ยง Sciences of the artificial

A bridge under its usual conditions of service, behaves simply as a relatively smooth level surface. Only when it has been overloaded do we learn the physical properties of the materials from which it is built.
Ohm's law was suggested to its discovered by its analogy with some simple hydraulic phenomena.
Why simulation is useful:
A NASA launched satellite is surely an artificial object, but we usually do not think of it as simulating the moon; It simply obeys the same laws.
Babbage introduced the words "Mill" and "Store"
The focal concern of Economics is allocation of scarce resources.
We can use a theory (say a theory of profit-loss) either positively, as an explaiation, or normatively, as a way to guide how we should run a firm.