This is a story about someone who made me think better.

Professor Lily Geismer taught me American history and was my thesis advisor. The years have rushed by, but I still vividly remember spending long hours in her afternoon seminars furiously jotting down notes.

Yet the most important things I learned from her don’t fit in a notebook.

She taught me what a good teacher should be. She praised me when I’d earned it and criticized me when I deserved it. She showed me that teaching demands honesty, fairness, and kindness all at once, without ever letting one overrule the others.

When I walked into my own classroom for the first time, that was the kind of teacher I wanted to be. I hope I made it.

She taught me how a historian should see the world as it was and as it is. I learned to look for the ways that the threads of the past pull on the world I see around me today. Before I took her classes, I hadn’t given much thought to 1950s housing policy in Detroit or senators from Arizona with coke-bottle glasses. I do now.

She made me think harder and write better. She waged war on my digressions and rambling. Her crusade against the words “is” and ‘was” drove me crazy when I got back a marked-up essay. But I’m better writer for it today. “Every effect has a cause,” she’d tell me, “Who had the agency? Who made this event happen?”

I’ve written over a dozen books at this point in my career. I expect I’ll write more. Every time I’ve put pen to paper or cursor to screen, that reminder has swirled around in my head.

Thank you, Dr. Geismer. I owe you the world.