One aspect of critical reasoning is the analysis and appraisal of claims and arguments. A typical problem, when analysing and appraising arguments, is inconsistent statements. Although several inconsistencies may have deleterious effects on rationality and action, not all of them do. As educators, we also have an obligation to teach this evaluation in a way that does justice to our normal reasoning practices and judgements of inconsistency. Thus, there is a need to determine the acceptable inconsistencies from those that are not, and to impart that information to students. We might ask: What is the best concept of inconsistency for critical reasoning and pedagogy? While the answer might appear obvious to some, the history of philosophy shows that there are many concepts of “inconsistency”, the most common of which comes from classical logic and its reliance on opposing truth-values. The current exemplar of this is the standard truth functional account from propositional logic. Initially, this conception is shown to be problematic, practically, conceptually and pedagogically speaking. Especially challenging from the classical perspective are the concepts of ex contradictione quodlibet and ex falso quodlibet. The concepts may poison the well against any notion of inconsistency, which is not something that should be done unreflectively. Ultimately, the classical account of inconsistency is rejected. In its place, a semantic conception of inconsistency is argued for and demonstrated to handle natural reasoning cases effectively. This novel conception utilises the conceptual antonym theory to explain semantic contrast and gradation, even in the absence of non-canonical antonym pairs. The semantic conception of inconsistency also fits with an interrogative argument model that exploits inconsistency to display semantic contrast in reasons and conclusions. A method for determining substantive inconsistencies follows from this argument model in a 4 straightforward manner. The conceptual fit is then incorporated into the pedagogy of critical reasoning, resulting in a natural approach to reasoning which students can apply to practical matters of everyday life, which include inconsistency. Thus, the best conception of inconsistency for critical reasoning and its pedagogy is the semantic, not the classical. / Philosophy Practical and Systematic Theology / D. Phil

Orientador: Marcelo Esteban Coniglio / Dissertação (mestrado) - Universidade Estadual de Campinas, Instituto de Filosofia e Ciencias Humanas / Made available in DSpace on 2018-08-17T03:29:03Z (GMT). No. of bitstreams: 1 Rodrigues_TarcisioGenaro_M.pdf: 1141020 bytes, checksum: 59bb8a3ae7377c05cf6a8d8e6f7e45a5 (MD5) Previous issue date: 2010 / Resumo: A Programação Lógica nasce da interação entre a Lógica e os fundamentos da Ciência da Computação: teorias de primeira ordem podem ser interpretadas como programas de computador. A Programação Lógica tem sido extensamente utilizada em ramos da Inteligência Artificial tais como Representação do Conhecimento e Raciocínio de Senso Comum. Esta aproximação deu origem a uma extensa pesquisa com a intenção de definir sistemas de Programação Lógica paraconsistentes, isto é, sistemas nos quais seja possível manipular informação contraditória. Porém, todas as abordagens existentes carecem de uma fundamentação lógica claramente definida, como a encontrada na programação lógica clássica. A questão básica é saber quais são as lógicas paraconsistentes subjacentes a estas abordagens. A presente dissertação tem como objetivo estabelecer uma fundamentação lógica e conceitual clara e sólida para o desenvolvimento de sistemas bem fundados de Programação Lógica Paraconsistente. Nesse sentido, este trabalho pode ser considerado como a primeira (e bem sucedida) etapa de um ambicioso programa de pesquisa. Uma das teses principais da presente dissertação é que as Lógicas da Inconsistência Formal (LFI's), que abrangem uma enorme família de lógicas paraconsistentes, proporcionam tal base lógica. Como primeiro passo rumo à definição de uma programação lógica genuinamente paraconsistente, demonstramos nesta dissertação uma versão simplificada do Teorema de Herbrand para uma LFI de primeira ordem. Tal teorema garante a existência, em princípio, de métodos de dedução automática para as lógicas (quantificadas) em que o teorema vale. Um pré-requisito fundamental para a definição da programação lógica é justamente a existência de métodos de dedução automática. Adicionalmente, para a demonstração do Teorema de Herbrand, são formuladas aqui duas LFI's quantificadas através de sequentes, e para uma delas demonstramos o teorema da eliminação do corte. Apresentamos também, como requisito indispensável para os resultados acima mencionados, uma nova prova de correção e completude para LFI's quantificadas na qual mostramos a necessidade de exigir o Lema da Substituição para a sua semântica / Abstract: Logic Programming arises from the interaction between Logic and the Foundations of Computer Science: first-order theories can be seen as computer programs. Logic Programming have been broadly used in some branches of Artificial Intelligence such as Knowledge Representation and Commonsense Reasoning. From this, a wide research activity has been developed in order to define paraconsistent Logic Programming systems, that is, systems in which it is possible to deal with contradictory information. However, no such existing approaches has a clear logical basis. The basic question is to know what are the paraconsistent logics underlying such approaches. The present dissertation aims to establish a clear and solid conceptual and logical basis for developing well-founded systems of Paraconsistent Logic Programming. In that sense, this text can be considered as the first (and successful) stage of an ambitious research programme. One of the main thesis of the present dissertation is that the Logics of Formal Inconsistency (LFI's), which encompasses a broad family of paraconsistent logics, provide such a logical basis. As a first step towards the definition of genuine paraconsistent logic programming we shown, in this dissertation, a simplified version of the Herbrand Theorem for a first-order LFI. Such theorem guarantees the existence, in principle, of automated deduction methods for the (quantified) logics in which the theorem holds, a fundamental prerequisite for the definition of logic programming over such logics. Additionally, in order to prove the Herbrand Theorem we introduce sequent calculi for two quantified LFI's, and cut-elimination is proved for one of the systems. We also present, as an indispensable requisite for the above mentioned results, a new proof of soundness and completeness for first-order LFI's in which we show the necessity of requiring the Substitution Lemma for the respective semantics / Mestrado / Filosofia / Mestre em Filosofia