"A bullet grazed the top of your skull and most likely gave you a concussion. You’re very lucky to be alive. An inch lower, and..."
This quote is important because it's when Sienna first tells Robert what happened to him, she tells him that a person shot him. Later, it was revealed that Robert was never in any danger nor he was shot. Sienna's description of Robert's accident was used as tool to manipulate him into believing that he was in danger, so he would work for the Provost instead of the W.H.O.
"Robert. The U.S. government just sent someone to kill you."
Sienna caught a glimpse at Vayentha, who arrived at the apartment building right after Robert called the U.S. Consulate. Sienna told him that the United States government sent her to kill him. It was later learned that Sienna and the Provost had hired her to keep Robert away from the authority.
"Dr. Sinskey, you talk about controlling epidemics as if it’s a good thing."
This quote occurs during the meeting where Zobrist tells Sinskey about his ideas about an epidemic in which it controls the human population. He began criticizing Sinskey's work in the W.H.O. since they are doing an excellent job with controlling these epidemics. Zobrist thinks that a new plague would be good since it would allow the human population number to decrease to a number that is sustainable for the planet to hold.
"The disease is overpopulation. And unless we face world population head-on, we are doing nothing more than sticking a Band-Aid on a fast-growing cancerous tumor."
Zobrist's comparison of the overpopulation to cancer made Sinskey feel sick and disturbed. It allowed the readers to make sure that Sinskey was never on board with Zobrist's line of thinking and felt disgust to even think of him.
"When Sienna read Zobrist’s description of what he had created, she was horrified. She wanted to stop him. She considered his virus so dangerous that she didn’t want anybody to gain access to it, including the World Health Organization. Don’t you see? Sienna has been trying to destroy the virus... not release it."
Robert Langdon takes Dr. Sienna Brooks back to Elizabeth Sinskey. He tries to explain to Sinskey that instead of working against them, Sienna was working independently with them. She knew that people would think that she was working with him since she was his lover, but from the moment she learned of Zobrist's creation she wanted to put a stop to it.
"Ms. Brooks, I may disagree with Bertrand’s methods, but his assessment of the state of the world is accurate. This planet is facing a serious overpopulation issue. If we manage to neutralize Bertrand’s virus without a viable alternate plan... we are simply back at square one."
This comes to a surprise for Sienna, who just learned that Elizabeth now accepts the virus now that it's out there. Elizabeth accepts that the overpopulation is a problem in the planet and fixing Zobrist's creation would just bring them back to the problem. Elizabeth does admit that she disliked how Zobrist executed and managed to solve the population problem.
"If we don’t embrace them, then we are as undeserving of life as the caveman who freezes to death because he’s afraid to start a fire."
Sienna tells Sinskey of what she thinks about genetic engineering. It's to her belief that humans are responsible in doing everything that is possible to save the human race, even if some of these things are incorrect.
"Dante’s poem, Langdon was now reminded, was not so much about the misery of hell as it was about the power of the human spirit to endure any challenge, no matter how daunting."
In the end of the novel, the narrator tells the readers that Robert Langdon saw the story of The Divine Comedy as a story of hell and damnation. However, he now has a new way of seeing it. For him, it is also a story about the ability of the human race to overcome the many challenges that face them in their daily life.
