He looked up from his easy chair and asked, "What made you do that"?
She looked at him and said, "50 years of lousy sex"!
He sat there contemplating his wifes actions and got up and walked over to her and smacked the hell out of her.
She looked up and said to him, "I supposed thats in retaliation for me hitting you, right"?
He said, "Nope, it's because you knew the damned difference"!

