Schizophrenia means you’re hallucinating. You’re not having a dialogue with yourself, you’re not “vocalising” your own thoughts. You are hearing noises — not always _voices_ — that appear real to you and appear to be coming from an external source.
And if they are voices, they can be A. very distracting, and B. kind of mean at times.
I’ll also note that hallucinations due to schizophrenia are not limited to audible ones. You can have visual hallucinations, tactile hallucinations, basically any sense you have.
(Edited to remove typos)
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