Stefan Schubert

Coherence Reasoning and Reliability: A Defense of the Shogenji Measure

A measure of coherence is said to be reliability conducive if and only if a higher degree of coherence (as measured) results in a higher likelihood that the witnesses are reliable. Recently, it has been proved that several coherence measures proposed in the literature are reliability conducive in a restricted scenario (Olsson and Schubert 2007, Synthese 157:297–308). My aim is to investigate which coherence measures turn out to be reliability conducive in the more general scenario where it is any finite number of witnesses that give equivalent reports. It is shown that only the so-called Shogenji measure is reliability conducive in this scenario. I take that to be an argument for the Shogenji measure being a fruitful explication of coherence.

Is coherence conducive to reliability

A measure of coherence is said to be reliability conducive if and only if a higher degree of coherence (as measured) of a set of testimonies implies a higher probability that the witnesses are reliable. Recently, it has been proved that the Shogenji measure of coherence is reliability conducive in restricted scenarios (e.g., Olsson and Schubert, Synthese, 157:297–308, 2007). In this article, I investigate whether the Shogenji measure, or any other coherence measure, is reliability conducive in general. An impossibility theorem is proved to the effect that this is not the case. I conclude that coherence is not reliability conducive.

Coherence and Reliability in Judicial Reasoning

Experimental studies of how juries reach their verdicts in court strongly suggest that coherence reasoning is ubiquitous in judicial reasoning. Under massive cognitive pressure to process large numbers of conflicting pieces of evidence and witness reports, jury members base their judgment on an assessment of the most coherent account of the events. From a normative perspective, the legitimacy of coherence reasoning in court hinges on the premise that such coherence is a plausible guide to justified belief. Unfortunately, this notion has been severely challenged by numerous recent studies in Bayesian formal epistemology. Bovens and Hartmann (2003) (Bayesian epistemology). New York/Oxford: Oxford University Press and Olsson (2005) (Against coherence: Truth, probability and justification). Oxford: Oxford University Press have shown that there is no way to measure coherence such that coherence is truth conducive in the sense that more coherence implies a higher likelihood of truth. This is so even under seemingly very weak boundary conditions. In previous work we have shown that (certain forms of) coherence can be reliability conducive in paradigmatic scenarios where such coherence fails to be truth conducive. In other words, more coherence can still be indicative of a higher probability that the witnesses are reliable. We have also argued that the connection between (certain forms of) coherence and probability of reliability may be what justifies our common reliance on coherence reasoning. While the link between coherence and reliability was found to be not completely general, our studies so far do support the contention that this link is stronger than that between coherence and truth. In this paper, we add credence to this conclusion by proving several new formal results connecting one prominent measure of coherence, the Shogenji measure, to witness reliability. The most striking of these results is that in a case where the witnesses’ degrees of reliability are maximally dependent of each other—i.e., where either all witnesses are reliable or all witnesses are unreliable—the Shogenji measure is reliability conducive. We also relate our approach to the Evidentiary Value tradition in Scandinavian legal theory.

The Macho Magister Ludi: An Analysis of Ernest Gellner's Thought-Style

Summary Ernest Gellner was, by all accounts, one of the most unconventional thinkers of the twentieth century. Not only was the content of his theories often strikingly original, but he also arrived at them by use of a singularly personal thought-style. The article describes the most salient features of this thought-style: his quest for overviews, on the one hand, and for penetrating and unexpected insights, on the other, his opposition to what he perceived as humanistic complacency, his academic elitism, and much else. In the final section, an assessment of the most conspicuous feature of Gellners thought-style—his tendency to downplay the importance of detail and to focus on high-level theory—is given. It is argued that this characteristic served Gellner better in philosophy and the history of ideas than in the social sciences.

Ernest Gellner’s Use of the Social Sciences in Philosophy

It is well known that Ernest Gellner made substantial use of his knowledge of the social sciences in philosophy. Here I discuss how he used it on the basis of a few examples taken from Gellner’s philosophical output. It is argued that he made a number of highly original “translations”, or re-interpretations, of philosophical theories and problems using his knowledge of the social sciences. While this method is endorsed, it is also argued that some of Gellner’s translations crossed the line between the original and the idiosyncratic.