Top critical review
Your mileage may vary
Reviewed in the United States on December 22, 2019
I'm torn on how to rate this book. It isn't like the first three in writing (not least in losing the header references to the Encyclopedia Galactica), which are very terse (Foundation having been serialized) in the fashion of mid-century sci-fi: this is more like modern science fiction, with more of a focus on characters and so on instead of plot, technology, and twist.
The first two novels are relatively harder science fiction. Second Foundation, with the introduction of mentalics, veers to the soft. I enjoy Seveneves as much as Star Trek, but the change in tone is jarring. This book continues the shift begun in Second Foundation.
It's well-written and gripping for the first two-thirds, but I found the conclusion entirely unsatisfactory. It has something of the Deus ex about it, even though it is nigh as thoroughly hinted as Chekhov's gun.
I have been rooting for the Second Foundation for the entire series, ever since I learned it existed. It fits my bookish and mathematical temperament. In the end of this book, the future under the Second Foundation is described as a 'future from calculation, ruled by calculation, a living death'. It sounds like my kind of future. Even the first Foundation, with its machiavellianism, is tolerable: it is just realpolitik. It is described as 'a rebirth of the first Galactic Empire, born in strife and dying in strife': but it is the first Empire born again.
Instead we are introduced to Gaia, the Mule's home planet, inhabited by a race of Mules comprising a hive mind - including the natural environment, in a sort of Earth/Animal Liberation Front dream - ruled by the hidden hand of remnant robots left over from the first colonization of the galaxy. I can see why the Mule tried so hard to escape it and its influence after a few pages of description, and almost sympathize with his actions now. (By the way, the description of Gaia in this book doesn't fit at all with what the Mule himself tells about his history, so either the Mule was lying or Gaia is: I think it is likely the latter, Gaia is so creepy.)
It gives me strong hints of being a sort of Rousseauvian 'natural' 'paradise' where 'if it feels good, do it' and 'anything goes' and there's no real logic or reason not provided by the robot overlords, but merely a 'good vibing' with everything and anything (aka Hell) - a reflection of our degenerate ethics of late modernity, the inversion of high and low culture, body and social body - as opposed to the appealing ascetic, scholarly self-control of Second Foundationers and their ethic.
I digress: in the climax, Gaia and both Foundations are brought to a three-way Mexican standoff, and Trevize (one of the main characters) is, through a bit of Deus ex magic, forced to choose between the three alternate visions for the future: the First Foundation's realpolitik, high technology, and militarism, the Second Foundation's monastic, ascetic scholarship and hidden-hand paternalism, and extending the hive mind of Gaia's 'good vibes' throughout the galaxy to form 'Galaxia'. The decision is entirely predictable as soon as the standoff commences, robbing it of drama and narrative force.
Trevize chooses Gaia and Galaxia, both concepts of which are emotionally repulsive to me, especially as contrasted with the adamantine beauty of the Second Foundation. If you are not innately repulsed by the Gaian good-vibes, uninhibited, state-of-nature 'paradise', you'll probably find the ending - and the book - much more to your liking. I'm of the hard Right with libertarian tendencies (like Hans-Hermann Hoppe, but further Right), and Gaianism seems to be the culmination of the collectivist Left's ideals - both the old Marxist Left and the post-70s postmaterial New Left's combined. I'm also very religious, but the scientific materialism of the first trilogy didn't put me off at all, so I don't think it plays a role in my rating here.
This choice of the Gaian vision for the future is why the ending is crushingly unsatisfying to me. They're not antiheroes, or evil-is-a-matter-of-perspective types: they are definitely Asimov's good guys, but I find their vision, vibing, and robot paternalism repulsive. I don't often have emotional reactions to fiction books, but boy, did I to this one's conclusion.
The two Foundations' memories of Gaia are wiped, and the First Foundation's suspicions of the survival of the Second are allayed. Both Foundations believe they've won a victory.
However, Trevize finds out that Gaia (or some other actor) is hiding the existence of Earth - the origin planet - from him, and reveals that he chose the Gaian vision because he was 'temporizing' and believed it could be reversed (though he says he doesn't think it likely he made the wrong decision), whereas the other options would immediately have given either the First or Second Foundations complete hegemony. It is only in this hope that the Gaia/Galaxia plan comes to naught that I read the next book in the series.
I hope it comes to naught to redeem the series, for as-is, it has been like listening to a Wagner opera with a hideous screech at the end of the record, which taints the enjoyment of what came before.