The Genetical Book Review: The Half-Life of Facts

So, today, Thursday, September 27, is the day that the book you’ve all been waiting for finally hits bookstores! What? No, not J. K. Rowling’s The Casual Vacancy. I mean Sam Arbesman’s The Half-Life of Facts.

[Disclaimer: Sam is a friend and colleague. In particular, he has been a great supporter of the Ronin Institute. So, to be completely honest, if I had hated the book, I probably would not tell you. On the other hand, as per the general policy of the Genetical Book Review, if I had not enjoyed it, I would not have finished it, and would not have written about it at all.]

The Half-Life of Facts owes its inception to this article in the Boston Globe in which Sam introduced the concept of the “mesofact”:

When people think of knowledge, they generally think of two sorts of facts: facts that don’t change, like the height of Mount Everest or the capital of the United States, and facts that fluctuate constantly, like the temperature or the stock market close.  

But in between there is a third kind: facts that change slowly. These are facts which we tend to view as fixed, but which shift over the course of a lifetime. For example: What is Earth’s population? I remember learning 6 billion, and some of you might even have learned 5 billion. Well, it turns out it’s about 6.8 billion.

Mesofacts are the facts that disorient us. We do okay with fast-changing facts, which we expect to be different from day to day or from week to week. We also do okay with those facts that are stable enough that whatever we learned in elementary school is still true when we are picking up our grandchildren from elementary school. Mesofacts are the ones that are stable enough that we commit them to our long-term memory and then quit thinking about them. Then, years later, we are surprised when the “facts” we thought we knew turn out to be wrong.

The mesofact concept plays an important role in The Half-Life of Facts, but the book’s scope is actually much broader. It covers a host of topics related to how and why facts change. We learn, for instance, that (in contrast with the opening of the mesofacts article quoted above) the height of Mount Everest does change. Its actual height changes every year due to the uplift of the Himalayas, the melting of glaciers, etc. Also, our knowledge of its height has changed over time as measurement techniques have been improved.

We also learn about some of the science that studies how scientific knowledge changes over time. This field, called “scientometrics,”is one that the author has worked in, and the book includes first-hand accounts of a number of interesting studies.

[As an aside, doesn’t it seem like this field should have been called “scientology”? I think I’ll start referring to people who work in this area as “scientologists.” I sure hope that doesn’t cause any confusion.]

As Sam emphasizes in the book, individual changes in facts tend to be random, depending on serendipity of invention or discovery. However, if we zoom out a bit, we find that many facts change at regular rates, which can be empirically determined. You’ve probably heard of Moore’s Law, which states that computing power doubles about every two years. Sam shows that analogous laws exist for all sorts of things, ranging from Roomba technology to the number of neurons from which it is possible to record simultaneously.

There are discussions of how facts spread through human populations and how our cognitive biases can prevent us from assimilating new facts. There are accounts of cutting-edge research on creativity in cities and historical accounts of scientific innovations, like when Francis Galton “ushered in the Statistical Enlightenment” by doing things like introducing fingerprinting to Scotland Yard and constructing “a map of beauty in the British Isles, based on how many pretty women he encountered in various locations.”

One such historical account is of the time that John Wilkins (no recent relation) invented the metric system. While I, as a red-blooded American, bear no truck with the metric system, which was clearly designed as a gateway to socialism, I do celebrate the achievements of all Jo(h)ns Wilkins.

So, now you’re asking yourself, “Is this the book for me?” The writing is very informal and accessible. For the most part, technical terms are eschewed entirely. Those few that are in there are defined clearly. So, the bar for entry is quite low. If you have an interest in how the world changes — and how our understanding of the world changes — you needn’t worry that the book will be over your head.

If you have an existing interest in these sorts of things, you will probably find that you are already familiar with a number of the book’s topics. However, you will also find a lot of things you probably did not know (like that there’s a Moore’s Law of average distance of daily travel in France!), as well as interesting tidbits about things you did know (like that Gordon Moore originally proposed his law on the basis of just four data points).

Perhaps the most salient thing that you will find in terms of the style of the book is Sam’s unrelenting and infectious enthusiasm. If you’re not a scientist, he does a great job of conveying why doing science is so cool. If you are a scientist, he will help to remind you why you loved science so much before years of dealing with funding and bureaucracy broke your spirit.

Personally, the thing that I loved about the book is the way that it presents science as a living, breathing, evolving thing, defined more by a process and a mode of discovery than by the collection of stale “facts” that you had to memorize for your high-school classes. Internalizing this vision of science is a large part of what graduate school is about. You spend years unlearning all of the stuff you spent the previous years learning. You learn that the correct, “scientific” answer to yes-or-no questions is almost always “yes, but . . .” or “no, but . . .” It is problematic in my view that we continue often to present science as black and white and finished both to lay audiences and to young scientists.

Maybe if enough people read this book, that fact will change.

Buy it now!!

What’s that? You say you want to buy this book? And you want to support Lost in Transcription at the same time? Well, for you, sir and/or madam, I present these links.

Buy The Half-Life of Facts now through:


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