How much thought should go into our decisions? How long should we wait? It is a commonly held belief that the more we think about something, the better our decision will get. Many of us will ponder a decision for hours or even days. However, as shown in research by Dijksterhuis et al, over-thinking a problem can actually result in a worse decision. This does not advocate a spur-of-the-moment impulse decision. Instead, the research advocates the process of unconscious thought: We give the problem time to be mulled over in the back of our mind, but we do not actively think about it. In situations involving complex decisions, unconscious thought is found to outperform its more logical and analytical counterpart.
The experiments performed by Dijksterhuis et al required subjects to make a decision, such as choosing which brand of an item to purchase, using either conscious thought or unconscious thought. For the conscious thought experiments, the subject simply pondered the choices for a certain amount of time and then made a decision. For the unconscious thought experiments, the subject instead gave his or her attention to a distracting and unrelated task for the same amount of time, and then made a decision based on “gut feel”. Subjects were later required to evaluate their overall satisfaction with the decisions. The results found that with simple decisions, subjects using conscious thought did better. However, for complex decisions, unconscious thought was more effective.
A simple decision is one such as choosing which toothpaste to buy. Here, conscious and analytical thought is appropriate. For example, to choose toothpaste, we may first pick out those that contain fluoride. Of these, we either keep or discard those that are whitening. Of the remaining options, we evaluate the prices, and choose the most cost-effective. The decision is simple, and conscious thought works well.
In contrast, a complex decision has many attributes. Suppose we are choosing an apartment. We must consider the location, the amount of room, the lighting, bench and cupboard space, as well as shower pressure, carpet, security, and of course cost. How can we evaluate all these things? Here, the research shows it is best not to try. By simply engaging our attention in a completely different task for a while, we allow our unconscious mind to process the information, and produce a “gut feel” for the best decision. Why is this better than conscious thought? The hypothesis is that complex decisions contain too much information for conscious thought to handle, and thus any choice based on conscious thought will only use a subset of the information. Unconscious thought, on the other hand, is very good at processing large amounts of information. The age-old advice of “sleep on it” contains much truth.
As a final note, the experiments involving complex decisions also included a third group that were required to make their decisions immediately. This group performed worse than the group using unconscious thought. Thus the time to mull it over is important. Impulse decisions are not the way to go.
The research has important implications for our lives. It tells us not to waste too much time going over the same points again and again in our heads. Instead, we bring the key issues to mind, and then relax and give ourselves some time to absorb it. Many of us do this already – we are often reluctant to rush into a decision before “sleeping on it” – however we also waste a lot of time agonizing over the pros and cons. Clearly some analytical thought is necessary. For starters, we must take the time to think through all the information we have. We may also put in our necessary conditions, such as a price cap on how much we can spend. However, when it comes to evaluating and weighing up all the information to make our final choice, unconscious thought has a lot to offer.