Read the following paragraphs and answer the question.

     I’ve always been curious about people, and I’ve tried to learn what I could from them. Many times during long rides, I’d developed a rapport with my passengers—and quite often I’d received very good advice from accountants, lawyers, and plumbers. Maybe it was that this fellow clearly loved his work; maybe it was just the pleasant mood of a spring morning. But I decided to ask for his help. “Could I ask a big favor of you?” He didn’t answer. “I have a son，15, a good kid. He’s doing well in school. He wants a job. But a 15-year-old can’t get hired unless his old man knows someone who owns a business，and I don’t.” I paused. “Is there any possibility that you might get him some kind of a summer job— even if he doesn’t get paid?” He still wasn’t talking，and I was starting to feel foolish. Finally, at the airport, he said, “Well, the medical students have a summer research project. Maybe he could fit in. Have him send me his school record.” He scribbled something and paid me. It was the last time I ever saw him. 

What was the narrator's impression of the doctor after some talking?（）