ECO.Preface:2 - Problem and forces - Locally sound contributions can fail together

A calculation may be correct for its inputs while a quoted resource is unavailable. A prototype may work while no customer will commit. A customer and supplier may agree while imposing a cost on a shared resource. A rule may allocate that resource correctly under one flow and fail when the flow changes. A better technology may use less per result and more in total.

These failures require connections among methods. Treating economics only as monetary calculation loses the formation of alternatives, access and coordination. Treating it only as a general account of purposeful action leaves practitioners without the economic operations which connect particular plans and institutions.

The language uses both formal models and qualitative reasoning where their conditions fit. A mathematical result follows from its admitted construction; using it to describe actual people, organizations or markets requires the corresponding grounds. Numerical probabilities are useful when defensible, while conditional alternatives can be sufficient for a decision.

Further inquiry has its own whole cost, including delay and work displaced. C.11.DUA helps compare it with using adequate current information, changing the action, accepting a bounded uncertainty or stopping. There is no requirement to prove every source anecdote or gather every possible observation before acting.