The Skeptics' Guide to the Universe

Introduction

Spock lied to me.

And it wasn’t just Spock (well, actually Leonard Nimoy as the host of the popular but dubious TV show In Search of…) who lied but the media, journalists, corporations, politicians, salespeople, and just about every adult and authority figure in my life. Some were deliberately lying, while others were fudging the truth for what they thought was a good purpose. Most, however, were simply mistaken, misinformed, or self-deluded and were spreading what they assumed was the truth but were just the lies others had told them.

We all start as children believing pretty much whatever we’re told. The gulf of knowledge and experience between adults and young children is so great that to a child, any adult is perceived as the ultimate authority on any topic. As we mature we realize that not all adults agree with each other, so some of them must be wrong. We become more sophisticated in our choice of authority figures, but we still tend to rely on others to know what to think—on experts, leaders, religious figures, celebrities, talking heads, or just “common knowledge.”

Science is another authority. When I was younger I had an intense fascination with all things scientific. Scientists simply had the best stories to tell: how gigantic dinosaurs roamed the earth millions of years ago; how our primitive ancestors made tools out of stone; how the sun, Earth, and moon formed billions of years ago; how a single cell develops into a human; and how life evolved from simple creatures to everything we see today.

My brothers and I watched every TV science documentary we could find, instinctively knowing they were much better than any sitcom or hokey drama. Mixed in with the science documentaries, however, were what I now know to be pseudoscience or fake documentaries. This is where Leonard Nimoy comes in, as the host of the popular series In Search of…, which aired from 1977 to 1982.

In each episode Nimoy would narrate how scientists had discovered that aliens built the Nazca lines (the enigmatic drawings etched into the sands of the Nazca desert in Peru) or were on the verge of discovering a large creature living in Loch Ness. He built a compelling case (or so I thought) for the existence of extrasensory perception, Atlantis, and Bigfoot. Just like the hosts of the other science documentaries we would watch, he would show us evidence and interview experts. We ate it up.

At the same time, we were being raised as good Catholics. Looking back, it amazes me how, as a young child, I completely compartmentalized my belief in evolution and Adam and Eve. Abraham, Mary, and Joseph were historical figures to me, taught with the same authority as were the exploits of George Washington. In church, faith was taught as an absolute virtue, so being a good person meant simply believing.

This exciting world of fantastic narratives that society had built in my head—evolution, Genesis, Loch Ness monsters, and many more—was not sustainable. Eventually I had to sort out the apparent conflicts among these various narratives. The claims of evolutionary biology and a literal interpretation of Genesis could not both be true at the same time. This meant questioning and doubting. I had to figure out which narratives to believe and which ones to reject.

This is the essence of skepticism: How do we know what to believe and what to doubt?

Once you begin to ask questions like “How do we actually know anything?” our beliefs start to fall one by one. How would we know if aliens were visiting Earth or if sticking needles in special points on the body could cure disease? This questioning doesn’t always end well, as some people will choose to reject science so they can maintain their belief in aliens or miracles. Others keep questioning. This process is never done—it is an endless journey.

The question is, How far will you go, and in which direction will you head? This is ultimately a personal odyssey, but we aren’t completely alone. We are part of ever-expanding social rings with which we share our quest for knowledge and understanding. The biggest ring encompasses all of humanity. As a species, we are on a journey of discovery, trying to figure out what to believe and what knowledge is reliable.

Your travels will take you through some interesting and exciting twists and turns. It can be scary. At some point you will confront a belief you really want to be true, that may even be part of your identity, but that does not stand up to close scrutiny. Ultimately this is a journey of self-discovery, and hopefully this book will serve as a guide on that journey. In these pages you will learn about the many ways in which your brain fails, its tendency to prefer nice clean and reassuring stories, the absolute mess that is your memory, and all the preprogrammed biases in your thinking.

You will also learn about the many ways in which society fails, the imperfections in the institutions of science, learning, and journalism. It’s intimidating to realize that we live in a world overflowing with misinformation, bias, myths, deception, and flawed knowledge. We are all children and there are no adults. There are no ultimate authority figures; no one has the secret; there is no revealed knowledge; and there is no place to look up the definitive answers to our questions (not even Google).

We are all struggling through this complex universe just like everyone who came before us.

Fully realizing this essence of the human condition can make you cynical, denying all knowledge. That, however, is just another bias, another narrative to help us deal with the chaos. Cynicism is also cheap—it’s easy just to doubt or deny everything. But it doesn’t get you or society anywhere. Skepticism goes beyond cynicism. While it may start with doubt, that’s the beginning, not the end. There isn’t any definitive or ultimate knowledge (no Truth with a capital T), but we can grind out knowledge about the world that is sufficiently reliable for us to treat it as provisionally true and act upon it. We can, for example, send probes to Pluto and get back gorgeous pictures of a place that was previously entirely mysterious. If our knowledge of the universe wasn’t at least to some degree true, then our efforts to see Pluto wouldn’t have been rewarded with beautiful images of this distant and frozen world.

So, while we cannot trust the stories we are told, tradition, faith, convenient or reassuring narratives, charismatic figures, or even our own memories, we can slowly and carefully build a process by which to evaluate all claims to truth and knowledge. A big part of that process is science, which systematically tests our ideas against reality, using the most objective data possible. Science is still a messy and flawed process, but it is a process. It has, at least, the capacity for self-correction, to move our beliefs incrementally in the direction of reality. In essence, science is the process of making our best effort to know what’s really real.

