Beyond the currently unknown are the things that are inherently unknowable. Few unknowables are consciously recognized as such. The outcome of a spinning roulette wheel and the local weather three months from now belong to that small class. Every day, however, we bump into phenomena that may well be unknowable but that we do not recognize as such. Some of these unknowables form the bases of respected professions.
Brokers make a living anticipating the fluctuations of stock prices.
Presidents run for office based on claims of what they will do for a vast and poorly understood economy composed of many unpredictably interacting sectors. We do not even know if we are dealing here with the partly known, the mainly unknown or the unknowable. Nevertheless, we unconsciously recognize that the unknowable surrounds us. Nobody thinks about or pretends to know who will run for president 20 years from now. Nor do people try to predict the automobile accidents they will be involved in.