Book notes
You Are Not So Smart

You Are Not So Smart by David McRaney

Read in January 2021

"In science, we move closer to the truth by seeking evidence to the contrary. Perhaps the same method should inform our opinions as well."


External factors, certain behavior, and prior experience effects our unconscious thinking while making decisions.

Unconscious is always working to make a meaning out of the sensor data and process.

When a stimulus effects the way we behave and think, or the way we perceive another stimulus later on, it's called priming.

Study: did you just wash your guilt away?

People asked to think about their biggest immoral behavior. Half of them washed their hands after the experiment, and the other half didn't.

41% of the people who washed their hands said yes to taking part in a later research to help a desperate student. 74% of who didn't wash their hands attended to that.

We relate "washing/cleaning" to cleansing, so the first half "washed their guilt away".

Study: I negotiate like a businessman because that's how I roll

People sat in two different rooms: one filled with business material such as suitcases, and another with neutral stuff.

Then they played an "ultimatum game" with somebody to split a 10$ reward.

Business room tend to negotiate more (33% wanted to split evenly) then the neutral room (91%).

Funny thing is they didn't realize the objects in the room, and constructed narratives to make a reasoning of their behavior.

How to deal with priming?

We can't self-prime, it has to be unconscious. In fact, it's enormously helps us by freeing up space for the conscious mind in the case of executive decisions.

Yet, we can create environments to nudge our mind to create mental states we wish to arrive.

Some of the primes are unintended, but in many cases there's an agent on the other end who plotted against our judgment. Business discovered it before the psychologists: casinos (sound of geld, no day/night distinction), coca-cola (ownership of santa claus).


We are often ignorant of our motivations, and create fictional narratives to explain our decisions, emotions, and history. We don't realize it's not the absolute truth, and find it hard to falsify.

"Blindspot": the point where our optic nerve breaks into retina, and the moving dots experiment. We can't perceive the second dot, yet the same doesn't apply when we close our eyes and look around the room. The mental photoshopping happens in that case. The way we fill the gaps of memories is similar, based on the history and beliefs.

Over time, those narratives build up the story of who we are.


Confabulation observed more thoroughly in split-brain patients. (Two halves of the brain are disconnected, sometimes it's done surgically to make diseases like epilepsy more manageable.) They have a clear distinction of their visual hemispheres. Our left-brain is more capable when it comes to reasoning, where the right-brain does more autonomous tasks.

Although the patients can live an OK life, the lack of connection on their two sides creates a consistent confabulation. But they never feel confused of deceptive.

Example study: Split-brain patients are shown two words: "bell" on the left, and "music" on the right. Then they are asked to point out with their right hand in a series of photos: bell, drummer, organ, and trumpet.

They only chosen "bell" and explained it by "hearing the college's bell towers" before the experiment.

When the left hemisphere is forced to explain why the right hemisphere is doing something, it creates a fiction that both sides agree on.


Phenomenology is the result of thinking, not the process that appears in the consciousness. We collect and report what the unconscious produces.

Explaining notions like colors and taste is hard without actually experiencing it. These are called "qualia", the minimum building blocks of the consciousness.

How to deal with confabulation?

Take your narratives with a grain of salt. Just like you are listening a story of the last night from a friend.

Confirmation Bias

Our opinions are the result of years of paying attention to information that confirmed what we believed, while ignoring information that challenged our preconceived notions.

Confirmation bias is seeing the world through a filter. The real trouble beings when it distorts our active pursuit of facts.

How to deal with it?

In science, we move closer to the truth by seeking evidence to the contrary. Perhaps the same method should inform our opinions as well.

Hindsight Bias

We tend to edit our memories so we don't seem like a dimwit (stupid) when things happen in a way we couldn't have predicted: "I KNEW IT!"

Once we learn from our mistakes, we just replace the bad information with the good one, and delete the garbage. That's a great way to declutter.

How to deal with it?

Have an healthy skepticism when politicians and businessman talk about their past decisions.

Oh, also yourself.

The Texas Sharpshooter Fallacy

If hindsight bias and confirmation bias had a baby, that would be this one.

We correlate random events with each other to determine a cause and effect: Kennedy/Lincoln assassinations, Titan(book)/Titanic(movie), Nostradamus guessing Hitler's arrival.

It resembles a cowboy shooting at the barn and drilling random holes. Then he paints a bulls-eye around the spots with many holes. Well, he's a sharp-shooter now.

How to deal with it?

Recognize all the randomness what got us here. The whole universe is an ocean of coincidences...