# “Copying” someone else's comment for an answer

This is similar but different to this question. I am often reading through current questions and, as I am trying to think of an answer see a helpful hint in the comments.

Is it unethical to base an answer on someone else's comment?

There are a couple of cases to consider here: sometimes a short comment might be as short as "use MVT," and that is enough to trigger the rest of the answer for me. In this case, my intuition says that the answer is "mostly" my own work. I would probably post as myself and begin with "as ____ said above, we can use the MVT... ." In this case, it can even be difficult to know if I thought of the idea first or got it from the comments.

Other times someone posts an idea but isn't sure how to finish. If I see where they are going and can finish the answer for them, who gets credit?

In the most extreme case, someone basically posts a full answer as a comment, in which case the consensus seems to be to post as community if you want to answer.

What are peoples' thoughts on this? I suppose these might just require context. On the one hand, we can err on the side of not taking undue credit and just post as community. On the other, if it feels like you come up with "most" of the answer, should you just take the credit?

Note: to distinguish from the linked question, I am not referring to the case where an old question has no answers but a partial answer in the comments.

• There might be a reason why someone posts a hint as a comment instead of posting a full answer, namely, to encourage OP to get the answer and to post it as an answer herself. If you step in and post a complete answer, it's not so much a question of taking undue credit, as of depriving the questioner of the experience of working out the answer on her own, from the hint. – Gerry Myerson Mar 21 '16 at 5:39
• By the way, if someone wants to base an answer on my earlier comment, I will not consider it unethical. – Gerry Myerson Mar 21 '16 at 22:15
• I have received criticism (almost always from the original asker) before for posting relatively strong hints and sketches as answers. I know most answerers understand that we aren't supposed to be doing anyones homework, but there have been askers who have frustrated me with the other outlook. If I have the suspicion that a poster is not going to appreciate my answer, I would rather just post it as a comment and have it be less likely for them to engage me further. – PVAL-inactive Mar 21 '16 at 23:25
• @PVAL, opinions differ as to whether posting a question that is homework-like is beneficial, but the principle that users should be free to answer as they wish was never considered any less important than the ability of voters to hit the up/down/close/reopen/delete buttons in whatever way they like. In particular, there has never been the idea that "we aren't supposed to answer homework questions", and users who harrass others for posting answers are engaging in abuse. – zyx Mar 22 '16 at 1:18
• @zyx Sorry I think you misunderstood me. I meant when I merely gave a hint instead of doing someones work I have been pestered by someone (usually the asker) into writing down a complete proof and "doing their homework for them". My comment about the answerers just meant while I think most active contributers (say commenting on meta) will understand my views in this, I don't trust that the average question asker will always (especially if the question itself shows significant misunderstanding of the material and even the question being asked). – PVAL-inactive Mar 22 '16 at 2:00
• I was really just trying to explain my reasons to post something which many (including myself) would construe as an answer as a comment. – PVAL-inactive Mar 22 '16 at 2:02
• It sounds like you meant "answerers understand that we aren't obligated" to do homework (or anything else), which is certainly true, as is your observation about OPs. In the posted wording it seemed that the assertion was "we are supposed [to not]" answer particular questions and my response was to that. Your reasons for posting comments are perfectly understandable. My view is that a question "gets what it gets" and that even the most meager reply is fine, by definition. @PVAL – zyx Mar 22 '16 at 2:39
• I hate it when I post a hint in a comment, and someone posts an answer based on that hint before the OP even has a chance to react... if you figure out the solution to a question after reading a hint, enjoy it. And in particular, give the OP the chance to figure out the problem himself and feel the same enjoyment. – roman Mar 23 '16 at 13:22
• I wouldn't mind anybody basing their answers on my comments either, long as it's either a verbatim quote or a substantial expansion of it. Botching or misinterpreting my comment is a different can of worms, however. – J. M. isn't a mathematician Mar 25 '16 at 1:42
• Yes, maybe "only hint wanted" question modes or styles could be a thing. "Please give me a map, but I would like to search for the treasure on my own." – mathreadler Mar 27 '16 at 20:34

Comment-answers are not answers. The system doesn't treat them as answers, no reputation gain is possible, it is not possible for others to upvote [edit: whoops, you can upvote a comment; but it's not quite the same], downvote, correct, edit, or otherwise directly engage with a comment.

If a user posts a complete answer as a comment, then that user has mis-used a comment. It is much more common for a user to post an incomplete answer as a comment. Then it is not bad for someone else to come along, flesh out the content and write a complete answer.

