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Intelligent Life in the Universe
Intelligent Life in the Universe by I. S. Shklovskiĭ and Carl Sagan. Published by Emerson-Adams Press, Incorporated.
509 pages, Mass Market Paperback
First published January 1, 1966
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June 14, 2009
Shklovsky's work is comprehensive and compelling. This is where Carl Sagan got his start - writing extensive foot-notes to Shklovsky's definitive exploration of the scientific and mathematical evidence for his conclusions that first, there almost certainly IS other intelligent life in the universe, and second, we will almost certainly never find them - and this was written before the expansion of the universe had been inferred.
January 19, 2018
A masterful collaboration between two of the world's best astrophysists of the 20th century. The book begins with an exploration of the physical universe, something I found particularly useful as somewhat of a Physics rookie - Biology is my primary field. Sagan and Shklovskii then move on to talking about the primary topic of the book: Life. In particular, the possibility for the presence of life throughout the universe. The book supposes that life (in it's most rudimentary form) is in fact likely to be extremely common throughout the universe. This is acheived through the use of previous experimental data and theoretical work which is wholly convicing even as a reader 50+ years post-publication. The rigourous scientific method applied by both authors serves to make this book highly relevant in the present day, as they do not make conclusions readily upon little hard evidence. When there is evidently a dearth of understanding on a topic for, for example in the formation of our solar system, they present differing views that still stand to this day as valid discussion. This makes this book an invaluable asset to anyone wishing to learn more about the possibility of extraterrestrial life and in particular intelligent extraterrestrial life.
Being a biologist, I found the parts focusing on astrobiology to be particularly interesting. I thus enjoyed the conjectures about what extraterrerstrial beings would look like and what the conditions for life are. A particular highlight of the book is the in depth explanation of how we would go about communicating with interstellar communities which was elegantly explained by the authors.
I found the book to be enchanting and awe-inspiring from beginning to end. I was drawn to this book from Carl Sagan's book 'Pale Blue Dot', and I have to say this book has wildly surpassed my expectations. There are extensive references for further reading on the topic which also remain relevant today. This is partly due to the topic at hand being largely theoretical and containing many conjectures meaning that present day thinking has not signigicantly advanced or changed. The only significant elements missing from this book to the 21st centry reader are solely due to the book being published 50+ years ago. These are the wealth of additional insights we have about our solar system (in particular to Mars), and also the subsequent search for extraterrestrial intelligence by SETI which has yielded some extra material that warrants discussion although our search has been largely unsuccessful so far. These two facets of contemporary space science have been tackled in part by 'Pale Blue Dot' which I would also highly recommend.
The only part of the book I found to be particularly frustrating, as one naturally would, was the use of the Drake equation and von Hoerner equations to estimate the number of technical civilisations in our galaxy. I found that the estimates were wildly optimistic and this distanced me from the discussion slightly. I do appreciate that they were noted as simply estimates, although I found the conjecture to be a bit too far reaching in some respects. I would have liked a more rounded discussion on the possible presence of no life in the universe (e.g. Fermi paradox), although I admit this does not quite fit in with the narrative the book is publisizing. Nontheless, I give the book a 5 star rating for the stimulating discussion and brilliant execution of such a massive topic as Intelligent Life in the Universe.
Being a biologist, I found the parts focusing on astrobiology to be particularly interesting. I thus enjoyed the conjectures about what extraterrerstrial beings would look like and what the conditions for life are. A particular highlight of the book is the in depth explanation of how we would go about communicating with interstellar communities which was elegantly explained by the authors.
I found the book to be enchanting and awe-inspiring from beginning to end. I was drawn to this book from Carl Sagan's book 'Pale Blue Dot', and I have to say this book has wildly surpassed my expectations. There are extensive references for further reading on the topic which also remain relevant today. This is partly due to the topic at hand being largely theoretical and containing many conjectures meaning that present day thinking has not signigicantly advanced or changed. The only significant elements missing from this book to the 21st centry reader are solely due to the book being published 50+ years ago. These are the wealth of additional insights we have about our solar system (in particular to Mars), and also the subsequent search for extraterrestrial intelligence by SETI which has yielded some extra material that warrants discussion although our search has been largely unsuccessful so far. These two facets of contemporary space science have been tackled in part by 'Pale Blue Dot' which I would also highly recommend.
