Against global method safety

The global method safety account of knowledge states that an agent’s true belief that p is safe and qualifies as knowledge if and only if it is formed by method M, such that her beliefs in p and her beliefs in relevantly similar propositions formed by M in all nearby worlds are true. This paper argues that global method safety is too restrictive. First, the agent may not know relevantly similar propositions via M because the belief that p is the only possible outcome of M. Second, there are cases where there is a fine-grained belief that is unsafe and a relevantly similar coarse-grained belief (with looser truth conditions) that is safe and where both beliefs are based on the same method M. Third, the reliability of conditional reasoning, a basic belief-forming method, seems to be sensitive to fine-grained contents, as suggested by the wide variation in success rates for thematic versions of the Wason selection task.

     

Methods of correcting correlations for indirect restriction of range with non-interval data

A derivation is presented for correcting correlations for indirect restriction of range when correlations between one selection variable and non-interval measures are involved. Following a systematic investigation of special cases, formulas are given for practical application in validation work. Procedures for the case with several selection variables are briefly discussed.This study was initiated when the author was with the Institute of Military Psychology, Sweden.     

Belief contraction without recovery

The postulate of recovery is commonly regarded to be the intuitively least compelling of the six basic Gärdenfors postulates for belief contraction. We replace recovery by the seemingly much weaker postulate of core-retainment, which ensures that if x is excluded from K when p is contracted, then x plays some role for the fact that K implies p. Surprisingly enough, core-retainment together with four of the other Gärdenfors postulates implies recovery for logically closed belief sets. Reasonable contraction operators without recovery do not seem to be possible for such sets. Instead, however, they can be obtained for non-closed belief bases. Some results on partial meet contractions on belief bases are given, including an axiomatic characterization and a non-vacuous extension of the AGM closure condition.     

The effect of mirthfulness upon amount of discordant right-left occipital EEG alpha

A total of 68 subjects participated in two experiments that tested the effect of exposure to comedy upon amount of discordant right-left occipital EEG alpha. Data from both showed less discordant alpha in the laughers and more in the nonlaughers at the end of exposure to a filmed comedy, as contrasted by no such group difference before treatment. Experiment 2 clarified that the production of discordant alpha in the right hemisphere was significant to this group difference, that this effect was specific to comedy treatment (nondiscriminative effects of exposure to a neutral film), and that a reversed group difference in amount of discordant right hemisphere alpha occurred after instructed hypoventilation (nondiscriminative effect of hyperventilation; counterbalanced order of all four treatments). The results were discussed in relation to (a) recent findings on right-left hemisphere characteristics of depressed individuals, (b) the significance of motivational states, (c) a link between cerebral blood flow and EEG indicators of activation, (d) ventilatory effects upon cortical activation, (e) personality differences inherent in tolerance for CO₂-blood concentration, and (f) recent findings on corticothalamic connections.     

Coherentist Contraction

A model of coherentist belief contraction is constructed. The outcome of belief contraction is required to be one of the coherent subsets of the original belief set, and a set of plausible properties is proposed for this set of coherent subsets. The contraction operators obtained in this way are shown to coincide with well-known belief base operations. This connection between coherentist and foundationalist approaches to belief change has important implications for the philosophical interpretation of models of belief change.     

Detecting silent pauses in speech: a new tool for measuring on-line lexical and semantic processing

In this study, we introduce pause detection (PD) as a new tool for studying the on-line integration of lexical and semantic information during speech comprehension. When listeners were asked to detect 200-ms pauses inserted into the last words of spoken sentences, their detection latencies were influenced by the lexical-semantic information provided by the sentences. Listeners took longer to detect a pause when it was inserted within a word that had multiple potential endings, rather than a unique ending, in the context of the sentence. An event-related potential (ERP) variant of the PD procedure revealed brain correlates of pauses as early as 101 to 125 ms following pause onset and patterns of lexical-semantic integration that mirrored those obtained with PD within 160 ms of pause onset. Thus, both the behavioral and the electrophysiological responses to pauses suggest that lexical and semantic processes are highly interactive and that their integration occurs rapidly during speech comprehension.     

Welfare,Justice, and Pareto Efficiency

In economic analysis, it is usually assumed that each individuals well-being (mental welfare) depends on her or his own resources (material welfare). A typology is provided of the ways in which one persons well-being may depend on the material resources of other persons. When such dependencies are taken into account, standard Paretian analysis of welfare needs to be modified. Pareto efficiency on the level of material resources need not coincide with Pareto efficiency on the level of well-being. A change in economic conditions that is Pareto efficient in the standard sense, i.e., with respect to material resources, may nevertheless sacrifice one persons well-being to that of another. It is shown that under plausible assumptions, Pareto efficiency on the level of well-being may require the reduction of inequality on the level of material resources.