We prove that compactness is equivalent to the amalgamation property, provided the occurrence number of the logic is smaller than the first uncountable measurable cardinal. We also relate compactness to the existence of certain regular ultrafilters related to the logic and develop a general theory of compactness and its consequences. We also prove some combinatorial results of independent interest.

The classical Feferman–Vaught Theorem for First Order Logic explains how to compute the truth value of a first order sentence in a generalized product of first order structures by reducing this computation to the computation of truth values of other first order sentences in the factors and evaluation of a monadic second order sentence in the index structure. This technique was later extended by Läuchli, Shelah and Gurevich to monadic second order logic. The technique has wide applications in decidability and (...) definability theory. Here we give a unified presentation, including some new results, of how to use the Feferman–Vaught Theorem, and some new variations thereof, algorithmically in the case of Monadic Second Order Logic MSOL . We then extend the technique to graph polynomials where the range of the summation of the monomials is definable in MSOL . Here the Feferman–Vaught Theorem for these polynomials generalizes well known splitting theorems for graph polynomials. Again, these can be used algorithmically. Finally, we discuss extensions of MSOL for which the Feferman–Vaught Theorem holds as well. (shrink)

We investigate the expressive power of second-order logic over finite structures, when two limitations are imposed. Let SAA ) be the set of second-order formulas such that the arity of the relation variables is bounded by k and the number of alternations of second-order quantification is bounded by n . We show that this imposes a proper hierarchy on second-order logic, i.e. for every k , n there are problems not definable in AA but definable in AA for some c (...) 1 , d 1 . The method to show this is to introduce the set AUTOSAT of formulas in F which satisfy themselves. We study the complexity of this set for various fragments of second-order loeic. For first-order logic FOL with unbounded alternation of quantifiers AUTOSAT is PSpace complete. For first-order logic FOL n with alternation of quantifiers bounded by n , AUTOSAT is definable in AA . AUTOSAT) is definable in AA for some c 1 , d 1. (shrink)

Graph polynomials are graph parameters invariant under graph isomorphisms which take values in a polynomial ring with a fixed finite number of indeterminates. We study graph polynomials from a model theoretic point of view. In this paper we distinguish between the graph theoretic (semantic) and the algebraic (syntactic) meaning of graph polynomials. Graph polynomials appear in the literature either as generating functions, as generalized chromatic polynomials, or as polynomials derived via determinants of adjacency or Laplacian matrices. We show that these (...) forms are mutually incomparable, and propose a unified framework based on definability in Second Order Logic. We show that this comprises virtually all examples of graph polynomials with a fixed finite set of indeterminates. Finally we show that the location of zeros and stability of graph polynomials is not a semantic property. The paper emphasizes a model theoretic view. It gives a unified exposition of classical results in algebraic combinatorics together with new and some of our previously obtained results scattered in the graph theoretic literature. (shrink)

We show that the spectrum of a sentence ϕ in Counting Monadic Second Order Logic (CMSOL) using one binary relation symbol and finitely many unary relation symbols, is ultimately periodic, provided all the models of ϕ are of clique width at most k, for some fixed k. We prove a similar statement for arbitrary finite relational vocabularies τ and a variant of clique width for τ-structures. This includes the cases where the models of ϕ are of tree width at most (...) k. For the case of bounded tree-width, the ultimate periodicity is even proved for Guarded Second Order Logic GSOL. We also generalize this result to many-sorted spectra, which can be viewed as an analogue of Parikh's Theorem on context-free languages, and its analogues for context-free graph grammars due to Habel and Courcelle. Our work was inspired by Gurevich and Shelah (2003), who showed ultimate periodicity of the spectrum for sentences of Monadic Second Order Logic where only finitely many unary predicates and one unary function are allowed. This restriction implies that the models are all of tree width at most 2, and hence it follows from our result. (shrink)

We study the effects of Vopěnka's principle on properties of model theoretic logics. We show that Vopěnka's principle is equivalent to the assumption that every finitely generated logic has a compact cardinal. We show also that it is equivalent to the assumption that every such logic has a global Hanf number.

Finitary sketches, i.e., sketches with finite-limit and finite-colimit specifications, are proved to be as strong as geometric sketches, i.e., sketches with finite-limit and arbitrary colimit specifications. Categories sketchable by such sketches are fully characterized in the infinitary first-order logic: they are axiomatizable by σ-coherent theories, i.e., basic theories using finite conjunctions, countable disjunctions, and finite quantifications. The latter result is absolute; the equivalence of geometric and finitary sketches requires (in fact, is equivalent to) the non-existence of measurable cardinals.

