This book is the last of the Robot Series. Lots of spoilers follow.
At the end of the The Robots of Dawn, we learn that one of the main robots (Giskard) is telepathic. His exact abilities are somewhat unclear. He can’t read thoughts, but he can read emotions and he can alter thoughts and memories.
In previous reviews, I’ve noted that Asimov’s books are mostly focused on robotic ethics. Also, in previous books, the universe was saved by the combination of man (Elijah Baley) and robot (Daneel, a humanoid robot and, later, Giskard).
In this book, the ethical dilemmas come to climax.
Baley is long dead, leaving Daneel and Giskard to save the universe on their own.
Daneel, who is increasingly able to reason like a man, figures out that the three laws of robotics are incomplete. It’s insufficient for robots to follow only the first law, which says, "A robot may not injure a human being or, through inaction, allow a human being to come to harm." Daneel instead reasons out the zeroth law, which he believes is a corollary of the first law. The zeroth law states, " A robot may not harm humanity, or, by inaction, allow humanity to come to harm."
Since the zeroth law takes precedence over the first, it follows that a robot can harm a human if doing so will save humanity.
In the series so far, robots have generally been a force for good. With the introduction of the zeroth law and Giskard’s telepathic ability, the reader begins to get the sense that robots may not quite so unambiguously good after all.
Indeed, the book ends with Giskard saving the Earth from immediate destruction but choosing to allow a man to make the Earth uninhabitable over a slow and easily detectable process. Giskard does this because he believes doing so will be the best for humanity. We see, therefore, that even the simplest, most objective ethical framework imaginable ends up leading to some rather . . . uncomfortable results.
Before ending, I should note that the first and last books in this series were written more than 30 years apart. It’s pretty impressive that Asimov managed to make it all fit together and that he doesn’t seem to lose anything in his writing ability over such a long time.
On to the Galactic Empire Series.