Book Review: Demon-Haunted World

This is the first of what will be only an occasional contribution, since I have planned these for a while but appear to be slow in completing them. More, however, are on the way…

The Demon-Haunted World: Science as a Candle in the Dark is probably the most well-known of Carl Sagan’s books, and is almost considered a handbook of skepticism and critical-thinking. It’s hard to say whether this was intentional or not – Sagan was always a huge promoter of critical thinking, but by its own admission it is a science book. From my standpoint, however, it should be recommended reading for anyone with a teen reading level onward, regardless of one’s views towards science, or even their misgivings about it. In only one place does the science that Sagan enthuses over actually involve something like equations, and he’s patient enough to explain them without forcing the reader to comprehend the values – this is about James Clerk Maxwell’s sudden discovery, through what was really a mathematical experiment, of the nature of electromagnetism and its relation to light and radio waves. “Relation” being rather the wrong word here, since at that point they were found to be the same thing, a discovery that has enormous impact on everything we do today.

More compelling, however, is Sagan’s examination of our everyday world. He builds his cases carefully, keeping the reader captivated with concise writing as he gently steers to his target by eliminating the other choices. Sagan, especially in this book, is a humble yet enthusiastic writer, who asks more questions than he answers, yet asks the right ones, never telling the reader what must be the case yet allowing them to eliminate the other options. In this regard, he mimics one aspect of the scientific method, in that he tries to determine if any other conclusion might fit as well, if not better, which would throw the initial conclusion into doubt. In this way, science tests itself and weeds out alternative explanations.

To me, the most distinctive parts of the book are where he examines the witch hunts of Europe before the Enlightenment, chronicled through writers of that time. If, like me, you knew only of Salem during that period, these chapters will be shocking – Salem was a drop in the bucket in a time of senseless and inescapable persecution, based on a corrupt belief system and meaningless assertions. We’d like to think we know better now, but Sagan manages not to couch it in terms of past ignorance, but compares it with present assertions, demonstrating that we are not immune to such behavior unless we make the efforts to ask the hard questions and demand support for claims. Indeed, he makes direct comparisons to alien abduction accounts and the questionable methods of investigating such.

Sagan goes into great detail regarding the famous abduction case of Betty & Barney Hill, relating facts that most accounts somehow miss. These facts, far from being extraneous, have direct bearing on the reliability of the testimonies, and provide an eye-opening experience into the world of UFO investigation. It becomes evident that some conclusions are reached not through weight of the evidence, but by other means – wish fulfillment, perhaps, or pre-existing biases. And while many people find no surprise at this, Sagan takes pains throughout the book to demonstrate that such behavior does not belong to “fringe” beliefs alone.

Another fascinating read are the samples of public opinion, snippets of responses he had received in the mail following the publication of chapter excerpts in Parade magazine. If the reader is still dubious about the need for thinking skills in this modern age, this cross-section of American opinion certainly helps drive the point home. The responses from a high school classroom are particularly disturbing. It’s one thing to hear, or even believe oneself, that much of the public is ill-informed, but seeing the examples of it always has a greater impact.

It is here that he introduces what has become known as the “Baloney Detection Kit,” a list of practices and common fallacies that serve admirably to sort out the accuracy of any claim, and that form the basis of all critical thinking. It is difficult to imagine a situation where such practices would not serve a useful purpose – but there are plenty where they were, and are, desperately needed. Sagan includes a simple story in a footnote, one that demonstrates the fallacy of, as he calls it, “observational selection” – counting the hits that confirm your hypothesis, and ignoring the misses:

[From pg 214] My favorite example is this story, told about the Italian physicist Enrico Fermi, newly arrived on American shores, enlisted in the Manhattan nuclear weapons Project, and brought face-to-face in the midst of World War II with U.S. flag officers.

So-and-so is a great general, he was told.
What is the definition of a great general? Fermi characteristically asked.
I guess it’s a general who’s won many consecutive battles.
How many?
After some back and forth, they settled on five.
What fraction of American generals are great?
After some more back and forth, they settled on a few percent.

But imagine, Fermi rejoined, that there is no such thing as a great general, that all armies are equally matched, and that winning a battle is purely a matter of chance. Then the chance of winning one battle is one out of two, or 1/2; two battles 1/4, three 1/8, four 1/16, and five consecutive battles 1/32 – which is about 3 percent. You would expect a few percent of American generals to win five consecutive battles – purely by chance. Now, has any of them won ten consecutive battles …?

Another striking thing about this book is the sheer number of places you can stop reading and contemplate an introduced idea. I have myself taken advantage of this with a blog post, and will likely do so again soon. Sagan is succinct, able to explain his point with clarity and without additional verbiage or redundancy, and thus covers a vast array of topics and ideas – so many that it’s impossible to do justice with a brief book review. I was struck with the thought that this could serve almost as a textbook, with work assignments or essays based on aspects of each chapter – and what a remarkable class that would be. If you are a “thinker,” this book is a buffet.

Through it all, he does indeed promote science – not as the idea of learning valences and calculating vectors, but as the practice that serves virtually all of our advances as a species. He realizes that science has a bad reputation in the US, and indeed much of the world, and suggests ways to counteract this. His own writing, the delight in discovery and the fascination with how things work and where this leads, shows that he knows it can be done, and that we all have to eliminate this idea of science as “hard.”

Towards the end of the book, he apologizes for devoting a couple of chapters to politics, but even here Sagan cannot become polarized. The reader dreading the polemic of political parties today will find themselves cringing for nothing – Sagan instead details the careful considerations and knowledgeable backgrounds of our founding fathers, most notably Thomas Jefferson, and the efforts they put into crafting the documents that govern this country. The fact that this bears no resemblance whatsoever to our current political figures is damning all by itself, with no input given or necessary by Sagan.

Carl Sagan had a couple of gifts: one of reasoned debate without rancor; and the other of boundless fascination with the natural world. Both are exemplified in this book, without ever leaving his message behind. My challenge to anyone is to simply read a chapter – any chapter. If you’re not convinced, I’ll turn in my book reviewing badge. And if your child is tackling reading at the level of Mark Twain or Edgar Allan Poe, they’re ready for this book.