And I hope you will come back here to Harvard 30 years from now and reflect on what you have done with your talent and your energy. I hope you will judge yourselves not on your professional accomplishments alone, but also on how well you have addressed the world's deepest inequities…on how well you treated people a world away who have nothing in common with you but their humanity.

A good mathematician is someone who can see analogies between theorems; a great mathematician is someone who can see analogies between analogies.

出自汉·桓宽《盐铁论·力耕》。非，不是。宝，这句话指好的办法。道，途径、方法。治家并不是只有一种有效的方法，治国并不是只有一条可行的途径。这句话言治家与治国一样，都有许多不同的方法，当事人应当努力寻求，不必因循守旧而无所作为。

The world is full of magical things patiently waiting for our wits to grow sharper.

"Escribo sobre lo que me asusta porque creo que es la mejor manera de exorcizar mis demonios."

You are not only responsible for what you say, but also for what you do not say.