A lot of users, like me, came to Puzzling.SE because we thought of it as a place that would become equivalent to PCG.SE, but for non-programming puzzles and that would coexist with a place to ask questions about puzzles rather than just for challenges.

Of course, our lack of clarity on what our standards are, along with a lack of a regular community to enforce those standards, is causing us to accumulate a glut of questions that most of us just sort of know are unsuitable for the site, but we can't seem to determine why except that they're low quality.

Recently, the issue has flared up on meta, and one of the answers pointed out that we still don't have a clear, unambiguous definition of what sorts of questions-as-challenges are on-topic.

While we've had closed-ended questions about whether specific types of puzzles are on-topic or not, I thought I'd create a unified space to decide on what types of puzzles are on-topic here.

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    $\begingroup$ I personally would love challenges. $\endgroup$
    – warspyking
    Commented Nov 18, 2014 at 19:51

3 Answers 3


Most of the ideas in this post have been shamelessly stolen from other Meta posts.

I suggest we emulate the behaviors of the following SE sites:

  1. Programmers
  2. StackOverflow
  3. CodeReview
  4. Code Golf

What I mean by this is we allow the same type of questions except in relation to puzzles rather than coding.

  1. Programmers: When you're at the whiteboard => Question about puzzles in general

    This isn't an exact mirror, but questions about puzzles should be on-topic. Here are a few questions that fit in this category:

    What are the criteria for determining the difficulty of Sudoku puzzle?

    In iterated Prisoner's Dilemma, how would a change in the payoff matrix affect strategy?

  2. Stack Overflow: When you're coding => When you need help solving a puzzle

    This is mainly for mass-producible puzzles but it could work for others as well. You must post the puzzle, what you have attempted so far, and what specific problem you are having. If you just post a crossword or sudoku puzzle and nothing else, then it should be downvoted, closed, and ultimately deleted.

    These types of questions will most likely get the most downvotes and close votes because just like on StackOverflow, many people won't follow the rules.

  3. Code Review => Help creating a puzzle

    You have created a puzzle. You wish to make sure that your puzzle doesn't have many possible answers because of some ambiguity or you want to make sure your puzzle isn't too easy or hard. Or perhaps you need advice on how to add one final clue to lead your users to an answer (or to throw them off). The key to this category is that we should avoid questions that are basically "please make me a puzzle".

  4. Code Golf => Fun and games

    This will probably be the bulk of the questions on this site. For this category, we need to have a strict set of rules.

    -No mass producible puzzles

    -It is the responsibility of the OP to provide enough context and information so that a single unambiguous solution can be found (or as few solutions as possible). A question that does not provide enough information (like this one) should be downvoted and closed.

    -All answers must provide explanations. If somebody posted a riddle, your answer better explain how each line fits your solution.

    -Each puzzle should be a self-contained post. All of the information required to solve the puzzle must be in the post. In other words, a reader should not have to re-read part 25 of your puzzle in another post. Multi-post (puzzles with a part 1, part 2, ..., part 30) puzzles should be discouraged or there should be a limit of perhaps 2-3 parts.

    -Probably more restrictions

Overall, this might make the scope of puzzling.se too broad, but I don't think it would.

  • $\begingroup$ This is way. This is exactly what I have wanted ti articulate $\endgroup$
    – d'alar'cop
    Commented Nov 20, 2014 at 0:38
  • $\begingroup$ I was actually thinking of producing a whole novel of interlinked puzzles (with about 50 or 60 parts) to post on this site over the span of a year or so. Then I decided against it. $\endgroup$
    – user88
    Commented Nov 20, 2014 at 1:07
  • $\begingroup$ @JoeZ. Oh wow, I just realized that I completely misread your question. This answer was meant to be for a question along the lines of "What should the scope of this site be?". I could have sworn I saw a topic like that somewhere here on Meta. $\endgroup$
    – jliv902
    Commented Nov 20, 2014 at 16:07
  • $\begingroup$ Well that's basically what we're talking about here, so it's alright, your question is still very suitable. $\endgroup$
    – user88
    Commented Nov 20, 2014 at 17:36
  • $\begingroup$ Item 3 is handled on PPCG by means of a sandbox question on the site Meta. That might be something to consider here; then puzzles could be vetted in the sandbox and still posted on the main site as instances of item 4. $\endgroup$
    – jscs
    Commented Nov 21, 2014 at 19:57

My suggestion:

On-topic: All types of puzzle except PPCG and chess.

