Edward Wilson
As narrator, Wilson is the main character of the book. He is not writing a character-based book, however; his contributions are for personal arguments of persuasion. He does not want his character as a person to dissuade someone from listening to the credibility of his words, so he attempts to base all of his statements upon established fact as far as he can. When that is not possible, he appeals to his own convictions based upon long strings of facts. Basically Wilson is bothered by inconsistency and small-thinking, so he is writing to persuade people to think broader and to consider other fields of discovery when trying to form conclusions about the nature of the universe. He believes in order above chaos.
Gerald Holton
Holton is a physicist and historian who contributed to his respective fields largely during the twentieth century. He posits the "Ionian Enchantment" theory which Wilson explains to mean that the universe operates according to principles of order and consistency.
Marquis de Condorcet
The Marquis gets a shoutout in Chapter 3 for his work in mathematics and social sciences. He advocated for systematic, holistic methods of thought within the scientific fields.
Francis Bacon
Bacon was a scientist -- who also dabbled in the arts -- during the Enlightenment. He established the Baconian method: gathering data in order to analyze it and form conclusions about nature.
Rene Descartes
Descartes believed in the unity and order of the universe, a conviction which led him to make many discoveries relating algebra and geometry to one another. He sought to make more connections between fields in order to better understand the nuances of each respective field.
Isaac Newton
The Father of Modern Physics, Newton plays an important role in Chapter 3. Wilson refers to Newton's connecting the laws of physics with the laws of planetary motion. Newton was attempting to apply local knowledge of physics to extra-planetary physics in order to better understand both.
