Hearing voices or other sounds that aren't really there is a distinguishing characteristic of paranoid schizophrenia. Often, these auditory hallucinations do involve voices. People with paranoid schizophrenia may actually hear voices that are often very unpleasant, harassing them or telling them to do harmful things. Because they cannot interpret reality, they may grow to have delusions because of the voices. This can cause serious problems, as people with the disorder may harm themselves or put themselves in dangerous situations because of these hallucinations.