Two systems of belief change based on paraconsistent logics are introduced in this paper by means of AGM-like postulates. The first one, AGMp, is defined over any paraconsistent logic that extends classical logic such that the law of excluded middle holds w.r.t. the paraconsistent negation. The second one, AGM•, is specifically designed for paraconsistent logics known as Logics of Formal Inconsistency (LFIs), which have a formal consistency operator which allows to recover all the classical inferences. Besides the three usual operations over belief sets, namely expansion, contraction and revision (which is obtained from contraction by the Levi identity), the underlying paraconsistent logic allows us to define additional operations involving (non-explosive) contradictions. Thus, it is defined external revision (which is obtained from contraction by the reverse Levi identity), consolidation and semi-revision, all of them over belief sets. It is worth noting that the latter operations, introduced by S. Hansson, involve the temporary acceptance of contradictory beliefs, and so they were originally defined only for belief bases. Unlike to previous proposals in the literature, only defined for specific paraconsistent logics, the present approach can be applied to a general class of paraconsistent logics which are supraclassical, thus preserving the spirit of AGM. Moreover, representation theorems w.r.t. constructions based on selection functions are obtained for all the operations.

Qual o lugar da filosofia nos dias atuais? Diante das inúmeras respostas possíveis a esta questão, nos debruçaremos em alguns tópicos que podemos inserir na chamada Ética Informacional, um ramo de investigação filosófico-interdisciplinar relativamente recente que discute problemas oriundos da relação ser humano/tecnologias digitais. Temas como privacidade informacional, arrogância epistêmica e divisão digital serão discutidos e relacionados, com o intuito de ilustrar o papel da filosofia na compreensão da complexidade inerente às dinâmicas sociais no contexto da sociedade da informação. Argumentaremos que pensar o mundo contemporâneo a partir do viés da ética informacional se faz cada dia mais imprescindível para que possamos entrar em sintonia com as rápidas mudanças que a revolução informacional impõe à vida em sociedade e não sermos levados pelas enxurradas informacionais que presenciamos diariamente.

The main purpouse of this dissertation is the proposal of a solution to some paradoxes related to deontic logic presented in the literature, also known as deontic dilemmas -situations in which two conflicting obligations are present in the same normative system. Such situations, when formalized (in SDL -standard deontic logic -or in other related logic), lead to inconsistency. Our proposal is based on preference relations that generate a tool of choice between the two conflicting normative solutions, which avoids the inconsistency and allows the full implementation of the system. Philosophical justifications are given for the logical tools as well as for their implications.

In this review I briefly analyse the main elements of each chapter of the book centred in the general areas of logic, epistemology, philosophy and history of science. Most of them are developed around a fine-grained investigation on the principle of non-contradiction and the concept of consistency, inquired mainly into the broad area of paraconsistent logics. The book itself is the result of a work that was initiated on the Studia Logica conference "Trends in Logic XVI: Consistency, Contradiction, Paraconsistency and Reasoning-40 years of CLE", held at the

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