Ap Dijksterhuis et al.: "Contrary to conventional wisdom, it is not always advantageous to engage in thorough conscious deliberation before choosing. "
Researchers do not know exactly why this unconscious deliberation should be so successful. But it is well accepted that our conscious brain can only process a limited amount of information at one time. This could mean that we simply lose the big picture with complex decisions. Dijksterhuis and his team also propose that, although we are unaware of it, our brains are churning through the mass of information involved in a complex decision and sifting out the best option. The study ties in with a growing trend in psychology research over the past 15 years, suggesting that our unconscious mind is more important than we once thought. "A lot of complicated processes occur without our being aware of it," says Daniel Kahneman, an authority on decision making at Princeton University, New Jersey.
But the theory doesn't mean that going purely on impulse is a good idea: you still need some information to mull over before making your decision. Particularly when making potentially life-changing judgments such as whom to marry or which career to choose, experts say, study and deliberation are vital to reveal all the options open to us. "I would not advise people to buy a car or house without making a list," Kahneman says. "You will probably improve your intuitions by making a list and then sleeping on it."