Confirmation Bias
Seeking information that confirms your existing beliefs
What is it?
Confirmation bias is one of the most widely studied cognitive biases, and it shows up in many areas of decision-making. It works through several mechanisms: selective attention (noticing information that supports our beliefs), biased interpretation (reading ambiguous information as supportive), biased memory (recalling confirming information more easily), and biased search (seeking supporting evidence while avoiding contradictory data). It is costly because it makes beliefs self-reinforcing: the more we filter, the harder they become to correct. In Peter Wason's classic 2-4-6 task, many participants tested only examples that fit their own hypothesis rather than ones that could prove it wrong. At work, confirmation bias can lead to poor hiring decisions, failed projects, and strategic errors. In personal life, it can strain relationships and keep us from changing our minds when we should. It is amplified by emotional investment in a belief and by information sources that mostly echo what we already think.
Read the full guide
What Is Confirmation Bias? How It Distorts Your Thinking and How to Overcome It
Example
In a hiring process, focusing on the strengths that match your first impression of a candidate while overlooking red flags. Reading only good news about a stock you own and dismissing warnings. Noticing every flaw in a friend's new partner once you've decided you don't like them.
References
Wason, P. C. (1960). On the Failure to Eliminate Hypotheses in a Conceptual Task. Quarterly Journal of Experimental Psychology, 12(3), 129-140.
Nickerson, R. S. (1998). Confirmation Bias: A Ubiquitous Phenomenon in Many Guises. Review of General Psychology, 2(2), 175-220.
Lord, C. G., Ross, L., & Lepper, M. R. (1979). Biased Assimilation and Attitude Polarization: The Effects of Prior Theories on Subsequently Considered Evidence. Journal of Personality and Social Psychology, 37(11), 2098-2109.
How to Prevent It
Doxa uses AI and can make mistakes. How it's built
What evidence would change my mind about this?
Am I giving equal weight to contradicting information?
Have I actively sought out disconfirming evidence?
Why might the opposing view actually be correct?
Am I interpreting ambiguous data to support my belief?
Write down the one fact that would most weaken your position, then go and check it.
Write down your decision criteria before you review the information.
Assign someone to argue the opposing position (devil's advocate).
Use a decision grid that forces you to list the cons of your preferred option.
Delay forming strong opinions until gathering diverse sources.
Scientific Sources
Related Decisions
Hiring a new team member
May focus on info that confirms first impression
Committing to a relationship
May ignore red flags that contradict hopes
Buying a home
May only notice features that confirm what you want
Making a major business investment
May seek info that supports the investment
Entering a new market
May seek data supporting market entry
Choosing a co-founder
May dismiss early warning signs to keep the partnership
Launching a product
May read early feedback as proof the product is ready