As their incomes rise, both men and women are more likely to have a higher sex drive, according to a study of almost 30,000 people from 170 countries. Only among men, however, does this translate into more frequent sex: male high earners have sex significantly more often than those on lower salaries, but income makes little or no difference for women.
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We hesitate to offer age-old insight into the phenomenon, realizing, of course, that this is an issue for science to straighten out at the cost of millions of dollars. But could the rich guys want more sex because they're more self-regarding? The primordial sin, pride, is self-serving. It wants things that serve the flesh, which money and sex do well. It makes sense that the guy who craves money also craves sex.