Descriptive Psychopathology: The Signs and Symptoms of ...

11Delusions and abnormal thought contentNevertheless, I am convinced that the only method by which we shall attain an insight intothe mysterious phenomena of unsound mind, is to keep ever before us the fact that disorderof the mind means disorder of the brain, and that the latter is an organ liable to disease anddisturbance, like other organs of the body, to be investigated by the same methods, and subject tothe same laws. In speaking of the pathology of insanity, I have endeavored to keep this in view. 1The standard definition of delusion is: A false notion inconsistent with theperson’s background that is held with great conviction despite clear evidenceto the contrary. The definition does not characterize the delusional process,only the end result.Like delusions, obsessions and over-valued ideas are also false notions heldwith great conviction despite evidence to the contrary. They also result fromfaulty conclusions, but the connection between the evidence and the conclusionmakes better sense. Germs can be dangerous and extraterrestrial life may exist,but a life consumed by these notions is maladaptive. What descriptively definesa delusion is the greater leap from the evidence to the idea (e.g. “my poorcell phone service means my neighbors are aiming electronic beams at myhouse”), or the lack of any reasonable understanding of how the conclusionwas reached (e.g. “they are aiming the electronic beam because the neighbor’snew dog has brown spots”). Karl Jaspers considered the lack of understandabilityof how the patient reached the false conclusion to be the defining factorof a delusional idea. 2The content of the delusional idea can be mundane (e.g. my spouse is unfaithful)or fantastic (e.g. “my spouse is an alien here to conquer the earth”).Compared to obsessions and over-valued ideas, delusional ideas are more oftenculturally or class deviant (e.g. the stockbroker believes a witch inhabits hiscomputer), or overtly strange (e.g. the patient is convinced he is dead). Delusionalideas also reflect a psychopathological process that distinguishes them fromobsessions and over-valued ideas.272