The mathematics of uncertainty — which transformed how civilization manages risk, enabled the insurance industry, statistical medicine, quantum mechanics, and machine learning, and produced an intellectual foreclosure that made prior frameworks for reasoning about uncertain futures permanently inadequate
Before probability theory, uncertainty was managed through divination, prayer, experience, and judgment. Floods came or they didn't. Voyages succeeded or they didn't. There was no formal language for expressing "this is more likely than that" in a way that could be computed, combined, or traded. In 1654, Blaise Pascal and Pierre de Fermat exchanged a series of letters about how to divide gambling stakes in an unfinished game. The mathematics they developed to answer that question became the foundation of the modern insurance industry, statistical medicine, quantum physics, and machine learning.