A young Law student, who had failed his Law exam, went up to the crusty old professor, who was renowned for having a razor sharp legal mind.
The student asked him, “Sir, do you really understand everything about this subject?”
The professor replied, “Actually, I probably do. Otherwise I wouldn’t be a professor, would I?”
The student, half expecting this response, then asked the professor, “Ok sir. So I’d like to ask you a question. If you can give me the correct answer, I will accept my marks as it is. If you can’t give me the correct answer, however, you’ll have to give me an A”.
The crusty old professor was a bit stumped by this, but since he believed that he knew everything, he replied, “Hmmmm, alright. So what’s the question?”
The student asked him, “What is legal but not logical, logical but not legal, and neither logical nor legal?”
The professor wracked his famous brain, but just could not come up with an answer. Finally he gave up and changed the student’s failing mark into an “A” as agreed. The student went away, very pleased with himself.
The professor continued to wrack his brain over the question all afternoon, but still could not get the answer.
So, finally, he called in a group of his brightest students and told them he had a really, really tough question for them to answer, “What is legal but not logical, logical but not legal, and neither logical nor legal?”
To the professor’s surprise (and embarrassment), all the students immediately raise their hands.
“All right”, the professor said and asked his favorite student to answer the question.
“It’s quite easy, sir” the student said. “You see, you are 75 years old and married to a 30 year old woman, which is legal, but not logical. Your wife has a 22 year old lover, which is logical, but not legal. And your wife’s lover failed his exam but you’ve just given him an A, which is neither legal, nor logical”.
The crusty old professor collapsed in his chair.
Image used under a Collective Commons License from https://commons.wikimedia.org/wiki/File:Anders_Sjoberg_(professor).jpg