Inversion

Inversion

“Invert, always invert.” The advice attributed to mathematician Carl Gustav Jacob Jacobi is man muss immer umkehren—you must always invert. In everyday planning, questions such as “How can I succeed?” and “What should I do?” can be complemented by “What would guarantee failure?” and “What am I trying to avoid?” The answers may expose risks that the original questions left out.

Inversion changes the question you are trying to answer. Alongside “What is the best way to do X?” ask “What is the worst thing I could do for X, and how do I avoid that?” Identifying a bad approach can be easier than identifying the best one. Avoiding it is useful, though it does not supply everything a successful plan needs.

Munger illustrates inversion with a rustic who says, “I want to know where I’m going to die so I’ll never go there.” The joke suggests starting with an outcome to avoid. In his 1986 commencement speech, Munger describes ways to create misery, including addiction, resentment, unreliability, and refusing to learn from mistakes. He makes a similar move with the questions “How can I help India?” and “How can I hurt India?” Thinking through the second question may reveal damaging policies to avoid; it complements the work of finding helpful ones.

Inversion in everyday goals. Consider “I want to lose ten pounds.” Asking what you want to avoid may clarify the reason for that goal. Perhaps you get winded when playing with your children or want to discuss diabetes prevention with your doctor. Questions such as “How do I avoid being out of breath with my children?” and “What changes must I make to dodge diabetes?” can help identify a more specific concern and an appropriate next step. The reframing does not make every health risk preventable.

In business, inversion means asking what would cause a plan to fail, which risks are avoidable, and what safeguards would help. Buffett and Munger’s emphasis on avoiding difficult business problems is one application. A plan still needs a way to create value after obvious hazards have been addressed.

Innovation by working backward. A related approach starts with a desired ability and identifies what would make it possible. Marie Van Brittan Brown, a nurse in Queens, New York, wanted greater security at home. She and her husband applied for a patent in 1966 for a home-security system with a camera moving between peepholes, an indoor monitor, an intercom, and an alarm. Their design illustrates the question: What would let a resident see and communicate with a visitor without opening the door? This is a way to interpret the design, rather than a record of Brown’s private thought process.

Florence Nightingale’s use of mortality statistics to advocate sanitary reform offers another illustration. Alongside treating soldiers’ illnesses, the analysis directed attention to conditions contributing to deaths. The questions “How do we prevent this from happening in the first place?” and “How do we fix it?” capture the difference between prevention and response.

To try inversion, list ways a plan could fail, identify the causes you can affect, and decide how to address them. Separately, work backward from the desired result to find necessary conditions. Sun Tzu’s advice offers an analogy for avoiding costly conflict: “Hence to fight and conquer in all your battles is not supreme excellence; supreme excellence consists in breaking the enemy’s resistance without fighting.” Use the exercise to revise a concrete plan, rather than treating a reversed question as a solution by itself.