Evidential Holism and Indispensability Arguments

The indispensability argument is a method for showing that abstract mathematical objects exist (call this mathematical Platonism). Various versions of this argument have been proposed (§1). Lately, commentators seem to have agreed that a holistic indispensability argument (§2) will not work, and that an explanatory indispensability argument is the best candidate. In this paper I argue that the dominant reasons for rejecting the holistic indispensability argument are mistaken. This is largely due to an overestimation of the consequences that follow from evidential holism. Nevertheless, the holistic indispensability argument should be rejected, but for a different reason (§3)—in order that an indispensability argument relying on holism can work, it must invoke an unmotivated version of evidential holism. Such an argument will be unsound. Correcting the argument with a proper construal of evidential holism means that it can no longer deliver mathematical Platonism as a conclusion: such an argument for Platonism will be invalid. I then show how the reasons for rejecting the holistic indispensability argument importantly constrain what kind of account of explanation will be permissible in explanatory versions (§4).     

Towards a cognitive resource limitations model of diminished expression in schizotypy

Diminished expression of speech is a pernicious feature of both schizophrenia and schizotypy--defined as the personality organization reflecting a putative genetic schizophrenia liability. As yet, the mechanism underlying diminished expression is unclear. We tested the hypothesis that diminished expression reflects a cognitive resource issue--that is, as cognitive resources are depleted, expression becomes diminished in individuals with psychometrically defined schizotypy. Acoustic analysis of natural speech was procured during experimentally manipulated baseline and high cognitive-load dual tasks and examined in 38 individuals with psychometrically defined schizotypy and 34 controls. For both groups, expression significantly decreased as a function of increased task demands, although there were no group differences in expression or magnitude of change across baseline to high cognitive-load conditions. Participants with self-reported constricted affect showed significant reductions in expression under high-load versus baseline speaking conditions relative to other schizotypal and control participants. Moreover, psychometrically defined schizotypal participants with poor cognitive performance on the high-load task, suggestive of depleted cognitive resources, also showed expressivity reductions compared with other participants. These findings suggest that diminished expression occurs as a function of limited cognitive resources in psychometrically defined schizotypy.     

Causal Inference from Descriptions of Experimental and Non-Experimental Research: Public Understanding of Correlation-Versus-Causation

The human tendency to conflate correlation with causation has been lamented by various scientists (Kida, 2006; Stanovich, 2009), and vivid examples of it can be found in both the media and peer-reviewed literature. However, there is little systematic data on the extent to which individuals conflate correlation with causation. In three experiments, we presented people with one of four research vignettes generated from the combination of two independent variables: whether the vignette described an experimental or non-experimental design, and whether it revealed a positive or negative association. Upon reading their vignette, participants selected inferences that could be drawn from the findings. Participants drew causal inferences from non-experimental vignettes as often as they did from experimental vignettes, and more frequently for causal statements and directions of association that fit with intuitive notions than for those that did not. We discuss our findings in relation to other biases in human thinking.     

Two cheers for Tanhā

The central character in Sartre's 1938 novel La Nausée, Antoine Roquentin, has lost his sense of things, and now the world appears to him as utterly unstable. Roquentin suffers from what he calls ‘nausea,’ a condition caused by an ontological intuition that the self, as well as the world through which that ‘self’ moves, lacks a substantial nature. The novel portrays Sartre's own philosophical account of the self in La transcendence de l'égo. Here Sartre argues that Husserl's account of consciousness is not radical enough; the ‘I’ or ego is a pseudo-source of activity (and Sartre thus draws very close to a particularly Buddhist account of personal identity). My essay questions Roquentin's response to his ontological insight: why is this the occasion for ‘nausea’? Why doesn't Roquentin (as King Milinda famously does) celebrate and embrace his ‘non-self’? I argue that Sartre's depiction of Roquentin's ailment, and the unsatisfactory solution he provides, misunderstands both the aggregate nature of things as well as authentically rendered consciousness-only (vijñaptimātra).     

Interpretations of voices in patients with hallucinations and non-patient controls: a comparison and predictors of distress in patients

BACKGROUND: This study tested the hypotheses that interpretations of voices will be associated with distress linked to auditory hallucinations, and that patients experiencing hallucinations will exhibit higher levels of negative interpretations in comparison with non-patients. METHOD: The Interpretation of Voices Inventory (British Journal of Clinical Psychology 41 (2002) 259) was administered to patients who met DSM-IV criteria for schizophrenia spectrum disorders with auditory hallucinations and non-patients. Patients were also assessed using a semi-structured interview to asses clinical dimensions of their voices. RESULTS: The results showed that people with psychosis who experience auditory hallucinations did exhibit higher levels of positive and negative interpretations of voices, in comparison to non-patients. Correlational analyses revealed that interpretations of voices were significantly associated with emotional, physical and cognitive characteristics of voices. Regression analyses demonstrated that physical characteristics of voices and metaphysical beliefs were significant predictors of emotional characteristics of voices. CONCLUSIONS: The theoretical and clinical implications of these findings are discussed.