Assessing scientific claims is hard enough when you stick to empirical evidence. When personal factors intrude, which they invariably do, such assessments get even trickier.
Personal factors smacked me in the face at a “Conclave on Political Polarization” I attended last month in California. An eclectic bunch of social activists and scholars from the political left, right and center brainstormed on how to overcome the polarization entangling American politics–and science. We touched on lots of divisive issues—from fracking to gay marriage—but our primary focus was climate change and inequality.
The organizers asked me to kick off the climate-change discussion by stating which claims are settled and which are contested. It is a settled “fact,” I noted, that human fossil-fuel consumption has increased atmospheric carbon dioxide, which in turn is driving up temperatures and sea levels.
I tried to present this information in a non-polarizing manner. As a concession to climate-change doubters, I said it is a contested “opinion” that if humanity “does not take dramatic steps to curtail fossil-fuel consumption, civilization may collapse.”
I didn’t expect anyone to object to my basic facts, but the very next speaker did just that. Philosopher Michael Zimmerman expressed doubts about the scientific consensus on climate change. He handed out a “Background Paper” compiled in 2013 by anthropologist Benny Peiser, identified by Wikipedia as a “climate change skeptic.” The sheet asserted that “there has been no net increase in global temperatures for about 16 years.”
What made Zimmerman’s presentation doubly disturbing is that I’d already gotten to know him a little. He is smart, informed, funny. I liked him. He didn’t change my mind about global warming, but he reminded me that not all global-warming doubters are ideologues or idiots.
The same thing happened when the conclave turned to other divisive issues. Several participants criticized conventional liberal-left views—which I largely share–of inequality, labor unions and education. If Republican candidates for President voiced these criticisms, I’d swipe them aside. It wasn’t so easy to reject the arguments of my conservative conclave colleagues, because I’d gotten to know them a little, and I liked them.
Occasionally, personal factors nudge me into shifting my views. In 2010, after I ranted about the perils of nuclear power on an internet talk show, I heard from the nuclear-energy advocates Rod Adams and Gwyneth Cravens, who presented me with evidence of the benefits of nuclear energy in a respectful, friendly manner. Eventually I concluded that my fears of nuclear energy were excessive, and I became a “pro-nuke nut,” as I put it in one post.
Personal relationships obviously play a huge role in politics. That was a major theme of the conclave. The key to overcoming polarization, some speakers said, is getting people on opposite sides of an issue to meet, so they have a harder time demonizing each other.
Some activists recalled changing their minds after getting to know political opponents. Others recalled changing opponents’ minds. In other words, astute activists exploit personal factors to advance their goals—just as astute polemicists appeal to readers’ emotions as well as reason.
But what happens when personal relationships push you in opposite directions? Example: Zimmerman and others at the polarization conclave criticized some environmentalists for being “alarmists,” whose warnings about climate change are exaggerated and counterproductive.
One researcher often accused of alarmism is NASA atmospheric scientist James Hansen, who has been warning about global warming since the 1980s. “Our planet, with its remarkable array of life, is in imminent danger of crashing,” Hansen wrote in his scary 2009 book Storms of my Grandchildren.
I liked Hansen’s book, and I liked Hansen, too, and trusted him, when I brought him to Stevens to give a talk in 2010. As I said at the conclave, I am an optimist by nature, and hope, I believe, is a better motivator than fear. But I am haunted by the possibility that Hansen’s frightening prophecies might turn out to be right.
At this point, many readers are surely thinking: Only facts matter! Personal relationships should have no effect on your assessments! Indeed. If I were an emotionless machine, making up my mind based entirely on “facts,” I would be a much better journalist.
John Horgan directs the Center for Science Writings, which is part of the College of Arts & Letters. This column is adapted from one originally published on his ScientificAmerican.com blog, “Cross-check.”