Sometimes, users believe in hinting or helping the OP along, and view this as an educational opportunity for the OP. There is short-term value in not expanding these comments into answers assuming the OP is willing to engage with the commenter. But these questions and answers have very little long-term value. Indeed, one of the common failings of online fora is for someone to search and find incomplete threads.

Whether you choose to shortcut the hinters is ultimately up to you. In the overall StackExchange mentality, it is in fact definitely encouraged for you to provide good, complete answers whenever possible. But the Math.SE culture is a bit different, and worth thinking about.

I sometimes expand comments into answers. But I rarely do it on any question that was recently asked. One annoying thing is that unanswered questions are routinely brought back to the front page automatically by the system, in order that they might receive an answer. This is not good when the question is already answered! This fills the front page with somewhat uninteresting content and kicks other, more relevant questions, off the front page.

If I see a question that has been brought back to the front page, but has an answer in a comment, I provide an answer whenever I am capable.

• "it is not possible for others to upvote [...] a comment" Are you sure about that? :-) – quid Mar 23 '16 at 22:18
• You're right! You can definitely upvote comments. I suppose I consider the culture around comment upvoting so totally different than question and answer upvoting that it doesn't come immediately to mind. But the sentiment remains the same. – davidlowryduda Mar 24 '16 at 15:43
• The point was of course tangential. That said, I do not feel that the culture around comment upvoting is much different. – quid Mar 24 '16 at 20:03
• I agree with this except for some of the value words. I would have said "one of the common features of online fora is for someone to search and find incomplete threads"; I do not regard that as a failure. Long-term value need outweigh the short term benefit. – Lee Mosher Mar 27 '16 at 14:14

Comments are adequately credited by words like "as stated in the comments by user $U$ ... ". The CW mode has its disadvantages, and not everyone will want to use it.

It makes sense for authors to decide their use of CW based on whether they want to give more users the ability to edit the answer. CW has beneficial applications such as answers that require regular updates.

Avoiding reputation gains through CW is an ineffective form of posturing (it suggests at the same time that one does care about reputation on non-CW posts). It would be better to limit use of CW to intended use cases such as compiled lists, where giving more users edit capability has a good chance to improve an answer.

