The Hungarian-American polymath who helped invent both the modern computer and the logic of nuclear war — giving quantum mechanics its mathematical foundation, co-founding game theory, contributing the implosion mathematics behind the plutonium bomb, and writing the stored-program design that became the blueprint for nearly every computer since.
John von Neumann did foundational work in pure mathematics, then gave quantum physics its rigorous framework, then co-founded game theory and reshaped economics, then helped make the atomic bomb explode, then wrote the design for the machine you are reading this on. Other geniuses said he was the fastest mind they had ever met. He used that mind to help build the computer and the logic of nuclear war alike, and he died at 53.