Consider what happens when you attempt to use your intuition to answer the following question:
“A bat and ball cost $1.10. The bat costs $1 more than the ball. How much does the ball cost?”
Most likely, the first answer that popped into your head was “The ball costs 10 cents.” It seems reasonable, and is totally wrong. If it were true, then the bat would cost $1.10, making the total cost $1.20, not $1.10.
The correct answer is 5 cents: $0.05 + $1.05 = $1.10. But this simple problem, which Daniel Kahneman describes in detail in Thinking, Fast and Slow, highlights tremendous findings about the ways in which we think.
In short, it is as if we operate on two levels: there is an intuitive level (Kahneman refers to as System 1), which is able to spit out answers we all know fairly simply. System 1 is what allows you to quickly respond with 20 when someone asks what 4 times 5 is – and System 1 runs on very little mental energy.
System 2, on the other hand, is the mental function which operates when you are asked something more mentally demanding: what is 27 times 145? Surely, you could figure it out, but it’d take you a minute to perform the calculations on paper or in your head. This system handles the more difficult tasks your brain faces, and expends much more energy and focus.
So let’s get back to the initial question about the baseball bat and ball. Notice that the first response which comes to mind, which is intuitive, is wrong! System 1 tries to answer the question, but it comes up short. It is possible to miss correct answers or lose a train of logic by relying too heavily on the intuitive nature of this type of thinking, but we do it all the time! Our more thoughtful process, System 2, would be able to easily answer the question, and can even act as a filter to let us know “5 cents seems right, but it may be too easy!” The question is: are we willing to put it to use?
Intuition is extremely useful for handling certain regular tasks and answering many simple questions, but very often, our intuition is wrong. Yet, many individuals rely on this intuition to make very important decisions, answer complex questions, and engage in heated debates with nothing more than a quick and reasonable guess. In the realm of logic and reason, System 2 rules. So above all else, be wary as to when you may fall into the trap of your intuitive System 1, and learn to kick your lazy System 2 into gear!