The quotes in this essay were excerpted from Carl Sagan’s The Demon-Haunted World: Science as a Candle in the Dark.

It is not the function of our government to keep the citizen from falling into error; it is the function of the citizen to keep the government from falling into error. 

—US Supreme Court Justice Robert Jackson, 1950.

I HAVE ALWAYS BELIEVED that every child, by the time they are 13 years old or so, should have three specific and non-negotiable skills. They should be able to read well; they should have a decent understanding of their individual, inalienable rights, especially freedom of speech and the sanctity of a free press; and they should understand the scientific method and how it works.

Why these three things? Because they are the foundational elements of a community-centric, free society. The ability to read represents more than access to great literature, to worlds of fancy and fantasy and horror and drama; it offers more than the ability to travel through time and space, more than the opportunity to meet a host of unforgettable characters. All good things, those. But reading also lies at the heart of critical thinking and healthy skepticism and the ability to develop a cogent and convincing argument. It is a catalyst of confidence, and an essential element of inspired leadership. It is an enabler of diplomacy and reason and governance. And reading is an essential tool for individual relevance, growth, and an assured future.

Freedoms of speech and a free, non-aligned press are, more than anything else, the most powerful protectors of true democracy that we have. They are stronger than armies, more powerful than bloviated oratory, and if protected and allowed to do their jobs, they are the single greatest threat to autocracy and demagoguery. 

And the scientific method? I don’t mean ‘something done in sort of a scientific way;’ I mean THE scientific method, the rigorous six-step process which has been around since the early 1700s and which has guided every legitimate scientific undertaking since. 

Like the other two, it’s essential. Here’s how it works. 

First, I make an observation or ask a curiosity-driven question. For example, how do bats manage to catch insects on a pitch-black night and not fly into obstacles? 

Second, I research the topic as exhaustively as I can, and that includes personally observing whatever phenomenon it is I want to research. If there is an answer in the literature, and it has already been proven correct, then I don’t have to continue any further—I have my answer. But if I don’t, I gather as much information as I can to help me design a process to come up with an answer.

Based on my research, I develop a hypothesis. “I believe that bats must have organs in their eyes that allow them to see perfectly in the dark, like night vision goggles.”

In step four, my task is to design an experiment to test my hypothesis. I capture a dozen bats (I need a dozen or more to ensure that I don’t base my research on a single bat that by chance has some kind of genetic mutation that allows it to see in the dark). In the lab, I carefully blindfold the bats and release them into an obstacle (and insect)-filled laboratory that is completely dark.

Next, I analyze the data. “After 25 identical experiments in which I released the blindfolded bats into the obstacle-filled dark space, each time radically rearranging the obstacles to ensure unpredictability and to avoid the possibility that the bats manage to memorize the layout of the obstacles in the darkened laboratory, the data reveals two facts: (1) not once did a bat ever collide with an obstacle, and (2) all the bats were well-fed and the insect population was significantly depleted during each experimental test period.”

In the final step, I report my conclusions. “Based on the data that I was able to reproducibly generate with my experimental setup, I conclude that eyesight, regardless of wavelength sensitivity, has nothing to do with Myotis lucifugus’ ability to to capture prey while avoiding randomly-placed obstacles, because the blindfolded bats behaved identically to those without blindfolds.”

Notice that all I did in this process was to eliminate one hypothesis—I didn’t answer the question. I know how they DON’T avoid obstacles and catch dinner (by seeing them), but I still have no idea how they DO avoid obstacles and catch dinner. And that brings us full-circle, back to the beginning. Another question: I have concluded that little brown bats do not rely on vision to catch prey and avoid obstacles in the dark. How, then, DO they catch prey and avoid obstacles in the dark?

Back to my research, this time with a focus that perhaps eliminates vision-oriented outcomes. A different question, perhaps: are there other senses that bats might use to avoid obstacles and locate prey besides sight? Smell might work for insect prey, but it won’t work with big foam rubber obstacles. Touch can probably be discounted, because by the time the fast-moving bat is close enough to feel the obstacle or their prey, it’s too late. What about hearing? Back to step three. “I hypothesize that bats rely on some form of sound to locate their prey and avoid obstacles in a controlled dark environment.” I design a second experiment: I take my 12 bats and fill their ears with soundproof foam to eliminate their ability to hear. I also dust each bat with harmless chalk dust, each bat a different color. I then repeat the experiment. When the experiment period ends, I turn on the lights, and lo and behold, the surfaces of the white foam blocks that served as obstacles are covered with chalky impact locations, and the insect population has not been diminished at all. 

