Harmonious logic: Craig’s interpolation theorem and its descendants

Though deceptively simple and plausible on the face of it, Craig’s interpolation theorem (published 50 years ago) has proved to be a central logical property that has been used to reveal a deep harmony between the syntax and semantics of first order logic. Craig’s theorem was generalized soon after by Lyndon, with application to the characterization of first order properties preserved under homomorphism. After retracing the early history, this article is mainly devoted to a survey of subsequent generalizations and applications, especially of many-sorted interpolation theorems. Attention is also paid tomethodological considerations, since the Craig theorem and its generalizations were initially obtained by proof-theoretic arguments while most of the applications are model-theoretic in nature. The article concludes with the role of the interpolation property in the quest for “reasonable” logics extending first-order logic within the framework of abstract model theory. For Bill Craig, with great appreciation for his fundamental contributions to our subject, and for his perennially open, welcoming attitude and fine personality that enhances every encounter.     

Democratic Answers to Complex Questions – An Epistemic Perspective

This paper addresses a problem for theories of epistemic democracy. In a decision on a complex issue which can be decomposed into several parts, a collective can use different voting procedures: Either its members vote on each sub-question and the answers that gain majority support are used as premises for the conclusion on the main issue (premise based-procedure, pbp), or the vote is conducted on the main issue itself (conclusion-based procedure, cbp). The two procedures can lead to different results. We investigate which of these procedures is better as a truth-tracker, assuming that there exists a true answer to be reached. On the basis of the Condorcet jury theorem, we show that the pbp is universally superior if the objective is to reach truth for the right reasons. If one instead is after truth for whatever reasons, right or wrong, there will be cases in which the cbp is more reliable, even though, for the most part, the pbp still is to be preferred.     

The Social Value of Non-Deferential Belief

We often prefer non-deferential belief to deferential belief. In the last twenty years, epistemology has seen a surge of sympathetic interest in testimony as a source of knowledge. We are urged to abandon ‘epistemic individualism’ and the ideal of the ‘autonomous knower’ in favour of ‘social epistemology’. In this connection, you might think that a preference for non-deferential belief is a manifestation of vicious individualism, egotism, or egoism. I shall call this the selfishness challenge to preferring non-deferential belief. The aim of this paper is to meet the selfishness challenge by arguing that non-deferential belief is (pro tanto) socially valuable.     

The influence of lawyers' questions on witness accuracy,confidence, and reaction times and on mock jurors' interpretation of witness accuracy

Two studies demonstrate the influence of lawyers' complex questions on mock‐witness accuracy, confidence, and reaction times and on the interpretation of witness accuracy by mock jurors. In study one, 32 mock witnesses were shown a short film and then questioned either with lawyers' complex questions or simple alternatives. In Study 2, 20 mock jurors viewed video footage of the mock witnesses assigned to each of the two previous conditions and were asked to rate their confidence in the witnesses' answers. The findings of the two studies indicated that lawyers' use of confusing questions reduce not only accuracy but also speed of response and both witnesses' and jurors' ability to determine accuracy. The implication of these findings is straightforward, lawyers should ask simple questions wherever possible. Copyright © 2010 John Wiley & Sons, Ltd.     

Alibi believability: Corroborator certainty,cooperativeness and relationship with the defendant

Alibi believability can be affected by characteristics of the alibi corroborator, including the relationship between the defendant and corroborator, which has been studied extensively by researchers. The corroborator's certainty that they were together at the time of the crime may also influence alibi believability, but only a few studies have examined this. Another factor that may affect believability is the corroborator's cooperativeness with the police, which is yet to be studied in the alibi context. Online U.S. participants recruited from CloudResearch (N = 280) acted as mock jurors and evaluated a mock arson case where the defendant used an alibi defence. The alibi corroborator's relationship to the defendant (brother/neighbour), the certainty that they were together at the time (65%/100%) and cooperativeness with police (cooperative/uncooperative) were manipulated between participants. The participants were evenly split when it came to verdict (p > .05) but were more likely to vote guilty when the corroborator was a brother rather than a neighbour (p < .01) and when the brother was uncooperative versus cooperative (p < .05). As expected, alibis were more believable when they were corroborated by a neighbour rather than a brother and when the corroborator was 100% certain that they were together versus 65% certain (ps < .01). Alibis were also more believable when the corroborator cooperated than when he was uncooperative (p < .01). Cooperative (vs. uncooperative) corroborators led to more positive defendant and corroborator views on all six character trait measures (ps < .01). Implications and future directions are discussed.     

“Instruction Publique” in the French Eighteenth-Century Discourse of Modernisation

Towards the end of eighteenth century in France, the newly acquired rights of people as citizens needed assuring. This article traces the principles through which Condorcet tried to realise this on an institutional level. Condorcet did not view the Enlightenment ideas of progress as primarily referring to the state. Rather, he focused on the rights of individuals, particularly on their right to develop their own potential. He bound this perception with the unconditional demand for recognition of the rights of all people, in particular also for a clear renunciation of any gender-specific interpretation of this fundamental idea. Evidence for this is found in Condorcets writings on Instruction Publique. In contrast to other educational programmes of the revolutionary period, these evince a discriminating interpretation of freedom and equality, and recognise the numerous threats to a self-determined human existence.     

In Search of Causes of Hung Juries

A major problem facing the jury system is the hung jury. Several solutions have been proposed i.e., to minimize the decision rule, to create mixed juries, or to give the jury the 'dynamite' instructions. Nevertheless, no efforts have been made to determine the underlying causes of a hung jury. This paper presents an empirical study of hung versus unanimous juries in terms of the deliberation style and content. It suggests ways of avoiding hung juries.     

近20年来美国法律社会心理学研究新进展

20世纪80年代以来美国法律社会心理学在陪审团、证人证言、公民对犯罪的态度等方面的研究取得了一些新成果。从这些新成果可以看出,该领域的研究者们更注重将社会心理学与法学的观点和研究视角相结合,使自己的理论成果更符合实践要求。