This book presents novel formalizations of three of the most important medieval logical theories: supposition, consequence and obligations. In an additional fourth part, an in-depth analysis of the concept of formalization is presented - a crucial concept in the current logical panorama, which as such receives surprisingly little attention.Although formalizations of medieval logical theories have been proposed earlier in the literature, the formalizations presented here are all based on innovative vantage points: supposition theories as algorithmic hermeneutics, theories of consequence analyzed (...) with tools borrowed from model-theory and two-dimensional semantics, and obligations as logical games. For this reason, this is perhaps the first time that these medieval logical theories are made fully accessible to the modern philosopher and logician who wishes to obtain a better grasp of them, but who has always been held back by the lack of appropriate ‘translations' into modern terms.Moreover, the book offers a reflection on the very nature of logic, a reflection that is prompted by the comparisons between medieval and modern logic, their similarities and dissimilarities. It is thus a contribution not only to the history of logic, but also to the philosophy of logic, the philosophy of language and semantics.The analysis of medieval logic is also relevant for the modern philosopher and logician in that, being the unifying methodology used across all disciplines at that time, logic really provided unity to science. It thus presents a unified model of scientific investigation, where logic plays the aggregating role. (shrink)

In his commentaries on Porphyry and Aristotle’s Organon and in his other works, John Duns Scotus shows his knowledge of both the modistic theory of language and the theory of supposition. My contribution sheds some light on the relationship between Scotus’ philosophy of language and the theory of supposition, collecting and commenting on all the passages in which he makes use of it or discusses some theoretical points. I take into special account the almost unknown commentary on the Topics, which (...) is preserved in a Vatican manuscript. (shrink)

This study comments on six notabilia found in the general observations with which Brinkley begins his treatise on supposition in his Summa logicae: i) the logico-metaphysical explanation of the distinction between significatio and suppositio, ii) the ontic division principle of supposition, iii) the relationship between supposita and truth-makers, iv) what seems to be a late resurgence of natural supposition, v) a pragmatic suspension of the regula appellationum and vi) Brinkley’s apparently incompatible claims that there are communicable things and that there (...) are only singular things, a position that is a medieval form of immanent realism. Based on the two manuscripts that contain the treatise on supposition, an appendix offers a provisional edition of part of Brinkley’s Summa, a collaboration between the author and Joël Lonfat. (shrink)