Dan Brown has another hit. The setting of this historical fictional novel is Venice, Florence, and Istanbul. The major theme of the novel is the ethics of controlling the population of the world.
While this novel has a lot of historical sites, as do many of Dan Brown's novels, readers did not feel as though this one had a religious foundation as many others do. Instead, the scientific background teamed up nicely with ethics regarding the ability to control the growing population and even pushing the question if it should be considered.
The idea of overpopulation brings out the primitive nature in people: survival of the fittest. The character who comes up with the way of controlling the population is ingenious because it is through the idea of sterilizing people.
The idea of Transhumanism (engineered genetics) took readers to discussing Hitler and his ideas. Tampering with genetics messes with the balance of the world because there is no real utopia, even though there are people who are constantly striving to find it.
The idea of "Stepford" people is intriguing, yet diversity makes our society function and ultimately, it provides for interesting and unique viewpoints. While it may seem humane, in reality, it ultimately takes away humanity.
While overpopulation might ultimately be the extinction of the human race, a perfect world or human race would breed close-mindedness, which brings on wars and destruction.
Brown's use of Dante's Divine Comedy, specifically Inferno, had readers wanting to read Dante's works as well.