Astrophysicist Neil deGrasse Tyson warned over the weekend that Republican policymakers who deny science were "unraveling" a tradition of fact-based governance.

During a CNN interview, Tyson made an example of those who insist on denying that humans contribute to climate change.

"If anyone utters the words, 'It's just a theory,' it means they're missing a piece of their education where they do not fully understand what science is and how and why it works," Tyson explained to CNN host Fareed Zakaria. "I try not to beat folks over the head in power because they are duly elected by a population that wants their leadership to serve them."

He added: "So as an educator, I look at the electorate and I say, if you're going to make an informed decision, not only about the country's future but especially about your own future, it would be greatly enhanced by just learning how knowledge is acquired and how it is affirmed in the scientific arena."

Tyson lamented that some people "accept what people tell them or think that they can deny an objectively established scientific truth."

"I don't mind that," he continued. "In a free country, think what you want. But if you now rise to power and have jurisdiction over legislation and you pivot that on what you don't know about how the world works, that's a recipe for disaster."

"It's the beginning of the unraveling of an informed democracy."

Watch the video below from CNN, broadcast May 7, 2017.