Last-modified: 17 Aug 1993
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==> logic/situation.puzzles.s <== Jed's List of Situation Puzzles (with answers) "A man lies dead in a room with fifty-three bicycles in front of him. What happened?" This is a list of what I refer to (for lack of a better name) as situation puzzles. In the game of situation puzzles, a situation like the one above is presented to a group of players, who must then try to find out more about the situation by asking further questions. The person who initially presented the situation can only answer "yes" or "no" to questions (or occasionally "irrelevant" or "doesn't matter"). My list has been divided into two sections. Section 1 consists of situation puzzles which are set in a realistic world; the situations could all actually occur. Section 2 consists of puzzles which involve double meanings for one or more words and those which could not possibly take place in reality as we know it, plus a few miscellaneous others. See the end of the list for more notes and comments. This version of the list contains answers to the puzzles, as well as variants. Section 1: "Realistic" situation puzzles. 1.1. In the middle of the ocean is a yacht. Several corpses are floating in the water nearby. (SJ) 1.1. A bunch of people are on an ocean voyage in a yacht. One afternoon, they all decide to go swimming, so they put on swimsuits and dive off the side into the water. Unfortunately, they forget to set up a ladder on the side of the boat, so there's no way for them to climb back in, and they drown. 1.1a. Variant answer: The same situation, except that they set out a ladder which is just barely long enough. When they all dive into the water, the boat, without their weight, rises in the water until the ladder is just barely out of reach. (also from Steve Jacquot) 1.2. A man is lying dead in a room. There is a large pile of gold and jewels on the floor, a chandelier attached to the ceiling, and a large open window. (DVS; partial JM wording) 1.2. The room is the ballroom of an ocean liner which sank some time ago. The man ran out of air while diving in the wreck. 1.2a. Variant which puts this in section 2: same statement, ending with "a large window through which rays are coming." Answer: the rays are manta rays (this version tends to make people assume vampires are involved, unless they notice the awkwardness of the phrase involving rays). 1.3. A woman came home with a bag of groceries, got the mail, and walked into the house. On the way to the kitchen, she went through the living room and looked at her husband, who had blown his brains out. She then continued to the kitchen, put away the groceries, and made dinner. (partial JM wording) 1.3. The husband killed himself a while ago; it's his ashes in an urn on the mantelpiece that the wife looks at. It's debatable whether this belongs in section 2 for double meanings. 1.4. A body is discovered in a park in Chicago in the middle of summer. It has a fractured skull and many other broken bones, but the cause of death was hypothermia. (MI, from _Hill Street Blues_) 1.4. A poor peasant from somewhere in Europe wants desperately to get to the U.S. Not having money for airfare, he stows away in the landing gear compartment of a jet. He dies of hypothermia in mid-flight, and falls out when the landing gear compartment opens as the plane makes its final approach. 1.4a. Variant: A man is lying drowned in a dead forest. Answer: He's scuba diving when a firefighting plane lands nearby and fills its tanks with water, sucking him in with the water. He runs out of air while the plane is in flight; the plane then dumps its load of water, with him in it, onto a burning forest. (from Jim Moskowitz) 1.5. A man lives on the twelfth floor of an apartment building. Every morning he takes the elevator down to the lobby and leaves the building. In the evening, he gets into the elevator, and, if there is someone else in the elevator -- or if it was raining that day -- he goes back to his floor directly. However, if there is nobody else in the elevator and it hasn't rained, he goes to the 10th floor and walks up two flights of stairs to his room. (MH) 1.5. The man is a midget. He can't reach the upper elevator buttons, but he can ask people to push them for him. He can also push them with his umbrella. I've usually heard this stated with more details: "Every morning he wakes up, gets dressed, eats, goes to the elevator..." Ron Carter suggests a nice red herring: the man lives on the 13th floor of the building. 1.6. A woman has incontrovertible proof in court that her husband was murdered by her sister. The judge declares, "This is the strangest case I've ever seen. Though it's a cut-and-dried case, this woman cannot be punished." (This is different from #1.43.) (MH) 1.6. The sisters are Siamese twins. 1.6a. Variant: A man and his brother are in a bar drinking. They begin to argue (as always) and the brother won't get out of the man's face, shouting and cursing. The man, finally fed up, pulls out a pistol and blows his brother's brains out. He sits down to die. Answer: They are Siamese twins. In the original story, the argument started when one complained about the other's bad hygiene and bad breath. The shooter bled to death (from his brother's wounds) by the time the police arrived. (from Randy Whitaker, based on a 1987 _Weekly World News_ story) 1.7. A man walks into a bar and asks for a drink. The bartender pulls out a gun and points it at him. The man says, "Thank you," and walks out. (DVS) 1.7. The man has hiccups; the bartender scares them away by pulling a gun. 1.8. A man is returning from Switzerland by train. If he had been in a non-smoking car he would have died. (DVS; MC wording) 1.8. The man used to be blind; he's now returning from an eye operation which restored his sight. He's spent all his money on the operation, so when the train (which has no internal lighting) goes through a tunnel he at first thinks he's gone blind again and almost decides to kill himself. Fortunately, the light of the cigarettes people are smoking convinces him that he can still see. 1.8a. Variant: A man dies on a train he does not ordinarily catch. Answer: The man (a successful artist) has had an accident in which he injured his eyes. His head is bandaged and he has been warned not to remove the bandages under any circumstances lest the condition be irreversibly aggravated. He catches the train home from the hospital and cannot resist peeking. Seeing nothing at all (the same train-in-tunnel situation as above obtains, but without the glowing cigarettes this time), he assumes he is blinded and kills himself in grief. I like this version a lot, except that it makes much less sense that he'd be traveling alone. (from Bernd Wechner) 1.9. A man goes into a restaurant, orders abalone, eats one bite, and kills himself. (TM and JM wording) 1.9. The man was in a ship that was wrecked on a desert island. When there was no food left, another passenger brought what he said was abalone but was really part of the man's wife (who had died in the wreck). The man suspects something fishy, so when they finally return to civilization, he orders abalone, realizes that what he ate before was his wife, and kills himself. 1.9a. Variant: same problem statement but with albatross instead of abalone. Answer: In this version, the man was in a lifeboat, with his wife, who died. He hallucinated an albatross landing in the boat which he caught and killed and ate; he thought that his wife had been washed overboard. When he actually eats albatross, he discovers that he had actually eaten his wife. 1.9b. Variant answer to 1.9a, with a slightly different problem statement: the man already knew that he had been eating human flesh. He asks the waiter in the restaurant what kind of soup is available, and the waiter responds, "Albatross soup." Thinking that "albatross soup" means "human soup," and sickened by the thought of such a society (place in a foreign country if necessary), he kills himself. (from Mike Neergaard) 1.10. A man is found hanging in a locked room with a puddle of water under his feet. (This is different from #1.11.) 