Holmes and Watson

Sherlock Holmes and Doctor Watson are hiking. They hiked all day long and then, having gotten tired, went to sleep in their tent.

Holmes wakes up deep at night, wakes Watson and says, "Watson, do you see the bright stars and do you notice how clear the sky is? What can you deduce from it?"

"Well, this clearly tells us the weather tomorrow is going to be dry and sunny."

"No Watson, it's simplier than that. It just means that somebody has stolen our tent."