Next, just to be sure, I create what’s called a control group. I remove the ear plugs from six of the 12 bats and clean the chalk dust from their bodies. I then dust the bats that still have ear plugs with red chalk dust, and the bats without ear plugs with yellow chalk dust. I then clean and rearrange the obstacles, and repeat the experiment. This time, when I turn on the lights, I find that the foam barriers are covered with red blotches. I conclude that hearing, not vision, is key to the little brown bat’s ability to navigate and capture prey.  But what I still don’t know is, what sound? The barriers make no sound, yet they somehow avoid them. And the insects may or may not make sound, but even if they did, would that be enough information to answer the question? The answer, of course, is no.

I won’t take this little exercise any further, other than to note that to answer the question as to how bats avoid obstacles and capture prey, I would have to figure out a way to hear whatever sound the bats are relying on, determine whether the bats or the prey are emitting it, and at what frequency, since we hear nothing in the lab environment during the experiments with the naked ear. 

So, back to the scientific method and why it’s one of the three critical skills. The iterative process I’ve just described is a good example of the scientific method, with one important piece left out. Let’s say I ultimately determine (correctly) that my bats are emitting ultrasonic clicks that bounce off of obstacles, including prey, allowing the bats to echolocate themselves relative to their environment, thus avoiding collisions while also managing to feed themselves. I perform the experiments several times over, each time carefully noting the results. I then publish a paper that lays out my conclusions, with each step of the scientific method carefully documented: I started with this hypothesis; I made these observations in the field and did this review of the available literature on the subject; I crafted an experiment that allowed me to test my hypothesis; I used control subjects (with and without earplugs) to further test my hypothesis; I carefully analyzed the data I collected; then, based on my analysis, I came up with a conclusion that I believe to be true. Here’s where the piece I haven’t mentioned yet comes into play.

I publish my results as a scientific paper in a scholarly journal. Other scientists read the paper, and then do everything in their power to prove me wrong. It isn’t just their job; it is their responsibility as legitimate scientists, in the same way that it is my responsibility to attempt to poke holes in the results of my colleagues’ findings when they publish their own papers. It’s based on the sacred belief that it’s not about the scientist being right; it’s about the science being right. Is it fun? Do scientists enjoy having their work questioned and pulled apart and quite often proven wrong? Of course not! But they understand that if that doesn’t happen as part of the vetting process, without the scientific method, then science becomes a valueless sham, a card trick, and we’d still be in the Dark Ages, running our fingers along sheep entrails and trepanning people’s skulls to release bad humors and rubbing the lumps on those same people’s heads to predict the future. The sun, subservient body that it is, would still be orbiting the earth, which we’d still believe to be flat. And we’d still be convinced that fossils in the ground were carefully hand-placed 6,000 years ago by a mysterious deity, like a parent hiding Easter eggs. 

***

“Science is more than a body of knowledge; it is a way of thinking.” 

I took that quote from Carl Sagan’s book, The Demon-Haunted World: Science as a Candle in the Dark. It’s an important message, especially today as knowledge seems to be falling out of favor, as educational effort is supplanted by social media ratings and ravings, and as science as a guiding light is characterized as ‘wrong’ (at worst) or ‘merely a suggestion’ (at best). 

Sagan wrote this book in 1996–nearly 30 years ago. Just for the sake of perspective, that’s the year the Palm Pilot, the DVD,  and the first USB interface came out. It’s also the year that an initiative was launched in Menlo Park, California, called Project BackRub. It evolved into another project you may have heard of, called Google.

My point is that around that same time, 30 years ago, Carl Sagan wrote this:

I have a foreboding of an America in my children’s or grandchildren’s time —when the United States is a service and information economy; when nearly all the key manufacturing industries have slipped away to other countries; when awesome technological powers are in the hands of a very few, and no one representing the public interest can even grasp the issues; when the people have lost the ability to set their own agendas or knowledgeably question those in authority; when, clutching our crystals and nervously consulting our horoscopes, our critical faculties in decline, unable to distinguish between what feels good and what’s true, we slide, almost without noticing, back into superstition and darkness.

