In this article we explore multiple change operators, i.e., operators in which the epistemic input is a set of sentences instead of a single sentence. We propose two types of change: prioritized change, in which the input set is fully accepted, and symmetric change, where both the epistemic state and the epistemic input are equally treated. In both kinds of operators we propose a set of postulates and we present different constructions: kernel changes and partial meet changes.

We propose a new class of multiple contraction operations — the system of spheres-based multiple contractions — which are a generalization of Grove’s system of spheres-based (singleton) contractions to the case of contractions by (possibly non-singleton) sets of sentences. Furthermore, we show that this new class of functions is a subclass of the class of the partial meet multiple contractions.

In the logic of theory change, the standard model is AGM, proposed by Alchourrón et al. (J Symb Log 50:510–530, 1985 ). This paper focuses on the extension of AGM that accounts for contractions of a theory by a set of sentences instead of only by a single sentence. Hansson (Theoria 55:114–132, 1989 ), Fuhrmann and Hansson (J Logic Lang Inf 3:39–74, 1994 ) generalized Partial Meet Contraction to the case of contractions by (possibly non-singleton) sets of sentences. In this (...) paper we present the possible worlds semantics for partial meet multiple contractions. (shrink)

Revision operation is the consistent expansion of a theory by a new belief-representing sentence. We consider that in a paraconsistent setting this desideratum can be accomplished in at least three distinct ways: the output of a revision operation should be either non-trivial or non-contradictory (in general or relative to the new belief). In this paper those distinctions will be explored in the constructive level by showing how the remainder sets could be refined, capturing the key concepts of paraconsistency in a (...) dynamical scenario. These are preliminaries results of a wider project on Paraconsistent Belief Change conduced by the authors. (shrink)

In this article we present a new class of multiple contraction functionswhich are a generalization of the epistemic entrenchment-based contractions (Grdenfors & Makinson, 1988) to the case of contractions by (possibly nonsingleton) sets of sentences and provide an axiomatic characterization for that class of functions. Moreover, we show that the class of epistemic entrenchment-based multiple contractions coincides with the class of system of spheres-based multiple contractions introduced in Fermé & Reis (2012).

Two of the most well-known belief contraction operators are partial meet contractions (PMCs) and kernel contractions (KCs). In this paper we propose two new classes of contraction operators, namely the class of generalized partial meet contractions (GPMC) and the class of generalized kernel contractions (GKC), which strictly contain the classes of PMCs and of KCs, respectively. We identify some extra conditions that can be added to the definitions of GPMCs and of GKCs, which give rise to some interesting subclasses of (...) those classes of functions, namely the classes of extensional and of uniform GPMCs/GKCs. In the context of contractions on belief sets the classes of partial meet contractions, uniform GPMCs and extensional GPMCs are all identical. Nevertheless, when considered as operations on belief bases, the class of uniform GPMCs coincides with the class of partial meet contractions, but the extensional GPMCs constitute a new kind of belief base contraction functions whose characterizing postulate of irrelevance of syntax is extensionality—the same postulate of irrelevance of syntax which occurs in the classical axiomatic characterization of partial meet contractions for belief sets—rather than the postulate of uniformity—which is the irrelevance of syntax postulate used in the axiomatic characterization for partial meet contractions on belief bases. Analogous results are obtained regarding the classes of extensional and of uniform GKCs. We present the interrelations in the sense of inclusion among all the new classes of operators presented in this paper and several well known classes of PMCs and of KCs. (shrink)

Uma boa entrevista precisa de uma entrada? Necessitamos aqui, realmente de uma apresentação de nosso entrevistado? Se sim, seremos sintéticos, porque estamos convencidos de que importa a fala de Renato Noguera. Deixaremos que a entrevista diga “algo” sobre ele que não possa ser pinçado rapidamente de seu currículo lattes, produção bibliográfica, palestras e bancas de trabalhos acadêmicos, não sem dizer, contudo, que Noguera é daqueles pensadores que aproximam o conhecimento das pessoas. Não escreve e nem fala como se estivesse em (...) uma Catedral, engomado e asséptico. Noguera é pop: dá entrevistas em programas de televisão com a mesma competência com a qual orienta seus estudantes, desenvolve pesquisas e escreve livros. Já há algum tempo, Renato Noguera é sinônimo de produção inovadora que contraria o epistemicídio negro e rasura as lacunas da filosofia. Nosso entrevistado engrossa as reflexões presentes nesta edição da revista Odeere/UESB, cujo tema central é “Afrofilosofias e saberes diaspóricos: Filosofias pretas nas palmas das mãos”, questionando silêncios de uma ciência branca-cis-euro-hetero-usa-normativa, pouco comprometida com a luta antirracista e a equanimidade. A ele agradecemos por nos conceder um pouco de seu tempo, tendo a internet nos servido de elo. A você dedicamos este trabalho, convidando-a a trilhar um percurso de leitura, o qual, se estivermos de acordo, apresentará: i) reflexão e avanço de conhecimento sobre uma filosofia negra; ii) outros caminhos para a filosofia, mais ao “sul”; iii) reinvenções de percurso de pesquisa, pois, ora, o entrevistado tem se voltado à filosofia para a infância. E por quê? Porque Erês, Ibejis, Exu Mirim, o menino Kiriku dão o que filosofar, tanto quanto Pinóquio, Mickey Mouse, Riquinho Rico ou o Pateta, não é mesmo? Esta entrevista não serve apenas aos estudiosos de filosofia, aos pesquisadores de categorias como raça, etnicidade e justiça cognitiva. Serve aquelxs interessadxs em ensinar e aprender filosofias negras, com vistas a denegrir a Vida numa articulação proativa e biocêntrica em favor da Comunidade. Em uma palavra: Ubuntu! Palavras chave: Filosofia; Afrocentricidade; África. (shrink)

In this paper, we propose and axiomatically characterize residual contractions, a new kind of contraction operators for belief bases. We establish that the class of partial meet contractions is a strict subclass of the class of residual contractions. We identify an extra condition that may be added to the definition of residual contractions, which is such that the class of residual contractions that satisfy it coincides with the class of partial meet contractions. We investigate the interrelations in the sense of (...) inclusion among the class of residual contractions and other classes of well known contraction operators for belief bases. (shrink)

A articulação entre psicanálise e hermenêutica não é algo de incomum no pensamento dos últimos anos, em especial a partir da segunda metade do século vinte. Ocorre, todavia, que essa articulação muito raramente é postulada como constitutiva ou intrínseca, se tomarmos em consideração os pressupostos da psicanálise freudiana comparativamente à filosofia da hermenêutica filosófica de Hans-Georg Gadamer. O presente artigo tem por objetivo pavimentar essa clareira comum entre ambos, tomando como base a interpretação na especificidade da clínica do inconsciente e (...) do compreender gadameriano. (shrink)