The Human Mind

Voter Rationality

Posted by Peter on November 19, 2006
Posted in: Politics, The Human Mind. Tagged: , .

Bryan Caplan has a good post arguing democracy produces worse results than rational ignorance among voters would explain.
However, one aspect of his style annoys me – his use of the word irrationality to describe what’s wrong with voter thinking focuses on what is missing from voter thought processes rather than what socially undesirable features are present (many economists tend to use the word irrationality this way). I hope his soon-to-be-published book version of this post devotes more attention to what voters are doing that differs from boundedly rational attempts at choosing the best candidates (some of which I suspect fall into what many of us would call selfishly rational motives even though economists usually classify them as irrational). Some of the motives that I suspect are important are the desire to signal one’s group membership, endowment effects which are one of the many reasons people treat existing jobs as if they were more valuable than new and more productive jobs that can be created, and reputation effects where people stick with whatever position they had in the past because updating their beliefs in response to new evidence would imply that their original positions weren’t as wise as they want to imagine.
Alas, his policy recommendations are not likely to be very effective and are generally not much easier to implement than futarchy (which I consider to be the most promising approach to dealing with the problems of democracy). For example:

Imagine, for example, if the Council of Economic Advisers, in the spirit of the Supreme Court, had the power to invalidate legislation as “uneconomical.”

If I try hard enough, I can imagine this approach working well. But it would take a lot more than Caplan’s skills at persuasion to get voters to go along with this, and it’s not hard to imagine that such an institution would develop an understanding of the concept of “uneconomical” that is much less desirable than Caplan’s or mine.

Social Mindscapes

Posted by Peter on November 2, 2006
Posted in: Book Reviews, The Human Mind.

Book review: Social Mindscapes: An Invitation to Cognitive Sociology by Eviatar Zerubavel
This book is a refreshing and concise collection of interesting tidbits about cultural aspects of human minds. He points out many cultural quirks in our thinking that I suspect many people unconsciously assume are universal beliefs. Sometimes it’s easy to see once you’re provoked to think about it why we should consider something to be a cultural quirk (e.g. putting jam and jelly into two distinct categories rather than one). With others, such as whether the differences between male and female genitalia justify classifying the equivalent parts differently for each sex, I’m almost suspicious enough of his report that western culture had a different answer a couple of centuries ago than it does today to tempt me to check some of his copious references. And there are a few places where his cultural norms seem odd (e.g. his claim that daylight savings time seems natural).
With only 113 pages of actual text, it’s a quick read that would be worth reading for the entertainment value alone, and has the added benefit of shaking up one’s preconceptions.

Singing Neanderthals

Posted by Peter on October 26, 2006
Posted in: Book Reviews, The Human Mind. Tagged: , .

Book Review: The Singing Neanderthals: The Origins of Music, Language, Mind, and Body by Steven Mithen
This book presents some interesting and refreshing speculations on how music and language evolved, emphasizing reasons for believing that music was at least as important as language during significant parts of human evolution. It stretches the limits of what we can figure out from the available evidence, so it’s likely the some of it is wrong. But his hypotheses appear more likely to help us ask the right questions than to lead us astray.
Mithen’s knowledge of archeology helps make his book different from most books about the human mind in that he emphasizes very different selective pressures at different stages in human evolution, corresponding to changes in conditions that our ancestors faced.
Here are some surprising and informative section titles that will tell you something about the flavor of the book: “The musical implications of bipedalism”, and “The sexy hand-axe hypothesis”.
I was intrigued by his description of how music helps a group cooperate by synchronizing their emotions. But he helps point out the limits of those benefits by noting that the chants at Nazi rallies that helped unite most of the German people.

Happiness

Posted by Peter on October 11, 2006
Posted in: Book Reviews, The Human Mind. Tagged: , .

Book Review: Happiness: The Science behind Your Smile by Daniel Nettle
This book provides a fairly good, but not very novel, description of what does and does not influence happiness, the problems with measuring it, and some bits of evolutionary theory that hint at why it is hard to achieve lasting increases in happiness.
The claim I found most important is that “If you control for social class, there is almost no relationship between income and life satisfaction.” This seems to have important implications for what kind of social equality we ought to be encouraging. I’m disappointed that he doesn’t say enough about this for me to determine how robust this conclusion is to the way it’s measured.
I’m disappointed that he ends with some misleading arguments for an alarming trend of increased distress among the least happy. He reports that suicides have increased among the young in recent decades, but fails to note that overall suicide rates in the U.S. have declined over that period. He claims “People are as hard as they ever have”, but cites no references for that, and Robert Fogel has reported research that reached the opposite conclusion in The Escape from Hunger and Premature Death.

