Friday was International Holocaust Remembrance Day, the day when, 78 years ago, Soviet troops liberated Auschwitz, the Nazis’ biggest concentration camp, during the final months of World War II. Established by the United Nations in 2005, the day commemorates the killing of 6 million Jews, two-thirds of Europe’s Jewish population, as well as millions of others by the Nazis and their collaborators. We were troubled to learn that a new survey found that only 26 percent of Americans could correctly answer four questions about the magnitude of the Holocaust and its origins. Blame it on social media and the Internet, where, unfortunately, Holocaust denial and distortion take root.

During Friday’s annual ceremony at the United Nations, Karen Frostig, a Professor of Art at Lesley University in Cambridge, Massachusetts, described her work to commemorate a concentration camp where thousands of Jews, including her grandparents, were murdered. Speaking to the assembled diplomats, invited guests, and Holocaust survivors, she said she was inspired in her work during her first visit to the place where the camp once stood, when it occurred to her that she had an obligation to protect them with her memory.

That idea of protecting our loved ones with our memory prompted further discussion, especially as the nation was coming to terms with another kind of genocide: thousands of fatal encounters between young Black men and police, exemplified most recently by the brutal beating and death of 29-year-old Tyre Nichols in Memphis. His courageous mother, RowVaughn Wells, with both grit and grace, demonstrated the very meaning of protecting her loved one with her memory, as she described her son and their love for one another. The night he was beaten, she said, she had planned to make his favorite meal: sesame chicken.

Their bond was such that at the very hour of his assault, she felt a visceral pain — one that seemed to portend the grim outcome that awaited her and her family.

As we talked about events from the distant and immediate past, we realized that we also have a solemn obligation to protect our loved ones with our memory. In some ways, this sense of obligation is what drives us to study our ancestry, to learn all we can about those whose lives have shaped our own — even though our own families are often disinterested in what we learn. Their indifference in no way relieves us of our solemn responsibility.