For two years, they formed a community of experts, about 1,000 in all, including 300 leading climate scientists inside and outside 13 federal agencies. For two years, they volunteered their time and expertise to produce the Fourth National Climate Assessment.

There is no parallel process to tackle the questions I study; there is no ongoing national racial assessment mandated by a law summarizing the impact of racism on the United States, now and in the future. Still, I can relate to these climate scientists.

From U.S. national assessments to the global assessments of the United Nations Intergovernmental Panel on Climate Change, climate scientists have been pumping out warnings for decades. Each warning about what will happen if there is not “substantial and sustained reductions in global greenhouse-gas emissions” has been more dreadful than the last. I can relate to their continuous stand on scientific certainty, their continuous travel toward scientific discovery, and their quest to cultivate and defend humanity from humanity. “I’m for humans,” the climate scientist Andrea Dutton recently tweeted.

The first volume of their Fourth National Climate Assessment, released last year, concluded that there is “no convincing alternative explanation” for global warming other than “human activities, especially emissions of greenhouses gases.” This year’s second volume, released into the mad dash of Black Friday sales and family reunions, stated, “More frequent and intense extreme weather and climate-related events, as well as changes in average climate conditions, are expected to continue to damage infrastructure, ecosystems, and social systems that provide essential benefits to communities.”

“I don’t believe it,” President Donald Trump said in response. “No. No. I don’t believe it.”

I have heard this before. I can relate.

“No. No. I’m not racist,” Trump has said repeatedly. Evidence be damned.

I feel how climate scientists probably feel when they hear Trump and others disbelieve what their scientific community says is beyond disbelief. Scholars of racism watch as individuals dismiss our scientific consensus as casually as they form a consensus of disbelief. Climate and racial scientists watch as the denials of climate change and racism combine for the denial that “marginalized” communities of color “are expected to experience greater impacts,” as foretold in the Fourth National Climate Assessment.

The disbelievers do not believe that either climate change or racism is real. Or they do not believe they are caused by emissions of greenhouse gases or racist policies. Or they do not believe that regulating them would be better for society.

All this disbelief rests on the same foundation: the transformation of science into belief. It is a foundation built from the economic, political, and ideological blocks that stand the most to lose from the aggressive reduction of carbon-dioxide emissions and racial inequities.

These defensive voices engage in the same oratorical process, attack the credibility of scientists, disregarding their consensus and reducing their findings to personal beliefs.

The effect: Science becomes belief. Belief becomes science. Everything becomes nothing. Nothing becomes everything. All can believe and disbelieve all. We all can know everything and know nothing. Everyone lives as an expert on every subject. No experts live on any subject. Years of intense and specialized training and research and reflection are abandoned, like poor Latino immigrants, like the poor body of our planet.

Instead of trained racial researchers, individuals decide whether they are racist, whether their ideas are racist, whether their policies are racist, whether their institutions are racist. Instead of trained climate researchers, individuals decide whether that worst-ever natural disaster, whether that record temperature, whether that rising sea level is caused by climate change. The great confrontations of our time are not between scientists, but between individual beliefs and scientific knowledge.

Adam Serwer: America’s problem isn’t tribalism—it’s racism

How many Americans, as they strive to be balanced and objective and bipartisan, to bring people together, think they can subscribe to both individual disbelief and scientific knowledge? How many Americans believe there are very fine ideas on both sides of these questions? How many Americans ask, “Do you think racism is still a problem?” or “Do you believe the globe is warming?” as if society should value ignorance in the face of scientific certainty.

I am relatively ignorant about climate science, and about every subject matter outside my own expertise of racism and anti-racism. The ridiculousness of climate-change denial is matched by the ridiculous of asking people like me whether we believe in climate change. The ridiculousness of denials of racism is matched by the ridiculousness of asking whether people believe in the persistence of racism.

And in their ridiculous answers to ridiculous questions, denialists evince more than disbelief. They explain their disbelief using examples in their direct line of sight. They do not trust the far-flung hindsight, foresight, and bird’s-eye view of the scientist. They do not believe the distant averages, likelihoods, disparities, and sweeping histories that show the ravages of racism and climate change on society. If it is not happening within their narrow field of vision, then it is not happening. They disbelieve. They call “believing” scientific findings stupid. They call their disbelief high intelligence.

“A lot of people like myself, we have very high levels of intelligence, but we’re not necessarily such believers,” Trump said of climate change. “You look at our air and our water, and it’s right now at a record clean.”

In disbelieving the present observable realities, they certainly disbelieve future projections. If they disregard the fact that white-nationalist violence has worsened and U.S. law enforcement does not know how to stop it, will they believe that it will get even worse? If they ignore the enormous racial disparities in wealth, will they accept the projection of the Institute for Policy Studies that the median wealth of black households will redline at $0 by 2053 and that Latino wealth will redline two decades later? If they cannot see the changing climate today, will they buy the assessment of the Fourth National Climate Assessment that “with continued growth in emissions at historic rates, annual losses in some economic sectors are projected to reach hundreds of billions of dollars by the end of the century—more than the current gross domestic product (GDP) of many U.S. states”?

Instead of science, they hunt for signs.

“Brutal and Extended Cold Blast could shatter ALL RECORDS—Whatever happened to Global Warming?” Trump tweeted weeks ago.

“US dominates Olympics,” tweeted Bill O’Reilly after the 2016 Rio Olympics. “How can this be if we are a terrible country that persecutes minorities? Press is deceiving world about the US.”

“Who could not be moved at the sight of a major political party naming Barack Obama, an African American, as its presidential candidate?” Dinesh D’Souza asked weeks before Obama’s election. “To me, there could not be a better sign that America has left behind its racist past.”

Signs reign in the realm of belief. Belief reigns in the realm of what we cannot or do not know. Let me say it differently. I know because of science. When I do not know, I believe or disbelieve. As such, the end game of the transformation of science to belief is the execution of knowing. And the end of knowing is the end of human advancement.

Do not get me wrong. We should not follow all scientific pronouncements blindly. I am not saying every scientist and scientific consensus is indisputable. For decades before the publication of Charles Darwin’s On the Origin of Species in 1859, the scientific consensus of polygenesis found that the races were separate species with separate origins. At the turn of the 20th century, the scientific consensus of social Darwinism found the white race had been naturally selected for the highest evolution. After World War II, the scientific consensus of black cultural pathology urged African Americans to assimilate into white America.

But scientific anti-racists on the margins did not respond to mainstream scientific racists by saying they didn’t believe their findings, by spinning out easily disprovable alternative facts, by walking away.

It is one thing to disbelieve scientific findings. It is yet another thing to dispute scientific findings. We dispute on the basis of training and expertise; by conducting and finding and presenting evidence; and by challenging assumptions, flawed study designs, and analyses of findings. Unlike disbelieving, disputing produces an intellectual exchange among open-minded scientists. Only the disbelievers, some of whom pose as scientists, are closed-minded and unwilling to change their mind in response to new evidence.

In order to reinforce the scientific certainty that human action and inaction are disastrously warming the globe and racist action and inaction are disastrously causing racial inequities, environmentalists and anti-racists must separate belief from science. Instead of caring about belief, environmentalists and anti-racists should care about knowledge, especially our own. Instead of asking, “Are you a racist?” we should be asking, “What is a racist?” Instead of asking, “Do you believe in climate change?” we should be asking, “What does climate change look like?”

To disconnect science from belief, environmentalists and anti-racists must disconnect the disbelievers from the power to make racial and climate policy. When disbelievers take power, they will always believe in the business of reproducing disbelief. Environmentalists and anti-racists must be in the business of reproducing humanity.