Question for Mr. Chiang

In your short story, "Understand," the characters gained incredible powers that could be used for good or evil. You seem to explore one of the major reoccurring questions in science fiction: if given superhuman strengths, would we use them for good or evil? Was that the main topic you wanted to explore in that story? If so, do you think that humans would use powers like that more for good or evil? Also, do you think that good usually overcomes evil as it did in your story?