Retroviral genetic engineering once we know what genes control rationality.
It has the advantage that it would be in people’s self-interest to do this. I suspect that some kind of individually beneficial modification is the solution.
Psychosurgery or pharmaceutical intervention to encourage some of the more positive autistic spectrum cognitive traits seems more likely to work than this. We are far from identifying the genetic basis of intelligence or exceptional intelligence, never mind an aspect as specific as rationality.
It’s also not clear that it is in someone’s self interest to do this. I know you said retroviral genetic engineering, but for now I’ll assume that it would only be possible on embryos. In that case, if someone really wanted grand children, it is not clear that making these alterations in her children would be the best way to achieve that goal.
Retroviral genetic engineering once we know what genes control rationality.
Would those genes have time to be expressed later in life?
Also, how heritable is rationality? How do we even measure it, to find out? And if we find some subset of our genes which can be reasonably tweaked to enhance rationality, I’m guessing that they would probably affect people’s capability to be rational, in a bunch of indirect ways. There would have to be a memetic component, alongside any genetic tweaks we make. I think.
That sounds a bit too long-term, though. By the time that becomes viable and socially acceptable (if it ever becomes so), we will be many presidencies into the future.
Also, for people to recognize that rationality enhancement is in their best interest you need some baseline level of rationality.
I’m skeptical of a strong heritability for rationality independent of IQ. Your original statement suggested to me that you knew of stronger evidence than ‘most things are heritable’. If you don’t know of any such evidence I’m inclined to remain firmly on the fence.
Have you read The Millionaire Next Door? The book is about people of very ordinary intelligence who are more rational about money than many smarter people.
I haven’t read it but I don’t think this kind of example talks directly to the question of whether rationality is a strongly heritable trait independent of IQ. My current hypothesis (not strongly held or supported by large amounts of evidence) is that rationality is more a learned skill or habit of thinking which will tend to correlate with IQ (because higher IQ people will learn it easier/faster and apply it better) but that some high IQ people have failed to learn it and some lower IQ people have become quite good at it.
Examples of lower IQ people who are more rational than higher IQ people do not on their own help to distinguish whether rationality is a separately heritable trait from IQ or a learned habit of thinking.
I would not be hugely surprised if certain big 5 personality traits or other potentially heritable personality traits made people more inclined to learn rational thinking which might provide an indirect basis for heritability of rationality.
They invested conservatively, not aggressively. I expect they’re better off than people who got heavily into debt, but probably not as well off as some people who were insiders enough to not lose too much when they made bad investments for other people.
I meant aggressively in the sense of well-diversified and stock-heavy (hence the “long-term” bit). If they got rich off of bond interest, well, it wasn’t investment acumen that explains their success, but a) raw earning power, and b) not spending it all.
Unfortunately, exactly what they invested in wasn’t something I was very sensitive to, and I don’t remember it.
Generally, they had fairly ordinary incomes, and they invested in things which were considered low-risk at the time. A fair number of them had real estate in the sense of owning car dealerships (used car lots?), with the land under the business being a large part of their wealth.
They disliked spending money. It was common for them to be men whose wives made a full-time job of running the household cheaply. (There was a later book called The Millionaire Woman Next Door.)
For the time being, I’ll just consider literacy as a binary quality, leaving aside differences in ability. In developed countries, with literacy rates around 99%, literacy is probably some what heritable because that <1% cannot read because of some sort of learning defect with a heritable component.
In Mail, with a 26.2% literacy rate, literacy is not very heritable. The illiterate there are a consequence of lack of educational opportunities. I think that the situation we are in regarding the phenotype of “rational” is closer to the Mali scenario rather than the developed world scenario.
You mean in general or for rationality in particular? Lots of things are heritable, to varying (and often disputed) extents. I tend to think genetic factors are often underestimated when explaining human variability. I’m not familiar enough with the evidence for heritability of other high level cognitive abilities to make a very good estimate for the heritability of rationality however.
