CHEATERS NEVER WIN Unfaithful is just one example of Hollywood's typically grim take on infidelity

Okay, lightning round. Let's talk about some of the other countries you visited in your research. What's surprising about Russia's infidelity culture?
Russia is the place where infidelity is least taboo. In one survey, 40 percent of Russians said it's never wrong, or only sometimes wrong, compared with 6 percent of Americans who answered the same way. One of the psychologists I interviewed in Russia told me that affairs are obligatory. Others told me that if you lived in a two-room apartment with your entire family and all your in-laws—it's probably a good thing for a person in that situation to have an extramarital relationship.

How about Japan?
Japanese men have an expression: 'If you pay for it, it's not cheating.'

Almost all the Americans I met, when they discovered that their spouse was cheating, they lost a lot of weight. I call it the adultery dietIndonesia?
I expected it to be a very chaste culture. It's the largest Muslim country, and it's not just Muslim nominally—people there are very religious. So I was surprised to find out that, at least among the middle class, it isn't uncommon for married women to have lovers. I met women in veils who text messaged their lovers constantly. SMS is the grease of affairs in Indonesia.

And this even though polygamy is officially sanctioned there.
I thought polygamy would be a container for men's extramarital urges, but if anything it seems to give credence to the idea that men can't be happy with just one woman. Also, if all you want is sexual variety, it's much easier and cheaper to take a lover than to take another wife.

How about South Africa?
A psychologist who worked in a township told me that men came into her clinic complaining of "impotence." That turned out to mean was they couldn't have sex with their mistresses and then go home and have sex with their wives on the same night.

And China?
I was surprised to learn that even working class men in China can now afford to keep second wives. Also, in America, you're supposed to talk about how awful your marriage is if you're a man who's cheating, as a way of justifying it, but in China you're supposed to praise your wife to your mistress. It's how you show you have respect for women.

As I traveled around doing my research, I kept thinking I was going to find this mythical country where people cheat and they're blasé about it, but it turned out that people in every country had quite elaborate and socially acceptable excuses for why they cheat.

What was the most uncomfortable experience you had in your research?
When I was interviewing Hasidic Jews in Brooklyn, one of them began by telling me about the Talmudic laws on adultery. Then he started going into explicit detail about all the things you're not supposed to do, including various forms of lesbian sex.

Was that the guy who asked you to go to a strip club with him?
Yes. He wanted to show me exactly what was forbidden.

FRENCH CONNECTIONS Last Tango in Paris

Did you acquire a knack for spotting infidelity? If you're with a
couple, can you tell if one of them is cheating?
If I had that skill I'd use it on my husband.

Actually, almost all the Americans I met, when they discovered that
their spouse was cheating, they lost a lot of weight. I call it the
adultery diet. I would joke with my husband that if I ever gained a
lot of weight, he would have to have an affair to help me lose it.

Why would they lose weight? To make themselves more attractive, or
just because they're depressed?
Adultery is traumatic everywhere, but in America it's especially so.
People compare discovering their partner's affair to the Twin Towers
collapsing during 9/11, or the Asian tsunami, which killed a quarter
of a million people. "Betrayed spouses," as they're called here, can
take years to recover, and I heard about quite a few attempted
suicides. Their expectations about the world are shattered. There's
kind of no limit to their suffering.

Okay, so Americans in general are horrified by adultery, at least when
the adulterer in question is your spouse. What's more unexpected is
how American filmmakers seem to share this view. You claim that,
in Hollywood movies, extra-marital dalliances lead without fail to
death or disaster. I've tried to think of a counterexample, but I
can't.
Neither can I. People say, "Oh, Hollywood movies glamorize idolatry"
but I found that on the contrary, they make it look like something
that throws your life into chaos. In Hollywood films cheaters are
almost always the villains. Even Borat, who's a flagrant racist and
anti-Semite, doesn't want to risk being a philanderer, too. He only
sets off to conquer Pamela Anderson after he gets a telegram saying
his wife in Kazakhstan has been devoured by a bear.

What's your favorite adultery movie?
"Unfaithful." There's a scene in which the cheating wife and her
friends are sitting around, and one friend says an affair could be a
good idea, like taking a pottery class. One of the other women warns
that it might start out that way, but that it will end up destroying
her life. Wouldn't you know, 40 minutes later the adulteress' husband
murders her lover, and their lives are thrown into disarray.

You got married and had a baby while you were working on this book.
How did that color your view of your subject?
It certainly affected the toasts at our wedding! Seriously, I think it
made the subject less theoretical and more real for me. I had to
really think about how I would react if I discovered my husband was
having an affair.

So how would you react? Differently than you would if you'd never done
this book?
It's a good question. I hope my husband and I are always monogamous,
but I'd like to think that if one of us isn't we'd have the good sense
to respond more like the French. Or like anyone other than Americans.

What will you write about in your next book?
I'm considering some of the other sins. Maybe gluttony.

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