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Here are some pieces so interesting I'm at a loss for further commentary:Insurers are starting to account for the costs of global climate change.The two-dollar bill is making a big comeback.Barak Obama is the real deal. Click and listen why.Some...

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Why we believe what we believe

I found a comment on someone else's blog which I thought was pretty interesting. The post was about how a study of identical twins showed that some political and social attitudes had a high degree of hereditability. The commenter, who

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Seems like there are two questions here. The first is, is there any reason to believe that genetically-determined beliefs on a given topic are likely to be correct? In other words, if our genes largely determine our beliefs on abortion, is there a plausible mechanism whereby selection effects would tend to amplify genes which lead to "correct" beliefs in that area? It's hard to credit that this is the case, because abortion is such a specific question and probably not one which has been relevant for survival far back into history. So we would not have very good grounds to conclude that our beliefs in this area are correct. They are more likely to be what Gould called a "spandrel", an accidental byproduct of genes which were selected for other purposes.

The second question arises for genes where we can in fact come up with a plausible story along these lines. Consider for example attitudes towards fire. Fire has been around for a long time, it is dangerous and powerful, so it might be plausible that there is effective selection for genes which affect attitudes and behavior towards fire. Therefore a priori one might assume that his own attitudes towards fire are "correct" even if genetically determined. However, suppose one then discovers that his own attitudes towards fire are very different from those of society as a whole. Wouldn't it then be reasonable to conclude that it is more likely that society's attitudes are the correct ones, and that ones own attitudes are due to some genetic mistake or malfunction, since members of society have been subject to the same genetic selection pressures but are far more numerous than onesself?

Therefore it seems that whether or not one can come up with a mechanism for how a genetically based belief can be reasonably attributed to selection pressure and presumed to be correct, either way you can't justify ignoring the social consensus in favor of your genetically-determined belief.

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Michael, your first two questions are interesting; I hope they will be answered someday. A net zero correlation could result from several non-zero correlated influence pathways that cancel each other.

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What beliefs are correlated with the belief in the result of this study?

With the propensity to debias beliefs?

What reference classes should be used?

By the way, 0% genetic influence on attitudes towards intellect/books/chess/etc strikes me as Radically unlikely given genetic influences on IQ and on five factor "openness", the latter of which correlates at least .3 with IQ and basically *is* attitude towards intellect/books/chess/etc.

Lots of data suggests the religious belief is negatively g loaded.g loading may sometimes be difficult to define simply if relationships are non-linear, so g-type effects may be more pervasive than typically stated.

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Making fine distinctions in understanding hereditability of attitudes

Tyler Cowen points to Robin Hansen who points to this paper by Olson, Vernon, Harris, and Jang, "The heritability of attitudes: a study of twins". Robin writes, summarizing the paper, your differing attitudes on abortion, birth control, immigrants, gen...

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John, thanks for noticing; I corrected "twins" to "twin pairs."

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asked 339 twins for their attitudes on 30 topics.

Where does that number come from? It can't be right (it's odd) and the paper says 672 (336 pairs) on p. 848.

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"The subject here is your random deviation from that genetic average. And the suggestion is to estimate and repudiate that random component of your beliefs, rather than to repudiate all components of your belief."

Hmm. I was thinking that the idea was that we should recognize that many of our beliefs are held for reasons other than their truth-quality. For instance, they may be held for genetic reasons, social reasons, or ego reasons. This should cause us to re-examine our beliefs and be sure that we're testing them on truthfulness, rather than on intuition.

In other words, I don't know why I would necessarily accept as true a belief that was consistent with the genetic average. Even average genetics, cleaned for random variations from the norm, could cause wrong beliefs.

As Nietzsche put it, there are certain assumptions without which our lives would be unliveable. But this does not mean that those assumptions are true. The conditions of life, in his words, could contain error.

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Andrew, yes average genetic beliefs can be explained by selection, which might well tend to induce correct beliefs. The subject here is your random deviation from that genetic average. And the suggestion is to estimate and repudiate that random component of your beliefs, rather than to repudiate all components of your belief.

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I guess to my view:

a) This granular data seems to clash with aggregate data showing that certain populations without a shared genetic background tend to share certain sets of beliefs about the exact things identified here as "genetically caused" (i.e. urban populations tend to be far more pro-immigrant). Conflicting data is the most interesting kind.

b) If social factors can cause beliefs (pdf23ds's .33 correlation) even though there is a genetic component, then without further investigation it would not be reasonable to conclude that my beliefs about immigration are a product of my genetics. Further this possibility of 'outweighing' genetics with socialization could suggest that it is possible to come to reasonable beliefs about immigration even if your genes say otherwise - you can 'beat' your genes.

c) Additionally, a belief caused by my genes could nevertheless be correct. I am highly programmed to care about the well-being of my children, for instance, which is probably also a correct behavior.

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Paul, I didn't intend a tipping point rule, wherein you abandon all your differences if more than half of the cause is random. Rather you should use the genetic data to help estimate the random component and then abandon that.

Also, I was trying to distinguish a resource cost, such as time or money, from a value-induced cost of avoiding error. If you gain value from your bias, such as peer approval, I still want it to be called bias, but I also don't want to call it bias if you just didn't have the time to get or process the relevant info that would have reduced your error. But, yes, I'm not entirely sure that this line can be coherently drawn.

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Well, acting on your definition of bias as costlessly or near-costlessly avoidable error, I'm not so sure. Even if we limit ourselves to individual cost rather than social cost, it seems like there's a rather large individual cost to the decison rule you propose.

To highlight that, let me state it in the starkest form.

Hanson's Rule: If, based on aggregate evidence, it is more likely than not that the deviation from the mean of my belief on issue N is attributable to non-reasoned factors*, then I should modify my belief on N to the mean.

But some of the things we most value in life are beliefs based on non-reasoned factors. For example, someone whose belief on the dimension of organized religion deviates from the mean because that person happens to be a Jew would suffer a massive personal cost to conforming their view to the mean. (I think you've really got to get the mode here. It's hard to imagine what the mean of religion would be. The mode would be what -- Hinduism?)

*It's easy to apply this rule in a way that creates a fallacy of accident, too. Would you demand that Richard Dawkins abandon his decidedly non-mean views about organized religion because, statistically, they're more likely to be rooted in non-reasoned sources than the mean? Obviously not, because Dawkins's individual views about organized religion are tracable to things like the scientific method that we do believe are correlated with truth, even if on average outliers on that dimension are not so correlated. So far so good, *we* can distinguish Dawkins... but how is Dawkins to distinguish himself from the average non-rational-outlier on your test? He can't rely on his own belief that his views are based on rational priors, because everyone has that belief, it's an obvious bias. Why isn't it rational for Dawkins personally to change his beliefs?

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Paul, yes, it is possible, though hardly obvious, that bias produces social benefit. Hopefully we will discuss that issue in this forum in more detail. But avoidable error it is, make no doubt about that.

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Ah-ha, but I have another argument. (Yes, I've been thinking about this for the last two hours.) People who hold opinions that are widely varied from the mean, even without any present good reason to hold them, are providing a social benefit. They have an incentive to discover reasons and arguments in favor of their claim, increasing the general store of knowledge, and they also have an incentive to challenge the received (general) opinion, encouraging people who believe in that opinion to develop reasons and arguments in its defense. These benefits would go away if people followed your advice and consciously adopted mean opinions where they believed their original opinion had bad priors. Thus individually rational behavior would lead to a socially irrational result.

(John Stuart Mill, of course, gets credit for this whole line of argument.)

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Uh, never mind. That last comment was just wrong -- I rethought it. Sorry.

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