The only part of the book I found to be particularly frustrating, as one naturally would, was the use of the Drake equation and von Hoerner equations to estimate the number of technical civilisations in our galaxy. I found that the estimates were wildly optimistic and this distanced me from the discussion slightly. I do appreciate that they were noted as simply estimates, although I found the conjecture to be a bit too far reaching in some respects. I would have liked a more rounded discussion on the possible presence of no life in the universe (e.g. Fermi paradox), although I admit this does not quite fit in with the narrative the book is publisizing. Nontheless, I give the book a 5 star rating for the stimulating discussion and brilliant execution of such a massive topic as Intelligent Life in the Universe.
September 15, 2020
A very enjoyable and interesting exploration of almost all the relevant aspects of intelligent life in the universe, that strikes a perfect balance between popular/academic science and breadth/depth.
It is a unique product of collaboration during the Cold War, and highlights the often-overlooked pioneering contributions of Soviet scientists.
A few of the scientific points have significantly shifted since it was published, but many of the more interesting speculative elements have become the leading lines of research in their areas.
I found the considerations of the practicalities of contact with intelligent extra-terrestrial life particularly interesting. There is also interesting speculation on the validity of what came to be known as paleocontact theories; a field which now abounds with conspiracy theories as serious academics almost entirely neglect it.
Despite Shklovsky's sometimes bleak realist view (in the Russian version he explains why this materialist view is not ‘pessimistic’), there is a lot of optimism and inspiration throughout. Sadly, his call to Marxist philosophers to study the historical and speculative elements of the past, present, and future development of space-faring civilisations, (along with other inspiring calls to action in the Russian version) has been almost entirely ignored.
Sagan’s contribution to Shklovsky’s original Russian version is considerable, but sometimes not for the better.
Sagan clearly lacked a good understanding of dialectical materialism, and so did not understand the importance (or even relevance) of the Marxist method to scientific study and speculation. I imagine he saw Shklovsky’s references as a politically correct formality to appease censors, or an ideological quirk not firmly held in belief. The consequence is that Sagan removed or neglected to give proper space for these areas in the new text.
Sagan was also too optimistic in his estimates and consequent predictions. These stem from his idealistic belief in human progression towards peace, as opposed to Shklovsky's materialist outlook which correctly concludes long-term world peace to be highly improbable as long as capitalism survives on Earth (a scenario which was made more likely by the disintegration of the USSR).
(And on a purely nit-picking note, Sagan constantly swaps between standard scientific units and imperial units)
There are also some significant interesting sections of Shklovksy’s original text that are completely omitted (it’s not clear whether this was by mutual agreement or not, but the text certainly suffers for it):
1. The chapter on radio contact includes an interesting report on American discussions of different mortal threats to civilisation on earth and social/cultural tendencies towards cosmic exploration, in which Shklovksy argues for the communist transformation of society, and exposes the crisis of bourgeois ideology reflected in the non-Soviet scientific community.
2. Shklovsky's chapter on the pace and nature of technological development is entirely removed from the English version. In it he explores limits of resources and capacity, explains that many of the associated problems will be partially solved as soon as Capitalism is removed from the Earth, and calls for quick action against the worldwide crises approaching (at best, in a matter of mere centuries).
3. Shklovsky's inspiring final chapter is also completely omitted. In it he discusses the Fermi Paradox, and outlines the ethical duties that follow from our apparent loneliness: we may be, at least now and in the limited part of the universe that we may survive long enough to explore, the “vanguard of matter”, and this knowledge should “foster a sense of responsibility for the actions of individuals and all of humanity”.
There are probably more instances of note that I have not found. I would really appreciate a new translation of the original, unaltered, Russian text into English, but I imagine I’m more or less alone (I guess I’ll have to make do with a PDF of the Russian text put through Google translate).
