Brave New World explores the classic conflict between the individual and society. In this particular case, personal identity has been sacrificed for the sake of a common good. A form of biological reproduction produces certain types of humans in batches – 96 identical copies of the same being. A social "caste" structure separates the citizens into five groups, the result being that a given individual is little more than a faceless, color-coded member of a larger group. Certain characters in the novel grow uncomfortable with this idea, are downright disgusted by it, or for one reason or another find that they just don't fit the mold. They seek to understand their individuality through isolation and self-exploration.
Women in Brave New World are defined only by their function as sexual objects. This is the extent of every female's identity.
It is only by killing himself that John is able to maintain his identity as a human being instead of an animal.