Astrophysicist Neil deGrasse Tyson has released a video urging Americans to change how they relate to science.

Tyson posted the four-and-a-half minute video on his Facebook page, alongside this written note:

Dear Facebook Universe, I offer this four-minute video on "Science in America" containing what may be the most important words I have ever spoken. As always, but especially these days, keep looking up. – Neil deGrasse Tyson

Tyson's message in the video centres on what he sees as a worrisome decline in scientific literacy in the US.

"Science is a fundamental part of the country that we are," he says in the video. "But in this, the 21st century, when it comes time to make decisions about science, it seems that people have lost the ability to judge what is true and what is not."

That shift, he says, is a "recipe for the complete dismantling of our informed democracy".

Tyson's speech is interspersed with clips of political debates and news. The video cuts to a clip of Vice President Mike Pence, then a congressman, speaking on the floor of the House of Representatives.

"Let us demand that educators around America teach evolution not as fact, but as theory," Pence says in the clip.

The role of science, Tyson says, is to provide the factual grounding for politics. The role of politics is to decide what to do about those facts.

You can watch the video in full below.

This article was originally published by Business Insider.

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