Religion is a fine example of a shared delusion. I was at a catholic funeral yesterday, and it was a fine example of the life after death delusion of those folks. I may not know what is really true, but I can separate out some of the obvious delusions. Learning to live in reality may be the ultimate answer.
Realizing that life can become a delusion may be the way to prevent radicalization. If someone is selling it, it probably is a delusion. We all need to cooperate to for us to all survive well, and that gives each of us the best chance of surviving well. There will be the sociopaths, egomaniacs and psychopaths who realize that they can take a bit more and live better still, but we know they are sociopaths, egomaniacs and psychopaths. Oh well, predictors and assholes exist.
Where is this going?
Predictors, sociopaths, egomaniacs, psychopaths and other types of asshole exist, as well as those living their delusion. We need to be aware of them, and not become there targets or get in there way. (Should that be their? but they are less than the ideal human, there will do) The deluded may be the most dangerous for they believe they are in the right. It may be that belief, that they are right, that makes all these groups the most dangerous of peoples.