The Confirmation Bias

The tendency to seek evidence that agrees with our position and dismiss evidence that does not.

Instinctively, most humans avoid evidence that contradicts their opinions. Contrary information is upsetting and confusing. We don't want to admit our beliefs may be wrong. Admitting to thinking errors feels like a put down. Wallowing in self-righteousness feels warm and fuzzy. The Confirmation Bias is so powerful that even when we understand it deeply and witness our intransigence, we find it hard to correct.

Michael Shermer, author of The Mind of the Market, says: "Confirmation bias is where we look for and find confirmatory evidence for what we already believe and ignore disconfirmatory evidence."

Lewis Wolpert, author of Six Impossible Things before Breakfast, says: "Beliefs, once acquired, have a kind of inertia in that there is a preference to alter them as little as possible.  There is a tendency to reject evidence or ideas that are inconsistent with our beliefs." (page 85)

The Confirmation Bias sways us to...
•  favor evidence that agrees with our position
•  believe the future will bring new evidence to support it
•  cling stubbornly and passionately to our stance
•  adopt positions from traditions, religions and ideologies

Synonyms:  The Semmelweis Effect, the belief bias, belief preservation, biased assimilation, belief overkill, hypothesis locking, polarization effect, the Tolstoy syndrome, selective thinking, myside bias, law of fives, and Morton's demon.

We all seem convinced we're right about politics, religion or science these days. What makes us so sure of ourselves.  

By Robert Burton, author of  ON BEING CERTAIN