United States politicians are no strangers to using unkind language against their opponents. It's a trend that dates back to at least 1800 when, during the presidential campaign, Thomas Jefferson hired James Callender to slime John Adams. But Alexander Theodoridis, who teaches political science at the University of Massachusetts Amherst, says that today's partisanship can lend itself to particularly dehumanizing language not only between political opponents, but also between regular Americans who belong to opposite political parties.

Theodoridis told NPR's Weekend Edition that "dehumanizing language," which includes people referring to others as animals, can lead to people believing that those who disagree with them don't deserve the same treatment or respect as those who agree with them.

"That is often where things lead," he said. "As either a justification post hoc for treating somebody differently or, in some cases, a precursor to treating a group differently."

One fear is that this kind of dehumanization leads to violence. Another is that it leads people to believe in conspiracy theories that further demonize the people they disagree with. Theodoridis says while both Democrats and Republicans use this kind of language, Republicans tend to believe conspiracy theories like QAnon more easily.

"I think part of that is just the composition of the parties," Theodoridis said. "One feature of the sorting that has happened in terms of who is a Democrat and who is a Republican, there is this sort of diploma divide, and I think that's a factor."

In an interview with NPR's Lulu Garcia-Navarro, Theodoridis reflects on the political polarization of this moment, the dehumanizing language that has risen up and where we go from here.

Interview Highlights

How do you capture how dehumanizing language has seeped down from politicians to the body politic in your studies?

One of the measures we use literally shows people a "ascent of man" picture, which is basically the image where you have where you go from sort of a stooped ape-like figure up to a standing human. And we ask them, how evolved do you think these groups are? And we ask them, Democrats and Republicans, how evolved?

And what we find is around 80% of people rate their own side higher than they rate the other side. And almost 70% of people rate their own side more than 10 points higher than the other side. And the average is in the 30s, like 35-point difference. So this is a pretty substantial gap.

And the fear is that our use of language, or how we talk, can lead to action, or in this case, violence.

I don't want to be alarmist. I don't think that we're very close to widespread political violence, largely because I think most people in this country are still fairly happy and are not concerned enough with politics on a day-to-day basis to take to the streets and do awful things.

But we asked people to give a [prison] sentence to somebody who had attacked a senator from one party or the other, randomizing the party of the senator and those who dehumanize more give a more lenient sentence. Right. So they view it as less of an offense when you attack the other side than when you attack their own side.

Other social scientists we have spoken to wonder if the genie can actually be put back in the bottle. I will say, as someone who has covered countries where there is deep polarization outside of the United States, it is hard to roll that back.

My thoughts on this are actually somewhat pessimistic. We long for a period in our history in the latter part of the last century where polarization along party lines, not necessarily along other lines, but along partisan lines, was not very pronounced. Your race, religion, education level, didn't necessarily predict your partisanship the way that it does today. And because all those identities are aligned, it becomes this sort of superordinate, super powerful identity.

So then where should we go from here? Because what I hear over and over again from voters is that they are tired of this partisanship and yet they are part of this partisanship.

That's right. So I really do think the focus should be, first of all, on just trying to lower the temperature and I think that falls largely on elites, on elected officials. I think we should hold them to a higher standard and the media should hold them to a higher standard in terms of not stoking these fires in ways that can be dangerous.

But beyond that, I think we should really look for ways to make it so that our government can work effectively under polarization, because I think this is a much more natural state of affairs than the kind of odd period historically that we have recently emerged from where the parties weren't really aligned with ideology and all sorts of characteristics.

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