Tuesday 25 June 2013

Delusional Cognition and Epistemic Possibility

Matthew Parrott
am currently a Mellon Postdoctoral Fellow at Oxford. Most of my research is in philosophy of mind, cognitive science, and psychiatry (although I also have a strong interest in Hume).  Among other things, I'm currently thinking a lot about delusions. 

It seems to me that most current philosophical work on delusions is heavily focused on two issues.  First, as we can see from this blog, there is a lively and engaging debate about whether delusions are doxastic states or some other kind of mental state.

Secondly, there are discussions about the best framework or model to adopt for explaining delusions - for example, whether we should adopt a one-factor or two-factor theory or whether some kind of Bayesian model could be developed to explain the onset of delusion. Although I think these are both fascinating issues, I also think delusions present us with other philosophical questions that are worth consideration, especially once we start to think of delusions as patterns of thinking or cognition, rather than states.  
To offer just one example, it seems to me that one puzzling aspect of delusional cognition is that subjects consider possibilities that would not even occur to most of us. Regardless of whether one comes to believe it or not, there is something odd about seriously entertaining the thought that an imposter has taken the place of one's spouse. This is true, I think, even on the assumption that subjects with the Capgras delusion have highly irregular experiences of familiar faces.
If this intuition is on the right track, it suggests that, at least in some cases, delusional subjects consider a set of things (propositions/hypotheses) to be possible that is different from what ordinary subjects do. This raises some interesting questions about ordinary empirical reasoning, hypothesis generation, and the different ways in which ordinary thinkers and delusional subjects envision modal space. 
In my most recent work, I begin to explore this last idea in more detail. I claim that delusional subjects have irregular conceptions of epistemic possibility and that this is a significant respect in which their cognition is disordered (those who are attending can hear more at the upcoming ESPP conference - espp2013.com).  If that is right, it naturally presents some further puzzles. Why do these subjects have such unusual conceptions of epistemic possibility? How does a subject's sense of what is possible influence belief fixation? These are the kinds of questions I am currently wondering about.
More generally, however, it seems to me that there are many underexplored issues when it comes to delusions, which makes it a very exciting time to work on imperfect cognitions...

Sunday 23 June 2013

Why can’t we think of mental disorders as being mental?

This post is by Matthew Broome.

Matthew Broome
I’ve recently taken up a new post as Senior Clinical Research Fellow in the Department of Psychiatry at the University of Oxford, but prior to that was Associate Clinical Professor of Psychiatry at Warwick University and Lecturer at the Institute of Psychiatry, King’s College London, and it was during a Journal Club at the IoP where I first met Lisa Bortolotti and we began our collaboration.

A month ago I was delighted to take part in a public philosophy event at the European Institute of the LSE, as part of their Consilience series, devoted to mental illness.  The format was that, together with two colleagues, Tim Thornton and Bonnie Evans, we were asked to talk about the nature of mental illness prior to the chair, Kristina Musholt, opening the discussion to the floor.  

Saturday 22 June 2013

Folk Epistemology and Knowledge Ascription

María G. Navarro

I am a postdoctoral ‘Juan de la Cierva’ fellow at the Institute of Philosophy of the Spanish National Research Council. Until the end of November this year I am a visiting fellow at the Department of Philosophy at Birmingham.

I am interested in how people reason and ascribe knowledge through the daily act of making interpretations.

In the very simple, fast and productive act of interpreting something as being something all of us use and project our beliefs, desires and actions. But not less important is that we produce interpretations in order to express, represent, and reason about knowledge. That implies that being capable of producing interpretations is not only related to folk psychology but also to folk epistemology. But what does ‘epistemology’ mean when we affirm that it may be ‘folk’?

Thursday 20 June 2013

Against Doxastic Theories of Delusion

Are delusions beliefs?
Delusions are formed in response to perceptual or sensory experiences, they interact with other mental states in a more or less intelligible fashion and they regulate behavior. Any mental state with these properties deserves to be called a belief, or so say doxastic theorists of delusion. The fact that delusions are irrational merely means that we need to search for the causes of irrationality rather than abandon the doxastic conception.

I disagree. Delusions also have some very un-belief like features. They are very resistant to counterevidence, often maintained with ambivalence, and also seem to involve a phenomenology and stance towards the world which is very dissimilar to that of someone trying to produce and verify an empirical hypothesis. John Nash the Fields medal winner (the Nobel prize for mathematics) and celebrity schizophrenic said of his delusions “ it’s kind of like a dream. In a dream it’s typical not to be rational.” Adoxastic theorists have variously argued that delusions while they have some belief like properties (as do dreams) are better conceived of as imaginary states or a distinctive type of propositional attitude.

Saturday 8 June 2013

Epistemic Urgency: a Positive Dimension to Reasoning Biases in Schizophrenia?

Gregory Yates
I am a Masters student in Philosophy of Mind and Cognitive Science at the University of Birmingham. My research interests here are centred on the experiences of patients diagnosed with schizophrenia. I am also involved with the CogWatch project at Birmingham, a European funded research initiative aiming to enhance the rehabilitation of patients suffering from neurological disorders. Much of my theoretical and practical work, then, concerns cognitions seen as ‘imperfect’!

An article posted to Imperfect Cognitions in May explored the often-overlooked positive-psychological qualities or ‘secondary gains’ (Graham, 2013) associated with manic-depressive illness. I would like to consider here whether anything similar can be found in psychotic disorders – namely, schizophrenia.

Friday 7 June 2013

Delusions in the DSM 5

This post is by Lisa Bortolotti.

How has the definition of delusions changed in the DSM 5? Here are some first impressions.

In the DSM-IV (Glossary) delusions were defined as follows:

Delusion. A false belief based on incorrect inference about external reality that is firmly sustained despite what almost everyone else believes and despite what constitutes incontrovertible and obvious proof or evidence to the contrary. The belief is not one ordinarily accepted by other members of the person's culture or subculture (e.g., it is not an article of religious faith). When a false belief involves a value judgment, it is regarded as a delusion only when the judgment is so extreme as to defy credibility.

Monday 3 June 2013

Rationality and Delusions

I am Professor of Philosophy at the University of Birmingham and I mainly work in the philosophy of psychology and psychiatry. I am also involved in the numerous activities of the Philosophy of Health and Happiness research cluster which I co-founded with Heather Widdows and Iain LawIn the last few years I have been mostly interested in delusions, and I have been very fortunate to work at a series of papers on delusions with psychiatrist and philosopher Matthew Broome.

Lisa Bortolotti
I am interested in clinical delusions in their own right, what they are, how they are formed, how they differ from other "imperfect cognitions", but I also think that the phenomenon of delusions can help us make progress with some long-standing issues in the philosophy of mind, such as the relationship between rationality and belief.

We tend to see delusions as the mark of madness. The content of some delusions is so bizarre as to invite scepticism about whether anybody can genuinely believe such things. And yet, people assert sincerely and with great conviction that they are dead (Cotard delusion), that their dear ones have been replaced by impostors (Capgras delusion), or that their neighbours are physically inserting thoughts into their heads (delusion of thought insertion).