ABSTRACT We critically review two extant paradigms for understanding the systematic interaction between modality and tense, as well as their respective modifications designed to do justice to the contingency of time’s structure and composition. We show that on either type of theory, as well as their respective modifications, some principles prove logically valid whose truth might sensibly be questioned on metaphysical grounds. These considerations lead us to devise a more general logical framework that allows accommodation of those metaphysical views that (...) its predecessors rule out by fiat. (shrink)

In order to explore public views on nanobiotechnology (NBT), convergence seminars were held in four places in Europe; namely in Visby (Sweden), Sheffield (UK), Lublin (Poland), and Porto (Portugal). A convergence seminar is a new form of public participatory activity that can be used to deal systematically with the uncertainty associated for instance with the development of an emerging technology like nanobiotechnology. In its first phase, the participants are divided into three “scenario groups” that discuss different future scenarios. In the (...) second phase, the participants are regrouped into three “convergence groups”, each of which contains representatives from each of the three groups from the first phase. In the final third phase, all participants meet for a summary discussion. This pilot project had two aims: (1) to develop and assess the new methodology and (2) to gather advice and recommendations from the public that may be useful for future decisions on nanobiotechnology (NBT). Participants emphasized that they wanted the technology to focus on solutions to environmental and medical problems and to meet the needs of developing countries. The need for further public participation and deliberation on NBT issues seemed to be acknowledged by all participants. Many of them also raised equality concerns. Views on the means by which NBT should be steered into socially useful directions were more divided. In particular, different views were expressed on how much regulation of company activities is needed to curb unwanted developments. The participants’ responses in a questionnaire indicate that the methodology of the convergence seminars was successful for decision-making under uncertainty. In particular, the participants stated that their advice was influenced both by access to different possible future developments and by the points of view of their co-participants, which is what the method is specifically intended to achieve. (shrink)

The outcome set of a belief change operator is the set of outcomes that can be obtained with it. Axiomatic characterizations are reported for the outcome sets of the standard AGM contraction operators and eight types of base-generated contraction. These results throw new light on the properties of some of these operators.

Generalizations of partial meet contraction are introduced that start out from the observation that only some of the logically closed subsets of the original belief set are at all viable as contraction outcomes. Belief contraction should proceed by selection among these viable options. Several contraction operators that are based on such selection mechanisms are introduced and then axiomatically characterized. These constructions are more general than the belief base approach. It is shown that partial meet contraction is exactly characterized by adding (...) to one of these constructions the condition that all logically closed subsets of the belief set can be obtained as the outcome of a single (multiple) contraction. Examples are provided showing the counter-intuitive consequences of that condition, thus confirming the credibility of the proposed generalization of the AGM framework. (shrink)

Two recent defences of the recovery postulate for contraction of belief sets are analyzed. It is concluded that recovery is defensible as a by-product of a formalization that is idealized in the sense of being simplified for the sake of clarity. However, recovery does not seem to be a required feature of the doxastic behaviour of ideal (perfectly rational) agents. It is reasonable to expect that there should be epistemic residues (remnants of rejected beliefs), but not that these should always (...) suffice to recover all the original beliefs if the discarded belief is reinstated. (shrink)

Eleven organic and two conventionalSwedish livestock farmers and two initiators(non-farmers who took part in shaping earlyorganic livestock production in Sweden) wereinterviewed, using a semi-structured method.Respondents were selected through purposive andheterogeneous sampling with regard toconversion year, type of production, and sizeof farm. Conversion of the animal husbandrytook place between 1974 and 2000. All but twohad positive attitudes towards organiclivestock production and saw it as a wayforward for Swedish livestock production,although especially the latecomers did notperceive it as the only alternative. There wasa (...) distinct difference in values between thepioneers, who converted their farms early, andthose converting later. Pioneer farmers sharedthe values of the initiators. They expressed amore ecocentric view emphasizing a systemicapproach, and displayed a more holisticapproach to questions, interpreting them inlarger frameworks. They also had a moreecocentric understanding of animal welfare. Thelater the conversion, the more important theeconomic reason for conversion appeared to be.Those converting later also tended to have amore superficial relationship to organicprinciples. However, the farmers also tended tobe more influenced by organic values the longerthey worked with organic farming. (shrink)

