This is a book about the history and basic concepts of science--and above all about wonder and the “exploration” of the “cosmic perspective.” We get a guided tour through the solar system and beyond. The back of the book boasts this is “one of the best-selling science books in the English language” and we’re told its companion 13-part television series, which aired in 1980, was “the most widely watched series in the history of American public television.” In the 1984 introduction Sagan tells us that “the book and the television series evolved together;” the 13 chapters of the book correspond to the 13 episodes of the series. A book however, allowed Sagan to go “more deeply into many topics.” This isn’t simply the script to the series--it’s much more; it’s own entity. Sagan says in the 1984 introduction to the book that little of the science in the few years since had become “obsolete” despite “new findings.” Over two decades has gone past since and I’d say from what I know that’s still true--of the science. His politics, mostly hammered upon in the last chapter, struck me as not just preachy and out of place but in its moral equivalency of the old Soviet Union and the United States as dangerously naive as the Noninterventionist "America First" Movement that sought to appease Hitler. If today global warming is all the rage, Sagan’s bete noir then was the prospect of a nuclear winter. Sagan can also be “scientist-centric” in ways that sometimes annoyed me, as when he complained that our consumer culture is cluttering the radio waves which he needs to seek extraterrestrial life! In any case, the Soviets are a thing of the past, and what annoyed outweighed by what was enjoyed. And even if some of its facts are no longer true--Pluto, for instance, being demoted from a planet (and little here involving quantum mechanics)--I’d say there’s still some value in the book in sparking an interest and understanding of science. Sagan isn’t just lucid, with the ability to make an ordinary person understand difficult concepts and immense scales (although not even he, Hawking or Einstein can make Relativity explicable to me) but he can write poetic prose that inspires awe in the workings of the universe. And I do find some of his social speculations interesting--for instance the possible connection between slavery, the mind/body estrangement promoted by philosophers such as Plato and the extinguishing of the incipient scientific revolution of the Hellenistic Age. One major caveat though is that if you buy it, do so in trade paperback or hardcover form. Not only does the mass market paperback stint on the spectacular photographs included in those editions, it features eye-killing tiny font. Although truth to tell, I loved Sagan’s Dragons of Eden and The Demon-Haunted World a lot more than Cosmos. Maybe because in the end, too much of the material in Cosmos was already familiar to me. And given the intervening years dating much of the material, I'd recommend books by Hawking, Bill Bryson or Brian Greene on this theme over Cosmos.