firm and fixed belief based on inadequate grounding
(Redirected from Delusions)

A delusion is a false belief held by a person. When doctors talk about delusions, they mean that the false belief is the result of some disease. This is usually a disease of the mind, such as paranoia, schizophrenia or bipolar disorder, but not always. Delusions can come in many forms, such as persecutory delusions (a belief that the person is always being attacked), grandiose delusions (a belief that the person is very special), religious delusions (a belief that the person is a god), and more.

The psychiatrist Karl Jaspers created the first criteria for a belief to be considered a delusion:[1]

  • The person with the delusion is completely convinced that it is true.
  • The delusion does not change even when it is proved to be wrong.
  • The delusion is improbable or strange.

However, these guidelines have been criticized because none of the criteria are necessary to have a delusion. Studies show that delusions can change in intensity and confidence over time.[2] Delusions also do not need to be false beliefs.[3] Some religious beliefs cannot be proved false, so they cannot be used for a diagnosis.[4]

A doctor or psychiatrist may say that a delusion is false because it seems to be improbable or strange. Because psychiatrists do not always investigate a person's claims completely, they will sometimes wrongly diagnose a patient as delusional.[5] This is called the Martha Mitchell effect, which was named after the wife of the attorney general in the Nixon administration. Martha Mitchell said illegal activity was happening in the White House. At the time, people thought she was mentally ill. However, she was proven right after the Watergate scandal.

Treating delusions is hard, but sometimes antipsychotics can be used. If the delusions are dangerous to the person or other people, the person may also be treated against their will.


  1. Jaspers, Karl (1913). Allgemeine Psychopathologie. Ein Leitfaden für Studierende, Ärzte und Psychologen. Berlin: J. Springer.
  2. Myin-Germeys, I.; Nicolson, N. A.; Delespaul, P. A. E. G. (April 2001). "The context of delusional experiences in the daily life of patients with schizophrenia". Psychological Medicine. 31 (3): 489–498. doi:10.1017/s0033291701003646. PMID 11305857.
  3. Spitzer M (1990). "On defining delusions". Compr Psychiatry. 31 (5): 377–97. doi:10.1016/0010-440X(90)90023-L. PMID 2225797.
  4. Young, A.W. (2000). "Wondrous strange: The neuropsychology of abnormal beliefs". In Coltheart, M.; Davis, M. (eds.). Pathologies of belief. Oxford: Blackwell. pp. 47–74. ISBN 0-631-22136-0.
  5. Maher B.A. (1988). "Anomalous experience and delusional thinking: The logic of explanations". In Oltmanns T., Maher B. (ed.). Delusional Beliefs. New York: Wiley Interscience. ISBN 0-471-83635-4.