In Foundation and Earth, Isaac Asimov answers one burning question left over from Foundation’s Edge and, indeed, the entire Foundation series: Where’s Earth and what happened to it? The answer nearly kills Golan Trevize and his companions, Foundation historian Janov Pelorat and Bliss, who is part of the living planet Gaia. In Foundation’s Edge, Trevize made a decision that put humanity inexorably on the path to becoming Galaxia, a galaxy-wide organism in which everything, even the people, are part of its consciousness. Gaia, originally thought to be Earth and the homeworld of the Mule, is a planetary version of this. Bliss is an individual, but she is also Gaia. But Trevize is worried. He believes he has destroyed the Seldon Plan, the psychohistorical calculation that will result in a second empire to replace the fallen Galactic Empire. Trevise was raised on the belief the Foundation would be the nucleus of this new empire. Now, he thinks he’s changed all that, and he wants to know why.
To do this, he sets out to find Earth, the almost mythical world where the human race began. Before heading for the so-called Spacer Worlds, the first worlds ever settled by humans, they nearly lose their ship on Comporellon, a world so old that some of these worlds are in its historical records. Trevize “negotiates” his way out of his predicament and heads for three worlds Aurora, Solaria, and Melpomenia, where they discover a fourth, Alpha. Each visit nearly kills them. They are almost wiped out by feral dogs, a particularly aggressive form of moss, and xenophobic natives.
Like Foundation’s Edge, Foundation and Earth solidifies the ties between Asimov’s Foundation and Robot series. It’s even suggested that the Galactic Empire destroyed Earth because it and the spacer worlds used robots. The “primeval” history of humanity is fascinating, but the story is mostly dialog. Orson Scott Card once said talk is Asimov’s action, but there was a lot more of it in this story. That makes this one the weak sister of the series, but one definitely a must read for those who’ve read the rest of it.