Modern society attempts to predict all manner of future events, from the course of hurricanes to oil prices to asteroid impacts-in order better to prepare for them. But, in a complex world, accurate predictions are often surprisingly hard to come by. Just prior to Y2K, for example, western Europe was ravaged by a storm that took weather forecasters by surprise, and caught tens of millions of people unprepared.
Prediction is central to the scientific method.
Many scientific hypotheses are in fact predictions that can be tested under controlled experimental conditions. For example, a biologist might hypothesize that a certain gene controls appetite in rats. The biologist can test this idea by removing or altering this gene in laboratory rats, and seeing if the eating behavior changes. Once the prediction is confirmed, it can be applied to real-world problems, perhaps, for example, gene therapy for appetite suppression in humans. But predictions about the real world are different from those that apply to experimental conditions.