I was involved in an interesting but unconcluded discussion last night about defining the purpose of a government department. After overnight brewing…

I’d say the purpose of a system is a mental construct: it’s not intrinsic. A screwdriver doesn’t have a purpose: the carpenter has a use for it.

Although screwdrivers are simple systems we do have multiple uses for them: driving screws (obviously) but there’s also opening paint cans, jemmying windows, scraping away annoying globs of glue and so on. Purpose is not simple.

And what about more sophisticated systems? What’s the purpose of a supermarket? Is it to sell food, to nourish customers or to make money; or all of the above; or something else?

Whatever is written down, purpose exists in our heads. It’s the sum of a collection of shifting, context-dependent and partially subconscious personal perspectives. It's messy: something more for continuing and wide conversation than for defining.