Foundation and Earth, by Isaac Asimov (pub. 1986)
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Caution: I will assume that if you are reading this book, you will have already read the previous one. Therefore, anything about that book which I avoided spoiling in its review, should not constitute a spoiler for you at this point, and may be mentioned here insofar as it doesn't spoil this book... But there will also be some spoilers of this book at the very end of the review.
So, this, the fifth book of the Foundation series (though you may see it called the seventh, by sources which place the two prequels which were written later as the first and second books), is a direct sequel to the fourth book, "Foundation's Edge." There are a couple of things I avoided spoiling in my review of that book, but I'll reveal them now. First of all, the planet Gaia is a single super-organism. That is, everything, including the people, animals, plants, minerals, microorganisms... everything, is all connected, part of a whole. There is a collective consciousness, to which every part of Gaia contributes, though obviously only the humans possess intelligence. Still, every aspect of the ecosystem is planned, in perfect balance, and all life is considered sacred, though obviously death is necessary, as part of the cycle of life, and all that. Anyway, it's complicated. But people do retain a certain level of individuality, as well as being part of the whole... and may sometimes speak as themselves, and sometimes as Gaia (which leads to a complicated system of personal pronouns).
Another thing I need to mention is that it was established that Golan Trevize, the central character of that book and this, has a certain knack for "rightness." That is to say, an intuitive ability which occasionally allows him to make the right decision, without consciously understanding why he chose it or why it's right. It is because of this ability that Gaia chose him to make a decision. They wanted to work toward a state of Galaxia, that is, making the whole Galaxy a single super-organism of the same kind that Gaia is. But they were unwilling to impose their will on the galaxy of their own volition, and so, they required Trevize, and while they have mentalic abilities superior to those of the Second Foundation, they would leave his mind completely untouched. And in the crucial moment at the climax of the fourth book, when forced to choose between the First Foundation, Second Foundation, or Galaxia, Trevize chose Galaxia.
However, he wasn't comfortable with his decision. He has no desire to give up his individuality, so he wants to figure out why he chose as he did. I'll tell you this right now, as far as I can tell, there is never any explanation given for his intuitive ability, unless I missed something. So I guess we just have to accept it and move on. At any rate, the fifth book picks up not long after the fourth, with Golan Trevize and his friend Janov Pelorat still on Gaia. Trevize soon leaves on his ship, the Far Star, accompanied by Pelorat and Bliss (the two of whom had established a romantic relationship in the previous book). Another mystery continued over from the previous book was the fact that all information about Earth and its location had been removed from all the records in the galaxy, including both the great library of Trantor, and the collective memory of Gaia itself. Trevize believed that if Earth went to such lengths to hide itself, then finding it was of vital importance to figuring out why he chose Galaxia.
I'd rather not divulge too many details of their search, but their first stop is Comporellon. Here they learn the coordinates of three Spacer worlds, which ties in to Asimov's Robot Novels, which were set 20,000 years prior to the Foundation series. Originally, Earth colonized 50 planets, but there was eventually conflict between Earthers and Spacers (the settlers of those worlds), and later there was a second wave of settlers from Earth (this time without robots), who settled a number of new worlds, which themselves eventually settled other worlds, and so on, until thousands of years later, by the time of the first Galactic Empire, there were millions of inhabited planets, and by the time the Empire was falling thousands of years after that, no one remembered the planet of origin anymore. By the time of "Foundation and Earth," there were only legends, scattered around the galaxy, but most of them claimed Earth was either unfindable, or completely gone, or most commonly of all, that it was radioactive and uninhabitable. Of course, few people if any even knew of the original 50 Spacer worlds, which were not a part of the Empire.
And so, Trevize, Pelorat, and Bliss set out to find these three Spacer worlds. The first was Aurora, which provided no clue to Earth's location. The second was Solaria, which also was of no help, however, there they picked up a young Solarian named Fallom, who was, like all her people, a hermaphrodite, and considered people with single genders to be only half-human. (However, Trevize and the others decide to use feminine pronouns to describe Fallom.) Fallom had never met another human (or Solarian) in person, she only knew her robot, Jemby. For the rest of the book, even as she grew closer to Bliss and Pelorat (though not so much Trevize, whose special sense made him uneasy about her presence on the Far Star), she always hoped to return to Solaria, and Jemby.
After Solaria, they visit Melpomenia, where they learn the coordinates of the remaining 47 Spacer worlds, though they won't have to go to any of them. They manage to estimate where Earth would be, and head there... however, instead of Earth, they find a world called "New Earth," which had been directly settled by Earth long ago. However, they eventually do find Earth, and more importantly, its Moon. But this is toward the end of the book, and I don't want to give away any spoilers about it... just yet. I will, however, do so later in this review, the reason being that this is, in essence, the end of the Foundation series, all future books being prequels. (Therefore, I can't very well save my spoilers about this book for future reviews, as I normally do.)
