I've usually found that the class sessions that most effectively push the conversation about skeptical inquiry forward are a happy combination of careful planning, quick connections, and a dash of luck.
Take one Thursday in early October. "Why don't we have class next Monday?" someone asked, innocuously enough.
Several students muttered, "It's Columbus Day," and everyone settled down for the work of the day.
In response to the comments of a student who had already developed a reputation for appealing to claims of elaborate cover-ups by secret organizations, I had brought in "Dead and Alive: Beliefs in Contradictory Conspiracy Theories," a January 2012 Social Psychological and Personality Science article by Michael J. Wood, Karen M. Douglas, and Robbie M. Sutton of the University of Kent. It's a serious slice of statistical research, chock full of data and formulas and complex observations, but my community college developmental writers were able to pick out and grasp the salient ideas: that "conspiracy theories can form a monological belief system: a self-sustaining worldview comprised of a network of mutually supportive beliefs," and that "even endorsement of mutually incompatible conspiracy theories are positively correlated." How is it possible that some people manage to believe both that Princess Diana (of whom most of my students have never heard) faked her own death and that she was murdered? Or that Osama bin Laden (of whom they are well aware) not only recently faked his own death but had also been dead for years? Because "the monological nature of conspiracism...is driven not by conspiracy theories directly supporting one another, but by the coherence of each theory with higher-order beliefs that support the idea of conspiracy in general."
Though the overarching findings here were clear, they elicited typical objections from some students. "That doesn't make sense," they insisted. "It doesn't take critical thinking to realize that two things you believe contradict each other."
"Well," I said, fishing around for some way to connect the phenomenon to something more immediately observable. Aha, I thought. Got it.
"Why don't we have school next Monday?" I asked.
"Columbus Day," the chorus replied.
"Okay, and what are we celebrating?"
"Murdering Indians?" someone offered, provoking a mix of laughter and grim agreement.
"No argument," I said, "but for the sake of the conversation, leave genocide out of it for a minute. What is the holiday meant to be celebrating? What did Columbus do?"
The expected answers came simultaneously. "Discovered America," shouted some. "Proved the world was round," shouted others.
I wrote both of these accomplishments on the board, then asked the class to start unpacking the implications of each. The ensuing discussion yielded a number of insights, among them that proving the spherical nature of the earth required circumnavigation of the globe.
"But wait," someone said. "He didn't make it around the world like he thought he would, because America was in the way."
"But that's why he discovered it," another student responded. "By accident."
"But he didn't know that, right?" someone else added. "Isn't that why Native Americans are called Indians? Because Columbus thought he reached India?"
"Which means he didn't discover it."
(As more voices joined the discussion, I made a mental note to return later to the aforementioned mass exploitation and violence of the 1490s encounter, evidence of earlier European voyages to the Americas, the ethnocentrism implied by claims of "discovering" an inhabited place, the actual historical precedent of knowledge of the earth's shape, and other relevant problems. The students were about to make a more immediate discovery of their own.)
"Okay, so he didn't discover America, but he did reach it. Isn't that what's being celebrated?"
"And he still proved the world was round."
"No he didn't! If he didn't make it around the world, then people only thought he had proved the world was round. It might still have been flat if he didn't actually sail all the way around it."
"Yeah! The only way his trip could have proven the world was round is if he made it all the way back to Europe!"
"But...if he went to America and back..."
And there it was. It became inescapably obvious to the entire class that, totally aside from the question of the accuracy of the claims, a belief that Columbus had discovered America and a belief that he had proven the roundness of the earth were, necessarily, mutually contradictory claims -- both of which nearly everyone in the room had somehow managed to carry with them for decades without recognizing the inherent logical problem.
"Damn!" observed a usually silent student. "That's, like, obvious!"
"So, what, we're all just stupid? None of us thought to question it?"
"Not just us, everybody. All the people who taught us that, and celebrate the holiday, and buy the claims. What the hell?"
An uncomfortable silence followed, broken by our typically conspiracist student. "It's a conspiracy!" he yelled, smiling. Everyone laughed, but out of the moment of humor came an idea. Recalling the analysis by Wood et al., someone suggested that something about the Columbus story might represent a set of "higher-order beliefs" with which the two contradictory claims were "coherent" -- not a belief in conspiracies, but in an ideology that the Columbus narrative supports.
Excitedly, several of the students started generating a list of such ideological beliefs: the idea of discovery, the colonialist impulse, the justification of exploitation and nation-building, the exaltation of the intrepid individual who bucks the status quo, and so on.
Then someone put the brakes on. "But this is just a hypothesis, right? We would need to do research to demonstrate that there really is a whole system of support for those ideas."
"That won't be hard," added another student. "Just look around, you can find that everywhere."
"Wait," another student objected, "wouldn't we actually have to try to find DISconfirming evidence? To avoid confirmation bias? Otherwise we're just going to find what agrees with the hypothesis."
And so on. The conversation was sprawling and messy, but undeniably useful, and the class wrestled with complicated but essential questions about how cognitive and cultural biases can drive interpretation and frame the questions we don't ask as well as our answers to the ones we do.
For my part, I wonder how the session would have gone had it happened in November instead.
Marc David Barnhill is a Critical Thinking / Reading / Writing educator at New York University and the City University of New York whose work sees literacy, skeptical inquiry, and social justice as mutually informing concerns. He has been a presenter and panel participant at SkeptiCamp NYC and at the Northeast Conference on Science and Skepticism, serves on New York City Skeptics’ NECSS Organizing Committee and on Center For Inquiry-NYC’s Campus Advisory Committee and Volunteer Advisory Board, and is a recipient of CFI-NYC’s Freethinker of the Year award. He blogs at marcdavidbarnhill.com, is active on Twitter, and is currently writing a book titled The Promise of Critical Thinking.