I’ve just bought What Intelligence Tests Miss for my Kindle after reading the article series here. As I said, I’m skeptical that rationality as an independent factor from IQ is strongly heritable but I’m open to evidence to the contrary which is why I was curious if you had any.
You should still have a prior. “I don’t have enough detailed info” is not an excuse for not having a prior.
No, it’s not, but I think it’s a reasonable excuse for not having a more specific prior than ‘low and uncertain’. Being more specific in my prior would not be very useful without being more specific about what exactly the question is. I sometimes see a tendency here to overconfidence in estimates simply because a bunch of rather arbitrary priors have been multiplied together and produced a comfortingly precise number.
Why not just take the probability distribution of heritability coefficients for traits-in-general as your prior?
I don’t know what it is. I suspect it is not a well established piece of information. I’m not convinced that heritability for ‘traits-in-general’ is a good basis for rationality in particular. Do you have a reference for a good estimate for this distribution?
I feel that people who refuse to give a numerical prior and use protestations of ignorance (that can be cured with a 5-second google search) as an excuse to say “very low” are really engaging in motivated cognition, usually without realizing.
Whenever one says “I don’t have much info so I think the probability of X is really low”, one should ask oneself:
(1) Would I apply the same argument to ~X ? A “very low” prior for X implies a very high prior for ~X. Am I exploiting the framing of using X rather than ~X to engage in motivated skepticism?
(2) Has it even crossed my mind to think about how easy it might be to find the info, and if not, am I willfully clinging to ignorance in order to avoid having to give up a cherished belief?
I never qualified ‘low’ with ‘very’ or ‘really’. If numbers make you feel better ‘low’ means roughly 1-10% probability. I find it a little backwards when someone focuses so much on precisely quantifying an estimate like this before the exact question is even clarified. I see it a lot from non-technical managers as a programmer.
I started this thread by asking for the information you were using to arrive at your (implied) high confidence in a genetic basis for rationality. There’s been several recent articles about What Intelligence Tests Miss and I haven’t started reading it yet (though it is now sitting on my Kindle) so I was already thinking about whether rationality as a separate trait from IQ is a distinct and measurable trait. I haven’t seen enough evidence yet to convince me that it is so your implication that it is and is strongly heritable made me wonder if you were privy to some information that I didn’t know.
While assigning numerical probabilities to priors and doing some math can be useful for certain problems I don’t think it is necessarily the best starting point when investigating complex issues like this with actual human brains rather than ideal Bayesian reasoning agents. I’m still in data gathering mode at the moment and don’t see a great benefit to throwing out exact priors as a badge of Bayesian honor.
This is what I meant about quantifying the probability estimate before clarifying the exact question. As I said originally, I’m skeptical of a strong heritability for rationality independent of IQ. I’m not sure what the correct statistical terminology is for talking about this kind of question. I think there is a low probability that a targeted genetic modification could increase rationality independent of IQ in a significant and measurable way. That belief doesn’t map in a straightforward way onto a claim about the heritability of rationality. I’m expecting What Intelligence Tests Miss to help clarify my thinking about what kind of test could even be used to reliably separate a ‘rationality’ cognitive trait from IQ which would be a necessary precondition to measuring the heritability of rationality.
Given that memory, verbal intelligence, spatial reasoning and general intelligence all have values of H of around 0.4, it seems that P{H>0.3) ~ 70%
These all correlate significantly with IQ however I believe (correct me if you think I’m wrong on this). It’s at least plausible that targeted genetic modifications could improve say spatial or verbal reasoning significantly more than IQ (perhaps by lowering scores in other areas) since there is some evidence of sex differences in these traits. Rationality seems more like a way of reasoning and a higher level trait than these ‘specialized’ forms of intelligence however.
Rationality seems more like a way of reasoning and a higher level trait than these ‘specialized’ forms of intelligence however.
Maybe. Actually, I think that the dominant theory around here is that rationality is actually the result of an atrophied motivated-cognition module, so perfect rationality is not a question of creating a new brain module, but subtracting off the distorting mechanisms that we are blighted with.
