1. Confronting an alien technology -- Pt. I. First sketch -- 2. From one cell to many -- 3. Making a difference -- 4. Laying down a body plan -- 5. Beginning a brain -- 6. Long division -- Pt. II. Adding details -- 7. Fateful conversations -- 8. Inner journeys -- 9. Plumbing -- 10. Organizing organs -- 11.Taking up arms (and legs) -- 12. The Y and How -- 13. Wired -- Pt. III. Refinement -- 14. Dying to be human -- 15. Making your mind up -- 16. A sense of proportion -- 17. Making friends and facing enemies -- 18. Maintenance mode -- Pt. IV. Perspectives -- 19. Perspectives.