Should Philosophers Take Lessons from Quantum Theory?

This essay examines some of the arguments in David Deutsch's book The Fabric of Reality , chief among them its case for the so-called many-universe interpretation of quantum mechanics (QM), presented as the only physically and logically consistent solution to the QM paradoxes of wave/particle dualism, remote simultaneous interaction, the observer-induced 'collapse of the wave-packet', etc. The hypothesis assumes that all possible outcomes are realized in every such momentary 'collapse', since the observer splits off into so many parallel, coexisting, but epistemically non-interaccessible 'worlds' whose subsequent branchings constitute the lifeline-or experiential world-series- for each of those proliferating centres of consciousness. Although Deutsch concedes that his 'multiverse' theory is counter-intuitive, he none the less takes it to be borne out beyond question by the sheer observational/predictive success of QM and the conceptual dilemmas that supposedly arise with alternative (single-universe) accounts. Moreover, he claims the theory resolves a range of longstanding philosophical problems, notably those of mind/body dualism, the various traditional paradoxes of time, and the freewill/determinism issue. The essay suggests on the contrary, that Deutsch unwittingly transposes into the framework of presentday quantum debate speculative themes from the history of rationalist metaphysics, often with bizarre or philosophically dubious results, and that he rules out at least one promising rival account, namely Bohm's 'hidden variables' theory. It goes on to consider reasons for resistance to that theory among proponents of the 'orthodox' (Copenhagen) doctrine, and for the strong anti-realist, at times even irrationalist bias that has characterized much of this discussion since Bohr's debates with Einstein about quantum non-locality, observer-intervention, and the limits of precise measurement. Finally, the contrast is pointed out between Deutsch's ontologically extravagant use of the many-worlds hypothesis (akin to certain ideas advanced by speculative metaphysicians from Leibniz down) and those realist modes of counterfactual reasoning- e.g. in Kripke and the early Putnam- which deploy similar arguments to very different causal-explanatory ends.     

Effects of informative peripheral cues on eye movements: Revisiting William James’ “derived attention”

Two experiments examined effects of peripheral information on the latency of saccadic eye movements. In Experiment 1, simple target stimuli were presented to the left or right visual field. Prior to each target, a pair of cue letters was presented for 40msec bilaterally. The relative location of the letters (W-S or S-W) was related to target location, but participants were not informed of this contingency. After a brief practice period, saccadic latencies were faster for targets at the likely location, as indicated by the letter pair. This derived peripheral cueing effect was related to participants' awareness of the relation between cue type and target location. Experiments 2A and 2B employed monocular viewing in order to compare performance across the nasal and temporal visual fields. The effect observed in Experiment 1 was confined to the nasal visual field. In a reflexive orienting condition, the effect of a unilateral letter cue was larger in the temporal visual field. It is concluded that the neurocognitive processes responsible for derived peripheral cueing are distinct from those involved in either reflexive or voluntary orienting.     

Predicting employee turnover from performance,satisfaction, and leader-member exchange

As part of a study of the role of supervision in, predicting turnover, 105 nurses provided confidential data on leader-member exchange and satisfaction with supervision, while their supervisors provided performance evaluation information. Although results reaffirmed an inverse correlation between employee performance and turnover (r=–.23p<.05), only directional support was obtained for the hypothesis that performance moderates the relationship between satisfaction with supervision and turnover. Turnover was also not found to be curvilinearly related to performance. Additionally, the, results did not replicate an earlier finding that leader-member exchange is a strong predictor of empolyee turnover. The results are interpreted as underscoring the difficulty of predicting turnover from affect, and the need to, develop refined theoretical models that specifically link these constructs.     

Differential social support and life change as contributors to the social class-distress relationship in older adults

Four hypotheses previously put forth to explain the strong association between social class and mental health in the general population were examined in 1,326 older adults (55 years and older). Respondents were interviewed 3 times at 6-month intervals. Lower class was associated with more past life changes (occurring before Wave 1) and more subsequent life events (occurring between Waves 1 and 3); these changes were predictive of distress, supporting the differential exposure hypothesis. Lower class was associated with weaker social support (embeddedness), which was related to distress, supporting the resource deterrent hypothesis. There was little evidence that people of the lower classes were more vulnerable to stress or that their status was due to their weaker social support; thus, the differential vulnerability and applied buffering hypotheses were not consistently supported. Social support does appear to be a versatile resource for older adults. A significant portion of the class-distress relationship was not accounted for by life change, social support, or the interaction between these factors.     

Adult generativity and the socialization of adolescents: relations to mothers' and fathers' parenting beliefs, styles, and practices

Mothers, fathers, and their adolescent children participated in two studies investigating the relations between Erikson's concept of generativityin adulthood and patterns of parenting. Study 1 involved 77 mothers and 48 fathers of 1st-year university students; Study 2 was part of an investigation of socialization processes in 35 families with an adolescent, aged 14-18. Parental generative concern was assessed by the Loyola Generativity Scale (LGS) of McAdams and de St. Aubin (1992) in each study. In both studies, mothers demonstrated positive relations between scores on the LGS and an authoritative style of parenting, as well as between generativity and more positive, optimistic views of adolescent development. In Study 2, these more positive views in turn mediated some aspects of autonomy-fostering practices used with the adolescent. Variations in fathers' levels of generative concern were less consistently related to these indices of parenting, however.     

The Bayesian reader: explaining word recognition as an optimal Bayesian decision process

This article presents a theory of visual word recognition that assumes that, in the tasks of word identification, lexical decision, and semantic categorization, human readers behave as optimal Bayesian decision makers. This leads to the development of a computational model of word recognition, the Bayesian reader. The Bayesian reader successfully simulates some of the most significant data on human reading. The model accounts for the nature of the function relating word frequency to reaction time and identification threshold, the effects of neighborhood density and its interaction with frequency, and the variation in the pattern of neighborhood density effects seen in different experimental tasks. Both the general behavior of the model and the way the model predicts different patterns of results in different tasks follow entirely from the assumption that human readers approximate optimal Bayesian decision makers.     

Detecting the malingering of cognitive deficits: An update

There has recently been a dramatic increase of empirical studies that investigate methods for detecting malingering of cognitive deficits. The present review focuses on a comparison of simulated and suspected malingerers in the malingering literature, and critiques the numerous approaches to the detection of malingering. The approaches that are reviewed include detection of floor effects, discrepancies of information, response bias, neuropsychological tests and batteries, symptom validity testing, and anomalous performance on memory tests. The latter approach has only recently been proposed by researchers and may show the most promise.