The Dangers of Fast Thinking

I've been reading a book lately chock full of interesting insights.  It's called Thinking, Fast and Slow, written by Daniel Kahneman, a dude who won the Nobel Prize in Economics in 2002.  So I guess he knows his shit.

As you can guess from the title, the book analyzes human decision making.  In particular, it focuses on errors in our decision making that we make repeatedly, without seeming to notice it, and a major reason--among many others--that we make these errors is that we tend to rush our way to answers to complicated questions.

Now, several months ago, I read Blink, a book by Malcolm Gladwell, on the same topic.  In Blink, however, the main point of the book seemed to be that we should trust our quick responses.  The first example given in that book is a statue that a museum on the East Coast wanted to buy, but they wanted to ensure that the statue was authentic first.  So they hired a couple of experts to come look at it.  In a glance, the experts knew that it was fake.  However, they were unable to explain why it was fake.  In this story, their initial knee-jerk reaction turned out to be accurate.

Thinking, Fast and Slow comes at these quick decisions from a more skeptical point out view.  The human mind falls victim to the WYSIATI pitfall--which stands for What You See Is All There Is.  In other words, when we are considering a question, we tend to use only the data available to us, without bothering to look for more evidence.  For example, consider the following question from the book:

Consider the letter K.  Is K more likely to appear as the first letter in a word OR as the third letter?

When I tried to answer this question, I had some trouble.  I felt like there were so many words that I couldn't think of, but I still made a guess.  My guess was that K was likely to be the first letter.  Did you make the same guess?

If so, Kahneman's guess is that we would guess that K is more likely to appear as the first letter.  Why?  It is much easier for our minds to think of words that start with K than it is to search for words that have K as the third letter.  We pile up those words in our mind, we can't locate many third-letter K words, and so we guess that there are more words that start with K.  WYSIATI.  Our guess, as it turns out, would be wrong.

We following the WYSIATI pitfall when it comes to all kinds of things.  Take gun control.  Many people have strong feelings on the issue one way or the other.  But how much do we actually truly know about the subject?  Does gun control actually reduce crime?  How can we possibly answer this question with so many moving variables in the world?  Despite the lack of knowledge on the issue, many people have strong thoughts on the subject, even though their opinions are based on extremely limited evidence.

Another argument that Kahneman makes is that our minds are just downright lazy.  To demonstrate this point, he poses the following question.  Give it a try.

A bat and ball cost $1.10.

The bat costs one dollar more than the ball. 

How much does the ball cost?

Got an answer?  Kahneman guesses that a number came rather quickly to your mind.  That number is ten cents.  (Is that true?  It was for me.)  He claims that 10 cents came to your mind quickly because it was intuitive and appealing.  It was also wrong.  If the ball costs 10 cents, then the bat costs $1.10--one dollar more--and so both of them cost $1.20.  Instead, the correct answer is 5 cents.

As I said, I chose ten cents almost immediately, but I was aware that I was reading a book that might contain such questions, and so I found the correct answer after giving it some more thought.  But if I hadn't been on my toes, I likely would've stuck with my initial incorrect answer.  And I imagine that my mind makes similar errors all the time, and I never notice it.

There's a whole lot more to the book.  In fact, I've only given two of his ideas, and two examples, from the first 20 pages or so.  It is quite a compelling read, one which I recommend highly.