Decision Making and the Common Belief Fallacy

Some friends of ours recently bought a pet gerbil.  The kids wanted a dog, and so did the wife, but the husband’s theory was that you have to work your way up the ladder of responsibility before you bring home a family pooch.

“So you’re saying you want to voluntarily bring a rodent into our house?” she chided.

“It’s not like I bought a rat!” He answered.

He used to have a point.  For the past 800 years, rats have been getting all the bad press.  They are disease-carrying, baby-biting vermin, responsible for spreading plagues that killed over 100 million Europeans from the 14th to 18th centuries. 

Or so we thought.

A recent study published in the Proceedings of the National Academy of Sciences brings the role of rats into serious doubt.  By studying climate records and tree-ring data, they found that the environmental conditions that coincide with the plagues are terrible for rats, making it virtually impossible for them to spread disease to an entire continent.  However, those same conditions are extremely favorable for another species.

The gerbil.

As textbook makers quickly assemble to rewrite history, and parents across the country take little Snowball on a trip to “live on a farm,” the rest of us are left wondering where else we might be falling victim to the Common Belief Fallacy – accepting something as true because most people believe it is so.  Such thinking is not only damaging to our health, but can threaten the success of our decision making as well.  Here’s how to avoid it.

  1. Experiment – Organizations are inherently risk-averse, so they often dismiss new, potentially groundbreaking ideas just because many people say they will not work.  Instead of accepting this belief, see if it might be feasible to run a limited-risk trial before finalizing a decision.  There’s a saying in marketing circles – “test everything”- and we need to adopt this in other places as well.
  2. Reexamine Your Pillars – The foundation of your business (your target market, your cash cow, your competitive advantage) rarely gets questioned.  But while a beachfront condo may be built on solid piers, shifting sand could cause the whole thing to topple.  Identify what leading indicators in your market or industry would necessitate a major strategic shift, and plan accordingly.
  3. Seek Contrary Evidence – It is easy to find data to support our decisions and conclusions.  However, we tend to easily dismiss data that contradicts our preconceived decision as an anomaly and unimportant.  As illustrated in this clip from Paramount Pictures movie, World War Z, we should assign someone to actively seek out contrary evidence before acting on a decision that “everyone” thinks is the right way to go.

At Action Management, we have been helping clients improve their critical thinking for nearly forty years.  If you and your organization would like to rethink your own rodents, we have proven tools and techniques.  Just give us a call at 800-386-5611.  We would love to help you improve on your successes! 
















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