In this essay a theory of proper names is developed and applied to the construction of quantified modal logics and to a discussion of problems concerning identity across possible worlds. The theory is then used to aid discussion of essentialism, empty singular terms, quantification into epistemic contexts, and Frege' s problem with identity . In the first chapter, after a preliminary discussion of Russell's and Frege's theories of names, a theory is developed. It is argued that in the giving of a name a relation is established between the name and what is named. That relation is the sense of the name. It is also argued that names can be given to imaginary, fictional, and other such non-existent things. The second chapter is devoted to a discussion of Quine's programme for eliminating singular terms. It is there argued that the programme cannot be justified. The third chapter centres around the construction of logical systems to deal with identity across possible worlds. It is assumed that once a name is given and its sense thereby established the name is a rigid designator. Quantificational systems are constructed without modal operators yet in terms of which cross world identity can be discussed. Modal operators are then introduced to facilitate a discussion of essentialism and identity. At each point the formal systems are constructed in accordance with clearly stated assumptions about constant singular terms, the domains of quantification, and the interpretation of modal operators.

No description available.

Thesis (M.A.)--Memorial University of Newfoundland, 2005. / Bibliography: leaves 64-70.

This research examines how cross-modal and within-modal matching differ. Three broad classes of difference are considered, that crossmodal matching requires (a) "translation" between modality-specific stores or (b) "transformation" of information when different information is available through each modality or (c) transformation, whatever the information available through each modality, owing to differences in encoding strategy. Visual-kinaesthetic matching of the end-point of lever movements has been investigated. It is argued that adult cross-modal performance depends on information and strategy, not directly on modality. Results with children have been less clear, experiments were therefore undertaken, with subjects aged 6-9 years. The hypothesis was that childrens' performance also would be determined by available information, and strategy. With information differences eliminated, modality conditions did not differ in within-subject variability, with up to 20 second unfilled retention intervals. With visual information enhanced by background cues and emphasis of the body midline, visual matching was superior to kinaesthetic, and within-modal was superior to cross-modal matching. These differences disappeared with practice, together with coding relative to the midline in the cross-modal conditions. Midline-relative coding was the norm with the midline emphasised, and without background cues. With or without variability differences, VV did not differ from KK in bias, but KV resulted in greater overshooting, VK greater undershooting. The most likely explanation is resistance to movement when perception is kinaesthetic, causing overestimation of distance moved. Consideration of the information normally available to subjects, generated the hypothesis that temporal and spatial parameters should interact more with kinaesthetic than with visual perception. This was supported, since movement velocity biased only kinaesthetic judgements. It is concluded that matching performance depends on the information encoded and used as the basis of matching, which depends on strategy; strategy depends on information (a) available during stimulus presentation, (b) normally available in each modality, (c) which it is anticipated will be available during response.

Modal logics have found applications in many diferent contexts. For example, epistemic modal logics can be used to reason about security protocols, temporal modal logics can be used to reason about the correctness of distributed systems and propositional dynamic logic can reason about the correctness of programs. However, pure modal logic is expressively weak and cannot represent many interesting secondorder properties that are expressible, for example, in the μ-calculus. Here we investigate the extension of modal logics with propositional quantification modulo bisimulation (bisimulation quantification). We extend existing work on bisimulation quantified modal logic by considering the variety of logics that result by restricting the structures over which they are interpreted. We show this can be a natural extension of modal logic preserving the intuitions of both modal logic and propositional quantification. However, we also find cases where such intuitions are not preserved. We examine cases where the axioms of pure modal logic and propositional quantification are preserved and where bisimulation quantifiers preserve the decidability of modal logic. We translate a number of recent decidability results for monadic second-order logics into the context of bisimulation quantified modal logics, and show how these results can be used to generate a number of interesting bisimulation quantified modal logics.

Zugl.: Rostock, Univ., Habil.-Schr.

Research. Thesis (M.Sc.)--University of Melbourne, Dept. of Computer Science and Software Engineering, 2006. / Typescript. Includes bibliographical references (leaves 163-170).

Thesis (doctoral)--Universität, Tübingen, 2003.

