ABSTRACT
Often the most learned, wise, and scholarly persons appear foolish when making long-range predictions about the future. This is particularly true if their predictions are widely known by others and examined over a prolonged period. The hazards are based on the fact that a large number of interrelated variables must be taken into account in making any projection. Each of these variables can move in any of a variety of directions, and therefore none is entirely predictable. Since no one can perfectly predict changes over time in any of these variables, to predict how the entire group is going to be altered is even more hazardous.
