To say my grandfather didn’t agree with my assessment of Lenin is an understatement. If you asked artificial intelligence to sketch you a white Anglo-Saxon Protestant American character, it’s possible my grandfather would emerge. He once told me if I didn’t like America, I could always move to Mexico. When I complained about how hard it was to vote, he told me that probably meant I didn’t deserve to vote. To be clear, I figured out how to register and vote as an 18-year-old living away from home because there was no way I was ceding to him that I didn’t deserve to vote.

Last week, as I remembered, I thought of him sitting at the head of the table, listening to his granddaughter say things he thought were absolutely ridiculous. I’m sure he wondered which college professor had taught me this heresy and thought I was completely off my rocker, but he never told me to stop talking. He never said anything about preventing that professor from teaching me the ideas I’d brought home.

When I went back to college, my grandfather went to the local bookstore and bought himself a biography of Lenin — and read it — so that when I came home for Christmas, he was ready to engage. I still thought Lenin was cool, and there’s some part of my soul that has always wanted to be a revolutionary, but my grandpa came back with facts and knowledge, and he won the argument. I have not been as big a fan of Lenin since that conversation over Christmas dinner.

This is the model of civil discourse with young people that I’ve tried to emulate throughout my career. One of my colleagues once sat in on my class and told me she was impressed that I engaged every student’s idea. My go-to line is “that’s fair” and then I bring facts and knowledge. I never tell students not to speak. And if they say something that I can’t engage with facts and knowledge, I tell them to give me until the next time we see each other, and I always loop back. Fortunately for me, I mostly don’t have to buy a book like my grandfather did; I can use the internet.

My grandfather sowed the seed of understanding that I didn’t reap until I was much older. Young people get hit with a firehose of new ideas (perhaps this is even truer in today’s social media market) and they always have to talk it through. What they need is adults willing to engage them with facts and knowledge, not adults who shut them down. I’m sure my grandfather didn’t want to spend money learning about Lenin, but he did it so he could have an informed conversation with me. He had enough confidence in his ability to meet any idea. As Thomas Jefferson taught, my grandpa understood that a free marketplace of ideas requires us to engage any truth, even those we consider anathema, because that’s how we reveal the good and the bad.

Last Thanksgiving, sitting at his table, I was grateful he was a part of my life. I missed him and our conversations. I would love to know if he’d still be a Republican today. But the legacy he gave me as a model of how informed citizens should behave in this republic I honor daily. We should be ready to engage ideas, never closing off any avenues of inquiry, especially with our young people.

Leah Murray is a Brady Presidential Distinguished Professor of Political Science and the academic director of the Olene S. Walker Institute of Politics & Public Service at Weber State University.