 The recent publication of Stumpf’s habilitation thesis Über die Grundsätze der Mathematik raises many questions which have been the subject of recent commentaries. (D. Münch, 2002–2003; W. Ewen, 2008; C. Ierna, 2015). Stumpf’s habilitation thesis focuses on the nature and origins of mathematical principles or axioms. Its starting point rests on the following question: