"Atlas Shrugged", published in 1957, was considered Rand's "magnum opus". Rand described the theme of the novel as "the role of the mind in man's existence—and, as a corollary, the demonstration of a new moral philosophy: the morality of rational self-interest". It advocates the core tenets of Rand's philosophy of Objectivism and expresses her concept of human achievement. The plot involves a dystopian United States in which the most creative industrialists, scientists, and artists respond to a welfare state government by going on strike and retreating to a mountainous hideaway where they build an independent free economy. The novel's hero and leader of the strike, John Galt, describes the strike as "stopping the motor of the world" by withdrawing the minds of the individuals most contributing to the nation's wealth and achievement. With this fictional strike, Rand intended to illustrate that without the efforts of the rational and productive, the economy would collapse and society would fall apart. The novel includes elements of mystery, romance, and science fiction, and it contains an extended exposition of Objectivism in the form of a lengthy monologue delivered by Galt.