Ancillary Justice constantly raises questions about what it means to be an individual, conscious of one’s existence as a self separate from others. Although Justice of Toren’s existence as an artificially constructed intelligence occupying both a ship and several reanimated ancillary bodies violates most concepts of individuality, Justice of Toren refers to itself as “I.” When the segment that takes the name Breq finds herself isolated in a single body, she experiences this as a loss of self and struggles to adjust. However, even as Justice of Toren, she experienced a kind of fragmentation: One Esk developed its own consciousness before the destruction of Justice of Toren, a process linked to One Esk’s interest in collecting music. However, Anaander Mianaai hastens this fragmentation when she tampers with the ship’s memory, programming it to remember events differently than the way One Esk experienced them.

Anaander Mianaai, the all-powerful Lord of the Radch, experiences an extreme version of fragmentation herself. Her internal conflict about the actions she chose to take against Garsedd initiate a division of her selves. As a result, her selves become opposing forces. The concept of duality manifests within the other characters as well. When Mianaai first tampers with Justice of Toren’s memory, she tells the ship: “You and I, we really can be of two minds, can’t we” (213).