1.10. He stood on a block of ice to hang himself. The fact that there's no furniture in the room can be added to the statement, but if it's mentioned in conjunction with the puddle of water the answer tends to be guessed more easily. 1.11. A man is dead in a puddle of blood and water on the floor of a locked room. (This is different from #1.10.) 1.11. He stabbed himself with an icicle. 1.12. A man is lying, dead, face down in the desert wearing a backpack. (This is different from #1.13, #2.11, and #2.12.) 1.12. He jumped out of an airplane, but his parachute failed to open. Minor variant wording (from Joe Kincaid): he's on a mountain trail instead of in a desert. Minor variant wording (from Mike Reymond): he's got a ring in his hand (it came off of the ripcord). 1.12a. Silly variant: same problem statement, with the addition that one of the man's shoelaces is untied. Answer: He pulled his shoelace instead of the ripcord. 1.12b. Variant answer: The man was let loose in the desert with a pack full of poisoned food. He knows it's poisoned, and doesn't eat it -- he dies of hunger. (from Mike Neergaard) 1.13. A man is lying face down, dead, in the desert, with a match near his outstretched hand. (This is different from #1.12, #2.11, and #2.12.) (JH; partial JM wording) 1.13. He was with several others in a hot air balloon crossing the desert. The balloon was punctured and they began to lose altitude. They tossed all their non-essentials overboard, then their clothing and food, but were still going to crash in the middle of the desert. Finally, they drew matches to see who would jump over the side and save the others; this man lost. Minor variant wording: add that the man is nude. 1.14. A man is driving his car. He turns on the radio, listens for five minutes, turns around, goes home, and shoots his wife. (This is different from #1.15.) 1.14. The radio program is one of the call-up-somebody-and-ask-them-a- question contest shows; the announcer gives the phone number of the man's bedroom phone as the number he's calling, and a male voice answers. It's been suggested that such shows don't usually give the phone number being called; so instead the wife's name could be given as who's being called, and there could be appropriate background sounds when the other man answers the phone. 1.15. A man driving his car turns on the radio. He then pulls over to the side of the road and shoots himself. (This is different from #1.14.) 1.15. He worked as a DJ at a radio station. He decided to kill his wife, and so he put on a long record and quickly drove home and killed her, figuring he had a perfect alibi: he'd been at work. On the way back he turns on his show, only to discover that the record is skipping. 1.15a. Variant: The music stops and the man dies. Answer: The same, except it's a tape breaking instead of a record skipping. (from Michael Killianey) (See also #1.16, #1.19e, and #1.34a.) 1.16. Music stops and a woman dies. (DVS) 1.16. The woman is a tightrope walker in a circus. Her act consists of walking the rope blindfolded, accompanied by music, without a net. The musician (organist, or calliopist, or pianist, or whatever) is supposed to stop playing when she reaches the end of the rope, telling her that it's safe to step off onto the platform. For unknown reasons (but with murderous intent), he stops the music early, and she steps off the rope to her death. 1.16a. Variant answer: The woman is a character in an opera, who "dies" at the end of her song. 1.16b. Variant answer: The "woman" is the dancing figure atop a music box, who "dies" when the box runs down. (Both of the above variants would probably require placing this puzzle in section 2 of the list.) 1.16c. Variant: Charlie died when the music stopped. Answer: Charlie was an insect sitting on a chair; the music playing was for the game Musical Chairs. (from Bob Philhower) (See also #1.15a, #1.19e, and #1.34a.) 1.17. A man is dead in a room with a small pile of pieces of wood and sawdust in one corner. (from "Coroner's Inquest," by Marc Connelly) 1.17. The man is a blind midget, the shortest one in the circus. Another midget, jealous because he's not as short, has been sawing small pieces off of the first one's cane every night, so that every day he thinks he's taller. Since his only income is from being a circus midget, he decides to kill himself when he gets too tall. 1.17a. Slightly variant answer: Instead of sawing pieces off of the midget's cane, someone has sawed the legs off of his bed. He wakes up, stands up, and thinks he's grown during the night. 1.17b. Variant: A pile of sawdust, no net, a man dies. Answer: A midget is jealous of the clown who walks on stilts. He saws partway through the stilts; the clown walks along and falls and dies when they break. (from Peter R. Olpe) 1.18. A flash of light, a man dies. (ST original) 1.18. The man is a lion-tamer, posing for a photo with his lions. The lions react badly to the flash of the camera, and the man can't see properly, so he gets mauled. 1.18a. Variant: He couldn't find a chair, so he died. Answer: He was a lion-tamer. This one is kind of silly, but I like it, and it sounds possible to me (though I'm told a whip is more important than a chair to a lion-tamer). (from "Reaper Man," with Karl Heuer wording) 1.19. A rope breaks. A bell rings. A man dies. (KH) 1.19. A blind man enjoys walking near a cliff, and uses the sound of a buoy to gauge his distance from the edge. One day the buoy's anchor rope breaks, allowing the buoy to drift away from the shore, and the man walks over the edge of the cliff. 1.19a. Variant: A bell rings. A man dies. A bell rings. Answer: A blind swimmer sets an alarm clock to tell him when and what direction to go to shore. The first bell is a buoy, which he mistakenly swims to, getting tired and drowning. Then the alarm clock goes off. In other variations, the first bell is a ship's bell, and/or the second bell is a hand-bell rung by a friend on shore at a pre-arranged time. 1.19b. Variant answer to 1.19a: The man falls off a belltower, pulling the bell-cord (perhaps he was climbing a steeple while hanging onto the rope), and dies. The second bell is one rung at his funeral. Could also be a variant on 1.19 (as suggested by Mike Neergaard): the bell-cord breaks when he falls (and there's no second bell involved). 1.19c. Variant answer to 1.19a: The man is a boxer. The first bell signals the start of a round; the second is either the end of the round or a funeral bell after he dies during the match. Could also be a variant on 1.19 (as suggested by Mike Neergaard): a boxing match in which the top rope breaks, tumbling a boxer to the floor (and he dies of a concussion). 