An interpretation of the “Parmenides” is proposed in base to the Plato’s “unwritten doctrines”. The greek author demonstrates in this dialogue that with the One only is impossible to think (hypothesis I), and this is why a principle of difference is required; that with the ontological conception of this difference neither, because contradictory conclusions would be followed (hypothesis II); and that without the One isimpossible to think, too (hypothesis III). These conclusions suggest the reader that the One is necessary to think, but another or other principles must be searched to stablish a dialectic. Plato confirms this way the parenetic character of his dialogues respecting at the same time the selfconstrained taboo of the “unwritten doctrines” (he doesn’t mention the undefinite dyad). To come to these conclusions the author ofthis paper proposes a plan of the second part of this work, that divides it in three hypothesis, not in eight, like is usual today, and analyzes the categories that sustain the argumentatives subdivisions of each one of the hypotheses: the structure of all the hypotheses is the same. All this in critical discussion with the actual bibliography about the topics.

This paper addresses first the appticability of the main notions included in the general notion meant item, meant partial situation (MPST), meant activity (MACT), and implicitly meant background situation (IMBST) -that of meant agent will be only mentioned in an aside-, plus the notion meaning activity (MNGACT). It will be shown that, when coupled to other notions, such as ‘ontological status’ of IMBST relative to the focussed (part of) current situation (FCST), as well as to the matching ‘ontological’ properties of the meant items above, they allow to set up unified and apparently successful methods to explore important and debated pragmatic issues. Then their usefulness for research in the domain traditionally accorded to speech-act theory is put to (a preliminary) test; and finally the general processual sketch of linguistic activity advanced in the last Sections of P.I is carefully gauged as to its prospects regarding actual implementation of more specific processual sketches of both emission and reception linguistic activities.

This paper analyses some aspects in Osiander’s (1498-1552) “Preface” to De Revolutionibus (1543) by Nicolaus Copernicus (1473-1453) and the “Preface Letter” also by Copernicus to the Pope Paul III (1468-1549). The reading is carried out from the intellectual framework where the works are written, taking as a reference De Disciplinis (1531) by Juan Luis Vives (1492-1538), whose pedagogical thought had great influence on the 16th century. This paper points at the coincidence of attitudes as to the function of Mathematics, and therefore, of Astronomy, for both a purely probabilistic assessment of theastronomical hypotheses, and the overcoming of the instrumentality of the calculations by means of their practical use. This last channel, promoted by a sceptic academicism which was already present in the first half of the 16th century, contributes to a better understanding of the reality of the progressive acceptation of a new structure of the world. Vives has very frequently been talked of as the clear antecedent of the great masters of thought of the modern culture, but his style and the dynamics of his thought -totally Humanist- are very different from those of Copernicus and Osiander, and thus, this paper aims to analyse his cultural context and his reflections about himself.

This article argues for an intermediate standpoint concerning the theory of truth which finds an equilibrium between realist an epistemic conceptions of truth. At the same time it is accepted that truth is a notion with an ultimate realist sense, but it is made clear that this intuitive sense does only have a non-trivial (i.e. non-“disquotational”), reading if the function of “truth” is seen from within the epistemic framework of our practices of belief-formation (i.e. of confirmation and revision). Following the realist line one can reconstruct the unconditional validity attributed to the intuitive concept of truth out of its internal relation with the concept of “reality”; this in turn makes clear that the epistemic strategy of extracting this uncoditionality from an emphatic concept of perfect, infallible knowledge is more than weak. This is because only preserving the decisive function of truth as a corrective, as a fallibilist reserve (incompatible therefore with any concept of “infallible” knowledge) one can see how truth relates to cognitive learning processes. On the other hand, the strategy of this paper shows thus how this is possible avoiding the bad alternative of metaphysical realism and relativism.

There are several areas in logic where the monotonicity of the consequence relation fails to hold. Roughly these are the traditional non-monotonic systems arising in Artificial Intelligence (such as defeasible logics, circumscription, defaults, ete), numerical non-monotonic systems (probabilistic systems, fuzzy logics, belief functions), resource logics (also called substructural logics such as relevance logic, linear logic, Lambek calculus), and the logic of theory change (also called belief revision, see Alchourron, Gärdenfors, Makinson [2224]). We are seeking a common axiomatic and semantical approach to the notion of consequence whieh can be specialised to any of the above areas. This paper introduces the notions of structured consequence relation, shift operators and structural connectives, and shows an intrinsic connection between the above areas.

Let’s agree in calling “classical demonstration” a deduction that enables us to know the rational necessity that something is the case and cannot be otherwise. I propose to take seriously actual instances of this notion, e.g. some mathematical proofs, and explore certain discoursive and epistemic implications of their existence. Then I will look at questions about characterizing, rigorizing and acknowledging this kind of conclusive proof. Finally, some remarks on the meaning of Provability Logic in this context will be made.

An information recovery problem is the problem of constructing a proposition containing the information dropped in going from a given premise to a given conclusion that folIows. The proposition(s) to beconstructed can be required to satisfy other conditions as well, e.g. being independent of the conclusion, or being “informationally unconnected” with the conclusion, or some other condition dictated by the context. This paper discusses various types of such problems, it presents techniques and principles useful in solving them, and it develops algorithmic methods for certain classes of such problems. The results are then applied to classical number theory, in particular, to questions concerning possible refinements of the 1931 Gödel Axiom Set, e.g. whether any of its axioms can be analyzed into “informational atoms”. Two propositions are “informationally unconnected” [with each other] if no informative (nontautological) consequence of one also follows from the other. A proposition is an “informational atom” if it is informative but no information can be dropped from it without rendering it uninformative (tautological). Presentation, employment, and investigation of these two new concepts are prominent features of this paper.