People who feel like they're stuck with a rule or restriction are more likely to be content with it than people who think that the rule isn't definite. The authors of a new study, which will be published in an upcoming issue of Psychological Science, a journal of the Association for Psychological Science, say this conclusion may help explain everything from unrequited love to the uprisings of the Arab Spring.

Psychological studies have found two contradictory results about how people respond to rules. Some research has found that, when there are new restrictions, you rationalize them; your brain comes up with a way to believe the restriction is a good idea. But other research has found that people react negatively against new restrictions, wanting the restricted thing more than ever.

Kristin Laurin of the University of Waterloo thought the difference might be absoluteness -- how much the restriction is set in stone. "If it's a restriction that I can't really do anything about, then there's really no point in hitting my head against the wall and trying to fight against it," she says. "I'm better off if I just give up. But if there's a chance I can beat it, then it makes sense for my brain to make me want the restricted thing even more, to motivate me to fight" Laurin wrote the new paper with Aaron Kay and Gavan Fitzsimons of Duke University.

In an experiment in the new study, participants read that lowering speed limits in cities would make people safer. Some read that government leaders had decided to reduce speed limits. Of those people, some were told that this legislation would definitely come into effect, and others read that it would probably happen, but that there was still a small chance government officials could vote it down.

People who thought the speed limit was definitely being lowered supported the change more than control subjects, but people who thought there was still a chance it wouldn't happen supported it less than these control subjects. Laurin says this confirms what she suspected about absoluteness; if a restriction is definite, people find a way to live with it.

This could help explain how uprisings spread across the Arab world earlier this year. When people were living under dictatorships with power that appeared to be absolute, Laurin says, they may have been comfortable with it. But once Tunisia's president fled, citizens of neighboring countries realized that their governments weren't as absolute as they seemed -- and they could have dropped whatever rationalizations they were using to make it possible to live under an authoritarian regime. Even more, the now non-absolute restriction their governments represented could have exacerbated their reaction, fueling their anger and motivating them to take action.

And how does this relate to unrequited love? It confirms people's intuitive sense that leading someone can just make them fall for you more deeply, Laurin says. "If this person is telling me no, but I perceive that as not totally absolute, if I still think I have a shot, that's just going to strengthen my desire and my feeling, that's going to make me think I need to fight to win the person over," she says. "If instead I believe no, I definitely don't have a shot with this person, then I might rationalize it and decide that I don't like them that much anyway."