ABSTRACT

This final chapter is not intended to summarize the text. The intention is to consider selected aspects of the topics from the particular viewpoint that provides what has been claimed to be a unified treatment. We should now be in a position to take a broad view of the field, to see the relationships between the topics, and also to acknowledge some limitations created by the choice of a unifying principle. More particularly, we should also be able to consider some of the choices between methods that we face in applications.