by Bill Nye
In my world, things are still resonating. Many years ago, in 1980, I joined The Planetary Society, partly due to the class I had taken with Carl Sagan. In 1983, the society sponsored a field trip to Belize, to the rim of the Chicxulub crater, to collect rock samples; recently, a group of researchers asked to look at those samples and reanalyze them. Maybe they contain more clues about the mass extinction 65 million years ago. Today, I’m the CEO of The Planetary Society that Professor Sagan cofounded. The society’s sunlight-driven spacecrafts, LightSail®-1 and -2, are directly based on an idea that Professor Sagan introduced on The Tonight Show. And now I advocate for asteroid detection and deflection missions to keep us from getting wiped out by a rock from space, like those poor ancient dinosaurs. Each idea leads to a deeper understanding of our world, which leads to more knowledge about how we can protect and improve our world. The work of scientists, explorers, and researchers of the past resonates in the work that we undertake today, just as our actions shape what future generations know and do. No pressure.
In 1993, I wrote a kid’s book called Bill Nye the Science Guy’s Big Blast of Science. It includes an explanation of the greenhouse effect, in which I compare Earth with the closest planet, Venus. On Earth, the global average temperature is about 15°C (58°F). On Venus, the average temperature is about 460°C (860°F). Venus is closer to the Sun, but that doesn’t explain the drastic difference; it gets twice as much sunshine, but it is also covered with clouds that reflect twice as much energy back out to space. What really sets Venus apart from our planet is its atmosphere, which is 90 times as thick as Earth’s and made almost entirely of carbon dioxide. All that CO2 produces a super-greenhouse effect, and as the result is a world where even the coolest day would melt a lead fishing weight into a puddle.
Comparing Earth with Venus is a pedagogical path that Carl Sagan took us down when I was his student 2 decades earlier. Sagan and climate scientist James Hansen realized that the greenhouse effect explains the other planet’s extreme temperatures. Later they connected the Venusian studies to the possibility of climate change on Earth. As with asteroid impacts and nuclear winter, Sagan found the connection between two seemingly disparate ideas and brought a distant discovery home.
I’ve been fighting the climate-change fight for more than 23 years now, along with many others out there, the full-time climate scientists. Hansen, the former director of the NASA Goddard Institute for Space Studies, did an early study conclusively showing that carbon dioxide produced by human activity is making the world get warmer faster than at any time in the past few hundred thousand years. Michael Mann at Pennsylvania State University produced the famous “hockey stick” graph illustrating the world’s temperature over the past several thousand years. Earth’s overall temperature was steady for millennia, but now—whoosh—it has shot up swiftly in just the last 250 years. Gavin Schmidt, who succeeded Hansen at the Goddard Institute for Space Studies, advances and refines our climate models by the day. But in a world filled with people who willfully promote misinformation to further their own agendas, somehow it is still a fight to get this reality taken seriously. Does that mean we should give up? Should we sit back and let those people destroy our future so that we can say, “I told you so”? Of course not. What it means is that we need to embrace the Sagan approach even more vigorously. Take the long view. Be resolute but remain optimistic. Relate ideas in ways that people understand through clear storytelling and personal connections. Look for ways to build small actions into bigger effects. Be a regular force that resonates.
What I want to do is get everybody in the United States, everybody in the world, on board with the exciting opportunities. We don’t want our greenhouse effect to get away from us. As Sagan warned, we do not want to be like Venus. We can produce clean electricity in new ways. Sunlight and wind energy can be harnessed with existing technologies. There’s tremendous energy in the primordial heat of Earth, which we can access just by drilling down a few hundred or even just tens of meters. And here’s something that’s worth remembering: You can’t outsource the erection of a wind turbine tower. You can’t install a power transmission line’s support towers anywhere but where the transmission line is. The jobs to create the renewable economy would be here on native soil. We’ve seen a recent eruption of populist politics around the world, propelled in part by complaints about the loss of local control of the economy. Well, if you want locally produced energy, you are not going to do better than wind, solar, geothermal, and tidal energy. It’s yet another instance in which the best, nerd-certified solution ends up benefiting everyone.
