a doubtful law does not bind -- Second corollary : uncertain law cannot impose certain obligation -- Commentary on the Treatise on conscience.

The tree-based data structure of -tree for propositional formulas is introduced in an improved and optimised form. The -trees allow a compact representation for negation normal forms as well as for a number of reduction strategies in order to consider only those occurrences of literals which are relevant for the satisfiability of the input formula. These reduction strategies are divided into two subsets (meaning- and satisfiability-preserving transformations) and can be used to decrease the size of a negation normal form A (...) at (at most) quadratic cost. The reduction strategies are aimed at decreasing the number of required branchings and, therefore, these strategies allow to limit the size of the search space for the SAT problem. (shrink)

Como casi todos los conceptos fi losófi cos, el de «validez normativa» tiene altos grados de ambigüedad y de vaguedad. En este trabajo me encargo de analizar la postura de distintos autores que han tratado de dar respuesta a la pregunta ¿qué significa que una norma sea «válida»? Para ello, tomo como hilo conductor la obra de Ernesto Garzón Valdés. Esto se debe a que los trabajos de Ernesto Garzón dedicados a este tema, le ofrecen al lector un análisis crítico (...) y comprensivo de algunas de las posturas teóricas más relevantes sobre el concepto de validez normativa. Asimismo, trabajar a través de su obra tiene un doble benefi cio: por un lado, no sólo nos permite conocer a fondo la postura teórica de autores que pertenecen a distintas corrientes del pensamiento, como Hans Kelsen, H.L.A. Hart, Francisco Suárez o von Wright por ejemplo, sino que, por el otro, nos permite conocer la postura del mismo Garzón y sus críticas a los diferentes modelos conceptuales. (shrink)

Using a recent result of Busch and Gudder, we reconsider a theorem of Ludwig which allows one to identify a class of effect automorphisms as the symmetry transformations in quantum mechanics.

Semantic Automata Johan van Ben them. INTRODUCTION An attractive, but never very central idea in modern semantics has been to regard linguistic expressions ...

In this paper art history and visual studies, the disciplines that study visual culture, are presented as a field whose conjectural paradigm can be used to understand the epistemic problems associated with abduction. In order to do so, significant statements, concepts and arguments from the work of several specialists in this field have been highlighted. Their analysis shows the fruitfulness and potential for understanding the study of visual culture as a field that is interwoven with the assumptions of abductive cognition.