 The developments of the last decade take on board the suggestion (see Mancosu 2008b) to follow a “bottom up” approach to mathematical explanation, investigating cases considered explanatory in mathematical practice and resisting the temptation to argue “top down” by proposing encompassing approaches to mathematical explanation without a previous extensive analysis of individual case studies. However, interest in the “top down” approaches is still lively and informs the discussion of many particular case studies. Apart from a single dissenting voice (Zelcer 2013, see also the reply Weber and Frans 2017), contributors in this area all accept mathematical explanation of mathematical facts as a datum about mathematical practice that philosophers of mathematics have to investigate. 