A Scotsman was on a long train journey. He was already tired and just wanted to sleep. A rather lively lawyer sat across from him, and tried to strike up a conversation. The Scotsman brushed him off, saying that he had already travelled from Scotland, and was tired, just wanted to sleep.
The lawyer had an idea, his colleagues had said that the Scottish were a slow-witted people, and being a learned man, he thought he would have some fun.
"Would you like to play a game to pass the time?" the lawyer asked. The Scotsman declined. The Lawyer then said, "I will make it worth your while. For every question I ask you that you can't answer, you give me £5. You can then ask me a question, and if I do not know the answer, I will give you £500."
The Scotsman was intrigued, and agreed though he was still tired. The lawyer said, "Ok, I'll go first." He then asks a convoluted legal question, that the Scotsman couldn't possibly answer. The Scotsman just takes a £5 note from his wallet and gives it to the Lawyer. The lawyer was feeling a bit smug, and told the Scotsman to take his turn.
The Scotsman thinks for a moment, then asks the Lawyer, "What goes up a hill on 3 legs, and comes down it on 4?" The Lawyer is stumped. He calls all his learned friends on his cell phone, uses his laptop to search, while the Scotsman slept.
An hour later, the Lawyer wakes the Scotsman. "I don't know the answer to your question." The lawyer then gives the Scotsman £500. The Lawyer asks, "So, what does go up a hill on 3 legs, and comes down it on 4?"
The Scotsman hands the lawyer another £5 note and goes back to sleep.