Thinking, Fast and Slow

Book Review: Thinking, Fast and Slow by Daniel Kahneman

Thinking Fast and SlowScientists love to divide human thinking into two parts: right brain vs. left brain, rational vs. emotional, conscious vs. subconscious, and no doubt many others. Daniel Kahneman, Nobel Prize winner in Economics, proposes a simple split to explain much of human behavior: fast vs. slow. He makes it clear that this is an artificial construct, but at the same time draws upon decades of research to demonstrate its utility.

System 1 vs. System 2

Fast thinking (dubbed System 1 by Kahneman) is unconscious, emotional, instinctive. Fast thinking results in snap judgments and, sometimes, prejudice. Slow thinking (System 2) is what most of us would consider actual thought: it’s conscious, deliberative, and mostly rational. We use both fast and slow thinking when we process information and make decisions, according to Kahneman, but we tend to avoid slow thinking when we can. Slow thinking is more work for our brain and consumes more resources. Fast thinking enables us to get through the day by handling routine decisions with minimum fuss. When we make important decisions, both systems can be engaged even though we are mainly aware of the slow thinking part.

A Deep Dive

Recent years have seen a plethora of books dissecting our sometimes irrational thinking processes – Predictably Irrational, Brain Bugs, Mistakes Were Made (but not by me), Sway, Nudge, How We Decide, The Invisible Gorilla, and others all added to the conclusion that human decision making is far less rational than we think. Indeed, my own book, Brainfluence, is mostly based on that fact. (Brainfluence focuses on practical applications, not the underlying science.)

Thinking, Fast and Slow, however, digs deeper than any of these and explores a broader range of behaviors. It’s a big book – 512 pages – and Kahneman patiently and clearly walks us though topics ranging from “rare events” to “causes trump statistics.”

The breadth and depth of Thinking, Fast and Slow, as well as the fact that much of the research described was carried out by Kahneman and his associates, add to the persuasiveness of his case. To be sure, Kahneman cites many other researchers and mentions numerous studies that will be familiar to students of this space (and a few that may not be), but he is clearly master of this material.

Insights Abound

Kahneman’s book isn’t about marketing, investing, politics, or similar topics, but it yields plenty of insights into human behavior that can guide those, and other, endeavors. A typical gem, all too often exploited in politics:

A reliable way to make people believe in falsehoods if frequent repetition, because familiarity is not easily distinguished from the truth.

Kahneman notes that even repetition of a fragment of a false statement lends credibility to it because of the concept of cognitive ease; if it’s easier for our brain to process, it’s more believable.

Kahneman knows how to turn a phrase, too. Discussing the famous “gorilla study,” he writes,

The gorilla study illustrates two important facts about our minds; we can be blind to the obvious, and we are also blind to our blindness.

The latter point is an ongoing theme of the book: not only do our powers of observation and reasoning fail us, but we rarely become aware of those failures.

Lay readers need not be put off by the size of the book and credentials of the author. I’ve never seen Kahneman lecture, but I’d guess he’s a very popular professor. His style is exceptionally clear and actually entertaining; he seasons his writing with gentle humor. Thinking, Fast and Slow is brilliant and a must-read for anyone interested in the brain, mind, thought, and decision-making. Indeed, I’m finding it is a go-to reference for many cognition topics.

Amazon Link: Thinking, Fast and Slow
Kindle Link: Thinking, Fast and Slow


This post was written by:

— who has written 985 posts on Neuromarketing.

Roger Dooley writes and speaks about marketing, and in particular the use of neuroscience and behavioral research to make advertising, marketing, and products better. He is the primary author at Neuromarketing, and founder of Dooley Direct LLC, a marketing consultancy. Follow him on Twitter.

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11 responses to "Thinking, Fast and Slow" — Your Turn


Andreas 22. March 2012 at 10:51 am

Sounds like an interesting topic but also a bit dry. Do you recommend it for people that are interested in a general knowledge way, or is it just for real brain “nerds”?


Roger Dooley
Twitter: rogerdooley
22. March 2012 at 11:07 am

Well, it’s a real feast for brain nerds, Andreas, but I think the book has plenty to offer the reader who has a general interest in psychology and thinking. It definitely doesn’t read like a textbook. It’s a non-fiction best-seller, so clearly it has broad appeal. The length may be a little daunting, but there’s no reason why a casual reader couldn’t consume it in chunks or even skip to parts that look particularly interesting.



Gabriela 28. March 2012 at 8:34 am

Is one of your book saying about the influence of marketing in the brain , specific for the actual technologic products ? Thank you.


Chester Butler
Twitter: TheButlerCo
22. March 2012 at 11:03 am

Thanks for the review. I put it on my reading list. I hope it has the thorough references like Brainflouence! I find them very helpful.


Roger Dooley
Twitter: rogerdooley
22. March 2012 at 11:25 am

Chester, I did read an Amazon review that said the references are easier to use in the paper version than the Kindle version (which I have). I can’t verify that. While they references are listed at the end of the book, they aren’t tied by numbers to specific text elements (Kindle version).



Chip @ Home Remodeling 22. March 2012 at 2:55 pm

You have to be both, slow and aware when making the big decisions but being impulsive and quick witted is what makes life interesting when its not a do or die situation. Sounds like a great read. Nice review as well, by the way.


Zach 22. March 2012 at 3:22 pm

I just started reading this a week or so ago and I’m having a hard time putting it down. It provides a lot of great insights into human decision making.
Roger, I also wanted to thank you for the excellent presentation at Conversion Conference. I was hoping to catch up with you at the conference but I was pretty busy running back and forth between the sessions at Predicitive Analytics World and eMetrics in addition to the Conversion Conference.


Roger Dooley
Twitter: rogerdooley
24. March 2012 at 10:01 am

Glad you enjoyed the preso, Zach, and sorry we didn’t connect there. I’ll be at the Affiliate Summit in Austin and Pubcon LV, among others. Hope to see you at a future event!



Elena Anne
Twitter: Elena__Anne
23. March 2012 at 11:24 am

So since your reactions are basically the “fast” side of your brain, we need to train that side. If you can form your reactionary mind you will excel in any action that requires speed and will make you more efficient. Instead of having to consciously think about your actions you just become and do. Sounds like a great book I will have to pick it up.


Jurek Leon 24. March 2012 at 1:35 am

Like Zach I’m reading ‘Thinking Fast and Slow’ at the moment. I’m also finding Kahneman’s writing style to be easy to absorb and certainly not dry or academic. I’m only on page 50 so your review is a real help, thanks Roger.


PartySuppliesIL 28. March 2012 at 6:16 pm

Sounds like an interesting read, but also something I’d have to spend some time on to get into the nitty-gritty to fully understand everything. The brain is just so interesting!


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