I realize that “brain module” != “distinct patch of cortex real estate”, but have there been any cases of brain damage that have increased a person’s rationality in some areas? I am aware that depression and certain autism spectrum traits have this property, but I’m curious if physical trauma has done anything similar.
I don’t know, but without a standardized test for rationality (like there is for IQ), how would we even notice?
Googling for “can brain injury cause autism” leads to conflicting info:
“This is a question which arises again and again, it’s other form is ‘Can brain injury cause autism?’ Of course the answer is most definitely, yes!”
“Blows to the head, lack of oxygen, and other physical trauma can certainly cause brain damage. Brain damaged children may have behaviors similar to those of autistic children. But physical injury cannot cause accurately diagnosed autism. Certainly a few non-traumatic falls in infancy are NOT the cause of autism in a toddler.”
To test this, you’d need to somehow identify a group of patients that were going to receive some kind of very specific brain surgery, and give them a pre- and post- rationality test.
At this point I was mostly wondering if there were any motivating anecdotes such as Phineas Gage or gourmand syndrome, except with a noticeable personality change towards rationality. Someone changing his political orientation, becoming less superstitious, or gambling less as a result of an injury could be useful (and, as a caveat, all could be caused by damage that has nothing to do with rationality).
and even then you would only expect 1 in 50 or so kinds of brain surgery to remove the part that caused (say) motivated cognition, and only one in 5 or so of those to not do so much damage that you could actually detect the positive effect.
Better, use high-precision real-time brain imaging to image somebody’s brain when motivated cognition is happening, then use high-precision TMS to switch just that part off.
You can apply laws of probability to intuitive notions of plausibility as well (and some informal arguments won’t be valid if they violate these laws, like both X and ~X being unexpected). Specific numbers don’t have to be thought up to do that.
Retroviral genetic engineering once we know what genes control rationality.
It has the advantage that it would be in people’s self-interest to do this. I suspect that some kind of individually beneficial modification is the solution.
Psychosurgery or pharmaceutical intervention to encourage some of the more positive autistic spectrum cognitive traits seems more likely to work than this. We are far from identifying the genetic basis of intelligence or exceptional intelligence, never mind an aspect as specific as rationality.
It’s also not clear that it is in someone’s self interest to do this. I know you said retroviral genetic engineering, but for now I’ll assume that it would only be possible on embryos. In that case, if someone really wanted grand children, it is not clear that making these alterations in her children would be the best way to achieve that goal.
Would those genes have time to be expressed later in life?
Also, how heritable is rationality? How do we even measure it, to find out? And if we find some subset of our genes which can be reasonably tweaked to enhance rationality, I’m guessing that they would probably affect people’s capability to be rational, in a bunch of indirect ways. There would have to be a memetic component, alongside any genetic tweaks we make. I think.
That sounds a bit too long-term, though. By the time that becomes viable and socially acceptable (if it ever becomes so), we will be many presidencies into the future.
Also, for people to recognize that rationality enhancement is in their best interest you need some baseline level of rationality.
Do you know of any evidence suggesting strong heritability of rationality?
Most things are heritable. IQ, for example, with a coefficient of 0.4.
I’m skeptical of a strong heritability for rationality independent of IQ. Your original statement suggested to me that you knew of stronger evidence than ‘most things are heritable’. If you don’t know of any such evidence I’m inclined to remain firmly on the fence.
Have you read The Millionaire Next Door? The book is about people of very ordinary intelligence who are more rational about money than many smarter people.
I haven’t read it but I don’t think this kind of example talks directly to the question of whether rationality is a strongly heritable trait independent of IQ. My current hypothesis (not strongly held or supported by large amounts of evidence) is that rationality is more a learned skill or habit of thinking which will tend to correlate with IQ (because higher IQ people will learn it easier/faster and apply it better) but that some high IQ people have failed to learn it and some lower IQ people have become quite good at it.
