TBD

Abstract

The problem that we encounter is that we are always working with great uncertainty. The bulk of our activities occur before there is even a system to consider; there is only an idea of a system — and perhaps some bits and pieces to see and touch — but nothing that has been assembled and whose function we can observe. So we end up “imagining” what it is going to be like, and we make expert “judgments” (guesses?). Because we are just imagining a future system, we are unsure about many — perhaps most — of the details. Even if we have a finished prototype in front of us, we know very little about how the pieces were made, assembled or tested. We don’t know if there are defects in the design, or defects in manufacturing. We don’t really know about the details of the use environment. We don’t know much about the people who will use it, or what imaginative uses it might be put through.