A useful reminder that there isn't any evidence for "multiverses," minds are nowhere near ready for "uploading," and that no biologist has ever been able to create life from non-life.
In the 1850s, Darwin's theory of evolution removed the need for a god to have designed all living things. Then a century of brilliant scientists cracked the mysteries of physics, cured feared diseases and explained inheritance through DNA. Science was on a roll and, to atheists, must have seemed to be on the verge of finishing off religious belief. By the 1950s, life, it was said, was about to be made in a test tube, artificial intelligence in computers was just around the corner, and the mind would be fully accounted for by behaviorist psychology and brain chemistry. It must have seemed that the Sea of Faith was enduring, as Matthew Arnold feared, its "melancholy, long, withdrawing roar."
Then the going got tough for the atheists. While the amount of successful science done increased enormously, the spectacular breakthroughs of the previous century dried up. That was especially so in the areas that were supposed to make the world uninhabitable for religious belief or for any non-materialist view of humanity. The process of making life from nonlife, which was believed to have happened by chance near the beginning of the earth's history, could not be replicated in the laboratory even in the most favorable conditions. Artificial intelligence has remained rudimentary; even its signature success— victory over the world chess champion in 1997—was mostly a demonstration of the uniqueness of human intelligence. The computer Deep Blue played chess by searching hundreds of millions of moves a second, assisted by rules cloned from human experts. It could not think about the game like a human. The programmers' inability to make computers imitate understanding, that most human of mental activities, exploded our naïve and simplistic views of the mind.
To make matters worse, physics unexpectedly created trouble. (Physics? Et tu, Brute?) Physics is the science of matter itself, the foundational science for all the other natural sciences. In the 1960s and 1970s, it gradually became clear that the universe was very "fine-tuned" for the existence of life. If the basic physical constants, like the strength of gravity, had been very slightly different, the universe would be unable to support life. The fine-tuning is very, very fine: for the strength of gravity, perhaps one part in 10 to the power of 40. In the physicist Freeman Dyson's words, "it almost seems as if the Universe must in some sense have known that we were coming."
For those who prefer not to have a Divine Engineer tuning the dials, the alternatives are unpalatable. The most natural are multiverse theories, according to which all possible universes exist simultaneously and we simply find ourselves in the one that makes our existence possible. This is not out of the question, but there is no actual evidence for it. It is just an "atheism of the gaps," calling imaginary entities from the vasty deep to plug a theoretical hole. The postulation probably involves gods, too—maybe not the omnipotent creator of the Abrahamic religions, but surely some unlikely combination of quantum fluctuations could produce Zeus and his colorful activities? Zeus is just a very big superman (physically, of course, not morally) up on Olympus and thus something that physics could manage to account for. The other possibility is to hope that there is some unknown mathematical reason why the constants are locked in as they are—again, a possibility, but one for which there is currently no other evidence.
The book will be quite satisfactory as a generally reliable introduction for readers who know nothing about the subject. But those who are prepared to try something more nuanced would be wise to consider three recent books by serious philosophers: "There Is a God" by the former noted atheist Antony Flew; Ronald Dworkin's "Religion Without God"; and Thomas Nagel's "Mind and Cosmos." They reach similar conclusions to Mr. Aczel's, but the authors are all top-flight (yet generally accessible) philosophers. None of their arguments make revealed religion any more likely. But the days of triumphalist scientism are over.