BEFORE I MOVED OUT, before I lost the ability to go forward in what had been a long and rich and difficult and painful and profoundly rewarding marriage with three great children — to put the matter more precisely, before I lost the strength and the desire to try to be the person I was supposed to be and hide the one I’d become — I asked my wife: “Why do men lie so much?” I can see now that the long pondering I ’d been doing on the subject of men and lies was a circling-the-airport approach to where I might land, which was my own conscience.

“Your sperm makes you evil,” my wife said. “It does something to your minds.”

“No, seriously,” I said.

“Because you’re all cowards,” she said.

“That’s a little too serious,” I said. “Do you have anything in between those two?” “In between the two,” she said, “is just a charred landscape.”

There are things that everyone almost always lies about (cheating, stealing, sex), there are things that women almost always lie about (food, money, orgasms), and then there is the rest of life, which generally comprises what men lie about. A female friend says of the men she’s known: “Are its lips moving? Then it’s lying.”

I’m talking about the issue later at a party with a fellow I’ve met; he plays high-stakes poker, sometimes for a living, other times merely competitively. Someday, it’s my guess, he’ll get close to a woman who doesn’t want him to play this kind of poker or, in fact, since this is the only kind of poker that he’s interested in playing, any poker at all. He’ll promise not to, and then he’ll join the eternal cycle.

“Men pretty much always lie to avoid conflict, argument, the airing of unpleasant truths,” he says, in a jovial, unmarried way. “It’s been my impression that both parties are pleased with the outcome.”

He’s half right: to avoid unpleasantness is one reason we lie, a frequent reason, but not “pretty much always” the reason. Another woman, married, hearing the topic, says: “You have to talk to my husband. He’s Italian.”

“That’s a whole different league,” I say. “We can’t even begin to compete.” “I know,” she says. “Isn’t it incredible? I asked him once, why do you lie all the time? Always? Why do you feel the need to do that? And he told me, ‘Because then it feels like I’ve got away with something. It’s a kind of power’.” That is it, of course, in a nutshell. It is a struggle for power. If we choose to win by brute force, we go to jail. We cannot (some of us) allow ourselves to lose, but our partners frequently are relentless — they will never, ever surrender. Therefore we lie.

“You’re a man, you lie because you don’t want to get caught,” a male friend of mine says. This is my wife’s “coward” theory put plain. Questions such as why we have to avoid being “caught”, or who the “catcher” is, or, most pressing in the long run, how the hell she got appointed to that position, don’t need to be answered. The answer seems to be built structurally into our brains.

My friend is a writer. “You lie because you don’t want the lecture, the dirty look, the new entry in a catalogue of never forgotten betrayals” — he goes into an imitation-girlfriend voice — “ ‘This is just like when I needed you that time when I was using your car and it wouldn’t start and they were going to tow me and you were out at that bar with your friend . . . or whoever it was’.” My friend and I ourselves are in a bar for this conversation. He lights a cigarette, though technically speaking he’s “not smoking” right now.

He says: “Now you need a translation. ‘Your car’ means even though she had it, it was your problem, which is as it should be, and very satisfying too — because one of the underlying struggles that will last until the very final moments of the relationship and even slightly beyond is whether she ever actually ought to face a crisis alone.