And if that hasn’t started the hackles rising on your back, Sagan continues:

The dumbing down of America is most evident in the slow decay of substantive content in the enormously influential media, the 30-second sound bites (now down to 10 seconds or less), lowest common denominator programming, credulous presentations on pseudo science and superstition, but especially a kind of celebration of ignorance. As I write, the number-one videocassette rental in America is the movie Dumb and Dumber. “Beavis and Butthead” remain popular (and influential) with young TV viewers. The plain lesson is that study and learning—not just of science, but of anything— are avoidable, even undesirable.

And if that isn’t enough, he finishes that paragraph with this:

We’ve arranged a global civilization in which most crucial elements— transportation, communications, and all other industries; agriculture, medicine, education, entertainment, protecting the environment; and even the key democratic institution of voting—profoundly depend on science and technology. We have also arranged things so that almost no one understands science and technology. This is a prescription for disaster. We might get away with it for a while, but sooner or later this combustible mixture of ignorance and power is going to blow up in our faces.

Science isn’t perfect, and isn’t designed to be, as I hope I explained at the beginning of this essay. But it’s the best tool we have.

If you’re not familiar with Carl Sagan, let me help. He was an astronomer and science communicator, along the lines of Neil deGrasse Tyson and Bill Nye. He led the effort to assemble the content that was inscribed on the golden record that is attached to the Voyager spacecraft, and among his many books he wrote the novel Contact, upon which the movie of the same name starring Jodie Foster and Matthew McConaughey is based.

Sagan took the subtitle of his book from a work published in 1656 called A Candle in the Dark. Written by Thomas Ady, the book attacks the witch hunts that were so common at the time as a scam “to delude the people,” baseless attacks on individuals who were believed to have the power to make people sick and to change the weather. Sagan again:

For much of our history, we were so fearful of the outside world, with its unpredictable dangers, that we gladly embraced anything that promised to soften or explain away the terror. Science is an attempt, largely successful, to understand the world, to get a grip on things, to get hold of ourselves, to steer a safe course. Microbiology and meteorology now explain what only a few centuries ago was considered sufficient cause to burn women to death.

As I have said numerous times in episodes of The Natural Curiosity Project, science has never claimed to be right, only that it will be more right tomorrow, and even more right the day after that. Every day yields wonders and insights in the quest to understand how the world works. Yet today, today, science is attacked by those who refuse to understand what it represents. It’s one thing for scientists to attack their own work using the tenets of the scientific method; it’s another thing entirely for others to attack it without merit. As Sagan says,

Not every branch of science can foretell the future — paleontology can’t—but many can and with stunning accuracy. If you want to know when the next eclipse of the Sun will be, you might try magicians or mystics, but you’ll do much better with scientists. They will tell you where on Earth to stand, when you have to be there, and whether it will be a partial eclipse, a total eclipse, or an annular eclipse. They can routinely predict a solar eclipse, to the minute, a millennium in advance. You can go to the witch doctor to lift the spell that causes your pernicious anemia, or you can take vitamin B12. If you want to save your child from polio, you can pray or you can inoculate. If you’re interested in the sex of your unborn child, you can consult plumb-bob danglers all you want (left-right, a boy; forward-back, a girl — or maybe it’s the other way around), but they’ll be right, on average, only one time in two. If you want real accuracy (here, 99 percent accuracy), try amniocentesis and sonograms. Try science.

Toward the end of his book, Sagan has this to say about education:

Education on the value of free speech and the other freedoms reserved by the Bill of Rights, about what happens when you don’t have them, and about how to exercise and protect them, should be an essential prerequisite for being an American citizen—or indeed a citizen of any nation, the more so to the degree that such rights remain unprotected. 

If we can’t think for ourselves, if we’re unwilling to question authority, then we’re just putty in the hands of those in power. But if the citizens are educated and form their own opinions, then those in power work for us. In every country, we should be teaching our children the scientific method and the reasons for a Bill of Rights. With it comes a certain decency, humility and community spirit. In the demon-haunted world that we inhabit by virtue of being human, this may be all that stands between us and the enveloping darkness.

Science is real, and it is as accurate as anything can possibly be BECAUSE it is designed to be ferociously self-critical. What if our political system worked the same way? Wow—what an amazing thing THAT would be!

It warms my heart to see that none other than Carl Sagan believes in the importance of the three skills with which I started this essay. Yet, caution is called for. As we enter yet another period of political uncertainty and divisiveness, perhaps it is good that I end with this line from Sagan’s first chapter: 

The candle flame gutters. Its little pool of light trembles. Darkness gathers. The demons begin to stir.