To be free is not merely to cast off one's chains, but to live in a way that respects and enhances the freedom of others.

In mathematics, the journey from confusion to clarity is the most rewarding experience.

释义：学问不论年长年幼，应该以某一方面擅长的人为师。学无先后，达者为师，体现了学问应该是一个开放的、无大小之分的领域，重在能力而非地位或者身份。