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200 cognitive biases rule our everyday thinking
Almost 200 cognitive biases rule our everyday thinking. A new codex boils them down to 4.

- Nearly 200 cognitive biases affect our decision-making.
- The sheer amount of biases should teach us humility.
- And we should recognize the essential role they play in life, as well.
Aside from mythical spiritual figures and biblical kings, humans are not objective in how they react to the world. As much as we would like to be fair and impartial about how we deal with the situations that arise on a daily basis, we process them through a complex series of internal biases before deciding how to react. Even the most self-conscious of us cannot escape the full spectrum of internal prejudices.
Brain biases can quickly become a hall of mirrors. How you understand and retain knowledge about cognitive shortcuts will determine what, if any, benefits you can derive from the substantial psychological science that's been done around them. Here we take a look at different ways of understanding cognitive biases, and different approaches to learning from them. Enjoy!
The Peter Baumann approach

Originally a pioneer of German electronic dance music, Peter Baumann now devotes himself to exploring the science and philosophy of the human experience. To him, cognitive biases are everything and nothing.
There is nothing that is not a bias.
We prefer sweet food to bitter food, solid ground to unstable ground, and are imbued with cultural assumptions that help us live more peacefully in society. Noting that biases exist in the biological domain, Baumann frees cognitive bias from the trap of being views as an entirely mental phenomenon.
Biases do not obstruct a healthy or positive life.
Biases are shortcuts we've inherited through past generations. They are designed to help us to survive. Confirmation bias, for example, solve the problem of not being able to take in all the world's information each time we make a decision. Of course, being closed off to new information is equally hazardous in modern society, where information is the currency of our knowledge-driven world.
Baumann's favorite bias?
The uniqueness bias amuses him the most because it's a bias that each person necessarily has. We all think of ouselves as unique because each person is at the center of their own existence. But interestingly, there are circles of uniqueness. People you have close relationships with are more unique than people you don't know. Which of course has some obvious limitations as a reliable point of view.
What to do about biases
Listen better, says Baumann. Understanding the predispositions we bring to the table should make us more open to understanding other people's points of view. If you're not so special, not so right, not so perfect all the time, there's a greater likelihood that you have something valuable to learn from others.
The Buster Benson approach
Buster Benson (a marketing manager at Slack) decided to organize 175 known biases into a giant codex.
Benson (with help from illustrations by John Manoogian III), sorted biases for duplicates and grouped them into four larger categories, each called a "conundrum" or "problem". All four of these limit our intelligence but are actually trying to be helpful. According to Benson, "Every cognitive bias is there for a reason — primarily to save our brains time or energy." But the end result of utilizing such mental shortcuts, which are often useful, is that they also introduce errors into our thinking. By becoming aware of how our minds make decisions, we can be mindful of the inherent inaccuracies and fallacies and hopefully act with more fairness and grace.
Here's how Benson divides up more than 200 cognitive biases into four problems that biases actually help address:
The world is a set of information that's just too enormous for your brain to handle.
If something has already been in our memories and we're used to seeing that issue a certain way, that's how our brain is likely to react to it again. The biases that stem from this are plenty - the Attentional Bias, for example, that tells us to perceive events through our recurring thoughts at that time. This prevents us from considering alternate paths and possibilities.
Our biases that result from this kind of thinking include the context effects, the mood-congruent memory bias, or the empathy gap, which makes us underestimate the influence of visceral drives on our attitudes and actions.
We look at how much something has changed more than what the new value of this something is if it was presented by itself. Cue the Focusing effect, Money illusion, Conservatism, or Distinction bias.
And because you can't grasp everything, you'll always be missing a lot of essential information.
We utilize stereotypes and quick fill-in-the-gaps thinking to make decisions about something when we don't know everything about it. Mental mistakes like the Group attribution error, Ultimate attribution error, Stereotyping, Essentialism, the Bandwagon effect and the Placebo effect all arise from such a cognitive approach.
According to Benson, and probably to your own life experience, we also tend to like more the things and the people we know than those we don't. In this grouping, we'd find the Cheerleader effect and the Positivity effect among others.
You need to act fast, so you'll be relying on a limited set of information.
These cognitive issues arise from having to make decisions without having all the time and information you'd prefer. We often have to decide on a course of action quickly, relying on biases and instinct rather than all the possible facts.
One way to make decisions quickly is to do it with confidence, convincing yourself that what you're doing is important. Because of this, we often get overconfident, leading to such biases as the Dunning-Kruger effect, when people overestimate their abilities as well as Optimism Bias and Armchair Fallacy.
When we have to just go for it, we also tend to "favor the immediate," write Benson. The thing in front of us is worth much more than something potential and distant.
