A detective in training is called to a room on his first day in, once there his instructor greets him and tells him he has a deck of fish cards. Alongside the instructor are two men who hold three cards from the same deck. He was given a paper reexplaining the prompt which had written on top: "Each man will say what he has, yet one man is lying... This man is the murderer." The first man began, he stated he held a shark, a shrimp, and a catfish. The second man stated he held two goldfish and a lion. Who is the murderer?
A common first answer is the second man, whereas a shrimp is not considered a fish in this case either... You can look over this again if you'd like now. The answer: The instructor There was only one liar, meaning if the deck was really of fish as the instructor said, they would both be lying in contrary to the prompt. Meaning the only way the statement could be true is if the instructor was the murderer.