rationality.

That is, if you think something is part of the territory, you're not going to apply something you think of as map-reading skills.

Hm, in fact, here's an interesting example. One of my students in the Mind Hackers' Guild just posted to our forum, complaining that by eliminating all his negative motivation regarding work, he now had no positive motivation either. But it was not apparent to him that the very fact he considered this a problem, was also an example of negative motivation.

That's because even though I teach people that ALL negative motivation is counterproductive for achieving long-term, directional goals (as opposed to very short-term or avoidance goals), people still assume that "negative motivation" means "motivations I don't like, or already know are irrational"... and so they make exceptions for all the things they think are "just the way it is". (Like in this man's case, an irrational fear linked to his need to "pay the bills".)

And this happens routinely with people, no matter how explicitly and repeatedly I state that, "no, you have to include those too". It seems like people still have to go through the process at least once or twice with someone pointing one of these out, before they "get it" that those other motivations also "count".

Heck, truth be told, I still sometimes take a while to find what hidden assumption in my thinking is leading to interference... even at times when I'd happily push the "view source" button or look at the stack trace... if only that were possible.

But since I routinely and trivially notice these map-territory confusions when my students do them, even without a view-source button -- heck, I can spot them from just a few words in the middle of their forum posts! -- I have to conclude that there is something innate at issue, besides me just not being a good enough teacher. After all, if I can spot these things in them, but not me, there must be some sort of bias at work.

To return to the question asked in the original post:

what could you teach people that is not directly about religion, which is true and useful as a general method of rationality, which would cause them to lose their religions?

My first reaction to the question -- too many constraints. I can't quickly think of anything that satisfies all three of them. However, if I'm allowed to drop one constraint, I'd drop the second one ("useful as a general method of rationality"), and my answer would be evolution.

In my experience, understanding evolution down to chemistry, down to predictable interactions of very simple parts that have nothing mystical or anthropomorphic about them can have a tremendous impact on one's further thinking.

My father grew up in a heavily religious family, and rejected religion at an early age. I'd say he was a clever fellow, but the turning point wasn't intelligence, it was what a horrible little bastard he was as a child, as any of his siblings would tell you.

If you just don't give a shit, all the emotional manipulation in the world will just wash over you like water off a duck's back. And that's all religion really has going for it, appealing to hope, to fear, to love, to respect, to piety, to community.

If you can teach people truly not to care, a huge rotten portion of their psyche falls away. There is a cost, of course... but this will do the job the post demands.

Recently I contemplated writing an "Atheist's Bible", to present the most important beliefs of atheists. Eventually I realized that this Atheist Bible would not mention atheism. "Atheism" is just the default belief state we were born with. Atheism isn't having reasons not to believe religion; it's not having reasons to believe religion. If one knows how the world works, there are no gaps for religion to fill.

The French Encyclopedia of the late 18th century was by design an atheist work; it carried out this design by not mentioning religion.

There are a couple of large gorillas in this room.

First, the examples of great scientists who were also religious shows that you don't have to be an atheist to make great discoveries. I think the example of Isaac Newton is especially instructive: not only did Newton's faith not interfere with his ability to understand reality, it also constituted the core of his motivation to do so (he believed that by understanding Nature he would come to a greater understanding of God). Faraday's example is also significant: his faith motivated him to refuse to work on chemical weapons for the British government.

Second, evidence shows that religious people are happier. Now, this happiness research is of course murky, and we should hesitate to make any grand conclusions on the basis of it. But if it is true, it is deeply problematic for the kind of rationality you are advocating. If rationalists should "just win", and we equate winning with happiness, and the faithful are happier than atheists, then we should all stop reading this blog and start going to church on Sundays.

There are subtleties here that await discovery. Note for example Taleb's hypothesis that the ancients specifically promoted religion as a way of preventing people from going to doctors, who killed more people than they saved until the 19th century. Robin made a similar point about the cost effectiveness of faith healing.