During my sophomore year at Bates College, 42 years ago, I took a sociology course. I had no idea that such a thing existed — that people studied the way societies worked. My English professor said, “It’s all garbage. Interesting garbage, but garbage.” To me, though, it was pretty exciting. One day, the sociology professor asked us to say what “class” in this country we came from. I did not know the answer. So I watched as he asked, “Lower class?” and saw no hands go up, and then he asked, “Middle class?” Enough hands went up that I raised my hand, and then he asked, “Upper class?” and a few remaining hands went up.

Author Elizabeth Strout (Leonardo Cendamo)

My father was a university science professor, and my mother taught English in high school. We would certainly have been considered middle class. So how did I not know this?

How the others recognized what class they came from, I can’t say. But I think now this was during a time in our history when the country thought of itself as classless. We were taught this, without even knowing it. And yet I knew, of course, about the boy in elementary school who was so poor that no one spoke to him, how in third grade the teacher said to him one day, “You have dirt behind your ears. No one is too poor to buy a bar of soap.” I remember the kid’s face turning bright red. So I knew, without knowing.

And I knew, too, when I worked in the country store during the summer in Maine, when kids my age came in — summer people, holding their tennis rackets — that no matter how much I hoped to be friends, I did not exist for them.

After college, I worked in the secretarial pool at Bates College. This was in a windowless basement with other women who had worked there for years, and I saw how the professors treated all of us, with a degree of our not really being people. They dropped on our desks what they wanted typed and walked out.

Later, I worked in the office room of a textile factory, I worked in a nursing home, I sold mattresses on the sixth floor of a department store. For a year, I worked in a pub in England, and I saw that people could tell someone’s class by their accent. I think people wondered about my class — with my American accent, who knew? Back in New England, I worked as a cocktail waitress. I was thrown up on one night, and the manager didn’t care. I played the piano in cocktail lounges. I saw things that perhaps at the time I didn’t even know I was seeing, but much has come back to me as I write my stories now.

When I was working on my first novel, “Amy and Isabelle,” I thought I was telling the story of Isabelle Goodrow, who works in the office room at a mill and thinks she is better than the women she works with. Isabelle had planned on being a teacher, but her early pregnancy with Amy changed this course. Her comeuppance arrives when she has a terrifying situation in her life and realizes the women she works with are there for her.

The book was nominated for a prize, and it was not until I heard a judge mention that the book had some “interesting issues about class” that I knew I had written a book about class.

When I wrote my second book, “Abide With Me,” I described a town with women who could afford to stay home. Their boredom erupts in a controversy about the minister’s housekeeper, who is a working-class woman. I was beginning to see these things in a conscious way.

In “Olive Kitteridge,” there are class issues and cultural issues, but it wasn’t until I wrote “The Burgess Boys” that I was fully aware of what I was doing with class. The novel follows three siblings who all end up in a different class, and there is the Somali population that has come to Maine as well.

(Random House)

With “My Name Is Lucy Barton,” I very consciously pushed this to the furthest point and made Lucy come from terrible poverty. I gave her sister the experience of that boy in my elementary school. (He has since died.) Lucy crosses class lines, becoming arguably an upper-middle-class woman. “Anything Is Possible” gives glimpses into the lives of people from her past; one man is her cousin with whom she used to find food in a dumpster.

But mainly and mostly I am writing about people. People are what interests me. Always, I have wondered: What does it feel like to be another person? This question is the furnace behind my work. But when you write about people, you are writing about class. Time and place in history determine a great deal, and if you consider place to be a place in society, then that shapes a life, as well.

Now class is being talked about — a little bit — in this country. Many people speak of the working class as being without education and having low incomes. But a friend of mine who spent his career teaching working-class studies suggested to me that it may be more helpful to think about class not in terms of education level or even income level, but in terms of the sense of power that people feel over their own lives. This helps us understand things differently.

And it makes me think of my own parents, who did not feel powerful, even though they were white and Protestant and perhaps should have felt a part of society. But, in truth, they shared with each other a fear of the world, a distrust of things they knew about only vaguely. And it may be this quality — which I absorbed — that allows me to write about people of different classes.

I think of my English professor’s response to my sociology course: He was right that it was interesting, but he was wrong that it was garbage. It is not garbage at all.

Elizabeth Strout is the author of six novels, including, most recently, “Anything Is Possible.” At the National Book Festival on Sept. 2, Strout will speak at the Fiction Stage from 10:20 to 11:05 a.m. and sign copies of her novels from 11:30 a.m. to 12:30 p.m.