Hang on. Everyone is jumping to the conclusion that a perfectly normal teacher just happened to be grabbed and taken for an "emergency medical evaluation" because he had innocently written a book. It is also quite possible that he is actually suffering from mental illness -- schizophrenia often manifests itself in early adulthood, for example -- and that his books were originally written as a coping mechanism for the early stages of illness. Remember, approximately 1% of the population will suffer from schizotypal symptoms at some point in their lives.
The most likely explanation is that the teacher's behavior had grown erratic and he had shown signs of mental disorder that caused grave concern in his co-workers and friends.