"For twelve years, you have been asking: Who is John Galt? This is John Galt speaking. I am the man who loves his life. I am the man who does not sacrifice his love or his values. I am the man who has deprived you of victims and thus has destroyed your world, and if you wish to know why you are perishing--you who dread knowledge--I am the man who will now tell you."
      From Ayn Rand's Atlas Shrugged

Twelve years prior to this statement, John Galt went on strike--a strike of the mind. Society wanted to leech off of his creativity, his intelligence, his genius. They would not recompense him for his accomplishments, rather they would scorn him for his natural abilities. So he left. Before he left, though, he vowed to stop the motor of the world.

Through fear and uncertainty of the possibility of his statement coming true, society decided to try to ignore John Galt's mere existence, making him a common phrase: Who is John Galt? The term came to be used as an end-all conversational piece, when people are presented with a statement that questions any accepted hypotheses of the day. People didn't want to think any more.

The question eventually came to represent the self-immolation of society. People began to stop thinking, stop questioning, stop progress. As society started falling apart at its seams, people looked to the geniuses, the entrepreneurs, the scientists, the people with ability to carry the burden. But society just devoured these people.

At the point where there was no hope, John Galt returned.

Who is John Galt?

John Galt is the man who could do what he said. John Galt stopped the motor of the world.