Abstract

This chapter gives an illustrated overview of recent philosophical work on the concept of delusion. Drawing on a number of case vignettes, examples are given of the wide range of theories that has been advanced to explain this most challenging of experiences. Some have agreed with the philosophical founder of modern descriptive psychopathology, Karl Jaspers, that delusions are “ununderstandable.” The large majority, though, has sought to understand delusion in terms of aberrations of one kind or another either of beliefs or of the grounds or preconditions for beliefs. As a project in understanding, these theories offer helpful insights. A further group of theories focuses on the agential aspects of delusion as reflected, for example, in their role in the insanity defense. Agential theories converge with the person-centered approaches of contemporary empirical and clinical work on delusion. Such approaches bring an additional level of complexity in the form of delusions that are not pathological but adaptive in the life of the person concerned. As such they show the challenge of understanding delusion to be a project not just of understanding but of mutual understanding.