Combined with science are logic and philosophy, which are simply ways of thinking about things really carefully, to at least make sure there is no internal contradiction. Valid reasoning, careful and systematic observations, recording and counting all data (not just the data we want), and trying to disprove our own conclusions is a lot of work, but it moves us forward on our journey. Skeptics combine knowledge of science, philosophy, human psychology, and all the flaws and biases of human thinking to evaluate all claims and beliefs, especially their own.

I took a major step in this direction when I watched the series Cosmos, cowritten and hosted by Carl Sagan. It was perhaps the first time I saw a science documentary that didn’t just state facts but explored how we know what we know. Sagan investigated what we thought in the past, and how new discoveries changed our thinking. In one episode he dedicated a segment to questioning the alleged evidence for alien visitation. That segment was a revelation. If there was ever a moment when I tipped over into becoming a skeptic, that was it. Here was a respected scientist carefully arguing with logic and evidence why the case for UFOs was not compelling. In fact it was utter crap. That meant that all those alien visitation documentaries (including half of the In Search of… episodes) were not just wrong, they were nonsense. I felt betrayed.

Those documentaries weren’t real science, they were what Sagan called “a cheap imitation.” They were pseudoscience. Wow—what other claims were as flimsy as the evidence for UFOs? The dominoes started to fall.

My journey took another step when I encountered creationism, the denial of evolution. This blew me away. By then I’d read dozens of books and articles on evolution, which was one of my favorite scientific topics, and I was well versed in the mountains of evidence scientists had accumulated showing that life on Earth has evolved.

Now I was reading or listening to people who denied all this evidence, denied that evolution had happened at all, or at least how scientists claim it had happened. I couldn’t help but slow down and take a close look, like viewing a horrific accident on the highway. The arguments of creationists ranged from silly to sophisticated, but ultimately they were all flawed. I tried my best to understand where they went wrong. At first I naively believed that if I could just explain to creationists (when I had the opportunity, during random in-person encounters) the flaws in their reasoning or the factual errors in their premises, I could change their minds. While this isn’t impossible, it proved far more difficult than I had imagined.

Something was going on, something I didn’t understand. I went to college as a science major struggling with all of this and my rapidly waning faith. I was well on my way on a skeptical journey that continues to this day, three decades later.

This obsession with understanding how we know what we know and how human belief goes off the rails has become my life’s work. I love the process and findings of science and working out how to explain all of this to others. When I discovered that there was an active skeptical movement of people with the same set of obsessions, I never looked back.

One day my close friend and fellow skeptic Perry DeAngelis noticed that while there were dozens of skeptical groups around the country, there were none in our home state of Connecticut. We should start our own group, he suggested, and I knew instantly we were on the right path.

We were joined by our mutual friend Evan Bernstein and my two brothers, Bob and Jay. Those are the same brothers who watched In Search of… with me as teenagers. We helped each other through those early years spent transitioning from believing all manner of nonsense to being skeptics. I still remember (well, as much as our flawed memories can record anything) the day I told Bob that I no longer thought ESP (extrasensory perception) was real. He was shocked, but a thirty-minute conversation was all it took to lay out the gaping flaws in the evidence.

Together, in 1996, the five of us created the New England Skeptical Society. We were content (sort of) to print a newsletter and host local lectures. We would have loved to be more involved, but we all had day jobs. We did go on investigations, attend UFO conventions, and confront proponents of all sorts of pseudoscience. Those were the years when we “earned our bones.” We also had the opportunity to meet scientists, philosophers, magicians, and other skeptical activists.

Then social media hit with full force. In 2005, when podcasting was a new thing, I had the idea of starting a weekly science and critical thinking podcast. We settled on the name The Skeptics’ Guide to the Universe (inspired by the Hitchhiker’s Guide to the Galaxy series of books we all love)—SGU for short. As of writing this book, we are still going strong.

Along the way we picked up a fellow traveler, Rebecca Watson, who cohosted the show for nine years. We also lost Perry, who died in 2007 from complications of scleroderma. We were joined by a new Skeptical Rogue (as we call ourselves) in 2015, Cara Santa Maria.

Every week the five of us try to make sense of what seems like an increasingly crazy world. The internet and social media have been a mixed blessing, allowing us to teach science and critical thinking to a far wider audience but also facilitating the spread of misinformation like never before.

In the last two decades, while we’ve been fighting for science and reason, it seems like the stakes have only gotten higher. My own profession—medicine—has been thoroughly infiltrated by the pseudoscience of so-called “alternative” medicine. The very process of science is under attack. There are entire movements dedicated to denying and opposing the hard-won fruits of scientific discovery. And now it seems that truth and facts themselves are easily tossed aside as an inconvenience. There are those who think, with good reason, that humanity is stepping back from the Enlightenment to huddle in echo chambers of comfortable, or at least familiar, beliefs.

This is a generational struggle, one that will likely never end.

Like in the universe of Douglas Adams, we have created this helpful and reassuring guide, which will prove invaluable on your skeptical journey, because the world is actively trying to deceive you and fill you with stories and lies. The forces of ignorance, conspiracy thinking, anti-intellectualism, and science denial are as powerful as ever.

It’s true that we have to struggle with these incredibly flawed meat machines in our skulls. But we are standing on the shoulders of giants. A lot of smart people over a very long time have thought and argued carefully about the nature of reality and our ability to understand it. We have some powerful tools, like science and philosophy. We do know stuff, and we have ways of making sense of it all.

Don’t panic. This whole notion of thinking for yourself and questioning everything is actually quite fun and empowering. We can do this together.