R. D. Laing) have argued that this leads to the diagnosis of delusions being based on the subjective understanding of a particular psychiatrist, who may not have access to all the information that might make a belief otherwise interpretable. Another difficulty with the diagnosis of delusions is that almost all of these features can be found in "normal" beliefs. Many religious beliefs hold exactly the same features, yet are not universally considered delusional. For instance, if a person was holding a true belief then they will of course persist with it. This can cause the disorder to be misdiagnosed by psychiatrists. These factors have led the psychiatrist Anthony David to write that "there is no acceptable (rather than accepted) definition of a delusion." In popular culture In the 2010 psychological thriller Shutter Island, directed by Martin Scorsese and starring Leonardo DiCaprio, delusional disorder is portrayed along with other disorders. An Indian movie Anantaram (Thereafter) directed by Adoor Gopalakrishnan also portrays the complex nature of delusions. The plot of the French movie He Loves Me... He Loves Me Not revolves around a case of erotomania, as does the plot of the Ian McEwan novel, Enduring Love. See also Delusional parasitosis Monothematic delusions Morgellons Paranoia Shared delusional disorder References Further reading McDermott, Sarah (22 February 2018), "'The story of a weird world I was warned never to tell'", BBC News. [A related case study.] Munro, A. (1999) Delusional Disorder: Paranoia and Related Illnesses. Cambridge: Cambridge University Press. . Sims, A. (1995) Symptoms in the mind: An introduction to descriptive psychopathology. Edinburgh: Elsevier Science Ltd. . External links Paranoia Psychosis