The basic assumption of repertoire contraction is that only some of the logically closed subsets of the original belief set are viable as contraction outcomes. Contraction takes the form of choosing directly among these viable outcomes, rather than among cognitively more far-fetched objects such as possible worlds or maximal consistent subsets of the original belief set. In this first investigation of repertoire contraction, postulates for various variants of the operation are introduced. Necessary and sufficient conditions are given for when repertoire (...) contraction coincides with AGM contraction or with operations generated by AGM-style contraction on a belief base. A close connection is shown to hold between repertoire contraction and specified meet contraction. (shrink)

EKONOMEN: Nej, det vi alla borde enas om är i stället att göra en rationell avvägning mellan olika samhällsmål. Vi har i själva verket genomfört flera mycket avancerade forskningsprojekt inom det nya området contingent valuation of violence, CVV. På grundval av noggranna analyser har vi t ex konstaterat att en våldtäkt bör värderas som en kostnad av 1237000 kronor, räknat i penningvärdet den 1 juli 2001.

Inom hakparentes anges den ordagranna betydelsen, när denna skiljer sig mycket från frasens gängse filosofiska innebörd. På tre- och fler-staviga ord har har ett accenttecken satts in före den betonade vokalen. (Tvåstaviga latinska ord har alltid betoningen på första stavelsen.).

Se resumen las ventajas y desventajas de la formalización en filosofía. Se concluye que la filosofía formalizada es una especialidad en peligro que necesita ser revitalizada, y que debe incrementar sus interacciones con la filosofía no formalizada. El estilo enigmático, que es común en la lógica filosófica, debe llevar a discusiones explícitas sobre la relación problemática entre modelos formales, conceptos filosóficos y temas que motiven su desarrollo.

In his paper ‘Changing the Theory of Theory Change: Reply to My Critics’, N. Tennant (1997b) reacts to the critical reception of an earlier article of his. The present note rectifies some of the most serious misrepresentations in Tennant's reply.

In his paper 'Changing the Theory of Theory Change: Reply to My Critics', N. Tennant (1997b) reacts to the critical reception of an earlier article of his. The present note rectifies some of the most serious misrepresentations in Tennant's reply.

This is a response to an article by Wade Allison in which he argues that we should accept drastically higher doses of ionizing radiation than what we currently do. He employs four arguments in defence of his position: comparisons with background radiation, the positive experiences of radiotherapy, the presence of biological defence mechanisms against radiation, and a concession by Swedish authorities that their approach to reindeer meat after the Chernobyl fallout was unnecessarily strict. It is shown that each of the (...) four arguments is fallacious. In conclusion, the traditional weighing of risks against benefits in radiation protection is defended. (shrink)

In the middle of the 1980s, logical tools were discovered that make it possible to model changes in belief and knowledge in entirely new ways. These logical tools turned out to be applicable both to human beliefs and to the contents of databases. This is the first textbook in this new area. It contains both discursive chapters with a minimum of formalism and formal chapters in which proofs and proof methods are presented. By using different selections from the formal section (...) the book can be used on all levels of University education. (shrink)

Proponents of situated affectivity hold that “tools for feeling” are just as characteristic of the human condition as are “tools for thinking” or tools for carpentry. An agent’s affective life, they argue, is dependent upon both physical characteristics of the agent and the agent’s reciprocal relationship to an appropriately structured natural, technological, or social environment. One important achievement has been the distinction between two fundamentally different ways in which affectivity might be intertwined with the environment: the “user-resource-model” and the “mind-invasion-model.” (...) The twofold purpose of this paper is to complement the debate about situated affectivity in general and about “mind invasion” in particular by, firstly, connecting it to situationist research in social psychology and, secondly, broadening the perspective to not only accommodate decidedly detrimental “invasions” but also potentially beneficial forms of “mind shaping” that include the manipulation of an agent’s experiential life and behaviour through the moulding of both the agent’s environment and the agent’s body. (shrink)

I explain the New Riddle of Induction (Goodman 1946, 1955) in very brief words.