1.19d. Variant: The wind stopped blowing and the man died. Answer: The sole survivor of a shipwreck reached a desert isle. Unfortunately, he was blind. Luckily, there was a freshwater spring on the island, and he rigged the ship's bell (which had drifted to the island also) at the spring's location. The bell rang in the wind, directing him to water. When he was becalmed for a week, he could not find water again, and so he died of thirst. (from Peter R. Olpe) 1.19e. Variant: The music stopped and the man died. Answer: Same as 1.19a, but the blind swimmer kept a portable transistor radio on the beach instead of a bell. When the batteries gave out, he got lost and drowned. (from Joe Kincaid) (See also #1.15a, #1.16, and #1.34a.) 1.20. A woman buys a new pair of shoes, goes to work, and dies. (DM) 1.20. The woman is the assistant to a (circus or sideshow) knife-thrower. The new shoes have higher heels than she normally wears, so that the thrower misjudges his aim and one of his knives kills her during the show. 1.20a. Variant: A woman sees her husband entering a certain place of business and insists on dissolving their partnership. Answer: The husband is a knife-thrower; the woman is his assistant as well as his wife. She sees him going into an optometrist's office and decides that if he's having trouble with his eyes she doesn't want him throwing knives at her. (from _How Come -- Again?_) 1.21. A man is riding a subway. He meets a one-armed man, who pulls out a gun and shoots him. (SJ) 1.21. Several men were shipwrecked together. They agreed to survive by eating each other a piece at a time. Each of them in turn gave up an arm, but before they got to the last man, they were rescued. They all demanded that the last man live up to his end of the deal. Instead, he killed a bum and sent the bum's arm to the others in a box to "prove" that he had fulfilled the bargain. Later, one of them sees him on the subway, holding onto an overhead ring with the arm he supposedly cut off; the other realizes that the last man cheated, and kills him. 1.21a. Variant wording: A man sends a package to someone in Europe and gets a note back saying "Thank you. I received it." Answer: This is just a simpler version; the shipwreck situation is the same, and the man actually did send his own arm. 1.21b. Variant wording: Two men throw a box off of a cliff. Answer: Exactly the same situation as in 1.21a (one slight variation has a hand in the box instead of a whole arm), with the two men being two of the fellow passengers who had already lost their arms. 1.21c. Variant wording: A man in a Sherlock Holmes-style cape walks into a room, places a box on the table and leaves. Answer: In this one he's wearing the cape either to disguise the fact that he hasn't really cut off his arm/hand as required, or else simply in order to hide his now-missing limb. (from Joe Kincaid) 1.22. Two women are talking. One goes into the bathroom, comes out five minutes later, and kills the other. 1.22. Both women are white; the one whose house this takes place in is single. A black friend of the other woman, the one who goes into the bathroom, was recently killed, reportedly by the KKK. The woman who goes into the bathroom discovers a bloodstained KKK robe in the other's laundry hamper, picks up a nail file from the medicine cabinet (or some other impromptu weapon), and goes out and kills the other. 1.22a. Variant: A man goes to hang his coat and realizes he will die that day. Answer: The man (who is black) has car trouble and is in need of a telephone. He asks at the nearest house and on being invited in goes to hang his coat, whereupon he notices the white robes of the Ku Klux Klan in the closet. (from Bernd Wechner) 1.23. A man is sitting in bed. He makes a phone call, saying nothing, and then goes to sleep. (SJ) 1.23. He is in a hotel, and is unable to sleep because the man in the adjacent room is snoring. He calls the room next door (from his own room number he can easily figure out his neighbor's, and from the room number, the telephone number). The snorer wakes up, answers the phone. The first man hangs up without saying anything and goes to sleep before the snorer gets back to sleep and starts snoring again. 1.23a. Slightly variant answer: It's a next-door neighbor in an apartment building who's snoring, rather than in a hotel. The caller thus knows his neighbor and the phone number. 1.24. A man kills his wife, then goes inside his house and kills himself. (DH original, from "Nightmare in Yellow," by Fredric Brown) 1.24. It's the man's fiftieth birthday, and in celebration of this he plans to kill his wife, then take the money he's embezzled and move on to a new life in another state. His wife takes him out to dinner; afterward, on their front step, he kills her. He opens the door, dragging her body in with him, and all the lights suddenly turn on and a group of his friends shout "Surprise!" He kills himself. (Note that the whole first part, including the motive, isn't really necessary; it was just part of the original story.) 1.25. Abel walks out of the ocean. Cain asks him who he is, and Abel answers. Cain kills Abel. (MWD original) 1.25. Abel is a prince of the island nation that he landed on. A cruel and warlike prince, he waged many land and naval battles along with his father the king. In one naval encounter, their ship sank, the king died, and the prince swam to a deserted island where he spent several months building a raft or small boat. In the meantime, a regent was appointed to the island nation, and he brought peace and prosperity. When Prince Abel returned to his kingdom, Cain (a native fisherman) realized that the peace of the land would only be maintained if Abel did not reascend to his throne, and killed the prince (with a piece of driftwood or some other impromptu weapon). 1.26. Two men enter a bar. They both order identical drinks. One lives; the other dies. (CR; partial JM wording) 1.26. The drinks contain poisoned ice cubes; one man drinks slowly, giving them time to melt, while the other drinks quickly and thus doesn't get much of the poison. The fact that they drink at different speeds could be added to the statement, possibly along with red herrings such as saying that one of the men is big and burly and the other short and thin. 1.27. Joe leaves his house, wearing a mask and carrying an empty sack. An hour later he returns. The sack is now full. He goes into a room and turns out the lights. (AL) 1.27. Joe is a kid who goes trick-or-treating for Halloween. 1.28. A man takes a two-week cruise to Mexico from the U.S. Shortly after he gets back, he takes a three-day cruise which doesn't stop at any other ports. He stays in his cabin all the time on both cruises. As a result, he makes $250,000. (MI, from "The Wager") 1.28. He's a smuggler. On the first cruise, someone brings the contraband to his cabin, and he hides it in an air conditioning duct. Returning to the U.S., he leaves without the contraband, and so passes through customs with no trouble. On the second trip, he has the same cabin on the same ship. Because it doesn't stop anywhere, he doesn't have to go through customs when he returns, so he gets the contraband off safely. 1.29. Hans and Fritz are German spies during World War II. They try to enter America, posing as returning tourists. Hans is immediately arrested. (JM) 1.29. Hans and Fritz do everything right up until they're filling out a personal-information form and have to write down their birthdays. Fritz' birthday is, say, July 7, so he writes down 7/7/15. Hans, however, was born on, say, June 20, so he writes down 20/6/18 instead of what an American would write, 6/20/18. Note that this is only a problem because they *claim* to be returning Americans; as has been pointed out to me, there are lots of other nations which use the same date ordering. 1.30. Tim and Greg were talking. Tim said "The terror of flight." Greg said "The gloom of the grave." Greg was arrested. (MPW original, from "No Refuge Could Save," by Isaac Asimov) 1.30. Another WWII story. Greg is a German spy. His "friend" Tim is suspicious, so he plays a word-association game with him. When Tim says "The land of the free," Greg responds with "The home of the brave." Then Tim says "The terror of flight," and Greg says "The gloom of the grave." Any U.S. citizen knows the first verse of the national anthem, but only a spy would have memorized the third verse. (Why Tim knew the third verse is left as an exercise to the reader.) 