No Two Alike

Posted by Peter on October 3, 2006
Posted in: Book Reviews, The Human Mind. Tagged: , .

Book review: No Two Alike: Human Nature and Human Individuality by Judith Rich Harris
This book provides a clear theory of what causes the personality differences between people that can’t be explained by genetic differences. She focuses a fair amount on identical twins, because the evidence that their environmentally caused personality differences are the same as ordinary siblings, and the same whether they’re reared together or apart, rules out many tempting theories.
Amazon reviewer Sioran points out an inconsistency – she claims early on that random chance can’t explain all of the variation, but her explanation ends up amounts to saying the causes are ultimately random. I find her early arguments against randomness unconvincing. And her explanation’s reliance on randomness doesn’t imply that her explanation is useless – she rules out most kinds of randomness as a cause, narrowing down the class of random causes to those which affect the person’s view of her status in society (e.g. differences in who outside family the person interacts with, and physical differences such as being tall due to better nutrition).
The most surprising prediction she makes is that mindblind (i.e. most) animals won’t have persistent personality differences that can’t be explained by genetic differences. I’m unsure whether to believe this – it seems that animals should only need to remember differences in how others treat them (rather than have a theory of mind) in order to produce the results we see. She would probably predict that autistic people have no persistent environmentally caused personality differences, but she isn’t clear about that (it may depend on the degree of autism).
One interesting result that she mentions is that autistic children are unable to use the fusiform face area (which in most people is specialized to do good face recognition), and instead seem to recognize faces the same way they recognize ordinary objects. I’m wondering how much this explains about why autism impairs many parts of the mind that deal with relationships.
I’m annoyed by how many pages she spends recounting the reaction to her prior book (The Nurture Assumption, a better book than this). If you’ve read that, most of the first half of this book will be a waste of time.
One interesting piece of evidence she mentions is this paper from the Journal of Political Economy which says that one’s height as a teenager is a better predictor of wages as an adult than adult height.
One small quibble: she says being a firstborn is unimportant (often not even known) outside the home in “contemporary societies — at least those not ruled by monarchies”. Korean society appears to be a clear exception to that claim.

Evolution’s Rainbow

Posted by Peter on September 20, 2006
Posted in: Book Reviews, Politics, The Human Mind. Tagged: , .

Book review: Evolution’s Rainbow: Diversity, Gender, and Sexuality in Nature and People by Joan Roughgarden
This book provides some good descriptions of sexual and gender diversity in nature and in a variety of human cultures, and makes a number of valid criticisms of biases against diversity in the scientific community and in society at large.
Many of her attempts to criticize sexual selection theory are plausible criticisms of beliefs that don’t have much connection to sexual selection theory (e.g. the belief that all sexually reproducing organisms fall into one of two gender stereotypes).
Her more direct attacks on the theory amount to claiming that “almost all diversity is good” and ignoring the arguments of sexual selection theorists who describe traits that appear to indicate reduced evolutionary fitness (see Geoffrey Miller’s book The Mating Mind). She practically defines genetic defects out of existence. She tries to imply that biologists agree on her criteria for a “genetic defect”, but her criteria require that a “trait be deleterious under all conditions” (I suspect most biologists would say “average” instead of “all”), and that it reduce fitness by at least 5 percent.
Her “alternative” theory, social selection, may have some value as a supplement to sexual selection theory, but I see no sign that it explains enough to replace sexual selection theory.
She sometimes talks as if she were trying to explain the evolution of homosexuality, but when doing so she is referring to bisexuality, and doesn’t attempt to explain why an animal would be exclusively homosexual.
Her obsession with discrediting sexual selection comes from an exaggerated fear that the theory implies that most diversity is bad. This misrepresents sexual selection theory (which only says that some diversity represents a mix of traits with different fitnesses). It’s also a symptom of her desire to treat natural as almost a synonym for good (she seems willing to hate diversity if it’s created via genetic engineering).
She tries to imply that a number of traits (e.g. transsexualism) are more common than would be the case if they significantly reduced reproductive fitness, but her reasoning seems to depend on the assumption that those traits can only be caused by one possible mutation. But if there are multiple places in the genome where a mutation could produce the same trait, there’s no obvious limit to how common a low-fitness trait could be.
Her policy recommendations are of very mixed quality. She wants the FDA to regulate surgical and behavioral therapies the way it regulates drugs, and claims that would stop doctors from “curing” nondiseases such as gender dysphoria. But she doesn’t explain why she expects the FDA to be more tolerant of diversity than doctors. Instead, why not let the patient decide as much as possible whether to consider something a disease?

