Chris Castig Co-founder of Adjunct Prof at Columbia University Business School.

Blink by Malcolm Gladwell | Book Summary and Notes

6 min read

Why should you read Blink?

In Blink, Gladwell shares stories that celebrate the power of quick decisions, as well as those moments when our instincts betray us.

Gladwell wants you to finish the book having learned three things:

  1. Decisions made very quickly can be every bit as good as decisions made cautiously and deliberately. [14]
  2. How to know when you can trust your instincts, and when should you should be wary of them.
  3. Snap judgments and first impressions can be learned and controlled – if you’re willing to practice your “Thin-slicing” skills.

Reading Blink helped me become a more critical thinker and made me understand that decision-making is complex business. When should you trust your gut? And when should you be skeptical of it? That’s Blink.

What is Thin-slicing?

“Thin-slicing” is the unconscious mind’s ability to find patterns in situations and behavior based on very narrow slices of experience. [23]

What is some examples of Thin-slicing in real life?

Here are a my Top 3 favorite examples of Thin-slicing from Gladwell’s book:

1.  How John Gottman can spot divorce years before a married couple knows it

Psychologist John Gottman (University of Washington) can predict with 95% accuracy whether a couple will still be married fifteen years later. [21]  And he can do this in less than 15 minutes.

He’s gone on to write a few books including The Mathematics of Marriage and The Seven Principles for Making Marriage Work.

So, how does he do it?

Gladwell argues that Gottman knows what to look for:

“He’s looking for patterns and cues. He has found that he can find out much of what he needs to know just by focusing on what he calls the Four Horsemen: defensiveness, stonewalling, criticism, and contempt. Contempt is closely related to disgust, and what disgust and contempt are about is completely rejecting and excluding someone from the community.” [33]

2. How your body knows a winning card before you do  [8]


Imagine you were asked to play a very simple game: in front of you are four decks – two of them red and the other two blue. Each card in these decks will either WIN or LOSE you some money.

You start picking cards randomly from the four decks. By the time you pull your 50th card from the decks you realize, “Hey the red deck is way worse than the blue deck.” Now, the interesting thing is that while you consciously realize it at the 50th card, your body (and intuition) knew it at card 10th card.

On your body’s intuition Gladwell writes,

“What the Iowa scientists found is that gamblers started generating stress responses to the red decks by the tenth card, forty cards before they were able to say that they had a hunch about what was wrong with those two decks. More important, right around the time their palms started sweating, their behavior began to change as well. They started favoring the blue cards and taking fewer and fewer cards from the red decks. In other words, the gamblers figured the game out before they realized they figured the game out” [9]

3. How you can learn about someone very quickly without actually meeting them

How would you get to know me better: a) interviewing my friends, or b) coming into my bedroom when I’m not there and spending 30 minutes looking around?

According to Gladwell (and the work of Samuel Gosling) coming by my bedroom might be a better way to get to know me than ACTUALLY getting to know me.

Gladwell writes,

“If you want to get a good idea of whether I’d make a good employee, drop by my house one day and take a look around.” [36]

Question: What can you learn about me from these two photos of my bedroom?  Write your answers down in the comments and I’ll let you know if you’re correct.

castig apartment2 castig apartment

Blink Chapter 5: The Right – and Wrong – Way to Ask People What They Want

Chapter 5 of Blink is packed full of some of my favorite stories from Blink including:  “The Chair of Death,” the fall of the Christian Brothers whiskey, the worst car every made, why All in the Family and The Mary Tyler Moore Show probably should never have made it to television, and the story of the New Jersey super-tasters.

Of all of these stories, I’m going to focus on my three favorite: Kenna, Pepsi vs. Coke, and Butter vs. Margarine. 

1. The Kenna from Blink

“How to classify Kenna is a difficult question, but, at least in the beginning, it wasn’t one that he thought about a great deal.”

Around 2003, Kenna was very up and coming. Everyone loved Kenna, including:

  • U2’s manager, Paul McGuiness
  • Fred
  • MTV and MTV2
  • No Doubt
  • Fans (he was selling out shows)


Someone very important HATED his sound: record company focus groups.

Why didn’t they like him?

Gladwell’s answer is that the curse of the expert, and sensation transference are responsible. On the podcast I go into a lot more depth about these concepts – and because of that I’m not going to go so deep here. (aka. Listen to the podcast).

