The purpose of a system is what it does (POSIWID) is a systems thinking heuristic coined by Stafford Beer, who observed that there is “no point in claiming that the purpose of a system is to do what it constantly fails to do.” The term is widely used by systems theorists, and is generally invoked to counter the notion that the purpose of a system can be read from the intentions of those who design, operate, or promote it. When a system’s side effects or unintended consequences reveal that its behavior is poorly understood, then the POSIWID perspective can balance political understandings of system behavior with a more straightforwardly descriptive view.
Related: Duck test
Bibliography
“The Purpose of a System Is What It Does.” 2022. Wikipedia, October. https://en.wikipedia.org/w/index.php?title=The_purpose_of_a_system_is_what_it_does&oldid=1115506480.