Primates and Philosophers: How Morality Evolved
February 9, 2007

Reviewed by David L. Brooks

Frans de Waal’s latest book stems from the Tanner Lectures he gave at Princeton in 2003, edited and published with comments by a science writer and three philosophers, and with a response by de Waal. Of the many books on evolution and morality out there, this one frames the issues most clearly and is the one book I’d recommend to anyone who wants to get a handle on the subject.

The view of morality de Waal argues against is one which separates morality from nature. This view, which he labels the Veneer Theory, holds that morality is not something that comes from our evolved nature but is something we have created for ourselves: it comes from our reason, not our genes; it comes from our culture, not our nature. It thus separates us from our primate cousins, for whom, under this view, morality is not a possibility, and it separates us from our evolutionary history, for at some point reason and culture gave us the option to be moral, whereas before we were amoral animals like the rest.

Thus the veneer: “Human morality is presented as a thin crust underneath of which boil antisocial, amoral, and egoistic passions” expected of animals. Proponents of the Veneer Theory range from social contract theorists like Thomas Hobbes and John Rawls, to evolutionists like T.H. Huxley, George C. Williams, and Richard Dawkins. That’s quite a line-up!

De Waal argues that this view of morality is false. He points out that “We come from a long lineage of hierarchical animals for which life in groups is not an option but a survival strategy”; and that “there never was a point at which we became social: descended from highly social ancestors—a long line of monkeys and apes—we have been group living for ever.”

Living in groups, being social animals, means that we are naturally moral animals, for we evolved to cooperate, to reciprocate altruism, to “show group loyalty and helping tendencies. These tendencies evolved in the context of a close-knit social life in which they benefited relatives and companions able to return the favor. The impulse to help was therefore never totally without survival value.” Social living depended upon “capacities for reciprocity and revenge, for enforcement of social rules, for the settlement of disputes, and for sympathy and empathy.” And for that, nature equipped our genes.

Thus, de Waal thinks, Veneer Theory gets both the origin and mechanism of morality wrong. Moral behavior is not grounded in culture but in genes. And it was not by reason that we arrived at morality; it was by emotion, especially by sympathy. “Emotions occupy a central role; it is well-known that, rather than being the antithesis of rationality, emotions aid human reasoning. … This is critical for moral choice, because if anything morality involves strong convictions. These convictions don’t—or rather can’t—come about through cool rationality; they require caring about others and powerful ‘gut feelings’ about right and wrong.”

Having laid the conceptual groundwork, de Walls seeks to show that Veneer Theory cannot be correct, and his view of morality is correct, by showing that chimpanzees, our closest primate cousins, behave morally. Here he draws upon decades of close observation of primates and spins many illuminating stories to show that they have “capacities for reciprocity and revenge, for enforcement of social rules, for the settlement of disputes, and for sympathy and empathy.”

De Waal concludes by pointing out that on his view morality it not always something positive and nice. “Morality likely evolved as a within-group phenomenon in conjunction with other typical within-group capacities, such as conflict resolution, cooperation, and sharing.” But this means that morality might not extend to outsiders or to outside groups, and by extension, “the profound irony is that our noblest achievement—morality—has evolutionary ties to our basest behavior—warfare. The sense of community require by the former was provided by the latter.” But this being said, “… we are not hypocritically fooling everyone when we act morally: we are making decisions that flow from social instincts older than our species, even though we add to these the uniquely human complexity of a disinterested concern for others and for society as a whole.”

The commentators attempt to defend reason as the source of morality, or to defend particular versions of Veneer Theory, and this forces de Waal, in his response, to deepen his argument. But he stands by his conclusion that “even if human morality represents a significant step forward, it hardly breaks with the past.”

While such a brief summation cannot do justice to de Waal’s argument, it seems to me that the dichotomy is drawn a little too boldly and the argument laid out a little too simply. And while in one sense a fault, it also allows the issues to be laid out clearly and to bring into bold relief the important points upon which future discussion will turn. I found the book enlightening and entertaining, and I think it makes a wonderful starting place from which to explore the tangled issues of evolution and morality. Highly recommended.

Primates and Philosophers is available from Amazon.com

Sperm Is from Men, Eggs Are from Women
September 29, 2006

The Real Reason Men and Women are Different

by by Joe Quirk
Running Press, 2006

Reviewed by David L. Brooks

The parody in the title catches your eye, as does the name of the author. “What? Another book on the differences between men and women?” you think to yourself. But this, dear reader, is not just another book.

