We Are All Susceptible To Delusions

Former psychologist Frank Tallis on “monosymptomatic delusion” — in which an otherwise sane person latches onto one big outlandish idea. It is possibly responsible for both demonic possession and falling in love. Via New Scientist:

Once a patient came in and said: “I am possessed by a demon.” This guy wasn’t insane, he wasn’t schizophrenic – he just had this particular belief. In my day we called it “monosymptomatic delusion”, but now it would be called something like “delusional disorder”. That’s when you’re completely sound and reasonable in every respect except you have one belief that is absolutely bonkers.

You have to have an openness to it. Lots of people are open to all kinds of spiritual and magical beliefs. An individual could have a perfectly harmless interest in the supernatural but then something happens that triggers this delusion and they get stuck with it, reinforcing it by piling up one misinterpretation after another.

Could anyone end up with delusions like these? Theoretically, yes, in the right circumstances. Maybe we all get such episodes in our lives. It’s not that unusual for people to think they are seriously ill without much evidence. The big one is people suspecting that their spouse is cheating on them. Morbid obsessions about infidelity are relatively common and produce spectacular behaviours, often in individuals who otherwise are OK. In a way, falling in love is kind of monosymptomatic delusion. Even though you’re a rational person, you can engage in all kinds of irrational behaviour because you are fixated on a particular individual.

  • PossiblyMaybe

    “That’s when you’re completely sound and reasonable in every respect except you have one belief that is absolutely bonkers” I have “faith” that humanity will one day rise up and fulfill all of its potential. This article reinforces what I already feared…that I am utterly delusional :-)

    • The only thing to get is money

      OH cheer up lad. We are all delusional. We live in our confusions, illusions, delusions. Otherwise we drop dead. As there would be nothing to attain or understand.

  • http://twitter.com/jasonpaulhayes jasonpaulhayes

    When an entire culture adopts a  “monosymptomatic delusion” it becomes a “polysymptomatic delusion” and therein lies the struggle of our time.

    • http://hormeticminds.blogspot.com/ Chaorder Gradient

      i woulda thought polysymptomatic delusion would be something like a major chuck of New Age belief, or maybe the delusional world Alex Jones lives in.

  • Simiantongue

    “Susceptible to delusions”? That’s all I have left.

  • Liam_McGonagle

    Well, what is a delusion?  A belief that falls outside of the public consensus?  Or a belief whose operation doesn’t produce the desired results?

    The two definitions are often diametrically opposed.  If you could dose David Cameron or George Osborne will a couple gallons of Sodium Pentathol each, they may have some interestingly apropos observations on the topic of the delusion that austerity and tax cuts for the wealthy create jobs.

  • http://www.zazzle.com/fantoccini* Gort


    Please define.

  • Trance-formation
  • Nunzio X

    I regularly drive through my local Reality Tunnel, then take a left at Consensus Reality Avenue.

    (Going against the flow of traffic, of course.)

  • anon

    So basically all christians, muslims and jews have this disorder, or did I miss something?

    • http://www.facebook.com/schoeve David Schoeve

      Its pretty delusional to believe in a god but its not a disorder its just what people been told for so long. Its slowly changing and people are becoming more intelligent as time goes on, but some people still hold on to their beliefs even if they dont particularly believe in the teachings anymore. Humans go figure.