1.31. A man is found dead in his parked car. Tire tracks lead up to the car and away. (SD) 1.31. The dead man was the driver in a hit-and-run accident which paralyzed its victim. The victim did manage to get the license plate number of the car; now in a wheelchair, he eventually tracked down the driver and shot and killed him. 1.32. A man dies in his own home. (ME original) 1.32. His home is a houseboat and he has run out of water while on an extended cruise. 1.32a. Variant wording: A man dies of thirst in his own home. This version goes more quickly because it gives more information; but it may be less likely to annoy people who think the original statement is too vague. 1.33. A woman in France in 1959 is waiting in her room, with all the doors locked from the inside, for her husband to come home. When he arrives, the house has burned to the ground and she's dead. (JM, from _How Come -- Again?_) 1.33. This is apparently a true story. The hot sun reflected from the woman's large mirror (which I speculate may have been imperfectly flat and therefore focused the sunlight, but I don't know for sure) and heated the lingerie she was wearing to the burning point. She was absorbed in a book at the time and didn't notice the heat until her clothing was afire. Nobody could get to her to help because her doors were locked from the inside. Please disregard the version of this answer from previous editions of this list; it's not true. 1.34. A man gets onto an elevator. When the elevator stops, he knows his wife is dead. (LA; partial KH wording) 1.34. He's leaving a hospital after visiting his wife, who's on heavy life-support. When the power goes out, he knows she can't live without the life-support systems (he assumes that if the emergency backup generator were working, the elevator wouldn't lose power; this aspect isn't entirely satisfactory, so in a variant, the scene is at home rather than in a hospital). 1.34a. Variant: The music stops and a woman dies. Answer: The woman is confined in an iron lung, and the music is playing on her radio or stereo. The power goes out. (from Randy Whitaker) (See also #1.15a, #1.16, and #1.19e.) 1.35. Three men die. On the pavement are pieces of ice and broken glass. (JJ) 1.35. A large man comes home to the penthouse apartment he shares with his beautiful young wife, taking the elevator up from the ground floor. He sees signs of lovemaking in the bedroom, and assumes that his wife is having an affair; her beau has presumably escaped down the stairs. The husband looks out the French windows and sees a good-looking man just leaving the main entrance of the building. The husband pushes the refrigerator out through the window onto the young man below. The husband dies of a heart attack from overexertion; the young man below dies from having a refrigerator fall on him; and the wife's boyfriend, who was hiding inside the refrigerator, also dies from the fall. 1.36. She lost her job when she invited them to dinner. (DS original) 1.36. Let's say "she" is named Suzy, and "they" are named Harry and Jane. Harry is an elderly archaeologist who has found a very old skeleton, which he's dubbed "Jane" (a la "Lucy"). Suzy is a buyer for a museum; she's supposed to make some sort of purchase from Harry, so she invites him to have a business dinner with her (at a restaurant). When she calls to invite him, he keeps talking about "Jane," so Suzy assumes that Jane is his wife and says to bring her along. Harry, offended, calls Suzy's boss and complains; since Suzy should've known who Jane was, she gets fired. 1.37. A man is running along a corridor with a piece of paper in his hand. The lights flicker and the man drops to his knees and cries out, "Oh no!" (MP) 1.37. The man is delivering a pardon, and the flicker of the lights indicates that the person to be pardoned has just been electrocuted. 1.38. A car without a driver moves; a man dies. (EMS) 1.38. The murderer sets the car on a slope above the hot dog stand where the victim works. He then wedges an ice block in the car to keep the brake pedal down, and puts the car in neutral, after which he flies to another city to avoid suspicion. It's a warm day; when the ice melts, the car rolls down the hill and strikes the hot dog man at his roadside stand, killing him. 1.39. As I drive to work on my motorcycle, there is one corner which I go around at a certain speed whether it's rainy or sunny. If it's cloudy but not raining, however, I usually go faster. (SW original) 1.39. There's a car wash on that corner. On rainy days, the rain reduces traction. On sunny days, water from the car wash has the same effect. If rain is threatening, though, the car wash gets little business and thus doesn't make the road wet, so I can take the corner faster. 1.40. A woman throws something out a window and dies. (JM) 1.40. The object she throws is a boomerang. It flies out, loops around, and comes back and hits her in the head, killing her. Boomerangs do not often return so close to the point from which they were thrown, but I believe it's possible for this to happen. 1.40a. Silly variant answer: She's in a submarine or spacecraft and throws a heavy object at the window, which breaks. 1.41. An avid birdwatcher sees an unexpected bird. Soon he's dead. (RSB original) 1.41. He is a passenger in an airplane and sees the bird get sucked into an engine at 20,000 feet. 1.42. There are a carrot, a pile of pebbles, and a pipe lying together in the middle of a field. (PRO; partial JM wording) 1.42. They're the remains of a melted snowman. 1.43. Two brothers are involved in a murder. Though it's clear that one of them actually committed the crime, neither can be punished. (This is different from #1.6.) (from "Unreasonable Doubt," by Stanley Ellin) 1.43. One of the brothers (A) confesses to the murder. At his trial, his brother (B) is called as the only defense witness; B immediately confesses, in graphic detail, to having committed the crime. The defense lawyer refuses to have the trial stopped, and A is acquitted under the "reasonable doubt" clause. Immediately afterward, B goes on trial for the murder; A is called as the only defense witness and HE confesses. B is declared innocent; and though everyone knows that ONE of them did it, how can they tell who? Further, neither can be convicted of perjury until it's decided which of them did it... I don't know if that would actually work under the US legal system, but someone else who heard the story said that his father was on the jury for a VERY similar case in New York some years ago. Mark Brader points out that the brothers might be convicted of conspiracy to commit perjury or to obstruct justice, or something of that kind. 1.44. An ordinary American citizen, with no passport, visits over thirty foreign countries in one day. He is welcomed in each country, and leaves each one of his own accord. (PRO) 1.44. He is a mail courier who delivers packages to the different foreign embassies in the United States. The land of an embassy belongs to the country of the embassy, not to the United States. 1.45. If he'd turned on the light, he'd have lived. (JM) 1.45. A man was shot during a robbery in his store one night. He staggered into the back room, where the telephone was, and called home, dialing by feel since he hadn't turned on the light. Once the call went through he gasped, "I'm at the store. I've been shot. Help!" or words to that effect. He set the phone down to await help, but none came; he'd treated the telephone pushbuttons like cash register numbers, when the arrangements of the numbers are upside down reflections of each other. The stranger he'd dialed had no way to know where "the store" was. 1.46. A man is found dead on the floor in the living room. (ME original) 1.46. The dead man was playing Santa Claus, for whatever reason; he slipped while coming down the chimney and broke his neck. 1.46a. Variant answer: The dead man WAS Santa Claus. This moves the puzzle to section 2 as far as I'm concerned. 