All people have a robust inner monologue. For some, it is strong enough to take the form of a “mental illness.” Regardless of whether a character’s inner voices seem to fall within a normal range, the message of that voice is still about who the character is as a person.
“In the past few years I have been working with some colleagues at the Schizophrenia Research Foundation in Chennai, India, to compare the voice-hearing experience of people with schizophrenia in the United States and India….in our sample of 20 comparable cases from each country, the voices heard by patients in Chennai are considerably less violent…”
He quoted one American as describing what his voices said to him: “Usually it’s like torturing people to take their eyes out with a fork, or cut off someone’s head and drink the blood, that kind of stuff.” Whereas the Indians’ voices told them “to do domestic chores — to cook, clean, eat, bathe, to ‘go to the kitchen, prepare food.'”
In this sentence in his 2006 book The God Delusion, Richard Dawkins similarly implied that the content of our hallucinations depends on our cultural assumptions:
“If we are gullible, we don’t recognize hallucination or lucid dreaming for what it is and we claim to have seen or heard a ghost; or an angel; or God; or — especially if we happen to be young, female and Catholic — the Virgin Mary.”
In other words, no one who did not have some prior cultural exposure to a particular god would hallucinate that god.
This observation applies to characters who are “mentally ill” and those who are not. A character’s inner monologue tells you more about who that character is than about their illness or about any figment of their imagination. Less obviously, the lessons a character takes away from their inner monologue tell you more about who that person is than about any “objective truth.”
And you may know this:
The characters you hallucinate tell you about you.