Feeling like a savant and worries of delusion of grandeur

The delusion of grandeur sounds like a trait of narcissism, but I suppose things are not as simple as that. 

When you tell others that you are ten times more intelligent than them, is that based on pure logic and rationality, or is it because you want to put them down? And if you think you are more intelligent, is that in correspondance with your interests, or do you think you are more intelligent at everything compared to them?

The confusing part is that Delusional Disorder itself is part of Schizophrenia Spectrum and Other Psychotic Disorders. I think in theory Narcissistic Personality Disorder should be part of Schizophrenia Spectrum and Other Psychotic Disorders as well. But, that is just a theory.

I think that schizophrenia has hallucinations of imagery and/or sounds, which is sort of like overlapping the dream state with reality. 

But NPD are not hallucinating or having the that type of delusion, and to place NPD under the the schizophrenia spectrum would not seem right to me. 

NPD's delusion of grandeur, is just their strong belief that they are better than everyone else, as if it's a fact. It's different from schizophrenia, who hallucinates imagery and/or sounds that are not there, well, unless NPD takes some sort of hallucinatory drug to induce it, I suppose. But in general, Schizophrenia behavior and traits don't really match those with NPD. 

I think that schizophrenia has hallucinations of imagery and/or sounds, which is sort of like overlapping the dream state with reality. 

But NPD are not hallucinating or having the that type of delusion, and to place NPD under the the schizophrenia spectrum would not seem right to me. 

NPD's delusion of grandeur, is just their strong belief that they are better than everyone else, as if it's a fact. It's different from schizophrenia, who hallucinates imagery and/or sounds that are not there, well, unless NPD takes some sort of hallucinatory drug to induce it, I suppose. But in general, Schizophrenia behavior and traits don't really match those with NPD. 

That does make sense, although not all people with Schizophrenia have hallucinations, and it depends on what Schizophrenia it is.

But not all schizophrenics suffer from delusions of grandeur though. I really suppose it really depends on what their hallucination is about. I mean NPD doesn't really hallucinate or see things that are not there. However, there's likely someone out there diagnosed with both schizophrenia and NPD, because of their brain's wiring. I mean it's interesting to think about.

And, so is behavior in Delusional Disorder, it's different than Schizophrenia, but is part of the same spectrum of Schizophrenia and NPD is associated with Delusion of granduer.