1.47. A man is found dead outside a large building with a hole in him. (JM, modified from PRO) 1.47. The man was struck by an object thrown from the roof of the Empire State Building. Originally I had the object being a penny, but several people suggested that a penny probably wouldn't be enough to penetrate someone's skull. Something aerodynamic and heavier, like a dart, was suggested, but I don't know how much mass would be required. 1.47a. Variant: A man is found dead outside a large marble building with three holes in him. Answer: The man was a paleontologist working with the Archaeological Research Institute. He was reviving a triceratops frozen in the ice age when it came to life and killed him. This couldn't possibly happen because triceratops didn't exist during the ice age. (from Peter R. Olpe) 1.48. A man is found dead in an alley lying in a red pool with two sticks crossed near his head. (PRO) 1.48. The man died from eating a poisoned popsicle. 1.49. A man lies dead next to a feather. (PRO) 1.49. The man was a sword swallower in a carnival side-show. While he was practicing, someone tickled his throat with the feather, causing him to gag. 1.50. There is blood on the ceiling of my bedroom. (MI original) 1.50. A mosquito bit me, and I swatted it when it later landed on my ceiling (so the blood is my own as well as the mosquito's). 1.51. A man wakes up one night to get some water. He turns off the light and goes back to bed. The next morning he looks out the window, screams, and kills himself. (CR; KK wording) 1.51. The man is a lighthouse keeper. He turns off the light in the lighthouse and during the night a ship crashes on the rocks. Seeing this the next morning, the man realizes what he's done and commits suicide. 1.51a. Variant, similar to #1.15: The light goes out and a man dies. Answer: The lighthouse keeper uses his job as an alibi while he's elsewhere committing a crime, but the light goes out and a ship crashes, thereby disproving the alibi. The lighthouse keeper kills himself when he realizes his alibi is no good. (From Eric Wang) 1.51b. Variant answer to 1.51a: Someone else's alibi is disproven. (A man commits a heinous crime, claiming as his alibi that he was onboard a certain ship. When he learns that it was wrecked without reaching port safely, he realizes that his alibi is disproven and commits suicide to avoid being sent to prison.) (From Eric Wang) 1.52. She grabbed his ring, pulled on it, and dropped it. (JM, from _Math for Girls_) 1.52. They were skydiving. He broke his arm as he jumped from the plane by hitting it on the plane door; he couldn't reach his ripcord with his other arm. She pulled the ripcord for him. 1.52a. Sketch of variant answer: The ring was attached to the pin of a grenade that he was holding. Develop a situation from there. 1.53. A man sitting on a park bench reads a newspaper article headlined "Death at Sea" and knows a murder has been committed. 1.53. The man is a travel agent. He had sold someone two tickets for an ocean voyage, one round-trip and one one-way. The last name of the man who bought the tickets is the same as the last name of the woman who "fell" overboard and drowned on the same voyage, which is the subject of the article he's reading. 1.54. A man tries the new cologne his wife gave him for his birthday. He goes out to get some food, and is killed. (RW original) 1.54. The man is a beekeeper, and the bees attack en masse because they don't recognize his fragrance. Randy adds that this is based on something that actually happened to his grandfather, a beekeeper who was severely attacked by his bees when he used a new aftershave for the first time in 10 or 20 years. 1.55. A man in uniform stands on the beach of a tropical island. He takes out a cigarette, lights it, and begins smoking. He takes out a letter and begins reading it. The cigarette burns down between his fingers, but he doesn't throw it away. He cries. (RW) 1.55. He is a guard / attendant in a leper colony. The letter (to him) tells him that he has contracted the disease. The key is the cigarette burning down between his fingers -- leprosy is fairly unique in killing off sensory nerves without destroying motor ability. 1.56. A man went into a restaurant, had a large meal, and paid nothing for it. (JM original) 1.56. The man was a famous artist. A woman who collected autographs saw him dining; after he left the restaurant, she purchased the check that he used to pay for the meal from the restaurant manager. The check was therefore never cashed, so the artist never paid for the meal. 1.57. A married couple goes to a movie. During the movie the husband strangles the wife. He is able to get her body home without attracting attention. (from _Beyond the Easy Answer_) 1.57. The movie is at a drive-in theatre. 1.58. A man ran into a fire, and lived. A man stayed where there was no fire, and died. (Eric Wang original) 1.58. The two men were working in a small room protected by a carbon dioxide gas fire extinguisher system, when a fire broke out in an adjoining room. One of the men ran through the fire and escaped with only minor burns. The other one stayed in the room until the fire extinguishers kicked in, and died of oxygen starvation. (This originally involved a halon gas extinguisher, but those don't work that way; fortunately, Gisle Hannemyr pointed out that CO2 extinguishers do work that way. Gisle says a CO2 extinguisher on a Norwegian ship a few years ago did go off accidentally when there was no fire, killing everyone in the engine room.) 1.59. A writer with an audience of millions insisted that he was never to be interrupted while writing. After the day when he actually was interrupted, he never wrote again. (JM, from _How Come?_) 1.59. He was a skywriter whose plane crashed into another plane. 1.60. Beulah died in the Appalachians, while Craig died at sea. Everyone was much happier with Craig's death. (JM, from _How Come?_) 1.60. Beulah and Craig were hurricanes. 1.61. Mr. Browning is glad the car ran out of gas. (JM, from _Home Come?_) 1.61. Mr. and Mrs. Browning had just gotten married. Mrs. Browing was subject to fits of depression. They had their first fight soon after they were married; Mr. Browning stormed out of the house, and Mrs. Browning went into the garage and started up the car, intending to kill herself by filling the garage with car exhaust. But the car ran out of gas quickly, and Mr. Browning, returning home to apologize, found Mrs. Browning in time to summon help and restore her to health. 1.62. A man is sitting suspended over two pressurized containers. Suddenly, he dies. (NK original) 1.62. He's riding a bicycle or motorcycle, and he crashes and dies. 1.63. A man leaves a motel room, goes to his car, and honks the horn. (AS original) 1.63. It's the middle of the night. The man goes outside to get something from his car, but as the parking lot is set apart from the building, he forgets which room he was in. His wife is deaf, so he honks the car horn loudly, waking up everyone else in the motel. The other residents all get up and turn on their room lights; the man then returns to the one dark room. 1.64. Two dead people sit in their cars on a street. (AG) 1.64. Because there was a heavy fog, two people driving in opposite directions on the same road both stuck their heads out of their windows to better see the road's center line. Their heads hit each other at high speed, killing them both. Andreas says this is based on an actual accident. 