GCD and son went fishing one summer day. While they were out in their boat, the boy suddenly became curious about the world around him. He asked his father, "Dad, how does this boat float?"
GCD replied, "Don't rightly know son."
A little later, the boy looked at his father and asked, "Dad, how do fish breath underwater?"
Once again the GCD replied, "Don't rightly know son."
A little later the boy asked his father, "Dad, why is the sky blue?"
Again, GCD replied, "Don't rightly know son."
Finally, the boy asked his father, "Dad, do you mind my asking you all of these questions?"
GCD replied, "Of course not, son. If you don't ask me questions, you'll never learn nothin'."