A year after I started The Science Guy series, Sagan was diagnosed with blood cancer. He died 2 years later. It was a huge loss for the world. He was a passionate advocate not just for science but for the scientific way of thinking. He was the nerd’s nerd, but he also had a disarming common touch, an approachable quality that would draw you in when he was chatting with Johnny Carson. People wanted to hear what he had to say. They naturally resonated with his ideas. I’m sure he would have continued to be a powerful voice motivating people to step up and deal with climate change. We could use his help right now, but this resonant process doesn’t depend on just one person. It depends on all of us.
Part of the reason for this book is to enlist your help in making that happen—getting you to be part of the resonance. Help people link extreme weather events with the global warming that makes those kinds of events more likely. Help people understand that renewable energy comes with local control. Connect the inspiring discoveries of space exploration with the things we now understand about the danger of rapid climate change on our own planet. Making these conceptual and personal connections is a very Carl Sagan way of communicating the science. I’m sure it works, because I’ve seen it work.
One of the biggest roadblocks to getting the message out is doubt. Here, too, I draw inspiration from Carl Sagan. I often hear people use the words “skepticism” and “denial” interchangeably (especially among those who refuse to acknowledge climate change), but these two words are worlds apart. Skepticism is a discipline. It’s a component of critical thinking that helps to keep you from fooling yourself or allowing yourself to be fooled; Sagan wanted us all to carry a “baloney detection kit.” Denial, on the other hand, is like a lock on the tool kit that keeps you from thinking about ideas you don’t like.
The professional denial business pretty much started with cigarette companies. Tobacco companies hired scientists who were careful to say that they couldn’t be 100 percent sure about anything having to do with cancer and cigarettes. They explained that it’s their business to develop hypotheses and continually question accepted truths. The denial community exploited that aspect of scientific inquiry in an amazingly deceptive way: If there’s a 5 percent chance that your friend’s lung cancer was not caused by cigarettes, they’d say, then you can’t prove that cigarette smoking is dangerous. They twisted nerd honesty to their own ends. The underlying message was: focus only on the doubt and don’t think too much. It is a way to prevent people from making otherwise obvious connections.
There must always be uncertainty in science, so there are always these kinds of vulnerabilities. It’s not just climate change; there’s also the opposition to vaccination, the irrational fears about genetically modified organisms (GMOs), all the way up and out to those on the fringe who think the Moon landings were faked. The way we will get past all these manufactured doubts is by exposing people to some important critical-thinking skills. In this example, consider how difficult it would be for landing-fakers just to create all the paperwork that the space program generated. That alone would have been more trouble than landing on the Moon! Critical thinkers can recognize when they are being deceived or manipulated. I urge you to promote critical thinking and practice it every chance you get. Set it out into the world and help it spread. I was lucky to grow up in a family that treated the scientific method as the normal, everyday way to think through problems. Not everyon
e is so fortunate.
Perhaps it was easier during the Cold War, when Carl Sagan was researching and I was growing up. Back then, embracing science felt like a matter of life or death, because research led to remarkable new weapons. A sense of crisis forced people to put differences aside. Today, science and technology are more advanced than ever, but many of us often fall into the traps of apathy and doubt. It falls heavily on us nerds to rekindle a sense of shared purpose and common benefit. Commitment to spending on science and technology requires public support. Progress requires collective investment of our intellect and treasure—brains and money. This is the downside of resonance: Destructive impulses from the top down and from the bottom up can shake the whole system, too. In the 1980s, the Reagan administration sidetracked us scientifically. The president symbolically removed the solar panels from the roof of the White House. His people did not take AIDS or acid rain seriously at first. They gutted vital basic research programs.
