La pensée de Brentano a exercé une durable influence sur la Philosophie en Pologne surtout grâce à Casimir Twardowski, disciple de Brentano et lui-même fondateur d'une importante école philosophique, proche en son ésprit de la philosophie analytique. Twardowski tout en développant certaines idées de Brentano parvenait dans diverses questions aux solutions opposées à Celles de son maître. L'article cherche à préciser les résultats de cette continuation et de cette opposition dans l'oeuvre de Twardowski et de ses disciples tels que Łukasiewicz, Kotarbiński, Czeżowksi, e.a.

Our objective in this paper is to clearly highlight the linguistic status of the copulative verb, especially with regard to the copula verb to be, with an eye on tracingthe influences of Logic on its approach as a syntactic entity and also on emphasizing the details that led to an eclectic definition. This epistemological approach aims at placing an emphasis on the subject of the diachronic and interdisciplinary copulative verb, in order to observe the way in which the conclusions from the level of the logical approach were transferred to the one of the linguistic approach and also to avoid the misuse of a series of concepts that were established either in a different domain or in the same domain, but at a different level. The main emphasis falls on defining the linguistic predicate through the grammatical tense.

Due to the failure of the classical principles of bivalence and verifunctionality, the logic of experimental propositions relative to quantum systemscannot be interpreted in Boolean algebras. However, we cannot say neither that this logic is captured by orthomodular lattices, as claimed by many authors along the line of Birkhoff‘s and von Neumann‘s standard approach. For the alleged violation of distributivity is based on the possibility of combining statements relative to complementary contexts, which does not refer to any experience and, consequently, has no meaning. Indeed, quantum logic should be interpreted in partial, transitive Boolean algebras whose compatibility relation limits the application of the connectives within each of its Boolean sub-algebras, which refer to partial, classical descriptions. Moreover, this approach of quantum logic makes it possible to deal with composite systems, which was not possible to do within the standard approach, and then to deal with the fundamental notion of quantum entanglement. The latter notion can be represented by a series of axioms of the object language that restrict the set of experimental statements bearing on a composite system, while its close link to the notion of complementarity can be expressed in the metalanguage.

In this paper, we evaluate the project of resurgence of metaphysics based on the pecularity of the quantum domain, a project that is supported by some contemporary philosophers. Beyond the general arguments against scientific realism that are still applicable here, we show that this project is faced with the three following issues that, we believe, make it unrealizable: (a) the problem raised by the realistic interpretation of the wave function, as a description of a ‘concrete physical fact’ of the independent reality; (b) the lack of any experimental counterpart of the (non-local) hidden variables quantum theories, and, in some cases, their incompatibility with the quantum predictions; and (c) the fact that the key-properties of quantum phenomena, like their non-locality, essentially depend on the observables that are used for their description and cannot then be assigned to any ‘independent’ reality.

A dix ans d’intervalle deux déontciens de premier plan, G.H. von Wright et H.N. Castañeda, ont abordé -indépendamment l’un de l’autre- le probleme du fondement des normes et des énoncés normatifs. Leurs solutions respectives méritent d’être attentivement examinées. Ne prêtent-elles pas a discussion? Pour qu’une norme juridique soit fondée, suffit-il qu’elle soit édictée par un législateur compétent conformément a la procédure législative en vigueur? Un énoncé nornlatif est-il fondé du moment que l’ordre en faisant partie est légitimé au sens conféré a ce terme par l’auteur de Thinking and doing? Et tout d’abord peut-on admettre que les ordres fassent partie des énoncés nomlatifs? L’article qui suit essaie de répondre à ces questions et aux questions connexes.

In this paper everyday reasoning is examined fromm the standpoint of natural logic. In natural logic there is the supposition of the concept of schematisation, i.e. the discursive representation of a situation that a speaker A constructs for a listener B and that B must reconstruct for himself.Under these circumstances, in order to prove that a statement s is true A must present it in such a way that B does not call it into question, that he considers it a fact. For this it is necessary to have proofs. Moreover, a fact is never isolated and it may therefore appear inconsistent with other facts. A is thus led to provide reasons in order to substantiate his statements.Some mechanisms of proofs and of reasons are investigated.