You need to remember some things. But it's impossible (and totally undesirable) to remember everything.
There's just so much information that permeates our daily lives that we are constantly made to choose between what to address and what to forget. This overload results in choosing generalizations and other biases that help us deal with the data onslaught.
Some of the tactics we rely on include creating false memories or discarding specifics in favor of stereotypes and prejudices. Unfortunately, it's just easier to function that way for some people.
We also tend to reduce events and lists to commonalities, choosing a small number of items to stand for the whole. Another thing we do is storing memories based on how we experienced them. This is when the circumstances of the experience affect the value we place on it. This is also when we get such great biases as the Tip of the tongue phenomenon, which is when we feel like we are about to remember something but we just fail to do it. You know that feeling.
Another fun modern bias of this kind is the Google effect, also called "digital amnesia". This is when we quickly forget information easily found online using a search engine like Google. Let's see if that happens with this article.
You can buy the codex (now featuring 188 biases) here. Hang it on your wall (and hopefully let some of it inform your thinking)!
"You look at this overwhelming array of cognitive biases and distortions, and realize how there are so many things that come between us and objective reality," Manoogian explained The Huffington Post. "One of the most overwhelming things to me that came out of this project is humility."
The reductive approach
While there nearly 200 cognitive biases that frame our decision making each day, here are 20 that you might want to pay particular attention to. At Business Insider, Samantha Lee put together a great infographic showing 20 cognitive biases that can get in the way of solid decision-making.
The Julia Galef approach

Julia Galef, President of the Center for Applied Rationality, says that looking at issues as an outsider is a surefire approach to outwit the commitment bias and the sunk-cost fallacy. Intel famously used this approach to leave behind a faltering memory-chip product for more lucrative ventures.
Your body’s full of stuff you no longer need. Here's a list.
Evolution doesn't clean up after itself very well.
- An evolutionary biologist got people swapping ideas about our lingering vestigia.
- Basically, this is the stuff that served some evolutionary purpose at some point, but now is kind of, well, extra.
- Here are the six traits that inaugurated the fun.
The plica semilunaris
<img class="rm-lazyloadable-image rm-shortcode" type="lazy-image" data-runner-src="https://assets.rebelmouse.io/eyJhbGciOiJIUzI1NiIsInR5cCI6IkpXVCJ9.eyJpbWFnZSI6Imh0dHBzOi8vYXNzZXRzLnJibC5tcy8xOTA5NjgwMS9vcmlnaW4ucG5nIiwiZXhwaXJlc19hdCI6MTY3NDg5NTg1NX0.kdBYMvaEzvCiJjcLEPgnjII_KVtT9RMEwJFuXB68D8Q/img.png?width=980" id="59914" width="429" height="350" data-rm-shortcode-id="b11e4be64c5e1f58bf4417d8548bedc7" data-rm-shortcode-name="rebelmouse-image" />The human eye in alarming detail. Image source: Henry Gray / Wikimedia commons
<p>At the inner corner of our eyes, closest to the nasal ridge, is that little pink thing, which is probably what most of us call it, called the caruncula. Next to it is the plica semilunairs, and it's what's left of a third eyelid that used to — ready for this? — blink horizontally. It's supposed to have offered protection for our eyes, and some birds, reptiles, and fish have such a thing.</p>Palmaris longus
<img class="rm-lazyloadable-image rm-shortcode" type="lazy-image" data-runner-src="https://assets.rebelmouse.io/eyJhbGciOiJIUzI1NiIsInR5cCI6IkpXVCJ9.eyJpbWFnZSI6Imh0dHBzOi8vYXNzZXRzLnJibC5tcy8xOTA5NjgwNy9vcmlnaW4uanBnIiwiZXhwaXJlc19hdCI6MTYzMzQ1NjUwMn0.dVor41tO_NeLkGY9Tx46SwqhSVaA8HZQmQAp532xLxA/img.jpg?width=980" id="879be" width="1920" height="2560" data-rm-shortcode-id="4089a32ea9fbb1a0281db14332583ccd" data-rm-shortcode-name="rebelmouse-image" />Palmaris longus muscle. Image source: Wikimedia commons
