Nicholas Wade's new book Before the Dawn offers a fascinating review of recent science in human prehistory.  Genetic analysis of human remains can now tell us a lot about how humans spread across the world, starting about 50,000 years ago.  But one aspect of the book is a bit puzzling.  Every chapter has an epigraph from Charles Darwin's Descent of Man, and not just a few words, but a paragraph that takes up most of the page.

What is going on here?

Arnold Kling has the answer.  The Darwin epigraphs are "trust cues."

Nicholas Wade is a science reporter at The New York Times, and his book advertises news of scientific discoveries that might not go down well with his liberal readers.  For instance, it turns out that chimpanzees are not quite the peaceable souls that decades of National Geographic specials have represented to us.  Your average adult male chimpanzee likes nothing better than an aggressive border raid into the territory of the neighboring troop.  The usual order of battle is for three chimps to set off into enemy territory and find a solo chimp feeding away from the rest of the troop.  When they have caught their prey, two of them hold the victim down while the third kills it.

That might explain why humans have been so warlike over the years.
About 65 percent of primitive societies are at war constantly, Wade writes, and about 30 percent of males die from conflict.  The dawn raid is a favorite human tactic.  You enter an enemy village at dawn, set fire to the huts, and then kill people as they run out of the burning huts to safety.

Wade tells his readers other disturbing facts.  Genetic analysis strongly suggests that all men are descended from a single male, and all women from a single female.  On top of that, race is clearly genetic in origin, and not a "social construct" as the American Sociological Association insists.

With all this unwelcome news to print, Wade and his publisher did the sensible thing.  They put a Darwinian devotional at the top of every chapter.  They knew that even though their readers proudly read The New York Times Science Tuesday every week, they really don't like science once it moves out of the tenured university laboratory into reality.  They are all for science until it interferes with their politics.  But they all believe in Darwin.

How can we demand peace and justice if every man living has the instinctive need to conduct a nice little border raid next week?  How can we stamp out racism if race is imprinted in the genes?  And how can we justify tossing  pushy Jews like Larry Summers out of their Harvard presidencies if there really are physical, measurable brain differences between men and women?

These are inconvenient truths, and good reasons to put comforting "trust cues" into Before the Dawn to remind readers that you are really on their side.

Conservative married women are into trust cues too.  They realize that a rational world of freedom and contract is not enough to raise healthy babies.  What babies need beyond material things like milk and warmth are trust cues to teach them that they can trust that mother will always be there to take care of them.  And father too. That is what Jennifer Roback Morse writes in Love and Economics. It was a hard lesson for her, a tenured professor of economics, to learn.

Economics is all about rational calculation: self—interest, rightly understood.  Economists believe in the application of reason to economic relationships: equal and reciprocal rational agreements in contract.

When you have a contract, then you can break it.  But what babies need, and what mothers need, is an unbreakable contract.  You can't get that with rational, calculating mothers and fathers, the kind that can do a Prisoner's Dilemma analysis at every moment, calculating whether it is it their interest to be trustworthy or to cheat.  As Morse writes: when someone calculates whether it is worthwhile to cheat, the game is over.  That person will eventually cheat. 

"The person who never [cheats] is the person who never begins the calculation." 

How would you deal with these cheaters and freeloaders?

Nicholas Wade writes:

"Human societies long ago devised an antidote to the freeloader problem...  It is religion."

Now it's a curious thing, is it not, that in our current secular society, in particular at the epicenter of secularity, Western Europe, we are having a real problem persuading people to have babies.  Why would that be, do you think?

Perhaps in the low—trust society of secular Europe people just don't get the trust cues they need before they will take the risk of having children.

Maybe they need to get away from rational self—interest and learn from Dr. Morse about "self—giving, rightly understood."

Christopher Chantrill blogs here. His Road to the Middle Class is forthcoming.