How old do I think the earth is? You know what? I don't have any idea. I know it's pretty old, so it goes back a long, long way. I'm not sure anybody actually knows completely and absolutely how long, how old the earth is. I hear your mom was asking about evolution. You know, it's a theory that's out there. It's got some gaps in it, but in Texas we teach both creationism and evolution in our public schools, because I figured you're smart enough to figure out which one is right.
Drum, Kevin (18 August 2011), "Quote of the Day: How Old is the Earth?", Mother Jones