Examples of lower IQ people who are more rational than higher IQ people do not on their own help to distinguish whether rationality is a separately heritable trait from IQ or a learned habit of thinking.
I would not be hugely surprised if certain big 5 personality traits or other potentially heritable personality traits made people more inclined to learn rational thinking which might provide an indirect basis for heritability of rationality.
I wasn’t reading carefully, so I just offered evidence that rationality is somewhat independent of IQ.
Didn’t the people in that book get rich by saving a lot and investing aggressively for the long term?
How’s that strategy working out?
I don’t know of any follow-ups.
They invested conservatively, not aggressively. I expect they’re better off than people who got heavily into debt, but probably not as well off as some people who were insiders enough to not lose too much when they made bad investments for other people.
I meant aggressively in the sense of well-diversified and stock-heavy (hence the “long-term” bit). If they got rich off of bond interest, well, it wasn’t investment acumen that explains their success, but a) raw earning power, and b) not spending it all.
“Assume a high income” is not all that helpful.
Unfortunately, exactly what they invested in wasn’t something I was very sensitive to, and I don’t remember it.
Generally, they had fairly ordinary incomes, and they invested in things which were considered low-risk at the time. A fair number of them had real estate in the sense of owning car dealerships (used car lots?), with the land under the business being a large part of their wealth.
They disliked spending money. It was common for them to be men whose wives made a full-time job of running the household cheaply. (There was a later book called The Millionaire Woman Next Door.)
But presumably you have a prior probability distribution over the heritability parameter?
For heritability, I think rationality is closer to reading than it is to intelligence.
How heritable is reading?
For the time being, I’ll just consider literacy as a binary quality, leaving aside differences in ability. In developed countries, with literacy rates around 99%, literacy is probably some what heritable because that <1% cannot read because of some sort of learning defect with a heritable component.
In Mail, with a 26.2% literacy rate, literacy is not very heritable. The illiterate there are a consequence of lack of educational opportunities. I think that the situation we are in regarding the phenotype of “rational” is closer to the Mali scenario rather than the developed world scenario.
You mean in general or for rationality in particular? Lots of things are heritable, to varying (and often disputed) extents. I tend to think genetic factors are often underestimated when explaining human variability. I’m not familiar enough with the evidence for heritability of other high level cognitive abilities to make a very good estimate for the heritability of rationality however.
I’ve just bought What Intelligence Tests Miss for my Kindle after reading the article series here. As I said, I’m skeptical that rationality as an independent factor from IQ is strongly heritable but I’m open to evidence to the contrary which is why I was curious if you had any.
You should still have a prior. “I don’t have enough detailed info” is not an excuse for not having a prior.
Why not just take the probability distribution of heritability coefficients for traits-in-general as your prior?
No, it’s not, but I think it’s a reasonable excuse for not having a more specific prior than ‘low and uncertain’. Being more specific in my prior would not be very useful without being more specific about what exactly the question is. I sometimes see a tendency here to overconfidence in estimates simply because a bunch of rather arbitrary priors have been multiplied together and produced a comfortingly precise number.
I don’t know what it is. I suspect it is not a well established piece of information. I’m not convinced that heritability for ‘traits-in-general’ is a good basis for rationality in particular. Do you have a reference for a good estimate for this distribution?
Here’s a start for you
I feel that people who refuse to give a numerical prior and use protestations of ignorance (that can be cured with a 5-second google search) as an excuse to say “very low” are really engaging in motivated cognition, usually without realizing.
Whenever one says “I don’t have much info so I think the probability of X is really low”, one should ask oneself:
(1) Would I apply the same argument to ~X ? A “very low” prior for X implies a very high prior for ~X. Am I exploiting the framing of using X rather than ~X to engage in motivated skepticism?
(2) Has it even crossed my mind to think about how easy it might be to find the info, and if not, am I willfully clinging to ignorance in order to avoid having to give up a cherished belief?
