Jumping to Conclusions

People tend to jump to conclusions. Not just other people, but most of us, as the authors of The Invisible Gorilla explain. There are several reasons for this.

 

First, it’s got to do with how we are wired:

“We perceive patterns where none exist, and we misperceive them when they do exist.”

To compound the problem, we are prone to the “illusion of cause”:

“(We are) biased to perceive meaning rather than randomness and to infer cause than coincidence.”

 

A related aspect is that we tend to confuse correlation with causation. In simpler terms, just because two things happen together doesn’t mean one causes the other. The best example of this danger is the ice cream-drowning example:

“More people drown on days when a lot of ice cream is consumed, and fewer people tend to drown when only a little ice cream is consumed.”

This example, of course, is so obvious that nobody would claim that the consumption of ice cream causes drowning. And it’s obvious to most that the underlying connection is heat (If it’s hot, people eat more ice cream and more people go swimming, which increases drowning incidents). Unfortunately:

“Seeing through the illusion of cause is rarely so simple in real life.”

 

Further, we love simplified explanations. Complexity is so exhausting. Much easier to believe there’s one reason for events: greed, incompetence, whatever. A chronological narrative is so satisfying at an emotional level.

 

But how about those cases where a huge number of people buy into seeming nonsense? Yes, other factors matter when it comes to groups:

“It needs a credible authority to validate the causal link.”

They cite the example of why so many in the US and UK are averse to vaccinating their children against measles. A prominent London physician, Dr. Andrew Wakefield, announced a link between the measles vaccine and autism in 1998. He pointed at several “articulate, well-educated” parents whose children had this side-effect. See how respectable (and thus credible) it sounded?

 

Next, the anti-vaccine idea benefited from another human tendency:

“Personal anecdotes are more memorable and stick in our minds much longer than abstract data.”

As always, this tendency can be linked to good old evolution:

“Our brains evolved under conditions in which the only evidence available to us was what we experienced ourselves and what we heard from trusted others. Our ancestors lacked access to huge data sets, statistics, and experimental methods.”

 

That last part also explains why “overcoming anecdotes with science and statistics” is so hard, even impossible at times.