<p> We don't have much need these days, at least most of us, to navigate from tree branch to tree branch. Still, about 86 percent of us still have the wrist muscle that used to help us do it. To see if you have it, place the back of you hand on a flat surface and touch your thumb to your pinkie. If you have a muscle that becomes visible in your wrist, that's the palmaris longus. If you don't, consider yourself more evolved (just joking).</p>Darwin's tubercle
<img class="rm-lazyloadable-image rm-shortcode" type="lazy-image" data-runner-src="https://assets.rebelmouse.io/eyJhbGciOiJIUzI1NiIsInR5cCI6IkpXVCJ9.eyJpbWFnZSI6Imh0dHBzOi8vYXNzZXRzLnJibC5tcy8xOTA5NjgxMi9vcmlnaW4uanBnIiwiZXhwaXJlc19hdCI6MTY0ODUyNjA1MX0.8RuU-OSRf92wQpaPPJtvFreOVvicEwn39_jnbegiUOk/img.jpg?width=980" id="687a0" width="819" height="1072" data-rm-shortcode-id="ff5edf0a698e0681d11efde1d7872958" data-rm-shortcode-name="rebelmouse-image" />Darwin's tubercle. Image source: Wikimedia commons
<p> Yes, maybe the shell of you ear does feel like a dried apricot. Maybe not. But there's a ridge in that swirly structure that's a muscle which allowed us, at one point, to move our ears in the direction of interesting sounds. These days, we just turn our heads, but there it is.</p>Goosebumps
<img class="rm-lazyloadable-image rm-shortcode" type="lazy-image" data-runner-src="https://assets.rebelmouse.io/eyJhbGciOiJIUzI1NiIsInR5cCI6IkpXVCJ9.eyJpbWFnZSI6Imh0dHBzOi8vYXNzZXRzLnJibC5tcy8xOTA5NzMxNC9vcmlnaW4uanBnIiwiZXhwaXJlc19hdCI6MTYyNzEyNTc2Nn0.aVMa5fsKgiabW5vkr7BOvm2pmNKbLJF_50bwvd4aRo4/img.jpg?width=980" id="d8420" width="1440" height="960" data-rm-shortcode-id="8827e55511c8c3aed8c36d21b6541dbd" data-rm-shortcode-name="rebelmouse-image" />Goosebumps. Photo credit: Tyler Olson via Shutterstock
<p>It's not entirely clear what purpose made goosebumps worth retaining evolutionarily, but there are two circumstances in which they appear: fear and cold. For fear, they may have been a way of making body hair stand up so we'd appear larger to predators, much the way a cat's tail puffs up — numerous creatures exaggerate their size when threatened. In the cold, they may have trapped additional heat for warmth.</p>Tailbone
<img class="rm-lazyloadable-image rm-shortcode" type="lazy-image" data-runner-src="https://assets.rebelmouse.io/eyJhbGciOiJIUzI1NiIsInR5cCI6IkpXVCJ9.eyJpbWFnZSI6Imh0dHBzOi8vYXNzZXRzLnJibC5tcy8xOTA5NzMxNi9vcmlnaW4uanBnIiwiZXhwaXJlc19hdCI6MTY3MzQwMjc3N30.nBGAfc_O9sgyK_lOUo_MHzP1vK-9kJpohLlj9ax1P8s/img.jpg?width=980" id="9a2f6" width="1440" height="1440" data-rm-shortcode-id="4fe28368d2ed6a91a4c928d4254cc02a" data-rm-shortcode-name="rebelmouse-image" />Coccyx.
Image source: Decade3d-anatomy online via Shutterstock
<p>Way back, we had tails that probably helped us balance upright, and was useful moving through trees. We still have the stump of one when we're embryos, from 4–6 weeks, and then the body mostly dissolves it during Weeks 6–8. What's left is the coccyx.</p>The palmar grasp reflex
<img class="rm-lazyloadable-image rm-shortcode" type="lazy-image" data-runner-src="https://assets.rebelmouse.io/eyJhbGciOiJIUzI1NiIsInR5cCI6IkpXVCJ9.eyJpbWFnZSI6Imh0dHBzOi8vYXNzZXRzLnJibC5tcy8xOTA5NzMyMC9vcmlnaW4uanBnIiwiZXhwaXJlc19hdCI6MTYzNjY0MDY5NX0.OSwReKLmNZkbAS12-AvRaxgCM7zyukjQUaG4vmhxTtM/img.jpg?width=980" id="8804c" width="1440" height="960" data-rm-shortcode-id="67542ee1c5a85807b0a7e63399e44575" data-rm-shortcode-name="rebelmouse-image" />Palmar reflex activated! Photo credit: Raul Luna on Flickr
<p> You've probably seen how non-human primate babies grab onto their parents' hands to be carried around. We used to do this, too. So still, if you touch your finger to a baby's palm, or if you touch the sole of their foot, the palmar grasp reflex will cause the hand or foot to try and close around your finger.</p>Other people's suggestions
<p>Amir's followers dove right in, offering both cool and questionable additions to her list. </p>Fangs?
