Master Your Thinking
190+ Cognitive Biases in 66 Languages
Master Your Thinking
See reality more clearly and make better decisions. Explore 190+ cognitive biases to understand why the mind misjudges, and what you can do about it.
A free social-impact project in 66 languages, with one target: a billion people who can catch their own thinking going wrong.
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What is a cognitive bias?
A cognitive bias is a systematic error in thinking: a mental shortcut that helped our ancestors decide fast and now quietly distorts everyday judgment. This library covers 190+ of them in plain language — where each one comes from, and how to catch it in yourself.
Every entry ends with its primary sources. That comes to more than 1,800 academic references across the 190 articles.
Reviewed by Volodymyr Zhukov
Last reviewed August 2026
The 10% Rule
It only takes 10% of us.
In 2011, researchers at Rensselaer Polytechnic Institute's Social Cognitive Networks Academic Research Center modelled how an idea travels through a network. Under 10% committed believers it stalls — reaching the majority would take longer than the universe has existed. Cross 10% and the majority follows fast.
Apply that to how we think. If one person in ten can name a cognitive bias out loud and refuses to make decisions on one, the other nine adjust. Not because anyone argued them into it, but because sloppy reasoning stops going unchallenged.
So that is the plan. One billion people through a free course on how the mind misjudges. We are heading the other way at the moment: confidence keeps outrunning knowledge, and most people have never been told their brain misfires by design. Ten percent is what turns that around.
Be part of the 10% → Learn more →
Ten people in a hundred. That is the whole threshold: past it, a way of thinking stops being a minority position and becomes the default.
10% of a population is the tipping point for an unshakable belief Xie et al., Physical Review E, 2011
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66 languages, and every article is free to read
Categories
Bias Categories
Browse biases by category to understand different aspects of human decision making.
Or see the full list of all cognitive biases →
01 Too much information 5 patterns
- We notice things already primed in memory or repeated often
- Bizarre, funny, visually-striking, or anthropomorphic things stick out more
- We notice when something has changed
- We are drawn to details that confirm our existing beliefs
- We notice flaws in others more easily than flaws in ourselves
- We find stories and patterns even in sparse data
- We fill in characteristics from stereotypes, generalities, and prior histories
- We imagine things and people we're familiar with or fond of as better
- We simplify probabilities and numbers to make them easier to think about
- We think we know what other people are thinking
- We project our current mindset and assumptions onto the past and future
- To act, we must be confident we can make an impact and feel what we do is important
- To stay focused, we favor the immediate, relatable thing in front of us
- To get things done, we tend to complete things we've invested time and energy in
- To avoid mistakes, we aim to preserve autonomy and group status, and avoid irreversible decisions
- We store memories differently based on how they were experienced
- We reduce events and lists to their key elements
- We discard specifics to form generalities
- We edit and reinforce some memories after the fact
- We favor simple-looking options and complete information over complex, ambiguous options
02 Not enough meaning 6 patterns
03 Need to act fast 4 patterns
04 What should we remember? 5 patterns