Summary
‘The purpose of a system is what it does’ is a rule of thumb from systems thinking: to understand a system, look at what it reliably produces, whatever its designers say it is for. It comes from the British cybernetician Stafford Beer, who used the phrase in ‘The Heart of Enterprise’ (1979) and later talks. In 2001 he called it bald fact, “a better starting point in seeking understanding than the familiar attributions of good intention”.
One of his examples: a railway whose purpose, from his seat, was to put him off rail travel. Purpose, he added, is read by an observer. The acronym POSIWID seems to have come later.
Rationale
We can turn Beer’s test on ourselves. Part 1 admits we may live harmful dispositions out “even through work that seeks to stop and repair harm”; effects, more than intentions, show which.