the purpose of a system is you can't always get what you wa…

the purpose of a system is you can't always get what you want

• The author is reconsidering the value of the "POSIWID" principle, finding it more confusing than helpful despite its catchy nature.

• POSIWID stands for "The Purpose Of A System Is What It Does" and is not a fundamental principle of cybernetics or an axiom of Stafford Beer's Viable Systems Model.

• POSIWID is intended as a heuristic to help people understand how to apply the Viable Systems Model, not as a universal truth.

• The principle should only be applied to systems that are potentially viable and ongoing, not to malfunctioning or temporary states.

• A common misconception is that POSIWID should be expanded to mean "the purpose of a system is what it systematically does, on an ongoing basis, with the permission of the other systems which form its environment."

• The purpose of a system is always a compromise with other systems in its environment, as emphasized by Beer.

• The author provides an example where a reviewer concluded that the British rail network's purpose is to disincentivize train journeys, which is more accurate than saying its purpose is to provide comfortable and affordable travel.

• The use of "purpose" language can be confusing as it seems to attribute mental states to systems, but it is meant to help decide what information is relevant for analysis.

• The author argues that understanding the rail network as a rationing system affects the kind of information considered relevant for analysis, such as political and geographical factors.

• Despite its defensibility and importance, POSIWID is complicated and often confusing, leading the author to decide to use it less frequently in the future.

• The author appreciates POSIWID as a reminder to engage with what is actually happening rather than what was planned or expected, likening it to Maya Angelou's quote about believing people's actions.

• The author concludes that POSIWID is essentially a way of saying that analysis is useless without understanding the System 5 (the decision-making and policy-setting part) of what is being analyzed.