Oxford University Press
2013 | 227pp | £25
Reviewed by Colin John Humphreys
Imagine we woke up tomorrow to news that there is intelligent life elsewhere in the universe. What would be the implications? And just how likely is it that such life might exist outside of our Earth? As I read this brilliant book, which presents the arguments for and against very readably, I found myself oscillating between believing that humans are unique in the universe and feeling that there must be many other planets containing intelligent life.
On the one hand, there is Enrico Fermi’s paradox
: at lunch one day in 1950, the famous physicist asked aloud, ‘Where is everybody?’, referring to alien visitors. Fermi argued that if the Earth is not special in having intelligent life, then civilisations should already have evolved many times in our galaxy, since there are billions of stars older than the Sun. If any one of these civilisations had wanted to colonise the galaxy, they could have done so by now. Since there is no compelling evidence that any aliens have visited the Earth, we must conclude that we are alone.
On the other hand, one of the pioneers of the search for extraterrestrial intelligence, Frank Drake
, estimated that there were probably between 1000 and 100 million advanced civilisations in our galaxy. But the problem with such estimates is that one is multiplying the very large number of planets in our galaxy with the very small probability of the conditions on a particular planet being ‘just right’ for intelligent life to emerge.
The author of this excellent book has PhDs in both astrophysics and systematic theology and he provides a detailed discussion of the issues involved: physical, biological and theological. As Arnold Wolfendale, a previous Astronomer Royal, says in the book’s foreword: ‘For atheists and believers alike, there is much food for thought.’ This book would be ideal for anyone interested in the possibility of intelligent life elsewhere else in the universe. I will be buying it for someone myself.