Title Text:Mathematicians give a third answer on the vertical axis, “That question is poorly defined, but we have a sub-field devoted to every plausible version of it.” Origin:https://xkcd.com/1991/ https://www.explainxkcd.com/wiki/index.php/1991:_Research_Areas_by_Size_and_Countedness 研究领域进展 但数学家在纵轴上给出了第三种情况，“这个问题的定义很糟糕，但我们有一个子领域，专门研究它的每一个可能的版本。” https://mp.weixin.q… Read more