Religion, happiness, and Bayes

post by fortyeridania · 2011-10-04T10:21:25.771Z · LW · GW · Legacy · 27 comments

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?

27 comments

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comment by Emile · 2011-10-04T15:37:39.160Z · LW(p) · GW(p)

In the balance of evidence, reasoning about "many people believe X, and it makes them happier" (whatever way that points) is a rounding error compared to evidence from archeology or textual analysis. It's not really worth fretting too much about it.

comment by lessdazed · 2011-10-04T11:20:11.550Z · LW(p) · GW(p)

Religion apparently makes people happier.

From the article:

individuals who turn to religion over time become, ceteris paribus, more satisfied, while those those turning away from it suffer a loss in their quality of life.

It could be that theists make non-theists unhappy, rather than religion making theists happy. Did they rule that out?

Replies from: fortyeridania
comment by fortyeridania · 2011-10-04T11:49:41.151Z · LW(p) · GW(p)

Not that I can tell, but that's an interesting suggestion. How would that work? What would it predict for societies with many religious people but few non-religious people, and vice versa?

Replies from: loup-vaillant
comment by loup-vaillant · 2011-10-04T15:32:42.461Z · LW(p) · GW(p)

It could work like that (though there were no conversion here). This kind of mob mentality can and do manifest itself over other channels than religion of course, but I think atheism is a less likely channel than religion itself.

Religion generally comes with a moral system, backed up by a set of beliefs. Among them, the belief that it is proper and good to believe (and, well, you know). It also comes with community by default, which can have a strong effect (compare r/atheism and r/religion: the more united tribe (atheists) sound much less tolerant overall).

The reason why someone turned to atheism may also influence his likelihood of persecuting believers. A Lukeprog scenario isn't likely to result in intolerance, for instance. Raw rebellion, followed by a "this is all bullshit anyway" rationalization may. I'd put being raised by atheists parents between the two, though it depends on the parents.

Anyway, I think the strongest factor is mob mentality. A group of anything that doesn't identify itself as such isn't very likely to make others miserable because of that "anything". And more often than not, atheists form such a group.

comment by lavalamp · 2011-10-04T12:53:42.791Z · LW(p) · GW(p)

Why do you expect happiness-causing beliefs to have a relationship to truthful beliefs?

Also, the happiness-production effects of religion might just be the benefits of being in the social majority. For example, see: http://epiphenom.fieldofscience.com/2011/05/being-religious-doesnt-make-english.html

Replies from: PhilGoetz, antigonus
comment by PhilGoetz · 2011-10-05T02:27:54.078Z · LW(p) · GW(p)

Why do you expect happiness-causing beliefs to have a relationship to truthful beliefs?

The post already is the answer to this question. The relationship posited is explaining-away, in the Bayesian sense.

comment by antigonus · 2011-10-04T16:11:18.818Z · LW(p) · GW(p)

Why do you expect happiness-causing beliefs to have a relationship to truthful beliefs?

The point is that if religion does make people happier, this makes it more probable than before on naturalism that lots of people would be theists, hence weakens the evidence for theism that comes from the surprising-ness of lots of people being theists. In other words, theism's making people happier helps screen off the truth of theism from the phenomenon of widespread religious belief.

Of course, to be evidence against theism, the happiness thing has to lower the probability of theism on all of the evidence, not just lower it on one portion of the evidence. Some theists may want to argue that theists being happier is itself more likely on theism than on non-theism, and this isn't terribly implausible. Without having a healthier sense of the conditional probabilities involved than I actually do, I don't know how to evaluate the overall effect on theism's posterior probability.

Replies from: antigonus
comment by antigonus · 2011-10-04T16:44:55.990Z · LW(p) · GW(p)

Actually, I should be more clear. Let T = theism, H = theism makes people happier, L = lots of people are theists. Then H&L are evidence for T iff the quotient P(H&L|T)/P(H&L|~T) > 1. We can rewrite this quotient as P(L|H&T)/P(L|H&~T) * P(H|T)/P(~H|T). Then the thread-starter's argument at best shows that T is irrelevant to L once we know H, hence P(L|H&T)/P(L|H&~T) = 1. So in this best-case scenario, the quotient becomes P(H|T)/P(H|~T). If theists can show this is greater than 1, then H&L still ends up as evidence for theism. So that's what you really have to be asking.

comment by printing-spoon · 2011-10-04T12:23:02.794Z · LW(p) · GW(p)

On the other hand, religion predicts more confidently than atheism that having religion makes people happier.

comment by Hyena · 2011-10-04T12:40:33.258Z · LW(p) · GW(p)

You would want to approach it conditioned from the likelihood that an arbitrary happy belief is one which is also false. I am not sure this calculation could be made with much confidence, whether statistical or instinctual.

comment by [deleted] · 2011-10-04T10:45:55.687Z · LW(p) · GW(p)

You said The fact of widespread theism is evidence for [theism is true]. This sounds mistaken to me. How do you derive it?

