Often, it's ordinary emotions - such as boredom, ambivalence or unhappiness - that drive infidelity, Schwartz said.
"Often, a lot of cheating happens when a relationship is going sideways or [when a couple is] in hiatus and never made a firm commitment in the first place," Schwartz said.
But while it's impossible to fully understand Weiner's motivations, the idea of a powerful (or once powerful) man cheating is far from new.
Historically, powerful men have had a so-called license to cheat, and a 2011 study in the journal Psychological Sciencefound that powerful men are more likely to cheat.
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"It's really been in the last 150 years that we have begun to hold men to a higher standard of fidelity" than in earlier times, Stephanie Coontz, a historian at The Evergreen State College in Washington and author of "Marriage, A History" (Viking Adult, 2005), previously told Live Science.
What's more, the archetypal politician's personality may make cheating more likely: They are energetic and driven, they have a need to be admired, and they meet lots of people, providing many opportunities for affairs, Schwartz said.
Throw in the throngs of starry-eyed women who are often 40 years younger than these men's wives, and it's not surprising many of them cheat, she said.
"They get way more opportunities than the average guy, which makes them feel like they're not screwing around too much if they're only doing it occasionally," Schwartz said.
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Even in nonfamous, happy couples, however, the decision about whether to cheat may come down to opportunity and consequences, Schwartz said. For their book, she and her co-authors conducted a survey to see how people would act if given a chance to cheat without any consequences.
"We asked if people would cheat if they knew it wouldn't affect the relationship, and the majority of people say they would," Schwartz said.
Even a sizable chunk of the couples who said they were very happy were open to straying, provided it didn't impact their relationship, she said.
Original article on Live Science.
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