Galt is the most important character in the novel and the driving force behind its action. The strike that he conceives, organizes, and carries out is the book’s central, defining event. But his identity remains a mystery until two-thirds of the way through the novel, lending him a mythical stature. In Galt, Rand has set out to present man in his most ideal form. She describes him as physically beautiful, profoundly brilliant, and enormously accomplished. Not only has he been able to develop a revolutionary motor, he has also created a philosophy of reason and become a statesman capable of leading the world’s most talented men. Most importantly, Galt is unwaveringly rational and deals directly with the objective facts he encounters. In him, rationality and emotion are fully integrated. Though ruled by reason, he is able to express and experience his emotions as well. Just as Rand uses Dagny to shatter the mind-body dichotomy that separates physical pleasure from higher thought, she employs Galt to reject the split between reason and emotion.
Galt represents the main theme of the novel and of Rand’s philosophy: the idea that the mind is the only means by which man can achieve prosperity. The mind is the motive power that drives civilization, just as the motor Galt develops can drive industry. Galt embodies the mind, and the question “Who is John Galt?” is not only a literal question about the mysterious man who has disappeared, but a figurative question as well. The question asks what is the mind? and what happens when the mind disappears? Galt knows that without his mind and the minds of the world’s great thinkers, the motive power of the world will be lost and the motor of the world will stop.