I'd always thought marrying a blood relative as close as a cousin was immoral, and certainly risky if you plan to have kids. Conventional wisdom says only primitive people who live in isolated places marry cousins. It leads to stupid children. But that's a myth.

It's the sort of myth that leads to stupid laws. Half the states in America have banned cousin marriage, but there's no good reason for it. You can marry your cousin and have perfectly intelligent kids.

Take Albert Einstein -- was he intelligent enough for you? His parents were cousins, and he married his cousin. So did Charles Darwin and Queen Victoria. Worldwide, 20 percent of all married couples are cousins.

A lot of "experts," politicians and clergymen, are dead set against cousin marriage, and they've convinced a lot of people, including many lawmakers, that marrying a cousin is a bad thing to do.

As with many of our laws, there is little reason for the ban. The laws date back hundreds of years to a time when the Catholic Church campaigned against cousin marriages, because in the Bible, in Leviticus, it says, "None of you shall approach to any that is near of kin."

But a cousin isn't terribly "near." Just ask Brian and Caren Wagner. Brian's dad and Caren's mom are brother and sister, so Brian and Caren spent a lot of time together at family functions. Eventually, they fell in love and decided to marry. This did not go over well with either of their parents.

"There was a phone call from my mother, to Brian's father, of, 'What are we gonna do about this?'" Caren told me. Continued...