The current antiscience and antiexpert movement has been decades in the making. Now we need to work hard to turn things around. We nerds all have to use our big-picture point of view to make those crucial personal and conceptual connections—to amplify our influence whenever and wherever we can. We have to write, speak, teach, publicize, and do anything we can to resonate with the wider world. For me, the most profound discovery ever made by us humans is this: You and I, and everything we can touch and see, are made of the same materials and driven by the same energy as everything else in the universe. We are one with each other, with our planet, and with the cosmos. We all resonate to the same beat, and if we put something beautiful into the world, it can spread and grow.
CHAPTER 16
Critical Thinking, Critical Filtering
When I was a kid and I wanted to look up an odd or obscure fact or a piece of information, like Millard Fillmore’s political party affiliation, I hit the books—the actual paper books—in a library. Or in high school if I wanted to know the atomic number of rubidium, I looked it up in the Encyclopedia Britannica, or if I was feeling hardcore, the Chemical Rubber Company Handbook of Chemistry and Physics (the ol’ CRC). Nowadays I just pull out my laptop or my fancy new phone and go to Google. Then 586,000 results and 0.46 seconds later, I learn that Fillmore was the last president affiliated with neither Democrats nor Republicans, lucky guy. And 146,000 results tell me that rubidium, symbol Rb, has an atomic number of 37, which means that it contains 37 protons. Checking the density, I found both 1.53 grams per cubic centimeter and 1.532 grams per cubic centimeter.
Those are a lot of data to absorb, and they are just a tiny portion of what came up. Meanwhile, I had to decide which details mattered to me and which sources I trusted. What about those two different values for density—is the first number rounded from the second one? If you were so motivated, you could dig through a dozen sources, see who did the original measurements, and probably figure out who then rounded it down. In the old days, you had to look things up in just a few reliable sources to save time. In today’s data-soaked world, though, you easily can do quite a bit of extra sleuthing. Information comes at us so quickly now that the challenge is not speed and efficiency but figuring out which of those 146,000 results contain the highest-quality answers. Although you and I largely trust the Google search algorithm to put the good information up high, we don’t necessarily expect Google to put the best information up at the very top. And how much do you know about the workings of that search algorithm, anyway?
Information is the currency of the nerd perspective, so the rush of online info is enormously empowering. But yikes, does it have some troubling features. No search algorithm is foolproof, especially since people are constantly trying to game the system, hoping to take advantage of a version of a mob mentality. YouTube videos from hucksters and hoaxers can appear as slick as those from major academic and government institutions. And just look at the mess on Facebook, where friends’ comments, strangers’ comments, sponsored content, legitimate news, and commercial propaganda mingle freely—and confusingly. With so much sense and nonsense flying around, who can sort out what is true and what is not? We need a sophisticated filter that lets through only high-quality information.
A top-down approach to filtering, with someone or some system deciding what is or can be posted online, is not a good answer. Restricting access to information in any way would almost certainly be a terrible development. I wouldn’t trust that approach even if the nerds were in charge, and it’s a good bet that they would not be. Governments could simply blot out news they don’t like, in the way that the Soviet Union tried to suppress details about the Chernobyl disaster in 1986 or the way the North Korean government still restricts most Internet content. Whole classes or parts of the world might be cut off, able to connect only with what looks like real information but is actually false. It would take the problem of information quality to an even higher level.
The real solution—the only meaningful solution—is to be able to evaluate the data yourself and tackle the problem from the bottom up. In the 21st century, data-filtering literacy is therefore as vital as science literacy. Or you can call it by the more common term “critical thinking.” Either way, it is a defense against information overload and a powerful technique to overcome confirmation bias. Carl Sagan referred to a critical thinker’s checklist as a “baloney detection kit.” For me, there are three key ideas in thinking critically about a claim that you come across. First: Is it specific? Second: Is it based on the simplest interpretation of the phenomenon? And third: Has it been independently verified? You could even boil it all down to a single statement: “Prove it!” Let me show you what I mean.
