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Probability 1: Why There Must Be Intelligent Life in the Universe
The best-selling author of Fermat's Last Theorem integrates probability theory with the latest scientific findings from the Hubble telescope and the Mars missions to argue for the existence of intelligent life beyond Earth. 50,000 first printing. $50,000 ad/promo. Tour.
230 pages, Hardcover
First published January 1, 1998
12 people are currently reading
332 people want to read
About the author
Amir D. Aczel
46 books152 followersAmir Aczel was an Israeli-born American author of popular science and mathematics books. He was a lecturer in mathematics and history of mathematics.
He studied at the University of California, Berkeley. Getting graduating with a BA in mathematics in 1975, received a Master of Science in 1976 and several years later accomplished his Ph.D. in Statistics from the University of Oregon. He died in Nîmes, France in 2015.
He studied at the University of California, Berkeley. Getting graduating with a BA in mathematics in 1975, received a Master of Science in 1976 and several years later accomplished his Ph.D. in Statistics from the University of Oregon. He died in Nîmes, France in 2015.
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Displaying 1 - 14 of 14 reviews
September 29, 2015
This is a pleasant, even charming book about the possibility of extraterrestrial life written by a mathematician who failed to read the popular literature on the subject. He thought that the general public was in doubt about the probability of extraterrestrial life, and he wanted to make one modest point, namely that because the universe is so incredibly vast, it is almost a cinch that life exists elsewhere. The problem with this is, just about anybody with an interest in extraterrestrial life knows that. Aczel thought he was bringing us a bulletin, carefully framed and double checked, and proven. What he should have known is that not only is his news is not news, but as Hamlet said to Rosencrantz and Guildenstern, "Your news is not true."
Aczel is the author of Fermat's Last Theorem, a book that enjoyed a popular success that perhaps gave him the encouragement he needed to think that he should write a book announcing to the world that he had proven, mathematically, that life does indeed exist on other worlds. Alas and alack, he really didn't prove anything. Most people are more convinced by common sense, given the billions of stars in our galaxy and the billions of other galaxies, that life must exist elsewhere, than they would ever be by such a mathematical "proof" as is contained herein. Fact is, one of the numbers Aczel plugs into his proof is not known, and is merely an assumption on his part. He declares without a shred of evidence "that the probability of life occurring on any single planet that is already within its star's habitable zone is extremely extremely remote: one in a trillion" (p. 212). Sorry, but that is not good enough. As someone else has pointed out on this site, the number could just as easily be one in a trillion, trillion, trillion. How about 1 in a googolplex of googolplexes? Size DOES matter.
Notice the full title of this book: "Why There Must Be Intelligent Life in the Universe." Aczel's entire argument includes the idea that life inevitably leads to intelligent life. In Chapter Seven, "The Evolution of Intelligence," he quotes studies showing that the brain size of animals in general is growing, that the dinosaurs had on average larger brains at the time of their demise than they did earlier, and that mammals have gradually developed larger brains.
This proves nothing of course, being (for one thing) a planetary sampling of one. Actually it proves that Aczel did not read the literature because he would have known that there is a very real controversy about whether intelligent life follows as a matter of course from life itself, or whether intelligent life is a very rare development. (See, for example, Dared Diamond's argument in Extraterrestrials: Where Are They? (1995), edited by Ben Zuckerman and Michael H. Hart.)
In the final analysis the failure of this book is not in the writing and nor in the presentation nor in the conclusion. It's in the arrogance. Just because one is an expert in statistics, it doesn't follow that one can apply one's knowledge to an entirely different field and get positive results. Furthermore, as stated above, if you are going to write a popular book, bringing the benefit of your knowledge to a popular audience, you really ought to read the literature. That way you may know as much about the subject as your prospective readership.
--Dennis Littrell, author of “The World Is Not as We Think It Is”
Aczel is the author of Fermat's Last Theorem, a book that enjoyed a popular success that perhaps gave him the encouragement he needed to think that he should write a book announcing to the world that he had proven, mathematically, that life does indeed exist on other worlds. Alas and alack, he really didn't prove anything. Most people are more convinced by common sense, given the billions of stars in our galaxy and the billions of other galaxies, that life must exist elsewhere, than they would ever be by such a mathematical "proof" as is contained herein. Fact is, one of the numbers Aczel plugs into his proof is not known, and is merely an assumption on his part. He declares without a shred of evidence "that the probability of life occurring on any single planet that is already within its star's habitable zone is extremely extremely remote: one in a trillion" (p. 212). Sorry, but that is not good enough. As someone else has pointed out on this site, the number could just as easily be one in a trillion, trillion, trillion. How about 1 in a googolplex of googolplexes? Size DOES matter.
