Episode 12: A Machine Must Know Its Next MoveEpisode 12 is built around a deliberately small, visible control cycle: a fixed 'Target', a revisable 'Candidate', a comparator, a lawful next action, a verified write, and a halt. Its artwork functions as a technical plate rather than an ornamental cover, keeping the distinct roles and forbidden shortcuts in view. A comparison is evidence, not a write; a write is not established until it has been verified; and a desired display is not enough unless the route to it can be reconstructed. The episode also returns to Trakhtenbrot’s labyrinth algorithm—structurally a branching maze in contemporary terms—to show what additional memory, deterministic choice, and bounded failure mean when a controller must search rather than follow one fixed cycle. The claim is not that the controller has judgment or general intelligence. Its virtue is narrower: it can act only within a named authority, refuse an unauthorized action, name error and halt, and leave a trace that another person can inspect.