14526

SoSe 15: Aristotle and Avicenna: Modal Syllogistics

Lukas Mühlethaler, Stephen Menn

Additional information / Pre-requisites

All primary texts will be made available in English translation. No knowledge of Greek or Arabic is required, only some basic familiarity with Aristotelian syllogistic and with modern symbolic systems, and a willingness to explore their possibilities. The professors intend to speak in English, but participants are welcome to speak in German. close

Comments

Aristotle's modal syllogistic is often thought to be incoherent; often the diagnosis is given that he does not distinguish between de re and de dicto modalities. Thus Aristotle accepts the conversion rule "some A is necessarily B, therefore some B is necessarily A," which seems to hold only for de dicto necessity, but he also accepts the syllogism "every A is B, every B is necessarily C, therefore every A is necessarily C," which seems to hold only for de re necessity. But even if Aristotle does not succeed in producing a unified system of modal syllogistic, he at least takes major steps toward clarifying the modal notions and their consequence-relations. And there have been repeated attempts to save or reconstruct Aristotle's modal syllogistic as a system, without relying on a de re/de dicto distinction. The most important such attempts were, in the middle ages, by Avicenna (and then by later Arabic philosophers developing and sometimes criticizing Avicenna), and, in recent years, in Marko Malink's formal reconstruction in his book Aristotle's Modal Syllogistic. Malink's work has sparked a rebirth of interest in Aristotle's modal syllogistic. Independently, in recent years, Avicennian and post-Avicennian theories of modality (in syllogistic and metaphysics) have emerged at the center of interest in the history of Arabic philosophy. It is natural to compare medieval and contemporary ways of saving or reconstructing Aristotle's modal syllogistic, and also to see whether different formal reconstructions can bring out the differences between the different medieval options in modal syllogistic, or what limits such formal reconstructions may face. (Avicenna's system differs from any of the modern reconstructions of Aristotle in that-at least in Avicenna's first formulation-it essentially involves time, and does not contain a pure assertoric [non-modal] syllogistic as a subsystem.) While we will focus on modal syllogistic, we will if possible also look at the metaphysical foundations or applications of modality, which are especially important for Avicenna. In June many of the leading scholars in both Aristotelian and Arabic modal syllogistic will be in Berlin for a series of workshops; they will attend our seminar when they can, and participants in the seminar will gain the background to participate in those workshops. close