Notice the full title of this book: "Why There Must Be Intelligent Life in the Universe." Aczel's entire argument includes the idea that life inevitably leads to intelligent life. In Chapter Seven, "The Evolution of Intelligence," he quotes studies showing that the brain size of animals in general is growing, that the dinosaurs had on average larger brains at the time of their demise than they did earlier, and that mammals have gradually developed larger brains.
This proves nothing of course, being (for one thing) a planetary sampling of one. Actually it proves that Aczel did not read the literature because he would have known that there is a very real controversy about whether intelligent life follows as a matter of course from life itself, or whether intelligent life is a very rare development. (See, for example, Dared Diamond's argument in Extraterrestrials: Where Are They? (1995), edited by Ben Zuckerman and Michael H. Hart.)
In the final analysis the failure of this book is not in the writing and nor in the presentation nor in the conclusion. It's in the arrogance. Just because one is an expert in statistics, it doesn't follow that one can apply one's knowledge to an entirely different field and get positive results. Furthermore, as stated above, if you are going to write a popular book, bringing the benefit of your knowledge to a popular audience, you really ought to read the literature. That way you may know as much about the subject as your prospective readership.
--Dennis Littrell, author of “The World Is Not as We Think It Is”
September 7, 2010
The title of the book pretty much says it all. The author builds up to his conclusion that there must be intelligent life in the universe by covering chemical, physical, and astronomical facts, and then doing a basic probability calculation. I found it pretty dry reading until the last few chapters, though I think I did learn some things I didn't know before.
However, it worries me that someone with Aczel's background would misstate something so obvious as the relationship between the seasons & the hemispheres. "When Earth's northern hemisphere is facing the Sun during daytime, it is summer, and when the southern hemisphere faces it, it is winter." (p. 125). Well, no ... that statement is true only in the northern hemisphere; in the southern hemisphere, the opposite is true. A careless statement like that makes me wonder what other things he's misstated that I don't know enough to catch.
However, it worries me that someone with Aczel's background would misstate something so obvious as the relationship between the seasons & the hemispheres. "When Earth's northern hemisphere is facing the Sun during daytime, it is summer, and when the southern hemisphere faces it, it is winter." (p. 125). Well, no ... that statement is true only in the northern hemisphere; in the southern hemisphere, the opposite is true. A careless statement like that makes me wonder what other things he's misstated that I don't know enough to catch.
September 10, 2023
Worth a read if into mathematics, specifically probability, maybe worth a look if into UFOs, astronomy, biology. Spoiler: he ultimately concludes there’s a hundred percent chance there’s intelligent life out there, in an infinite or at least massive universe. Spends most of the time though providing context into chemistry, physics, probability, and astronomy. Good idea, but the last two chapters seemed rushed and thrown in at the end. I never grasped his explanation why the probability in some scenarios he brought up were 49 or around 50%, counter to common thought. He brushed over this part too fast in my opinion. Found it lucid in much of the earlier chapters, so that’s a plus. But overall his aim could have been much better in a 1 or 2 page essay. Never touches the topic that aliens could already be visiting us despite all the public and military testimony, video evidence, etc.
November 9, 2021
Fascinating and scientifically accurate read.
If you're interested in the possibility of life in the universe, based on an accurate scientific approach, then this book is a must read.
If you're interested in the possibility of life in the universe, based on an accurate scientific approach, then this book is a must read.
November 4, 2012
Originally published on my blog here in March 2001.
The question of the existence of extra-terrestrial life is one which has fascinated the human race since classical times. In recent years, various attempts have been made to estimate the likelihood that such life exists, prompted in some part by the popularity of science fiction. This sort of speculation begins with what is known as the Fermi paradox, which is basically that we should already know if there is intelligent life more advanced than we are because they should have contacted us already.
This way of looking at things actually suggests other questions, which are rather more interesting that whether life exists at all; it would be hard to get excited by a universe populated only by micro-organisms other than on our own planet. Basically, these other questions amount to speculation about what form putative extraterrestrial life might take - could there be advanced civilizations? How could we know? They actually lead back to close study of life on earth, to try to see how things could have developed differently.
There is an equation, the Drake equation, which predicts the likelihood of contact by an advanced alien race; this is put together by assigning probabilities and expected values to various events, most of which is guess work - the probable lifetime of a civilization, for example. Aczel's book, after a discussion of some of the issues raised in the previous paragraph, makes an estimate for the first few values in the equation, those which refer to the existence of life itself rather than levels of technology, and infers from this that the probability of life existing somewhere else in the universe is essentially indistinguishable from 1, certainty.
This is done through some elementary probability theory, which essentially amounts to saying that the universe is so big that, no matter how unlikely, life must exist somewhere. This is saved for the end, but much more interesting is Aczel's explanation of why he thinks humanity might well be the most mature civilization in the universe (as a result of the inspection paradox, unfortunately not as clearly explained as most of the mathematics in the book).
The book as a whole is not as successful as Aczel's earlier explanation of Fermat's Last Theorem, at least as far as I am concerned. A lot of it is over-simplified - I ended up skipping a lot of the early part of the book. It picks up in the middle, when nuggets of interesting information start to be included, but unfortunately becomes less interesting again as it starts to concentrate on the existence of life in general rather than intelligent life.
The question of the existence of extra-terrestrial life is one which has fascinated the human race since classical times. In recent years, various attempts have been made to estimate the likelihood that such life exists, prompted in some part by the popularity of science fiction. This sort of speculation begins with what is known as the Fermi paradox, which is basically that we should already know if there is intelligent life more advanced than we are because they should have contacted us already.
This way of looking at things actually suggests other questions, which are rather more interesting that whether life exists at all; it would be hard to get excited by a universe populated only by micro-organisms other than on our own planet. Basically, these other questions amount to speculation about what form putative extraterrestrial life might take - could there be advanced civilizations? How could we know? They actually lead back to close study of life on earth, to try to see how things could have developed differently.
There is an equation, the Drake equation, which predicts the likelihood of contact by an advanced alien race; this is put together by assigning probabilities and expected values to various events, most of which is guess work - the probable lifetime of a civilization, for example. Aczel's book, after a discussion of some of the issues raised in the previous paragraph, makes an estimate for the first few values in the equation, those which refer to the existence of life itself rather than levels of technology, and infers from this that the probability of life existing somewhere else in the universe is essentially indistinguishable from 1, certainty.
This is done through some elementary probability theory, which essentially amounts to saying that the universe is so big that, no matter how unlikely, life must exist somewhere. This is saved for the end, but much more interesting is Aczel's explanation of why he thinks humanity might well be the most mature civilization in the universe (as a result of the inspection paradox, unfortunately not as clearly explained as most of the mathematics in the book).
The book as a whole is not as successful as Aczel's earlier explanation of Fermat's Last Theorem, at least as far as I am concerned. A lot of it is over-simplified - I ended up skipping a lot of the early part of the book. It picks up in the middle, when nuggets of interesting information start to be included, but unfortunately becomes less interesting again as it starts to concentrate on the existence of life in general rather than intelligent life.
October 30, 2008
I really enjoyed this remarkable book. I recommend it to those whose "unhealthy " obsession is extraterestrial intelligence! The writer believes that there is life on at least one extrasolar planet in the universe, which is fascinating! I think the number of intelligent civilizations in the whole universe should be in the order of thousands or even millions, considering the vastness of the universe and the number of galaxies and stars in the universe, although my idea is not based on scientific evidence but rests on reasoning and intuition. I cannot make myself believe that this vast universe has been created to house only we human beings. We are next to nothing when we consider the size of the universe and we cannot consider ourselves so precious that God created this universe only for us to live at a remote corner in the universe and at the edge of the Milky Way! I think we are only one of the thousands or millions of species in the universe, who are capable of establishing a civilization and someday - which may lie thousands or millions of years ahead - these species or civilizations will contact and will cooperate to master the universe! Is it too optimistic to be believable? I do not think so!
June 5, 2014
Interesting and readable, but a bit too light at points. The premise of this is calculating the probability of intelligent life elsewhere in the universe, but that wasn't really what happened. The vast majority of the book is an exploration of astronomy and biology and various theories about the development and necessary conditions for life. It was interesting, but at points parts appeared irrelevant and other parts didn't have enough depth. Neither part is Aczel's field of study, and I think it showed. I even picked up on a couple of mistakes made. The remainder is a quick look at probability theory, which whilst far more confidently written, was nothing I haven't seen before in school and university. Finally, at the end, Aczel calculates the probability of life (not intelligent life, as promised) existing elsewhere, very quickly arriving at a few numbers without much justification and then writing down their result. The whole thing was interesting, but unfortunately fell a fair way short of what was promised.
December 15, 2022
This began as a compulsive read, but started to drag towards the end. While I agree with the final conclusion, there seemed to me to be too many unforced errors and too much dubious reasoning. A passage about the Inspection Paradox is interesting and counter-intuitive. On the other hand, the author draws an inference of systematically-increasing encephalisation during evolutionary time which contains an anthropic bias of its own: As a species able to ask the question by virtue of an evolutionarily brief explosion in brain size, and as a life-form partaking in an evolutionary dance starting at zero encephalisation, the illusion of inevitable brain-growth comes as given. Yet for almost all of the history of life it has remained static.
Azcel concludes that the probability of life in the Universe is so close to 1 as to be indistinguishable from certainty. I agree. But some of the reasoning could have been better grounded.
Azcel concludes that the probability of life in the Universe is so close to 1 as to be indistinguishable from certainty. I agree. But some of the reasoning could have been better grounded.
