Metaphorically speaking*, there's a spectrum between the blinds and the schizophrenics.
Assuming there's a firm reality out there, if blind people were the majority, would it be reasonable if they considered themselves normal & "others" liars/idiots/delusionals?(Naturally yes!)
Assuming the same thing, if schizophrenics were the majority, would it be reasonable if they considered themselves normal & "others" liars/idiots/blinds?(Naturally yes!)
The problem lies in the belief that reality is a firm, reliable experience for everyone, or else, there's something wrong with their receivers and not the reality itself.
* Since Blindness and Schizophrenia are not generally opposites.