Imagine you had just received a bonus. You are debating whether to spend the sum on a vacation in Rio de Janeiro. This is a tough decision. You have never been to Rio. How do you decide if a week in Rio is the best way to spend your bonus?
Perhaps the most precise way to determine preference is to sample the options. To solve the “vacation dilemma” you may want to spend a day in Rio before buying a ticket. In some instances it is indeed possible to try out the alternatives before making a decision; most ice-cream parlours, for example, will let you taste different flavours prior to making a purchase. However, in many instances, sampling is not an option. Landlords will not allow sleepovers before you sign the lease, romantic partners will not wait around while you try out other possibilities, and no magic carpet will waft you to Rio for a sneak preview.
How then, in the absence of prior experience, do we determine which alternative we are likely to prefer in the future? One tool our brain uses to solve this problem is imagination. By using imagination we can simulate a range of future scenarios in our mind to predict the pleasure or pain they are likely to entail.
This is a useful tool in principle. However, there is an obstacle - our images of the future are inherently biased. This is in part because they are susceptible to our strong motivation to believe that the future will be bright (this is known as the optimism bias), and in part because to predict the future we rely on memories of our past. To estimate how much we will enjoy a week in Rio, for example, we will retrieve memories of previous holidays to sunny destinations. In theory this can be an effective strategy. The problem, though, is that we tend to recall the past as a concentrated timeline of emotionally exciting events. The boring bits just fade away. This leads us to predict that the future will be more colourful and more intense than it ends up being.
Our tendency to mispredict the future can lead to bad decisions. We may, for example, decide to spend a large amount of money on an upcoming vacation, believing that the time spent away will be extremely pleasurable. But studies show that people expect to enjoy a vacation more than they end up doing. If we are made aware of our biases, however, we can use that information to adjust our predictions accordingly and make better choices.
Tali Sharot is author of “The Optimism Bias” (published in the UK by Constable & Robinson). She will be hosting 'Looking Ahead' at The School of Life next Monday 16 January 2012. For more information and for tickets click here. A longer extract from the book was featured in The Guardian - to read more click here.