this is an excerpt from House MD, a guy gets to ask Greg a question, which Greg proceeds to answer. the question was to the effect of:
why did you become a doctor? Clearly you don't like people, and if you like solving things you could have been a researcher.
When I was 14, my father was stationed in Japan. I went rock climbing with this kid from school. He fell and got injured, and I had to bring him to the hospital. We came in through the wrong entrance, and passed this guy in the hall. He was a janitor. My friend came down with an infection, and the doctors didn't know what to do. So they brought in the janitor. He was a doctor. And a Buraku - one of Japan's untouchables. His ancestors had been slaughterers, gravediggers. And this guy knew that he wasn't accepted by the staff, didn't even try. He didn't dress well. He didn't pretend to be one of them. People around that place didn't think he had anything they wanted, except when they needed him - because he was right, which meant that nothing else mattered. And they had to listen to him.
apparently, this is why House chose to be a doctor. It is intriguing - how people choose and / or not choose.