What does it mean to say that someone is mentally ill?

What does it mean to say that someone is mentally ill? What…

What does it mean to say that someone is mentally ill? What criteria are usually considered to determine whether someone is mentally ill?

Should we use these criteria and are these methods appropriate for diagnosing mental illness?

Mental illnesses are health conditions involving changes in emotion, thinking or behavior (or a combination of these). Mental illnesses can be associated with distress and/or problems functioning in social, work or family activities.

What are the criteria for determining mental illness?
In general, in order to meet the criteria for mental illness, your symptoms must cause significant distress or interfere with your social, occupational, or educational functioning and last for a defined period of time.