Popularized by Charlie Munger (Poor Charlie's Almanack, 2005), after the mathematician Carl Gustav Jacobi's maxim "invert, always invert."
Turns a goal around to ask how it would fail, lists those failure modes, and treats each one as a rule to avoid.
When to reach for it
The path to success is vague but the ways to fail are easy to name, or a plan needs a hard list of what must never happen.
How it runs
- State the goal plainly.
- Ask what would guarantee failure.
- List as many failure modes as possible.
- Keep the ones that apply here.
- Turn each into a rule the plan must not break.
- Recheck the list as conditions change.
Where it sits in SOLVE eX
Go to the source
- Poor Charlie's Almanack, 2005
- Man muss immer umkehren (one must always invert), 19th century