Mulla Nasruddin came from his village to the big city, and a rich friend invited him to his box at the opera.
Said the friend, “We will be sitting close to other people, so be sure to change your socks before you come!”
A short time after they entered their opera seats, the neighbors started turning their noses up at the bad smell.
“I told you to change your socks,” said the friend to Mulla.
“I most certainly did,” said Nasruddin. “And furthermore I knew you wouldn’t believe me, so I brought the old socks right here in my pocket to prove it!”