ABSTRACT Nassim Taleb rightly points out that although people may acknowledge in the abstract that the world is uncertain, they still behave as if a large enough sample size is all that is needed to predict, and model, the future. He also rightly notes that ever?increasing quantities of information are relevant only in simple situations, such as in predicting the range of human height, but are misleading in more random arenas, such as financial markets. However, while Taleb decries the use (...) of narratives for falsely forcing the facts to fit a given story, we need narratives in order to make sense of a complex world. Further, Taleb fails to take sufficient heed of the fact that human narratives themselves become objects that act on subjects in an ever?increasing web of complexity. (shrink)

Deliberative democracy is unrealistic, but so are rational-choice models of democracy. The elements of reality that rationalistic theories of democracy leave out are the very elements that deliberative democrats would need to subtract if their theory were to be applied to reality. The key problem is not, however, the altruistic orientation that deliberative democrats require; opinion researchers know that voters are already sociotropic, not self-interested. Rather, as Schumpeter saw, the problems lie in understanding politics, government, and economics under modern—and postmodern—conditions. (...) Modernity entails levels of complexity that stymie voters' attempts to be well informed about which political promises will actually solve social problems. Postmodernity adds to complexity an overabundance of fragmented information experienced impatiently and fleetingly by citizens who confuse entertainment with knowledge, and whose political demands are as unrealistic as their personal desire for a unique identity. These factors can be added, one by one, to the minimalist rational-choice model of politics, with each step leading us farther away from deliberative democracy. (shrink)

Evidence Theory is a branch of mathematics that concerns combination of empirical evidence in an individual’s mind in order to construct a coherent picture of reality. Designed to deal with unexpected empirical evidence suggesting new possibilities, evidence theory is compatible with Shackle’s idea of decision-making as a creative act. This essay investigates this connection in detail, pointing to the usefulness of evidence theory to formalise and extend Shackle’s decision theory. In order to ease a proper framing of the issues involved, (...) evidence theory is compared with sub-additive probability theory and Ewens’s infinite alleles model. Furthermore, the original version of evidence theory is presented along with its most recent developments. (shrink)

A case is made for supposing that the total probability accounted for in a decision analysis is less than unity. This is done by constructing a measure on the set of all codes for computable functions in such a way that the measure of every effectively accountable subset is bounded by a number <1. The consistency of these measures with the Savage axioms for rational preference is established. Implications for applied decision theory are outlined.

Deliberative democracy is unrealistic, but so are rational-choice models of democracy. The elements of reality that rationalistic theories of democracy leave out are the very elements that deliberative democrats would need to subtract if their theory were to be applied to reality. The key problem is not, however, the altruistic orientation that deliberative democrats require; opinion researchers know that voters are already sociotropic, not self-interested. Rather, as Schumpeter saw, the problems lie in understanding politics, government, and economics under modern—and postmodern—conditions. (...) Modernity entails levels of complexity that stymie voters' attempts to be well informed about which political promises will actually solve social problems. Postmodernity adds to complexity an overabundance of fragmented information experienced impatiently and fleetingly by citizens who confuse entertainment with knowledge, and whose political demands are as unrealistic as their personal desire for a unique identity. These factors can be added, one by one, to the minimalist rational-choice model of politics, with each step leading us farther away from deliberative democracy. (shrink)

In this paper we analyse scientists' perspectives on the release of genetically modified crops into the environment, and the relationship between their perspectives and the context that they work within, e.g. their place of employment, funding of their research and their disciplinary background. We employed Q-methodology to examine these issues. Two distinct factors were identified by interviewing 62 scientists. These two factors included 92 per cent of the sample. Scientists in factor 1 had a moderately negative attitude to GM crops (...) and emphasised the uncertainty and ignorance involved, while scientists in factor 2 had a positive attitude to GM crops and emphasised that GM crops are useful and do not represent any unique risks compared to conventional crops. Funding had a significant effect on the perspective held by the scientists in this study. No ecologists were associated with factor 2, while all the scientists employed in the GM-industry were associated with this factor. The strong effects of training and funding might justify certain institutional changes concerning how we organise science and how we make public decisions when new technologies are to be evaluated. Policy makers should encourage more interdisciplinary training and research and they should make sure that representatives of different disciplines are involved in public decisions on new technologies. (shrink)