(Last updated: 14 July 1999.)
I've seen a few situation puzzles that are unsolvable because they're not really situation puzzles. In high school, for instance, a couple of friends of mine presented me with this situation:
A man walks into a laundromat, pulls an octopus from one of the washing machines, and leaves.
I asked them quite a few questions, as I recall, before discovering that they had made up the situation, had no answer in mind, and were answering "yes" or "no" at random.
There are also story games which appear to be situation puzzles but really aren't. Knowing the secret to these games means you can't be the guesser, so stop reading here (and have a friend read the rest of this page) if you want to try them out without knowing how they work.
Tammy R. Franklin provides a game called "What is Queen Anne?" It's presented as a situation puzzle, with the "situation" being "What is Queen Anne?" Guessers ask yes/no questions as usual. The trick is that the presenter has no answer in mind, merely determining each yes/no answer by the form of the question: when the question has an odd number of syllables (such as "Is Queen Anne a dog?"), the answer is always no, and when the question has an even number of syllables (such as "Is Queen Anne a pink dog?") then the answer is always yes (or vice versa, depending on the presenter's preference).
There's another game called "Psychiatrist" that operates similarly. The It (or Its, if you have more than one person in on the trick) tells the group: "I am an insane person; you are doctors trying to find out the nature of my insanity. To do so, ask me questions which can be answered by 'yes' or 'no'." It's a fun game for the It, though it can be kinda frustrating for the people guessing (and it takes an amazingly long time, usually, considering how simple the rule is).
Similar to those games is the yes/no story game, which goes like this:
Gather with a group of friends. Ask for a volunteer to try and guess a story, using only yes-or-no questions. When someone volunteers, have them leave the room so you and the others can "make up a story."
When the volunteer has left the room, you let everyone else in on the trick: if the volunteer's question ends in a vowel (a, e, i, o, u, or y, regardless of how it's pronounced) or the letter 's', the answer is "yes"; otherwise it's "no."
After a suitable interval you call the volunteer back into the room. They will probably be uncertain how to begin. Have them ask any old yes/no question (about the story) at all. They will be encouraged by the fact that everybody gives the same answer -- which seems to indicate that the group really did come up with a real story.
Questions proceed much as in the Queen Anne game. Eventually, the volunteer gives up, or everyone else can't keep a straight face any longer, or people get tired of it and decide to end it...
There are two problems with games of this type: