It is shown that both classical and intuitionistic propositional logics of an associative binary modality are undecidable. The proof is based on the deduction theorem for these logics.

From the book: What is to be done with political ecology? Nothing. What is to be done? Political ecology!

It is shown that the expressive power of second-order propositional modal logic whose modalities are S4.2 or weaker is the same as that of second-order predicate logic.

We motivate and formalize the idea of sameness by default: two objects are considered the same if they cannot be proved to be different. This idea turns out to be useful for a number of widely different applications, including natural language processing, reasoning with incomplete information, and even philosophical paradoxes. We consider two formalizations of this notion, both of which are based on Reiter’s Default Logic. The first formalization is a new relation of indistinguishability that is introduced by default. We (...) prove that the corresponding default theory has a unique extension, in which every two objects are indistinguishable if and only if their non-equality cannot be proved from the known facts. We show that the indistinguishability relation has some desirable properties: it is reflexive, symmetric, and, while not transitive, it has a transitive “flavor.” The second formalization is an extension (modification) of the ordinary language equality by a similar default: two objects are equal if and only if their non-equality cannot be proved from the known facts. It appears to be less elegant from a formal point of view. In particular, it gives rise to multiple extensions. However, this extended equality is better suited for most of the applications discussed in this paper. (shrink)

Entscheidungen verweisen in einem begrifflichen Sinne auf Gründe. Entscheidungssysteme bieten eine probabilistische Verlässlichkeit als Rechtfertigung von Empfehlungen an. Doch nicht für alle Situationen mögen Verlässlichkeitsgründe auch angemessene Gründe sein. Damit eröffnet sich die Idee, die Güte von Gründen von ihrer Angemessenheit zu unterscheiden. Der Aufsatz betrachtet an einem Beispiel, einem KI-Lügendetektor, die Frage, ob eine (zumindest aktuell nicht gegebene) hohe Verlässlichkeit den Einsatz rechtfertigen kann. Gleicht er nicht einem Richter, der anhand einer Statistik Urteile fällen würde?

This book presents the proceedings of the 2nd Karl Schwarzschild Meeting on Gravitational Physics, focused on the general theme of black holes, gravity and information. Specialists in the field of black hole physics and rising young researchers present the latest findings on the broad topic of black holes, gravity, and information, highlighting its applications to astrophysics, cosmology, particle physics, and strongly correlated systems.

Persons infected with the Human Immunodeficiency Virus often experience intermittent life-threatening infections, a progressive decrease in cognitive abilities, and a loss of capacity to communicate their wishes to their family and medical care providers. Accordingly, AIDS patients are among those most likely to benefit from the increased availability of legally recognized forms of advance care planning. Although the three countries examined in this article differ greatly in the prevalence of HIV infection, the legal status of advance directives, and in the (...) attitudes toward their use, a collection of case studies is used to demonstrate that an ability to address the specific needs, values and goals of individual patients is promoted by the availability of a variety of options for implementing advance directives or health care proxies. The conclusion of the analysis is that the best option in a specific context will depend upon differences in individual values and medical objectives of the sort discussed in the case studies. Das mit der HIV-Infektion verbundene Krankheitsbild ist durch wechselnde lebensbedrohliche Infektionen und den fortschreitenden Verfall kognitiver Fähigkeiten gekennzeichnet. Es führt zudem häufig zum Verlust der Möglichkeit, Behandlungswünsche gegenüber Ärzten und Angehörigen zu äußern. Deshalb gehören besonders AIDS-Patienten zu denjenigen, die von rechtlich anerkannten vorsorglichen Patientenverfügungen profitieren werden.In diesem Artikel werden drei Länder betrachtet, die sich hinsichtlich der Häufigkeit des Auftretens der HIV-Infektion sowie des rechtlichen Status von und der Einstellung zu Patientenverfügungen erheblich unterscheiden. Fallstudien belegen allerdings, daß nicht allein die kulturellen und sozialen Bedingungen für die jeweils beste Form der Patientenverfügung ausschlaggebend sind. Voraussetzung für die Möglichkeit, den Bedingungen, Wert- und Zielvorstellungen des individuellen Patienten zu entsprechen, ist auf jeden Fall die Verfügbarkeit unterschiedlicher Formen von Patienten- und Betreuungsverfügungen. Auch innerhalb eines Kulturkreises müssen daher verschiedene Formen vorsorglicher Willensäußerungen des Patienten rechtlich anerkannt werden. Welche Art von Verfügung jeweils die beste Option darstellt, ist dabei abhängig von medizinischen Bedingungen und persönlichen Wertvorstellungen, wie sie in den Fallstudien diskutiert werden. (shrink)

Giordano Bruno's notorious public death in 1600, at the hands of the Inquisition in Rome, marked the transition from Renaissance philosophy to the Scientific Revolution of the seventeenth century. In his philosophical works he addressed such delicate issues as the role of Christ as mediator and the distinction, in human beings, between soul and matter. This volume presents new translations of Cause, Principle and Unity, in which he challenges Aristotelian accounts of causality and spells out the implications of Copernicanism (...) for a new theory of an infinite universe, and of two essays on magic, On Magic and A General Account of Bonding, in which he interprets earlier theories about magical events in the light of the unusual powers of natural phenomena. (shrink)

L'origine dell'anima umana secondo Dante.--La dottrina d'Alberto Magno sull'Inchoatio formae.--Alberto Magno e san Tommaso.--La posizione di Alberto Magno di fronte all'averroismo.--L'anima umana secondo Sigieri.--Anima e corpo nel pensiero di san Tommaso.--L'aristotelismo della scolastica e i francescani.--Individualità e immortalità nell'averroismo e nel tomismo.