“It seems to us that the conclusion about our loneliness in the Universe (if not absolute, then practically) has great moral and ethical significance for humanity. The value of our technological and especially humanistic achievements grows immeasurably. The knowledge that we are, as it were, the ‘vanguard’ of matter, if not in the whole, then in a huge part of the Universe, should be a powerful stimulus for the creative activity of each individual and all of humanity. The responsibility of mankind grows enormously in connection with the exclusivity of the tasks facing it. The inadmissibility of atavistic social institutions, senseless and barbaric wars, suicidal destruction of the environment becomes extremely clear.” — Iosif Shklovsky, Universe, Life, Intelligence (1962)
It is a unique product of collaboration during the Cold War, and highlights the often-overlooked pioneering contributions of Soviet scientists.
A few of the scientific points have significantly shifted since it was published, but many of the more interesting speculative elements have become the leading lines of research in their areas.
I found the considerations of the practicalities of contact with intelligent extra-terrestrial life particularly interesting. There is also interesting speculation on the validity of what came to be known as paleocontact theories; a field which now abounds with conspiracy theories as serious academics almost entirely neglect it.
Despite Shklovsky's sometimes bleak realist view (in the Russian version he explains why this materialist view is not ‘pessimistic’), there is a lot of optimism and inspiration throughout. Sadly, his call to Marxist philosophers to study the historical and speculative elements of the past, present, and future development of space-faring civilisations, (along with other inspiring calls to action in the Russian version) has been almost entirely ignored.
Sagan’s contribution to Shklovsky’s original Russian version is considerable, but sometimes not for the better.
Sagan clearly lacked a good understanding of dialectical materialism, and so did not understand the importance (or even relevance) of the Marxist method to scientific study and speculation. I imagine he saw Shklovsky’s references as a politically correct formality to appease censors, or an ideological quirk not firmly held in belief. The consequence is that Sagan removed or neglected to give proper space for these areas in the new text.
Sagan was also too optimistic in his estimates and consequent predictions. These stem from his idealistic belief in human progression towards peace, as opposed to Shklovsky's materialist outlook which correctly concludes long-term world peace to be highly improbable as long as capitalism survives on Earth (a scenario which was made more likely by the disintegration of the USSR).
(And on a purely nit-picking note, Sagan constantly swaps between standard scientific units and imperial units)
There are also some significant interesting sections of Shklovksy’s original text that are completely omitted (it’s not clear whether this was by mutual agreement or not, but the text certainly suffers for it):
1. The chapter on radio contact includes an interesting report on American discussions of different mortal threats to civilisation on earth and social/cultural tendencies towards cosmic exploration, in which Shklovksy argues for the communist transformation of society, and exposes the crisis of bourgeois ideology reflected in the non-Soviet scientific community.
2. Shklovsky's chapter on the pace and nature of technological development is entirely removed from the English version. In it he explores limits of resources and capacity, explains that many of the associated problems will be partially solved as soon as Capitalism is removed from the Earth, and calls for quick action against the worldwide crises approaching (at best, in a matter of mere centuries).
3. Shklovsky's inspiring final chapter is also completely omitted. In it he discusses the Fermi Paradox, and outlines the ethical duties that follow from our apparent loneliness: we may be, at least now and in the limited part of the universe that we may survive long enough to explore, the “vanguard of matter”, and this knowledge should “foster a sense of responsibility for the actions of individuals and all of humanity”.
There are probably more instances of note that I have not found. I would really appreciate a new translation of the original, unaltered, Russian text into English, but I imagine I’m more or less alone (I guess I’ll have to make do with a PDF of the Russian text put through Google translate).
“It seems to us that the conclusion about our loneliness in the Universe (if not absolute, then practically) has great moral and ethical significance for humanity. The value of our technological and especially humanistic achievements grows immeasurably. The knowledge that we are, as it were, the ‘vanguard’ of matter, if not in the whole, then in a huge part of the Universe, should be a powerful stimulus for the creative activity of each individual and all of humanity. The responsibility of mankind grows enormously in connection with the exclusivity of the tasks facing it. The inadmissibility of atavistic social institutions, senseless and barbaric wars, suicidal destruction of the environment becomes extremely clear.” — Iosif Shklovsky, Universe, Life, Intelligence (1962)
September 7, 2013
Read it in the late 70s, in the original hardcover edition from 1966 (apparently not even listed here at Goodreads), as background while preparing a review of Carl Sagan's 1979 popular-science book, Broca's Brain. This collaboration with Soviet astrophysicist Iosif Shklovsky, which was a revised, extended, and retitled version of a book Shklovsky had published in 1962, struck me when I read it—and still does—as scientifically much more serious and focused than what I was reviewing. And yet I can see now a similarity: informed speculation. Among other subjects, Broca's Brain presented some of what Sagan had managed to glean from a field not his own, neuroscience, and from there ventured upon some guesses. (Though it had its virtues, the book also advanced a romanticized view of the nature of scientific work.) Likewise, Intelligent Life in the Universe first broadly surveyed much of what was known about biology, astrophysics, et al., before considering some possibilities for further thought and research. As its title reveals, smart aliens were among the possibilities. In science, which is never complete, somebody somewhere must always speculate.
