With something in the jaw-dropping neighborhood of 480 books to his credit by the time of his death in 1992, it is surprising to realize that science fiction made up comparatively little of Isaac Asimov's ouevre. (Most of his books were nonfiction works on virtually every scientific discipline known to man.) It is just that the good doctor's contributions to this genre were so revolutionary and influential that even if he had not produced a single word of SF after, say, the 70's, his place at the top of the pyramid would be assured. And perhaps no work of science fiction is more important, famous, historic, or insert-your-own-hyperbole-here than the original novels of the Foundation Trilogy (which eventually went on to span seven books). There is perhaps no living SF writer who was not in some way influenced by these tales, and I'll bet you dollars to donuts that the ones who say they aren't are lying.
Foundation is one of those books that has become such a historical tentpole of the genre that it is easy to dismiss and take for granted, much in the same way young moviegoers today might find it hard to figure out all the fuss about Citizen Kane. But Foundation is not a book that's "great" simply because critics tell you it is. It really is a tremendously written and entertaining piece of sociopolitical SF combined with good old space opera, and its best attributes might seem quaint to today's readers until you realize just how beautifully they're executed. Asimov's blessedly clear prose, for example. When you consider over the decades how much SF has become overburdened by either vain style or cumbersome plotting masquerading as epic legendry, Asimov's concise words are a true breath of fresh air. Asimov knew perhaps better than anyone in this genre that writing was about communicating. Asimov wrote clearly, but not laconically. There is more than enough wit to go around. Most impressively, Asimov's plots were as intricate as any of today's best novelists'. Yet he still managed to keep his readers' heads free from confusion and frustration.
Set at least 13,000 years in the future, after humanity has colonized space so thoroughly that most people have forgotten about the Earth itself, Foundation opens as the Galactic Empire is in its final years, having reigned over the galaxy for over 10 millennia. One man on the capital planet of Trantor (a world which, incidentally, George Lucas unabashedly swiped and renamed Coruscant for use in Star Wars Episode I: The Phantom Menace) dares to stand up and tell the moribund Empire that its decline and fall is inevitable. Hari Seldon has developed the science of psychohistory, which aims to predict the behavior of large populations over vast periods of time. Seldon has predicted not only the fall of the Empire, but the fact that a whopping 30,000 years of barbarism will follow, unless his organization, the Encyclopedia Foundation, is able to finish its immense task of cataloging and preserving millennia of accumulated human knowledge and history. Then, perhaps, the 30,000 years can be shaved to a mere millenium.
Banished by the Empire to a remote world at the edge of the galaxy (a move actually foreseen by Seldon's psychohistory), the Foundation begins its work...but not only to assemble the Encyclopedia as announced. Seldon's real intent has been to set the wheels in motion so that, if his predictions of future trends indeed prove correct, this little world (and another just like it at the far end of the galaxy which Seldon has already set up) will be the true foundation of an all-new and more benevolent Second Empire.
The novel then covers about 200 years, during which Seldon's psychohistoric predictions prove accurate and the outer rims of the galaxy begin breaking away from the Empire and forging a number of little independent kingdoms. Asimov expertly details the way in which the Foundation manages to maintain not only its independence in this tumultuous environment, but manipulates itself into a position of dominance by casting itself as a center of, of all things, religious faith. Later on, as the Foundation's lone possession of the secrets of nuclear power helps keep it at the top of the political food chain, a merchant economy develops, and along with it a talent for waging economic warfare that none can defend against.
The various chapters of this novel were in fact first published as short fiction in Astounding (the precursor to Analog), but Asimov melded them together into novel form seamlessly. Through three compelling characters — Seldon; the Foundation's mayor Salvor Hardin; the merchant prince Hober Mallow — the story of the Foundation's rise is told with surprisingly little overt action, but loads of incredibly entertaining political savvy. Readers who love "corridors of power" storytelling, with all of its machinations and suspense, will have a ball here.
But Foundation's enduring fame and influence aren't just rooted in its plot. This novel is essentially the story that saw the first major culmination of a process that had been slowly developing for years: the maturation of SF as a literary genre, away from the pulpy days of green monsters and that "crazy Flash Gordon stuff" towards Campbell's ideal of a literature of ideas and reason. You don't get a whole lot (well, any) of exploding spaceships in this book. What you do get are characterizations and sociopolitics that continue to ring true 50 years later, all couched in a cracking good tale that whizzes along as if it were Star Wars. But in Foundation, Asimov helped set a real foundation indeed: the idea that good SF must engage the whole mind.