Suggested 8 criteria to see if someone was mentally healthy;- No symptoms of distress- Able to think rationally- Has the ability to self-actualise- Can cope with stress
Proposed that when someone isn't coping they will no longer conform to interpersonal rules, experience personal distress and behave in a way that is irrational/dangerous
A person may cross the line between normal and abnormal when they can no longer cope with the demands of everyday life. They are unable to maintain basic standards of nutrition, hygiene can't hold down a job or maintain a relationship.