Online research in philosophy

Context is a concept used by philosophers and scientists with many different definitions. Since Dummett we speak of "context principle" in Frege and Wittgenstein: "an expression has a meaning only in the context of a sentence". The context principle finds an extension in some of Wittgenstein's ideas, especially in his famous passage where he says that "to understand a sentence is to understand a language". Given that Wittgenstein believes that "the" language does not exist but only language games exist, we should conclude that he is speaking of the need to consider any sentence always in the context of a language game1. This general attitude is certainly attuned with the contemporary tendency to place contextual restrictions to the interpretations of our sentences. However we find so many kinds and forms of restrictions that this general attitude is not enough to give us a viable tool to find an order in the web of so many different theories of context. To look for an order or, at least a clarification, we may start with two contrasting paradigms of theories: the "objective" theory of contexts, where context is a set of features of the world, and the "subjective" theories of context, where context is the cognitive background of a speaker or agent in respect to a situation2. We have here not only two different ways of using the term "context" but also two different conceptions of semantics and philosophy. The different conceptions are normally associated, respectively, with the classical paradigm of model theoretic semantics (Kaplan, Lewis Stalnaker) on one hand and with the A.I. paradigm (McCarthy, Buvac, Giunchiglia) on the other hand. For sake of simplicity I will restrict my attention3 mainly to Kaplan 1989 and to McCarthy 1993 and Giunchiglia 1993. The two different conceptions can be summarised with the following schema: a) context as: set of features of the world..

This paper proposes a formalization of ability that is motivated in part by linguistic considerations and by the philosophical literature in action theory and the logic of ability, but that is also meant to match well with planning formalisms, and so to provide an account of the role of ability in practical reasoning. Some of the philosophical literature concerning ability, and in particular [Austin, 1956], suggests that some ways of talking about ability are context-dependent. I propose a way of formalizing this dependency.

This thesis deals with the phenomenon of attitude reporting. More specifically, it provides a unified semantics of de re and de se belief reports. After arguing that de se belief is best thought of as a special case of de re belief, I examine whether we can extend this unification to the realm of belief reports. I show how, despite very promising first steps, previous attempts in this direction ultimately fail with respect to some relatively recent linguistic data involving quantified and infinitival reports, logophoric constructions, and monstrously shifted indexicals. Formalizing my idea of a contextual resolution of acquaintance relations in a dynamic framework, I arrive at an alternative analysis that handles all these data.

This is a review of the above title published by Ablex Publishing Corporation, Norwood, New Jersey, 1990; vi + 256 pages, hardback, ISBN 0{89391{535{1 (Library of Congress: Q335.M38 1989), edited by Vladimir Lifschitz.

We focus on how we should define the relevance of information to a context for information processing agents, such as oracles. We build our formalization of relevance upon works in pragmatics which refer to contextual information without giving any explicit representation of context. We use a formalization of context (due to us) in Situation Theory, and demonstrate its power in this task. We also discuss some computational aspects of this formalization.

At the heart of natural language processing is the understanding of context dependent meanings. This paper presents a preliminary model of formal contexts based on situation theory. It also gives a worked-out example to show the use of contexts in lifting, i.e., how propositions holding in a particular context transform when they are moved to another context. This is useful in NLP applications where preserving meaning is a desideratum.

These notes discuss formalizing contexts as first class objects. The basic relationships are: ist(c,p) meaning that the proposition p is true in the context c, and value(c,p) designating the value of the term e in the context c Besides these, there are lifting formulas that relate the propositions and terms in subcontexts to possibly more general propositions and terms in the outer context. Subcontextx are often specialised with regard to time, place and terminology. Introducing contexts as formal objects will permit axiomatizations in limited contexts to be expanded to transcend the original limitations. This seems necessary to provide AI programs using logic with certain capabilities that human fact representation and human reasoning possess. Fully implementing transcendence seems to require further extensions to mathematical logic, ie. beyond the nonmonotonic inference methods first invented in AI and now studied as a new domain of logic.

This is a review of Formalizing Common Sense: Papers by John McCarthy, ed. by Vladimir Lifschitz, published by Ablex Publishing Corp. in 1990.

The issue of context arises in assorted areas of Artificial Intelligence. Although its importance is realized by various researchers, there is not much work towards a useful formalization. In this paper, we will present a preliminary model (based on Situation Theory) and give examples to show the use of context in various fields, and the advantages gained by the acceptance of our proposal.