More words from me:

What is a "dynamic" system? It is a system which can respond to changes in its environment. Dynamic systems have a range where they can respond to changes and return to a stable state when a stress is removed. But any dynamic system can be overloaded. When it is overloaded, a permanent or semi-permanent change takes place, and the system cannot return by itself to stable operation. A system that has been permanently altered will probably try to return to a stable condition, but it cannot do so on its own. It becomes unstable, or reaches a position of semi-stability in which it does not operate normally.

In humans people write about the "limbic" system, which has something to do with the regulation of emotions. It seems that the details of what parts of the brain form the limbic system and exactly what it does are not well known at this time. But if this system is stressed beyond its capacity to cope, it becomes unstable too. The disturbed system may eventually establish a condition of partial stability, trying to return to normal stability, but cannot do so without aid. The instabilities display themselves in the form, for instance in the case of manic-depressive (bipolar) illness, as a continual swing between the extremes of mania and depression. Other "mood disorders" such as obsessive or personality disorders show similar or related instabilities of emotion or mood and thought. Some remain more or less permanently in one extreme or another -- heightened anxiety, or depression, for instance. I think schizophrenia is one of these extreme states.

This is my picture of "mental illness" as a result of emotional stresses which overwhelm a system's ability to cope. A semi-permanent change takes place in which the system cannot return to normal functioning on its own. The system tries to return to health but has a very hard time doing so because of the changes which the original stresses have produced. Most often assistance is required, in the form of therapies or assisted self-help which promote learning new coping skills. The success of any such therapies or self-re-education will depend on how well the therapies incorporate accurate understanding of the nature of the dis-eases and how to go about reversing the damage. Poor understanding will lead to continued distress (have you noticed?) as the system attempts to heal but is frustrated in its attempts.