The central hypothesis of this book, Delusions and Beliefs: A Philosophical Inquiry (Routledge, 2019), is that delusions are malfunctional beliefs (Chapter 1); they belong to the category belief 2) but, unlike mundane false or irrational beliefs, fail perform some functions 3). More precisely, directly indirectly involve malfunctioning cognitive mechanisms, which empirically supported by two-fa...

The hypothesis that persecutory delusions function to enhance self-esteem implies that patients will show normal explicit, but low implicit self-esteem. As evidence for this has been inconsistent, our study assessed delusional state, explicit and implicit self-esteem and depression in a large sample (n=139) of schizophrenia patients with acute persecutory delusions (n=28), patients with remitte...

We proceed to describe a model for the formation and maintenance of polythematic delusions encountered in schizophrenia, which is in adequacy with Brendan Maher's account of delusions. Polythematic delusions are considered here as the conclusions of arguments triggered by apophenia that include some very common errors of reasoning such as post hoc fallacy and confirmation bias. We describe firs...

Jaspers’ textbook General Psychopathology has in the past been described as the ‘most important single book on the aims and logic of psychological medicine’ (Shepherd, 1990). In recent years it seems to have rather fallen off the psychiatric syllabus. Its diminished importance is exemplified by changing opinions about delusions. Nowadays, delusions are considered by many to lie on a continuum w...

The results of many researches indicate that individuals with delusions reveal the reasoning bias. In probabilistic reasoning tasks they reveal hastiness in decision-making. The individuals with delusions request less information than non-deluded individuals, even if additional data is easily available. What is more, they also prove to be convinced to a greater extend of having made the right d...

In this article I ask whether elaborated and systematized delusions emerging in the context of schizophrenia have the potential for epistemic innocence. Cognitions are epistemically innocent if they have significant epistemic benefits that could not be attained otherwise. In particular, I propose that a cognition is epistemically innocent if it delivers some significant epistemic benefit to a g...

INTRODUCTION A preliminary cognitive model of grandiose delusions has been put forward suggesting that persecutory and grandiose delusions shared distinct, yet overlapping psychological processes. This study aims to test this model and hypothesises that participants experiencing grandiose delusions may demonstrate a theory of mind (ToM) impairment and differences in attributional style compared...

Delusions are widely believed to reflect disturbed cognitive function, but the nature of this remains elusive. The "un-Cartesian" cognitive-linguistic hypothesis maintains (a) that there is no thought separate from language, that is, there is no distinct mental space removed from language where "thinking" takes place; and (b) that a somewhat broadened concept of grammar is responsible for besto...