Can we only ask practical questions at MSE?

You should only ask practical, answerable questions based on actual problems that you face. Chatty, open-ended questions diminish the usefulness of our site and push other questions off the front page.

It seems very strange to me that questions asked at MSE should always be practical. The questions that fits this guideline most (practical,answerable and actual) are homework problems. This guideline seems to apply more to SO. Isn't this help center giving users the wrong impression of what sort of questions we want at MSE ?

For example, one could interpret "based on actual problems you face" as that questions out of curiosity are not appreciated at MSE.

• I am retagging in the hopes that we can get this phrasing changed. – Willie Wong Jun 17 '13 at 8:26
• I think interpretation of 'practical' should be taken in context. – copper.hat Jun 24 '13 at 2:43

I interpret this in two ways:

Do not ask well-known open problems as questions.
It's not practical to ask MSE to prove the Riemann hypothesis for you. You're allowed to ask difficult, research level questions, but they shouldn't be attempts to "stump MSE" with famous conjectures. (Of course, if your question unexpectedly turns out to be equivalent to an open problem, that's okay, so long as it wasn't intentional.) You can, however, still ask things like "what methods of attack have been attempted to solve the Riemann hypothesis?"; this is what the tag is for.

Stay away from amorphous or non-factual questions.
With the exception of certain CW questions, such as book lists, all questions should be specific, clearly stated, and have a well-defined answer. Some wiggle room exists for "idea development" questions where the community helps the asker formulate a mathematical notion, e.g. "can one define distance between elements in finite fields?", but this is a grey area, and the question may still be closed if not written carefully enough.

There's still plenty of stuff to ask after following these rules. I see "actual problems you face" not as a request for solely homework problems, but for any question you come up with while studying mathematical material, whether it's a problem from your textbook, a step in a proof you don't understand, or a self-created problem for which you'd love to see a solution.

I interpret the word "practical" in this context as follows:

You should only ask questions which are practical to answer.

So for example, a question about why uniform convergence is an important property for sequences of continuous functions would be practical, whereas a question asking for a solution to the Riemann hypothesis would not.

Keep in mind that the "don't ask" page is network-wide, rather than specific to math.SE. I interpret the statements there as guidelines rather than rules, and I think that ultimately whether a question is acceptable is determined by the community.

• I think the problem that Kasper has concerns not what we think the content of that page means, but what new users (can) think. (Well, the small fraction of them that actually reads it before posting.) – Lord_Farin Jun 15 '13 at 21:11
• @Lord_Farin I don't think that's a very large concern, for the reason you cite. There's also little chance of changing the page since it is network-wide (although the FAQ pages are being changed around, so they might become site-specific--I'd have to look that up). – Alex Becker Jun 15 '13 at 21:31
• @Lord_Farin: At the very least our on-topic page is moderator editable, and we might want to consider making some improvements to it. Following this MSO thread, I am still uncertain whether we can have a site-specific dont-ask page. (We would need a community manager to make such a change, at any rate.) – user642796 Jun 16 '13 at 5:10

There is a very relevant discussion of this issue on MSO. This exact phrase was written for Stack Overflow before the rest of the SE network even existed; it doesn't work well if you take it literally on many sites. In the answers on the MSO question I linked are some efforts to translate the idea behind that to other types of sites. The most relevant ones for this site are probably the answers by Manishearth and myself, as they are written from our perspective as moderators of a scientific site.

From my answer on MSO:

I think that questions that are asked out of curiosity work fine on many sites. What distinguished the "good" kind from the "bad" kind is that the good questions are still focused on trying to gain a better understanding, and are not only based on idle curiosity.

• "not only based on idle curiosity." - hmm, not entirely sure about that; I can see somebody asking a good question after noticing some funny pattern coming up in something that was tried just for fun. – J. M. is a poor mathematician Jun 16 '13 at 7:28
• I like the answer given by Kaveh in that discussion: ask a question only if you care about knowing the answer. For example, picking up a book of interesting math problems and posting one problem after another just for the sake of upvotes is not a proper use of the site. – ˈjuː.zɚ79365 Jun 16 '13 at 7:38