In the short story “A Sensitive Dependence on Initial Conditions,” the radical science fiction author Kim Stanley Robinson reimagines the atomic bombing of Hiroshima and Nagasaki. What might have happened, he asks, if the “sufficient conditions model of historical explanation” had prevailed? A welder is hungover, resulting in a structural defect to the Enola Gay that causes the plane to crash during a demonstration. The captain of the replacement crew has a crisis of conscience and deliberately misses Hiroshima. Both Hiroshima and Nagasaki are spared, setting off a chain of events that lead to President Harry Truman losing his reelection, a negotiated settlement preventing the Korean War, and the banning of nuclear weapons in 1956.

Robinson’s story continues. He refashions the events according to other principles — “the necessary conditions model,” “the weak covering law model,” “the great man theory,” “the butterfly effect,” “the strong covering law model” — and imagines the outcomes: conflict in the Middle East triggers World War III in 1956; nuclear deterrence settles the Korean War in 1950, making it the last large conflict of the twentieth century; a nomad in Central Asia steps on a butterfly in 1945, resulting in the rise of the Hiroshima Peace Party, Palestinian statehood, and, perhaps, the birth of a second Christ by 1990.

The principles and their products appear to trap readers in a labyrinth of determinism, but Robinson ultimately holds out hope for human intervention. The last iteration of the events tells us: