Alone in The Universe: Why Our Planet Is Unique, by John Gribbin

At the core of this relatively short book is a pretty simple concept: there are few enough habitable zones and they are close enough to earth, that if there was any other civilization worth finding in the galaxy, we would have found them or they would have found us. The book itself explains why this is the case, and the end result is a book that is well-written but also deeply lonesome. This is the sort of book that I have read before, but it is usually relating to the Goldilocks principle of how it is that the earth “just happens” to be “just right” as a planet, showing the way that the universe appears fine tuned for life because the fundamental constants of the universe appear to be just what they need to be to encourage life. The same appears to be true when it comes to the conditions of the solar system and the place of the earth within the solar system. Yet while books on cosmological constants tend to be uplifting and encouraging because they are written from the point of view of people who believe in God and who view the fine tuning to be evidence that Someone out there cares about us in the great expanse of the heavens. This book doesn’t have that hope, and so what it leaves the reader with is a sense of the reality of the nearly unique fitness of our solar system and our part of the galaxy, but without the hope that there is something out there worth finding and exploring and celebrating.

This book is about 200 pages long, divided into eight chapters of material. The book begins with acknowledgements and a preface where the author discusses the earth as being the only intelligent planet–and probably not intelligent enough at that. This is followed by an introduction that discusses the poor odds for there being an inhabitable planet that would be another Gaia like our own. After this the author discusses two paradoxes and an equation (1): the Drake equation, the inspection paradox, and the Fermi paradox, and answers to them. This is followed by a discussion of what is so special about our place within the Milky Way, in a place which gives a lot of time in between chaotic and troublesome interactions with other parts of the galaxy (2). After this comes a discussion of the qualities that make the sun special as a star (3), including the narrow zone of life and efforts to postpone doomsday. After this the author discusses what is so special about the solar system (4), including the making of planets and the geography of the solar system. Then comes a chapter on what is special about the earth (5), which includes a discussion of the importance of plate tectonics and a comparison between earth and its neighbors Mars and Venus. After this comes two chapters that discuss what is so important about the Cambrian explosion of life, with the first of the two chapters discussing contingency and convergence (6) and the second discussing the difference between hothouse Venus and snowball earth (7). The last chapter discusses what is so special about us as beings to give us the intelligence we have and do not always use well (8), after which the book ends with further reading and an index.

The sort of isolation I read here about mankind at present being the only civilization and the only life form on earth that has ever existed that is capable of exploring and settling the stars is the same sort of isolation I read about when I see other scientists and scientifically-inclined people talk about how it is that mankind is all alone on this planet without any near kin. There are a lot of people who speak badly about the role of religion when it comes to intellectual life, but this book and others like it demonstrate that there is a real difference in books that have a perspective of hope and faith and those, like this book, which do not. The end result is not a bad book, exactly, but it is a book that feels deeply sad. This sadness is not an act, it is not put on, it is the real melancholy, even despair, of someone who looks at the universe in its wide expanse and does not want to be alone, but sees the odds to be small that we will survive long enough to settle beyond the earth before we destroy ourselves and does not see there being anyone out there to find or anyone who could find us. It is hard to ignore a sadness that deep, yet see it honestly expressed as it is here.