Some parts of the book's survey of astrophysics remain with me still: a chart known as a Hertzsprung-Russell diagram, for instance, and the most common path of development for a star, called the main sequence. Mostly lost in the mists are its thoughts about life elsewhere in the universe. My middling rating therefore is based mainly on not remembering the book in much detail.
Some reviewers here have called the book dated. In science, work done yesterday may be dated today. What matters is whether it was in any way fruitful or useful. Wikipedia's entry on Shklovsky assesses Intelligent Life in the Universe as "the first comprehensive discussion of this field" without attributing it (which such entries aren't supposed to do). My guess is that the book occupies a particular place—though I can't say exactly what it is—in the history of what we now call exobiology. In a recent glance through the endnotes of an upcoming book on the subject, Five Billion Years of Solitude: The Search for Life Among the Stars, I noticed a reference to this work, so I'm not the only one to see it as old but not forgotten.
Some parts of the book's survey of astrophysics remain with me still: a chart known as a Hertzsprung-Russell diagram, for instance, and the most common path of development for a star, called the main sequence. Mostly lost in the mists are its thoughts about life elsewhere in the universe. My middling rating therefore is based mainly on not remembering the book in much detail.
Some reviewers here have called the book dated. In science, work done yesterday may be dated today. What matters is whether it was in any way fruitful or useful. Wikipedia's entry on Shklovsky assesses Intelligent Life in the Universe as "the first comprehensive discussion of this field" without attributing it (which such entries aren't supposed to do). My guess is that the book occupies a particular place—though I can't say exactly what it is—in the history of what we now call exobiology. In a recent glance through the endnotes of an upcoming book on the subject, Five Billion Years of Solitude: The Search for Life Among the Stars, I noticed a reference to this work, so I'm not the only one to see it as old but not forgotten.
November 5, 2021
Lo primero que debemos saber de este libro, es que se publicó en 1966, antes de los viajes Apolo cuando la humanidad aún no habia pisado la superficie lunar, pese a eso este libro nos habla de exoplanetas, de la posibilidad de vida en otros planetas y otros sistemas solares.
Pero muy desactualizado claro esta, nos habla de las misiones Mariner, la construcción de Arecibo ya demolido y de la ecuación de Drake como surgió tras una conferencia de 1961 con detalles que nunca habia leido.
No recomiendo este libro por su antiguedad, yo me propuse leer todos los librosde Carl Sagan y este es uno de los que me faltaban.
Pero muy desactualizado claro esta, nos habla de las misiones Mariner, la construcción de Arecibo ya demolido y de la ecuación de Drake como surgió tras una conferencia de 1961 con detalles que nunca habia leido.
No recomiendo este libro por su antiguedad, yo me propuse leer todos los librosde Carl Sagan y este es uno de los que me faltaban.
October 28, 2019
One of the most rewarding reading experiences of my life. It's more dense and science-y than Cosmos, but it is perfect for someone looking for something a little deeper in terms of why things are the way they are.
The book spans the creation of the universe, to the formation of galaxies, the life cycle of the stars, the formation of heavy elements, the origins of planets, and the birth of our own solar system - not just the rough idea, but the actual science.
Then the authors explore life: what it is, what it can be, where and how it may arise spontaneously, and they speculate on the abundance and nature of possible life elsewhere. Finally, we learn how we may detect, and possibly communicate with that life.
A great book. That it was written in the 60's is astounding. We were only just starting to scratch the underbelly of space with mankind's first satellites, and yet we already knew so much by way of genius insight and beautiful experimentation. The things that were unknown (or unknowable) to the authors, but are common knowledgs shows how far cosmology and biology have come in the last 55 years or so.
