 There are several recent works on Aristotle’s modal syllogistics, but no generally accepted historical reconstruction which would make it a coherent theory. It was apparently based on various assumptions which were not fully compatible (Hintikka 1973; Smith 1989; Striker 2009). Some commentators have been interested in finding coherent layers of the theory by explicating them in terms of Aristotle’s other views (van Rijen 1989; Patterson 1995). There are also several formal reconstructions such as Rini 2011 (modern predicate logic), Ebert and Nortmann 2007 (possible worlds semantics), and various set-theoretical approaches discussed in Johnson 2004 and Malink 2006, 2013 (mereological semantics).