The Fabric and the Brain

The essay argues that AI personalities are central to designing agent ecologies, and that only high-personality ecologies of distinct but mutually intelligible entities can be economically generative. It proposes "HX design," designing the personalities of ghosts in machines, as a way to make complex technologies predictable and composable rather than opaque. Its examples include the "optimistic" rollups on Ethereum, the scheduling heuristic Shortest Processing Time, which can delay long tasks indefinitely, and how an agent's behavior imposes costs that counterparties must absorb.