US: Weird, unsupported beliefs count as a delusional disorder. Not you, theists.
Jerry Coyne quoting Peter Boghossian quoting the DSM-IV:
The following is the DSM-IV’s definition of delusion:
“A false belief based on incorrect inference about external reality that is firmly sustained despite what almost everyone else believes and despite what constitutes incontrovertible and obvious proof or evidence to the contrary. The belief is not one ordinarily accepted by other members of the person’s culture or subculture (e.g. it is not an article of religious faith). When a false belief involves a value judgment, it is regarded as a delusion only when the judgment is so extreme as to defy credibility. Delusional conviction occurs on a continuum and can sometimes be inferred from an individual’s behavior. It is often difficult to distinguish between a delusion and an overvalued idea (in which case the individual has an unreasonable belief or idea but does not hold it as firmly as is the case with a delusion)” (2000, p. 765).
Again, religion gets a pass in society. Why should someone’s belief be a delusion only if it’s held by a minority of people? In the important respect of being “an incorrect inference about external reality that is firmly sustained,” and one that “defies credibility,” religion is a delusion. But note how religious faith is specifically exempted. Further, many individuals’ religious behaviors do indicate a delusional conviction (falling on one’s knees and talking to an imaginary friend, eating wafers, bowing toward Mecca five times a day, and so on).
Richard Dawkins’s book was properly named The God Delusion, although of course that angered the faithful, who don’t want to be seen as delusional. If 80% of the population suddenly became schizophrenic, would that no longer be seen as a mental disorder because it’s common?