Start with specificity. A meaningful claim should be precise enough that we can agree on what we’re talking about. If it passes, it is something we can test. If it fails, if it’s not specific, we can stop right there. A vague claim is going to be either useless or wrong—guaranteed. Here’s the classic example: Someone tells you, “We live on a great big ball.” Put aside what you’ve been taught; why should you believe it? I mean, that is an extraordinary claim. A big ball? Really? If you go walking around in your neighborhood, you’ll see that things look pretty flat in the big picture. Even if there are large mountains nearby, Earth still looks like a flat world with some big and small bumps. It certainly does not look like a ball. If you look out toward the horizon, you might conclude that the world is flat but very large. Anything beyond the horizon is just too far away to see. The sense of flatness is especially strong if you’ve ever stood on the deck of a ship surrounded by ocean. The horizon really does look like it is just a faraway edge of a flat disk of Earth. Based on those kinds of direct personal observations, it does not seem likely or even reasonable that the Earth is round.
But the claim that the Earth is round is succinct and precise. We can easily test it. We can observe the Earth’s shadow on the Moon during an eclipse. We can watch ships sail over and below the horizon, then turn around and return to port. We can build spacecraft and take pictures from high above the Earth’s surface. “We live on a ball or sphere” is a testable statement, and we can prove it in a number of ways. The proofs are so straightforward that Greek natural philosophers deduced the roundness of the Earth more than 2,000 years ago. Despite pop-culture myths, educated people in Western culture have accepted the roundness of the Earth ever since. (It’s another piece of modern misinformation. The idea that many or most people once believed the Earth is flat is a specific claim that is easily debunked by looking at writings from the Middle Ages.)
Next, let’s consider the principle of simplicity. This is tied to what is often cited as “Occam’s razor.” It’s the idea that a simple explanation for a phenomenon is more likely to be correct than a complicated one. William of Occam was a 14th-century English philosopher who advanced this idea as part of a broader argument against abstraction and complexity in the world. It’s a reliable road to reason. Try this: “I got a call from my dead aunt today. I saw her
number on my caller ID, but when I answered the phone, there was no one on the line. I think it was her ghost.” Well, it could be that dead people leave behind invisible ghosts (which nobody has detected) and that ghosts can make phone calls (for no knowable reason) and that when they do, they trigger the caller ID of the number they used when they were alive. Or it could be that the phone company assigned your dead aunt’s number to someone else, and when you answered, the stranger with the new number hung up.
Which explanation is more likely? I like this example because it is drawn from real life. Someone tried to sue a skeptic friend of mine who debunked this very claim in this very fashion.
Occam’s razor is also excellent for cutting down (sorry . . .) conspiracy theories. If someone tells you that doctors, scientists, pharmaceutical companies, government agencies, and journalists are all working together to cover up the dangers of vaccines, think about the complexity of the coordination needed, and all the cover stories required, to make that work. Think about the motivations of all the people involved. Then consider the alternative interpretation: People naturally look for explanations when things go wrong with themselves or with their children, and vaccines—something injected right into the body at about the same time in life as a diagnosis of autism is reached—are an obvious place to project fears when there is no obvious cause. Which explanation is simpler? Which one just makes more sense?
Finally, there’s the matter of testability. Specificity and simplicity help get you there; without them, you don’t even know what it is you are trying to test. But not all things simple and specific are true, so claims that make it this far still require verification. I’m pretty sure you don’t have the time and resources to test every reasonable-sounding piece of information on the Internet. Fortunately, many other people have already pioneered the “prove it” process for you; all you have to do is follow their trails in an attentive manner. Even Wikipedia, the busy (or lazy) person’s encyclopedia, is full of references and lists of related sources (60 of them in the entry for rubidium, for instance). Information that has no source is immediately suspect because you cannot know how or if it was tested. When you do see sources, see if they point back to a primary journal, textbook, or researcher at a major research institution. At that point, you can start to rely on expertise—that is, on the people on the high side of “everybody knows something you don’t.” As with the examples I mentioned at the beginning of the chapter, the Internet can make this vetting process quick and easy—once you practice it a little.