Our interpretations of the world can often be wrong due to bias, optimism, pessimism, or bad information. Yet most of us think we are right and other people are wrong. This can cause us to overlook or dismiss crucial information and lead to bad decisions.

In 1847, Ignaz Semmelweis proposed doctors wash their hands before delivering babies in obstetric clinics to reduce the spread of “childbed fever,”  a common and often fatal disease in hospitals in the mid-19th century. A doctor and a scientist, Semmelweis had noticed that two clinics had a significant difference in mortality rates for women giving birth. The two facilities used similar techniques, but one clinic taught medical students, who also performed autopsies, and those students did not wash their hands before going to the maternity ward to help a woman give birth.

 The second clinic taught midwives and did not engage in autopsies, so the students  had no contact with corpses. The clinic educating doctors had a mortality rate of 10%, and the clinic educating midwives had a mortality rate of 4%. Women begged to give birth in the clinic with the midwives and would even give birth in the streets to avoid the clinic with the  student doctors.

Although Semmelweis published results showing that the mortality rate for mothers dropped below 1% when medical staff engaged in proper handwashing, his observations conflicted with what the scientific and medical establishment believed at the time. Doctors were offended by the idea that they should wash their hands and mocked him. Semmelweis ended up having a nervous breakdown because no one would accept his findings. He was committed to a mental asylum and died 14 days later, at the age of 47. Cause of death was gangrene from a wound he received when he was beaten by the guards. 

The blind certainty of the doctors in Semmelweis’s day caused people to die. It took us 150,000 years to figure out that washing our hands prevents the spread of disease. In evolutionary timescale, this is the equivalent of yesterday, and a lot of lives were needlessly lost in those years. 

Our veil of ignorance prevents us from seeing reality accurately. I’ve noticed that the top experts in a field often admit  that there is a lot they don’t  know or understand. The more you know about something, the more likely you are to see how much you don’t know. We don’t even understand consciousness or how our own brains work, and we have barely begun exploring the oceans or outer space. To say we have blind spots is a big understatement.

Fooling Ourselves

The easiest person to fool is yourself. As you get older, you realize how  wrong you  were in the past. Most of the  beliefs I held most deeply in my twenties and thirties were wrong. In fact, it would be an easier exercise to identify what I was right about than to try to count all the ways I was wrong. I see the error of my past ways more clearly now because I’ve learned more, seen more, and thought more. Exposing yourself to different viewpoints and engaging in a little bit of self-reflection can reveal how easy it is to trick yourself. 

It’s very difficult to convince yourself of a new idea when a contradictory idea is already anchored in your thinking. When you understand that this blind spot is our normal state, you can  design decision-making processes to overcome it — which can help you avoid painful mistakes and give you an unfair advantage. But this effort takes humility and can be difficult. 

Here are a few ways I’ve found to improve my judgment and be wrong less often.

• Invest time to learn principles and mental models. A mental model is an idea that helps you better understand the reality of the world around you. They teach us how to think better  and provide shortcuts to higher-level thinking by forcing your brain to think about a problem or decision from different perspectives. Examples include thinking gray, inversion, Eisenhower decision matrix, and thinking from first principles.
• Surround yourself with people who have diverse viewpoints and think differently from you. This will help you see problems from different angles and develop creative solutions. Most of us don’t do this because we are more comfortable being around people who think like we do. 
• Ask for feedback often from customers, advisors, and employees. Feedback helps you better see the reality of the world around you. It allows you to correct mistakes and learn faster. Feedback gives you an opportunity to gain empathy by seeing different perspectives, and it shines a bright light on your blind spots, improving your decision-making ability.  

Don’t fool yourself. Apply these ideas to see reality more clearly, improve your judgement, and be wrong less often.