Replies from: wedrifid, fortyeridania
comment by wedrifid · 2011-10-04T13:09:24.144Z · LW(p) · GW(p)

You said The fact of widespread theism is evidence for [theism is true]. This sounds mistaken to me. How do you derive it?

That seems accurate to me. Humans seem to have a bias towards induction and induction seems to work. Lots of humans thinking something seems to happen more for true things than for untrue things.

It isn't especially strong evidence. It is also evidence that you have probably already taken into account by the time you choose to ask "is theism true?" and should avoid double counting.

comment by fortyeridania · 2011-10-04T11:18:12.644Z · LW(p) · GW(p)

Hmm...I guess I just assumed that people were more likely to believe something true than something false, other things being equal. What do you think about that?

Also, I should note this: Even if people aren't more likely to believe something true than false, the original finding (that theism causes happiness) should still militate against theism, because however wrong people may go in their beliefs, surely they are even less likely to believe something true if believing a false thing can make them happy. Right?

Replies from: None
comment by [deleted] · 2011-10-04T12:16:59.359Z · LW(p) · GW(p)

people were more likely to believe something true than something false

In general I reject this. Maybe it holds for small classes of statements that regard direct experience (for example "stuff falls down", "getting hit by a car is bad for you") but certainly not for abstract things like theism.

To believe in something because others do allows false beliefs to circularly maintain themselves. On the other hand, if you believed in something because others believe in it for the right reasons then learning that many people believe in something for the wrong reason (e.g. because it makes them happy) will decrease your estimate.

Replies from: fortyeridania, wedrifid, AlexMennen
comment by fortyeridania · 2011-10-05T01:50:48.997Z · LW(p) · GW(p)

In general I reject this.

As crazy and improbable as an idea might seem, surely it would seem even less credible if you learned that literally nobody believed it. Turning this around, wouldn't it seem at least a little more probable if a bunch of people believed it? And shouldn't this hold for abstract beliefs, too?

comment by wedrifid · 2011-10-04T13:17:42.164Z · LW(p) · GW(p)

In general I reject this. Maybe it holds for small classes of statements that regard direct experience (for example "stuff falls down", "getting hit by a car is bad for you") but certainly not for abstract things like theism.

Bear in mind that "more likely" is an extremely weak claim. To say that it certainly doesn't hold for abstract things is, therefore, a rather strong claim. Perhaps stronger than you intend. It would be extremely surprising if humans weren't on average slightly better than random at arriving at correct abstract beliefs even of that type.

comment by AlexMennen · 2011-10-04T15:11:03.566Z · LW(p) · GW(p)

Most people believe that it is impossible to travel faster than light, although they don't understand why that is and it is all very abstract to them. I speculate that this might be connected with the fact that it is impossible to travel faster than light.

Replies from: None
comment by [deleted] · 2011-10-04T15:18:44.399Z · LW(p) · GW(p)

This is too opaque for me to understand. What is the moral of that comment?

Replies from: AlexMennen
comment by AlexMennen · 2011-10-04T15:24:54.882Z · LW(p) · GW(p)

I was suggesting that people's beliefs are correlated with reality even in abstract areas.

Replies from: None
comment by [deleted] · 2011-10-04T15:26:31.840Z · LW(p) · GW(p)

Oh that simple.. well yes sometimes the majority is right and sometimes it is wrong.

Replies from: RolfAndreassen, JoshuaZ
comment by RolfAndreassen · 2011-10-04T19:37:22.732Z · LW(p) · GW(p)

You propose a theory of maximum entropy, apparently retreating from your original statement that "`people are more likely to believe true things' holds only for a limited class of theories." Can you suggest a test for what sort of beliefs are likely to be [un]correlated with truth?

comment by JoshuaZ · 2011-10-05T03:39:21.237Z · LW(p) · GW(p)

Your comment doesn't seem to respond to Alex in a useful way. Alex's point is not just that the majority is sometimes right and sometimes wrong but that there's a tendency for it to be more right than wrong even for abstract issues. In this context, simply saying what you have said seems to be a restatement of your earlier argument rather than anything new.

Incidentally, there are other examples of how in large areas of abstract thought the majority will generally be right. The speed of light example is a pretty weak one. Here are some more broad examples.