1.65. A woman lies dead in the street near a car. (AG) 1.65. She was on a motorcycle, and her long hair got caught on the car's antenna. It ripped out part of her scalp and she bled to death. Andreas says this is also based on an actual accident. 1.66. A riverboat filled with passengers suddenly capsized, drowning most of those aboard. (from _How Come -- Again?_) 1.66. The boat was moving along a river in India when a large snake dropped onto the deck. The passengers all rushed to the other side of the boat, thereby overturning it. This is apparently based on a true incident reported in the _World Almanac_. Section 2: Double meanings, fictional settings, and miscellaneous others. 2.1. A man shoots himself, and dies. (HL) (This is different from #2.2.) 2.1. The man is a heroin addict, and has contracted AIDS by using an infected needle. In despair, he shoots himself up with an overdose, thereby committing suicide. 2.2. A man walks into a room, shoots, and kills himself. (HL) (This is different from #2.1.) 2.2. The man walks into a casino and goes to the craps table. He bets all the money he owns, and shoots craps. Since he is now broke, he becomes despondent and commits suicide. 2.3. Adults are holding children, waiting their turn. The children are handed (one at a time, usually) to a man, who holds them while a woman shoots them. If the child is crying, the man tries to stop the crying before the child is shot. (ML) 2.3. Kids getting their pictures taken with Santa. I see #2.1, #2.2, and #2.3 as different enough from each other to merit separate numbers, although they all rely on the same basic gimmick of alternate meanings of the word "shoot." 2.4. Hiking in the mountains, you walk past a large field and camp a few miles farther on, at a stream. It snows in the night, and the next day you find a cabin in the field with two dead bodies inside. (KL; KD and partial JM wording) 2.4. It's the cabin of an airplane that crashed there because of the snowstorm. 2.4a. Variant wording: A cabin, on the side of a mountain, locked from the inside, is opened, and 30 people are found dead inside. They had plenty of food and water. (from Ron Carter) 2.5. A man marries twenty women in his village but isn't charged with polygamy. 2.5. He's a priest; he is marrying them to other people, not to himself. 2.6. A man is alone on an island with no food and no water, yet he does not fear for his life. (MN) 2.6. The "island" is a traffic island. 2.7. Joe wants to go home, but he can't go home because the man in the mask is waiting for him. (AL wording) 2.7. A baseball game is going on. The base-runner sees the catcher waiting at home plate with the ball, and so decides to stay at third base to avoid being tagged out. 2.7a. Variant: Two men are in a field. One is wearing a mask. The other man is running towards him to avoid him. Answer: the same, but the catcher isn't right at home plate; the runner is trying to get home before the catcher can. (from Hal Lowery, by way of Chris Riley) This phrasing would allow the puzzle to migrate to section 1, but I don't like it as much. 2.8. A man is doing his job when his suit tears. Fifteen minutes later, he's dead. (RM) 2.8. The man is an astronaut out on a space walk. 2.9. A dead man lies near a pile of bricks and a beetle on top of a book. (MN) 2.9. The man was an amateur mechanic, the book is a Volkswagen service manual, the beetle is a car, and the pile of bricks is what the car fell off of. 2.10. At the bottom of the sea there lies a ship worth millions of dollars that will never be recovered. (TF original) 2.10. The Eagle landed in the Sea of Tranquility and will likely remain there for the foreseeable future. 2.11. A man is found dead in the arctic with a pack on his back. (This is different from #1.12, #1.13, and #2.12.) (PRO) 2.11. It's a wolf pack; they've killed and eaten (most of) the man. 2.12. There is a dead man lying in the desert next to a rock. (This is different from #1.12, #1.13, and #2.11.) (GH) 2.12. The dead man is Superman; the rock is Green Kryptonite. Invent a reasonable scenario from there. 2.13. As a man jumps out of a window, he hears the telephone ring and regrets having jumped. (from "Some Days are Like That," by Bruce J. Balfour; partial JM wording) 2.13. This is a post-holocaust scenario of some kind; for whatever reason, the man believes himself to be the last human on earth. He doesn't want to live by himself, so he jumps, just before the telephone rings... (of course, it could be a computer calling, but he has no way of knowing). 2.14. Two people are playing cards. One looks around and realizes he's going to die. (JM original) 2.14. The one who looks around sees his own reflection in the window (it's dark outside), but not his companion's. Thus, he realizes the other is a vampire, and that he's going to be killed by him. 2.15. A man lies dead in a room with fifty-three bicycles in front of him. 2.15. The "bicycles" are Bicycle playing cards; the man was cheating at cards, and when the extra card was found, he was killed by the other players. 2.15a. Variant: There are 53 bees instead of 53 bicycles. Answer: The same (Bee is another brand of playing cards). 2.15b. Variant: There are 51 instead of 53. Answer: Someone saw the guy conceal a card, and proved the deck was defective by turning it up and pointing out the missing ace. Or, the game was bridge, and the others noticed the cheating when the deal didn't come out even. The man had palmed an ace during the shuffle and meant to put it in his own hand during the deal, but muffed it. (both answers from Mark Brader) 2.16. A horse jumps over a tower and lands on a man, who disappears. (ES original) 2.16. A chess game; knight takes pawn. 2.16a. Variant: It's the year 860 A.D., at Camelot. Two priests are sitting in the castle's chapel. The queen attacks the king. The two priests rise, shake hands, and leave the room. Answer: The two priests are playing chess; one of them just mated by moving his queen. (from Ellen M. Sentovich) 2.16b. Variant: A black leader dies in Africa. Answer: The black leader is a chess king, and the game was played in Africa. (from Erick Brethenoux) 2.17. A train pulls into a station, but none of the waiting passengers move. (MN) 2.17. It's a model train set. 2.17a. Variant: The Orient Express is derailed and a kitten plays nearby. Answer: The Orient Express is a model train which has been left running unattended. The kitten has playfully derailed it. (from Bernd Wechner) 2.18. A man pushes a car up to a hotel and tells the owner he's bankrupt. (DVS; partial AL and JM wording) 2.18. It's a game of Monopoly. 2.18a. Variant: The car came out of the blue and the man came into some money. Answer: The same; in this case the car token passes Go and the player collects $200. (from "Mo," whose full name I missed) 2.19. Three large people try to crowd under one small umbrella, but nobody gets wet. (CC) 2.19. The sun is shining; there's no rain. 2.20. A black man dressed all in black, wearing a black mask, stands at a crossroads in a totally black-painted town. All of the streetlights in town are broken. There is no moon. A black-painted car without headlights drives straight toward him, but turns in time and doesn't hit him. (AL and RM wording) 2.20. It's daytime; the sun is out. 2.21. Bob and Carol and Ted and Alice all live in the same house. Bob and Carol go out to a movie, and when they return, Alice is lying dead on the floor in a puddle of water and glass. It is obvious that Ted killed her but Ted is not prosecuted or severely punished. 