Pleonastic possible worlds

The role of possible worlds in philosophy is hard to overestimate. Nevertheless, their nature and existence is very controversial. This is particularly serious, since their standard applications depend on there being sufficiently many of them. The paper develops an account of possible worlds on which it is particularly easy to believe in their existence: an account of possible worlds as pleonastic entities. Pleonastic entities are entities whose existence can be validly inferred from statements that neither refer to nor quantify over them as a matter of conceptual necessity. Definitions are proposed that ensure that this is the case for possible worlds.     

Predictors of Smoking Status After Eight Years: The Interaction of Stages of Change and Addiction Variables

Abstract

With a smoking rate of 30% of the population Switzerland has one of the highest rates of all industrialised countries. Changes in smoking status over eight years are examined by analysing the course of non-smokers, former smokers and current smokers between 1987 and 1995. Stages of change and addiction variables, as well as their interaction, are analysed for 1987 as predictors of smoking status in 1995.A sample of 953 non-smokers and former and current smokers was interviewed in 1987 and followed up in 1995. Between 1987 and 1995 every fifth non-smoker (20.9%) began smoking. The higher one is in the stage hierarchy the higher the probability of forward than of backward movement. Within the stages of change the likelihood of cessation is moderated by addiction variables. Thus, in the case of contemplating smokers in 1987, the more cigarettes they smoked daily at that time the less likely they were to be former smokers by 1995, but for preparating smokers who had already made an attempt to quit the converse holds - the more they smoked in 1987, the more likely they were to be non-smokers eight years later. The same holds for former smokers in 1987: former moderate smokers then were more likely to relapse than former heavy smokers. The implications for prevention and intervention are discussed.     

Structural Equation Modeling of Spatial Presence: The Influence of Cognitive Processes and Traits

This article examines the formation process of spatial presence, which is conceived as a two-step process involving the construction of a mental model of the mediated environment, followed by the emergence of spatial presence. During both stages, cognitive processes and user traits are in effect. We present data derived from a pooled set of data of three studies using the same virtual environment. Structural equation modeling is used to confirm the proposed theoretical model. The results show that attention and the trait of visual spatial imagery are positive predictors of the mental model of the mediated environment. In the second step, the formation of spatial presence is governed by involvement, the suspension of disbelief, and the domain-specific interest, together with the mental model.     

Navigating Social Roles in Pursuit of Important Goals: A Communal Goal Congruity Account of STEM Pursuits

Our exploration of communal goal processes in decisions about science, technology, engineering, and mathematics (STEM) careers integrates research on goal pursuit processes with research on stereotyping and on social role occupancy. Social roles encompass expectations and resources that can originate from group membership in broad social categories, such as gender, ethnicity, or nationality, or from more narrowly focused occupational and family roles. Our review elaborates on three ways in which social roles intersect with goal pursuit processes, with particular attention to how communal goals influence STEM pursuits. First, social roles influence goal selection or what goals are prioritized generally and at a particular time. Second, beliefs about social roles can influence the kinds of roles that people shy away from or seek out. Third, occupying a particular social role can actually facilitate or impede goal progress. With regard to STEM pursuits, we demonstrate that communal goals are valued both generally by people and especially by women, and that consensual stereotypes describe STEM fields as less likely to afford communal goals than other occupational roles. However, emphasizing the communal aspects of STEM fields elicits greater positivity toward these roles. Finally, we explore the ways in which STEM occupational roles are or might be enacted in communally‐oriented ways. The goal congruity perspective thus can offer a unifying framework to integrate an understanding of the social structure – that is, roles and contexts – with the social cognition of the individual – that is, critical motivational and cognitive processes.     

Influence of a depressant drug on acquisition in rote learning

Central depressant drugs have been shown to impair performance during learning and at recall. The experiment which is described was carried out to investigate whether the effect during learning is primarily on the availability of associations or on their formation. The learning decrement attributable to the drug used (30 per cent. nitrous oxide in oxygen) persisted on recovery from the drug and during subsequent learning under normal conditions. It is concluded that the effect of the drug is on acquisition rather than performance; that is, it acts so as to impede the formative process and does not merely obscure the progress of learning by blocking responses.