The Langlands program is an invitation to explore the unknown territories of mathematics.

对粗鲁的陌生人回以极度礼貌，很刺激。

I'm mentioning all this -- I'm mentioning all this because I think this is not merely a personal problem; you may think I'm wrong in this, but I think we live in an age when our lives are regularly punctuated by career crises, by moments when what we thought we knew -- about our lives, about our careers -- comes into contact with a threatening sort of reality.