O perigo do viés de confirmação e das certezas absolutas

Robert Burton em entrevista à Scientific American:

BURTON: A personal confession: I have always been puzzled by those who seem utterly confident in their knowledge. Perhaps this is a constitutional defect on my part, but I seldom have the sense of knowing unequivocally that I am right. Consequently I have looked upon those who ooze self-confidence and certainty with a combination of envy and suspicion. At a professional level, I have long wondered why so many physicians will recommend unproven, even risky therapies simply because they “know” that these treatments work.


LEHRER: To what extent do these mechanisms come into play during a presidential election? It seems like we all turn into such partisan hacks every four years, completely certain that our side is right.

BURTON: The present presidential debates and associated media commentary feel like laboratory confirmation that the involuntary feeling of certainty plays a greater role in decision-making than conscious contemplation and reason.

I suspect that retreat into absolute ideologies is accentuated during periods of confusion, lack of governmental direction, economic chaos and information overload. At bottom, we are pattern recognizers who seek escape from ambiguity and indecision. If a major brain function is to maintain mental homeostasis, it is understandable how stances of certainty can counteract anxiety and apprehension. Even though I know better, I find myself somewhat reassured (albeit temporarily) by absolute comments such as, “the stock market always recovers,” even when I realize that this may be only wishful thinking.

Sadly, my cynical side also suspects that political advisors use this knowledge of the biology of certainty to actively manipulate public opinion. Nuance is abandoned in favor of absolutes.

LEHRER: How can people avoid the certainty bias?

BURTON: I don’t believe that we can avoid certainty bias, but we can mitigate its effect by becoming aware of how our mind assesses itself. As you may know from my book, I’ve taken strong exception to the popular notion that we can rely upon hunches and gut feelings as though they reflect the accuracy of a thought.

My hope is the converse; we need to recognize that the feelings of certainty and conviction are involuntary mental sensations, not logical conclusions. Intuitions, gut feelings and hunches are neither right nor wrong but tentative ideas that must then be submitted to empirical testing. If such testing isn’t possible (such as in deciding whether or not to pull out of Iraq), then we must accept that any absolute stance is merely a personal vision, not a statement of fact.

Perhaps one of my favorite examples of how certainty is often misleading is the great mathematician Srinivasava Ramanujan. At his death, his notebook was filled with theorems that he was certain were correct. Some were subsequently proven correct; others turned out to be dead wrong. Ramanujan’s lines of reasoning lead to correct and incorrect answers, but he couldn’t tell the difference. Only the resultant theorems were testable.

In short, please run, do not walk, to the nearest exit when you hear so-called leaders being certain of any particular policy. Only in the absence of certainty can we have open-mindedness, mental flexibility and willingness to contemplate alternative ideas.