I hope this never happens to me. When I was 26 I had a delusion. It wasn't the CIA spying on me or anything like that, but it was... Definitely a delusion of some kind. I don't feel comfortable sharing it here because it is very embarrassing for me. I went to a psychologist about it and we did some therapy and some kind of DSM test (I forgot which). It was her opinion that I was not schizophrenic or delusional, but that I'd had a break from reality due to extreme stress (I had been through a shitton of serious life changing events). This was the only time a delusion ever happened, and it was only on one subject. Sadly my grandmother is schizophrenic so I will have to be on the lookout for signs for the rest of my damn life. It is scary as hell... I've only experienced it on such a small plane, so I can't imagine what your brother felt when he realized he had been wrong about things he was sure were facts (everybody's wrong about facts sometimes, but usually delusions are personal and intricate webs of many untrue statements). I really hope you've been kind to your brother. It is hard being... Well, feeling as though you are crazy... Not being able to trust your own brain. I'm always worried I've lost it and no one has the heart to tell me. It's also very hard for me to make friends. I'm glad he is on the mend and making connections!