Absent-Minded Rider

A certain world renowned scientist was also recognized as a particularly absent-minded professor… One day, on board a train, he was unable to find his ticket. The conductor said, “Take it easy. You’ll find it.” When the conductor returned, the professor still couldn’t find the ticket. The conductor, recognizing the famous scientist, said, “I’m sure you bought a ticket. Just forget about it.”

“You’re very kind,” the professor said, “but I must find it, otherwise I won’t know where to get off.”