is the existence of a man from the past brought to the present. He is an "unknown variable" that confuses the SRB machines, making it impossible to accurately calculate the odds. That man is Thomas Cole, who became known as the Variable Man. Cole is a man from 1913, the time just before the First World War. He is accidentally brought into the story's present by a Time Bubble that was used for research about the past. The authorities attempt to capture him but he evades them and goes on the run. It is discovered that Cole has a genius for intuitively understanding and repairing machines, which he used to earn money as a repair man in his own time, and again while on the run. Other characters speculate that such abilities were more common in the pre-WWI era that produced Edison and other inventors. The engineer working on the FTL bomb realizes that the Variable Man might be able to make Icarus work, and manages to track him down. Cole agrees to help on the understanding that he will then be sent back to his own time with a quantity of precious metals to buy equipment for his repair business. Cole eventually succeeds and an Icarus device is launched towards Proxima Centauri, with the intention of destroying the star along with its planets while Earth's fleet attacks the empire's forces in space. The device fails to affect its target, leading to a crushing defeat for Terra. Investigation reveals that the star did not explode because Cole had made the Icarus device function fully according to its inventor's intentions, solving the problem that had destroyed the prototype. Instead of a powerful bomb, humanity now has a working FTL drive that cannot be intercepted by the Centaurans. The Terran authorities realise they are now free to travel beyond the limits of the Centauran Empire and there is no further need for war. References External links add Standard Ebooks link Fiction set around Proxima Centauri Short stories by Philip K. Dick 1953 short stories Works originally published in Space Science Fiction