What color is the sky?
*Blue.
Is it, really?
*Yes.
No it's not. The sky is purple.
*No, it's blue.
Why do you say it's blue?
*Because it is.
Because you say it is or because someone else says it is?
*Just because it is.
What color is the grass?
*Green.
Are you sure?
*Yes.
Nope -- it's pink.
*It isn't -- it's green.
Why?
*Because.
Because you know it's green or because you've been told it's green?
*Just because.
What color is dirt?
*Brown.
Positive?
*Yes.
Wrong again -- it's red.
*It's brown.
Because you know it is or because someone else thinks they know it is?
*Because...it just is.
So -- what color is the sky?
*I don't know.
Didn't you just say it was blue?
*I wouldn't argue with you if you said the sky was magenta.
The sky is purple.