Thirty minutes into Hillary Clinton’s speech accepting the Democratic Party’s nomination for president, she made a simple admission that, in 2016, should not be remarkable but somehow was. “And, I believe in science!” she exclaimed. And then she laughed uncomfortably as the crowd applauded, perhaps uncomfortable themselves.

This is bizarre, because in 2016, stating a belief in science should not be a line in a presidential candidate’s speech. Science is not up for debate. Science is not something one chooses to believe in because it flatters one’s partisan preferences. Science is a fact, and either people acknowledge reality or they do not.

The majority of Americans accept science like electricity and gravity. If a ball is dropped, most people won’t dispute that it will fall to the ground (accelerating at a rate of 9.8 meters/second2). Somehow, though, much of the country still chooses not to accept the scientific facts of evolution and climate change and vaccinations.

According to Gallup polling about evolution, “the percentage of the U.S. population choosing the creationist perspective as closest to their own view has fluctuated in a narrow range between 40 percent and 47 percent since [1982].”

The year 2015 was a record one for warm temperatures, but only 49 percent of Americans believe that was because of man-made climate change. (Even though there’s still significant—public—debate about what’s causing global warming and when it will start happening, 90 percent of Americans do believe it will happen in some form.) The subsequent line in Clinton’s speech was: “I believe climate change is real and that we can save our planet while creating millions of good paying clean energy jobs.”*

Despite the public’s doubt, the scientific community is overwhelmingly united on both of these issues.

It’s the majority of Clinton’s opponents who don’t accept science. That half of the country that doesn’t believe in climate change? Mostly Republicans: 72 percent of Republicans believed that natural changes were responsible for last year’s temperature spike while 72 percent of Democrats believed it was caused by humans.

“The concept of global warming was created by and for the Chinese in order to make U.S. manufacturing noncompetitive,” Donald Trump tweeted in 2012, and more recently he’s called it a “hoax.”

His running mate, Mike Pence, doesn’t believe in evolution.

And Trump is even wrong on vaccines, which have been less of a partisan football. “I’ve seen it. … You take this little beautiful baby, and you pump— it looks just like it’s meant for a horse, not for a child … a child went to have the vaccine, got very, very sick, and now is autistic,” he said during a 2015 Republican debate. The autism-vaccine link is myth, long since debunked, ginned up by a con artist who faked a study in order to make money.

It’s terrifying that Clinton was able to score political points by saying that science is real, but it’s because in today’s political landscape, that is not a guaranteed stance. Republicans have already tested what happens when they agree with Clinton’s beliefs.

“To be clear. I believe in evolution and trust scientists on global warming. Call me crazy,” tweeted Jon Huntsman a former governor of Utah and 2012 presidential candidate. Huntsman didn’t win a single state and decided not to run for president again, because he felt like the Republican Party had left him.

Even while the current Republican Party ticket shows a stunning denial of fact, revisiting those numbers shows that outright rejection of science is not universal in party base. Only 10 percent of Americans overall don’t believe in climate change. Even if those 72 percent of Republicans incorrectly attribute global warming’s cause to nature, they still acknowledge that it is happening.

What was remarkable about Clinton’s performance on Thursday night was her occasional nonchalance. When she delivered her line about science, the subsequent chuckle read as “I cannot believe I get to be a hero for this.” As we enter the portion of the campaign where Clinton and Trump face off more directly, her measured and fact-based answers—on the economic importance of addressing climate change now or the Environmental Protection Agency’s necessity—could well drive some wavering Republicans into her camp.

Perhaps that’s what she was laughing about.

*Correction, July 29, 2016: Due to an editing error, this story originally misquoted the subsequent line of Clinton’s speech. It has been corrected. (Return.)

Read more Slate coverage of the 2016 campaign.