2.21. Alice is a goldfish; Ted is a cat. 2.21a. A very common variant uses the names Romeo and Juliet instead, to further mislead audiences. For example: Romeo is looking down on Juliet's dead body, which is on the floor surrounded by water and broken glass. (from Adam Carlson) 2.21b. Minor variant: Tom and Jean lay dead in a puddle of water with broken pieces of glass and a baseball nearby. Answer: Tom and Jean are both fish; it was a baseball, rather than a cat, that broke their tank. (from Mike Reymond) 2.22. A man rides into town on Friday. He stays one night and leaves on Friday. (KK) 2.22. Friday is a horse. 2.22a. Variant with the same basic gimmick: A woman comes home, sees Spaghetti on the wall and kills her husband. Answer: Spaghetti was the name of her pet dog. Her husband had it stuffed and mounted after it made a mess on his rug. (Simon Travaglia original) 2.23. Bruce wins the race, but he gets no trophy. (EMS) 2.23. Bruce is a horse. 2.24. A woman opens an envelope and dyes. (AL) 2.24. Should be done orally; the envelope is an envelope of dye, and she's dying some cloth, but it sounds like "opens an envelope and dies" if said out loud. 2.25. A man was brought before a tribal chief, who asked him a question. If he had known the answer, he probably would have died. He didn't, and lived. (MWD original) 2.25. The native chief asked him, "What is the third baseman's name in the Abbot and Costello routine 'Who's on First'?" The man, who had no idea, said "I don't know," the correct answer. However, he was a major smartass, so if he had known the answer he would have pointed out that What was the SECOND baseman's name. The chief, being quite humorless, would have executed him on the spot. This is fairly silly, but I like it too much to remove it from the list. 2.26. Two men are found dead outside of an igloo. (SK original) 2.26. The men have gone spelunking and have taken an Igloo cooler with them so they can have a picnic down in the caves. They cleverly used dry ice to keep their beer cold, not realizing that as the dry ice sublimed (went from solid state to vapor state) it would push the lighter oxygen out of the cave and they would suffocate. 2.27. A man is born in 1972 and dies in 1952 at the age of 25. (DM) 2.27. He's born in room number 1972 of a hospital and dies in room number 1952. The numbers can of course vary; it was originally set up with those numbers reversed (born in 1952, died in 1972), but I like it better this way. Attributions key: When I know who first told me the current version of a puzzle, I've put initials in parentheses after the puzzle statement; this is the key to those acknowledgments. The word "original" following an attribution means that, to the best of my knowledge, the cited person invented that puzzle. If a given puzzle isn't marked "original" but is attributed, that just means that's the first person I heard it from. I would appreciate it if attributions for originals were not removed; however, this list is hereby entered into the public domain, so do with it what you wish. LA == Laura Almasy RSB == Ranjit S. Bhatnagar CC == Chris Cole MC == Matt Crawford MWD == Matthew William Daly KD == Ken Duisenberg SD == Sylvia Dutcher ME == Marguerite Eisenstein TF == Thomas Freeman AG == Andreas Gammel JH == Joaquin Hartman MH == Marcy Hartman KH == Karl Heuer GH == Geoff Hopcraft DH == David Huddleston MI == Mark Isaak SJ == Steve Jacquot JJ == J|rgen Jensen KK == Karen Karp NK == Nev King SK == Shelby Kilmer KL == Ken Largman AL == Andy Latto HL == Howard Lazoff ML == Merlyn LeRoy DM == Dan Murray RM == "Reaper Man" (real name unknown) TM == Ted McCabe JM == Jim Moskowitz DM == Damian Mulvena MN == Jan Mark Noworolski PRO == Peter R. Olpe (from his list) MP == Martin Pitwood CR == Charles Renert EMS == Ellen M. Sentovich (from her list) AS == Annie Senghas ES == Eric Stephan DS == Diana Stiefbold ST == Simon Travaglia DVS == David Van Stone RW == Randy Whitaker MPW == Matthew P Wiener SW == Steve Wilson (not sure of name) Special thanks to Jim Moskowitz, Karl Heuer, and Mark Brader, for a lot of discussion of small but important details and wording. Notes and comments: My outtakes list (items removed from this list for various reasons, most of which came down to the fact that I didn't like them) is now available from the rec.puzzles archive server. There are many possible wordings for most of the puzzles in this list. Most of them have what I consider the best wording of the variants I've heard; if you think there's a better way of putting one or more of them, or if you don't like my categorization of any of them, or if you have any other comments or suggestions, please drop me a note. If you know others not on this list, please send them to me. Of course, in telling a group of players one of these situations, you can add or remove details, either to make getting the answer harder or easier, or simply to throw in red herrings. I've made a few specific suggestions along these lines in the answer list, available in a separate file. Also in the answer list are variant problem statements and variant answers. Bibliography: The game of situation puzzles is also known by a variety of other names: mystery questions, story riddles, lateral thinking puzzles, mini-mysteries, minute mysteries, missing links, how come?, situational puzzles, law school puzzles, quistels (in the Netherlands and other parts of Europe), mystery puzzles, and so on. I prefer the term 'situation puzzles,' but I change my mind every few years when a new term that I like more comes along. At any rate, here are some sources for these puzzles, under a variety of names. Unfortunately, almost all of these books are out of print and extremely difficult to find. Try inter-library loan, and be prepared to wait. I don't know of any such books outside of the US (though at least the Sloane book is also printed in Canada, Europe, and Australia), but I'd be happy to include references to such in future editions if anyone sends me bibliographical info. On this edition of my list, I have included a few puzzles from these books which I didn't previously have. I've paraphrased them and cited the sources, which I hope should be good enough to avoid copyright infringement; however, I hope to contact the various copyright holders soon and get explicit permission to include more of their puzzles. If I fail to get that permission, a few of the items on this list may go away in the next edition. _Games_ magazine (bibliographical data currently unavailable). They ran a situation-puzzle contest recently, but I have yet to see any of the results. _Math for Girls_ (bibliographical data unavailable). Rogers, Agnes, _How Come?_ (1953: Doubleday & Company, Inc., New York). Library of Congress catalog number 53-5756. OCLC #1612919. The author may also be listed as Agnes Rogers Allen. With its sequel (see below), the classic volume on the subject; is probably the original source for quite a few standard situation puzzles, though Rogers says she does not know who invented the form. Nor does she know the source of most of those she includes -- like all good folklore, situation puzzles are difficult to trace to their origins. Unfortunately, both these books are long out of print. Besides their historical value, these two come furnished with delightful illustrations of various wrong approaches to some of the puzzles. These versions were definitely intended to be read from the book, though; the puzzle statements are much more long-winded than the versions in my list. Rogers, Agnes, and Sheehan, Richard G., _How Come -- Again?