Sustainability isn't an option - it's our responsibility to future generations.

A vida é o que fazemos dela. As viagens são os viajantes. O que vemos não é o que vemos, senão o que somos.

The use of a program to prove the 4-color theorem will not change mathematics - it merely demonstrates that the theorem, a challenge for a century, is probably not important to mathematics.

家庭是第一所学校，母亲是第一位老师。