She just doesn't stop....

Ruth keeps surprising us with the things she says. Tonight we were driving home from my parents' house just minding our own business when she said this:

"I think that the Earth spins slowly because if it spinned faster the days and nights would be shorter."

Are 5 year-olds really supposed to be figuring stuff like that out on their own? We're not prepared to deal with her brain. Right now we are doing research about why exactly the days and nights are shorter in the winter time (something to do with the tilt of the Earth?) because she wants to know. I really should have applied myself more in my High School science class.