At a televised quiz show, the contestant who is standing on a platform is told to choose between two elevator doors facing him. One of the doors would lead to a wonderful prize, the other to an onerous task.<\/p>\n
In front of each elevator door was placed a uniformed sentinel, a person selected from the audience of the quiz show.<\/p>\n
One of the sentinels was required to only lie, and the person selected said he was a politician so this would not be much of a problem for him. The sentinels were informed of what the elevator doors led to.<\/p>\n
The other sentinel was required to only tell the truth, and as he was a mathematician this would not be a difficult problem for him, he said.<\/p>\n
The contestant was informed that one of the sentinels would certainly lie and the other would certainly tell the truth.<\/p>\n
The contestant was required to direct just one question to one of the sentinels for the purpose of selecting the elevator door with the prize.<\/p>\n
What was the winning question?<\/p>\n