THINKER'S ALMANAC - April 21

What can the confirmation of a U.S. Supreme Court Nominee in 1991 teach about our tendency to perceive past events as more predictable than they actually were?

Subject: Hindsight Bias - Clarence Thomas's Nomination to the Supreme Court

Event:  The pioneer researcher in hindsight bias Baruch Fischhoff is born, 1946.

Take a moment to contemplate the following question:

How can you drop an egg onto a concrete floor without cracking it?  

The answer is “very easily because an egg will not crack a concrete floor.”

Now that you know the answer, does it seem like you actually knew it all along?  There’s an old saying that “hindsight is 20/20,” which means that people tend to view events as more predictable after the fact than they were before they happened.  

In the 1970s, Baruch Fischhoff, who was born on this day in 1946, was a student working on his master's degree in psychology.  While attending a lecture by Paul E. Meehl, Fischhoff noted a comment that Meehl made about the fact that psychiatric clinicians often overestimate their ability to predict outcomes.  Fischhoff seized on the seemingly off-the-cuff comment, using it as the inspiration for the first studies in hindsight bias.

Since Fischhoff published his first studies in the 1970s, many others have confirmed the impact of hindsight bias.  One study, for example, involved college students' predictions about the U.S. Senate’s confirmation vote for Supreme Court nominee Clarence Thomas in 1991.  Before the vote, 58% of the students predicted that Thomas would be confirmed.  Later, after Thomas was confirmed and the same students were polled again, 78% said they had thought that Thomas would be confirmed.

Hindsight bias is a close cousin to another cognitive bias, confirmation bias.  With confirmation bias, we begin with a conclusion and then put on blinders to anything other than evidence that supports our conclusion (see THINKER’S ALMANAC - February 15).  Hindsight bias reverses this process.  We begin with factual evidence of an event from the past - such as who won this year’s Super Bowl -- and we then revise our judgments about what happened, giving ourselves credit for foreseeing what happened as inevitable.

This tendency to tell ourselves that “I knew it all along” makes sense when you think about how our brains work.  As psychologist Kathleen A. Vohs explains, it's much easier to tell ourselves a story about what happened in the past than it is to process information in real-time:  

What consciousness does is tell the most compelling story it can come up with. That means to tell a neat story, where all the pieces fit together. This means that the past becomes a lot more ‘knowable’ than it was in reality, and hence hindsight bias. (1)

The best way to counteract the hindsight bias is to consciously consider multiple possibilities prior to a final outcome.  For example, in one study a group of psychiatrists was asked to rate the probability of different diagnoses after studying the background of a patient.  The doctors who were asked to explain the reasoning behind each of the possible diagnoses were significantly less likely to demonstrate hindsight bias than the doctors who rated the diagnoses without providing any rationales.

Recall, Retrieve, Recite, Ruminate, Reflect, Reason:  What is hindsight bias, and how does it relate to confirmation bias?

Challenge - Did You Know It All Along? : Consider a historic event that has happened in your lifetime on a single day.  Looking back at what happened on that day, does it now seem inevitable?  Reflect on how you view it now and whether or not you think hindsight bias is playing a part in how you perceive the event today.

Sources:

1-Carey, Benedict. “That Guy Won? Why We Knew It All Along.”  The New York Times 30 Oct. 2012.