_ (1960: Doubleday & Company, Inc., New York). Library of Congress catalog number 60-13745. OCLC #2580602. Sloane, Paul, _Lateral Thinking Puzzlers_ (1992: Sterling Publishing Co., Inc., 387 Park Avenue South, New York, 10016). ISBN 0-8069-8227-6. There's a lot of overlap here with the rec.puzzles archives, including a lot of puzzles that I wouldn't even consider doing as situation puzzles (such as the infamous "12 balls" problem). Still, it does have one or two nice situation puzzles in it. Warning: these are not lateral thinking puzzles in the sense in which I like to use that phrase -- each puzzle has a definite correct answer, and creativity and sideways leaps of logic aren't rewarded unless they result in that answer. Cover price $US 4.95; should be available (or orderable) in most chain bookstores in the US. _Stories With Holes_ (bibliographical data unavailable). Weintraub, Richard, and Krieger, Richard, _Beyond the Easy Answer: exploring new perspectives through creative problem-solving games_ (1979: Zenger Publications, Inc., Gateway Station 802, Culver City, CA 90230). ISBN 0-934508-00-3. Contains a variety of puzzles and games, most of which aren't really situation puzzles (and many of which are in the rec.puzzles archives), plus some creativity games. Out of print. History of List: original compilation 11/28/87 major revision 08/09/89 further additions 08/23/89 - 10/21/90 variants added to answer list 07/04/90 editing and renumbering 07/25/90 - 11/11/90 items removed; title changed 09/20/90 - 11/11/90 editing and additions 02/26/92 - 09/17/92 more additions (incl. biblio.) 03/31/93 - 05/03/93 --Jed Hartman firstname.lastname@example.org (as of 5/93) ==> logic/smullyan/black.hat.p <== Three logicians, A, B, and C, are wearing hats, which they know are either black or white but not all white. A can see the hats of B and C; B can see the hats of A and C; C is blind. Each is asked in turn if they know the color of their own hat. The answers are: A: "No." B: "No." C: "Yes." What color is C's hat and how does she know? ==> logic/smullyan/black.hat.s <== A must see at least one black hat, or she would know that her hat is black since they are not all white. B also must see at least one black hat, and further, that hat had to be on C, otherwise she would know that her hat was black (since she knows A saw at least one black hat). So C knows that her hat is black, without even seeing the others' hats. ==> logic/smullyan/fork.three.men.p <== Three men stand at a fork in the road. One fork leads to Someplaceorother; the other fork leads to Nowheresville. One of these people always answers the truth to any yes/no question which is asked of him. The other always lies when asked any yes/no question. The third person randomly lies and tells the truth. Each man is known to the others, but not to you. What is the least number of yes/no questions you can ask of these men and pick the road to Someplaceorother? Does the answer change if the third man randomly answers? ==> logic/smullyan/fork.three.men.s <== One question, and you only need one man of any type: "If I were to ask you whether the left fork leads to Someplaceorother, and you chose to answer that question with the same degree of truth as you answer this question, would you then answer 'yes'?" The truthteller will say "yes" if the left fork leads to Someplaceorother, and "no" otherwise. The liar will answer the same, since he will lie about where the left fork leads, and he will lie about lying. The randomizer may either lie or tell the truth about this one question, but either way he is behaving like either the truthteller or the liar and thus must correctly report the road to Someplaceorother. If however the third person randomly answers yes or no it is clear that you must ask at least two questions, since you might be asking the first one of the randomizer and there is nothing you can tell from his answers. Start by asking A "Is B more likely to tell the truth than C?" If he answers "yes", then: If A is truthteller, B is randomizer, C is liar. If A is liar, B is randomizer, C is truthteller. If A is randomizer, C is truthteller or liar. If he answers "no", then: If A is truthteller, B is liar, C is randomizer. If A is liar, B is truthteller, C is randomizer. If A is randomizer, B is truthteller or liar. In either case, we now know somebody (C or B, respectively) who is either a truthteller or liar. Now, use the technique for finding information from a truthteller/liar, viz., you ask him the following question: "If I were to ask you if the left fork leads to Someplaceorother, would you say 'yes'?" If the answer is "yes", take the left fork, if "no" take the right fork. ==> logic/smullyan/fork.two.men.p <== Two men stand at a fork in the road. One fork leads to Someplaceorother; the other fork leads to Nowheresville. One of these people always answers the truth to any yes/no question which is asked of him. The other always lies when asked any yes/no question. By asking one yes/no question, can you determine the road to Someplaceorother? ==> logic/smullyan/fork.two.men.s <== The fact that there are two is a red herring - you only need one of either type. You ask him the following question: "If I were to ask you if the left fork leads to Someplaceorother, would you say 'yes'?" If the person asked is a truthteller, he will answer "yes" if the left fork leads to Someplaceorother, and "no" otherwise. But so will the liar. So, either way, go left is the answer is "yes", and right otherwise. It is possible, of course, that the liars are malicious, and they will tell the truth if they figure out that you are trying to trick them. ==> logic/smullyan/integers.p <== Two logicians place cards on their foreheads so that what is written on the card is visible only to the other logician. Consecutive positive integers have been written on the cards. The following conversation ensues: A: "I don't know my number." B: "I don't know my number." A: "I don't know my number." B: "I don't know my number." ... n statements of ignorance later ... A or B: "I know my number." What is on the card and how does the logician know it? ==> logic/smullyan/integers.s <== If A saw 1, she would know that she had 2, and would say so. Therefore, A did not see 1. A says "I don't know my number." If B saw 2, she would know that she had 3, since she knows that A did not see 1, so B did not see 1 or 2. B says "I don't know my number." If A saw 3, she would know that she had 4, since she knows that B did not see 1 or 2, so A did not see 1, 2 or 3. A says "I don't know my number." If B saw 4, she would know that she had 5, since she knows that A did not see 1, 2 or 3, so B did not see 1, 2, 3 or 4. B says "I don't know my number." ... n statements of ignorance later ... If X saw n, she would know that she had n + 1, since she knows that ~X did not see 1 ... n - 1, so X did see n. X says "I know my number." And the number in n + 1. ==> logic/smullyan/painted.heads.p <== While three logicians were sleeping under a tree, a malicious child painted their heads red. Upon waking, each logician spies the child's handiwork as it applied to the heads of the other two. Naturally they start laughing. Suddenly one falls silent. Why? ==> logic/smullyan/painted.heads.s <== The one who fell silent, presumably the quickest of the three, reasoned that his head must be painted also. The argument goes as follows. Let's call the quick one Q, and the other two D and S. Let's assume Q's head is untouched. Then D is laughing because S's head is painted, and vice versa. But eventually, D and S will realize that their head must be painted, because the other is laughing. So they will quit laughing as soon as they realize this. So, Q waits what he thinks is a reasonable amount of time for them to figure this out, and when they don't stop laughing, his worst fears are confirmed. He concludes that his assumption is invalid and he must be crowned in crimson too.