sentences:  A "logic" is a computer-like device described as looking "like a vision receiver used to, only it's got keys instead of dials and you punch the keys for what you wanna get".In the story, a logic whom Ducky names Joe develops some degree of sapience and ambition.Joe proceeds to switch around a few relays in "the tank" (one of a distributed set of central information repositories), and cross-correlate all information ever assembled – yielding highly unexpected results.