The essential function of art is moral.

I'm not gonna sing about love if I don't feel it.

用秤称一称，才能知道轻重；用尺量一量，才能知道长短。

"The best writing is that which makes the familiar strange and the strange familiar."

Take away love and our earth is a tomb.

I don't have any particular recipe [for developing new proofs] ... It is the reason why doing research is challenging as well as attractive. It's like being lost in a jungle and trying to use all the knowledge that you can gather to come up with some new tricks, and with some luck you might find a way out.