Assumptions are everywhere: they are the foundation of everything we think, say and do. Like the air we breathe, they are invisible and necessary. They save time by allowing us to take certain facts and situations for granted and let us get on with the business of forming and exchanging new ideas.
However, because they remain out of sight and out of mind, we usually don’t realize how many assumptions we take for granted when we make decisions. When our assumptions are wrong, we can commit major errors. When the stakes are high, or when things are rapidly changing, it helps to have a mental tool-kit that allows us to examine our own—and others’—assumptions.
Here’s a list of 10 assumptions that can lead us astray. I’ve borrowed the list from a course I teach, Precision Questioning and Answering by Vervago, but the examples, prioritization and editorial comments are my own. I’ve listed them in order of frequency, but don’t assume the order is anything other than totally subjective.
Similarity: Assuming that the situation is similar to something we’ve seen before. I put this one first because the hallmark of learning from experience is that you have a rich store of situations that you can draw on when you face a new situation. It works well as long as the new situation is identical in the relevant factors. When it’s not, that’s when we get into trouble, and with the pace of change we face today, there are going to be many times when the new situation is fundamentally different. Armies prepare diligently to fight the past war. The similarity assumption almost killed a friend of mine when doctors kept prescribing more antibiotics for a “sinus infection” which was only a symptom for a rare and serious disease.
Category: Assuming that things are properly grouped together, or that a thing shares all the characteristics of its category. For example, we assume all Republicans and all Democrats will think or behave a certain way. Our own categories can also influence our assumptions: if sales are flat, marketers assume it’s a marketing problem, engineers see it as an engineering problem, economists assume it has to do with the economy, etc.
Uniqueness: Assuming that there is only one of something. This leads to oversimplification and a “Whack-A-Mole” approach to problems: you fix one issue and another pops up. This one’s easy to spot: When someone says “the problem is…, or the solution is…”, you potentially have a uniqueness assumption.
Possibility: Assuming something is possible. Bankers who bought risky loans assumed they would be able to sell them if they got into trouble.
Impossibility: Assuming something is impossible, and ignoring Black Swan events in your planning, such as a 9.0 scale earthquake and a 30 foot tsunami when designing a nuclear power plant. While this one may be considered merely a version of the possibility assumption, it helps to shift your questiong perspective.
Audience: Assuming that all participants have a common view or understanding. Our leaders assumed that Iraqis would welcome us with open arms and gratitude because we freed them from a brutal dictator. In 1999, the Mars Climate Orbiter mission failed, costing $125 million, because Lockheed Martin engineers used English units in navigation information and handed it off to NASA, which assumed they were metric units.
Time and Constancy: Assuming that things remain constant over time. This assumption commonly occurs when we take too long to respond to a situation. Borrowers who took mortgages knowing their interest rate would balloon, because they assumed prices would go up and they could refinance. This assumption is most likely to crop up during volatile and unstable times.
Value: Assuming that something is either good or bad, problem or opportunity. Most of us assumed that the democracy movement in Egypt was a good thing, and now the assumption that the Muslim Brotherhood may dominate the first free elections is seen (to Westerners—I have to avoid the audience assumption) as a bad thing. The value assumption is one can turn into a self-fulfilling prophecy, and become true merely because we think it is.
Existence: Assuming something exists. We see this assumption in the press all the time, when isolated but vivid incidents lead to a common perception that a serious problem exists that must be stamped out. Marketers make this assumption error all the time, presuming demand exists
Measurement: Assuming something can be measured, or that measurement won’t change the value. When I would take the Jetta in to the dealership, the service manager would tell me that if the survey I received in the mail about the service experience did not reflect all “excellents” he could lose his job. I wonder if someone at VW headquarters really believes in their results? It’s also a common problem in polling, when respondents tell questioners what they think they want to hear.
Pattern: Assuming a pattern where none exists. This assumption is not one on Vervago’s list, but I include it here because it’s completely natural for people to try to connect the dots and find patterns, but sometimes the dots are simply unconnectable and coincidental. According to Gary Klein, who studies expert decision making, experts’ intution is actually the ability to instantly recognize patterns. This works well in most cases, but some situations are new and unique.
As you can see from this list, there is a lot under the surface of any communication or situation. In fact, probably the only thing you can safely assume is that at least one of your assumptions is bound to be flawed!