A mathematician built the theory that could guide a missile straight to its target. Then he spent years refusing to hand anyone the instructions.

In 1946, an engineer at Boeing wrote to Norbert Wiener asking for a wartime paper he'd written on missile guidance. Wiener said no. He published his answer in The Atlantic the following January, a public letter called "A Scientist Rebels." Giving away scientific information was never as innocent as it looked, he wrote. The moment a paper left his hands, he'd made himself responsible for who it killed.