Intuition is familiarity that we do not recognize – familiarly that we gain at an unconscious level through repeated practice.
Practice is the ability to perform something in a situation that is replicable – such as positions on a chessboard, the arrangement of notes in a famous song, or 100 leaky faucets that have the same problem. With sufficient practice, a chessmaster chooses the best move in a position within a split second. The fingers of a saxophonist push the right buttons to play Take Five with clockwork precision. An expert plumber can fix a leaky faucet with a few cranks of her spanner, and without a second thought.
But not all professions are equally suitable for developing one’s intuition. Take the case of the stock picker, who based on rigorous analysis, projects that a competitor to Facebook is 20% likely to double their revenues next year. For this soothsayer to validate his data, he would have to recreate our world a 100 times and observe in how many of those worlds the competitor succeeds. He operates in what psychologists call a “low-validity environment”. This is true, to varying degrees, of doctors who examine patients with different internal chemistry, of interviewers who examine candidates with different backgrounds and of all varieties of pundits who predict where the stock market is headed.
Before you believe an expert’s intuitive prediction, ask yourself whether she has had the ability to recreate a particular situation 100 times in her profession. The degree to which she can do that is the extent to which you should trust her intuitive judgement.