A father and son went fishing one day. After a couple hours in the boat, the boy suddenly became curious about the world around him.

He asked his father, "How does this boat float?"

The father thought for a moment, then replied, "Don't rightly know, son."

The boy returned to his contemplation, then turned back to his father, "How do fish breathe underwater?"
Once again the father replied, "Don't rightly know, son."

A little later the boy asked his father, "Why is the sky blue?"

Again, the father replied. "Don't rightly know, son."

Worried he was going to annoy his father, he says, "Dad, do you mind my asking you all of these questions?"

"Of course not, son. If you don't ask questions, you'll never learn anything!"