Shklovskii is the original author, asoviet space scientist. This translation to English, and the collaboration and additions by Carl Sagan during that process during the height if the Cold War is a triumph of the human mind and spirit. This book shows how serious and imaginative a scientist Sagan was.
I will remember these feelings of awe for the rest of my life. It is dense, but it is worth it.
The book spans the creation of the universe, to the formation of galaxies, the life cycle of the stars, the formation of heavy elements, the origins of planets, and the birth of our own solar system - not just the rough idea, but the actual science.
Then the authors explore life: what it is, what it can be, where and how it may arise spontaneously, and they speculate on the abundance and nature of possible life elsewhere. Finally, we learn how we may detect, and possibly communicate with that life.
A great book. That it was written in the 60's is astounding. We were only just starting to scratch the underbelly of space with mankind's first satellites, and yet we already knew so much by way of genius insight and beautiful experimentation. The things that were unknown (or unknowable) to the authors, but are common knowledgs shows how far cosmology and biology have come in the last 55 years or so.
Shklovskii is the original author, asoviet space scientist. This translation to English, and the collaboration and additions by Carl Sagan during that process during the height if the Cold War is a triumph of the human mind and spirit. This book shows how serious and imaginative a scientist Sagan was.
I will remember these feelings of awe for the rest of my life. It is dense, but it is worth it.
September 5, 2023
El libro, a pesar de su título, da un exagerado repaso de astronomía que resulta desalentador. Por supuesto, es necesario hacer una pequeña introducción para ubicar al lector, en especial a aquel que no está familiarizado con la astronomía básica. En este libro, sin embargo, esta introducción resulta excesivamente larga y pesada. Aquellos lectores que ya tengan conocimientos de astronomía les parecerá innecesaria y aquellos que no los tengan les resultará demasiado técnica (Shklovskii es especialmente pesado, con cálculos matemáticos incluidos, mientras que Sagan es más dicharachero).
El libro se escribió originalmente por Shklovskii en 1961, siendo traducido al inglés y ampliado por Sagan en 1966. La traducción al castellano ya llegó en 1985. El lector encontrará, por tanto, abundante información obsoleta (en 1966 se logró el primer aterrizaje no tripulado en la Luna, el primer sobrevuelo de otro planeta se había logrado en 1965, no es de extrañar que los capítulos dedicados a los planetas produzcan cierto sonrojo). Hay errores comprensibles y otros no tan justificables y, en numerosas ocasiones, aciertos notables.
Me gustó especialmente la introducción, dedicada a las teorías de la antigüedad sobre la multiplicidad de mundos y los últimos apartados, dedicados a lo que me esperaba al iniciar el libro. La parte de evolución estelar, formación planetaria, etc sigue siendo vigente hoy en día. Todo lo referente a los planetas de nuestro sistema solar está anticuadísimo y no merece la pena más allá de la curiosidad histórica.
El libro se escribió originalmente por Shklovskii en 1961, siendo traducido al inglés y ampliado por Sagan en 1966. La traducción al castellano ya llegó en 1985. El lector encontrará, por tanto, abundante información obsoleta (en 1966 se logró el primer aterrizaje no tripulado en la Luna, el primer sobrevuelo de otro planeta se había logrado en 1965, no es de extrañar que los capítulos dedicados a los planetas produzcan cierto sonrojo). Hay errores comprensibles y otros no tan justificables y, en numerosas ocasiones, aciertos notables.
Me gustó especialmente la introducción, dedicada a las teorías de la antigüedad sobre la multiplicidad de mundos y los últimos apartados, dedicados a lo que me esperaba al iniciar el libro. La parte de evolución estelar, formación planetaria, etc sigue siendo vigente hoy en día. Todo lo referente a los planetas de nuestro sistema solar está anticuadísimo y no merece la pena más allá de la curiosidad histórica.
