Slightly random thread. But is that line "Crazy people don't know they're crazy" true?
A lot of the people I know with schizophrenia or the like refuse to accept there is something wrong, or suggest that it isn't a mental disorder but rather something else.
Look up
anosognosia and
insight.
I think that the blatant neurological forms of anosognosia (read: a lack of knowledge
'a-gnosis' about one's own disease
'nosos') lends biological plausibility to the idea that some psychiatric disorders, for which the neurobiology is generally more poorly understood, could be characterised by a lack of self-insight.
The classic example from neurology is unilateral neglect in which a lesion of the (right) brain causes the individual to neglect the left side of the world, such that if you get them to copy or draw a picture it will
end up like this. The neuroscientist Ramachandran did experiments with such patients in which a mirror on their right hand side (which they could see) showed the reflection of a pen which sat on their left (neglected) side. When asked to pick up the pen the patients would either bump their hands into the mirror or stand up and look behind the mirror. They simply could not comprehend that the pen could be on their left, presumably because the left side of space was no longer a part of their cognitive map of the world. In the same vein they could not understand their error/disease --> hence 'anosognosia'.
Also, there is a big difference between denying the presence of abnormal cognitive states (e.g. denying delusions, hallucinations and bizarre behaviors = a lack of insight) and denying a label like schizophrenia, though there is at least some overlap. You can disagree with the medicalised entity that is schizophrenia (e.g. by disagreeing with the stress-diathesis model, claims of genetic underpinning and the importance of disturbed dopaminergic signalling) but recognise that one has had hallucinations, for example. A lot of this depends on your philosophy of personal identity and the mind.