Bryan Caplan  

Love and Economics: A Guide from the Perplexed

Great Lines from Bob Solow... Tyler Cowen and Robin Hanson...
Jennifer Roback Morse was almost my colleague - she left the Public Choice Center in 1996, a year before GMU hired me.  She's a libertarian economist, a blogger, and passionate about the economics of the family.  I've only met her once (at a party at Larry Iannaccone's house), but you'd think that we'd have a lot in common.  Unfortunately, I walked away from Morse's Love and Economics: Why the Laissez-Faire Family Doesn't Work thoroughly perplexed.

My overarching question: How can a 21st-century social scientist publish a book about the family without even mentioning* the possibility that nature, not nurture, accounts for the greater success of kids raised in traditional homes?  In 1960, a scholar might point out that children of divorce, single moms, or working moms do worse, and infer causation.  In 1980, a scholar might tighten up the case by controlling for income, race, and so on.  But by 2001 - the year Love and Economics appeared - genetically informed designs using twins or adoptees were already the gold standard of serious research.  And research using these methods has a strong tendency to find that nature does indeed crush nurture, especially in the long-run.  Contra Morse, the best evidence (see Harris, Pinker, and Segal for starters) shows that as far as kids are concerned, the "laissez-faire family" does indeed work about as well as the competition.

The emotional anchor of Morse's book is her experience adopting a neglected Romanian orphan.  She movingly describes the awful treatment he endured during his early years, and his need for a full-time mom to get him back on track.  She could easily be right that a "laissez-faire family" wouldn't have worked for her son.  The twin and adoption studies scholars rely on rarely include severely deprived children, so the standard result that nature dominates nurture in the long-run might not apply. 

But Morse doesn't just want to carve out an exception for kids like her adopted son.  Instead, she wants to generalize from severely deprived kids to mundane departures from the traditional family like divorce, single motherhood, and moms with full-time jobs.  The data from twin and adoption studies just won't let her get away with that.

* There's one entry in the index for genetics, but the entry refers to the sociobiological argument that men are less likely to abuse their biological children, not the behavioral genetic point that your biological children will resemble you in many ways whether or not you ever meet them.

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The author at Jim's Blog in a related article titled The problems with Laissez Faire sexuality. writes:
    Bastards are bastards. The production of bastards creates large external costs. ... [Tracked on March 16, 2009 10:15 PM]
The author at Remaking Modern Society in a related article titled Can a Laissez-Faire Family Work? writes:
    Does nature determine the success of our children, or can we nurture any homeless boy to become the next superhero? Bryan Caplan knows the answer, striking out against Jennifer Roback Morse's latest book on the modern family: My overarching question: How [Tracked on March 17, 2009 2:32 PM]
COMMENTS (11 to date)
Brad Taylor writes:

It's a bit of a stretch to call her a "libertarian economist", surely. She's very much a conservative now, as far as I can tell. She likes the market, but seems to be all for government favouring traditional ways of life.

I do think her earlier work on segregation is excellent, by the way.

Steve Sailer writes:

Sure, but you're missing the point about how laissez-faire families affect the genes that children wind up with.

Identical twin Jane marries a boring guy with a job and they have a few kids who grow up to be job-holding non-criminal taxpayers.

Her identical twin Joan gets impregnated by various sexy guys who shortly thereafter get shot, imprisoned, or vanish. Her kids grow up to be sexy, unstable individuals.

A traditional society encourages more women to marry stable breadwinner. A 21st Century society encourages women to indulge their hormones. The smarter ones figure out what's in their best interests, but the dumber ones don't.

Mike writes:

Yeah, I don't recall her being libertarian, and if anything, she seems to have become much more conservative over the years.

Michael from Ireland writes:

I cannot comment on the book under review, since have not read it. Yet I'd like to comments on what Mr. Caplan wrote, from my own experience.

Firstly, my wife is a qualified interior designer. I am a qualified architect of more than 15 years experience. Our son [9] has some artistic ability, good eye, colour sense etc. He can put thoughts on paper as abstract concepts if the mood takes him. But he doesn't spend 2 hours a day drawing like I used to, he plays his DS lite.

Secondly, I cannot speak as a twin, or even as an adopted child with full siblings. I can however speak as an adopted child with several cousins. I began learning about them recently recently. None of my cousins have shown an inclination towards art or architecture.

That's in a country like Ireland where architecture can run in families. I have seen people with vastly different abilities come from the same family. I have also seen some who should not have chosen architecture as their career.

The point being that my mother's nurturing of my ambition was a huge factor. My adopted mother, that is, who was "merely" a home-maker, not a professional. And it was my wife's parents nurturing of her talents that led to her own career.

So, yes, you can have "bad seeds" in a family, which will come out despite nurture. But no, tendencies, even career-shaping tendencies might not shape a life. But in general supportive nurture in a secure home setting makes the best of us.

Ian Dunois writes:

I have sat in a few of her lectures on this topic. In the lecture, she had given a story of a friend whose adopted son ended up stealing cars and ended up in jail. The mother sighed a sigh of relief and when questioned about it stated, "I raised him to the best of my abilities, and thankfully, he is only a car thief and not a murderer."

From what I took from her lectures was not that nurturing is the most important factor, only that it is a factor. I believe her work means to bring an argument to why society needs to begin building strong families beginning with the relationships between the parents.

In short, she is a God fearing woman who wants to show why it is the commandment of love your father and mother is so important.
Through her work she displays not only the importance of having a mother in a child's life (something we all heard about growing up and reason why most divorce cases end with the mother having possession of the children), but also the importance of a father in a child's upbringing.

Steve Roth writes:

Thanks, Bryan. I won't bother with that book.

