A review of Impossibility: The Limits of Science and the Science of Limits by John D. Barrow

Written by Johanna Salu

In our academic and professional lives as young scientists, we are encouraged to memorise facts and to focus on details and intricacies, so much so that our everyday lives bear little resemblance to those of the great scientific thinkers of the past, such as Ramon y Cajal or Hermann von Helmholz. Science has changed drastically since their days, becoming more compartmentalised, and making it impossible to keep oneself apprised of the progress in every field. Thus, with only a narrow field of view, we find ourselves ill-equipped to tackle the big questions in science. Or other times, we simply forget. But every once in a while, I enjoy taking a step back from what I am doing to see how it fits into the greater scientific enterprise and to ponder about the philosophical aspects of knowledge. Impossibility by John D. Barrow offers exactly this insight.

The book provides a thought-provoking review of ideas about what is possible in the universe, whether it all can be eventually uncovered by science, and what pitfalls we might need to overcome in the quest for scientific progress. It is an excellent collection of various writers’ thoughts on science, knowledge and progress, woven into an accessible narrative by Barrow. The author mainly assumes the role of a relatively unbiased storyteller, recounting what others have contributed to the conversation on one topic or another throughout recent history. His own work is only mentioned in a few paragraphs, and he mostly refrains from offering his own conclusions and opinions, leaving it up to the reader to draw their own.

The essence of the book focuses on the question: “Will scientific progress continue infinitely?” and on the various impossibilities that hamper this progress. Perhaps scientific and technological progress, originally driven by a desire for comfort and convenience, will eventually bring about its own demise by eliminating the motivation for further research by successfully meeting our needs. Or perhaps, as time goes by, testable questions will dry up and scientific frontiers will be limited to speculation. Alternatively, progress may be hindered by prohibitive costs of developing technologies that would allow us to understand the infinitesimally small and the colossally large scales of the universe and to conduct experiments to determine which theory of nature’s laws is ultimately correct.

While some of the ideas presented in Impossibility currently remain in the domain of speculation, I found that several chapters addressed issues that more-or-less directly impact the future of neuroscience, and my role in it. One problem, for example, is that it takes a long time for one to reach the frontier of any scientific field. We already spend around twenty years in education, depending slightly on the country and the field, to reach the stage at which we begin to make original scientific contributions. As knowledge continues to accumulate, it will take increasingly longer to reach the frontier. Our options then are to increase training time or to increase specialisation. Neither comes without drawbacks. It is unreasonable to expect one to spend the bulk of one’s life preparing for a career breakthrough which, due to the uncertainty of science, is not even guaranteed to come. And eventually, even an entire lifetime just might not be enough. At the same time, it is unwise to keep narrowing the field of specialisation, as interdisciplinary work in the past has led to great progress.

We combat this problem with collaboration. A single lab now contains people with different specialisations and strengths. But in the long term, it is the large-scale international collaborations that might allow us to overcome some of the limitations of individual minds. Prominent examples of this Big Science include the Human Genome Project, the International Space Station, or the Large Hadron Collider at CERN. The dawn of Big Neuroscience is already upon us. In spite of the flaws of current Big Neuroscience attempts, it is interesting to consider that this may someday become the only viable approach for scientific progress. Reading Impossibility, I found it saddening to see the future of the romantic image of a solitary scientific genius fade into improbability. On the other hand, it was helpful to think about what traits will define the scientist of the future, and to be mindful of cultivating those traits in myself.

Barrow discusses these issues, and many more, with great care to scientific accuracy and thorough referencing. He does assume some basic working knowledge about prominent physics concepts, for example quantum theory and the many worlds interpretation (think Schrödinger’s cat), or the Big Bang theory. If you are not familiar with these concepts, you will probably need to pull up a quick Wikipedia introduction to fully understand the relevant passages. However, if you are generally interested in science and have already read a popular science book that touches on these topics, you might instead be relieved that Barrow keeps the introduction brief.

Impossibility is not the kind of book that one just cannot put down. It is a fairly dense read and requires some reader participation (intellectual engagement only) to fully deliver. I have put it down several times, only to pick it up again the next time that I am on holiday or travelling. Luckily, the end of each chapter is equipped with a short summary to refresh your memory and allow you to carry on reading where you last stopped.

If you, like me, want an introduction to broad ideas in physics, mathematics and philosophy to supplement how you think about science and its role in the world, then I think you would thoroughly enjoy this book. If you are looking for an in-depth treatment of any single topic, however, you would probably not be satisfied. For my level of prior knowledge, Impossibility has given me numerous new insights and enlightening perspectives on how to think about the impossible. I have realised that some commonly held ideas that feel intuitively reasonable are completely impossible on a closer look, yet other alien-sounding fantasies may be closer to reality than we think. Which ones? Well, you’ll just have to read the book.