Reading this book feels like working out in one of the finest philosophical and intellectual gyms in town. In it Jim Holt takes us on a journey which tackles one of the oldest and most profound questions that humans have asked; "Why is there something instead of nothing?". To his credit Holt does not try to answer the question but instead leads us through a set of meetings with some of today's leading philosophers and scientists who all have their own fascinating takes on the problem. Holt starts the book with accounts of different schools of philosophy which have tried to stake out paths from something to nothing. It turns out that it's far from easy to define the existence of "nothing" partly since the very entity defining that nothing is something. Interestingly a few of the philosophical attempts also fly in the face of the latest insights from theoretical physics, and in fact one of the goals of the book is to demonstrate the creative tension between science and philosophy, hinting that both disciplines will continue to learn much from each other. To explain nothingness, philosophers resort to various logical proofs of God and existence while physicists think that the universe could have been a random quantum fluctuation that fed upon itself. Listing various attempts to explain nothing and something, Holt dwells on the work of thinkers like Heidegger, Wittgenstein, Schopenhauer and Leibniz, giving us a sampling of philosophical speculations on the question over the last five hundred years or so.
The heart of the book however involves Holt's conversations with some very smart thinkers even as he criss-crosses the globe and spends his time in French cafes contemplating the quirks and facts of his own existence, sometimes poignantly so as he thinks about the demise of his dog and then even more sadly of his mother (practical instances of the transformation of something into nothing?). Holt's accounts of these encounters are in equal parts clear, moving and enormously intellectually stimulating, making us confront a wide variety of questions about meaning and existence. Some of the conversations feel like intellectual ping-pong, and Holt's great strength is his ability to ask these people tough questions and spar with them on an equal level; this turns the interviews into exchanges of real substance rather than simple Q&A sessions. Among the cast of fascinating characters that Holt talks to are celebrated scientists, philosophers and writers. For instance there is the Oxford philosopher Richard Swinburne who thinks that the simplest explanation for the presence of such a complicated universe is that it must be created by God. Then there's the Oxford physicist David Deutsch who is convinced of the existence of multiple universes, a fact which then posits our universe as simply one of many other worlds, albeit one containing sentient humans. An even more bizarre idea comes from the physicist Andre Linde who is sympathetic to the existence of our universe as a simulation created by other sentient beings with awesome powers of matter and energy creation. A healthy antidote to those who seem astonished by the complexities of our cosmos comes from the Pittsburgh philosopher Adolf Grünbaum who thinks there's no reason to be awed by the presence of something and that a fondness for considering nothing to be the "natural" state of the universe is really rooted in Judeo-Christian philosophy which imparts special significance to creation. Many of these thinkers hold diverse and even opposite views of the topic, but it's clearly this variety that makes pondering the question such an intellectual treat.
There are many others who Holt talks to, including the Platonist mathematician Roger Penrose, the writer John Updike and the Nobel Prize-winning physicist Steven Weinberg. From a scientific viewpoint the cleverest idea seems to come from the physicist Alex Vilenkin who defines nothingness as the result of a sphere of spacetime shrinking to zero radius; presumably the universe could then arise out of this nothingness as a quantum fluctuation. As noted above, Holt's meetings with all these thinkers are interspersed with poignant personal ruminations about life, death and existence, mostly done while lounging around in the French cafe that Sartre frequented. Interludes between conversations cover a smattering of related topics, including various logical proofs for God's existence and Holt's own criticisms of them; in Holt we find a penetrating thinker who is entirely capable of asking the most revealing questions about the topic. In addition many of the discussions are spiced with humor. Ultimately Holt does not find the final answer to the question "why is there something rather than nothing", but I don't think he is disappointed. Neither are we. This is one of those cases where the journey is far more important than the destination; like the traveler in C. P. Cavafy's poem "Ithaca", it's the sights and sounds that we see on the way which really count. The investigation exemplifies the kinds of deep questions that humans are capable of addressing through science, philosophy, literature and poetry. We should all be glad that there are people who think about these questions in such deep and diverse ways, and we can thank Jim Holt for being a patient, witty, insightful and poignant guide on this wonderful journey.