Confirmation bias

Also known as the myside bias · Belief formation

Confirmation bias is the tendency to seek, interpret, and remember information that confirms what you already believe, while discounting evidence that contradicts it — making beliefs feel better justified than the evidence actually warrants.

Foundational — cross-referenced 37× across this reference (20 related ideas · 3 comparisons · 12 hubs · 1 book) · The State of Thinking 2026 →

By the ReadGlobe Editors · Reviewed 2026-05-29

Why it happens

The mind is a cognitive miser, and beliefs are bound up with identity. Disconfirming evidence is both effortful to process and threatening to the self, so attention drifts toward agreement. We ask questions whose answers will confirm, and we judge supporting evidence less critically than opposing evidence.


It only loses to rules set in advance: pre-commit to what evidence would change your mind.

Examples

  • Choosing news sources that echo your existing politics and dismissing the rest as biased.
  • Googling a symptom and clicking only the results that match the diagnosis you already fear.
  • An investor who owns a stock reading only the bullish analysis and skipping the bearish case.

How to counter it


  • Actively build the strongest version of the opposing argument (steelman it) before judging.
  • Ask in advance: “What specific evidence would change my mind?” — then go look for it.
  • Write predictions down so you can’t quietly rewrite what you believed.

The deeper point

The cure isn’t "be more objective" — nobody believes they’re biased. It’s procedural: pre-commit to what evidence would change your mind before you see any. Confirmation bias only loses to rules set in advance.

Frequently asked


What is a simple example of confirmation bias?
Believing a coin is “lucky,” then remembering the times it won and forgetting the times it lost — so the belief feels confirmed by a memory you unconsciously filtered.
How do you overcome confirmation bias?
Deliberately seek disconfirming evidence, steelman the opposing view, and decide in advance what would change your mind. Writing predictions down stops hindsight from rewriting them.
Is confirmation bias the same as cognitive dissonance?
No. Confirmation bias is how you filter incoming evidence; cognitive dissonance is the discomfort of holding conflicting beliefs. Confirmation bias is often a strategy for avoiding that dissonance.

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Where it’s shows up in

See this alongside the other thinking tools of investing, building a startup, product management, persuasion & marketing, writing clearly and hiring.

Where it bites

This bias distorts investing, hiring, meetings, performance reviews, product decisions and studying & learning.

Go deeper


The book behind this idea: Thinking, Fast and Slow by Daniel Kahneman. Hear the whole thing free — start an Audible trial and your first audiobook is on the house.

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APA

ReadGlobe. (2026). Confirmation bias. https://readglobe.com/bias/confirmation-bias/

MLA

"Confirmation bias." ReadGlobe, 29 May 2026, readglobe.com/bias/confirmation-bias/.

Primary source: Wikipedia

Editorial synthesis © ReadGlobe 2026, drawing on Kahneman’s Thinking, Fast and Slow, the Tversky–Kahneman research program, and the primary cognitive-science literature. · Last reviewed 2026-05-29.