ABSTRACT
It may seem odd to think that a poktteal decision could be a deliberate part of "system design:' Most of us wouldn't see any similarity between the design decisions that led to the creation of the Reach toothbrush and the policy decisions made by politicians, public servants and non-governmental organizations that led to the creation of the Kyoto protocol. You can hold a toothbrush in your hand and use it directly to complete the task for which it was designed. Policy decisions can't be held in your hand. For instance, an international accord is an abstract cultural constraint, and although it can be physically written down on paper, you can't pick up and use that piece of paper to achieve the goals that the legislation was intended to fulfill - at least, not in any direct sense.