On the topic, though, the most profound paper I've read recently is Turkheimer et. al, "Socioeconomic Status Modifies Heritability of IQ in Young Children."

From the paper: "in impoverishehd families, 60% of the variance in IQ is accounted for by the shared environment, and the contribution of genes is close to zero; in affluent families, the result is almost exactly the reverse."

What this says to me: the nurturance bar is quite high for human beings to live out their innate genetics. It's not just about "severely deprived" children; they need pretty good standard of (to use a plant metaphor) sun, water, space, and fertilizer to avoid being stunted or--in the extreme--twisted.

Robert Book writes:
Instead, she wants to generalize from severely deprived kids to mundane departures from the traditional family like divorce, single motherhood, and moms with full-time jobs.


Maybe full-time jobs (depending on duration and age of the kids at the time), but do you seriously believe that divorce and (from birth) single motherhood are merely "mundane" departures?

Isn't there a substantial body of evidence on adverse effects on children of divorce? (At least, emotional and psychological effects.) Didn't these effects become more common as divorce became more common, indicating a significant role for "nurture"?

Could that be comparable to the effects of income in the Turkheimer et. al. paper cited above?

Hi Everyone,
I appreciate people's comments on my work. I especially appreciate Bryan's alerting me to the fact that he had posted on Love and Economics.
I am not overly concerned about Bryan's original critique for these reasons:
1. the work on genetics that he cites has mostly to do with personality traits, which I am perfectly willing to believe have a large genetic component. the concern of my book has to do with the development of the conscience, which is absolutely necessary for a free society, and which has a HUGE relational component.

2. I cite numerous studies showing the negative impact of family fragmentation on the well-being of children. Most of those studies hold constant income and education of parents, which is (an admittedly crude)proxy for genetic endowment. Even holding constant income and education, children of divorce, for instance, experience more anxiety and depression, have poorer school performance, are less trusting and are less likely to get married themselves.
There was a study in Sweden in 2003, which I cited in my second book, Smart Sex. This study held constant income, education and the mental health history of the parents. They still found that children in single parent households were twice as likely to use drugs, or alcohol, or to attempt suicide. the results, as I recall, were particularly pronounced for boys.

3. the most sophisticated research is now showing that the old dichotomy between nature and nurture is ill-conceived. Matt Ridley has a book called "Nature via Nurture," whose title sums up the newer thinking. People can have genetic predispositions for traits that are triggered by something in the environment.

4. a very interesting book along these lines is A General Theory of Love, which shows that every relationship is a physiological event. (not all physiological things are genetic, by the way.) The most obvious example is that an infant's growth hormones are stimulated by the presence of, and touch from, an adult. I did not cite this in Love and Economics, because I only discovered it later. But I do cite it in Smart Sex.

5. it would be extremely odd for a person to take a genetically based position that a mammalian species with long period of infant dependency does not benefit from parental inputs or from parental cooperation. yet that seems to be the implied position that Bryan originally takes. i can't believe he means it.

6. finally, the overall point of the book is that the preservation of freedom requires the family to bring helpless infants to the point of adult independence. i conscientiously believe that when the family falls apart, or fails to form, the state steps in, and expands. does anyone on this list seriously deny this? Big Government Leftists have spent an enormous amount of energy breaking apart the conjugal pair. I think, as they say, that this is no accident. The Left realizes that the family, functioning as an independent entity apart from the state, actually limits the state. This is why I still consider myself an advocate of minimum government, even though I guess the libertarian label doesn't exactly fit as well as it used to. But I think it is foolish to deny that children require some special analysis and care from us. I think one can be a more consistent and coherent advocate of minimum government by facing squarely the fact of infant dependency and the significance of parental inputs.

But I have gone on too long! Thanks for taking my work seriously enough to critique.

Bob Murphy writes:

I confess I haven't read the literature, but I refuse to believe that "parents don't matter." I'm not sure if that's what Bryan is saying, but I'm pretty sure that's what Levitt said in Freakonomics.

I am prepared to accept that what we think parents are doing, is not the real mechanism. But when someone says, "This research shows that parents don't determine whether their kids are good students" I believe that as much as studies that "prove" socialism worked in country X.

Mike writes:

Even holding constant for income, education, mental health etc. there is surely going to be large unobservable heterogeneity between parents that divorce and parents that do not. Further, there may even be important endogeneity problems (i.e. a problematic kid increases the likelihood of divorce, making causality also go the other way around).

A couple of years back I scanned quite a lot of the literature on the topic, and if I remember correctly it is better to grow up with single-mother/single-father (with only one or shared custody) compared to growing up in a family where the parents are unhappy, arguing and have a general unhealthy relationship.

I have no problems believing that it is beneficial to grow up with both your parents if they have a healthy relationship. But, the problem is of course that often the choice is between having shared custody or between staying together in a messy unhealthy relationship. I think there is good evidence that in such cases, breaking up may be marginally beneficial for the kid.

I don't know what you read, but that is not the consensus of the literature. Take a look at Paul Amato's book, A Generation at Risk. He specifically separates children in "low conflict" marriages from those in "high conflict" marriages. Kids in high conflict marriages, ie domestic violence, drug abuse, etc, are better off if their parents divorce. But children in low conflict marriages are better off if their parents stay married.
The problem is less than a third of marriages could be classified as "high conflict" and that no-fault divorce really revolutionized the behavior of couples in low conflict marriages. That is, low conflict marriages are precisely the ones in which people used to "stay together for the sake of the kids," and which now end in divorce. (BTW, under the fault-based rulese, most high conflict marriages would have qualified as having "cause" for divorce in most jurisdictions.)

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