Posted by Ben Simo
... as the little boy said, "Today we learned how to spell 'banana', but we didn't learn when to stop." ... In honor of that little boy, we can elevate his idea to a principle, The Banana Principle:
Heuristic devices don't tell you when to stop.
- Gerald M. Weinberg,
An Introduction to General Systems Thinking
I just had the following exchange with my 12 year old daughter Jessica.
Me: How do software testers know when to stop testing something?
Jessica: When you die! . . . Or when you get really tired of it.
The Banana Principle does not mean that heuristics cannot be useful in determining when to stop. It means that heuristics do not tell us when to stop using the heuristic. There is a tendency to start transforming the most useful heuristics into laws -- in our minds. Heuristics should help us think and not replace thinking. This includes continual questioning of even the most useful heuristics.