Editing Robots and Empire (section)

==Plot summary==
The Earthman [[Elijah Baley]] (the [[detective]] hero of the previous ''Robot'' books) has died nearly two centuries earlier. During these two centuries, Earth-people have overcome their [[agoraphobia]] and resumed [[space colonization]], using faster-than-light drive to reach distant planets beyond the earlier "Spacer" worlds. Their inhabitants, calling themselves "Settlers" rather than "Spacers", revere Earth as their mother-world.

Baley's memory remains in the mind of his former lover, [[Gladia Delmarre]], a long-lived "Spacer" who uncharacteristically relocated from the spacer world of [[Solaria (fictional planet)|Solaria]] to [[Foundation universe#Aurora|Aurora]]. Gladia's homeworld and the 50th-established of the Spacer planets, Solaria,  has become empty of all human inhabitants, although millions of robot servants remain. A seventh-generation descendant of Baley's, Daneel Giskard ('D.G.') Baley, gains Gladia's help in visiting Solaria, to investigate the destruction of several "Settler" [[spacecraft|spaceship]]s that made landings there and to capture the presumably unsupervised robots. Gladia is accompanied by the positronic robots [[R. Daneel Olivaw|R Daneel Olivaw]] and [[R. Giskard Reventlov|R Giskard Reventlov]], both the former property of their creator, Dr [[Han Fastolfe]], who bequeathed them to Gladia in his [[will (law)|will]]. R Giskard has secret [[telepathic]] powers of which only R Daneel knows.

At the same time, Daneel and Giskard are engaged in a struggle of wits with Fastolfe's rivals: The [[roboticist]]s Kelden Amadiro and [[Vasilia Aliena]], Fastolfe's estranged daughter. Frustrated by his series of failures, Amadiro accepts an ambitious and unscrupulous apprentice, Levular Mandamus, who plans to destroy the population of the Earth by a newly developed weapon, the "nuclear intensifier", with which to accelerate the natural [[radioactive decay]] in the upper crust of the Earth, thereby making the surface of the Earth radioactive. R Daneel and R Giskard discover the roboticists' plan and attempt to stop Amadiro; but are hampered by the [[First Law of Robotics]],

{{blockquote|A robot may not injure a human being, or through inaction, allow a human being to come to harm.}}

which prevents them from a direct attack on Amadiro. Daneel and Giskard, meanwhile, have inferred an additional [[Zeroth Law of Robotics#Zeroth Law added|Zeroth Law of Robotics]]:

{{blockquote|A robot may not injure humanity, or through inaction, allow humanity to come to harm.}}

It might enable them to overcome Amadiro, if they can use their telepathic perception of humanity to quell the inhibitions of the first law. When Vasilia accuses Giskard of telepathy (earlier created by herself), Giskard is compelled to manipulate her mind to make her forget about his telepathic powers. The two robots locate Amadiro and Mandamus on Earth, at the site of [[Three Mile Island Nuclear Generating Station]] in [[Pennsylvania]]. After Amadiro admits their plans, Giskard alters Amadiro's brain (using the newly created Zeroth Law); but in so doing, threatens his own.

Now alone with the robots, Mandamus claims that his intentions were to draw out the radioactive catastrophe over many decades, rather than the mere years that Amadiro wanted, and Giskard, believing it best for humanity to abandon the Earth, allows Mandamus to do this (resulting in the situation depicted in ''[[Pebble in the Sky]]''), and deprives Mandamus of the memory of doing so. Giskard predicts, correctly, that by forcing humanity into leaving the Earth, vigor will be reintroduced into humankind and the new Settlers will populate space until all the governments of the interstellar colonies form a "Galactic Empire". Under the stress of having violated the First Law (in accordance with the Zeroth Law, but with the predicted benefit to humanity being uncertain), R Giskard himself suffers a soon-fatal malfunction of his positronic brain, but manages to confer his telepathic ability upon R Daneel.