For me, delirium is only the fact of feeling things very strongly, even if we may be led to think: "how can this person think that? his brain must be bubbling completely."
, for example during discussions with a friend who was still a little racist I understood that she was convinced that black people were more delinquent, lying and wanted to harm the France and people of French origin, so it makes sense to want to fire them from the France if you think that. By arguing at length, I managed to persuade her that these are mostly ideas that she had because I meet many black or Arab people and it is only rarely that they cause me problems, in the same way as white people. Although maybe after the end of this conversation these ideas came back, and I explained to him that even if, let's imagine, there is a little more delinquency among these people, then accusing them all of delinquency is a bad thing: it wrongly accuses them, makes them suffer and sets people against them.
It is the same for schizophrenia and other delusions: they have an idea in mind that could be understood, although sometimes during their reasoning they make shortcuts, leading to some conclusions that seem foolish, they are only half senseless in reality. These are ideas, I think, generally false, they do not realize that they are false on the one hand because they have an intuition that leads to believe that certain ideas of persecution are likely, where the majority of people think they are unlikely, and on the other hand because shortcuts are made because their mind harassed with disturbing ideas n 'can't see that there is an inconsistency in this shortcut.
The speed with which these ideas appear and the force with which these ideas persuade them is too strong to be able to fight against it by discussion, even if by discussion we can make it clear that something is wrong and that one of the ideas is wrong, the disturbing ideas will eventually come back, so we must take a treatment.
I think it's something biological that creates schizophrenia, something that kind of disrupts all the neurons. Indeed it affects a little all the functionalities of the brain: Interpretation, sight, hearing, smell, touch, will, anxiety, sleep.