The most important thing about an interview is knowing how you intend to start.

After that, an interview should take on a life of its own, just like any other conversation. But the first time I interviewed Elie Wiesel, in 1985, I evidently forgot that detail.

At that time, Wiesel was already a towering figure — the Auschwitz survivor whose memoir, “Night,” spoke the unspeakable, the prolific author, the indefatigable advocate for human rights around the world. He was already the recipient of countless awards; a year later, he would receive the Nobel Peace Prize.

Now I was supposed to go interview him? And ask him what, exactly?

Overwhelmed, I called Harry James Cargas, the late, brilliant Webster University professor who had been friends with Wiesel for years. “Relax,” the professor said. “He puts his pants on one leg at a time, just like everybody else.

“Of course, he’s also a living saint.”

Gee, Harry, thanks. You have certainly been a help. (I think, or hope, I put it better than that.)

But Elie Wiesel knew he could intimidate people, and he never wanted to have that effect. A slight man, dark and urbane, he spoke softly — as if to draw his listener closer. He had cultivated the ability to modulate the magnetism — the charisma that made him a powerful speaker — to an enveloping warmth, dialed down to the proportions of daily life.

We talked a little about his latest book, “The Fifth Son,” a novel about the American children of survivors, about the fact that the Hungarian town where he grew up, Sighet, wasn’t too far from the Rumanian town where my mother was born.

Then, in an instant, I knew what I needed to do. I reached into my purse and took out a photo of my 2-year-old daughter, Jordan. A “shayne, klayne, Yiddishe maydele,” we agreed. We looked at each other. We both understood.

A child that small . . .if she had been there, then . . . .not a chance. (Although he and two older sisters were reunited after the war, the six million include both of Wiesel’s parents and his little sister, Tzipora.)

We both started to cry.

After a while, he pulled himself together. “I love children,” he said quietly. “I cannot tell you how I love children.

“Maybe, one day, I will understand some things. But what has been done to our children (by the Nazis) arouses the eternal voices of anger and of protest.

“Even when the Messiah will come and all the questions will be removed, I will stick to this question, to this passion. I will never accept it at any level – not this human level nor the divine level.”

Wiesel and his wife, Marion, also had a child, their son Shlomo-Elisha. When he was about 6, the boy noticed the number that was tattooed on his father’s arm when he was 15, little more than a boy himself.

“All of a sudden, he said, ‘I am named after your father. Why isn’t your father here?’” Wiesel recalled. “I was so struck, I didn’t know what to say. I didn’t answer him.

“But I think it is not for him to give an answer, or even to receive one. It is for him to BE an answer. Jewish children are an answer.”

Through the years, we kept in touch. I don’t want to suggest that Elie Wiesel and I were close, but there were more interviews, “l’shanah tovah” cards, occasional phone calls. And he sent me his new books, always with an inscription.

So when I learned that he had died, at 87, I took out my copy of “The Fifth Son.” I wanted to read that first inscription again.

It says: “For Jordan’s mother.”`