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Evolutionary psychology as "the truth-killer"

10 Benedict 23 July 2012 08:44PM

So, a little background- I've just come out as an atheist to my dad, a Christian pastor, who's convinced he can "fix" my thinking and is bombarding me with a number of flimsy arguments that I'm having trouble articulating a response to, and need help shutting down. The particular issue at the moment deals with non-theistic explanations for human psychology and things like love, morality, and beauty. After attempting to communicate explanations from evolutionary psychology, I was met with amused dismissal of the subject as "speculation". 

There's one book in particular he's having me read- The Reason for God by Timothy Keller. In the book, he brings up evolutionary psychology as an alternative to theistic explanations, and immediately dismisses it as apparently self-defeating.

"Evolutionists say that if God makes sense to us, it is not because he is really there, it's only because that belief helped us survive and so we are hardwired for it. However, if we can't trust our belief-forming faculties to tell us the truth about God, why should we trust them to tell us the truth about anything, including evolutionary science? If our cognitive faculties only tell us what we need to survive, not what is true, why trust them about anything at all?" -Timothy Keller

The obvious answer is that knowing the truth about things is generally advantageous to survival- but it hardly addresses the underlying assertion- that without [incredibly specific collection of god-beliefs and assorted dogmas], human brains can't arrive at truth because they weren't designed for it. And of course, I'm talking to a guy with an especially exacting definition of "truth" (100% certainty about the territory)- I could use an LW post that succinctly discusses the role and definition of truth, there. 

Another thing Dad likes to do is back me into a corner WRT morality and moral relativism- "Oh, but can you really believe that the act of rape doesn't have an inherent [wrongness]? Are you saying it was justified for [insert historical monster] to do [atrocity] because it would make him reproductively successful?" Armed only with evolutionary explanations for their behavior, I couldn't really respond- possibly my fault, since I haven't read the Morality sequence on account of I got stuck in the Quantum Physics ultrasequence, and knowing that reality is composed of complex amplitudes flowing between explicit configurations or aaasasdjgasjdga whatever the frig even (I CAN'T) has proven to be staggeringly unhelpful in this situation.

In addition to particular arguments WRT the question posed, I could also use recommendations for good, well-argued and accessible books on the subject of evolutionary psychology, with a focus on practical experimental results and application- the guy can't be given a book and not read it, so I'm hoping to at least get him to not dismiss the science as "speculation" or a joke. It's likely he's aware that the field evolutionary psychology is really prone to hindsight bias and thus ignores it completely, so along with the book, a good article or study demonstrating the accuracy and predictive power of the evolutionary psychological model would be appreciated.


How confident is your atheism?

10 r_claypool 14 June 2012 08:18PM

A friend recently asked how strongly I believe that my deconversion from Christianity was not a mistake. Here's my response, and for those of you who are not Christians, I'm just wondering what numbers you would give:

"There is a part of me that wants to say the chance is far less than 1 percent. But when I consider what 1% must mean about my ability to follow complex arguments and base my judgement on the right premises, it seems absurd to say that.

Trying to honestly estimate the chance that I'm wrong about the Bible being generally reliable is a fascinating exercise... I know the number is low, but I'm not sure how low.  

Today I would give myself a 1 in 20 chance of being wrong. If I were to consider the arguments of 20 other groups similar to Christian theologians, I would probably misunderstand them at least 1 time in 20. After talking with 20 groups that have a very different worldview, I might think they are all are mistaken, but once in a while, maybe 5% of the time, it would actually be me.

Wow, 5%!?! If I convert that into "There is a 5% probability that the God of the Bible exists and will send me to hell", I feel scared. But I know how to cheer myself up: I just say, "No way, the chance I'll end up in hell MUST be less than 5%. After all, the God of the Bible is CLEARLY just a big, mean alpha-monkey and... [rehearse all the atheistic arguments here]".

This back-and-forth from certainty to uncertainty makes me feel like I'm doing something seriously wrong.

So what about you? What chance do you place on some variant of Christianity turning up to be true, and what chance do you think a god of some sort exists?"

Numbers please.


[Link] A superintelligent solution to the Fermi paradox

0 Will_Newsome 30 May 2012 08:08PM


Long story short, it's an attempt to justify the planetarium hypothesis as a solution to the Fermi paradox. The first half is a discussion of how it and things like it are relevant to the intended purview of the blog, and the second half is the meat of the post. You'll probably want to just eat the meat, which I think is relevant to the interests of many LessWrong folk.

The blog is Computational Theology. It's new. I'll be the primary poster, but others are sought. I'll likely introduce the blog and more completely describe it in its own discussion post when more posts are up, hopefully including a few from people besides me, and when the archive will give a more informative indication of what to expect from the blog. Despite theism's suspect reputation here at LessWrong I suspect many of the future posts will be of interest to this audience anyway, especially for those of you who take interest in discussion of the singularity. The blog will even occasionally touch on rationality proper. So you might want to store the fact of the blog's existence somewhere deep in the back of your head. A link to the blog's main page can be found on my LessWrong user page if you forget the url.

I'd appreciate it if comments about the substance of the post were made on the blog post itself, but if you want to discuss the content here on LessWrong then that's okay too. Any meta-level comments about presentation, typos, or the post's relevance to LessWrong, should probably be put as comments on this discussion post. Thanks all!

Global warming is a better test of irrationality that theism

4 Stuart_Armstrong 16 March 2012 05:10PM

Theism is often a default test of irrationality on Less Wrong, but I propose that global warming denial would make a much better candidate.