Flip it open and contemplate a sample of the chapter titles:

Female Promiscuity Controls the Size of Your Testicles
What Women Want
When Men Are Afraid of Commitment, Women Cautious about Consummation
How Men Get Sex
The Catfight Gene
The Jerk Gene
Why Women Are Coy, Men Clueless
Why We Bitch
Why You Like Speilberg More than T.S. Eliot
Faked Orgasms Fool Men, but Real Orgasms Fool Women
Why Your Clitoris Is Hard to Find
Broad Hips, Big Butts; Broad Shoulders, Big Diction
Why Your Penis Is Easy to Find
Why Males and Females Don’t Actually Exist
Why Men Have Nipples

Idly turn the pages and read random sentences:

“Virtually everything that goes into making a baby is in the egg. The sperm contributes nothing but genetic material. The rest of the sperm is a delivery system, with a few mitochondria carried along as batteries. Picture a submarine crashing into something the size of San Francisco to deliver one pizza. The pizza is all San Francisco needs to build something the size of the Earth. The submarine disintegrates into the fallopian sea.”

“Natural selection gave man a penis and a brain, but only enough blood to run one at a time. Female emotions are structured to exploit this blood-flow problem.”

“Good bodies and good mothers don’t always go together, which is why every man has a playboy and a father in his genes. Good genes and good fathers don’t always come in the same man, which is why every woman has a concubine and a wife in her genes.”

“Our environment built us to run, breath, eat, squat, throw things, dig for tubbers, and find shelter. But men and women bred each other to be smart, creative, witty, loyal, and beautiful. … Next time you decide to sleep with someone, remember the whole species is at stake. If you have sex with a jerk, you’re selecting for jerk genes.”

“Never forget the evolutionary power of female choice to mold sperm-makers. Remember the principle of the peacock’s tail. If females have some power of mate choice, female tastes will emerge in male bodies and behavior in a few generations.”

“Remember that the noble search for problems and solutions is what caused us to always see the negative side of everything. We owe all our good stuff to our inability to appreciate it. For that we should be grateful.”

“When your genes need you to breed, the last thing they want is you thinking clearly.”

The quotes hardly do the book justice. There is a quotable line on nearly every page and I had to severely cut this review because it was in danger of being as long as the book. In fact, I almost quoted the whole book for this review (that’s still “fair use,” isn’t it?) and then realized that, as I would be adding my own comments and observations, the review would be longer than the book (but also better).

Reading this book is not like attending a seminar in evolutionary psychology given by Leda Cosmides, John Tooby, and David Buss. It’s like having them over for dinner, pouring a little too much wine into them, and then getting a real education.

Witty, fun, and wonderfully informative, you’ll finish this book faster than you finished any book on evolutionary psychology you’ve ever started. And if you’ve never picked up a book on evolutionary psychology, this book will mislead you into thinking that the field is hilariously informative.

But do pick up this book. Homo sapiens are a funny species and this is just the funny book you need to understand what makes them tick.

Highly recommended.

Sperm Are from Men, Eggs Are from Women is available from Amazon.com.

P.S. Hey, Joe! In case you’re reading this: Bembo is cool. Bembo was cut by Francesco Griffo in 1495, for De Aetna, by Cardinal Pietro Bembo. The book was printed Aldus Manutius (the Elder), who also invented italics and was the first to use the semi-colon. So how cool is that? Antique Gothic is one of those 20th century, faux classic faces used by every Tom, Dick, and Carl. Doogie did you right and you got the classier font by far.

The Evolution of Cooperation
September 8, 2006

by Robert Axelrod
Basic Books, 1985

Reviewed by David L. Brooks

You and another player are playing a very simple game. You have before you two buttons: one labelled “cooperate” and one labelled “don’t cooperate.” The other player faces a similar set of buttons. Given that there are two players and two buttons, there are four different payouts. If you both press “cooperate,” you each get, say, $10. If you both push “don’t cooperate,” you each get, say, $2. If you push “cooperate” and the other player pushes “don’t cooperate,” you get nothing and he gets $15, and vice versa should you push “don’t cooperate” while he pushes “cooperate.” The catch is that you must each decide which button to push without being able to see or communicate with each other.

So you try to think it through. What if you push “cooperate”? The other player may likewise push it, and you each get $10. But if he pushes “don’t cooperate,” he’ll get $15 and you’ll get nothing! On the other hand, if you push “don’t cooperate” you may get the $15 (if he’s dumb and trusting enough to push “cooperate”). While if he also pushes “don’t cooperate,” you both get $2, which isn’t much but it’s at least something. So rather than leaving yourself open to the sucker prize of zero, it makes sense to push “don’t cooperate” and get at least $2 and a chance on $15. So you decide not to cooperate.

And since the other player is facing exactly the same situation and is just as rational as you, he also chooses “don’t cooperate.”

This, in a nutshell, is the Prisoner’s Dilemma (PD–so called because it was first presented as a DA making a deal with a couple of criminals), which has long been a mainstay of reasoning about social cooperation. Most of the work had been on single encounters in the PD and the results seemed to show that the logic of such encounters dictated that refusing to cooperate was the rational strategy. This result led to two puzzles. The first was that rational behavior led to sub-optimal results: if you had both cooperated, you would have gained $20 total, but rational behavior lead you both to not cooperate, and you gained only $4 total. The second puzzle was that cooperation did evolve. But, in the light of the logic of the PD, how?