Stumbling on Happiness

Posted by Peter on September 12, 2006
Posted in: Book Reviews, The Human Mind. Tagged: , , , .

This book is a colorful explanation of why we are less successful at finding happiness than we expect. It shows many similarities between mistakes we make in foreseeing how happy we will be and mistakes we make in perceiving the present or remembering the past. That makes it easy to see that those errors are natural results of shortcuts our minds take to minimize the amount of data that our imagination needs to process (e.g. filling in our imagination with guesses as our mind does with the blind spot in our eye).
One of the most important types of biases is what he calls presentism (a term he borrows from historians and extends to deal with forecasting). When we imagine the past or future, our minds often employ mental mechanisms that were originally adapted to perceive the present, and we retain biases to give more weight to immediate perceptions than to what we imagine. That leads to mistakes such as letting our opinions of how much food we should buy be overly influenced by how hungry we are now, or Wilbur Wright’s claim in 1901 that “Man will not fly for 50 years.”
This is more than just a book about happiness. It gives me a broad understanding of human biases that I hope to apply to other areas (e.g. it has given me some clues about how I might improve my approach to stock market speculation).
But it’s more likely that the book’s style will make you happy than that the knowledge in it will cause you to use the best evidence available (i.e. observations of what makes others happy) when choosing actions to make yourself happy. Instead, you will probably continue to overestimate your ability to predict what will make you happy and overestimate the uniqueness that you think makes the experience of others irrelevant to your own pursuit of happiness.
I highly recommend the book.
Some drawbacks:
His analysis of memetic pressures that cause false beliefs about happiness to propagate is unconvincing. He seems to want a very simple theory, but I doubt the result is powerful enough to explain the extent of the myths. A full explanation would probably require the same kind of detailed analysis of biases that the rest of the book contains.
He leaves the impression that he thinks he’s explained most of the problems with achieving happiness, when he probably hasn’t done that (it’s unlikely any single book could).
He presents lots of experimental results, but he doesn’t present the kind of evidence needed to prove that presentism is a consistent problem across a wide range of domains.
He fails to indicate how well he follows his own advice. For instance, does he have any evidence that writing a book like this makes the author happy?

Kanzi

Posted by Peter on July 25, 2006
Posted in: Book Reviews, Science and Technology, The Human Mind.

Book Review: Kanzi: The Ape at the Brink of the Human Mind by Sue Savage-Rumbaugh
This book makes plausible claims that some bonobos have learned to handle language in a way that is approximately as sophisticated as that of a two year old human. But their anecdotal evidence is somewhat hard to evaluate, and they didn’t quite convince me that they were careful enough to rule out the possibility that their biases caused them to overestimate the sophistication of Kanzi’s understanding.
The book is a bit long-winded about research that Savage-Rumbaugh did before working with Kanzi, and I was a bit disappointed that the book didn’t provide more of the anecdote about Kanzi that made the book worth reading. But those anecdotes convinced me that much more is going on than some authors such as Pinker had led me to believe. I still hope for better evidence that will help clarify how much bonobos can understand. But that will be hard, and I don’t know how it should be done.

Race, Evolution, and Behavior

Posted by Peter on May 11, 2006
Posted in: Book Reviews, Politics, The Flynn Effect, The Human Mind. Tagged: , , .