First, if you ask people to do arithmetic with small numbers they are far more likely to get it correct than to make a mistake. Even in questions where they are likely to make a mistake (involving larger numbers) the plurality answers are generally correct.

Second, there's a lot of evidence that across a wide variety of fields, of varying degrees of abstraction, crowds do quite well. In one famous but unscientific example, 91% of the time in the show "Who Wants to be a Millionaire" the audience when asked got the right answer often by a high percentage. They also did better than "smart" people. The way this works is the contestants who are trying to answer multiple choice questions have a set of different "lifelines" which they can each use once. One of those lifelines is to poll the audience for which of the four answers they think is correct. The audience was generally correct a large fraction of the time.

Third, for more abstracted issues one can look at things like the GSS data. For the GSS data although large fractions of the public get some science questions wrong, for every factual science issue, the majority, and generally a clear majority. This is not limited to the GSS but has been true for other studies that more specifically are trying to study scientific knowledge levels. Other studies have shown similar numbers.

One should also consider that by most metrics there are a lot more false hypotheses than true ones. If you pick a random hypothesis people are most likely going to be able to recognize it as imply wrong. (e.g. If I said "True or false the tides are caused by the sun and moon influencing the Earth with __" and I had in that blank any of {elephants, lasers, the Illuminati, Grover Cleveland, Gandalf} people would likely say false to any of them. If I had in that blank "electromagnetism" a slightly larger percentage would might say true, but it would almost certainly be tiny. And this is a short hypothesis. Almost any long hypothesis will simply have the absurdity heuristic applied to it. This means that at a very weak level, people will have to be right most of the time simply because they will discount absurd or overly convoluted hypotheses.

The question that seems to be more interesting is whether of the set of hypotheses that have come to attention either from evidence or from historical accident, whether people perform better than randomly. I don't know, and I'm not sure this is even well-defined. But claiming some form of this, that on the boundary of interesting non-trivial hypotheses, the majority does not better than random chance, might be an easier claim to make.

comment by Prismattic · 2011-10-09T02:38:44.087Z · LW(p) · GW(p)

For some reason, the bibliography of the linked VoxEU article omits this study which did not find the link between religion and happiness to be statistically significant in the Netherlands or Denmark.

I have not had a chance to check the average article quality, so I haven't yet decided whether I think that it's awesome that there is a Journal of Happiness Studies.

I tend to think the general thrust of the top post is a bit odd. Surely it matters why the religious are happier if that is the case. I attribute it to some mix of stronger social ties (this would more tend to explain the result in the study I linked, since social ties in the majority nonreligious Western Europe are less correlated with religious practice) and belief in the just world fallacy (either in the belief that people actually get what they deserve, or the belief in a compensating afterlife). The first explanation has no bearing on the truthfulness of religion; the second weakens its case (Ockham's razor -- the world is unjust is a much simpler explanation than any of the rationalizations presented to make the case for a just world).

comment by zntneo · 2011-10-09T02:13:50.181Z · LW(p) · GW(p)

I think the experimental evidence for religion making people happier is horribly flawed (i might be a bit biased given i worked in a lab who was doing work on the subject). Here are some reasons:

Generally the researchers in the field assume that you can just do a linear analysis of religiosity and happiness, meaning using a scale of not religious to very religious and then making not religious=atheist, which is clearly not a good assumption. In fact studies have shown in the past a curvilinear relationship where the "more certain" positions of atheist and theist are as happy as each other . Also, even making sure that the people in the atheist pool are atheists is hard. If i remember correctly the pew research that showed a certain number of atheists in the country also found 40% of those atheists believed in god.

Second reason is : generally the studies use church attendance as its operational definition of religion which does not control for the social support that being in a church provides and when studies control for that generally they find no difference.

Now if this post is about if its true that it makes people happier what does that mean then please ignore.

Edit: i hope thats better

Replies from: pedanterrific
comment by pedanterrific · 2011-10-09T02:26:51.335Z · LW(p) · GW(p)

religion making people __ is horribly flawed

Happy?

do a linear analysis of __ which is clearly not

Religiosity?

Now if this post is about if its true that it makes people happier what does that mean then please ignore.

You lost me. More punctuation, maybe?

Replies from: zntneo
comment by zntneo · 2011-10-09T02:33:09.748Z · LW(p) · GW(p)

Holy crap i'll edit hold on

comment by PhilGoetz · 2011-10-05T02:26:14.568Z · LW(p) · GW(p)

Observing a change in the degree of happiness that religion provided could cause you to change the probability you assign to its truth. But when you start with already having observed the current level of belief and the level of happiness provided, I don't think you can adjust your belief for happiness, because it's already factored into the current level of belief.

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

If religion makes people happier, why do you care whether it's true?