January 17, 2011
Kosmologi, Biologi, Fysik, Astronomi, och inte minst en stor portion matematik och sannolikhetslära. Aczel utnyttjar flera fält inom naturvetenskapen för att sätta värden på variablerna i Drakes Ekvation. Drakes Ekvation används för att beräkna sannolikheten för liv i universum (förutom jorden), baserat på ett antal faktorer som tillväxten av nya stjärnor och andelen av dessa med planeter. Aczel kommer, inte helt överaskande, fram till att sannolikheten för att det finns liv i universum är ett.
En vidare analys ger dock förklaringen till varför vi inte redan blivit kontaktade. Sannolikheten för att det just nu existerar en annan intelligent civilisation är svårare att beräkna, men sannolikt nära noll. Liv är inte samma sak som intelligent liv.
Boken är mer metodisk än överaskande, men ändå fängslande i sitt rena användande av vetenskaplig metodik.
En vidare analys ger dock förklaringen till varför vi inte redan blivit kontaktade. Sannolikheten för att det just nu existerar en annan intelligent civilisation är svårare att beräkna, men sannolikt nära noll. Liv är inte samma sak som intelligent liv.
Boken är mer metodisk än överaskande, men ändå fängslande i sitt rena användande av vetenskaplig metodik.
April 19, 2008
I actually only read 30 pages and stopped, having found three embarrassing errors. Omitting "million" from a description of 1,420 megahertz as "1,420 cycles per second" can simply be chalked up to oversight. Referring to Andromeda as the closest galaxy to our own, and claiming that many astronomers regard Pluto to be nothing but an asteroid, utterly discredit Aczel. Most grade school children would know better. Shame on him, and on those who gave the book positive reviews.
September 18, 2011
I enjoyed this book somewhat. The first third of the book was very enteresting, dealing with mostly astronomy. The second third had more chemistry and DNA discussions. I found that a little too much. The last part of course were the authors conclusions and the final probability. Overall, the book was interesting even though I lost it during the DNA discussions.
August 8, 2018
Scialbo. Meglio leggere Civiltà Extraterrestri di Asimov. Asimov è un grande divulgatore ed ogni pagina di "Civiltà Extraterrestri" è ricca di contenuti.
March 2, 2009
A shade dry ... but otherwise elegant, well-researched and convincing.
May 2, 2017
A few years ago, I made a rule for myself: once I started a book, I would finish it. I had a habit of getting bored with books and never finishing them. This rule helped me with that problem, and I'd actually end up getting through books I didn't like more quickly than the ones I enjoyed.
Thanks to Probability 1, I'm breaking that rule.
The book isn't poorly-written. I found it mostly engaging, having filled up a few pages of notes while reading. The problem is that it has some fairly severe inaccuracies; enough so that I didn't want to take the chance of picking up any "facts" that were false.
The first instance that got me paying closer attention was when the author referred to interstellar dust clouds as "dark matter". Dark matter, for as much as we currently understand it, isn't ordinary matter. Dust is. I gave it a pass because the book was written a few years ago, so maybe that was the common understanding of dark matter at the time (though I doubt it was).
Other minor inaccuracies exposed themselves as I kept reading, including a moment where the author arrogantly assumed he put more thought into a scenario than the famous astronomer Frank Drake did. The final straw was when the author referred to Triton as being a moon of Saturn, rather than an orbiter of Neptune. If the author can misplace a moon, what else has he gotten painfully wrong? I was afraid to find out, and actually more afraid that I'd absorb something and not find out.
Now, if you're just interested in the topic and aren't as pedantic as I probably sound, you'll probably enjoy this book and learn a lot from it. If you're as careful with facts in your research as I tend to be (in the way that this author isn't), I'd steer clear.
Thanks to Probability 1, I'm breaking that rule.
The book isn't poorly-written. I found it mostly engaging, having filled up a few pages of notes while reading. The problem is that it has some fairly severe inaccuracies; enough so that I didn't want to take the chance of picking up any "facts" that were false.
The first instance that got me paying closer attention was when the author referred to interstellar dust clouds as "dark matter". Dark matter, for as much as we currently understand it, isn't ordinary matter. Dust is. I gave it a pass because the book was written a few years ago, so maybe that was the common understanding of dark matter at the time (though I doubt it was).
Other minor inaccuracies exposed themselves as I kept reading, including a moment where the author arrogantly assumed he put more thought into a scenario than the famous astronomer Frank Drake did. The final straw was when the author referred to Triton as being a moon of Saturn, rather than an orbiter of Neptune. If the author can misplace a moon, what else has he gotten painfully wrong? I was afraid to find out, and actually more afraid that I'd absorb something and not find out.
Now, if you're just interested in the topic and aren't as pedantic as I probably sound, you'll probably enjoy this book and learn a lot from it. If you're as careful with facts in your research as I tend to be (in the way that this author isn't), I'd steer clear.
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