All the main positive characters in Atlas Shrugged are great minds. Dagny Taggart is a brilliant businesswoman/engineer who runs a transcontinental railroad superbly. Hank Rearden is a productive genius of the steel industry and an extraordinary metallurgist who invents a new material that's vastly superior to steel. Francisco d'Anconia is a prodigy who masters every task as quickly as it's presented to him, independently develops a crude version of differential equations at age 12, and invents a new kind of copper smelter. Ellis Wyatt is an innovator of the oil industry who creates an advanced method of extracting oil from shale rock. Ragnar Danneskjöld is a brilliant philosopher, and Hugh Akston, his teacher, is the last great advocate of reason. Above all towers John Galt, a philosopher, scientist, inventor, statesman, and man of superlative genius and accomplishment who, in real life, can be compared only to the greatest minds of human history. The heroes in Atlas Shrugged all dramatize the novel's theme: The mind is mankind's tool of survival.
In Atlas Shrugged, every advance that makes human life on earth possible is a product of the reasoning mind. The creation of the John Galt Line requires Dagny's engineering knowledge, the creation of Rearden Metal requires Rearden's understanding of metallurgy, and the invention of Galt's motor requires his command of physics. All inventions, breakthroughs, and innovations are creations of the mind, including the production of items that human beings require for day-to-day survival. Atlas Shrugged reminds us that the ability to successfully grow food involves knowledge of agricultural science; building houses relies on comprehension of architecture, engineering, and mathematics; and curing diseases requires knowledge of medicine. If man is to resolve various forms of mental illness, he must know psychology. If he is to establish a free society, he must understand the principles of political philosophy. If man is to avert war, or even personal conflict, he must be able to negotiate his differences, which requires reason. Every value that human life depends on is a product of the reasoning mind. This idea is Ayn Rand's thesis in Atlas Shrugged.
The villains in Atlas Shrugged avoid rationality and production, seeking survival instead by looting the producers. The villains attempt to live by brute force, not by reason. However, man is not a tiger or a shark; he can't survive the same way animals do. Animals survive by devouring each other, and nature equips them to battle for survival by exclusively physical means. Each species possesses its survival instrument. Birds have wings, lions have claws and fangs, antelopes enjoy speed, elephants utilize size, gorillas showcase their strength, and so on, but man can't survive by these means. He lacks wings, claws, great size, strength, or speed. Nature endows man with but one instrument by means of which to survive — his mind.
Dagny, Rearden, Galt, and the other thinkers live in accordance with their rational nature. Wesley Mouch, James Taggart, Floyd Ferris, and the other villains in the story seek survival by means of force, which is an animal's method, not a man's. Consequently, the villains have no more chance to succeed than a bird that refuses to use its wings. The looters can — and, at times in real life, do — destroy the creators. But having abandoned their survival instrument, they lack all chance of achieving flourishing, joyous lives. Once they ruin the producers, they are left to starve. Only the men of the mind can attain prosperity.
In order to fully understand Ayn Rand's theme in Atlas Shrugged, we must contrast it with its opposites. Objectivism's claim that the mind is the fundamental means by which man survives contrasts with the claims of the two dominant philosophical schools of modern western culture, Marxism and Christianity. The Marxists maintain that manual labor is the means by which human beings produce economic value: Muscle power, not brain power, creates wealth. Marxists believe that the physical workers create economic commodities and the capitalists exploit the workers. Ben Nealy, the contractor with whom Dagny is stuck after McNamara's retirement, expresses Marx's belief succinctly when he claims, "Muscles, Miss Taggart, that's all it takes to build anything in the world." Ayn Rand's answer to Marx is contained on every page of Atlas Shrugged. How much manual labor (muscle power) does it take to create Galt's motor, Rearden's Metal, or Wyatt's innovative process of extracting oil from shale? In real life, how much muscle power was required to invent Edison's light bulb, design Frank Lloyd Wright's buildings, discover methods for heart transplant surgery, or create Fulton's steamboat? Obviously, no amount of muscle power is sufficient to create these products on its own, because they first require breakthroughs in knowledge. The mind is fundamentally responsible for these innovations and countless others. Manual labor is part of constructing new products after they're designed, but the brain performs the original act of design, not the biceps.
Christianity's view is that man survives by faith in God — that strong, pure faith can move mountains. But Ayn Rand argues that all the faith in the world is inadequate to move one grain of sand one millimeter. If human beings seek to move mountains in order to construct interstate highway systems or transcontinental railroads, they can do so only by means of dynamite, technology, and science. Faith in God cannot enable Dagny and Rearden (or their real-life equivalents) to build railroad lines, invent metals, or design new bridges. Only rigorous thought can reach such accomplishments. The mind — not faith in the supernatural — grows food and cures diseases. Likewise, only societies that are scientifically, technologically, and industrially advanced — such as the modern United States — have high living standards. Places and eras dominated by faith, such as Europe during the Middle and Dark Ages, are backward and destitute. When the mind is absent — whether on strike, as in the novel, or subordinated to faith, as in Medieval Europe — the result is regression into a cultural dark age.
Great creative minds such as Galt's, by definition, think new thoughts and discover new knowledge. They neither conform to social belief nor obey a tyrant's command. They follow their own vision and pursue their own truth. In making intellectual breakthroughs, people like John Galt lead mankind's progress. This idea, too, is part of Ayn Rand's theme in Atlas Shrugged: The mind must be free. Galt's strike is a declaration of independence for the intellectual. The strike shows that the mind can't and won't function under compulsion. Freedom is required for Rearden to create his metal, for Galt to invent his motor, or for any innovator to discover new truths. The creative mind looks only at the facts, whether of metallurgy, energy conversion, or another field. It does not bow to the whims of a dictator. If people like Floyd Ferris or Wesley Mouch can, by decree, stifle or redirect the research being done by a Galt or a Rearden, they've placed a gun between the great mind and the facts that it studies. This explains why the freest countries are the most advanced, and why the brutal dictatorships that proliferate across the globe wallow in backwardness and abysmal poverty. Galt's strike recognizes that the first right of human beings is the freedom to think and act independently. The result of this freedom is the unshackling of the human mind and a dramatic rise in living standards.