Being "Normal" can cause mental illness
I believe that the causes of most mental illnesses are genetic. However, life today goes at such a fast pace, people don't take time out to reflect, to have time to their selves, and to unwind, and hence they can suffer from mental illness or stress. Also, I believe that some mental illnesses is precipitated by people trying to conform to stupid, invisible and unwritten rules which are placed on them. For example, being happily married with two or three children, having a good and fairly well paid job, living in a nice house with a nice garden and having a good social life is what society classes as being normal. Yet many people, for whatever reasons, can't or don't achieve this status in their lifetime. So therefore, whilst striving to achieve it, they can become bitter, despondent or physically or mentally ill. So, I believe that some mental illnesses are caused by people conforming to, or trying to conform to, stupid rules.