Global Media Ethics is the first comprehensive cross-cultural exploration of the conceptual and practical issues facing media ethics in a global world. A team of leading journalism experts investigate the impact of major global trends on responsible journalism. The first full-length, truly global textbook on media ethics; Explores how current global changes in media promote and inhibit responsible journalism; Includes relevant and timely ethical discussions based on major trends in journalism and global media; Questions existing frameworks in media ethics in (...) light of the impact of global media; Contributors are leading experts in global journalism and communication. (shrink)

In The Face of Emotions, which was Carroll Izard’s first major attempt at elaborating his differential emotions theory, he stated that the book “presents a theoretical framework for the study of emotions and their role in personality and interpersonal processes.” Yet, over the years, his contribution to personality theory has generally been overshadowed by the attention focused on his views on facial expressions and the structure of emotions. This article will begin with a brief overview of the DET perspective on (...) personality development. Then, it will examine how the DET framework can be used to organize recent findings from three lines of research on adult personality. It will conclude with suggestions for future research as well as some personal recollections. (shrink)

Much of the progress in the fields constituting cognitive science has been based upon the use of explicit information processing models, almost exclusively patterned after conventional serial computers. An extension of these ideas to massively parallel, connectionist models appears to offer a number of advantages. After a preliminary discussion, this paper introduces a general connectionist model and considers how it might be used in cognitive science. Among the issues addressed are: stability and noise‐sensitivity, distributed decision‐making, time and sequence problems, and (...) the representation of complex concepts. (shrink)

The purpose of this article is to highlight ways in which institutional policymakers tend to insufficiently conceptualise their role as ethics practitioners. We use the case of blood product recall notification as a means of raising questions about the way in which, as we have observed it, discourse for those who make institutional ethics policies is constrained by routine balancing of simplified principles to the exclusion of reflexive practices—those that turn ethics reasoning back on itself. The latter allows ethics practitioners (...) with comparatively little formal training to take ownership of traditional parameters, which define their discussions and ultimately ought to make them more insightful when doing ethics. Thus, in the midst of calls for more training to increase the competency of ethics committees, we suggest that an additional problem of how these lay ethicists conceive of their roles also needs to be addressed. (shrink)

The selection of wanted from unwanted messages requires discriminatory mechanisms of as great a complexity as those in normal perception, as is indicated by behavioral evidence. The results of neurophysiology experiments on selective attention are compatible with this supposition. This presents a difficulty for Filter theory. Another mechanism is proposed, which assumes the existence of a shifting reference standard, which takes up the level of the most important arriving signal. The way such importance is determined in the system is further (...) described. Neurophysiological evidence relative to this postulation is discussed. (shrink)

Establishment holds that thc psychological mechanism of inference is the ment psychological thcorizing. Moreover, given this conciliatory reading, transformation of mental representations, it follows that perception is in.

A simple transposition in the text would, I venture to suggest, remove one or two of the many difficulties of this obscure chapter.

v. 1. Nicomachean ethics. Politics. The Athenian Constitution. Rhetoric. On Poetics.--v. 2. Logic.--v. 3. Physics. Metaphysics. On the soul. Short physical treaties.--v. 4. On the heavens. On generation and corruption. Meteorology. Biological treatises.

Some philosophers hold that philosophy is what you do to a problem until it’s clear enough to solve it by doing science. Others hold that if a philosophical problem succumbs to empirical methods, that shows it wasn’t really philosophical to begin with. Either way, the facts seem clear enough: questions first mooted by philosophers are sometimes coopted by people who do experiments. This seems to be happening now to the question: “what are propositional attitudes?” and cognitive psychology is the science (...) of note. (shrink)

Im Jahrgang LXV der Recherches de Théologie et Philosophie médiévales wurde die Reihe «Entretiens» inauguriert, in der angesehene Forscher auf dem Gebiet der mittelalterlichen Theologie und Philosophie zu ihrem persönlichen Werdegang als Forscher, zu ihren Forschungsschwerpunkten und zur Zukunft der Mittelalterforschung Auskunft geben. Das zweite Interview führten Jan A. Aertsen und Andreas Speer mit Wolfgang Kluxen, emeritierter Ordinarius für Philosophie in Bonn, von 1972 bis 1982 Präsident, später président d’honneur der Société Internationale pour l’Étude de la Philosophie Médiévale.

Was Metaphysik ist, läßt sich nicht apriorisch bestimmen, sondern zeigt sich erst in den denkerischen Entwürfen eines Ersten und Grundlegenden. Metaphysik ist, wie Philosophie überhaupt, von ihrer Geschichte nicht trennbar. Die philosophische Bedeutung der Periode des Mittelalters für den Gang der abendländischen Metaphysik ist in den letzten Jahrzehnten durch zwei klassische Studien herausgestellt worden.