Facts change all the time and what is known about the world is constantly in flux. There is an order to the state of knowledge, an explanation for how facts are formed. Samuel Arbesman is an expert in the field of scientometrics, literally the science of science. In this book, Arbesman encompasses a wide variety of fields and speeds of change all illustrated with intriguing examples. The Half-Life of Facts is a riveting journey into the counterintuitive fabric of knowledge, offering a new way to measure the world and showing the limits of how much can be known with certainty.