When I picked up The Grand Design by Stephen Hawking I was expecting a fairly in-depth look at some specifics about M-theory and how it might be a possible candidate for a 'theory of everything' in physics. I figured that the supposed theological and philosophical implications of this would be tangents which the media had blown out of proportion. I was mistaken. The Grand Design is appropriately--though ironically-- titled and has a very broad scope focusing on 'the big questions', the history of science and the current most complete scientific understandings as they supposedly relate to those questions. All done with a minimal amount of mathematical detail, easily understandable language, and a large number of illustrations and metaphors.
It made for a quick and enjoyable read. As an overview of the history of science it's a wonderful little guide. And I was startled that the entire purpose of the project seemed to be to address the 'big questions'--most prominently the question posed by Leibniz "why does something exist rather than nothing?"-- by tracing the historical responses to those questions, both 'religious' and more modern scientific 'answers', culminating with M-theory. I was startled because serious physicists, including Hawking, tend to shy away from addressing such questions in their work, preferring to let the work and its implications speak for themselves--if indeed there are any implications for 'the big questions'. This made the project much more interesting for me as it makes it of more direct relevance to issues that I'm interested in. Unfortunately the book doesn't really address the philosophical and metaphysical issues that it purports to address at all.
In the second paragraph of the book Hawking proclaims that "philosophy is dead" and that it has been replaced by science. It seems he neglected to have one philosopher--or at least logician--proofread his work, as directly on the heels of that pronouncement he launches into a defense of the philosophical proposition that scientific determinism is true. A philosopher would have been able to inform him that all of his methods and conclusions rest on various philosophical presuppositions. So from the very outset he begins to undermine himself by failing to properly set up the terms of the conversation.
At least twice in the book he contrasts a scientific understanding of the world that has been proven to be true against a specifically Young-Earth creationist proposition that has been proven to be false in a seemingly self-satisfied way, never bothering to differentiate between Young and Old Earth creationism. Revealing himself to be fairly uninformed as to the various positions that are held on the issues at hand. However when it comes to the metaphysical arguments of natural theology--such as the Kalam cosmological argument and the teleological argument--he does seem to have some grasp of the significance of those arguments and addresses them head on, for the most part. In my estimation his lack of comprehension of the relevant philosophical terms--such as 'nothing' and 'being'--prevents him from making a sound rebuttal to those arguments, though he does seem to grasp how the arguments work. Indeed, one entire chapter reads almost like something out of Reasons to Believe's catalog where he extensively lists all of the fine-tuned parameters of the universe. He believes the fine-tuning is essentially due to chance--if quantum fluctuations result in 10^500 universes, one of them will have the fortunate properties of this one and it will appear to be designed and appear to be fine-tuned for life. Despite his alternate explanation of the fine-tuning of the universe, this account of how the universe is fine-tuned is very well laid out and can actually be a useful source to cite. The universe is magnificently, precisely fine-tuned for human life: Stephen Hawking says so himself.
The book concludes abruptly and strangely stating that "Because gravity exists the universe can and will create itself from nothing." Which, even if that statement is true, doesn't even address Leibniz's question of "why is there something rather than nothing?" All it does is describes how one physical state--subatomic empty dimensional space governed by the laws of quantum mechanics--transfers into another state. Or how something goes from being something to being something else. Secularists who are more rigorous logistically and philosophically correctly attempt to dismiss the question as either meaningless or nonsensical. This is actually the proper approach. Either the question can't be answered or the answer is supernatural. Hawking's whole project then, as exciting as it may appear to him, is doomed from the start. And precisely for philosophical reasons, philosophy which he deemed to be irrelevant and useless.
Physics, as an investigation of mechanisms internal to the universe--or if not the universe the 'multiple histories of the universe' as Hawking would have it--is impotent to address the question of the source of being. Fine-tuning without a fine-tuner? The Grand Design without a Grand Designer? If these notions seem incoherent on their face, that's because they are. And though Hawking attempts to explain why such nonsensical notions might actually in fact be the case, he doesn't present any compelling evidence why we should believe that they are. Indeed, M-theory has not been experimentally confirmed, and it's difficult to see how it ever could be. Not to mention that even if it ever was empirically confirmed it would still fail to address the 'big questions' that this book claims to address.