<blockquote class="twitter-tweet" data-conversation="none" data-lang="en"><p lang="en" dir="ltr">Lower mouth plate behind your teeth. Some have protruding bone under the skin which is a throw back to large fangs. Almost like an upsidedown Sabre Tooth.</p>— neil crud (@neilcrud66) <a href="https://twitter.com/neilcrud66/status/1085606005000601600?ref_src=twsrc%5Etfw">January 16, 2019</a></blockquote> <script async src="https://platform.twitter.com/widgets.js" charset="utf-8"></script>Hiccups
<blockquote class="twitter-tweet" data-conversation="none" data-lang="en"><p lang="en" dir="ltr">Sure: <a href="https://t.co/DjMZB1XidG">https://t.co/DjMZB1XidG</a></p>— Stephen Roughley (@SteBobRoughley) <a href="https://twitter.com/SteBobRoughley/status/1085529239556968448?ref_src=twsrc%5Etfw">January 16, 2019</a></blockquote> <script async src="https://platform.twitter.com/widgets.js" charset="utf-8"></script>Hypnic jerk as you fall asleep
<blockquote class="twitter-tweet" data-conversation="none" data-lang="en"><p lang="en" dir="ltr">What about when you “jump” just as you’re drifting off to sleep, I heard that was a reflex to prevent falling from heights.</p>— Bann face (@thebanns) <a href="https://twitter.com/thebanns/status/1085554171879788545?ref_src=twsrc%5Etfw">January 16, 2019</a></blockquote> <script async src="https://platform.twitter.com/widgets.js" charset="utf-8"></script> <p> This thing, often called the "alpha jerk" as you drop into alpha sleep, is properly called the hypnic jerk,. It may actually be a carryover from our arboreal days. The <a href="https://www.livescience.com/39225-why-people-twitch-falling-asleep.html" target="_blank" data-vivaldi-spatnav-clickable="1">hypothesis</a> is that you suddenly jerk awake to avoid falling out of your tree.</p>Nails screeching on a blackboard response?
<blockquote class="twitter-tweet" data-conversation="none" data-lang="en"><p lang="en" dir="ltr">Everyone hate the sound of fingernails on a blackboard. It's _speculated_ that this is a vestigial wiring in our head, because the sound is similar to the shrill warning call of a chimp. <a href="https://t.co/ReyZBy6XNN">https://t.co/ReyZBy6XNN</a></p>— Pet Rock (@eclogiter) <a href="https://twitter.com/eclogiter/status/1085587006258888706?ref_src=twsrc%5Etfw">January 16, 2019</a></blockquote> <script async src="https://platform.twitter.com/widgets.js" charset="utf-8"></script>Ear hair
<blockquote class="twitter-tweet" data-conversation="none" data-lang="en"><p lang="en" dir="ltr">Ok what is Hair in the ears for? I think cuz as we get older it filters out the BS.</p>— Sarah21 (@mimix3) <a href="https://twitter.com/mimix3/status/1085684393593561088?ref_src=twsrc%5Etfw">January 16, 2019</a></blockquote> <script async src="https://platform.twitter.com/widgets.js" charset="utf-8"></script>Nervous laughter
<blockquote class="twitter-tweet" data-lang="en"><p lang="en" dir="ltr">You may be onto something. Tooth-bearing with the jaw clenched is generally recognized as a signal of submission or non-threatening in primates. Involuntary smiling or laughing in tense situations might have signaled that you weren’t a threat.</p>— Jager Tusk (@JagerTusk) <a href="https://twitter.com/JagerTusk/status/1085316201104912384?ref_src=twsrc%5Etfw">January 15, 2019</a></blockquote> <script async src="https://platform.twitter.com/widgets.js" charset="utf-8"></script>Um, yipes.
<blockquote class="twitter-tweet" data-conversation="none" data-lang="en"><p lang="en" dir="ltr">Sometimes it feels like my big toe should be on the side of my foot, was that ever a thing?</p>— B033? K@($ (@whimbrel17) <a href="https://twitter.com/whimbrel17/status/1085559016011563009?ref_src=twsrc%5Etfw">January 16, 2019</a></blockquote> <script async src="https://platform.twitter.com/widgets.js" charset="utf-8"></script>Lessons from the Roman Empire about the danger of luxury
Are we enslaved by the finer things in life?
- The Roman writer, Tacitus, argued that the Roman Empire was built by enslaving conquered people who became accustomed to fine living and luxury.
- Technology today has become so essential to our daily lives that it seems impossible to break free of it. It's as much a cage as a luxury.
- Being dependent on a thing gives it power over you. To need something or someone is, for better or worse, to limit yourself.
Supernova 2014J
Despite social pressure, boys and girls still prefer gender-typical toys
Fifty years of research on children's toy preferences shows that kids generally prefer toys oriented toward their own gender.
