An old man was a witness in a burglary case.
The defense lawyer asked Sam, “Did you see my client commit this burglary?”
“Yes,” said Sam, “I saw him plainly take the goods.”
The lawyer asks Sam again, “Sam, this happened at night. Are you sure you saw my client commit this crime?”
“Yes, says Sam. “I saw him do it.”
Then the lawyer asks Sam, “Sam, listen, you are an 80-year-old, and your eyesight is probably bad. Just how far can you see at night?”
Sam says, “I can see the moon. How far is that?”