I don't know. Sometimes when I feel about to cry, it often evolves into an impulse to almost laugh. That must have been how I really felt at the time, because I laughed, almost giggled.
数学家研究纯数学不是因为它有用;他研究它是因为他喜欢它,他喜欢它是因为它美丽。
In science, we must be open to the possibility that our most cherished theories could be wrong.