"What is character but the determination of incident? What is incident but the illustration of character?"

Henry James is recommending that character and occurrence are intertwined and inseparable. Character is the determination of incident, indicating that the actions of a character are identified by their character and characteristics. Event is the illustration of character, suggesting that the occasions that happen in a story are a reflection of the character's character. To put it simply, the occasions that happen in a story are a result of the character's character and characteristics. This quote suggests that character and occurrence are 2 sides of the very same coin, and that one can not exist without the other. It is through the combination of character and occurrence that a story is produced and the audience is able to understand the characters and their inspirations.