过去总是与我们同在，因为它滋养着现在。

If you don't take risks, you can't create a future.

So given a Time Turner, I would tell my 21-year-old self that personal happiness lies in knowing that life is not a check-list of acquisition or achievement. Your qualifications, your CV, are not your life, though you will meet many people of my age and older who confuse the two. Life is difficult, and complicated, and beyond anyone’s total control, and the humility to know that will enable you to survive its vicissitudes.

追求数学真理是一项崇高的努力。

Sometimes the only way to heal is to first forgive yourself.

要像上帝一样，并追随祂，是理性生物的事业和幸福。

Memory is the only paradise from which we cannot be driven.