Theism is a symptom of excess compartmentalisation, of not realising that absence of evidence is evidence of absence, of belief in belief, of privileging the hypothesis, and similar failings. But these are not intrinsically huge problems. Indeed, someone with a mild case of theism can have the same anticipations as someone without, and update their evidence in the same way. If they have moved their belief beyond refutation, in theory it thus fails to constrain their anticipations at all; and often this is the case in practice.

Contrast that with someone who denies the existence of anthropogenic global warming (AGW). This has all the signs of hypothesis privileging, but also reeks of fake justification, motivated skepticism, massive overconfidence (if they are truly ignorant of the facts of the debate), and simply the raising of politics above rationality. If I knew someone was a global warming skeptic, then I would expect them to be wrong in their beliefs and their anticipations, and to refuse to update when evidence worked against them. I would expect their judgement to be much more impaired than a theist's.

Of course, reverse stupidity isn't intelligence: simply because one accepts AGW, doesn't make one more rational. I work in England, in a university environment, so my acceptance of AGW is the default position and not a sign of rationality. But if someone is in a milieu that discouraged belief in AGW (one stereotype being heavily Republican areas of the US) and has risen above this, then kudos to them: their acceptance of AGW is indeed a sign of rationality.

Russ Roberts and Gary Taubes on confirmation bias [podcast]

4 fortyeridania 04 December 2011 05:51AM

Here is the link. The context is nutritional science and epidemiology, but confirmation bias is the primary theme pumping throughout the discussion. Gary Taubes has gained a reputation for contrarianism.* According to Taubes, the current nutritional paradigm (fat is bad, exercise is good, carbs are OK) does not deserve high credibility.

Roberts brings up the role of identity in perpetuating confirmation bias--a hypothesis has become part of you, so it has become that much harder to countenance contrary evidence. In this context they also talk about theism (Roberts is Jewish, while Taubes is an atheist). And, the program being EconTalk, Roberts draws analogies with economics.

*Sometime between 45 and 50 minutes in, Roberts points out that given this reputation, Taubes is susceptible to belief distortion as well:

What's your evidence that you are not just falling prey to the Ancel Keys and other folks who have made the same mistake?

I do not think Taubes gives a direct answer.

Religion, happiness, and Bayes

3 fortyeridania 04 October 2011 10:21AM

Religion apparently makes people happier. Is that evidence for the truth of religion, or against it?

(Of course, it matters which religion we're talking about, but let's just stick with theism generally.)

My initial inclination was to interpret this as evidence against theism, in the sense that it weakens the evidence for theism. Here's why:

  1. As all Bayesians know, a piece of information F is evidence for an hypothesis H to the degree that F depends on H. If F can happen just as easily without H as with it, then F is not evidence for H. The more likely we are to find F in a world without H, the weaker F is as evidence for H.
  2. Here, F is "Theism makes people happier." H is "Theism is true."
  3. The fact of widespread theism is evidence for H. The strength of this evidence depends on how likely such belief would be if H were false.
  4. As people are more likely to do something if it makes them happy, people are more likely to be theists given F.
  5. Thus F opens up a way for people to be theists even if H is false.
  6. It therefore weakens the evidence of widespread theism for the truth of H.
  7. Therefore, F should decrease one's confidence in H, i.e., it is evidence against H.

We could also put this in mathematical terms, where F represents an increase in the prior probability of our encountering the evidence. Since that prior is a denominator in Bayes' equation, a bigger one means a smaller posterior probability--in other words, weaker evidence.

OK, so that was my first thought.

But then I had second thoughts: Perhaps the evidence points the other way? If we reframe the finding as "Atheism causes unhappiness," or posit that contrarians (such as atheists) are dispositionally unhappy, does that change the sign of the evidence?

Obviously, I am confused. What's going on here?

Exclude the supernatural? My worldview is up for grabs.

23 r_claypool 25 June 2011 03:46AM


I was raised in the Churches of Christ and my family is all very serious about Christianity. About 3 years ago, I started to ask some hard questions, and the answers from other Christians were very unsatisfying. I used to believe that the Bible was, you know, inspired by a loving God, but its endorsement of genocide, the abuse of slaves, and the mistreatment of women and children really started to bother me.

I set out to study these issues as much as I could. I stayed up past midnight for weeks reading what Christians have to say, and this process triggered a real crisis of faith. What started out as a search for answers on Biblical genocide led me to places like commonsenseatheism.com. I learned that the Bible has serious credibility problems on lots of issues that no one ever told me about. Wow.

My Question

Now I'm pretty sure that the God of the Bible is man-made and Jesus of Nazareth was probably a failed prophet, but I don't have good reasons to reject the supernatural all together. I'm working through the sequences, but this process is slow. I will probably struggle with this question for months, maybe longer.

Excluding the Supernatural was interesting, but it left me wanting a more thorough explanation. Where do you think I should go from here? Should I just continue reading the sequences, and re-read them until the ideas gel? I'm coming from 30 years of Sunday School level thinking. It's not like I grew up with words like "epistemology" and "epiphenomenalism". If there is no supernatural, and I can be confident about that, I will need to re-evaluate a lot of things. My worldview is up for grabs.

A Bayesian Argument for Theistic Fine-Tuning

6 lukeprog 26 January 2011 05:38AM

Earlier, I linked to a Bayesian argument for the resurrection of Jesus - not because I think it succeeds, obviously, but because I thought Less Wrongers might be interested to know that at least since Swinburne, some Christian apologists have taken to defending their religious dogma with the language of Bayesian confirmation theory.

Another example of this is Robin Collins' version of the argument from fine-tuning for the existence of God. One of the major published objections to this kind of fine-tuning argument comes from the authors of that Bayesian argument for the Resurrection, Tim and Lydia McGrew. Another objection comes from Ikeda & Jefferys. Palonen also offers some observations.

I offer this merely for your curiosity.