In this paper we study some questions concerning Łukasiewicz implication algebras. In particular, we show that every subquasivariety of Łukasiewicz implication algebras is, in fact, a variety. We also derive some characterizations of congruence permutable algebras. The starting point for these results is a representation of finite Łukasiewicz implication algebras as upwardly-closed subsets in direct products of MV-chains.

In this paper we study some questions concerning Łukasiewicz implication algebras. In particular, we show that every subquasivariety of Łukasiewicz implication algebras is, in fact, a variety. We also derive some characterizations of congruence permutable algebras. The starting point for these results is a representation of finite Łukasiewicz implication algebras as upwardly-closed subsets in direct products of MV-chains.

En este trabajo se describe un nuevo dispositivo didáctico que estamos diseñando y completando, los Recorridos de Estudio e Investigación (REI), que quieren contribuir a crear secuencias de enseñanza-aprendizaje.

This (by no means exhaustive) survey of Postman’s work reflects on his penetrating analyses of contemporary technology. He focused attention on the ways technology today, especially the television and the computer, inevitably change us. The essential questions he asks us to ask (and answer) are, How does technology affect us? Is it for good or ill? and Must we accept all technological advances? Postman recognized the current dominance and autonomy of technology as well as the concomitant dangers and consequently made (...) the case and the plea for the reassertion of human over technological values. (shrink)

Professor Hospers has produced a most competent text-book, with ‘selected readings’ and ‘exercises’ added to each chapter. He has in mind in the first place undergraduates in American universities; but anyone who wishes to familiarize himself with the methods and approaches to philosophy current in universities in England and the United States will find in this book a useful guide. Philosophy is seen as a critical and purgative activity. It is assumed that if we become clear about the logic of (...) our language a great many of the traditional problems of philosophy disappear or look very different. At least one is inclined to suppose that this is Professor Hospers’s assumption, though he is on the whole a little cagey about showing his own hand; and it may be significant that the name of Wittgenstein does not occur in the Index and that there is no discussion of Professor Ryle’s Concept of Mind—in particular, one is surprised to find no extended discussion of dispositional concepts. The section dealing with ‘the mental and the physical’, admirable though it is, has thus a somewhat old-fashioned appearance. (shrink)

The translators have sought an expression generally intelligible to philosophers, rather than one steeped in the phenomenological and existential tradition. This avoids jargon, but sacrifices coin which is becoming current. Locutions which seem peculiar to one oriented within the more restricted viewpoint can generally be justified. The English is often colloquial and imaginative, but sometimes agonized. The great loss is the blind alleys in the English where, in the original, the possibilities of further penetration are limitless. Some terms are misleading. (...) The book includes a valuable glossary of German expressions, copious notes, and an extensive index of English expressions.--J. M. (shrink)

Although Machiavelli was never a military commander, he was throughout much of his life deeply concerned with the conduct of martial affairs; in short, a Renaissance Herman Kahn. This book is an essay on the technique of war: how on army is organized, who make the best soldiers, field manœuvers and battle formations, logistics, internal stability and control of military units, techniques of siege; these are considered both historically with reference to the ancients, as well as the present—the contemporary applications (...) of these techniques in the author's own time. The editor has provided a long critical and historical introduction—amounting to a small monograph in itself—which helps to place Machiavelli's ideas in the tradition of military-political theorists of Western Europe.—P. J. M. (shrink)