Mathesis Universalis from Leibniz to Husserl

The idea of a mathesis universalis plays a prominent role in Edmund Husserl’s Formal and Transcendental Logic (FTL). It is clear that at this mature stage of his philosophy the idea he refers to with “mathesis universalis” is in large part due to Husserl’s own development and cannot be straightforwardly derived from one single author or source anymore. In a historical respect, of course, the idea is most strongly associated with Leibniz, and indeed we see that Husserl does re- fer repeatedly to him in FTL when discussing the mathesis universalis (e.g. § 23b). However, Leibniz is not the only author that is relevant for the specific way in which Husserl fills out the notion of mathesis universalis, since he also repeatedly refers to more recent 19th century authors such as Bolzano and Lotze, as well as early modern authors such as Vieta and Descartes. Here, as elsewhere, we see Husserl’s eclecticism at work.