I never qualified ‘low’ with ‘very’ or ‘really’. If numbers make you feel better ‘low’ means roughly 1-10% probability. I find it a little backwards when someone focuses so much on precisely quantifying an estimate like this before the exact question is even clarified. I see it a lot from non-technical managers as a programmer.
I started this thread by asking for the information you were using to arrive at your (implied) high confidence in a genetic basis for rationality. There’s been several recent articles about What Intelligence Tests Miss and I haven’t started reading it yet (though it is now sitting on my Kindle) so I was already thinking about whether rationality as a separate trait from IQ is a distinct and measurable trait. I haven’t seen enough evidence yet to convince me that it is so your implication that it is and is strongly heritable made me wonder if you were privy to some information that I didn’t know.
While assigning numerical probabilities to priors and doing some math can be useful for certain problems I don’t think it is necessarily the best starting point when investigating complex issues like this with actual human brains rather than ideal Bayesian reasoning agents. I’m still in data gathering mode at the moment and don’t see a great benefit to throwing out exact priors as a badge of Bayesian honor.
of what threshold heritability coefficient?
Really, you should give a set of probabilities: P(H>0.01), P(H>0.02), P(H>0.03),, … P(H>0.98), P(H>0.99).
A reasonable distribution might be some quasi-linear function?
Given that memory, verbal intelligence, spatial reasoning and general intelligence all have values of H of around 0.4, it seems that P{H>0.3) ~ 70%
This is what I meant about quantifying the probability estimate before clarifying the exact question. As I said originally, I’m skeptical of a strong heritability for rationality independent of IQ. I’m not sure what the correct statistical terminology is for talking about this kind of question. I think there is a low probability that a targeted genetic modification could increase rationality independent of IQ in a significant and measurable way. That belief doesn’t map in a straightforward way onto a claim about the heritability of rationality. I’m expecting What Intelligence Tests Miss to help clarify my thinking about what kind of test could even be used to reliably separate a ‘rationality’ cognitive trait from IQ which would be a necessary precondition to measuring the heritability of rationality.
These all correlate significantly with IQ however I believe (correct me if you think I’m wrong on this). It’s at least plausible that targeted genetic modifications could improve say spatial or verbal reasoning significantly more than IQ (perhaps by lowering scores in other areas) since there is some evidence of sex differences in these traits. Rationality seems more like a way of reasoning and a higher level trait than these ‘specialized’ forms of intelligence however.
Maybe. Actually, I think that the dominant theory around here is that rationality is actually the result of an atrophied motivated-cognition module, so perfect rationality is not a question of creating a new brain module, but subtracting off the distorting mechanisms that we are blighted with.
I realize that “brain module” != “distinct patch of cortex real estate”, but have there been any cases of brain damage that have increased a person’s rationality in some areas?
I am aware that depression and certain autism spectrum traits have this property, but I’m curious if physical trauma has done anything similar.
I don’t know, but without a standardized test for rationality (like there is for IQ), how would we even notice?
Googling for “can brain injury cause autism” leads to conflicting info:
To test this, you’d need to somehow identify a group of patients that were going to receive some kind of very specific brain surgery, and give them a pre- and post- rationality test.
At this point I was mostly wondering if there were any motivating anecdotes such as Phineas Gage or gourmand syndrome, except with a noticeable personality change towards rationality. Someone changing his political orientation, becoming less superstitious, or gambling less as a result of an injury could be useful (and, as a caveat, all could be caused by damage that has nothing to do with rationality).
This paper on schizophrenia is interesting.
...because of the following insights ____.
and even then you would only expect 1 in 50 or so kinds of brain surgery to remove the part that caused (say) motivated cognition, and only one in 5 or so of those to not do so much damage that you could actually detect the positive effect.
Better, use high-precision real-time brain imaging to image somebody’s brain when motivated cognition is happening, then use high-precision TMS to switch just that part off.
You can apply laws of probability to intuitive notions of plausibility as well (and some informal arguments won’t be valid if they violate these laws, like both X and ~X being unexpected). Specific numbers don’t have to be thought up to do that.