Quotes from book
Galileo's Dream

Galileo's Dream is a science fiction novel with elements of historical fiction written by author Kim Stanley Robinson. It describes the life of 17th-century scientist and astronomer Galileo Galilei, and the far-future society living on the Galilean moons he discovered.

“One of the chief features of incompetence was an inability to see it in oneself.”
Source: Galileo's Dream (2009), Ch. 13, p. 295

Source: Galileo's Dream (2009), Ch. 15, p. 354; note: though this statement is incorporated into the story as one Galileo spoke, it is actually a quotation of one he historically made in his Dialogue Concerning The Two Chief World Systems http://www4.ncsu.edu/~kimler/hi322/Dialogue-extracts.html as translated by Stillman Drake.

“The sky itself is the eighth color of the rainbow, spread over the whole sky for us, all the time.”
Source: Galileo's Dream (2009), Ch. 15, p. 354

Source: Galileo's Dream (2009), Ch. 13, p. 280
Context: We all have seven secret lives. The life of excretion; the world of inappropriate sexual fantasies; our real hopes; our terror of death; our experience of shame; the world of pain; and our dreams. No one ever knows these lives. Consciousness is solitary. Each person lives in that bubble universe that rests under the skull, alone.

For anyone who had experienced just once the understanding of one single thing, thus truly tasting how knowledge is accomplished, would then recognize that of the infinity of other truths, he understands nothing.
Source: Galileo's Dream (2009), Ch. 15, p. 354; note: though this statement is incorporated into the story as one Galileo spoke, it is actually a quotation of one he historically made in his Dialogue Concerning The Two Chief World Systems http://www4.ncsu.edu/~kimler/hi322/Dialogue-extracts.html as translated by Stillman Drake.