To be clear, I didn't object at all to discussing the problem RWG encountered with Math StackExchange (MSE) — they could potentially affect any of us. (I just missed having more of a discussion about the math Bill posted.) There are two reasons occurring to me that these problems happen on MSE. One is that it's so big and anonymous that the people on it often don't know each other or even e-know e-chother. The other is that some people see their role as one of enforcing rules, and some such people don't bother to make sure their enforcing is reasonable. (Sometimes called "authoritarian personalities".) Let g(a,b) denote the circumference of the ellipse (x/a)^2 + (y/b)^2 = 1. Is there an closed expression for ∂g/∂a or ∂^2g/∂a∂b ? —Dan Fred Lunnon wrote: ----- << The mathematics is more interesting than the politics of math.stackexchange. >> Agreed; but politics has an unpleasant habit of intruding on our interests uninvited. RWG ain't the first to fall victim to this particular unforeseen consequence, and sure as eggs is eggs, he won't be the last. I thought WGD's analysis informative and convincing, as far as it goes --- and a salutary reminder of how fortunate we are to have math-fun run as smoothly as it does! No doubt most people on this list will sympathise heartily with a Q&A site attempting to avoid transformation into a free online plagiarism factory. So why do such efforts regularly and spectacularly backfire in this fashion? One factor --- difficult to combat --- is exemplified by the experience of a chess IM acquaintance who once found himself playing, for the team representing a very small country, on top board against Anatoly Karpov. He reported that the world champion just sat there, (apparently) aimlessly shunting rooks to and fro along the back rank, until it suddenly dawned on yer man that (as he put it) "his options had run out". For chess, the score line is eventually on hand to distinguish between naïve incompetence and incomprehensible superiority; however in mathematics, as in many real-life situations, a convenient discrimination algorithm is often unavailable. << As for the five who jumped me: "Off topic" my asymptote. >> Another recurrent feature --- on the face of it, much easier to fix --- is implicit segregation. When the club doorman refuses you entry on the grounds that you have the wrong sex, colour, religion, age, etc. you might well consider such discrimination unacceptable, but at least you know where you stand and can consider constructively how to resolve the situation. If he attempts to avoid confrontation by concocting some obviously irrelevant excuse, you are merely left bewildered and possibly angry. In a more straightforward world, SE would simply call a spade a spade: apologetically admit that an enquiry appeared potentially plagiaristic, before requesting supporting evidence that it was genuine (background, citations, etc). By attempting to avoid offending a small army of cheats, they manage instead to upset the very people they (presumably) want onboard. ... -----