Imperfect Cognitions

Today's post is by Daniel Williams and Marcella Montagnese and it is the second in the series “Social Approaches to Delusions”. Daniel is an Early Career Research Fellow at Corpus Christi College, University of Cambridge, and Marcella is a doctoral student in the Department of Neuroimaging, Institute of Psychiatry, Psychology & Neuroscience, at King’s College London. Here Daniel and Marcella talk about their new paper “ Bayesian Psychiatry and the Social Focus of Delusions ”.   Daniel Williams As with many other areas of psychology and philosophy, the study of delusions is taking a social turn. This has different manifestations. For example, in an extremely interesting article , Sam Wilkinson argues that the very attribution of delusional status to certain beliefs is wrapped up in social practices of folk-epistemic approval and disapproval. To call something a delusion, Wilkinson argues, is not to describe – or at least not only to describe – reality but to express a certa...

In this post,  Daniel Williams , Postdoctoral Researcher in the Centre for Philosophical Psychology at the University of Antwerp, responds to last week's  post  from  Ben Tappin  and  Stephen Gadsby  about their recent paper " Biased belief in the Bayesian brain: A deeper look at the evidence ".  Ben Tappin and Stephen Gadsby have written an annoyingly good response to my paper, ‘ Hierarchical Bayesian Models of Delusion ’. Among other things, my paper claimed that there is little reason to think that belief formation in the neurotypical population is Bayesian. Tappin and Gadsby—along with Phil Corlett , and, in fact, just about everyone else I’ve spoken to about this—point out that my arguments for this claim were no good. Specifically, I argued that phenomena such as confirmation bias, motivated reasoning and the so-called “backfire effect” are difficult to reconcile with Bayesian models of belief formation. Tappin and Gadsb...

Today's post is by Dan Williams, a PhD candidate in the Faculty of Philosophy, at the University of Cambridge. If you had to bet on it, what’s the probability that your loved ones have been replaced by visually indistinguishable imposters? That your body is overrun with tiny parasites? That you’re dead? As strange as these possibilities are, each of them captures the content of well-known delusional beliefs: Capgras delusion, delusional parasitosis, and Cotard delusion respectively. Delusional beliefs come in a wide variety of forms and arise from a comparably diverse range of underlying causes. One of the deepest challenges in the contemporary mind sciences is to explain them. Why do people form such delusions? And why on earth do they retain them in the face of seemingly overwhelming evidence against them? My new paper “ Hierarchical Bayesian Models of Delusion ” presents a review and critique of a fascinating body of research in computational psychiatry that at...