Riddle me this:

“If it takes 5 machines 5 minutes to make 5 widgets, how long would it take 100 machines to make 100 widgets”—100 minutes or 5 minutes (65)?

If you answered “100 minutes,” you’re not alone … and you’re dead wrong. Think about it. In Thinking, Fast and Slow, Kahneman explains why.

We have two types of thinking systems (thus, the title of the book). System one is intuitive and answers quickly. System two requires more thought and answers slowly. Both systems are valuable and necessary. Kahneman’s spent his lifetime studying these systems and has developed and published many experiments over the years (including the one above) which exploit the flaws in our systems.

In Thinking, Fast and Slow, Kahneman helps us to recognize when our minds let us down (i.e. narrative fallacies, planning fallacies, WYSIATI, etc.) and gives us the tools to recognize our own errors.

This book is detailed, thorough, and absolutely fascinating. Kahneman walks the reader through many of the test scenarios he developed over the years. Even if you prepare yourself for the “trick” and try to answer correctly, human nature wins out. It’s certainly a good dose of humility!

Many of these experiments were carried out with his friend and colleague, Amos Tversky, to whom the book is dedicated. The friendship between them and their mutual fascination with how the mind works makes this book on sociology border on memoir at times.

Read and be fascinated at your incredibly powerful and deeply flawed mind!

—Daniel Kahneman, Thinking, Fast and Slow (Toronto, ON: Doubleday Canada, 2011).