The Confirmation Bias - Why Self-Justification is Just So Easy

“Sleep?! Sleep is for people who are broke. I don’t sleep. I have an opportunity to turn a dream into a reality.” – Curtis '50 Cent' Jackson

I think about that quote every time I am up late working. When I realize that I have to make a decision - sleep? or work? I know the extraordinary value that sleep has on my willpower, but when I want to keep working, I just think about that quote.

Then I automatically turn to other stories of great people who "don't need" a full night of sleep. 

Arnold Schwarzenegger famously said to a group of graduating seniors, “you only need 6 hours of sleep. If you feel like you need more, then sleep faster!” [1]

Leornardo da Vinci spent even fewer hours sleeping per day by only taking a 20-minute nap every 4 hours – a total of only 2 hours/day! [2]

Even successful CEOs like Marissa Mayer of Yahoo report only sleeping a mere 4 hours per night. [3]

Yet, the science on how sleep’s affects your willpower is clear – if you do not get enough sleep, your overall energy, intelligence, and productivity, will all suffer. [4]

So how do I decide?

Do I follow the lead of the successful people listed and disregard sleep?

Or do I follow the clear scientific evidence and stick to my regular sleeping plan?

It all depends on which answer I want to be confirmed.


If I really want to stay up late working and disregard sleep, I will use the anecdotal evidence of Marissa Mayer, Leonardo da Vinci and Arnold Schwarzenegger to justify my decision to continue working.

However, if I’m tired, if I’m burned out and I really do not want to continue working, then I will use the scientific evidence to justify my decision to go to sleep.

No matter what I’m feeling, I will naturally search for self-justifying information. This is called the confirmation bias and it is one of the key reasons that you make bad decisions on the way to your goals. [4]

The confirmation bias is when you – knowingly or unknowingly – search for information that will justify the decision that you want to make - rather than the best one.

Someone who wants to skip their workout will search for information on the benefits of taking time to rest and recover.

Someone on a diet who wants to indulge in their favorite treat will begin to look up the benefits of a "cheat day".

And a hiring manager who really likes a candidate after their first interview will probably start downplaying any flaws in their second interview.

Although they may think that they’re gathering more information to make an informed decision, they are really just seeking to confirm their current bias.


The problem with the confirmation bias is not that we are looking up incorrect information. It is a fact that rest and recovery is necessary in an exercise routine. It is a fact that Leonardo da Vinci only slept for 4 hours each day and that there is value in having a “cheat day”.

The danger comes when we are only looking for this confirming information and completely ignoring the opposing view.

So we do a google search “is it okay to have a cheat day?”

Then skim through the first article and immediately start looking for the benefits. Then convince ourselves that the benefits are more applicable to our unique situation anyway. So we really should go ahead and have a cheat day.

Now, although we feel like we have done further research, all we have really done is simply look up confirming information of what we really want. We see only what we want to see and use it as justification for deviating from our plans.

Then, eventually, we look up so much confirming information that we deviate from our goals entirely.


It is not easy to defeat the confirmation bias. After all, we legitimately think that we're doing the proper research! But, of course, it can be done with a little willpower and self-awareness. 

In their book, Decisive, brothers Dan and Chip Heath write extensively on the subject of the confirmation bias and how you can overcome it. Here are 3 ways that you can overcome the confirmation bias and stay on track toward your goals:


If you can gain the self-awareness to realize that you are biased toward one particular side of a decision, summon the willpower to consider the opposite with an open mind.  

If you are thinking about hiring a particular candidate, force yourself to consider all of the reasons NOT to hire him or her. List all of the reasons he or she would not be a good candidate and take the list seriously.

If you are thinking about taking a day off from the gym, look up all of the reasons that it is good to be consistent n your exercise routine – such as habit formation.

You will still have a bias, of course. However, willing yourself to go through the process of considering the opposite will at least allow you to see the opposing view. This is not perfect, but it is better than ignoring it entirely. 


Whenever an entrepreneur starts a new business she is taking a big risk. She is going against money, security and the odds of success. Most business fail within the first 5 years. And many who make it beyond that fail in the next 5 years.

Of course, many entrepreneurs decide to ignore these stats because they believe that they will be one of the less than 10% of successful companies out there. They have to believe this - otherwise new businesses would never get started! However, many entrepreneurs choose to completely ignore the statistics.

They say, “well, none of those people know this product or market like I do!”

They disregard the risks, rather than respect them, research why those companies failed, and learn what they can do differently. This is not bold or admirable; it’s merely egotistical – believing that they have some divine gift that 90% of others do not.

And it is not just risk-seeking entrepreneurs who ignore statistics. Usually, we do not even respect the data on ourselves! Rather than look back at the goals we have failed in the past, learn from our mistakes and make smart changes, we simply rely on newfound willpower to persevere.

"This time is going to be different!"

Do not get caught in this trap. Force yourself to look at the objective data – whether on others or yourself. Whatever your goal is, look at the average success rate as well as your personal success rate. 

Then learn from the past and use it to set yourself up for a successful future.


Every year, thousands of soon-to-be college graduates sign up to work long hours for no pay in an internship. This is often thought of as a complete abuse of the system by corporations – and there are certainly some that do – but overall many internships are worth it to the college student. 

Not only do they get a foot in the door and gain some experience, they also get an opportunity to see if this career path is really for them. This allows them to experiment with their career before making a final decision.

If you’re looking to get into medical school, isn’t it worth it to take an internship at a local hospital before spending 10 years and hundreds of thousands of dollars on education?

If you want to hire someone, isn't it worth it to have them do a smaller project before you both invest lots of time and energy into training, team-building and larger projects?

If you’re looking to have a cheat day, isn’t it worth it to experience how much extra time in the gym you’ll have to spend to make up for those calories?

The more you can experiment with the decision before fully jumping in, the less biased you will be. 

Despite the money and prestige, the day-to-day work of a doctor may not be worth it to you. And the extra time you have to spend in the gym may not be worth that cheat day.  


Most of us are smart enough to seek out more information in order to make a well-informed decision. The problems occur when we aren’t really seeking information, we’re just seeking justification for what we really want.

If you want to quit your job and follow your passion, you’ll find confirming stories of people who have done so with wild success. If you want to stay in the 9-5 world, you’ll find information that says that it is stupid to quit your secure job and take a chance.

The next time you feel tempted to justify a decision that you really want, stop. Summon the willpower to consider the opposite, respect the objective data and experiment before you make a final decision. You will be much happier with your actual well-informed decision!


  1. Arnold Schwarzenegger: Life's 6 Rules - FULL SPEECH. (2009) from
  2. Giang, V. (2013, November 19). 11 Bizarre Sleeping Habits Of Highly Successful People from
  3. Nisen, C. (2012, September 18). 19 Successful People Who Barely Sleep. Retrieved from
  4. Heath, C., & Heath, D. (2013). Decisive. New York: Crown Business.