  • Why should we exclude any type of puzzle except for the reason that there already exists a better place on SE to discuss it?

  • I don't buy the idea that some genres of puzzle are inherently superior to other genres. Sure, some are harder than others, but if we wanted to exclude easy puzzles then that's not specific to genre.


  • I agree with Joe that mass-produced puzzles should be out of scope. If one just copies a puzzle and keeps the same idea while changing a few details, that's dull.

  • But I don't agree that any particular genre of puzzle is particularly vulnerable to this (more than other genres). I'm pretty sure I can make a nearly-but-not-quite copy of a puzzle in any genre.

  • Excluding all language-based puzzles? Wow. Big step. That would really cut out everything except maths puzzles, which could just as well be on maths.SE. So then what would be the point of puzzling.SE?

One can of course deal with low-quality questions by just giving them a low score - downvoting them or refraining from upvoting them - instead of ruling them off-topic. Isn't that how the system is meant to work?

  • 3
    $\begingroup$ It's not so much whether certain genres of puzzles are superior, but more whether they're suitable to the Stack Exchange format or not. $\endgroup$
    – user88
    Commented Nov 17, 2014 at 21:00
  • $\begingroup$ @JoeZ, which genres are you thinking would be unsuitable for the format? $\endgroup$
    – A E
    Commented Nov 17, 2014 at 21:01
  • $\begingroup$ I'm writing up an answer as we speak. $\endgroup$
    – user88
    Commented Nov 17, 2014 at 21:02
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    $\begingroup$ @JoeZ, I reserve the right to change my mind if it's convincing. :) $\endgroup$
    – A E
    Commented Nov 17, 2014 at 21:09
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    $\begingroup$ As much as I don't believe that some puzzles are inherently superior, the empirical evidence shows some genres attracting much high quality that others, and I'd have no issue limiting to ones that seem to breed quality. $\endgroup$
    – xnor
    Commented Nov 17, 2014 at 21:13
  • $\begingroup$ @xnor what if that "quality" comes at the cost of users? I mean if the funnest (but "low" quality questions) are stricken... no one will come here and it will die. $\endgroup$
    – d'alar'cop
    Commented Nov 17, 2014 at 22:01
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    $\begingroup$ @d'alar'cop Yes, it's a tough balance. I think there's a happy medium somewhere that balances quality and users, but now we're far at the end of many users and low quality. $\endgroup$
    – xnor
    Commented Nov 17, 2014 at 22:04
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    $\begingroup$ @xnor I think this is the fundamental community debate. are we really experiencing low quality? how do we know that if we don't even know what we are? I agree many answers are a joke - but that's a non-fatal issue (especially for someone who has spent any time on SO!) $\endgroup$
    – d'alar'cop
    Commented Nov 17, 2014 at 22:05
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    $\begingroup$ I agree with you that you could take most puzzles and mass produce them just by changing a few details. You couldn't do that with a riddle though. But if he wants to eliminate both MPPs and riddles, there'd be nothing left! $\endgroup$ Commented Nov 18, 2014 at 3:30
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    $\begingroup$ @pacoverflow clearly limited. You don't see anything beyond MPPs and riddles? What about other puzzle genres that have smaller niches, but devout followings? $\endgroup$
    – yuritsuki
    Commented Nov 18, 2014 at 16:14
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    $\begingroup$ Just as a note: chess puzzles posted so far on this site are generally on topic. They have answers that are clearly recognizable as correct or incorrect and are interesting puzzles. Alot of riddle questions here are not so clear. Your questions are generally fine. Though clearly fit the custom close reason, i don't agree with that close reason being used for questions where a very small number of potential solutions are clearly superior. $\endgroup$
    – kaine
    Commented Nov 18, 2014 at 21:40

Here are my personal thoughts on the matter.

