I recall a joke in which a man taking public transport to work every day confuses the buses and gets on another one. It turns out that the bus is carrying patients of one of the institutions for people with mental disorders. When he realises the people he is among, he quickly heads towards the driver with a clear message: "Please let me out. I really am not crazy!" To which the driver, with angelic patience and a note of boredom in his voice, replies: "Sure, none of you are".