Sven Ove Hansson

Theoria , the international Swedish philosophy journal, was founded in 1935. Its contributors in the first 75 years include the major Swedish philosophers from this period and in addition a long list of international philosophers, including A. J. Ayer, C. D. Broad, Ernst Cassirer, Hector Neri Castañeda, Arthur C. Danto, Donald Davidson, Nelson Goodman, R. M. Hare, Carl G. Hempel, Jaakko Hintikka, Saul Kripke, Henry E. Kyburg, Keith Lehrer, Isaac Levi, David Lewis, Gerald MacCallum, Richard Montague, Otto Neurath, Arthur N. Prior, W. V. Quine, Nicholas Rescher, Ernest Sosa, Robert C. Stalnaker, P. F. Strawson, Patrick Suppes, Johan van Benthem, Georg Henrik von Wright and many others. Hempel's confirmation paradoxes, Ross's deontic paradox, Montague's universal grammar and Lindström's theorem are among the contributions to philosophy that were first published in Theoria.

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.

Safety is a concern in almost all branches of engineering. Whereas safety was traditionally introduced by applying safety factors or margins to the calculated maximum load, this approach is increasingly replaced with probabilistic risk assessment (PRA) as a tool for dimensioning safety measures. In this paper, the two approaches are compared in terms of what they aim at and what they can, in fact, achieve. The outcome of this comparison suggests that the two approaches should be seen as complementary rather than mutually exclusive. PRA is particularly useful for priority setting and for the effect evaluation of safety measures; however, in most applications, uncertainties prevent PRA from providing an objective probability of failure or value of damage. Safety factors are indispensible for dealing with dangers that cannot be assigned meaningful probabilities.

The 1985 paper by Carlos Alchourrón, Peter Gärdenfors, and David Makinson, “On the Logic of Theory Change: Partial Meet Contraction and Revision Functions” was the starting-point of a large and rapidly growing literature that employs formal models in the investigation of changes in belief states and databases. In this review, the first twenty-five years of this development are summarized. The topics covered include equivalent characterizations of AGM operations, extended representations of the belief states, change operators not included in the original framework, iterated change, applications of the model, its connections with other formal frameworks, computatibility of AGM operations, and criticism of the model.