Book Review: Race, Evolution, and Behavior: A Life History Perspective by J. Philippe Rushton
Rushton has a plausible theory that some human populations are more k-selected than others. He presents lots of marginal-quality evidence, but that’s no substitute for what he should be able to show if his theory is true.
Much of the book is devoted to evidence about IQs and brain sizes, but he fails to provide much of an argument for his belief that k-selected humans ought to have higher intelligence. It’s easy to imagine that it might work that way. But I can come up with an alternative based on the sexual selection theory in Geoffrey Miller’s book The Mating Mind that seems about as plausible: r-selected humans have more of their reproductive fitness determined by success at competition for mates (as opposed to k-selected humans for whom child support has a higher contribution to reproductive fitness). Since The Mating Mind presents a strong argument that human intelligence evolved largely due to such competition for mates, it is easy to imagine that r-selected humans had stronger selection for the kind of social intelligence needed to compete for mates. Note that this theory suggests the intelligence of k-selected humans might be easier to measure via standardized tests than that of r-selected humans.
Rushton’s analysis of the genetic aspects of IQ makes the usual mistake of failing to do much to control for the effects of motivation on IQ scores (see pages 249-251 of Judith Rich Harris’s book The Nurture Assumption for evidence that this matters for Rushton’s goals).
He also devotes a good deal of space to evidence such as crime rates where it’s very hard to distinguish genetic from cultural differences, and there’s no reason to think he has succeeded in controlling for culture here.
Rushton mentions a number of other traits that are more directly connected to degree of k-selection and less likely to be culturally biased. It’s disappointing that he provides little evidence of the quality of the data he uses. The twinning data seem most interesting to me, as the high twin rates of the supposedly r-selected population follow quite clearly from his theory, it’s hard to come up with alternative theories that would explain such twinning rates, and the numbers he gives look surprisingly different from random noise. But Rushton says so little about these data that I can’t have much confidence that they come from representative samples of people. (He failed to detect problems with the widely used UN data on African AIDS rates, which have recently been shown to have been strongly biased by poor sampling methods, so it’s easy to imagine that he uses equally flawed data for more obscure differences). (Aside – the book’s index is poor enough that page 214, which is where he lists most of his references for the twinning data, is not listed under the entry for twins/twinning).
Rushton occasionally produces some interesting but irrelevant tidbits, such as that Darwin “affirmed human unity” by ending the debate over whether all humanity had a common origin, or that there’s evidence that “introverts are more punctual, absent less often, and stay longer at a job”.
Edward M. Miller has a theory that is similar to but slightly more convincing than Rushton’s in a paper titled Paternal Provisioning versus Mate Seeking in Human Populations.

Adapting Minds

Posted by Peter on March 6, 2006
Posted in: Book Reviews, The Human Mind. Tagged: , .

Book Review: Adapting Minds : Evolutionary Psychology and the Persistent Quest for Human Nature by David J. Buller
This book makes a strong case that there are problems with claims put forth by leading Evolutionary Psychologists, but the problems are somewhat less important than the book tries to imply.
This is the most serious and careful attack on Evolutionary Psychologists so far. But it is often hard to tell to what extent the theoretical claims he attacks are reflect bad theories or whether some of them are just careless misstatements by people who are too focused on attacking the tabula rasa worldview to worry about criticisms from other viewpoints. For instance, it’s hard to believe that the Evolutionary Psychologists mean the word “universal” in the phrase universal human nature as literally as Buller takes it.
He presents strong arguments that Evolutionary Psychologists have overstated the extent to which dna encodes specialized mental modules, and presents detailed arguments that their empirical results have been sloppy and at least slightly biased against the idea of a general-purpose mind. But if Evolutionary Psychologists are willing to modify their theory to refer to somewhat less specialized modules whose features are influenced by dna in less direct and more subtle ways, then the features of their theories that they seem to consider most important will survive.
His analogy with the immune system illustrates how a system that looks at first glance like it requires some fairly detailed genetic blueprints can actually be caused by a general purpose system that learns most of its specializations by reacting to the environment.
This is not in any way an attack on the idea of using evolutionary theory to understand the mind. In fact, he even points out that Evolutionary Psychologists have been overly interested in questions asked by creationists rather than those that evolutionary theory suggests are important.
Ironically for a philosophy professor, his weakest arguments are the most philosophical ones. He correctly points out the problems with using an essentialist notion of species that is based on universal phenotypic characteristics, but then proposes a definition of species based on continuity and spatiotemporal localization that seems as essentialist and as far from what people actually mean by the word as the definition he criticizes. If I understand his definition correctly, it implies that recreating a Dodo from dna would produce a new species. He should study the philosophy of concepts a bit more (e.g. Lakoff or the neural net literature) and decide that the concept of species doesn’t need either type of essence, but can instead be a more probabilistic combination of several kinds of attributes.