• What are the disadvantages of CW mode? – joriki Mar 22 '16 at 16:26
• More users able to make unwanted edits on the answer, and more users feeling "invited" to alter the answer. After some edit wars on CW answers I had posted, I stopped using CW. @joriki – zyx Mar 22 '16 at 16:31
• I've posted plenty of CW answers to lift comments into answers and don't remember ever encountering such problems. – joriki Mar 22 '16 at 17:03
• I still disagree with the "posturing" part of your answer. Not wanting to appear as if one might be trying to gain from the work of others is not necessarily posturing. (I also don't see how it suggests that one does care about reputation on non-CW posts, since caring about looking like a free-rider is different from caring about reputations points. (Not that I disapprove of caring about reputations points.)) – joriki Mar 22 '16 at 17:05
• Visibly disassociating one's behavior from some other alternative (and there are only two alternatives here, CW and non-CW) is an assertion of moral superiority relative to the people who choose the alternative, or will be read as that by a large fraction of the audience. The point of doing it visibly is the assumption that many in the audience consider the alternative behavior to be negative. Having the gesture be visible constitutes an acceptance and promotion of the negative interpretation, so the moral posturing becomes part of it whether or not the author intends to posture. @jori – zyx Mar 22 '16 at 20:12
• That's my opinion, anyway, and it would not be uninteresting to have a side discussion of "posturing". The point I consider more important is that use of CW should not be described as something required or as superior to the alternative. It is an option for the user to choose. @joriki – zyx Mar 22 '16 at 20:17
• The part about "opposed rather than accommodated" referred to this comment of yours: "Having the gesture be visible constitutes an acceptance and promotion of the negative interpretation, so the moral posturing becomes part of it whether or not the author intends to posture." I interpreted that to mean that one shouldn't accept the negative interpretation, but oppose it. – joriki Mar 22 '16 at 22:11
• "The point I consider more important is that use of CW should not be described as something required or as superior to the alternative" Is this symmetric? That is does it hold for use replaced by non-use? If so, how is this compatible with you passing judgments on it in OP? – quid Mar 22 '16 at 22:12
• That alleged symmetry is between very different things. The people who may interpret non-CW answers as an attempt to grab reputation points aren't taking part in this discussion. For the purposes of this discussion, their attitudes are an empirical fact. Your interpretation as moral posturing, by contrast, is your interpretation, that you could change right now if you wanted to. No-one here is accusing you of trying to grab reputation points, but you're accusing me of posturing. There's no symmetry there. – joriki Mar 22 '16 at 22:51
• I did respond to that: "I also don't see how it suggests that one does care about reputation on non-CW posts, since caring about looking like a free-rider is different from caring about reputations points." If you found empirically that it strongly correlates, it may well be that some people are posturing. But the remark in the answer isn't phrased as an empirical finding; it makes a statement about what it is in general, which in its generality necessarily also applies to me. You say I "accuse" you of judging me -- would you not consider calling my behaviour "moral posturing" a judgement? – joriki Mar 22 '16 at 23:27
• It does not only point out the opinion exists, rather it documents it by voicing the opinion quite vehemently. That's a difference. "[...]is an assertion of moral superiority relative to the people who choose the alternative[...]" Maybe they just want to allow more users to edit? It could make sense in this situation since such answers are often still terse. – quid Mar 22 '16 at 23:43
• The point is not the wording but that you repeat your point multiple times. To "point out the opinion exists" the first paragraph would have been sufficient. On the sentence, my point is that the behavior your criticize is compatible with the use-case you promote. It is not quite clear which actual practical problem you want to solve. – quid Mar 23 '16 at 0:22
• Your penultimate sentence seems unrelated to what I wrote. I was asking you what practical problem related to the (non-)use of CW you want to solve. You seem to blow up a problem for the sake of complaining about it. As far as I am concerned, It is pretty irrelevant if CW is used or not, and I doubt most users even routinely check the status of posts. I guess I just do not understand you concern about this pretty trivial matter. – quid Mar 23 '16 at 1:06
• From your reaction I get the impression you in fact understood by now the inherently contradictory nature of your contribution to this thread. I will not continue the side-show. – quid Mar 23 '16 at 11:21
• No, I don't prefer that other wording; it also includes "posturing" and in addition "charade". I'd bet against high odds that a survey would find that most people take "posturing" to have pejorative associations. If you didn't intend any pejorative associations, you could simply replace it, if only because it has pejorative associations for me. I'm not sure which of the many definitions at dictionary.com you mean; one of them is "an affected or unnatural attitude". – joriki Mar 23 '16 at 12:21

I deleted my earlier answer because it was unduly judgemental and not thought through properly. After a long exchange of comments under zyx's answer, I do want to provide an alternative answer again now because I still disagree with zyx's answer.

It appears that there are different attitudes to using CW for lifting comments into answers. Good reasons have been offered both for and against this practice, and no-one who does or doesn't follow it should be accused of trying to gain points off the work of others or of moral posturing.

My personal opinion, based on my personal experience, remains that the downside of CW posts being easier to edit is not very relevant in this case, as this has never happened to any of the comments I've lifted using CW, and that using CW is preferable to make sure that no-one gets the impression that reputation is being unduly collected. That doesn't imply that someone who prefers not to use CW is in fact unduly collecting reputation.

• I stated a very clear position that "the principle that users should be free to answer as they wish was never considered any less important than the ability [to vote freely] .... users who harrass others for posting answers are engaging in abuse", and other variations on that theme in my answer, in the comments below it, and in numerous previous threads on this meta. – zyx Mar 25 '16 at 1:28
• Given that this goes beyond the position in your first two paragraphs, I don't know what disagreement you consider this answer to be expressing. You appear to be saying that posting an opinion on meta about a general practice in the abstract, is equivalent to individualized harrassment that might inspire fear in answer-posters. I believe that the number of CW answers that have been criticized as "posturing" (or something akin to that) on the main site is approximately 0.0000, and I do not see much potential for my answer to inspire more cases. What then, is this answer contesting? – zyx Mar 25 '16 at 1:48
• On the other hand, the fear of "giving the wrong impression" by posting non-CW is very real, as demonstrated by your answers and comments in this thread. So while the principle of freedom to post is symmetrical between CW and non-CW, fear of posting only exists in connection with one of those two options, and that was what led to my answer. – zyx Mar 25 '16 at 1:51
• @zyx: The disagreement I'm expressing lies in "no-one [...] should be accused of [...] moral posturing". Since my extensive attempts at convincing you to reformulate that part of your answer failed, I expressed my disagreement in an answer of my own. I wasn't implying anything about how often such accusations are leveled on the main site; I'm merely disagreeing with you leveling them here. – joriki Mar 25 '16 at 9:39