The fundamental theory that is necessary to understand rational (and irrational) thinking is the concept of dual modes of thinking that we all employ on a daily basis: System 1 and System 2.. System 1 is fast, intuitive, creative, emotional and error-prone.  When we are tired and depleted, we usually rely on System 1, because it is nearly effortless decision making.  If you’re blearily watching infomercials at 2:00 am and you really want to buy the Shake Weight, then your System 1 is probably dominating your thinking, as your effortful System 2 fell asleep before Letterman.

Conversely, System 2 is slow, analytical, and lazy, because it requires a relatively large amount of energy.  This is where most of our analytical thinking takes place, and System 2 will kick in if it detects that System 1 is about to make an error in judgment.  For a demonstration of this, quickly answer this question:

A bat and a ball cost $1.10 in total. The bat costs $1 more than the ball. How much does the ball cost?

Did you say (or want to say) 10 cents?  Good answer, except that it’s incorrect.  Your System 1 overpowered your thought processes, and your System 2 didn’t catch the error.   The actual answer is 5 cents.  If you got that answer right off the bat, then you’re in the roughly 20% of people that don’t often make those errors.  It is obvious once you think about it for a minute, but if you didn’t use your System 2, you were probably caught in the trap (don’t worry if you were....I was caught the first time I too!).

Now try this question:

If it takes five machines five minutes to make five widgets, how long does it take 100 machines to make 100 widgets?

The expected System 1 answer is 100 minutes, but the correct answer is 5 minutes (think about it?).  Though chances are higher you got this answer correct just because the strike-through make it a bit harder to read (or perhaps because you were cued by the earlier question...).  Studies show that inducing cognitive strain, such as making the question smaller and harder to read, increased performance on these questions.   For example, in a Princeton study, 90% of students missed at least one question in a series of these questions dubbed the Cognitive Reflection Test – developed by Shane Frederick at MIT – but when they made the font smaller and harder to read, only 35% missed at least one question.  This shows CAN trick our mind into using System 2, but sometimes it just takes a little cajoling!

Now, you must wonder how this applies to your life?  These two systems are unconsciously used in tandem, sometimes to negative effects.  For example, one study of parole judges found that the success rate of parole applicants depended solely on when the judges had last eaten.  The success rate was highest just after a break, and slowly descended to near 0% until the next break.  In this instance, as judges grew weary, their System 1 processes took over, and they clearly did not consider all parole applicants equally.  Consider this effect the next time you’re considering a pile of proposals or grading a stack of papers, as  your judgments will probably be subconsciously influenced by the amount of time since your last coffee break.

We like to think that we are all rational creatures, and in the right environments with the right stimuli, we are.  However, it has become increasingly apparent that our minds are incredibly susceptible to influences and biases of which most of society is unaware.  Breaking this guise of rationality is what earned Daniel Kahneman his Nobel Prize.

So, the next time you see an advertisement that is in large, easy to read letters, remember that it is aimed at taking advantage of your impulsive and emotional System 1, and that you should moderate your response with a brief moment of System 2 thought (and all it takes is a minute!).  With enough practice and experience, you can inform your System 1’s intuition so that you don’t end up buying that tchotchke at the grocery store checkout line just because it’s on sale.  I challenge you to look around in your own world and examine how you use System 1 and System 2 to make decisions in your own life.

Until next time...thank you for reading!


Sources and Further Reading:

Daniel Kahneman, Thinking Fast and Slow