Book Review: The Half-Life of Facts: Why Everything We Know Has an Expiration Date

According to the book itself, “This book is a guide to the startling notion that our knowledge—even what each of us has in our head—changes in understandable and systematic ways.” Written by Samuel Arbesman, The Half-Life of Facts: Why Everything We Know Has an Expiration Date is about enabling the reader with an understanding of how facts change, because if we have an understanding of how they change, we can better cope with the world around us.

Arbesman took on quite the task by writing this book. Thinking about how facts change is interesting, but once you get into the very comprehensive details about how they change, the different kinds of facts, and everything in between, it begins to be a little difficult. I won’t lie—this is a hefty 200-page book about facts. However, I am glad that I read it.

There are a lot of thought-provoking ideas discussed in this book. When he was in medical school, the author’s father noticed that the answer choices remained the same for a test two years in a row, but the correct answer itself changed. A quantitative theory for the advancement of scientific advances was discovered by Derek J. de Solla Price when he stacked a complete set of Philosophical Transactions of the Royal Society of London up against a wall and noticed that the heights of the volumes increased exponentially from year to year.

Arbesman has a very pleasing writing style as well. It’s very informative, but rather quirky and playful in some areas. Here are a few of my favorite quotes:

  • “Facts change all the time. Smoking has gone from doctor recommended to deadly. Meat used to be good for you, then bad to eat, then good again; now it’s a matter of opinion. The age at which women are told to get mammograms has increased. We used to think Earth was the center of the universe, and our planet has since been demoted. I have no idea any longer whether red wine is good for me.”
  • “If you look back in history you can get the impression that scientific discoveries used to be easy. Galileo rolled objects down slopes; Robert Hooke played with a spring to learn about elasticity; Isaac Newton poked around his own eye with a darning needle to understand color perception. It took creativity and knowledge (and perhaps a lack of squeamishness or regard for one’s own well-being) to ask the right questions, but the experiments themselves could be very simple. Today, if you want to make a discovery in physics, it helps to be part of a ten-thousand-member team that runs a multibillion-dollar atom smasher.”
  • “The phrase actuarial escape velocity was popularized by Aubrey de Grey, a magnificently bearded scientist obsessed with immortality.”

This book is not exactly a simple read, but it is pleasantly challenging and intriguing, and Arbesman’s lively writing style eases the reading experience. The book also helps the reader develop a new framework for thinking about the world. If we can develop a better understanding of how facts work, we can work better with the “informational treadmill” that we live in. Arbesman provides us with a method for this in The Half-Life of Facts: Why Everything We Know Has an Expiration Date. As he wrote, “This book is a guide to the science behind the vibrations in the facts around us.”