The irritable exchange with my 14-year-old granddaughter ran through the entire evening like pesky thread someone was pulling out of the fabric of our family.

The occasion was the graduation of her brother, Cole. We were part of a crowd flooding into Mariucci Area at the University of Minnesota, along with the parents and relatives of 450 other seniors graduating from one of the large local high schools. Our counterpoint began as Sofie, her mom and dad, and other family members entered the arena for the ceremonies. Several Somali women passed us as we made our way through the doors.

There are many Somali women in Minneapolis in recent years, most of whom arrived since Sofie was born. They wrap their hair with veils, they seem to be universally slender and, with a certain style I envy, wear long, narrow skirts. As they passed, I commented to Sofie on how attractive their dress was.

I added, without thinking: "I've been buying those skirts recently. Local stores stock them because of the new demand. I call them my immigrant skirts."

Sofie looked aghast. "I think that's a terrible statement." "Why?" I asked, no doubt blinking in surprise. "Because we have immigrants from a certain culture who wear skirts, skirts are now available to all of us."

"I can't believe you said that," she said. It is tiresome to be corrected by one's grandchildren but I am used to it. However, I still did not understand her point. What had I said that was disrespectful? I had simply stated a fact.

Twice later in the evening Sofie brought up the topic, and was combative with my dogged resistance to admit I should not have said what I did.

"What's wrong with what I said?"

"But they are immigrants," she said. At 14 she struggled to find the sophisticated language to expand her objection.

Finally I retorted (by this time we are in the car riding home, back once again to this interminable exchange): "My grandmother was an immigrant from Ireland. I'm proud of that fact."

"It's not the same thing," she said quickly. "Why not?" I was growing less patient.

"Because your grandmother was white," Sofie responded vigorously. Her tone made me pause. There was some thought, some emotion or image just beyond my psychic vision calling to me. But what was I missing? I must be, what the Irish would call, "dead slow." And then, in slo-mo, a light was dawning. But the full revelation did not emerge for several more hours.

You see, Sofie is my granddaughter, and I never think of her in any other way. But she is also Latina, full-blooded Colombian. We met when she was 3 months old and I went to Bogota to help my daughter-in-law with her new baby. I have known Sofie all her life. I never think of the fact that she sees me as white, and herself as something else. Or that she experiences the fact of race differently than I.

Or that I mostly don't experience race at all. And that's because my Irish grandmother was white.

The term "white privilege" has always annoyed me, because it reminds me of my Catholic formation in which I was taught we are born with "original sin." I don't believe in original sin. How can I help being born white? I didn't ask for it. The accusation "white privilege" shouldn't be hurled at me as an insult by the left. Trigger points and microaggression language, all the vogue in higher education, seem fatuous terms to me. They were no part of the education world when I was at university. We weren't coddled, but treated as adults, cast into the seas of learning history and literature and totally on our own to deal with it. No overarching protection for us undergrads from the end of a Virginia Woolf novel, even if the thought of suicide dismayed us. Even if it has been a part of one's own life. I know the difference between fiction and fact.

I'm equally impatient with what has come to be known as "political correctness," a term hurled as an insult by the right. It's a catchall phrase often hauled out to silence some reasonable argument for fairness and justice, to silence the opposition.

But when my granddaughter who is of color noted that my Irish grandmother had been white and that recent Somali immigrants were not at all the same as the Irish, she had a point. Maybe "white privilege" simply means not having to think about race at all in this society. Maybe I have the condition and don't know it; that blind spot is why I could not understand what my granddaughter found offensive about my casual reference to immigrants and my own clothing. I don't have to think about race: I'm white in a white society. Sofie is compelled to think about race always: She is not "white" in a historically white-dominant culture.

Later in the evening I texted her. I said I had thought over our conversation and I was beginning to see what she had found objectionable in my casual reference to an "immigrant skirt." I added that my generation saw things differently than hers, but that some of us were capable of being retrained. And I told her the most important thing: "I love you." Her return text said everything: "It's O.K. love you too." By persisting, by pulling on the thread of my own blindness, she had woven a new, brighter thread into my awareness of her world, and of my own.

Judith Koll Healey is a Minneapolis author of several novels set in medieval France, and a biography of a 19th-century entrepreneur, Frederick Weyerhaeuser.