In reading over some posts, and being rightfully called on the carpet by some posters, I wanted to clarify the issue of mental illness vs. evil in the VA Tech shootings. Here is my position as clearly as I can explain it.
Evil exists. As a Catholic, I believe that God exists, and, so does evil.
But, as a mental illness advocate and consumer, I firmly believe that mental illness certainly exists and has nothing (in general) to do with evil. Mental illness is a brain disorder and by definition, causes various behaviors.
There are situations where an otherwise "sane" (read, non-mentally ill) person commits horrible atrocities. It is in those situations that it is easiest to see the work of evil.
But, the fact that evil exists, does not, by definition mean that the person committing those horrible acts cannot suffer from mental illness.
Mental illness does not preclude intelligence--it often accompanies it. People who suffer from mental illness are quite capable of planning and forethought in many cases. The fact that an act is planned, does not mean the perpetrator does not suffer from mental illness.
Mental illness is physical and for the most part, treatable.
In trying to balance my belief in the medical model of mental illness with my belief in the existence of evil, I missed the boat. For that, I apologize.