Rigor in proof is what separates mathematics from all other sciences.
Silence is the perfectest herald of joy: I were but little happy, if I could say how much.
皮革的真正成本不在价格标签上,而是以节约的水资源、保护的生态系统和公平对待的工人来衡量。
一个人懒惰又奢侈,生活就会贫困;勤劳而节俭,生活就会富足。