Here’s what Ayn Rand said about the Gault quote in a Playboy interview in the 70s:
<<PLAYBOY: In Atlas Shrugged your hero, John Galt, declares, “I swear – by my life and my love of it – that I will never live for the sake of another man, nor ask another man to live for mine.” How is this related to your basic principles?
RAND: Galt’s statement is a dramatized summation of the Objectivist ethics. Any system of ethics is based on and derived, implicitly or explicitly, from a metaphysics. The ethic derived from the metaphysical base of Objectivism holds that, since reason is man’s basic tool of survival, rationality is his highest virtue. To use his mind, to perceive reality and to act accordingly, is man’s moral imperative. The standard of value of the Objectivist ethics is: man’s life – man’s survival qua man – or that which the nature of a rational being requires for his proper survival. The Objectivist ethics, in essence, hold that man exists for his own sake, that the pursuit of his own happiness is his highest moral purpose, that he must not sacrifice himself to others, nor sacrifice others to himself. It is this last that Galt’s statement summarizes.>>
and, about Hitler:
<<PLAYBOY: In Atlas Shrugged, one of your leading characters is asked, “What’s the most depraved type of human being?” His reply is surprising: He doesn’t say a sadist or a murderer or a sex maniac or a dictator; he says, “The man without a purpose.” Yet most people seem to go through their lives without a clearly defined purpose. Do you regard them as depraved?
RAND: Yes, to a certain extent.
PLAYBOY: Why?
RAND: Because that aspect of their character lies at the root of and causes all the evils which you mentioned in your question. Sadism, dictatorship, any form of evil, is the consequence of a man’s evasion of reality. A consequence of his failure to think. The man without a purpose is a man who drifts at the mercy of random feelings or unidentified urges and is capable of any evil, because he is totally out of control of his own life. In order to be in control of your life, you have to have a purpose – a productive purpose.
PLAYBOY: Weren’t Hitler and Stalin, to name two tyrants, in control of their own lives, and didn’t they have a clear purpose?
RAND: Certainly not. Observe that both of them ended as literal psychotics. They were men who lacked self-esteem and, therefore, hated all of existence. Their psychology, in effect, is summarized in Atlas Shrugged by the character of James Taggart. The man who has no purpose, but has to act, acts to destroy others. That is not the same thing as a productive or creative purpose.>>