But before moving on to those spoilers, I should mention some other things. Like the fact that throughout the book, Trevize and Bliss frequently debate the relative merits of Gaia vs. "Isolates," i.e., humanity as it currently exists in most of the galaxy. It is, essentially, a friendly debate, and in fact, on more than one occasion, Trevize and Bliss specifically make overtures of friendship toward each other (mostly because of their common affection for Pelorat). However, there are also a good number of instances where their points of view on other matters stand in stark contrast, making them... not so friendly. Another matter I need to mention is a flash of insight Trevize had at one point that there must be a fundamental flaw in the Seldon Plan. While Trevize, as all First Foundationers, has no real understanding of the Seldon Plan or psychohistory, beyond the two basic axioms: one, that there be a large enough number of humans to be treated statistically; and two, that human beings not know the specific conclusions (i.e., the various "Seldon Crises") predicted by psychohistory before they have come to pass. Trevize speculated that there is a third, more fundamental axiom which no one had ever considered, which could completely derail the Plan. What that third axiom might be is another thing he's searching for, along with the mystery of Earth and his decision regarding Galaxia.
Well, anyway, it's a good book, but I'd almost prefer it (and the preceding one) not to be part of the Foundation universe, but rather to stand on their own. As I say time and again, I love the whole concept of the Seldon Plan, and would have simply enjoyed seeing a series entirely devoted to exploring the various Crises which eventually lead to the establishment of the Second Galactic Empire. Of course, this book is a necessary follow-up to the fourth book, and in fact, the way it ends necessitates at least one more follow-up (which doesn't exist) to get things back on the original path. I mean, at this point the first and second Foundations are still following the Seldon Plan, oblivious to everything that's going on which could ultimately make everything they've done for the past 500 years irrelevant... and there are no guarantees that the things described in the fourth and fifth books will actually come to pass, though I believe some things in the prequels (which at this point I've yet to read) will help clear up any seeming discrepancies between the ideas of these books and the first books. So... I don't know. I definitely look forward to reading those prequels (Asimov's as well as those of other authors in this series), plus of course the various other series that have been tied together, including the Robot novels, the Empire novels, and "The End of Eternity" (which I think is not part of a series, though I could be wrong- and it's clearly tied into this series). Anyway... aside from my desire for pure "Seldon Plan" stories, the fourth and fifth books are definitely interesting in their own right. I wish I could think of more to say, but I suppose I'd have to rate them higher on their own merits than I do as part of the Foundation series as a whole. Then again, there's nothing wrong with introducing a different line of thinking that could potentially change everything. A little uncertainty is actually a good thing, a bit of spice, especially in a series where the ultimate conclusion is supposedly foregone, and all the major events of history for 1000 years have been predicted. Yes, such a series can do with a bit of dramatic tension, I suppose... Even so, I still want to eventually arrive at the foregone conclusion, and it bothers me that Asimov will never get to write it. (But hey, I'd dearly love to take a stab at it myself, someday.) And I guess that's all I can say, for now, by way of review....
And now for some spoilers.
So, as I said, Trevize and the others finally find Earth. And it is, as they've heard at virtually every step of their journey, radioactive and uninhabitable. However, Trevize later guesses that whatever of Earth has been hidden, might be found on the Moon. Or rather, under the surface of the Moon. Bliss does a mentalic scan and eventually locates a consciousness which is neither human nor robotic, which seems to be welcoming them. Entering the Moon, they meet Daneel Olivaw, a humaniform robot who has been active for 20,000 years (though in that time every part of him has been replaced numerous times, including his positronic brain). He is a familiar character to anyone who's read the Robot novels, of course. He informs Trevize and Pelorat that he was responsible for a number of things, including the founding of New Earth and Gaia, as well as the development of psychohistory, and that robots which were working with him had removed information about Earth from the galaxy's records. And while waiting to find someone like Trevize, who could make the choice about Galaxia, time has grown short. Daneel won't last much longer, and cannot make a sustainable new brain for himself. He needs to fuse his brain with that of a human, and he has chosen Fallom, whose Spacer heritage would allow him to live a few more centuries (as well as utilizing the transducer lobes Solarians have developed in their brains, which allow them to control the flow of power). This time is necessary for him to oversee the development of Galaxia.
Meanwhile, Trevize has finally accepted that Galaxia is necessary. He has realized that the third axiom essential to psychohistory is that humans are the only intelligent beings in the galaxy. Which (because of the events of "The End of Eternity," which I haven't read), is in fact the case. However, there could be intelligent beings in other galaxies, which might someday invade our galaxy, and without Galaxia, humanity would be divided against itself, making it easy for invaders to dominate. However, there is also the insinuation that Fallom is, herself, different from humanity. Which means that, while her fusing with Daneel might be humanity's only hope against invasion from without, they might also represent an internal threat to humanity. That's barely hinted at, but it would likely be the subject of a subsequent novel, if there was one. Which, of course, there's not....