Orientador: Itala Maria Loffredo D'Ottaviano / Dissertação (mestrado) - Universidade Estadual de Campinas, Instituto de Filosofia e Ciências Humanas / Made available in DSpace on 2018-08-19T03:32:32Z (GMT). No. of bitstreams: 1 Almeida_DanteCardosoPintode_M.pdf: 571204 bytes, checksum: 5d6a5ced0609a9ec16f84bc5badb751d (MD5) Previous issue date: 2011 / Resumo: Esta dissertação tem como objetivo a análise de um resultado em lógica aléticoepistêmica, divulgado por Frederic Fitch em 1963, conhecido como Paradoxo da Cognoscibilidade. Segundo este resultado, se todas verdades podem ser conhecidas, então todas verdades são conhecidas. Isto sugere que há alguma verdade impossível de ser conhecida. Descrevemos, nesta dissertação, a lógica modal alética e a epistêmica, que consistem em recursos formais requeridos para a análise do Paradoxo. Também esclarecemos o papel deste no debate filosófico entre as correntes de pensamento realistas e antirealistas. Apontamos e analisamos duas propostas de solução do Paradoxo mais discutidas na literatura. Como principal ojetivo desta dissertação, investigamos o Paradoxo da Cognoscibilidade em sistemas multiagentes. Demonstramos que, apesar de em tais sistemas o Paradoxo ser minimizado, ele ainda não é completamente resolvido. Por fim, também apresentamos várias formas de obter a contraparte doxástica do Resultado, conhecida como Paradoxo da Credibilidade / Abstract: This text studies a result in epistemic-alethic logic, published by Frederic Fitch in 1963, known as Knowability Paradox. According to this result, if all truths are knowable, then all truths are known. This suggests there are unknowable truths. We describe alethic and epistemic modal logics, which are formal resources required in order to study the paradox. Also, we examine its role in the philosophical debate between realists and anti-realists. We point out and analize two attempts to solve the Paradox. The main aim of this text is to explore the Knowability Paradox in multi-agents systems. We shoe that, although in these systems the Paradox is weaker, it's not entirely solved. We also show many ways to derive the doxastic counterpart of the result, known as Belivability Paradox / Mestrado / Filosofia / Mestre em Filosofia

Orientador: Lucas Angioni / Tese (doutorado) - Universidade Estadual de Campinas, Instituto de Filosofia e Ciências Humanas / Made available in DSpace on 2018-08-20T11:18:44Z (GMT). No. of bitstreams: 1 Ferreira_MateusRicardoFernandes_D.pdf: 823119 bytes, checksum: 7ba656176385de662b9d8593f14aa89d (MD5) Previous issue date: 2012 / Resumo: Nesta tese discuto aspectos da logica de Aristóteles que sao ressaltados por abordagens contemporâneas dos Primeiros Analíticos e que mostram uma teoria mais rica e sutil do que tradicionalmente se entende como sendo a lógica aristotelica. Em especial, abordo teses sobre como devem ser compreendidas as proposições categóricas, o que sao precisamente silogismos, o que sao silogismos perfeitos e quais problemas enfrenta a parte da lógica de Aristoteles que lida com proposicoes modais. Nessa direcao, abordo evidencias textuais para duas concepcoes de proposicao categorica e as dificuldades para coaduna-las com as proposicoes singulares. Alem disso, argumento que silogismos devem ser compreendidos como cadeias de predicacoes e que Aristoteles concebe um sistema logico quando procura justificar quais arranjos entre termos formam de fato tais cadeias. Argumento, tambem, que os silogismos perfeitos sao evidentes nesse sistema nao porque considerados indemonstraveis, mas porque podem ser deduzidos a partir de definicoes das proposicoes categoricas e de certas regras gerais, isto e, de regras aplicaveis nao apenas a um tipo de proposicao categorica. Por fim, apresento as caracteristicas gerais e as dificuldades de uma parte da logica de Aristoteles muito pouco associada a logica aristotelica como tradicionalmente entendida: a silogistica modal / Abstract: The present dissertation discusses aspects of Aristotle's Logic which are enhanced by contemporary approaches to Prior Analytics and display a logical theory richer and subtler than what traditionally is comprehended as being the Aristotelian Logic. My main claims concern how categorical propositions must be understood, what is the exact nature of syllogisms, what is a perfect syllogism, as well as some questions in the part of Aristotelian Logic which deals with modal propositions. From an examination of texts that support two different conceptions of categorical proposition, I discuss the difficulties in adjusting each of them to singular propositions. I also argue that syllogisms must be comprehended as chains of predications and that Aristotle conceives a logical system when he proceeds to justify which terms arrangement does produce chains of the required kind. I also argue that in this system perfect syllogisms must be understood as evident not because they are unproved, but because they are deduced from definitions for categorical propositions and from general rules, i.e. rules not applied just to some categorical propositions. Finally, I discuss general features and problems concerning a part of Aristotle's Logic rarely attached to the Aristotelian Logic as traditionally comprehended: the modal syllogistic / Doutorado / Filosofia / Doutor em Filosofia