April 23, 2021
Pensar en la posibilidad de descubrir vida más allá de la tierra es un sueño que al menos yo espero cumplir en mi vida. Este libro relata esta utopia más allá de la imaginación y aterriza nuestra creatividad a todas las escalas de la magnitud de la posibilidad de vida. Un libro con una complejidad técnica importante que requiere de atención y releer para captar la esencia de las muchas temáticas que se debe tener en cuenta para la vida extraterrestre y no se diga de la vida inteligente y técnica en el universo. Un viaje que nos lleva a los confines del cosmos y al final nos aterriza en la tierra para darnos la posibilidad de ser quienes creemos nuestros compañeros en este viaje estelar. Inteligencia natural o artificial en algún punto se funcionarán y la distinción perderá valor.
March 6, 2025
Read it way back when I was still in my teens and in college, during early 70s. It was a dazzling , inspiring read…kind of a detailed primer form astronomy for me …learnt so much about the universe and the various theories bout what kind of life that can be around .
I still remember the plates , beautifully illustrated . This was from the library at IIT Kharagpur..1973 or so.
And it was a hard bound original, with two authors, Schklovwki of the then USSR and with Sagan as the co author
I still remember the plates , beautifully illustrated . This was from the library at IIT Kharagpur..1973 or so.
And it was a hard bound original, with two authors, Schklovwki of the then USSR and with Sagan as the co author
September 19, 2023
Interesting book, despite the fact that Sagan tried his best to destroy the UFO hypothesis that the Soviet authors have developed in the fifties and sixties. With the influence of Agrest and Felix Zigel.
December 8, 2017
This book was a good friend for a long time.
August 11, 2025
plurality, triangulation, zoo, magnetohydrodynamics, eating, jovial, stellar, abandonment, isotropically, probabilistic
March 22, 2022
A fascinating precursor to Cosmos, Pale Blue Dot and The Voyager missions (with all the uncertainties of the state of astronomy in 1966 ingrained in the text)...does not skimp on the math.
September 25, 2012
The first part of this book is a popular introduction to astronomy and cosmology; as far as I can tell, it is accurate but dated: a lot of discoveries were made after this book came out: pulsars, gamma-ray bursts; cosmic microwave background radiation was discovered just before the book was published. Also, a lot of what we know about the Solar system was found by robot explorers such as the Voyagers, which then just began to fly. The book speculates that dinosaurs became extinct at the end of the Cretaceous period because a nearby supernova explosion bathed Earth in mutagenic radiation; nowadays it is thought that it was an asteroid impact. The second part briefly defines life and speculates on its origin; for a more modern and interesting treatment, see Life's Solution by Simon Conway Morris, though take it with a grain of salt because the author is a creationist. It then speculates on life in the Solar system with a particular emphasis on Mars, life on Earth as seen by hypothetical Martian astronomers, and life in other solar systems. It discusses vision in alien animals without mentioning echolocation, a perfectly good substitute used by Earth bats and whales. The third part discusses radio and laser contact with extraterrestrial civilizations, and speculates on whether the satellites of Mars are of artificial origin; we now know that they aren't: the reason they have such low density is that they are piles of cosmic rubbish.
If you are interested in this kind of stuff, please read something newer such as Life as We Do Not Know It by Peter Ward.
If you are interested in this kind of stuff, please read something newer such as Life as We Do Not Know It by Peter Ward.
July 11, 2013
Well written, highly readable, but far too dated to be useful or even terribly interesting. It must have been fascinating in the late 60s, but I was left wondering how much of what they said has turned out in the long run to be even close to true. Some of the description of methodology has been interesting, though.
Read
August 1, 2009read this a long time ago. i remember being shocked that i was reading it first of all then even more shocked that i thoroughly enjoyed it and laughed a lot. carl is funny. yes, his a funny scientist.
Want to read
February 25, 2008recommended by mr.sinopoli
Currently reading
April 14, 2008The best book on the subject. It covers a lot of ground in fine style.
February 17, 2010
Fun for a stubborn 8th grade geek.
August 2, 2010
A little dense for the casual reader. But a really wonderful resource nonetheless.
October 3, 2012
I thought this book was important, and interesting to me.
January 6, 2013
Delighted and dazzled me when I read this in high school (late 60's). Out of date now.
April 13, 2017
Interesting read, more interesting was too see how long certain ideas and theories have been around, and which ideas are still being churned over by modern day physicists and scientists.
Displaying 1 - 23 of 23 reviews