Oakland Raiders punter Chris Kluwe believes that a lack of gay rights weakens societies.

The 31-year-old Kluwe is among the NFL's most outspoken supporters of gay rights. Last year, when he was with the Minnesota Vikings, Kluwe campaigned against passage of an unsuccessful amendment to the Minnesota Constitution which sought to define marriage as a heterosexual union. This year, he spoke out in support of Minnesota's gay marriage law, which takes effect on August 1.

In an interview with Bloomberg BusinessWeek to promote his upcoming book Beautifully Unique Sparkle Ponies, Kluwe said that his book explores the complexities of the human experience.

“[I]f you define someone by a single label, you miss out on so much of what makes them a person – whether that label be 'gay,' 'athlete,' 'nerd,' etc. Human beings are complex creatures, and to ignore that is laziness.”

“I would also like people to pay attention to the idea of rational empathy, and that as a society, we are walking down a path that's well-trodden throughout history. Every single human civilization has failed over time, and my belief is that it's due to lack of rational empathy, of understanding that if you don't have equality in your society, the conflicts you breed (whether internally or externally) will eventually cause its collapse,” Kluwe said.

Beautifully Unique Sparkle Ponies goes on sale Tuesday.