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What’s the difference between a falsehood and a delusion? What’s the difference between QAnon falsehoods believed by millions, and a delusional belief of a patient with schizophrenia that Martians have taken over his intestines? Why does the family member of a friend deeply believe that the latter converted from one religion to another, when he did not?
These are examples of how in our personal and social lives, the lines between normal thinking and delusions are blurred. Many seem to think that “psychotic” conditions like schizophrenia are different categorically from normal mental health. In fact, psychotic states are partly normal, and normal thinking is partly psychotic.
Delusions are classically defined as “fixed false beliefs.” Sometimes it is added that they are outside the cultural norm for one’s social group. And sometimes it is added that they are based on evidence held against incontrovertible evidence to the contrary.
This blurring of normality and delusionality has been shown in many neuropsychological studies of normal persons. Features of thinking that are illogical or false — such as attribution bias, positive illusion, and confirmation bias — are well proven in normal persons.
So mentally healthy people think illogically and falsely. And so do delusional patients with psychotic diseases. The only difference is one of severity — of quantity, not quality.
Hence QAnon. Hence the angry family member.
People use false premises, combined with correct logic, to come to false conclusions. Or they start with correct premises, combined with faulty logic, to come to false conclusions. Either way, their beliefs are false. If repeated, and imbued with certain emotional qualities, like racial or class discrimination or sibling rivalry, these false beliefs become fixed. Contrary evidence is readily rejected or subject to logical analysis that can reveal reasons to doubt that evidence. And one might find friends who, presented with a similar set of limited premises and illogic, come to the same conclusions.
Suddenly normal human beings have fixed false beliefs, held against strong evidence to the contrary, which is consistent with a cultural peer group.
Supposedly mentally healthy people become indistinguishable from patients with delusions.
QAnon is not abnormal; wrong-headed family members are not unusual. Welcome to a mass of humanity in the heartland of America. Welcome to your average mean-spirited family member.
In the past, critics of psychiatry said that the profession labeled schizophrenia in those who were social nonconformists. Maybe the reality is that people with schizophrenia are merely conforming to the illogic of social norms; they're just more obvious about it.
