Post History

Source: https://writers.stackexchange.com/a/31753
License name: CC BY-SA 3.0
License URL: https://creativecommons.org/licenses/by-sa/3.0/

Source: https://writers.stackexchange.com/a/31753
License name: CC BY-SA 3.0
License URL: https://creativecommons.org/licenses/by-sa/3.0/

First figure out **_why_** you need this character to be insane. What insane act or decision must they make in order to advance your plot?

Insanity generally involves a **failing model** of the world and people in it. Like truly believing if you hold a white feather, you will be able to fly if you leap off a building. A man truly believing his dog talks to him and tells him certain people are immoral and evil and must be killed. A man truly believing the voice in his head is God, granting him permission to kidnap a fourteen year old girl and make her his wife. Or a man truly believing through fervent prayer that God told him to murder a doctor for performing abortions.

These are all failed ideas about how the real world works. A person is NOT insane unless they have such a mental model that will put them in danger or other people in danger. Their **reasoning** is broken because they believe things that are just not true, about other people, about God, about physics, about magic or the supernatural or the state of the world.

Truth can be relative, of course. Four centuries ago is was common to believe that a magical object existed that could turn common things into gold. No such thing exists, but it was not insane to believe it **could** exist, or even go in search of it. Today, we might classify such beliefs and actions as insane.

That said, for modern characters, the way to portray insanity is best done through action (as other answers say) but for **dialogue** the best way is to develop exactly what the rules are of this characters failed model of how things (and people) work and behave and believe, then have their reasons for doing things depend upon that failed model. You can reveal their "crazy" beliefs in dialogue as the justification for doing what they are doing.

Their dialogue doesn't have to necessarily be distracted, or frantic, or anything of the sort. It can be like talking to a professor. It is their bad **reasoning** from bad **principles** that betrays them as insane.

Original score: 1