Clinical psychologist Professor Daniel Freeman continues his exploration of delusions, looking at both historic and contemporary case studies.

In this programme he examines the Delusion of Despair.

He begins with the story of Francis Spira, the 15th-century Italian lawyer who believed he was damned by God – a case of delusional thinking that haunted the 16th and 17th centuries, and inspired Christopher Marlowe’s Doctor Faustus.

In the last 20 years, our appreciation and understanding of delusions - a strongly held, fixed, false belief - has begun to shift enormously. Delusional ideas are remarkably common in the population. And delusions are closely tied to a person’s sense of self, their views of the world and what is happening in the environment.

Daniel talks to Cheryl to find out how an excessively negative sense of self can set in motion a troubling line of thought that other people may be judging you, observing you, and waiting to punish you.

Produced by Victoria Shepherd and Eve Streeter A Greenpoint production for BBC Radio 4