Question for Mr. Chiang

Mr. Chiang,
Science Fiction is a subject that many people enjoy, yet it is one of the most stereotyped topics out there. I was curious how you became interested in Science Fiction and where you get your ideas for short stories? Many authors say that they use their own personal experiences for stories and add certain twists to them. I would say I am not a Science Fiction buff or fanatic, but "Understand" was by far my favorite story in the book, and I was also wondering where you came up with that idea? Thanks for your time,
Sara McRay