When you get into an argument with someone and they make a statement as though it is a fact, the natural thing to do is ask a simple question: Can you prove it?
So it was at Tuesday's debate between Bill Nye, the executive director of "space interest" organization The Planetary Society and the man behind the famous Bill Nye the Science Guy TV show, and Ken Ham, president of creationism organization Answers in Genesis and the head of the Creation Museum in Petersburg, Kentucky, where the debate was held.
The event was framed around whether creationism is a viable model for explaining the origins of the Earth, which sets up the discussion in such a way that Ham, who believes creationism is a viable model, would be forced to take the defensive. But he moved beyond those confines, and the debate began to focus on whether one person could prove or disprove anything to the other.
See also: Watch Live: 'Science Guy' Bill Nye Debates Creationist on Evolution
That started when Ham asserted that creationism was not only an acceptable option for explaining the beginning of the planet, but the only option.
"Creation is the only viable model of historical science confirmed by observational science in today's modern scientific era," Ham said.
That was Ham's key message throughout the night, and within it is another message he tried to get across throughout the evening: That there is a difference between science based on what we can observe today and science that tries to detail what happened in the past, such as any scientific theory that can prove the Earth is several billion years old as opposed to a mere 6,000 years young, as Ham and Young Earth Creationists believe. It is essentially a "pics or it didn't happen" theory, a statement that says if you weren't there, you can't prove it, something he also said throughout the night.
"When we're talking about origins, we're talking about the past," Ham said. "We weren't there. You can't observe that. Whether it's molecules-to-man evolution or whether it's a creation account. I mean, you're talking about the past. We like to call that origins or historical science, knowledge concerning the past. Here at the Creation Museum, we make no apology about the fact that our origins or historical science actually is based on the Biblical account of origins."
Nye poked holes in the idea that the Earth is 6,000 years old by providing evidence for how scientists have dated trees that are older than that, and such evidence seemed to be one part of his three-pronged platform.
The science guy also devoted some time to challenging Ham's notion that there is a difference between "observational" and "historical" science.
"This idea that you can separate the natural laws of the past from the natural laws we have now I think is that the heart of our disagreement," Nye said. "I don't see how we're ever going to agree with that if you insist that natural laws have changed. It's, um, for a lack of a better word, it's magical."
But Nye's third prong brought the debate back to the question at hand, whether creationism is a viable scientific model to teach people about the origins of the planet. If the Bible is going to be used as a valid scientific textbook, Nye wanted some evidence that its theories could explain different elements of the world. He requested such evidence again and again, but was not satisfied.
"The Ken Ham creation model does not have this capability—it cannot make predictions and show results," Nye said.
The 2.5 hour debate, which you can watch below and was moderated by CNN's Tom Foreman, stayed on topic for the most part, but did take some brief but eyebrow-raising turns along the way. At one point, viewers found the two men debating the morality of fish. At another, Ham appeared to suggest that the theory of evolution once supported racism. Ham also said he wants "children to be taught the right foundation, that there's a God who created them, who loves them, who died on the cross for them, and that they're special, they're made in the image of God," which contradicts the idea of a separation between church and state.
Though plenty of people were watching the debate's twists and turns, many were also having their own debates on Twitter. #creationdebate was a trending topic in the United States throughout the segment, and people had opinions about every aspect of the event.
I hope Neil deGrasse Tyson bursts through the wall like the Kool Aid guy and sets up a third podium #creationdebate
— Katharine Heller (@spkheller) February 5, 2014
Oh my god Ken Ham is mansplaining science to Bill Nye the SCIENCE GUY. #creationdebate
— Rebecca Eisenberg (@ryeisenberg) February 5, 2014
Shorter Ken Ham: I didn't see the mailman deliver my mail. Neither did you. So God delivered my mail. #KarlMaloneIsGod #creationdebate
— Thomas Haire (@THrants) February 5, 2014
Those opinions constantly shifted the online conversation, and the on-stage debate seemed to bounce from one topic to another as the minutes wore on, but then a question during the final segment of the show tied it all back to what seemed to be the underlying topic: what could one side prove or disprove to the other?
The questioner asked what evidence, if any, would change either Nye or Ham's mind about their world view.
Nye answered that a single piece of evidence supporting creationism would sway him immediately. Ham responded differently.
"No one's ever going to convince me that the word of God is not true," he said.

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