18 APhEx num 18, anno 2018

Di recente la nozione di verità parziale ha attirato l'attenzione di filosofi e logici. Questa nota presenta brevemente un problema che una teoria della verità parziale deve risolve e discute alcuni tentativi di soluzione.

Margaret Gilbert (1942) is a British philosopher, full professor in Moral Philosophy at Irvine University (CA) since 2006. Gilbert is one of the leading philosophers in the field of social ontology. In 1989, in On Social Fact, she elaborated the plural subject theory. Since then, in the following thrity years she went on refining this theory, applying it to different fields ranging from political philosophy to epistemology. At present, her research focuses on the notion of joint commitment and on issues concerning rights and duties embedded in sociality.

According to anti-exceptionalists, logical laws do not enjoy any privileged epistemological or metaphysical status, and the choice between rival logical theories should be carried out by means of an abductive methodology (§1). We will try to clarify which properties antiexceptionalists want to deprive logic of (§2), review the main implementations of the abductive model (§3), and clarify its criteria (§4). Along the way, we will highlight some of the difficulties the position seems to face; as we will see, many among these consist in circularity objections.

Composition is a relation that holds between pluralities of objects and particular objects. Composition seems to have many analogies with identity relation, and some philosophers suggest to consider the first a particular case of the second: in a nutshell, composition would be identity. Mereology and plural logic are needed to develop this intuition in a perspicuous way. Despite the arguments for the identity of the two relations, there are nevertheless some objections strong enough to maintain that composition and identity are two distinct relations, and they are characterized by different principles.

This book introduces the main concepts and formal issues about modal logics, while also engaging the major philosophical debates such formal systems gave rise to. In Chapters I and II, Marcello Frixione presents the notion of a possible world from the standpoint of some theoretical problems in the philosophy of language and shows how a possible world semantics is applied to the main systems of alethic modal logic. In Chapters III and IV, Samuele Iaquinto introduces deontic, tense, conditional, and epistemic logics. In Chapters V, VI, and VII Massimiliano Vignolo addresses quantified modal logic and the main philosophical issues it gives rise to, such as the construal of de re modal statements and the problem of mere possibilia.