Watch the video yourself. How would you rate Kenna’s music on a scale from 0 to 4. And then listen to the podcast to see how the music industry rated him and why you may agree with Fred Durst more than you’d like to admit to yourself. (If you’re never heard Kenna before – put your rating down in the comments below). 

Kenna on trusting focus groups vs. listener faith, 

“I guess they’ve gone to their focus groups, and the focus groups have said, ‘No, it’s not a hit,’ They don’t want to put money into something that doesn’t test well,” Kenna says. But that’s not the way this music works. This music takes faith. And faith isn’t something the music business is about anymore.” [188]

2. Coke vs. Pepsi

In the late 70’s, Coke had a problem: Pepsi. Gladwell writes, 

“In 1972, 18% of soft drink users said they drank Coke exclusively, compared with 4% who called themselves exclusive Pepsi drinkers. By the early 1980s Coke dropped to 12% and Pepsi had risen to 11%.” [156]

The rise in sales for Pepsi (and decline for Coke) was linked to the Pepsi Challenge ad campaign. Take a look:

In blind taste tests, it appeared that America was choosing Pepsi. Did that mean Pepsi tasted better than Coke?

America started to believe Pepsi was the best cola. And so did Coke! And that’s when Coke began to update their recipe.

Gladwell on New Coke, 

“This was the genesis of what came to be known as New Coke. Coke’s scientists went back and tinkered with the fabled secret formula to make it a little lighter and sweeter – more like Pepsi. immediately Coke’s market researchers noticed an improvement. In blind taste tests of some of the early prototypes, Coke pulled even with Pepsi. They tinkered some more. In September of 1984, they went back out and tested what would end up as the final version of New Coke. […] New Coke beat Pepsi by 6 to 8 percentage points. Coca-Cola executives were elated.”

The only problem was, in the real world, New Coke wasn’t better than Pepsi. Gladwell writes, 

“It was a disaster. Coke drinkers rose up in outrage against New Coke. There were protests around the country. […] The story of New Coke is a really good illustration of how complicated it is to find out what people really think.” [158]

The conclusion Gladwell makes is that the Pepsi Challenge is flawed, because no one drinks either Coke or Pepsi blind. If you’re going to test what people like, you need to keep as many variables as possible the same. He writes, 

“A sip is very different from sitting and drinking a whole beverage on your own. Sometimes a sip tastes good and a whole bottle doesn’t. That’s why home-use test give you the best information. […] The entire principle of a blind taste test was ridiculous. They shouldn’t have cared so much that they were losing blind taste tests with old Coke, and we shouldn’t at all be surprised that Pepsi’s dominance in blind taste tests never translated to much in the real world. Why not? Because in the real world, no one ever drinks Coca-Cola blind.”

3. Butter vs. Margarine

 Butter vs. Margarine

Sensation transference: when people give an assessment of something they might buy in a supermarket or a department store, without realizing it, they transfer sensations or impressions that they have about the packaging of the product to the product itself. [160]

The term sensation transference was coined by a guy named Louis Cheskin, who worked on margarine.

These days, most people think butter and margarine are relatively the  same thing. But in the 1940s that was not the case: margarine was extremely unpopular. People thought it was gross.

Why didn’t people like margarine? Cheskin decided to find out. His first assumption was the look of margarine: it was white, and didn’t have the nice packaging that butter had. So in order to improve people’s perception of margarine, a) Cheskin colored his margarine yellow so that it would look like butter. b) He gave it a more impressive name: Imperial Margarine, and an “impressive looking crown on the package.”

That’s sensation transference at work! And that’s why you likely don’t think of margarine as being gross.

Gladwell also points out two other examples of sensation transference that marketers take advantage of: 

If you add 15% more yellow to the green on the package of a 7-Up people report more lime or lemon flavor. [163]

When Del Monte took the peaches out of the tin and put them in a glass container, people said, “Ahh, this is something like my grandmother used to make”. People say peaches taste better when they come in a glass jar. [164]

Listen to Blink on the On Books Podcast


Title: Blink: The Power of Thinking Without Thinking
Author: Malcolm Gladwell
Hardcover: 296 pages
Publisher: Back Bay Books; 1 edition (April 3, 2007)

Buy Blink on Amazon
Listen to Blink on Audible (free trial)

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Chris Castig Co-founder of Adjunct Prof at Columbia University Business School.