Sherlock Holmes' Top 10 Lessons for Problem Solvers
Problem solving is detective work. The search for the root causes of a problem is very much like the search for the perpetrator of a crime, so Sherlock Holmes' perspective is insightful. Holmes' Top 10 Tips are excerpts from The Complete Sherlock Holmes by Sir Arthur Conan Doyle. They provide the framework for an effective investigation.
- Tip 1 - "In solving a problem of this sort, the grand thing is to be able to reason backwards. That is a very useful accomplishment, and a very easy one, but people do not practice it much. In the everyday affairs of life, it is more useful to reason forwards, and so the other comes to be neglected. There are fifty who can reason synthetically for one who can reason analytically."
- Tip 2 - "Always approach a case with an absolutely blank mind. Form no theories, just simply observe and draw inferences from your observations." and "It is a capital mistake to theorize before one has data. Insensibly one begins to twist facts to suit theories, instead of theories to suit facts."
- Tip 3 - "How dangerous it is to reason from insufficient data." and "Data, Data, Data! I can't make bricks without clay."
- Tip 4 - "Detection is, or ought to be, an exact science, and should be treated in the same cold unemotional manner. When you attempt to tinge it with romanticism, you produce the same effect as if you worked a love-story into the fifth proposition of Euclid."
- Tip 5 - "It is of the highest importance in the art of detection to be able to recognize out of a number of facts which are incidental and which are vital."
- Tip 6 - "I can see nothing," said Watson, handing it back to Holmes. "On the contrary, Watson, you can see everything. You fail, however, to reason from what you see. You are too timid in drawing your inferences."
- Tip 7 - "I never guess. It is a shocking habit -- destructive to the logical faculty."
- State the Problem
- Conduct Research
- Formulate Hypotheses
- Test the Hypotheses
- Confirm Hypotheses or Formulate New Hypotheses
- Tip 8 - "Nothing clears up a case so much as stating it to another person."
- Tip 9 - "Once you eliminate the impossible, whatever remains, no matter how improbable, must be the truth."
- Tip 10 - "You know my methods. Apply them."
This quotation is the fundamental concept all effective problem solvers use. Everything derives from it.
Synthetic thought, the way we live life everyday, uses divergent thinking. It flows from cause to effect. It generates a variety of possible options, and then decides which one or ones to pursue. During problem solving, synthetic thinking is only appropriate when developing possible solutions to implement, after the searcher has identified the root causes. Synthetic thinking is inappropriate when searching for root causes because the root causes already exist and simply need to be discovered. Synthetic divergent thinking is ineffective for finding root causes because it guesses about them rather than systematically searching for them.
Analytical thought, reasoning backwards, is convergent thinking. It proceeds from effect to cause. It is the superior approach for identifying root causes because it quickly leads to complete solutions. Analytical thinkers systematically look for clues that will reveal the root causes. They use observation followed by deduction, the same technique used by Holmes. This approach has helped thousands of people to become effective problem solvers.
These comments highlight the critical weakness of synthetic, forwards reasoning when solving problems. Investigators guess first, and then test their guesses, rather than simply observing and letting the situation reveal itself. Save all hypothesizing for identifying possible solutions after the root causes have been identified using analytical, backwards reasoning.
These comments elaborate on Tip 2. Observe carefully. Deduce carefully. Make sure your conclusions do not overreach your data.
Tips 1 and 2 cautioned against speculation or guesswork when approaching a problem. Tip 4 goes a step further, cautioning against the introduction of emotion into the deduction process as well. It is easy, even natural, to let feelings get involved. Resist this temptation. Simply let the data reveal the answer.
Invariably there are dozens, hundreds, or even thousands of possible causes for any problem, but just as certainly, no more than three factors are responsible for 90-100% of the problem. The most effective problem solvers use Holmes' "observation, deduction, knowledge" strategy and a few simple tools to eliminate the incidental and unimportant factors from the vital few.
This tip is the extension of Tip 3 to its natural conclusion. Tip 3 guides the investigator to always have adequate data to draw sound conclusions. Tip 6 challenges the investigator to use the data wisely and reason through the problem completely. A few simple tools make this a straightforward process.
Hypotheses, theories, and guesses are never part of effective problem solving. (They are useful in deciding on possible solutions, but only after the cause has been identified.) It might seem on the surface that Holmes' rejection of theory formation (i.e., hypotheses) is in conflict with the Scientific Method, but it isn't. The basic outline of the Scientific Method is:
Divergent thinkers spend too little time conducting research before starting to formulate hypotheses about the root causes. These investigators develop an exhaustive list of possibilities, all of which require testing. By shortening or omitting the research step and immediately formulating dozens or hundreds of root cause hypotheses to test, today’s most common problem solving processes have strayed from the Scientific Method. The greater the number of hypotheses that must be tested, the longer it takes to find the first root cause, and the lower is the probability that an investigator will find all the root causes.
Holmes' convergent method of reasoning backwards focuses on conducting research, making observations, and gathering data from the situation. Holmes' deductions, based on his observations, are his hypotheses. His theories always fit the facts he has observed without any bias. Holmes' "Observe, then Deduce" methodology is the approach that remains true to the Scientific Method.
Writing straightens thinking, and thinking straightens writing. Presenting a summary of the situation to another person, whether verbally or on paper, requires the investigator to consolidate all the data, which leads to additional insight and better understanding.
This most famous tip from all the Sherlock Holmes’ stories perhaps best summarizes effective problem solving. Observe the situation. Look for patterns and consistent differences between the best performance and the worst performance. Eliminate any factor that is not consistently different. Any factors that remain, factors that are consistently different when a problem exists and when it doesn't, must be critical.
Holmes' caveat "no matter how improbable" is common in effective problem solving. The most critical root cause in most problems is often, even usually, something no one has ever suspected. No amount of hypothesizing root causes would ever have come up with it as a factor. This is the primary reason to "observe with an absolutely blank mind" and never to guess.
Observation, Deduction, Knowledge. Never guess. The natural tendency for most people is to brainstorm. Effective problem solvers resist this temptation. Apply Holmes' simple strategy to dramatically improve your problem solving skills. Observe what's different when the problem occurs, and when it doesn't. Look for consistent differences. Any factor that is not consistently different is not involved in the problem. Ignore it. Anything that is consistently different is involved in the problem in some way. It is a clue – pursue it. Use the clues to deduce the root cause or causes of the problem.
If you are in business, Young Associates can help you apply Holmes' proven approach by introducing hands-on tools based on his reasoning backwards strategy, tools that have worked for hundreds of companies worldwide. We can address a single project for you, or we can train and coach your people to master these techniques. We will also help you internalize the training when you feel it is appropriate. Our book, Reasoning Backwards: Sherlock Holmes' Guide to Effective Problem Solving teaches all these techniques and is a handy desk reference for all your employees that enables everyone to become an effective problem solver.
If your interest is education and teaching students how to be effective problem solvers before they leave school, then Reasoning Backwards: Sherlock Holmes' Guide to Effective Problem Solving provides students with strategies that will help them score better on standardized tests now, and will serve as a handy desk reference of problem solving techniques when they enter the workplace. Young Associates wants to for partnerships with corporations, foundations, schools, and non-profits that will introduce problem solving best practices to students and will benefit all involved. To explore partnership possibilities, please contact Young Associates at (989) 492-2029 or by email at firstname.lastname@example.org.
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