Online research in philosophy

I advance an objection to Graham Priest’s account of fictional entities as nonexistent objects. According to Priest, fictional characters do not have, in our world, the properties they are represented as having; for example, the property of being a bank clerk is possessed by Joseph K. not in our world but in other worlds. Priest claims that, in this way, his theory can include an unrestricted principle of characterization for objects. Now, some representational properties attributed to fictional characters, a kind of fictional entities, involve a crucial reference to the world in which they are supposed to be instantiated. I argue that these representational properties are problematic for Priest’s theory and that he cannot accept an unrestricted version of the principle of characterization. Thus, while not refuting Priest’s theory, I show that it is no better off than other Meinongian theories.

Badici [2008] criticizes views of Priest [2002] concerning the Inclosure Schema and the paradoxes of self-reference. This article explains why his criticisms are to be rejected.

Logic is often perceived as having little to do with the rest of philosophy, and even less to do with real life. In this lively and accessible introduction, Graham Priest shows how wrong this conception is. He explores the philosophical roots of the subject, explaining how modern formal logic deals with issues ranging from the existence of God and the reality of time to paradoxes of probability and decision theory. Along the way, the basics of formal logic are explained in simple, non-technical terms, showing that logic is a powerful and exciting part of modern philosophy.

In Philosophical Logic, the Liar Paradox has been used to motivate the introduction of both truth value gaps and truth value gluts. Moreover, in the light of “revenge Liar” arguments, also higher-order combinations of generalized truth values have been suggested to account for so-called hyper-contradictions. In the present paper, Graham Priest's treatment of generalized truth values is scrutinized and compared with another strategy of generalizing the set of classical truth values and defining an entailment relation on the resulting sets of higher-order values. This method is based on the concept of a multilattice. If the method is applied to the set of truth values of Belnap's “useful four-valued logic”, one obtains a trilattice, and, more generally, structures here called Belnap-trilattices. As in Priest's case, it is shown that the generalized truth values motivated by hyper-contradictions have no effect on the logic. Whereas Priest's construction in terms of designated truth values always results in his Logic of Paradox, the present construction in terms of truth and falsity orderings always results in First Degree Entailment. However, it is observed that applying the multilattice-approach to Priest's initial set of truth values leads to an interesting algebraic structure of a “bi-and-a-half” lattice which determines seven-valued logics different from Priest's Logic of Paradox.

Graham Priest presents a ground-breaking account of the semantics of intentional language--verbs such as "believes," "fears," "seeks," or "imagines." Towards Non-Being proceeds in terms of objects that may be either existent or non-existent, at worlds that may be either possible or impossible. The book will be of central interest to anyone who is concerned with intentionality in the philosophy of mind or philosophy of language, the metaphysics of existence and identity, the philosophy of fiction, the philosophy of mathematics, or cognitive representation in AI.

Validity : what follows from what? -- Truth functions,or not -- Names and quantifiers : is nothing something? -- Descriptions and existence : did the greeks worship Zeus? -- Self-reference : what is this chapter about? -- Necessity and possibility : what will be must be? -- Conditionals: what's in an if? -- The future and the past : is time real?? -- Identity and change : is anything ever the same? -- Vaguenes : how do you stop sliding down a slippery slope? -- Probability : the strange case of the missing reference class? -- Inverse probability : you can't be indifferent about it! -- Decision theory : great expectations? -- A little history and some further reading?

In ‘Towards a Solution to the Sorites Paradox’, Graham Priest gives us a new account of the sorites based on fuzzy logic. The novelty lies in the suggestion that truth-value assignments should themselves be treated as fuzzy objects, i.e., objects about which we can make fuzzy identity statements. I argue that Priest’s solution does not have the explanatory force that Priest advocates. That is, it does not explain why we find the existence of a cut-off point counter-intuitive. I also argue that this sort of explanation calls for a general theory that goes beyond the special case of linguistic vagueness, for the phenomenon is at bottom not linguistic.

Graham Priest's book In Contradiction (Dordrecht: Martinus Nijhoff, 1987) is a bold and well argued for defense of the existence of true contradictions. Priest's case for true contradictions -- or «dialetheias», as he calls them -- is by no means the only one in contemporary analytical philosophy, let alone in philosophy tout court . In some sense, other defenses of the existence of true contradictions are less philosophically «heterodox» than his is, since, unlike Priest's orientation, other approaches are closer to prevailing ideas in mainstream («Quinean») analytical philosophy, whereas Priest's leanings are strongly anti realist, and not distant from the logical empiricism of the thirties.

The present article critically examines three aspects of Graham Priest's dialetheic analysis of very important kinds of limitations (the limit of what can be expressed, described, conceived, known, or the limit of some operation or other). First, it is shown that Priest's considerations focusing on Hegel's account of the infinite cannot be sustained, mainly because Priest seems to rely on a too restrictive notion of object. Second, we discuss Priest's treatment of the paradoxes in Cantorian set-theory. It is shown that Priest does not address the issue in full generality; rather, he relies on a reading of Cantor which implicitly attributes a very strong principle concerning quantification over arbitrary domains to Cantor. Third, the main piece of Priest's work, the so-called “inclosure schema”, is investigated. This schema is supposed to formalize the core of many well-known paradoxes. We claim, however, that formally the schema is not sound.