David Letterman on Wednesday ranted against gay marriage bans as he welcomed MSNBC's Rachel Maddow on his show.

“I think it has really crossed the line of being nonsense,” Letterman told Maddow, who is openly gay. “This ongoing, politically nuanced, religiously nuanced discussion of gay marriage, gay rights; it is absolute stupidity.”

“Humans have the right to do what humans do. That's it. End of story. There's no argument. There's no exceptions. Humans have rights and they get to do what humans get to do. Case closed. Good night.”

“It's beyond embarrassing, when you think about it now. Because it's exclusionary based on what?” Letterman rhetorically asked. “Well, nothing, really, other than the fear people have generated of who knows what.”

Maddow agreed and added that the issue is now dividing Republicans.

“I think it is becoming sort of a wedge issue for Republicans, and Democrats are essentially almost unanimously in support now,” said Maddow. (The video is embedded on this page. Visit our video library for more videos.)