Way back in 1980, the PD was used in experiments in a one-off sort of fashion: two people played once, then they might play once against other people, etc. The suckers quickly learned the error of their ways and very quickly no one cooperated. But Robert Axelrod, thinking strategically, wondered if there might be better and worse strategies if the games were played multiple times against the same player, because, after all, we do meet the same people–your fellow workers, the clerk at the check-out counter, the guy at the dry cleaners–many times, and social cooperation does occur.

In order to make it easy to test, Axelrod announced a computer tournament of an iterated PD and invited experts in game theory to enter by writing a program to be matched against other programs. He got fourteen entries and played them against each other. Although some of the programs were quite elaborate, running to hundreds of lines of code, the simplest program, TIT-FOR-TAT, won. TIT-FOR-TAT had but two rules: cooperate on the first encounter and then do whatever your opponent did the previous move. Axelrod published the results of the contest, including the strategy of the winning program, and announced a second tournament. He got 62 entries from six countries and again TIT-FOR-TAT won.

Here is where the story gets interesting. Instead of thinking strategically, Axelrod began to think in evolutionary terms. Given a population of non-cooperators, could they be invaded by cooperators and under what conditions? Could a population of cooperators resist invasion from non-cooperators and under what conditions? To discover the answers to these questions, Axelrod ran computer simulations using the programs which had participated in the tournament. His conclusions throw a fascinating light on the evolution of cooperation, showing that cooperators can invade populations of non-cooperators with as little as 5% of the population, while populations of cooperators are stable against invasion by non-cooperators.

Axelrod analyzes the results of the tournaments and derives four simple rules that distinguished those programs that did well from those that failed. He then applies these rules to the real world to show how the live-and-let-live system evolved on the Western Front during WWI and, in a chapter with William D. Hamilton, he examines the evolution of cooperation in biological systems.

Altogether, this simply-written and much-discussed book has profoundly impacted our view of cooperation in nature. If you haven’t yet, you really need to read this book.

Highly reccommended.

The Evolution of Cooperation is available from Amazon.com.

No Two Alike: Human Nature and Human Individuality
August 4, 2006

by Judith Rich Harris
W.W. Norton & Co., 2006

Reviewed by David L. Brooks

Why do people differ in personality? That’s obvious: people have different genes.

This is true but it actually raises a more difficult problem. Averaging the results of numerous studies reveals that genes only account for about 45% of the difference in personality. Take identical twins; they share the same set of genes, yet they differ in personality even when raised in the same home. But the problem goes even deeper than that. As Harris points out:

The unexplained—that is, nongenetic—differences in personality between identical twins reared in the same home are about as wide as the unexplained differences between ordinary siblings. And the unexplained differences between ordinary siblings are about as wide as the unexplained differences between two people of the same sex and about the same age, plucked at random from a city street or college classroom.

So what accounts for the unexplained (nongenetic) differences in personality? Many answers have been offered: children grow up in different environments; they have different home environments and grow up with parents who have different styles of child rearing; although twins share the same genes, they grow up in slightly different environments and hence their gene-environment interactions are different; a child is either an only child or, if siblings are present, is a younger or older child, i.e., birth order matters even for identical twins; individuals to some extent make their own environments so that sweet children are treated differently than cranky children, and active children are treated differently than passive children.

These five hypotheses are currently the most popular explanations offered by developmental psychologists for why children grow up to have different personalities. Harris spends the first half of her book demolishing each of these explanations (and embarrassing a couple of developmental psychologists) with incisive logic and impressive research.

Having cleared the ground, Harris sets out to answer the question: why do people, even identical twins raised in the same home, differ in personality? To do so, she takes a stand in evolutionary psychology and rather than treat the brain as a single organ, she treats it as a system of organs, each evolved to solve a particular problem our ancestors faced.

Harris hypothesizes that three systems in the brain play a part in personality development, each of which is necessary for a child to become a human being capable of living with other human beings. The first is relationship system, which is ready to go at birth and which continues its job throughout our lives. The relationship system establishes and maintains relationships. The second system is the socialization system, which is working by the age of three and had largely completed its work by adolescence. The function of this system is to turn an individual into a member of a particular group—the group the child finds itself in. The third system is the status system, which begins to be seen in the competitiveness of three-year-olds but which develops slowly, is most active in adolescence and young adulthood.

It is fascinating to watch Harris weave the elements of her explanation together. Deep knowledge of the relevant literature, incisive logic, and lucid prose make this a worthy successor to The Nurture Assumption.

Highly recommended.

Buy It!