The Demon-Haunted World by Carl Sagan

I just finished reading a book that I should have read fifteen years ago, when I first saw it in the library: Carl Sagan’s The Demon-Haunted World: Science as a Candle in the Dark.

Over the past couple of years, I’ve taken to listening to the Skeptic’s Guide to the Universe podcast, thanks to a recommendation from Bryan on a post I wrote about podcasts back on the first incarnation of my bloggery, NOVA Geoblog. It seems like every month or two, this book by Sagan gets raised by the rogues as one of the best resources for introducing neophytes to skeptical thinking. I figured it was about time that I read it myself.

It’s good. I’ve read several of Sagan’s books previously, including Contact and The Dragons of Eden, so I knew he was a talented writer. The topic of Demon-Haunted World is rational thinking, the value of science as a way of sorting truth from non-truth, and democracy by a well-informed skeptical populace as being the only way to run a robust society.

Sagan begins with a topic near and dear to his heart (and his previously-established readership): aliens. He examines the phenomenon of UFO sightings around the world, with diversions into alien abduction, crop circles, and the perception of a government conspiracy which seeks to secretly promote human-extraterrestrial hybrids. He chalks it all up a mass fantasy, a shared delusion among a significant portion of our populace, and then goes back to another period in history when there was a similar society-wide perception of demons everywhere, constantly flitting through the shadows and performing a very similar role (incubi and succubi were similarly sexually-focused characters as modern “probing” aliens). By delving deeply into these two topics, one of contemporary concern and one of pre-modern concern, their parallels are explicit. The discussion shows us that no matter how “advanced” we think we are, we are susceptible to falling for bad ideas.

Sagan then discusses the pernicious societal habit of burning women as witches — a sad practice which clearly was the product of a mass delusion which has since passed. His point is that we are indeed capable of believing very silly ideas, and then acting on them even when the consequences are as harmful as can be imagined.

We are fallible beings, Sagan says. The way to counter being led into horrible acts by false ideas is to apply reason, logic, and experiment. He focuses most of his attention on the low-hanging fruits of modern skepticism: woo, monsters, UFOs, conspiracy theorists, but doesn’t ignore other delusions that have similarly weak foundations. (The Spanish Inquisition gets a mention.) He’s respectful of the idea of religion, but cuts into specific claims which fall within the testable envelope of scientific inquiry. Sagan shows science to be an evolutionary process, evaluating new claims on a continuing basis, and always ready to toss ideas which might have worked last week but are shown to be false this week. In this effort, Sagan earns major points from me by enumerating a list of his own past mistakes, including his apparently much-ballyhooed and much-derided claims about the global environmental impacts of the first Gulf war’s burning oil wells.

This is a point that I think is an essential one to make — science isn’t about authority, it’s about evidence and reason. An example I like to celebrate is Charles Darwin’s ideas on the parallel roads of Glen Roy, Scotland. Darwin interpreted them as glacial striations, while they have since been shown to be strand lines etches by waves lapping at an ancient lake’s shore. Scientists were ready and willing to discard Darwin’s interpretations when a better interpretation was demonstrated. Scientists have not been willing to discard another of Darwin’s ideas, the explanation of evolution as occurring via natural selection, as no better idea has yet displaced it. It’s not because science worships Darwin as “he who could do no wrong,” but as “the one who figured it out first.”

The subtitle, “Science as a candle in the dark,” refers to this sorting of reality from imaginings. When we are alone in a dark room, our imaginations can spin all sorts of fanciful perceptions. I know that as a kid, I certainly imagined monsters hiding in my room. My brother and I love to tell the story of how one morning when I was ten and he was six, we woke to see a monster standing on the table in our room, a perfectly lucid shared hallucination, with me heroically standing up and attacking it, only to discover that it was a new toy: a plastic suit of armor. A candle would have been useful in such a circumstance. At least the plastic breastplate and helmet “monster” wasn’t a person. Then my mis-perception could have led to a tragic and unwarranted attack. Sagan’s point is that science is a tool that prevents us from making false attacks on those who are not truly threatening us.

Another time, as an adult camping in the Mojave desert, my friend Kenny and I took a night hike and spotted a glowing form ahead of us in the dark. What was it? We got spooked: an alien? With a bit of (what seemed to us to be) daring gusto, we moved forward, and the glowing thing got larger. Then the path angled a bit to the right, and the glowing diminished. We got closer, and realized that we had been getting ourselves worked up over… a puddle of water. Sitting in an opferkessel atop an outcrop of impermeable quartz monzonite, the puddle had merely been reflecting the starlight above. My own mind had turned this innocuous puddle into a luminous being: an E.T. or a patronus. I’m a pretty skeptical guy, so these sorts of experiences really mean a lot to me, demonstrating how my own brain can push me into perceiving non-real entities. Only the rigor of science, Sagan says, allows us to distinguish these imagined ideas from reality. Just because our own consciousness perceives it, that doesn’t make it real.

The last couple of chapters of the Demon-Haunted World take a turn towards the political. Sagan attempts to make the connection between science (as a way of separating true from false) and democracy (separating societal right from wrong). To me, this connection seemed a little strained. Though it sounds as if Sagan and I have pretty much identical political views, this connection that science begets democracy seems a bit of a non sequitur to me. His point is that both systems have good self-correcting mechanisms as part of their regular function. Both systems allow each person (each scientist or each citizen) to use their own critical faculties to make their own decisions, and thus both systems only reach their full potential when everyone who participates is thoughtful and deliberate.

Sagan was a bright, thoughtful person. It’s a shame he’s not still around with us, to celebrate the wonder of life on Earth (I’d love to hear his take on last week’s arsenic-substituting bacterium from Mono Lake), or to take frauds, hucksters, and FOX News to task. Fortunately, I reckon he’s shown the rest of us how we can do those jobs in his absence. The ballooning spread of the skeptic “movement,” facilitated by the Internet, seems to be a very real legacy of Sagan’s efforts.

Bottom line: Demon-Haunted World was an important read in 1996 (the year it was published). In many ways, it packs less of a punch to a reader in the present day (2010), but that’s probably because some people have been heeding its lessons. I’m glad I took the time to read it, and I recommend you do, too.