My vision of this Stack Exchange is, as I pointed out in the answer above, is a place where people can post interesting puzzles and get interesting answers for them, like PCG.SE but for regular puzzles.

To that end, here are some of the puzzle types that I would consider to be unsuitable for this site (and therefore believe should be declared off-topic):

Mass-producible puzzles

Mass-producible puzzles are puzzles of a specific type that can be produced in large quantities and have a small set of common shared strategies for solving.

I believe that these puzzles are unsuitable simply because there are too many of them, and if too many questions of a single type flood the site, as we saw with the party security questions, the site rapidly becomes uninteresting.

Riddles and language-based puzzles

Riddles, and other puzzles that depend on language (interpreting sentences of words and their phrasing in order to extract meaning from them), have too much inherent potential for ambiguity and inclarity.

This includes lateral thinking puzzles that depends on some quirk in the wording to arrive at the answer. However, it does not include puzzles that make use of just the letters in words in a specific way; I'm specifically talking about morphology and semantics.

This might lead one to believe that only puzzles with a mathematical abstraction are acceptable. I would say it's certainly a good rule of thumb, although a few exceptions might be made.

Of course, questions about the above puzzle types would still be on-topic.

I must emphasize that I'm not excluding the above puzzle types because they're somehow inherently worse. But even on PCG.SE, not all programming puzzles are suitable for Stack Exchange. I had my own experience with that trying to format a king-of-the-hill puzzle on PCG.SE; eventually there were just too many bugs with the format for the verification systems I had in place to be viable. While the question wasn't closed because of it, I would not try and do it again.

Some people believe that this site should strictly be a "Puzzle Theory" Q&A site, in which only such questions about puzzles are asked. If you believe this should be the case, then of course you would believe that none of these puzzles-as-challenges are on-topic, and the question is meaningless. However, I'd have to admit that my own activity would decrease dramatically on such a site, because it would no longer be what I see the site as being.

  • $\begingroup$ Let's talk in chat. $\endgroup$
    – xnor
    Commented Nov 17, 2014 at 21:17
  • $\begingroup$ I agree 100% with everything (as in the link you provided)... except about the "riddles and language-based puzzles". I think this is what this civil war is going to be about :p $\endgroup$
    – d'alar'cop
    Commented Nov 17, 2014 at 21:58
  • $\begingroup$ Interesting. I had too much to say for a comment so I've updated my answer. $\endgroup$
    – A E
    Commented Nov 17, 2014 at 23:05
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    $\begingroup$ Regarding "mass produced puzzles", a lot of puzzles can be considered a MPP if someone just copies it and changes a few details. Perhaps the only thing that can't be considered a MPP is a riddle. $\endgroup$ Commented Nov 18, 2014 at 3:28
  • 1
    $\begingroup$ Another person mentioned on a meta post that mass-producible puzzles must follow a common template. Making variations of a puzzle wouldn't necessarily count as creating a template, unless the variation was trivial enough so as to not really change the fundamental problem. $\endgroup$
    – user88
    Commented Nov 18, 2014 at 7:43
  • $\begingroup$ Yes. Perhaps 'template puzzles' would be a better term. Although even then they can still be original puzzles within a standard template which just provides the 'backstory'. $\endgroup$
    – A E
    Commented Nov 18, 2014 at 11:56
  • $\begingroup$ @JoeZ. I would find it helpful if you linked to some puzzles that you did not think are MPPs. $\endgroup$ Commented Nov 20, 2014 at 3:32
  • $\begingroup$ Here are a few. Here are a few more. $\endgroup$
    – user88
    Commented Nov 20, 2014 at 3:42
  • $\begingroup$ They're not all the best quality and a few of them are chestnuts, but they're all questions I wouldn't consider inherently mass-producible. $\endgroup$
    – user88
    Commented Nov 20, 2014 at 3:42

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