Last year I talked to a primatologist in his mid-80s, still sharp, still in his office most days, a pleasant spot in California, surrounded by his books and by younger colleagues who adored him. He wore khakis and a red plaid shirt and desert boots — I didn’t know you could even find desert boots anymore — and had marvelous recall and sense of humor. I was there to ask him mainly about the work of a long-ago colleague of his, someone whose work overlapped with his but not enough to make things too competitive. They both worked for a certain lab early in their careers, though at different times, and had followed each others careers, and he remembered all sorts of gems and insights and stories, always in language colorful and plain and free of jargon. A splendid interview that at two hours was too short.

When we’d covered my main line of questioning, I asked him if he could tell me about the work he was doing back then, 60 years before — work that stirred some fundamental changes in the field. He laughed and said, “Well sure. That’s an interesting story to me. I’ll have to restrain myself.” Then he told me about it, utterly riveting work. I didn’t want to take more of his time at this point, so I skimmed my notebook and memory for things I needed to ask him but had not. My interviews tend to wander a bit. By then he’d grokked to this flightiness of mind.

DD: Oh. Where did you say you grew up?

Subject: You didn’t ask me.

DD: Where did you grow up?

Subject: I was born in Mountain View.

Sometimes you can’t say thank you emphatically enough.