How we cite our quotes:
She was speaking with a swift, bright certainty, conscious of nothing but the joy of performing her natural function in her natural world where nothing could take precedence over the act of offering a solution to a problem. (184.108.40.206)
It's interesting that problem-solving, thinking, and hard work are described as Dagny's "natural" functions here. Galt asks people to choose his value system, but it seems that many of his values, and the happiness available through them, are dependent on one's "natural" ability. Are some people just unable to achieve the same level of happiness?
He glanced at her and added slowly, a slight emphasis as sole change in the impersonal tone of his voice, "No one's happiness but my own is in my power to achieve or to destroy." (220.127.116.11)
Choice and personal responsibility are a part of happiness, too. In this novel, happiness is the goal of life, and everyone has to make his or her own.
He smiled, the unchanged, insolent, brilliant smile of his childhood.
She heard herself answering, irresistibly, helplessly, happily:
"Hi, Frisco!" (18.104.22.1683-6)
The theme of childhood comes into play here, as Dagny recalls her childhood with Francisco and greets him happily, despite their recent estrangement.